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Comparative organ imaging: the gastrointestinal tract
Abstract
Diagnostic radiology of the esophagus, stomach, small and large intestine, mesentery, and pancreas is reviewed. Survey and contrast radiography remain the principal imaging methods used to evaluate gastrointestinal diseases in animals. Of the other imaging techniques, scintigraphy has potential in assessment of esophageal and gastric motility disorders, and detection of intestinal hemorrhage. Ultrasonography is useful for imaging the pancreas and gastrointestinal mass lesions.
... Diagnosis of gastrointestinal obstruction with radiographs requires the observer's experience and parameters for the assessment of anatomical structures (Garrett et al., 2019;Graham et al., 1998;Kleine & Lamb, 2005;Lamb & Hansson, 1994). Radiographic evaluations in 11 dogs and 5 cats showed that gastric or small intestinal distension and reduced serosal details are common in small animals with gastrointestinal FBs (Tyrrell & Beck, 2006). ...
Background
In mynahs with foreign body ingestion, delayed diagnosis increases the risk of poor outcomes.
Objective
The aim of this study was to evaluate various radiologic features on plain and contrast radiographs in mynahs for assessing the presence of ingested foreign bodies.
Methods
In our cross‐sectional study, a total of 41 mynahs were included. The diagnosis was made by history, surgery, excision by forceps or excretion in the faeces. Overall, 21 mynahs were considered not to have a foreign body in their gastrointestinal tract. Plain and post‐contrast [oral administration of barium sulphate colloidal suspension of 25% weight/volume (20 mg/kg)] lateral and ventrodorsal radiographs from the cervical and coelomic cavity were taken. Different parameters including oesophageal, proventricular, and small intestinal diameters and opacities were assessed. Image evaluation was performed by two national board‐certified radiologists blinded to the final diagnoses.
Results
The inter‐ and intra‐observer reliabilities of the diagnostic features were significant (p < 0.001). The diagnosis of the foreign body was highly accurate [90.2% (95% CI: 76.9%, 92.3%)] with the sensitivity, specificity, and area under the representative characteristic curve of 90.0%, 90.5%, and 0.93%, respectively for plain radiographs. The size and opacity of the oesophagus, proventriculus, and intestinal loops as well as serosal details were significantly different between mynahs with and without foreign body intake (p < 0.05).
Conclusions
Lateral and ventrodorsal plain radiographs are highly reliable for diagnosing the presence of non‐opaque obstructing objects in the gastrointestinal tract of mynahs. Attention should be paid to the size and opacity of the oesophagus, extension, and opacity of the proventriculus, segmental opacity of intestinal loops, and decrease in serosal details.
... 2,14 Barium suspensions are safe and effective but are only useful in imaging the gastrointestinal tract since they cannot be absorbed into the body. 15,16 Iodinated CAs are thus the only option for angiography, lymphangiography, or myelography. No current agents are approved for bimodal imaging. ...
Here, we report the synthesis of robust hybrid iodinated silica-lipid nanoemulsions (HSLNEs) for use as a contrast agent for ultrasound and X-ray applications. We engineered iodinated silica nanoparticles (SNPs), lipid nanoemulsions, and a series of HSLNEs by a low-energy spontaneous nanoemulsification process. The formation of a silica shell requires sonication to hydrolyze and polymerize/condensate the iodomethyltrimethoxysilane at the oil/water interface of the nanoemulsion droplets. The resulting nanoemulsions (NEs) exhibited a homogeneous spherical morphology under transmission electron microscopy. The particles had diameters ranging from 20 to 120 nm with both negative and positive surface charges in the absence and presence of cetyltrimethylammonium bromide (CTAB), respectively. Unlike CTAB-coated nanoformulations, the CTAB-free NEs showed excellent biocompatibility in murine RAW macrophages and human U87-MG cell lines in vitro. The maximum tolerated dose assessment was evaluated to verify their safety profiles in vivo. In vitro X-ray and ultrasound imaging and in vivo computed tomography were used to monitor both iodinated SNPs and HSLNEs, validating their significant contrast-enhancing properties and suggesting their potential as dual-modality clinical agents in the future.
... The plain radiography is helpful in the detection of radio-opaque foreign bodies viz., granite stone, arachenut, cotton pad, plastic cover, fecoliths, sewing needle and mango kernels [10]. Advantage of radiographic investigation can be seen regurgitation and esophagitis due to such as hernias, tumors, foreign bodies ( Figure 2), megaesophagus, or vascular ring anomalies which often can be confused with the physiologic or chemical induced ones but for confirmation of the cause of the regurgitation or esophagitis, survey radiographs are needed [12]. phy should be explored [4]. ...
Gastric mucosal injury is very common in veterinary patients because of injudicious use of drugs which can hamper the normal mucosal defense mechanism, among such injuries gastritis is a common issue encountered in routine small animal practice. Over
centuries several approaches have been used to diagnose the gastric disorders and among those radiography imaging techniques are supporting diagnostic steps which are needed to determine diagnosis towards a case. So this paper gives a brief importance of those imaging techniques in various gastric problems especially gastritis and associated limitations.
... orientation, and margination such as stacking, plication, and bunching of intestinal segments; or abnormally shaped small intestinal luminal gas opacities. [1][2][3][4] Accuracy of subjective assessment of abdominal radiographs to diagnose gastrointestinal mechanical obstruction has been reported to vary between 61% and 80.7-89.1%. 5,6 This wide range has been attributed to variable radiographic changes associated with this disease process that can complicate the confidence of the diagnosis, such as lack of small intestinal dilation and poor abdominal serosal detail. ...
Abdominal radiographs are commonly used in dogs and cats that present with gastrointestinal signs. When initial abdominal radiographs are equivocal for the presence or absence of gastrointestinal mechanical obstruction, follow‐up abdominal radiographs may be recommended. Based on our review of the literature, no published study has been performed to evaluate the clinical utility of serial abdominal radiographs in such cases. The purpose of this study is to determine whether follow‐up abdominal radiographs increase diagnostic accuracy for mechanical obstruction. A prospective cohort study was performed on client‐owned dogs and cats with clinical concern for gastrointestinal mechanical obstruction and initial abdominal radiographs inconclusive for the presence of obstruction. Follow‐up abdominal radiographs were performed between 7 and 28 h of the initial radiographs; an abdominal ultrasound performed within 3 h of the follow‐up study served as the gold standard. A total of 57 patients (40 dogs and 17 cats) were recruited; 19 of 57 cases (11 dogs; 8 cats) were mechanically obstructed, all with nonradiopaque foreign bodies. Four blinded reviewers (2 radiologists, 1 radiology resident, 1 criticalist) separately assessed the initial and the combined initial/follow‐up radiographic studies for diagnosis of mechanical obstruction; for each observer, there was no significant change in accuracy (P = .058‐.87) for the diagnosis of mechanical obstruction. Given the lack of significant increase in diagnostic accuracy using follow‐up radiographs in cases of occult gastrointestinal mechanical obstruction, other diagnostic options (eg, abdominal ultrasonography) could be considered when survey abdominal radiographs are inconclusive for the diagnosis of mechanical obstruction in dogs and cats.
