CONCLUSION. Hirschsprung's disease is rare in girls and bilateral hydrosalpinx is also extremely uncommon in sexually inactive adolescents. We think there may be a possible common cause: either a postsurgical complication or a congenital defect of the autonomous innervation in the context of a neurocristopathy. Because of the rarity of both conditions, the association is unlikely to be coincidental. The cause of this association is unclear and further studies are required to find its prevalence and to estimate the possible impact on fertility.

CONCLUSION. We provide important guidelines and key examples that will help readers perform percutaneous needle bone biopsy safely.

CONCLUSION. In all three patients, more than 100 liver adenomas revealed no metabolism of the new liver-specific contrast agent in the delayed phase. Because of absent or strongly reduced intracellular uptake of gadoxetic acid in all adenomas during delayed contrast-enhanced series, differentiation of adenomas from dysplastic or malignant lesions was not possible.

CONCLUSION. Cardiac MDCT provides an excellent imaging method for illustrating cardiac valve disease. Radiologists should be aware of the various appearances of the common and most important cardiac valve diseases on cardiac MDCT.

CONCLUSION. Neuroimaging advances have improved the diagnosis of tuberous sclerosis complex and the treatment of children with this condition. Superimposition of functional information from PET onto MRI allows accurate and noninvasive identification of epileptogenic tubers, improving surgical cure rates. Magnetic source imaging can also be used to localize epileptiform activity arising from tubers.

CONCLUSION. Percutaneous CT-guided aspiration is an effective method for the management of lumbar intervertebral discal cysts.

CONCLUSION. By considering the applications of these principles and the stereotypical ways in which humans perceive visual stimuli, a radiology learner may incur fewer errors of diagnosis. This article serves to introduce several important principles of Gestalt theory, identify examples of these principles in widely recognizable fine art, and highlight their implications for radiology education.

MATERIALS AND METHODS. A computer search of abdominal CT reports using the term "adrenal" was performed in 65,231 consecutive patients with examinations performed from January 2000 to December 2003. An adrenal mass was identified in 3,307 (5%) patients. Patients with no known malignancy and no suspicion for a hyperfunctioning adrenal mass were further isolated. Nine hundred seventy-three patients with 1,049 adrenal masses fulfilled the study criteria. The nature of each lesion was determined by histopathology; imaging characterization with CT, MRI, or washout; a minimum of 1 year of stability on follow-up imaging; or clinical follow-up of at least 2 years.

RESULTS. One thousand forty-nine adrenal masses were characterized with the following methods: histopathology (n = 12), imaging characterization (n = 909), imaging follow-up (n = 87), and clinical follow-up (n = 41). There were 788 adenomas constituting 75% of all lesions. There were 68 myelolipomas (6%), 47 hematomas (4%), and 13 cysts (1%). Three pheochromocytomas (0.3%) and one cortisol-producing adenoma (0.1%) were found incidentally. One hundred twenty-eight lesions (12%) were presumed to be benign by imaging or clinical stability. No malignant adrenal masses were found, even among the 14 patients who later developed malignancy elsewhere.

CONCLUSION. In 973 consecutive patients with an incidental adrenal mass and no history of cancer, no malignant lesions were identified. Adenomas (75%) and myelolipomas (6%) were the most common lesions.

MATERIALS AND METHODS. Twenty urinary stones of different sizes (1.4–4.2 mm in short-axis diameter) were placed in plastic containers. The containers were consecutively filled with different concentrations of iodine solution (21, 43, 64, 85, and 107 mg/dL; CT attenuation value range, 510–2,310 H at 120 kVp). Dual-energy CT was repeated with 80–140 and 100–140 kVp pairs, two collimation–slice thickness combinations, and the presence or absence of a 4-cm-thick oil gel around the phantom. The iodine-subtraction virtual unenhanced images were reconstructed using commercial software. The images were evaluated by three radiologists in consensus for the visibility of the stones and the presence of residual nonsubtracted iodine. Stone visibility rates were compared between the 80–140 and 100–140 kVp pairs and the five different iodine concentrations.

RESULTS. Stone visibility rates with the 80–140 kVp pair were 99%, 93%, 96%, 94%, and 3% and those with the 100–140 kVp pair were 98%, 95%, 99%, 94%, and 99% for an iodine concentration of 21, 43, 64, 85, and 107 mg/dL, respectively. The poor visibility rate with 80–140 kVp and 107 mg/dL iodine concentration was due to the failure of iodine subtraction.

CONCLUSION. Dual-energy CT iodine-subtraction virtual unenhanced technique is capable of depicting urinary stones in iodine solutions of a diverse range of concentrations in a phantom study.

MATERIALS AND METHODS. We performed a retrospective study encompassing all acute trauma patients admitted to our institution over a 42-month period found to have renal parenchyma injuries on initial MDCT and also to have undergone a follow-up CT performed at least 1 month after trauma. We identified 54 patients who sustained blunt (n = 44) or penetrating (n = 10) abdominal trauma. The renal injuries were graded by two radiologists according to the Organ Injury Scaling Committee of the American Association for the Surgery of Trauma (AAST), grades I through V. Follow-up CT was reviewed for the presence of parenchymal distortion, scarring, or perfusion defects.

