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ABSTRACT: Radiosynoviorthesis (RSO) has been established as a treatment modality for rheumatoid arthritis. Other forms of joint diseases like recurrent joint effusions after knee arthroplasties are under investigation. The aim of this study was to examine whether RSO therapy is effective in the application of an endoprosthesis and whether there are common causes of failure.
Between 1998 and 2005, 55 patients received RSO treatment (90Y colloid) for recurrent joint effusions after endoprosthetic knee replacement. A total of 46 patients were followed up and questioned anonymously according to a modified Knee Society Knee Scoring System (KSS) and Hospital for Special Surgery score. On the basis of patient records, a subgroup analysis of patients with revision surgery after RSO (subgroup A) and without further operative interventions (subgroup B) was performed.
Subgroup A comprised 46% (21/46) and subgroup B comprised 54% (25/46) of all patients. Most patients from subgroup A did not benefit from RSO. Of these 21 patients, 7 presented with low-grade infection, 7 presented with signs of endoprosthetic loosening, 2 presented with metal allergy, and 2 had undergone revision because of trauma.Patients in subgroup B experienced a significant improvement in pain (KSS score, from 22.5 to 34 points) and function (KSS score, from 62.9 to 77.3 points; Hospital for Special Surgery score, from 30.2 to 38.7) after RSO.
Radiosynoviorthesis resulted in an improvement in pain and function in ∼50% of patients with knee endoprostheses. In 85% of all patients, in whom RSO treatment failed, endoprosthetic complications like infection, loosening, allergy, and trauma were detected. In conclusion, RSO is a valid therapeutic option for joint effusions after knee arthroplasties. However, if RSO fails, a thorough exclusion of endoprosthetic complications should be performed.
Clinical nuclear medicine 08/2012; 37(8):727-31. · 3.92 Impact Factor
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ABSTRACT: Comparison of the diagnostic validity of positron emission tomography (PET) alone with integrated PET and CT (PET/CT) in the search for occult primary tumors in patients with cancer of unknown primary (CUP) site in the head and neck.
Thirty-nine consecutive patients with clinical CUP were investigated with PET and 38 patients with PET/CT. After initial diagnostic panendoscopy and histological confirmation of the cervical lymph node metastasis, either PET or PET/CT scanning was performed.
Integrated PET/CT had a significantly higher overall detection rate than dedicated PET alone (55.2% vs 30.8%; p = .039) and positive prediction rate (93.3% vs 46.1%; p = .01).
Integrated PET/CT showed to be superior to PET in the detection of the primary site of clinically occult tumors in CUP syndrome. However, a negative result should still be investigated further by means of panendoscopy with tonsillectomy and blind biopsies.
Head & Neck 11/2011; 33(11):1569-75. · 2.40 Impact Factor
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ABSTRACT: Concurrent chemoradiotherapy (CRT) is standard treatment for advanced head and neck cancer. Whether short induction chemotherapy (ICT) provides additional benefit or, in particular, predictive benefit for the response to chemoradiotherapy is an open question. The present study aimed to assess the feasibility, toxicity, and efficacy of induction with docetaxel and platinum salt (TP) and subsequent CRT.
A total of 25 patients with functionally inoperable cancer of the base of the tongue, hypopharynx, or larynx received 1 cycle of docetaxel (75 mg/m², day 1) combined with either cisplatin (30 mg/m², days 1-3; n = 23) or carboplatin (AUC 1.5 days 1-3; n = 2). Responders (n = 22, >30% tumor reduction, graded by endoscopy) and 1 non-responder received CRT (target dose: 69-72 Gy) with cisplatin/paclitaxel, carboplatin/paclitaxel, or cisplatin/docetaxel.
