-
B Diehl,
I Najm,
E LaPresto,
R Prayson,
P Ruggieri,
A Mohamed,
Z Ying, M Lieber,
T Babb,
W Bingaman,
H O Lüders
[show abstract]
[hide abstract]
ABSTRACT: Recent MRI-based volume reconstruction studies in intractable temporal lobe epilepsy (TLE) due to hippocampal sclerosis (HS) suggested atrophy that extends to the adjacent neocortical areas.
To study the extent of temporal lobe volume (TLV) abnormalities in patients with pathologically confirmed HS (with or without cortical dysplasia [CD]) who underwent anterior temporal lobectomy for the treatment of drug-resistant TLE.
Fifty patients (right TLE: n = 24; left TLE: n = 26) were found to have HS (hippocampal cell loss of >30%). Associated neocortical CD was seen in 20 patients (43%). MRI-based TLVs and hippocampal and hemispheric volume reconstructions in all patients were compared between pathologic groups and with volumes acquired from 10 age-matched control subjects.
TLVs ipsilateral to the epileptogenic zone in patients with TLE were smaller than TLVs in control subjects (p < 0.01). In patients with left TLE, TLVs ipsilateral to the epileptogenic zone were smaller than contralateral TLVs (left: 66.6 +/- 8.3 cm3, right: 74.9 +/- 10.0 cm3; p < 0.001). In patients with right TLE, there were no significant asymmetries. The contralateral TLVs (regardless of the side of surgery) were smaller in the HS + CD group than the HS group (HS + CD group: 74.9 +/- 8.6 cm3, HS group: 79.7 +/- 6.6 cm3; p < 0.05). Patients with HS + CD had a tendency to have less hippocampal atrophy and slightly smaller TLVs ipsilateral to the epileptogenic zone, accounting for significantly smaller TLV/hippocampal volume ratios compared with patients with HS alone.
Drug-resistant TLE due to HS is associated with extrahippocampal temporal lobe atrophy. The presence of bilateral temporal lobe atrophy is suggestive of a more widespread (bilateral) temporal lobe involvement in patients with HS and CD.
Neurology 05/2004; 62(10):1729-35. · 8.31 Impact Factor
-
B Diehl,
I Najm,
P Ruggieri,
J Tkach,
A Mohamed,
H Morris,
E Wyllie,
E Fisher,
J Duda, M Lieber,
W Bingaman,
H O Lüders
[show abstract]
[hide abstract]
ABSTRACT: Diffusion-weighted MR imaging (DWI) is a novel technique to delineate focal areas of cytotoxic edema of various etiologies. We hypothesized that DWI may also detect the epileptogenic region and adjacent areas during the ictal and early postictal periods in patients with temporal lobe epilepsy (TLE).
We studied patients with intractable TLE (n = 9), due to hippocampal sclerosis (HS, n = 7), left mesial temporal lobe tumor (n = 1), and of unknown etiology (n = 1). Informed consent was obtained before inclusion in the study. All patients with single short seizures were scanned immediately after EEG-documented seizures (between 45 and 150 min); one of two patients in status was scanned 14 h after cessation of seizures. DWI results were analyzed visually and by calculating apparent diffusion coefficient (ADC) maps.
We found significant decreases in ADC postictally in one of six patients with TLE due to HS and single short seizures. One patient with an incompletely resected temporal lobe tumor also exhibited ADC abnormalities. One patient in focal status epilepticus revealed a decrease in ADC, and one patient with a continuous aura had no DWI abnormality.
Postictal DWI technique may occasionally help delineate epileptic areas in some patients with TLE. Yield is low in patients with HS and single short seizures: it may be higher in patients with tumor or status epilepticus.
Epilepsia 02/2001; 42(1):21-8. · 3.96 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: We sought to determine if dedicated gastrointestinal technologists could be trained to properly perform esophagography and double-contrast barium enema examinations.
Ninety-four patients undergoing double-contrast barium enema examinations and 123 patients undergoing esophagographic examinations were included in the study. The study was conducted over a 4-month period, with examinations performed by eight gastrointestinal technologists, 10 radiology residents, and four staff radiologists. Four random lists were generated for each set of examinations. Each staff gastrointestinal radiologist, who was unaware of who had performed the examination, independently scored the representative radiographs.
For the double-contrast barium enema examinations, no statistically significant differences were found between the technologists and residents for amount of barium used, degree of distention, cecal opacification, and quality of spot radiographs. The technologist-performed examinations had a statistically significant lower mean fluoroscopy time (3.2 min, compared with 4.0 min for staff radiologists and 5.7 min for residents). For the esophagrams, no statistically significant differences between technologists and residents were found for single-contrast esophagrams; radiographs of the gastric cardia; assessment of motility, reflux, and transit of a solid bolus; and fluoroscopy time. Double-contrast esophagrams obtained by technologists received a better mean score than did those of the residents.