... Zur Diagnosestellung und Differenzierung zwischen gastrointestinalen und extragastrointestinalen Erkrankungen dienen häufig parasitologische und bakteriologische Kotuntersuchung, Blutbild und blutchemische Untersuchung sowie spezielle Blutparameter (z. B. spezifische PLI, TLI, Cobalamin, Folsäure) und Röntgen (3,11,12,30). Ergänzend kann eine sonographische Untersuchung nötig werden (3, 5, 9, 11, 14-16, 22, 24), ferner eine Endoskopie mit histopathologischer Untersuchung einer gewonnenen Gewebeprobe. ...
Gegenstand und Ziel: Zur Abklärung von Magen-Darm-Erkrankungen können unter anderem eine Sonographie und Endoskopie notwendig sein. Ziel der Studie war, mögliche Zusammenhänge zwischen Sonographiebefunden und folgenden Erkrankungen des Magen-Darm-Trakts aufzuzeigen: IBD (Inflammatory Bowel Disease), FRD (Food Responsive Diarrhoea), Ulzera und Infektion mit GHLO (Gastric Helicobacter-Like Organisms). Material und Methoden: Es erfolgte eine retrospektive Auswertung der Daten von 41 Hunden und 19 Katzen. Kriterien zur Aufnahme in die Studie waren akute oder chronische Magen-Darm-Symptome und der Ausschluss extragastrointestinaler Erkrankungen. Die weitere Abklärung bestand aus einer Sonographie und Endoskopie des Magen-Darm-Trakts sowie der histologischen Untersuchung von Gewebeproben. Ausgeschlossen blieben Tiere mit intestinalen Fremdkörpern, Neoplasien des Magen-Darm-Trakts und nicht klassifizierbaren Histologiebefunden. Ergebnisse: Bei 16 der 41 Hunde konnte eine IBD, bei 14 eine FRD, bei 5 Ulzera und bei 6 eine Infektion mit GHLO nachgewiesen werden. Bei 12 der 19 Katzen wurde eine IBD, bei 2 eine FRD, bei 2 Ulzera und bei 3 eine Infektion mit GHLO diagnostiziert. Im Fall von 26 Hunden und 4 Katzen ließen sich trotz klinischer Symptomatik und spezifischen Histopathologiebefunden keine sonographischen Veränderungen des Magen-Darm-Trakts feststellen. 14 Hunde und 4 Katzen zeigten teils multiple Befunde an extragastrointestinalen Organen. Bei den Katzen mit IBD waren oft Lymphadenopathien (4 Katzen) und eine verdickte Zona muscularis (6 Katzen) darstellbar. Weder bei der FRD noch einer Infektion mit GHLO ergaben sich spezifische Sonographiebefunde. Eine Infektion mit GHLO ließ sich bei nur 5 Hunden und 1 Katze, die nicht primär daran erkrankt waren, nachweisen. Ein Hinweis auf das Vorliegen eines Ulkus fand sich sonographisch in Form eines gasberandeten Areals mit Substanzverlust. Schlussfolgerung und klinische Relevanz: Sonographisch lassen sich bei einer IBD und einer Ulkuserkrankung Veränderungen finden. Ein unauffälliger Sonographiebefund schließt eine schwerwiegende Magen-Darm-Erkrankung nicht aus. Die histopathologische Untersuchung stellt weiterhin einen wichtige Baustein bei der Diagnosestellung der untersuchten Erkrankungen dar.
Summary
Objective: In addition to general and specific examinations, ultrasonographic and endoscopic examinations of the gastrointestinal tract may be necessary. This study aimed to determine possible relationships between the ultrasonographic and histopathological findings in the following diseases of the gastrointestinal tract: IBD (inflammatory bowel disease), FRD (food-responsive diarrhoea), ulcer and infection with GHLO (gastric Helicobacter-like organisms). Material and methods: The data of 41 dogs and 19 cats were analysed. The inclusion criterion was the presence of acute or chronic gastrointestinal symptoms in patients that had also undergone the standard diagnostic tests to rule out extragastrointestinal diseases. The patients underwent ultrasonographic and endoscopic examinations of the gastrointestinal tract, and a histopathological examination of the tissue samples from the endoscopy was performed. Patients with intestinal foreign bodies, neoplasms of the gastrointestinal tract or inconclusive histopathological results were excluded. Results: In a total of 41 dogs, 16 were diagnosed with IBD, 14 with FRD, 5 with ulceration and six with an infection with GHLO. Of the 19 cats, 12 had a diagnosis of IBD, 2 of FRD, 2 with ulceration and 3 with an infection with GHLO. In 26 dogs and 4 cats of the evaluated patients, the ultrasonographic examination did not show pathological changes, even though the patients had clinical symptoms and significant histopathological findings. However, in 14 dogs and 4 cats of the included patients, one or more pathological changes of the extragastrointestinal organs were found. In particular, cats with a diagnosis of IBD often presented lymphadenopathies (4 cats) or thickening of the zona muscularis (six cats). There were no specific ultrasonographic findings confirming an FRD or an infection with GHLO. Only 5 dogs and 1 cat without a primary diagnosis of infection with GHLO were positive for colonization with GHLO. The presence of ulcers was ultrasonographically indicated as areas showing a loss of wall layering with accumulation of gas. Conclusion and clinical relevance: Changes can be found during ultrasonographic examinations of patients with IBD and ulcer. However, the absence of findings in ultrasonographic examinations does not necessarily rule out serious gastrointestinal diseases. The histopathological examination still plays an important part in diagnosing the evaluated diseases.
... Because of the fluid content in the gastrointestinal tract, small quantity of blood or an active small hemorrhagia could easily be missed (Boysen et al., 2003). Despite that Computed Tomography examination is not available in every clinic, being also an expensive tool, compared with ultrasonography and radiography, it can offer additional information in case of abdominal trauma (Kleine and Lamb, 1989). ...