All patients completed ICT with acceptable toxicity (leukocytopenia grade 4: 8%). The remission rate of the primary tumor was 88% (22/25 patients). There was no need to delay CRT due to toxicity in any case. Each patient received the full radiation dose. Of the patients, 56% received >80% of the chemotherapy. The acute toxicity of CRT was moderate, no grade 4 toxicities occurred, while grade 3 toxicities included the following: infection (39%), dermatitis (13%), leukocytopenia (30%), and thrombocytopenia (4%). The local control rate was 84.6% ± 8.5% and the survival rate was 89.6% ± 7.2% at 12 months. Organ preservation was possible in 22/23 (95%) cases.
Short induction with a TP regimen and subsequent CRT with a taxan is feasible and associated with an encouraging local control rate.
Strahlentherapie und Onkologie 01/2011; 187(1):15-22. · 3.56 Impact Factor
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ABSTRACT: Synthetic glucagon-like peptide-1 (7-36)amide (GLP-1) lowers postprandial (pp) glycemia by stimulating insulin and inhibiting glucagon release and delaying gastric emptying (GE). However, the biological effects of the endogenous peptide and their relative contributions to pp glycemia remain to be defined in detail. Using the specific GLP-1 receptor antagonist exendin(9-39)amide [Ex(9-39)], we studied the exact impact of GLP-1 after an oral meal in humans.
After a 50-min basal period, 12 healthy subjects ingested a 412-kcal mixed semisolid meal containing 30 g oatmeal, labeled with 99mTc-Sn-colloid. GE was measured by high-resolution scintigraphy until 210 min after meal ingestion. In random order, saline or Ex(9-39) at 900 pmol/kg·min was infused iv. Additionally, in six subjects gastric motility was measured by antroduodenal manometry and a gastric barostat in parallel.
Ex(9-39) increased pp blood glucose excursions during the first 60 min after the meal (43.9 ± 5.4 vs. 35.9 ± 3.6 mg/dl, P = 0.008; pp peak glucose 154.0 ± 5.5 vs.141.0 ± 4.7 mg/dl, P = 0.009). Insulin increased slightly with Ex(9-39), whereas the insulin to glucose ratio was unchanged. pp glucagon was significantly increased with Ex(9-39) (7.5 ± 2.4 vs. 3.2 ± 2.1 pg/ml, P = 0.024). GE and accordingly gastric motility did not change with Ex(9-39). Multiple linear regression analysis revealed only changes of pp glucagon to be significantly associated with increased pp glycemia under Ex(9-39) (R = 0.678, P = 0.015).
Released after an oral meal, GLP-1 lowers pp glycemia. In this study, the inhibition of glucagon release was a major determinant of the acute GLP-1 action in healthy subjects. In contrast, gastric emptying was not changed by GLP-1 receptor antagonism.
The Journal of clinical endocrinology and metabolism 11/2010; 96(1):229-36. · 6.50 Impact Factor
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Burkhard S Kasper,
Tobias Struffert,
Ekkehard M Kasper,
Torsten Fritscher,
Elisabeth Pauli,
Daniel Weigel,
Frank Kerling,
Thilo Hammen,
Wolfgang Graf,
Torsten Kuwert,
Olaf Prante,
Bogdan Lorber,
Michael Buchfelder,
Arnd Doerfler,
Stefan Schwab,
Hermann Stefan, Rainer Linke
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ABSTRACT: Long-term epilepsy associated tumors (LEATs) are a frequent cause of drug-resistant partial epilepsy. A reliable tumor diagnosis has an important impact on therapeutic strategies and prognosis in patients with epilepsy, but often is difficult by magnetic resonance imaging (MRI) only. Herein we analyzed a large LEAT cohort investigated by 18fluoroethyl-L-tyrosine-positron emission tomography (FET-PET).
Thirty-six patients with chronic partial epilepsy and a LEAT-suspect MRI lesion were analyzed by FET-PET using visual inspection and quantitative analysis of standard uptake values (SUV). PET results were correlated with clinical and histopathologic data.
FET-PET study was positive in 22 of 36 analyzed lesions and in 14 of 22 histologically verified LEAT lesions. The precise World Health Organization (WHO) tumoral entity was not predicted by FET-PET. Notably, FET uptake correlated strikingly with age at epilepsy onset (p = 0.001). Further correlations were seen for age at surgery (p = 0.007) and gadolinium-contrast enhancement on MRI (p < 0.05).
