High Prevalence of Dysplastic Development of Sacral Vertebral Arches in Pediatric Enuresis.

PURPOSE: This is the first report to compare 3-dimensional computed tomography (3D-CT) images between pediatric patients with enuresis and children without lower urinary tract symptoms who underwent pelvic CT for other reasons. METHODS: Forty-seven children (33 boys and 14 girls) with primary enuresis underwent 3D-CT of sacrococcygeal bones. The control group consisted of 138 children (78 boys and 60 girls) who underwent pelvic CT for other reasons. First, we determined the presence or absence of unfused sacral arches at the L4-S3 levels in both cohorts. Subsequently, we compared the fusion of sacral arches in age- and sex-matched children from these 2 groups. RESULTS: Dysplastic sacral arches, characterized by lack of fusion at 1 or more levels of the S1-3 arches, were observed in nearly all patients in the enuresis group. In the control group (n=138), 54 of 79 children over 10 years old (68%) exhibited fused sacral arches at 3 S1-3 levels. All 11 control children under 4 years old displayed at least 2 unfused sacral arches at the S1-3 levels. In a comparative study of age- and sex-matched patients with enuresis and control children aged 5 to 13 years (n=32 for each group, with 21 boys and 11 girls; mean age, 8.0±2.2 years [range, 5-13 years]), only 1 patient (3%) in the enuresis group exhibited fusion of all S1-3 arches. In contrast, 20 of 32 control group participants (63%) had 3 fused sacral arches (P<0.0001). CONCLUSION: Sacral vertebral arches typically fuse by the age of 10 years. However, in this study, children with enuresis exhibited a significantly elevated prevalence of unfused sacral arches, suggesting that dysplastic development of sacral vertebral arches may play a pathological role in enuresis.

Deep venous thrombosis: diagnostic value of non-contrast-enhanced MR venography using electrocardiography-triggered three-dimensional half-Fourier FSE.

We prospectively assessed the diagnostic accuracy of non-contrast-enhanced MR venography using both the flow-refocused fresh-blood imaging (FR-FBI) and the swap phase-encode arterial double-subtraction elimination (SPADE) techniques for detecting deep vein thrombosis (DVT), as compared using conventional X-ray venography as the reference standard. Forty-one legs of 32 consecutive patients (eight men, 24 women; mean age +/- standard deviation, 69.4 +/- 15.3 years) suspected of having deep vein thrombosis and thus examined using conventional X-ray venography underwent MR FR-FBI and SPADE. Twenty-five of the 32 patients had nonmagnetizing, metal implants they had received during hip or leg surgery. Two radiologists independently assessed the MR venograms as either diagnostic or nondiagnostic and with either the presence or absence of thrombi. The sensitivities of FR-FBI and SPADE for diagnosing thrombus were 100% (53 of 53) for both reviewers. Nondiagnostic segments were excluded from this analysis. The corresponding specificities were 100% (238 of 238 for reviewer A) and 99.6% (237 of 238 for reviewer B). The interobserver agreement regarding the MR images for the assessment of thrombosis was high (kappa = 0.92). Non-contrast-enhanced MR venography using SPADE and FR-FBI is highly accurate and reproducible for diagnosing DVT. This is especially advantageous for patients who have received nonmagnetizing, metal implants during orthopedic surgery.

Deep vein thrombosis using noncontrast-enhanced MR venography with electrocardiographically gated three-dimensional half-Fourier FSE: preliminary experience.

Three noncontrast-enhanced MR venography techniques are presented for assessing deep vein thrombosis (DVT) at 0.5 T in patients with metallic implants. Two cardiac-gated 3D half-Fourier FSE fresh blood imaging sequences with flow-refocusing pulses (FR-FBI) in the read-out (RO) direction and without FR pulses (non-FR-FBI) were developed for slower-flowing blood. For faster flowing blood, a swap phase-encode arterial double-subtraction elimination (SPADE) technique was developed. The three techniques were assessed both quantitatively using signal-to-noise (SNR) and contrast-noise-ratio (CNR) measurements and qualitatively by subjective image analysis in 15 volunteers. SPADE was compared to FR-FBI in the pelvic veins and FR-FBI was compared to non-FR-FBI in the thigh and calf veins. Both SPADE and FR-FBI techniques produced significantly higher SNRs, CNRs, and image quality in each comparative study (P<0.001). Five patients with metallic implants and confirmed DVT underwent SPADE (pelvic veins) and FR-FBI (thigh and calf veins) examinations and the results were compared to conventional venography. The SPADE and FR-FBI images showed all DVTs from all five patients without interference from implant susceptibility artifacts. The excellent image quality produced by both SPADE and FR-FBI throughout peripheral vasculature demonstrates their promise for detecting DVT in postsurgery patients.

Dual-time-point F-18 FDG PET/CT for evaluation in patients with malignant lymphoma.

OBJECTIVE: The aim of this study was to evaluate the usefulness of F-18 fluorodeoxyglucose (FDG) dual-time-point (DTP) positron emission tomography (PET)/computed tomography (CT) with semiquantitative analyses for the initial staging in patients with malignant lymphoma. METHODS: Forty-three patients had DTP PET/CT, with 60-min and 2-h scan [n = 8, Hodgkin's lymphoma (HL); n = 12, indolent non-Hodgkin lymphoma (NHL); n = 23, aggressive NHL]. RESULTS: A total of 524 lesions were evaluated (406 lymph nodes and 118 extra-nodal lesions). The maximum standardized uptake value (SUV(max)) on 2-h delayed scan (SUV(2)) was significantly higher than those on 1-h early scan (SUV(1)) for all groups (P < 0.0001 for HL; P < 0.0001 for indolent NHL; P < 0.0001 for aggressive NHL). Significant differences were detected between HL and indolent NHL, between indolent NHL and the aggressive NHL for both SUV(1) and SUV(2) (each P < 0.0001). No significant differences were detected between HL and aggressive NHL for both SUV(1) and SUV(2) (P = 0.6891 for SUV(1); P = 0.8828 for SUV(2)); however, significant differences were detected for the retention index of SUV(max) between these groups (P = 0.0238). CONCLUSIONS: DTP F-18 FDG PET/CT with a semiquantitative technique may have the potential to provide the more accurate diagnoses for the staging of malignant lymphoma and the more important role in predicting the histological grades of malignancy compared with single-time-point F-18 FDG-PET scan.