Accident could occur often and cats could be subjected to them. Examining a polytraumtized cat could present a challenge for the vet, being very easy to miss a small active bleeding, especially when that hemorrhage is located in the intestinal lumen. The aim of this case study was to highlight a possible hemorrhagia in the gastrointestinal tract, in the arterial time of contrast CT in a polytraumatized cat.
A 2 year, mixed breed cat was brought for radiography examination after it was hit by a car. Radiographic exposures were done for the spine and the abdomen and ultrasound examination was used to check for internal bleeding. Contrast agent Visipaque (iodixanol, 320 mgI/ml, producer Nycomed Amersham) was administered using automated injection after the patient was general anesthetized, the dose being adjusted by the device.
Clinical examination showed paleness of the mucosa and paralysis of the hind legs. Classic radiographic examination showed a luxation of the spine in the thoracic-lumbar area, and a normal aspect of the abdominal organs. The ultrasound do not reveal liquid in the abdominal cavity. Contrast CT revealed an accumulation of the contrast agent in the intestinal lumen in the arterial time of the procedure.
Contrast CT examination proved to be extremely useful and revealed an accumulation of the contrast agent in the intestinal lumen due to intestinal bleeding which explain the paleness of the mucosa in our patient. Radiography and ultrasonography have not proven reliable in this case for a diagnostic of internal bleeding.
... Ricordiamo che a volte il mezzo di contrasto ha completato il suo passaggio intestinale senza difficoltà anche in presenza di neoplasia; altre volte abbiamo rilevato alterazioni del tempo di transito [6], con aumento della peristalsi o permanenza del contrasto a distanza anche di 24 ore dalla somministrazione (foto 4). L'esame ecografico può fornire utili indicazioni circa la struttura della massa neoplastica [12,18,19]. L'esame deve essere effettuato previo adeguato trattamento antimeteorico e deve precedere l'esame contrastografico, a causa dell'impedimento esercitato dal solfato di bario nei confronti del passaggio del fascio ultrasonoro. ...
Mesenchymal or connective tissue tumours of the urinary system in dogs are rare. The first clinical case describes the development of a renal fibroma for which the general signs were lethargy and reduced exercise tolerance. It was diagnosed by ultrasonography of the abdomen. The second case recalls the steps to take for diagnosis of acute haematuria and a bladder mass. A partial cystectomy was performed. A leiomyosarcoma was found on histological examination of the ablated tissue. The prognosis for these two types of tumours is guarded, in particular for the leiomyosarcoma.
... Diente die abdominale Sonographie im Kleintierbereich zunächst hauptsächlich der klinischen Diagnostik bei Hund und Katze (11,23,76,85,94,125,123,170,171) (8,112,113) in den letzten Jahren, auch wenn diese Tiere selten wegen symmetrischer Alopezie oder palpierbarer Veränderungen im kaudodorsalen Bereich in der Tierarztpraxis vorgestellt wurden (112,113). Der Einsatz anderer gängiger Diagnostikinstrumente wie der Radiographie gestaltete sich für den Zystennachweis aufgrund der ähnlichen Darstellung von Ovarialzysten, Trichobenzoaren und abdominalen Tumoren (8) ...
... Ingestion of various foreign bodies like bones, choke belts, fruit pits, stones, plastics, toys, fish hooks, sewing needle and bottle caps were reported to cause gastrointestinal obstruction in dogs (Mahesh et al., 2008). Diagnostic radiography can be considered as the primary imaging technique for the evaluation of gastrointestinal affections (Kleine and Lamb, 1989). Also, radiography is a useful diagnostic tool that reveals intestinal ileus (Hedlund and Fossum, 2007) with the equipment easily available (Rose and Neiger, 2013). ...
Thirty dogs presented with a history of chronic vomiting which did not subside after symptomatic medical management were included in the study. In all the dogs, clinical examination showed varying degrees of gastrointestinal involvement. All the animals were subjected for radiography to diagnose the cause of vomiting. Survey radiography aided and enabled in the diagnosis in 27/30 dogs with gastrointestinal affections as megaoesophagus, gastrointestinal foreign bodies, gastric dilation and volvulus, intussusception and megacolon. Accurate diagnosis helped to adopt standard protocols for the management of the conditions. Radiography proved to be a good and primary diagnostic tool for the detection of most of the gastrointestinal affections and helped in the selection of appropriate treatment modality.
... Zur Diagnosestellung und Differenzierung zwischen gastrointestinalen und extragastrointestinalen Erkrankungen dienen häufig parasitologische und bakteriologische Kotuntersuchung, Blutbild und blutchemische Untersuchung sowie spezielle Blutparameter (z. B. spezifische PLI, TLI, Cobalamin, Folsäure) und Röntgen (3,11,12,30). Ergänzend kann eine sonographische Untersuchung nötig werden (3, 5, 9, 11, 14-16, 22, 24), ferner eine Endoskopie mit histopathologischer Untersuchung einer gewonnenen Gewebeprobe. ...
Objective:
In addition to general and specific examinations, ultrasonographic and endoscopic examinations of the gastrointestinal tract may be necessary. This study aimed to determine possible relationships between the ultrasonographic and histopathological findings in the following diseases of the gastrointestinal tract: IBD (inflammatory bowel disease), FRD (food-responsive diarrhoea), ulcer and infection with GHLO (gastric Helicobacter-like organisms).
Material and methods:
The data of 41 dogs and 19 cats were analysed. The inclusion criterion was the presence of acute or chronic gastrointestinal symptoms in patients that had also undergone the standard diagnostic tests to rule out extragastrointestinal diseases. The patients underwent ultrasonographic and endoscopic examinations of the gastrointestinal tract, and a histopathological examination of the tissue samples from the endoscopy was performed. Patients with intestinal foreign bodies, neoplasms of the gastrointestinal tract or inconclu- sive histopathological results were excluded.
Results:
In a total of 41 dogs, 16 were diagnosed with IBD, 14 with FRD, 5 with ulceration and six with an infection with GHLO. Of the 19 cats, 12 had a diagnosis of IBD, 2 of FRD, 2 with ulceration and 3 with an infection with GHLO. In 26 dogs and 4 cats of the evaluated patients, the ultrasonographic examination did not show pathological changes, even though the patients had clinical symptoms and significant histopathological findings. However, in 14 dogs and 4 cats of the included patients, one or more pathological changes of the extragastrointestinal organs were found. In particular, cats with a diagnosis of IBD often presented lymphadenopathies (4 cats) or thickening of the zona muscularis (six cats). There were no specific ultrasonographic findings confirming an FRD or an infection with GHLO. Only 5 dogs and 1 cat without a primary diagnosis of infection with GHLO were positive for colonization with GHLO. The presence of ulcers was ultrasonographically indicated as areas showing a loss of wall layering with accumulation of gas.