FET-PET is a helpful tool for LEAT diagnosis, particularly when MRI readings are ambiguous. FET uptake, which is likely mediated by the l-amino acid transporter (LAT) family, might indicate a principally important biologic property of certain LEATs, since LAT molecules also are involved in cell growth regulation.
Epilepsia 10/2010; 52(1):35-44. · 3.96 Impact Factor
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ABSTRACT: Hybrid cameras that combine SPECT and helical CT can be used to correlate scintigraphic information with morphologic information in one imaging session. The purpose of this study was to investigate, in comparison with the value of scintigraphy and SPECT alone, the incremental diagnostic value of skeletal SPECT/CT in the care of patients with pain of the extremities.
Seventy-one patients without cancer who had pain in the extremities underwent three-phase bone scintigraphy and SPECT/CT of either the upper (n = 20) or the lower (n = 51) extremities. Planar scintigraphic and SPECT images and planar scintigraphic and SPECT/CT images were interpreted independently from each other. The findings were classified into the following diagnostic categories: normal, trauma, tumor, osteomyelitis, and osteoarthritis.
Four patients had no abnormal bone metabolism or CT abnormality in the extremities. Among 34 lesions classified as osteoarthritis on planar and SPECT images, seven were reclassified as fracture and one as benign tumor at SPECT/CT. Of 15 lesions initially classified as osteomyelitis, four were diagnosed as osteoarthritis, four as fracture, and one as inflammation of the soft tissue only. Of eight diagnoses of fracture with the conventional approach, two were reclassified as osteomyelitis and two as osteoarthritis. In one of 10 patients with the initial diagnosis of a tumorlike lesion, the diagnosis was changed to trauma on the basis of SPECT/CT findings, and in another patient, the diagnosis was changed to osteoarthritis. Overall, SPECT/CT findings led to revision of the diagnostic category in the cases of 23 of 71 patients (p < 0.01).
Compared with bone scintigraphy and SPECT, the use of SPECT/CT increases diagnostic accuracy in the evaluation of orthopedic disorders affecting the extremities.
American Journal of Roentgenology 04/2010; 194(4):W329-35. · 2.78 Impact Factor
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ABSTRACT: Hybrid imaging combining single photon emission computed tomography (SPECT) with (131)I and X-ray computed tomography (CT) performed at radioablation (RA) for thyroid carcinoma more accurately detects regional lymph node metastases (LNM) than does planar imaging. In this bicentric prospective study we used hybrid imaging in conjunction with histopathological examination to measure LNM frequency in a consecutive group of patients referred for RA due to stage T1 papillary thyroid carcinoma (PTC).
At the Departments of Nuclear Medicine of the Ludwig Maximilian University of Munich and the Friedrich Alexander University of Erlangen-Nuremberg SPECT/spiral CT is routinely performed in all PTC subjects at the time of RA. Screening of our SPECT/CT databases for PTC patients with T1 histology produced 98 patients from Munich and 53 patients from Erlangen, including 96 of 151 patients with microcarcinoma. In 69 patients of the entire group, cervical lymph node dissection had been performed, whereas nodal staging in the remaining 82 subjects was based on SPECT/CT.
LNM incidence in the whole group was 26% [95% confidence interval (CI): 20-33%] versus 22% (95% CI: 15-31%) in the microcarcinoma subgroup. SPECT/CT was more accurate in 24.5% of our patients than planar imaging with regard to nodal staging.
LNM occurs in one quarter of all patients with T1 PTC, and also in the subset with microcarcinoma. Performing (131)I SPECT/CT, either with therapeutic or diagnostic radioactivities, directly after thyroidectomy should provide more accurate staging of T1 PTC, thus facilitating optimal therapeutic management.