Radiology technologists can be trained to perform high-quality esophagography and double-contrast barium enema examinations without an unacceptably high radiation dose.
American Journal of Roentgenology 12/2000; 175(5):1449-52. · 2.78 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: There is a need for reliable monitoring of workforce trends in the field of pediatric radiology by the Society for Pediatric Radiology. In addition, the Society should periodically assess itself as to its mission and relevance to its members via membership surveys.
The Membership Committee of the Society for Pediatric Radiology, 1999, conducted a 54-question survey to determine the makeup of its members, job profiles, satisfaction with services of the Society for Pediatric Radiology, and its official journal, Pediatric Radiology.
Seven hundred fifty surveys were given to active members of the Society for Pediatric Radiology in the United States and Canada. There were 275 surveys returned for an overall response of 37%.
Mean age of members is 48 years with 99% of respondents working. Membership is 34% female and 66% male. Women members of the Society are younger (45 vs 49 years, P = 0.0012) and work less hours (47.8 vs 51.0, P = 0.0135) than men. Fifty-seven percent of respondents practice in a freestanding children's hospital, 29% in a "children's hospital within a hospital," and 14% are in community hospitals or an office-based practice. Eighty-two percent of the responding pediatric radiologist's time is spent in performing examination on children, with only 18% spent on adult work or administration. Forty-eight percent work at more than one office. Sixty-one percent worked evenings or weekends, excluding night call. Two hundred twenty-two of 275 respondents had received a Certificate of Added Qualification. The meeting "for CME credit" was considered the most important benefit of Society membership. Most respondents read select articles in Pediatric Radiology. There was sentiment to decrease esoteric case reports in favor of review articles. Only 19% of respondents submitted their articles to Pediatric Radiology initially.
Pediatric radiologists are a diverse membership with the common goal of advocating for healthcare and imaging in children. Survey information given to the leadership of the Society will help the organization remain responsive to its members.
Pediatric Radiology 10/2000; 30(9):581-5; discussion 585-6. · 1.67 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Background. There is a need for reliable monitoring of workforce trends in the field of pediatric radiology by the Society for Pediatric
Radiology. In addition, the Society should periodically assess itself as to its mission and relevance to its members via membership
surveys.¶Objective. The Membership Committee of the Society for Pediatric Radiology, 1999, conducted a 54-question survey to determine the makeup
of its members, job profiles, satisfaction with services of the Society for Pediatric Radiology, and its official journal,
Pediatric Radiology.¶Materials and methods. Seven hundred fifty surveys were given to active members of the Society for Pediatric Radiology in the United States and
Canada. There were 275 surveys returned for an overall response of 37 %.¶Results. Mean age of members is 48 years with 99 % of respondents working. Membership is 34 % female and 66 % male. Women members
of the Society are younger (45 vs 49 years, P = 0.0012) and work less hours (47.8 vs 51.0, P = 0.0135) than men. Fifty-seven percent of respondents practice in a freestanding children's hospital, 29 % in a “children's
hospital within a hospital,” and 14 % are in community hospitals or an office-based practice. Eighty-two percent of the responding
pediatric radiologist's time is spent in performing examination on children, with only 18 % spent on adult work or administration.
Forty-eight percent work at more than one office. Sixty-one percent worked evenings or weekends, excluding night call. Two
hundred twenty-two of 275 respondents had received a Certificate of Added Qualification. The meeting “for CME credit” was
considered the most important benefit of Society membership. Most respondents read select articles in Pediatric Radiology. There was sentiment to decrease esoteric case reports in favor of review articles. Only 19 % of respondents submitted their
articles to Pediatric Radiology initially.¶Conclusion. Pediatric radiologists are a diverse membership with the common goal of advocating for healthcare and imaging in children.
Survey information given to the leadership of the Society will help the organization remain responsive to its members.
Pediatric Radiology 01/2000; 30(9):581-586. · 1.67 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: To evaluate the effectiveness of the Cragg thrombolytic brush catheter for declotting of synthetic arteriovenous dialysis shunts.
In this randomized controlled trial, 77 patients with synthetic forearm loop shunts that were thrombosed were randomly assigned to undergo pharmacomechanical thrombolysis with a pulsed spray (n = 34) or a thrombolytic brush catheter (n = 43). The following findings were evaluated: declotting time, urokinase dose, procedure time, complications, and shunt patency at the first dialysis session and at 3 months. All data were collected prospectively in an unblinded manner.