Conclusion and clinical relevance:
Changes can be found during ultrasonographic examinations of patients with IBD and ulcer. However, the absence of findings in ultrasonographic examinations does not necessarily rule out serious gastrointestinal diseases. The histopathological examination still plays an important part in diagnosing the evaluated diseases.
Radiographic exams still the main form to evaluate small bowel in all its extension, and when survey projections are not diagnostic, barium series are used although its sensibility can be imitated by filled overlapped loops, difficulting detailed mucosa visualization. The objective of this study was to adjust an exam technique with intestinal double-contrast, based on techniques used in the human medicine, which resulted satisfactorily in the demonstration of the mucosal surface in the 30 dogs submitted to the exam. The double-contrast in the lumen was achieved by a combination of a positive contrast medium, recovering the mucosal surface, and a negative filling the lumen. Ambient air and carboximethylcelullose were the negative contrast medium tested and both were radiographicaly similar.
Radiographic exams still the main form to evaluate small bowel in all its extension, and when survey projections are not diagnostic, barium series are used although its sensibility can be imitated by filled overlapped loops, difficulting detailed mucosa visualization. The objective of this study was to adjust an exam technique with intestinal double-contrast, based on techniques used in the human medicine, which resulted satisfactorily in the demonstration of the mucosal surface in the 30 dogs submitted to the exam. The double-contrast in the lumen was achieved by a combination of a positive contrast medium, recovering the mucosal surface, and a negative filling the lumen. Ambient air and carboximethylcelullose were the negative contrast medium tested and both were radiographicaly similar.
The purpose of this study is to evaluate the influence of kibble shape and fiber content of commercial dry foods on gastric emptying in healthy cats. Eight healthy cats were used to evaluate four different diets which varied in shape of kibble (round versus triangle) or fiber content (low versus high). Diets were labeled with 99mTc-mebrofenin and gastric emptying was evaluated with nuclear scintigraphy. There was a significant difference between the kibble shapes at both T50 and T20. The triangle shaped kibble required significantly longer time than the round kibble to reach T50 (P= 0.02) and T20 (P=0.001). Diet fiber content did not have a significant influence on T50, and T20- The influence of caloric and water intake was assessed with division of cats into high, medium, and low intake groups. The caloric intake had its main effect at T50 with the lowest quartile of caloric intake requiring significantly less time to reach T50 than the middle group and upper quartile (P= 0.05). Water intake did not have a significant effect on gastric emptying in this study. There was no relationship or correlation between the surface area of the food (cm2/kg) and T90, T50, and T20.
Iohexol was administered orally in five dogs. The dose, gastrointestinal (GI) transit time, appearance of mucosal patterns and side effects were studied. Three different doses (525, 700, 875 mgI/kg) were used in each dog at 1-week intervals. GI transit time was rapid. In each dose, gastric emptying commenced immediately after administration of the contrast medium, and was completed within 30–60 min with doses of 525–700 mgI/kg and 90–120 min with 875 mgI/kg. Large intestinal filling was observed within 60-90 min. In the majority of studies, the mucosal border appeared as a thin homogeneous halo of lucency surrounding the more opaque bowel lumen contents. The contrast intensity was not adequate with the lowest dose. The image quality did not deteriorate along the GI tract. No adverse reactions were found. Iohexol is an alternative GI contrast medium in the dog when contrast media are contraindicated.
This paper completes a two part review of abdominal ultrasonography in small animals. Indications, examination technique and interpretation of abnormal findings are described and illustrated using clinical cases.
The aim of this study is to provide a description of the ultrasonographic and angiographic anatomy of the hepatic and portal veins in normal dogs. Knowledge of this anatomy is essential for the proper diagnosis and correction of hepatic vessel anomalies like portal systemic shunts. Cranial mesenteric portography was done in 10 adult mongrel dogs to visualize the portal vein and its branches while the hepatic veins were visualized using the transvenous retrograde angiography method. Longitudinal and transverse ultrasound scans of the liver were done in the same dogs in left and right lateral positions in order to determine the best positions for imaging the different liver vessels. The distribution pattern of the hepatic and portal veins could be demonstrated by both ultrasonography and contrast angiography. Hepatic arteries are not usually visualized ultrasonographically. Ultrasound provided dynamic information that could not be obtained by contrast radiography. Super imposition of all vessels in the angiographic studies made the description of the branches of the liver vessels difficult. The results of the present study suggest that both methods may provide important complementary information in the diagnosis and planning of surgical procedures for the correction of vessel anomalies in the canine liver.
An ultrasound pattern of corrugated, and sometimes thickened, bowel wall has been associated with pancreatitis and small intestinal lymphangiectasia. In a retrospective study, records of dogs and cats with an ultrasound diagnosis of corrugated bowel were examined for age, breed, gender, presenting complaint, abdominal radiographic results, and final diagnosis. Eighteen dogs and six cats had an ultrasound diagnosis of corrugated bowel. The final diagnosis was pancreatitis (12 of 24), peritonitis (4 of 24), enteritis (2 of 24), pancreatic neoplasia (2 of 24), diffuse abdominal neoplasia (1 of 24), lymphocytic-plasmacytic enteritis (1 of 24), thrombosis/infarction (1 of 24), and protein-losing enteropathy and acute renal failure (1 of 24). The presence of bowel wall corrugation, although a nonspecific finding, should alert one-to the possibility of pancreatitis, enteritis, peritonitis, neoplasia, or bowel wall ischemia.
Two-dimensional ultrasonography was evaluated as an imaging modality in experimentally induced, acute pancreatitis in six dogs. Ultrasonic scans were performed once daily for one week following the induction of pancreatitis. Pancreatitis. Pancreatic inflammation, characterized by the development of nonhomogeneous masses and loss of echodensity in the pancreatic region, was consitently observed in all dogs. The results suggest that pancreatic ultrasonography may be a valuable technique for evaluating dogs with spontaneously occurring, acute pancreatitis.
Chronic ulcerative colitis is described in dogs. Most breeds are afflicted, and it occurs with equal frequency in both sexes. All ages of dogs can be afflicted, but dogs less than 2 yr of age comprise the largest group of affected animals. It occurs most frequently in boxer dogs, and in this breed, there are histopathologic changes that differ from the histopathologic changes in other breeds. Diagnostic procedures and therapy are discussed. The disease is compared and contrasted to ulcerative and granulomatous colitis in man.