European Journal of Nuclear Medicine 04/2010; 37(8):1462-6. · 4.53 Impact Factor
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ABSTRACT: We report a case of a 53-year-old woman with ductal carcinoma in situ of the right breast. Skin-sparing mastectomy and single-stage reconstruction of the right breast with a "buried" free deep inferior epigastric perforator flap was performed. Classic clinical monitoring was not possible due to the buried situation of the free flap. To assess the perfusion and viability of the perforator based free flap we performed a Tc-99m-sestamibi-SPECT/CT. The results confirmed the intraoperative clinical findings. Tc-99m-sestamibi-SPECT/CT may be a new tool for the postoperative evaluation of regional perfusion and viability of buried perforator based free flaps.
Clinical nuclear medicine 01/2010; 35(1):36-7. · 3.92 Impact Factor
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ABSTRACT: In differentiated thyroid carcinoma (DTC), (131)I-SPECT/CT is more accurate in identifying radioiodine-positive lymph node metastases (LNM) than planar whole-body scans (WBS). The purpose of this study was to investigate the value of (131)I-SPECT/CT performed at the first radioablation to predict the occurrence and/or persistence of cervical radioiodine-positive LNM 5 months later.
The study included 81 DTC patients that had had SPECT/ spiral CT after radioablation of thyroid remnants after thyroidectomy. The patients were re-examined 5 months later using (131)I-WBS performed at TSH stimulation. In addition, SPECT/CT of the neck was performed in patients with iodine-positive cervical foci to distinguish between thyroid remnant and LNM. The outcome variable of the study was the detection or exclusion of iodine-positive cervical LNM.
Of 61 patients without a SPECT/CT diagnosis of (131)I-positive LNM at radioablation, 60 had no (131)I-positive LNM at follow-up. In the remaining patient of this group, a new radioiodine-positive LNM was detected. In 17 of 20 patients with a SPECT/CT diagnosis of (131)I-positive LNM (n = 19) or an indeterminate lesion (n = 1) at first radioablation, no (131)I-positive LNM were detected 5 months later. Radioiodine-positive LNM persisted in three patients of this group.
(131)I-SPECT/CT has a high negative predictive value with regard to the occurrence of radioiodine-positive cervical LNM 5 months after initial therapy. The majority of iodine-positive LNM diagnosed by SPECT/CT at radioablation disappear within 5 months. These findings motivate further research into the value of (131)I-SPECT/CT of the neck for predicting recurrence and planning surgical reintervention in DTC.
European Journal of Nuclear Medicine 11/2009; 37(4):699-705. · 4.53 Impact Factor
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ABSTRACT: To diagnose septic and aseptic loosening 18-fluorodeoxyglucose positron emission tomography ((18)F-FDG-PET) has been described with good results for hip arthroplasties. The purpose of the present study was to examine whether there is a difference of feasibility in detecting loosening of hip versus knee prostheses by use of (18)F-FDG-PET.
Thirty-two patients with lower limb arthroplasty complaints (74 components) were studied preoperatively with (18)F-FDG-PET. The interpretation of (18)F-FDG-PET was done according to evaluated criteria. The final diagnosis based on intraoperative findings in all cases including microbiological examinations.
For hip arthroplasty sensitivity/specificity of (18)F-FDG-PET towards implant loosening was 80%/87%. For infectious loosening of hip endoprostheses sensitivity/specificity was 67%/83%. In knee endoprostheses sensitivity/specificity for loosening was 56%/82% and 14%/89% for infection. The sensitivity of the results for knee and hip joints in regard to infectious versus aseptic loosening was significantly different.
We confirm that (18)F-FDG-PET is an appropriate tool to diagnose hip arthroplasty loosening. Differing from that (18)F-FDG-PET showed a significant lower sensitivity/specificity in detecting septic loosening of knee endoprostheses. It may therefore be necessary to use different methods to diagnose loosening of endoprostheses depending on the type of implant which is examined.