The total amount of urokinase used, including secondary interventions, was 243,657 IU with the catheter versus 476,563 IU with the pulsed spray (P = .001). At 15 minutes, clot lysis was successful in 66% of the patients with the catheter versus in 19% with the pulsed spray (P = .001). At 30 minutes, clot lysis was successful in 98% with the catheter versus 47% with the pulsed spray (P = .001). Procedure complication rates and patency at 3 months were similar for the catheter and the pulsed-spray groups.
Use of the Cragg catheter with urokinase offered faster and more complete clot lysis than did use of the pulsed spray with urokinase. The amount of urokinase used with the catheter was half that used with the pulsed spray. Shunt patency at 3 months was similar for the two treatment methods.
Radiology 11/1999; 213(1):180-4. · 5.73 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: The in vivo radiographic features of two commercially available formulations of barium used as contrast media in dedicated small-bowel series were compared.
Fifty-six consecutive outpatients referred for a dedicated small-bowel series were randomly administered either E-Z-Paque or Entrobar. Representative survey radiographs from each examination were randomized and reviewed by six gastrointestinal radiologists from three institutions. Each observer assigned a numeric score (1 = poor, 2 = fair, 3 = good, and 4 = excellent) that rated the quality of the radiograph with respect to these characteristics: definition of fold pattern, translucency, distention, and integrity of the barium column. Statistical analysis was performed for each characteristic using Wilcoxon's two-sample rank sum test.
All six observers found a statistically significant difference between the two barium formulations for mean scores for definition of fold pattern and translucency. Mean scores for fold pattern were 3.3, 3.0, 3.2, 3.6, 3.3, and 3.4 for Entrobar and 2.1, 2.3, 2.4, 3.2, 2.6, and 2.7 for E-Z-Paque. Mean scores for translucency were 2.5, 2.7, 2.8, 3.1, 2.7, and 3.3 for Entrobar and 1.6, 1.7, 2.1, 2.3, 1.9, and 2.7 for E-Z-Paque. No statistically significant difference was found for mean score for distention or integrity of the barium column.
On radiographs, Entrobar was found to have superior characteristics for visualization of fold pattern and translucency but offered no advantages for distention or integrity of the barium column. Improved translucency and definition of fold pattern may translate into improved sensitivity and confidence in diagnosing small-bowel abnormality.
American Journal of Roentgenology 03/1999; 172(2):379-82. · 2.78 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: The purpose of this study was to subjectively compare the visibility of normal anatomy of the hands and feet using selenium-based digital radiography versus conventional film-screen (100-speed) radiography.
Digital and film-screen images of the hands and feet of 24 patients were obtained without an antiscatter grid using identical X-ray exposure. Each pair of images was evaluated independently by five experienced radiologists for visibility of normal anatomy using a six-point rating scale. Soft tissues, cortical bone, and trabeculae were evaluated. For each observer, "equivalence" was defined as a mean difference in image quality of less than 1 unit on the 0-5 scale used in the study. Paired t tests were also performed to determine whether the average visibility rating of one technique was statistically superior to that of the other at a .05 level of significance for each observer and at each anatomic landmark.
In all categories, selenium-based digital images were rated equivalent to film-screen images by the five observers. Using the sum of the nine landmarks, four of the five observers rated the quality of selenium-based digital images superior to that of film-screen images.
Subjective visibility of normal anatomy of the hands and feet using selenium-based digital radiography was similar to that achieved using conventional film-screen radiography.
American Journal of Roentgenology 02/1999; 172(1):177-84. · 2.78 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: 123I/99mTc-sestamibi subtraction single photon emission computed tomography (SPECT) has been proposed to detect hyperplastic parathyroid tissue, but the clinical usefulness of this technique in secondary hyperparathyroidism is uncertain. The purpose of this study was to evaluate preoperative parathyroid localization using 123I/99mTc-sestamibi subtraction SPECT in patients with renal failure and secondary hyperparathyroidism. Nineteen patients with chronic renal failure and secondary hyperparathyroidism underwent 123I/99mTc-sestamibi subtraction SPECT imaging preoperatively. None of these patients had undergone previous neck surgery. The location, weight, and histopathological results of all identified parathyroid glands were recorded. Surgery was considered successful in all patients, with resection of a total of 74 hyperplastic parathyroid glands. 123I/99mTc-sestamibi subtraction SPECT correctly identified 57 of these parathyroid glands (77% sensitivity). The mean weight among the true positive glands (n = 57) was 1031 mg (range, 45-7900 mg), and that among the false negative glands (n = 17) was 465 mg (range, 20-1800 mg). This difference between the mean weights was statistically significant (P = 0.018). There was a positive correlation between parathyroid weight and detectability with 123I/99mTc-sestamibi subtraction SPECT (Spearman correlation = 0.28; P = 0.0167). 123I/99mTc-sestamibi subtraction SPECT is able to correctly localize hyperplastic parathyroid glands in patients with renal failure and secondary hyperparathyroidism, but there is a fairly weak relationship between preoperative detection rate and anatomical parathyroid gland size.