Experimental colonic rupture in rabbits followed by an enema of barium sulfate or water-soluble radiographic contrast media was, without treatment, uniformly fatal. Surgical repair of the colonic rupture and peritoneal lavage resulted in only 10% survival in animals with peritonitis due to feces mixed with barium. Fifty percent of animals with peritonitis due to feces mixed with water-soluble media, and in which surgical repair was performed promptly, survived. These results suggest that water-soluble contrast materials be more strongly considered for employment when a contrast enema is considered indicated during acute-phase abdominal illness.
Aspiration of a water-soluble contrast medium (Hypaque) caused acute pulmonary edema in a patient with Boerhaave's syndrome who died shortly thereafter. The clinical course and serial chest radiographs and autopsy findings are presented. The high osmotic activity of Hypaque is considered to be the pathophysiological mechanism responsible for the pulmonary edema.
The recognition of gastrointestinal abnormalities by computed tomography depends on the systematic evaluation of (1) bowel position, (2) bowel wall thickness, (3) bowel contour and (4) the integrity ofperivisceral fat planes.
The administration of single and multiple bolus intravenous contrast followed by automatic mode scanning has increased the scope of diagnostic information attainable. The technique called Computerized Tomo-angiography (CTA) is applicable in the assessing of the location and extent of mediastinal mass lesions and in determining whether the lesions are isolated or multiple. It has also been found useful in determining lesion vascularity, in evaluating aneurysms and aortic dissection, in evaluating cardiac and pericardial disease and in assessing patients with superior vena cava syndrome. The text is divided into three main sections - technical considerations, normal anatomy, and abnormal anatomy. The normal anatomy section correlates enhanced CT images with cross-sectional anatomical sections and with illustrative diagrams and explanatory text. In each chapter, advantages and disadvantages as well as the limitations of the technique are described.
THE TWO major categories of contrast agents currently used to opacify the lumen of the gastrointestinal (GI) tract are barium sulfate suspensions and the iodinated water-soluble materials. Despite an extensive experience with these contrast media in the GI tract, confusion remains over their proper utilization. This article reviews the indications, uses, and risks of the commonly employed GI contrast agents.Barium Sulfate Suspensions
Barium sulfate is almost totally inert within the GI tract, having little physiological effect other than responses to volume and fluidity.1 Many commercial barium products are available for examining the GI tract; they vary widely in regard to density, viscosity, and ability to coat the mucosal surface. Many barium products have wide application throughout the GI tract, while others are specifically formulated for more limited use, such as double-contrast examination of the stomach or colon.
It was hypothesized that double contrast gastrography (DCG) in the dog and cat would be more sensitive and specific than single contrast gastrography (SCG). In 13 dogs and three cats single and double contrast studies were performed and final diagnoses confirmed. DCG was found to be more sensitive and specific than SCG in detection of gastric disease. The loss of specificity of DCG was due entirely to technical difficulties that when recognized, were avoidable. The increased sensitivity of DCG included the ability to characterize the appearance as well as the location of the lesion. A discussion of the DCG appearance of some gastric lesions is included.
Twelve dogs of various breeds, age and weight were injected with xylazine hydrochloride by intravenous and intramuscular routes at various doses. Radiographs of the abdomen were made prior to and at 30, 60 and 90 minutes after injection. The drug produced dilatation of the stomach and the intestines. Radiographic changes were consistent with gastric dilatation and paralytic ileus
Gastrografin (diatrizoate meglumine and diatrizoate sodium solution) was used to evaluate its performance as a gastrointestinal-tract contrast medium in ten cats. It was administered through an orogastric tube to ketamine hydrochloridesedated, nonatropinized, mature cats at a dose rate of 22 mg/kg. Gastric emptying and largeintestinal filling were observed within 30–60 minutes in seven cats and in 120 minutes in the remaining three cats. The mucosal detail of the small intestine was poor, being represented by a homogeneous “halo” of decreased radiodensity surrounding the more radiodense intestinal luminal contents. The contrast medium refluxed into the esophagus in six cats. Some contrast medium precipitated in the stomach and small intestines in all ten cats. Urinary-tract opacification occurred in all cats and was first seen 60 minutes after Gastrografin was administered. Gastrografin satisfactorily opacifies the lumen of the gastrointestinal tract of cats. It has physical and physiologic characteristics that preclude its use for routine gastrointestinal contrast studies. These characteristics are reviewed in this article.
Soft tissue calcification is known to occur in association with chronic renal failure. This soft tissue calcification is frequently recognized microscopically, but infrequently identified radiographically. This paper reviews the role of chronic renal failure in soft tissue calcification and presents three case histories of chronic renal failure in dogs in which soft tissue calcification of the stomach, kidneys, and footpads was detected radiographically. In all three dogs, gastric-wall mineralization was visible radiographically as thin, linear, mineralized densities. Renal mineralization was seen radiographically in two of the dogs. One of the dogs had nodular mineral deposits in the footpads of all feet. Although microscopy confirmed the soft tissue calcification of these and other structures, there was poor correlation between microscopic and radiographic degrees of visceral soft tissue calcification. There was also poor correlation between the degree of calcium and phosphate imbalance and the extent of radiographic evidence of soft tissue calcification.
Normal dog swallowing dynamics were analyzed and correlated with specific structures. There were oropharyngeal, esophageal, and gastroesophageal phases. The oropharyngeal phase was characterized by food prehension and bolus formation (oral stage), reflex pharyngeal peristalsis (pharyngeal stage), and reflex cricopharyngeal sphincter relaxation (cricopharyngeal stage). The esophageal phase was characterized by primary peristalsis initiated by the oropharyngeal phase and secondary peristalsis which occurred in response to mechanical stimuli from a bolus in the esophagus. There was a post-peristalsis refractory period during which new peristalsis would not occur. Repeated rapid swallowing would, therefore, result in accumulation of ingesta in the esophagus. The gastroesophageal phase occurred when a bolus passed through the gastroesophageal junction, an area which serves as a lower esophageal sphincter. Gastroesophageal reflux was observed as a normal, infrequent event followed by rapid esophageal clearance. Low doses of tranquilizers had no significant influence on swallowing function. The differences observed between sternal and lateral recumbent postures related only to the rate of food consumption which, in turn, influenced esophageal motor response and inhibited gastroesophageal closure. These differences did not adversely affect the autonomous phases of swallowing.