Archives of Orthopaedic and Trauma Surgery 11/2009; 130(10):1231-8. · 1.37 Impact Factor
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ABSTRACT: In about 40% of patients LEMS is not a paraneoplastic phenomenon (NT-LEMS). Several clinical aspects important to these patients remain open, especially the question when a LEMS can definitely be diagnosed as NT-LEMS. Here we describe a series of 25 German NT-LEMS patients regarding their clinical characteristics, duration of symptoms, value of serological markers, paraneoplastic antibodies and FDG-PET/CT. Furthermore, we discuss the current diagnostic criteria of NT-LEMS.
Journal of neuroimmunology 10/2009; 217(1-2):90-4. · 2.84 Impact Factor
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ABSTRACT: The aims of the present study were to check for metabolism of the bony segments of osteocutaneous free flaps that included lateral as well as medial scapular crests by 18F-fluoride positron emission tomography (PET)/computed tomography (CT) examinations and to assess donor site morbidity. Twenty patients were included in the study. In 10 patients, osteocutaneous free flaps were harvested that included lateral as well as medial scapular crests. Seven days after surgery, an 18F-fluoride PET/CT examination was performed to assess the metabolism and viability of the bony segments. In the additional 10 patients, flaps were harvested that only included the lateral scapular crest. All patients were asked to fill in the disabilities of the arm, shoulder, and hand (DASH) questionnaire 1 and 6 months after surgery. In the 10 free flaps that included lateral as well as medial scapular crests, 18F-fluoride PET/CT examinations revealed metabolism and viability of both bony segments. The DASH scores for the two patient groups did not differ significantly at 1 and 6 months after surgery (p(1 month) = 0.520, p(6 months) = 0.545). It seems that scapular osteocutaneous free flaps adopting lateral as well as medial scapular crests are a viable option for mandibular reconstruction and may be an alternative to the fibular double barrel.
Journal of Reconstructive Microsurgery 09/2009; 25(9):545-53. · 1.43 Impact Factor
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Melvin Samsom,
Adil Bharucha,
John E Gerich,
Kathrin Herrmann,
Jörg Limmer, Rainer Linke,
David Maggs,
Jörg Schirra,
Adrian Vella,
Hans-Jürgen Wörle,
Burkhard Göke
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ABSTRACT: It is long known that both type 1 and type 2 diabetes can be associated with changes in gastric emptying; a number of publications have linked diabetes to delayed gastric emptying of variable severity and often with poor relationship to gastrointestinal symptomatology. In contrast, more recent studies have reported accelerated gastric emptying when adjusted for glucose concentration in patients with diabetes, indicating a reciprocal relationship between gastric emptying and ambient glucose concentrations. This review proposes that gastroparesis or gastroparesis diabeticorum, a severe condition characterized by a significant impairment of gastric emptying accompanied by severe nausea, vomiting, and malnutrition, is often overdiagnosed and not well contrasted with delays in gastric emptying. The article offers a clinically relevant definition of gastroparesis that should help differentiate this rare condition from (often asymptomatic) delays in gastric emptying. The fact that delayed gastric emptying can also be observed in non-diabetic individuals under experimental conditions in which hyperglycaemia is artificially induced suggests that a delay in gastric emptying rate when blood glucose concentrations are high is actually an appropriate physiological response to hyperglycaemia, slowing further increases in blood glucose. The article discusses the strengths and weaknesses of various methodologies for assessing gastric emptying, especially with respect to the diabetes population, and reviews newer diabetes therapies that decelerate the rate of gastric emptying. These therapies may be a beneficial tool in managing postprandial hyperglycaemia because they attenuate rapid surges in glucose concentrations by slowing the delivery of meal-derived glucose.
Diabetes/Metabolism Research and Reviews 07/2009; 25(6):502-14. · 3.37 Impact Factor
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ABSTRACT: Standard magnetic resonance imaging (MRI) does not depict the true extent of tumour cell invasion in gliomas. We investigated the feasibility of advanced imaging methods, i.e. diffusion tensor imaging (DTI), fibre tracking and O-(2-[(18)F]-fluoroethyl)-L: -tyrosine ((18)F-FET) PET, for the detection of tumour invasion into white matter structures not visible in routine MRI.