RESULTS. Of the 54 patients, 12 had grade I injury, eight had grade II injury, 22 had grade III injury, 10 had grade IV injury, and two had grade V injury. Grades I and II traumatic renal injuries were undetectable on follow-up CT. Grade III injuries resulted in the development of renal scars in 14 of 22 (64%) patients. Scarring resulted in all patients with grades IV and V injuries.

CONCLUSION. Grades I and II renal injuries heal completely, whereas higher grades of renal trauma result in permanent parenchymal scarring. Hence, incidentally discovered renal scars in patients with a history of minor renal trauma should be attributed tentatively to other causes that may or may not require additional investigation.

MATERIALS AND METHODS. Twenty-seven patients who had increased levels of prostate-specific antigen after high-intensity focused ultrasonic ablation underwent MRI and endorectal biopsy. The MR images and biopsy results were correlated for six prostate sectors. Residual or recurrent prostate cancer after treatment was defined as local tumor progression if the biopsy results showed cancer foci. Two readers blinded to the clinical findings and biopsy results used a 5-point scale to independently assess DCE-MR images and T2-weighted and diffusion-weighted MR images. The results were compared by use of the McNemar test with Bonferroni correction, generalized estimating equations, and receiver operating characteristic analysis.

RESULTS. After high-intensity focused ultrasonic ablation, local tumor progression was pathologically detected in 54 (33%) of 162 sectors in 18 patients. The sensitivities of DCE-MRI and T2-weighted MRI with DWI were 80% and 63% for reader 1 (p = 0.004) and 87% and 70% for reader 2 (p = 0.004). The specificities of DCE-MRI and T2-weighted MRI with DWI were 68% and 78% for reader 1 (p = 0.002) and 63% and 74% for reader 2 (p < 0.001). The accuracy rates of DCE-MRI and T2-weighted MRI with DWI were 72% and 73% for reader 1 (p > 0.05) and 71% and 73% for reader 2 (p > 0.05). The areas under the receiver operating characteristic curve for DCE-MRI and T2-weighted MRI with DWI were 0.77 and 0.77 for reader 1 and 0.85 and 0.81 for reader 2.

CONCLUSION. For prediction of local tumor progression of prostate cancer after high-intensity focused ultrasonic ablation, DCE-MRI was more sensitive than T2-weighted MRI with DWI, but T2-weighted MRI with DWI was more specific than DCE-MRI.

MATERIALS AND METHODS. A total of 51 patients who had undergone radical prostatectomy for prostatic adenocarcinoma 10 months to 6 years before underwent a combined endorectal coil MRI and dynamic gadolinium-enhanced MRI before endorectal sonographically guided biopsy of the prostatic fossa. The MRI combined with MR dynamic imaging results were correlated with the presence of recurrence defined as a positive biopsy result or reduction in prostate-specific antigen level after radiation therapy.

RESULTS. Overall data of 46 (25 recurred, 21 nonrecurred) out of 51 evaluated patients were analyzed. All recurrences showed signal enhancement after gadolinium administration and, in particular, 22 of 24 patients (91%) showed rapid and early signal enhancement. The overall sensitivity and specificity of MR dynamic imaging was higher compared with MRI alone (88%, [95% CI] 69–98% and 100%, 84–100% compared with 48%, 28–69% and 52%, 30–74%). MRI combined with dynamic imaging allowed better identification of recurrences compared with MRI alone (McNemar test: chi-square₁ = 16.67; p = < 0.0001).

CONCLUSION. MRI combined with dynamic contrast-enhanced MRI showed a higher sensitivity and specificity compared with MRI alone in detecting local recurrences after radical prostatectomy.

SUBJECTS AND METHODS. Eighty-five patients with 92 simple renal cysts were randomly assigned to two groups in a prospective controlled trial. One group was treated with sonographically guided continuous catheter drainage with negative pressure and the other group with single-session alcohol sclerotherapy. Patient demographics, clinical characteristics, treatment outcome, and complications were analyzed.

RESULTS. The initial volume of the cysts did not differ significantly between the groups, but the final volume was significantly smaller in the continuous drainage group (p = 0.026). During the 24-month follow-up period, 37 (40%) of the cysts disappeared completely: 24 (52%) of the 46 cysts in the drainage group and 13 (28%) of the 46 cysts in the sclerotherapy group (p = 0.033). In the sclerotherapy group, the probability of disappearance of the cysts was highly dependent on cyst size, being less for giant cysts (p = 0.01). Cyst size was not a significant factor in probability of disappearance in the drainage group (p = 0.15). The probability of disappearance of giant cysts (volume > 500 mL) differed significantly between the groups (p = 0.009), but there was no difference in probability of disappearance of moderately large cysts (p = 0.16). Three of 14 patients with giant cysts in the drainage group and 10 of 13 such patients in the sclerotherapy group had recurrences that necessitated additional treatment (p = 0.007). They were successfully treated with continuous catheter drainage.