During a 10 year period. 20 dogs with primary localized neoplasia of the small intestine were presented at the University of Bristol Veterinary School. Half the tumours were carcinomas, the remainder being lymphosarcomas (5 cases), leiomyosarcomas (3 cases) and leiomyomas (2 cases) Lesions occurred at a variety of locations along the tract, but descending duodenum (6 cases) and terminal ileum (4 cases) were the commonest sites. Clinical findings varied. All dogs except three presented with chronic illnesses, but only seven showed signs immediately referable to alimentary tract disease. Abnormalities were found at radiographic examination in all cases except one and provided or confirmed the indication for laparotomy. Ten animals were destroyed at the time of surgery, two died during the immediate post-operative period and three were later destroyed because of suspected recurrence. Four dogs are reported well at intervals of between nine months and two years following surgery.
In two dogs spontaneous pneumoperitoneum developed following gastric volvulus. The pneumoperitoneum resulted from splenic necrosis and Klebsiella pneumoniae peritonitis in one and from a gastric perforation near the gastroesophageal junction in the other. The first dog was successfully treated by splenectomy, abdominal lavage, and systemic antibiotic therapy; the other was treated by closure of the perforation, tube gastrostomy, abdominal lavage, and systemic antibiotic therapy. One dog was euthanized four weeks after surgery because of metastatic cancer, and the other was euthanized six weeks after surgery due to recurrence of abdominal distention and peritonitis.
Radiographic diagnosis of gastric mucosal disease has not been reported in the cat. This may be due to the difficulty in making these diagnoses with survey or single contrast radiography. Double contrast gastrography (DCG) allows direct visualization of gastric mucosal surfaces. The DCG technique in the cat is described, and the normal radiographic appearance is illustrated.
Contrast radiography of the alimentary canal was conducted in six adult sheep with barium sulfate (70% W/V, 25–30 ml/kg). A period of 12 hours was adequate for opacification of most parts of the gastrointestinal tract. The presence of contrast medium in different parts of the alimentary canal was noted for as long as 60 hours. The right lateral view was adequate for visualization of most structures, but the typical laminar mucosal pattern of the omasum and the spiral mucosal folds of the abomasum were demonstrated better on the ventrodorsal view.
Abdominal discomfort in the foal presents a diagnostic challenge, because the small size of the foal precludes rectal palpation. Standing lateral horizontal beam abdominal radiographs using conventional techniques were evaluated as a diagnostic aid to identify the presence and location of gastrointestinal disorders in foals presented with colic. Forty foals were radiographed prior to surgery (20 foals), necropsy (7 foals), or clinical diagnosis (13 foals). Clinical, surgical, or necropsy findings were then correlated to radiographic findings. Gastrointestinal disease was accurately identified on radiographs as the source of colic in 25 of 26 foals that had surgical or postmortem confirmation. The site of disease, whether gastric, small intestinal, large intestinal, or a combination, was accurately determined from radiographs. Standing lateral abdominal radiographs were determined to be a valuable diagnostic aid in the foal presented with colic.
A total of 22 radiographic studies was made to determine comparative gastric emptying times of two different solid test meals (intact kibble food and ground kibble food mixed with barium sulfate suspension) in four mature (15-26 months) normal Beagle dogs under controlled conditions. Complete gastric emptying times of the intact kibble and ground kibble meals of a given dose (8 g/kg of dog food plus 5-7 ml/kg of the contrast agent) ranged from five to ten hours (7.6 ± 1.98 hours with intact kibble meal and 7.0 ± 1.86 hours with ground kibble meal). Feeding a halfdose of ground kibble meal (4 g/kg of dog food plus 3.5 ml/kg of the contrast agent) resulted in complete gastric emptying times of four to six hours (4.7 ± 0.67 hours). Individual dogs had repeatable gastric emptying times although the times varied among different dogs.
Double contrast gastrography affords more accurate detection of gastric lesions because it allows direct evaluation of mucosal pattern contours. The technic involves the induction of gastric hypomotility with intravenous glucagon, gastric intubation for the introduction of air and high-density barium directly into the stomach, and positional manipulation for maximal air-barium interface demonstration. Some dogs require sedation. Although fluoroscopic observation is an asset in isolating gastric anatomic abnormalities, this study may be performed using conventional radiographic equipment without fluoroscopic guidance. Double contrast gastrography is used to demonstrate the stomach mucosal surface by coating it with high-density barium and having the mucosa contrast with the air-filled gastric lumen. There are three elements to each double contrast image: the dependent surface, the nondependent surface, and the barium pool. The barium pool is manipulated to coat the mucosal surface and fill depressions of the dependent surface. Protrusions of the dependent surface appear as radiolucencies in the barium pool. Depressions and protrusions of the nondependent surface are outlined by barium. Double contrast gastrography is indicated in dogs where clinical signs suggest anatomic changes in the gastric mucosal surface, e.g., neoplasms, ulcers, or polyps. Concurrent gastrointestinal motility evaluation is precluded by sedation and the glucagon-induced gastric hypomotility.
The sonographic appearance of intraabdominal abscess, excluding prostatic abscess, is presented. The most common sonographic pattern identified for intraabdominal abscess is an irregularly defined, hypoechoic mass with minimal to no through transmission. Definitive diagnosis of intraabdominal abscess using only sonography is not possible, as variations of this common sonographic pattern are imaged. Sonography is best utilized to scan an animal when there is a high suspicion of intraabdominal abscess with no overt physical or radiographic evidence, and to better characterize intraabdominal masses. Sonography can be used to assist in percutaneous aspiration, catheterization, and intraoperative localization of abscessation.
Acute, necrotizing pancreatitis was experimentally produced in three dogs by injection of oleic acid into the accessory pancreatic duct. The ultrasonic features of acute pancreatitis were compared with the radiographic and gross pathologic findings. It was concluded that ultrasonography was very useful for the detection and characterization of experimental pancreatitis. The results must be carefully compared with the ultrasonic abnormalities found in naturally occurring, acute canine pancreatitis before the usefulness of pancreatic sonography can be determined for this disease in the dog
Nuclear medicine has achieved an important role in the diagnosis of gastrointestinal (GI) disease in humans. Esophageal and gastric motility problems, gastroesophageal reflux, abnormal gastric secretory function, GI bleeding, and inflammatory diseases of the GI tract can all be evaluated using nuclear scintigraphy. The use of these techniques in human medicine, their advantages and disadvantages relative to other available diagnostic tests, and their potential application to veterinary medicine are discussed. Examples of esophageal and gastric motility studies performed on normal and abnormal dogs are included.