DTI and fibre tracking was performed on ten patients with gliomas, WHO grades II-IV. Five patients experienced preoperative sensorimotor deficits. The ratio of fractional anisotropy (FA) between the ipsilateral and contralateral pyramidal tract was calculated. Twenty-one stereotactic biopsies from five patients were histopathologically evaluated for the absolute numbers and percentages of tumour cells. (18)F-FET PET scans were performed and the bilateral ratio [ipsilateral-to-contralateral ratio (ICR)] of (18)F-FET-uptake was calculated for both cross-sections of pyramidal tracts and biopsy sites.
The FA ratio within the pyramidal tract was lower in patients with sensorimotor deficits (0.61-1.06) compared with the FA ratio in patients without sensorimotor deficits (0.92-1.06). In patients with preoperative sensorimotor deficits, we found a significantly (p = 0.028) higher ICR of (18)F-FET uptake (1.01-1.59) than in patients without any deficits (0.96-1.08). The ICR of (18)F-FET-uptake showed a strong correlation (r = 0.696, p = 0.001) with the absolute number of tumour cells and a moderate correlation (r = 0.535, p = 0.012) with the percentage of tumour cells.
Our data show an association between preoperative sensorimotor deficits, increased (18)F-FET uptake and decreased FA ratio in the pyramidal tract. We demonstrated a correlation between tumour invasion and (18)F-FET uptake. These findings may help to distinguish between edema versus tumour-associated neurological deficits and could prevent the destruction of important structures, like the pyramidal tract, during tumour operations by allowing more precise preoperative planning.
Acta Neurochirurgica 06/2009; 151(9):1061-9. · 1.52 Impact Factor
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ABSTRACT: We report on a young lady suffering from adult neuroblastoma and anti-Hu associated paraneoplastic encephalomyelitis (PEM) with a tumour free survival of nine years up to now. Treatment included tumour surgery, radiation, high dose chemotherapy, and stem cell transplantation. Serological testing demonstrated a marked decline in anti-Hu antibody titres under therapy, and subsequent disappearance of the antibody 31 months after second tumour resection.
Journal of the neurological sciences 06/2009; 284(1-2):205-8. · 2.32 Impact Factor
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ABSTRACT: Slowing of gastric emptying by hyperglycemia, a physiological response to minimize postprandial hyperglycemia, may be impaired in patients with type 1 diabetes. The causes and consequences on glucose homeostasis are unknown.
Consequences of euglycemia- and hyperglycemia-induced changes in gastric emptying on postprandial glucose fluxes and excursions were studied in 10 healthy subjects and 15 type 1 diabetic subjects after ingestion of a mixed meal using the double isotope approach ([6,6-(2)H(2)] and [1-(13)C]glucose) and scintigraphic measurements of gastric emptying.
Gastric emptying was greater in type 1 diabetic subjects (90-120 min, P < 0.03), and 50% retention times were comparable in healthy subjects and type 1 diabetic subjects (167 +/- 8 vs. 152 +/- 10, P = 0.32). Hyperglycemia markedly delayed gastric emptying in healthy subjects but did not alter it in type 1 diabetic subjects (50% retention time 222 +/- 18 vs. 167 +/- 8 min, P = 0.003 and 148 +/- 9 vs. 152 +/- 10 min, P = 0.51). Plasma islet amyloid polypeptide (IAPP) increased approximately fourfold in healthy subjects (P < 0.001), whereas it was undetectable in type 1 diabetic subjects. IAPP replacement, using the analog pramlintide, in type 1 diabetic subjects slowed gastric emptying to a comparable extent, as did hyperglycemia in healthy subjects (P < 0.14), and greatly reduced postprandial hyperglycemia (P < 00.1). Meal-derived glucose appearance in plasma (10.7 +/- 0.5 vs. 6.8 +/- 0.7 mumol . kg(-1) . min(-1), P < 0.001) was reduced, and splanchnic glucose sequestration increased (14.0 +/- 3.0 vs. 25.0 +/- 6.0%, P = 0.04).