Journal of Clinical Endocrinology & Metabolism 12/1998; 83(11):3867-71. · 6.50 Impact Factor
-
Journal of Digital Imaging 09/1998; 11(3 Suppl 1):172-3. · 1.25 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: To implement and assess the application of segmented three-dimensional echo-planar MR imaging time-of-flight flow sequences for studying the anatomy of the cervical carotid arteries at 1.5 T.
The 3-D echo-planar sequences were segmented along the in-plane phase-encoding direction. Echo train lengths (ETLs) of 3 and 5 and signal bandwidths of +/-25, +/-33, and +/-50 KHz were tested along with a conventional (ETL = 1) 3-D MR flow study in six healthy volunteers and in five patients with known arteriosclerotic disease involving the carotid bifurcation as confirmed by conventional angiography. The volunteer data were used to rank the techniques with respect to vessel dimension, vessel/background contrast, and quality by four trained neuroradiologists. For the patient studies, the percentage of stenoses was measured for all MR studies and compared against the conventional angiographic data using the criteria of the North American Symptomatic Carotid Endarterectomy Trial.
Using Wilcoxon's test statistic and a significance level of .05, we found that the conventional MR flow examination was better than the segmented techniques and that the segmented techniques with ETL of 3 were superior to their counterparts with ETL of 5. For the ETL of 3 techniques, the high-bandwidth studies were inferior to their lower bandwidth counterparts; however, there was no significant difference between the performance of the medium- and low-bandwidth sequences. The patient data revealed that the segmented techniques consistently overestimated the severity of stenosis; however, in no instance did any of the segmented examinations erroneously indicate the presence of disease.
The reduction in acquisition time and the zero false-positive rate we obtained suggest that segmented 3-D echo-planar MR flow techniques may be used as a screening/locating study for cervical carotid artery disease.
American Journal of Neuroradiology 09/1997; 18(7):1339-47. · 2.93 Impact Factor
-
J Perl,
J A Tkach,
M Porras-Jimenez, M Lieber,
N Obuchowski,
J S Ross,
X P Ding,
P M Ruggieri,
D M Shearer,
K Khajavi,
T J Masaryk
[show abstract]
[hide abstract]
ABSTRACT: The treatment algorithm for acute cerebrovascular accidents has traditionally sorted these accidents as either hemorrhagic or nonhemorrhagic, and MR imaging, with its ability to allow expeditious assessment of vascular substrates and regional blood volume, is well suited for this purpose. Our purpose was to delineate the accuracy of MR imaging in acute, hemorrhagic forms of stroke during the time frame considered beneficial for intervention in an animal model.
Eighteen dogs with small, iatrogenic parenchymal, subarachnoid hemorrhage (SAH), or both were serially scanned over the initial 6-hour postictal period. Confirmatory pathologic specimens and 3-hour postictal CT scans were obtained in all animals. The MR and CT studies were then interpreted in a blinded fashion by two neuroradiologists for the presence of hemorrhage. The results were subjected to receiver operating characteristic analysis.
MR imaging depicted acute parenchymal hemorrhage and SAH with a high degree of accuracy at 1.5 T. This finding was independent of each of the time points studied during the 6-hour window. For SAH, the MR accuracy for reader 1 was 0.86 (95% CI, 0.76-0.97); for reader 2, accuracy was 0.85 (95% CI, 0.71-0.99). The CT accuracy for the two readers was 0.42 (95% CI, 0.26-0.58) and 0.66 95% CI, 0.43-0.89), respectively. Fluid-attenuated inversion-recovery images improved the conspicuity of SAH on MR images and, along with spin-density-weighted spin-echo sequences, helped to establish the hemorrhagic nature. For parenchymal hemorrhage, the MR accuracy for reader 1 was 0.90 (95% CI, 0.81-0.99); for reader 2, accuracy was 0.93 (95% CI, 0.84-1.00). With CT, the accuracy of reader 1 was 0.91 (95% CI, 0.85-0.97) whereas for reader 2 accuracy was 0.76 (95% CI, 0.69-.83). Parenchymal hemorrhage detection and diagnosis was best with T2*-weighted gradient-echo images.
MR imaging with appropriately selected sequences appears able to provide information regarding the presence (or absence) of hemorrhage in an acute stroke model requisite to the initiation of treatment.
American Journal of Neuroradiology 20(10):1863-70. · 2.93 Impact Factor