Cinefluorography and videoflurography were used to record and analyze the functional swallowing deficits of nine dogs with spontaneous oropharyngeal swallowing problems. Based on the clinical and radiographic signs observed in one dog with experimentally induced bilateral hypoglossal palsy and comparison with cinefluorograms of normal dogs, the nine spontaneous dysphagias were divided into five oral dysphagias and four pharyngeal dysphagias. Dogs with oral dysphagias had problems with tongue control and in prehending and transporting food and fluid to the oropharynx. On cinefluorograms, a poor closure of the oral egress led to the loss of contrast medium from the mouth, and a weak tongue-thrust action caused retention of contrast medium in the oropharynx. The clinical and radiographic signs could be duplicated by hypoglossal neurectomy. In contrast to the pharyngeal dysphagias, aspiration pneumonia was noticeably absent in oral dysphagias. The dogs with pharyngeal dysphagia had severe difficulties in transporting the food from the oropharynx to the laryngopharynx owing to a poor contractility of the pharyngeal muscles. The latter resulted in contrast medium retention in the pharynx and laryngotracheal aspiration. The need was stressed for a careful differentiation between oral and pharyngeal dysphagias on one hand, and cricopharyngeal dysphagias on the other hand. In oral dysphagias, cricopharyngeal myotomy appeared of no use. In pharyngeal dysphagias, cricopharyngeal myotomy severely aggravated the clinical signs by causing a cricopharyngeal chalasia.
A Y-U pyloroplasty was performed on five healthy adult dogs. Gastric emptying half times (t 1/2 GE) of a canned food meal were measured by scintigraphy three times before surgery and three times from 6 to 8 weeks after surgery. Fluoroscopic studies of gastric and duodenal motility were made before surgery and 3, 7, and 35 days after surgery. Clinical observations were made daily throughout the study. Gross and histologic evaluations of the gastroesophageal and pyloric regions were performed at the termination of the study. The t 1/2 GE was significantly decreased after surgery. By positive contrast fluoroscopy, the vigor of antral contractions was seen to be decreased in three of the five dogs. On days 7 and 35, fluoroscopic findings were comparable to preoperative studies. Duodenogastric reflux was recognized fluoroscopically in three dogs on four different occasions. This may reflect normal reflux patterns in the dog. No gastrointestinal problems were evident after surgery in four dogs. Reflux esophagitis developed in one dog after surgery, which resolved with therapy. Studies of the Y-U pyloroplasty after 2 months indicated that it decreased gastric emptying time of solid food. Results of postmortem examination showed no abnormal gross or histopathologic changes of esophageal, gastric, or proximal duodenal tissues.
The purposes of this study were to evaluate a technique for contrast gastrointestinal (GI) radiography and to define the normal radiographic anatomy of the foal GI tract as demonstrated by survey and contrast radiography. GI studies were performed in five normal foals. Right lateral standing, right and left lateral recumbent, and ventrodorsal (dorsal recumbent) radiographs were evaluated. The recumbent lateral and ventrodorsal positions were preferred, although the right lateral standing position demonstrated most structures. Radiographic positions that clearly identified a specific GI region were determined. The dosage of contrast medium used (5 ml/kg of a 30% wt/vol barium suspension) was adequate to outline the GI tract. Transit times allowed evaluation of the large colon within eight hours.
To obtain radiographic information concerning the equine stomach, a gastrographic contrast examination is required. This study describes this procedure in detail. A powerful radiographic unit, the tubehead linked to an image intensifier and suspended by an electromechanical overhead gantry system, is required. To obtain accurately positioned radiographs during the fluoroscopic examination, a cassette holder with a stationary grid is mounted at the entrance window of the image intensifier. The examination is performed in the unsedated standing horse after 24 hours of starvation, using a combination of survey radiography and fluoroscopic viewing after the inflation of air, followed by the administration of barium sulphate suspension by stomach tube. The gastrographic contrast examination is performed in three experimental animals and 23 abnormal horses. Pneumogastrophy appeared to be valuable to diagnose gastric tumors, to differentiate between gastric tumors and other masses in the cranial abdomen, and to visualize gastric parasites, even in large horses. The use of barium sulphate suspension does not result in an adequate double contrast of the stomach, but it may aid to diagnose esophagogastric or pyloric stenosis and gastric or duodenal ulcers.
The effect of commonly used sedatives on gastrointestinal motility and transit time in cats was evaluated using barium sulfate in gastrointestinal contrast studies. Control studies were performed in nonsedated animals, and the results were compared with those obtained from each of five sedation studies (ANOVA; p < 0.05). The ketamine/acepromazine transit time (18 minutes) was shortened significantly compared with the control group (42 minutes), and both ketamine/acepromazine and ketamine alone resulted in significant increase in the number of gastric contractions. The level of sedation was evaluated subjectively and compared with the transit times to determine a chemical restraint method for potential clinical use that would have the least effect on transit time and motility yet provide adequate sedation. When sedation is necessary and motility is not a primary concern, the ketamine/acepromazine combination if recommended. If a gastrointestinal motility problem is suspected, the ketamine/valium combination should be used.
This paper is a retrospective analysis of the radiographic appearance of one benign and four malignant gastric ulcers in dogs. The benign gastric was diagnosed radiographically following gastric surgery and was healed at necropsy 28 months after diagnosis. Malignant gastric ulcers were confirmed at surgery and/or necropsy. None of the five ulcers penetrated the normally expected gastric contour. Mucosal fold pattern was either partially or completely effaced with all five ulcers. Undermining appeared to be present asymmetrically in the benign and one malignant ulcer, and symmetrically in one malignant ulcer. Tissue surrounding the ulcers joined the normal gastric wall very abruptly in three malignant ulcers. This transition was more gradual in the benign ulcer and was not identified in one malignant ulcer. None of these ulcers completely fit the criteria used in people to diagnose benign gastric ulcer. Prospective evaluation of more cases with a more thorough radiographic technique is needed
The normal radiographic appearance of the feline upper gastrointestinal (UGI) examination following oral administration of barium sulfate suspensions was described. Important findings included the minimal gastric air and small bowel gas present on survey abdominal radiographs. Gastric appearance was nearly constant. A normal duodenal pattern, referred to as a “string of pearls”, was described. Small bowel lumen size was consistently less than 12 mm. Small bowel mucosal patterns varied widely. The most commonly identified normal radiographic UGI patterns in this study were found consistently in a group of 26 cats thought to be without gastrointestinal disease. Because of the consistency of observation of many radiographic patterns, rapid gastric emptying, and a short small bowel transit time, normal UGI examinations in the cat present a more constant appearance than in the dog, thus making them more valuable as well as easier to conduct.