In patients with type 1 diabetes the ability to delay gastric emptying in response to hyperglycemia is impaired. This impairment contributes to exaggerated rates of meal-derived glucose appearance and, ultimately, postprandial glucose excursions.
Diabetes care 01/2009; 31(12):2325-31. · 8.09 Impact Factor
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ABSTRACT: The purpose of this study was to determine the diagnostic value of 131I SPECT/spiral CT (SPECT/CT) on nodal staging of patients with thyroid carcinoma at the first ablative radioiodine therapy.
Fifty-seven patients were studied using SPECT/CT 3-4 d after receiving 3.96+/-0.5 GBq of 131I for radioablation of thyroid remnants after a thyroidectomy for differentiated thyroid carcinoma. In addition to planar whole-body scintigraphy, SPECT/CT of the neck was performed using a hybrid camera combining a double-head SPECT camera with either a 2-slice (n=23) or a 6-slice (n=34) spiral CT scanner. The planar scans and the SPECT/CT images were evaluated for cervical tracer uptake independently of each other and of the clinical findings.
SPECT/CT led to a revision of the original diagnosis in 28 of 143 cervical foci of radioiodine uptake seen on planar imaging. In particular, SPECT/CT reclassified as benign 6 of 11 lesions considered to be lymph node metastases and 11 of 15 lesions considered to be indeterminate. Furthermore, SPECT/CT allowed the identification of 11 lymph node metastases classified as thyroid remnant or as indeterminate on planar imaging. Based on this revision, SPECT/CT yielded a gain in information on nodal stage in 20 of the 57 patients studied (35%, P<0.03). SPECT/CT altered nodal stage from N0 to N1 in 2 of 20 patients and from indeterminate (Nx) to N1 in 6 of 30 patients. The result was a change in risk stratification conforming to the classification proposed by the International Union Against Cancer in 14 patients (25%).
SPECT/CT determines lymph node involvement at radioablation performed for thyroid cancer more accurately than does planar imaging. SPECT/CT may alter management in roughly one quarter of patients with thyroid carcinoma by upstaging or downstaging their disease.
Journal of Nuclear Medicine 12/2008; 50(1):18-23. · 6.38 Impact Factor
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ABSTRACT: The aim of this study was to determine the spatial correlation of O-(2-(18)F-fluoroethyl)-L-tyrosine ((18)F-FET) uptake and the concentrations of choline (Cho), creatine (Cr), and total N-acetylaspartate (tNAA) determined with proton magnetic resonance spectroscopic imaging ((1)H MRSI) in cerebral gliomas for the multimodal evaluation of metabolic changes.
(18)F-FET PET and 2-dimensional (1)H MRSI were performed in 15 patients with cerebral gliomas of World Health Organization (WHO) grades II-IV. PET and (1)H MRSI datasets were coregistered by use of mutual information. On the basis of their levels of (18)F-FET uptake, 4 different areas in a tumor (maximum, strong, moderate, and low (18)F-FET uptake) were defined on PET slices as being congruent with the volume of interest in the (1)H MRSI experiment. (18)F-FET uptake in lesions was evaluated as tumor-to-brain ratios. Metabolite concentrations for Cho, Cr, and tNAA and Cho/tNAA ratios were computed for these 4 areas in the tumor and for the contralateral normal brain.
In the area with maximum (18)F-FET uptake, the concentration of tNAA (R= -0.588) and the Cho/tNAA ratio (R=0.945) correlated significantly with (18)F-FET uptake. In the areas with strong and moderate (18)F-FET uptake, only the Cho/tNAA ratios (R=0.811 and R=0.531, respectively) were significantly associated with amino acid transport. At low (18)F-FET uptake, analysis of the correlations of amino acid uptake and metabolite concentrations yielded a significant result only for the concentration of Cr (R=0.626). No correlation was found for metabolite concentrations determined with (1)H MRSI and (18)F-FET uptake in normal brain tissue. Maximum (18)F-FET uptake and the tNAA concentration were significantly different between gliomas of WHO grades II and IV, with P values of 0.032 and 0.016, respectively.
High (18)F-FET uptake, which is indicative of tumor cell infiltration, associates with neuronal cell loss (tNAA) and changes in ratios between parameters representing membrane proliferation and those of neuronal loss (Cho/tNAA ratio), which can be measured by (1)H MRSI. The significant correlation coefficients detected for Cr in regions with low (18)F-FET uptake suggests an association between the mechanism governing amino acid transport and energy metabolism in areas that are infiltrated by tumor cells to a lesser extent. These findings motivate further research directed at investigating the potential of (1)H MRSI to define tumor boundaries in a manner analogous to that of amino acid PET.
Journal of Nuclear Medicine 06/2008; 49(5):721-9. · 6.38 Impact Factor
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ABSTRACT: Bone scintigraphy, although quite sensitive to detect skeletal lesions, has a comparatively low specificity. Hybrid-cameras
combining single-photon emission computed tomography (SPECT) and spiral-CT offer the opportunity to correlate scintigraphic
information with high-quality visualization of morphology in one session. This may lead to an improvement in diagnostic accuracy
and anatomic lesion localization. We present 11 patients, who underwent SPECT/CT of the feet (n=10) and hands (n = 1). The
examinations were performed due to pain in foot or hand with the following suspected clinical diagnoses: arthrosis (n=1);
fracture (n=3); osteomyelitis (n=4); reflex dystrophia (n=1); and, pain of unclear origin (n=2). All patients underwent SPECT/CT
hybrid imaging using a dual-headed SPECT camera integrated with a 2-slice spiral CT scanner in one gantry. SPECT, CT, and
SPECT/CT were evaluated independently from each other with respect to main diagnosis, anatomic lesion localization, and detection
of a possible additional diagnosis. SPECT/CT improved lesion localization in 8 of 11 patients (73%) in comparison to SPECT
alone, and in 4 of 11 patients (36%) in comparison to CT alone. Diagnostic accuracy was improved in 4 of 11 patients (36%)
in comparison to either SPECT or CT alone. In conclusion, skeletal SPECT/CT improves diagnostic accuracy and lesion localization
of orthopedic disorders in the feet and hands. The obtained results encouraged extensive studies to further investigate the
potential gain in diagnostic accuracy brought about by SPECT/spiral-CT hybrid imaging in orthopedic disorders of the peripheral
extremities.
Central European Journal of Medicine 11/2007; 2(4):499-510. · 0.31 Impact Factor
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ABSTRACT: To evaluate whether gastric scintigraphy with quantitative analysis of gastric peristalsis may be a useful tool for documenting the effects of prokinetic therapy.
Gastric emptying was determined in eight patients with insulin dependent diabetes mellitus (IDDM) and nine patients with progressive systemic sclerosis (PSS) after ingestion of a semi-solid test meal. Fourier analysis of condensed images was used to evaluate contraction amplitudes of the entire stomach, as well as frequency and velocity of gastric contractions. Patients were studied twice, first under baseline conditions and then after 4 weeks of continuous oral prokinetic therapy with cisapride (10 mg t.i.d.). Findings were compared with data derived from 15 healthy controls.
At baseline conditions IDDM and PSS patients exhibited reduced gastric peristalsis and delayed emptying compared to controls. After 4 weeks of prokinetic treatment, gastric contraction amplitudes increased significantly, especially in the gastric corpus and the proximal stomach, associated with a slight improvement of gastric emptying. Changes in frequency and velocity of gastric contractions during prokinetic treatment correlated with the improvement of gastric motility and emptying.
Prokinetic therapy with cisapride stimulates gastric motility, and could be non-invasively monitored by scintigraphy. This radionuclide technique provides a number of relevant parameters of gastric function, such as gastric emptying, contraction amplitudes, frequency and velocity of gastric contractions, which give crucial insights into the mechanisms of action of prokinetic drugs.
Nuclear Medicine Communications 07/2005; 26(6):527-33. · 1.40 Impact Factor