The diagnostic sensitivities of arteriography, intravenous (IV) Tc-99m sulfur colloid scintigraphy, and intra-arterial (IA) Tc-99m sulfur colloid scintigraphy were evaluated in a canine model of gastrointestinal bleeding. Fifteen dogs were studied at bleeding rates ranging from .4 to 1.0 ml/minute. All three studies were obtained in six of the 15 dogs. Intravenous scintigraphy was superior to angiography in two cases, inferior in three, and equal in one. No significant difference could be shown between these two tests at these bleeding rates. Intra-arterial scintigraphy was superior to angiography in four cases and equal in two (P = .06). It was superior to IV scintigraphy in five cases and inferior in one (P = .10). In this small preliminary study, IA scintigraphy appears to be superior to the other two modalities and may prove useful in the detection of acute bleeding at the time of negative arteriography, and in serial studies in patients receiving Pitressin.
Leukocytes have been labeled with indium-111-8-hydroxyquinoline complex. Seventy-five to 85 per cent of the initial activity has been obtained in the complex form of which 75 to 95 per cent is incorportaed with leukocytes. The polymophonuclear leukocytes are predominantly labeled, and the label has been found stable for at least 27 hours after invivo administration. The radioactivity clears from the circulating blood with a half time of 8 to 9-hours and accumulates in normal liver and spleen and in experimentally induced abscesses. The cells which have been labeled and damaged by heat concentrate mainly in the lungs. The in vivo distribution of the indium-111 labeled cells has been compared with the gallium-67 administered as citrate. The abscess to blood ratios of the indium-111 activity varied between 35 to 117, compared to 1.2 to 8 of the gallium-67. The abscess to liver, spleen, and kidney ratios are several fold higher with indium-111 leukocytes than with gallium=67 citrate. These results plus the suitable physical characteristics of indium-111 make the labeled leukocytes a better agent for the localization of abscesses.
If attempted nonsurgical evacuation of a twisted stomach is unsuccessful, as indicated (on radiographs) by a distinct gas bag ventrally and to the right in the abdomen, there is always a displacement of the dilated and gas‐filled fundus into the omental bursa. The fundus is trapped in that position by a ‘ring’ consisting of the splenic artery, the short gastric arteries, the left crus of the diaphragm and a part of the corpus of the stomach. The ‘ring’ strangulates the transition zone between the fundus and the corpus of the stomach. The displaced fundus thus forms the contents of an ‘inner hernia’ with the structures mentioned above functioning as the ‘hernial ring’.
The radiographic course of events after a successful evacuation of a stomach in torsion shows great variations from case to case. Sometimes the stomach returns to a normal position immediately, or within hours, after evacuation. In other cases it may remain ‘upside down’ for days or weeks without causing a functional disturbance. The variations of the radiological course as related to patho‐anatomical and clinical observations are discussed.
Esophageal neoplasms were diagnosed in 8 of 49,229 dogs seen over the last 11 years at the Veterinary Medical Teaching Hospital of the University of California at Davis. The neoplasms were primary in 2 dogs and metastatic to the esophagus in 6 dogs, with thyroid carcinoma being the most common site of the primary tumor. The most common clinical signs were regurgitation, dysphagia, weight loss, development of neck masses, and respiratory difficulties. It was concluded that the clinical signs often can be misleading. The interpretation of survey radiographs, barium contrast studies, or fluoroscopic studies often provide the initial data base. The final diagnosis requires histologic examination. Retention of air in the esophagus (with or without esophageal displacement) and motor dysfunction (with or without gross morphologic changes) are the most important criteria for radiographic diagnosis.
None of the tests employed currently to investigate esophageal transit is quantitative. The purpose of this study was to evaluate normal subjects and patients with a variety of esophageal disorders using a scintigraphic technique to quantitate esophageal transit. After oral administration of a bolus of water labeled with 99mTc-sulfur colloid, isotopic count rates were measured over the esophagus employing a gamma-camera on line to a digital computer. Esophageal transit was expressed as the percent emptying for each of the first 15-sec after the initial swallow and for 15-sec intervals after serial swallows. Sixty-two subjects were studied, including: normal volunteers; patients with motor disorders of the esophagus such as achalasia, diffuse esophageal spasm, and scleroderma; and patients with symptomatic gastroesophageal reflux both with and without esophageal motor dysfunction on manometic testing. Esophageal transit was decreased significantly after single and multiple swallows in patients with motor disorders of the esophagus. In addition, esophageal transit was abnormal in patients with reflux disease accompanied by abnormal motor function. In contrast, esophageal transit was normal after a single swallow, but incomplete after serial swallows in patients with reflux associated with normal esophageal motor function on manometry. We conclude that esophageal scintigraphy may be used to evaluate esophageal transit.
Radiographic anatomy of the gastrointestinal tract of the goat (Capra hircus) was studied. Intraluminal contrast medium was used to evaluate the mucosal surfaces of stomach and intestines, and extraluminal contrast medium was used to evaluate the serosal surfaces of organs in the peritoneal cavity.
The apparently random variability of the margination of the small bowel observed during contrast radiography prompted an investigation to determine the significance and aetiology of such a finding. Upper gastrointestinal tract contrast radiography of twenty-five dogs revealed a marked variation in the smoothness of mucosal margination. Gross and histological examination of the small bowel of these dogs revealed no lesions which could account for the variation in mucosal margination. It was noted that the spatial arrangement of the villi varied in such a way that the degree of irregularity of the mucosa observed radiographically could depend on the ability of the contrast medium to dissect around upright villi.
1.A review of improved standard techniques as well as newer radiological methods for the evaluation of gastrointestinal cancer is presented.
2.Double contrast barium examinations of the oesophagus, stomach, duodenum, and colon increase the capability for diagnosing and characterising small gastrointestinal mass lesions. Commercial products are available so that excellent double contrast examinations may be performed in any institution.
3.Diagnostic applications of angiography to the liver, pancreas, and alimentary canal are presented. The importance of assessing extent of disease by angiographic means is stressed. Therapeutic angiography, particularly in the control of gastrointestinal haemorrhage, is considered.
4.A number of newer interventional techniques including ‘skinny needle' percutaneous transhepatic cholangiography, transjugular liver biopsy, and percutaneous aspiration pancreatic biopsy are discussed.
5.In the evaluation of patients with gastrointestinal cancer, present radiological techniques allow for more accurate diagnosis, staging of disease, and even therapeutic assistance.