CONCLUSION. Continuous catheter drainage with negative pressure is more efficient than single-session alcohol sclerotherapy in the management of giant cysts. For moderately large cysts, the two methods have similar results.

MATERIALS AND METHODS. We evaluated 45,007 initial short-interval follow-up mammograms from the Breast Cancer Surveillance Consortium interpreted 3–9 months after a probably benign assessment on a screening or diagnostic examination between 1994 and 2004. We linked these mammograms with patient characteristics and breast cancer diagnoses within 12 months. A subset of short-interval follow-up examinations (n = 13,907) was merged with radiologist characteristics collected from survey data from 130 interpreting radiologists. Using logistic regression, we fit generalized estimating equations to model sensitivity and specificity of short-interval follow-up mammograms by patient and radiologist characteristics.

RESULTS. For every 1,000 women, 8.0 women (0.8%) were diagnosed with breast cancer within 6 months and 11.3 (1.1%) within 12 months. Sensitivity was 83.3% (95% CI, 79.4–87.3%) for cancers diagnosed within 6 months and 60.5% (56.2–64.7%) for those diagnosed within 12 months. Specificity was 97.2% (96.9–97.6%) at 6 months and 97.3% (96.9–97.6%) at 12 months. Sensitivity at 12 months increased among women with unilateral short-interval follow-up mammograms (odds ratio, 1.56 [95% CI, 1.06–2.29]) and when the interpreting radiologist spent more than 10 hours a week in breast imaging (odds ratio, 3.25 [1.00–10.52]).

CONCLUSION. Initial short-interval follow-up mammography examinations had a lower sensitivity for detecting breast cancer within 12 months than other diagnostic mammograms (61% for short-interval follow-up vs 80% for diagnostic mammograms reported in the literature). However, sensitivity within the 6-month interval that is usually recommended for subsequent follow-up was 83%. Accuracy of short-interval follow-up mammograms was influenced by few patient and radiologist characteristics.

SUBJECTS AND METHODS. We prospectively classified 4,668 breast sonograms according to BI-RADS final assessment category. Suspicious sonographic findings were divided into major and minor suspicious findings. Category 1 was normal and category 2 was a benign finding such as cyst or nodule with uniform and intense hyperechogenicity. A nodule neither category 2 nor category 4 or 5 was defined as category 3. A nodule with one or more suspicious findings, not category 5, was defined as category 4. A nodule with two or more major suspicious findings was defined as category 5.

RESULTS. Of the 4,668 cases, 321 cases failed to undergo follow-up of at least 1 year. The PPV was 0.1% in category 1 (3/2,191), 0% in category 2 (0/773), 0.8% in category 3 (6/737), 31.1% in category 4 (161/519), and 96.9% in category 5 (123/127). In palpable lesions (n = 751), the PPV was 2.2% in category 1 (2/93), 0.9% in category 3 (2/217), 54% in category 4 (107/198), and 98% in category 5 (98/100). In nonpalpable lesions (n = 3,596), the PPV was 0.05% in category 1 (1/2,098), 0.8% in category 3 (4/520), 16.8% in category 4 (54/321), and 92.6% in category 5 (25/27).

CONCLUSION. As with mammography, placing sonographic lesions into BI-RADS categories is useful for predicting the presence of malignancy.

SUBJECTS AND METHODS. Between January 2002 and December 2004, 40 fetuses with isolated CDH and 450 control subjects were prospectively evaluated in two centers. Fetal lung volumes were estimated on 3D sonography using the rotational technique and fetal weight on 2D sonography using the Hadlock equation. The ratio of sonographic fetal lung volume to body weight was calculated in each case and was correlated with neonatal deaths using the Mann-Whitney U test. Accuracies of the ratio in predicting neonatal deaths and pathologic diagnosis of pulmonary hypoplasia were also evaluated.

RESULTS. The ratio of sonographic fetal lung volume to body weight is constant throughout gestation, with a mean value of 0.025. The ratio was significantly lower in neonates that died (median, 0.009; range, 0.004–0.021) than in those that survived (median, 0.011; range, 0.008–0.020) (p = 0.018). Pulmonary hypoplasia was suspected prenatally in 34 of 40 (85.0%) fetuses with CDH, in all cases of death (100%), and in seven of nine (77.8%) neonates that survived. At autopsy, pulmonary hypoplasia was diagnosed in 19 cases (86.4%). Accuracies of the ratio in predicting neonatal deaths and pulmonary hypoplasia were 64.5% (20/31) and 86.4% (19/22), respectively.

CONCLUSION. The sonographic fetal lung volume–body weight ratio can be used more accurately to diagnose pulmonary hypoplasia than to predict neonatal deaths in fetuses with isolated CDH. Further studies are necessary to show the prevalence of pulmonary hypoplasia in fetuses with isolated CDH and its importance for predicting neonatal deaths.

MATERIALS AND METHODS. Contrast-enhanced pelvic 1.5-T MRI was performed in 49 women before and after UAE over a 2-year period. Dominant (largest diameter) fibroids in intramural, submucosal, subserosal, pedunculated subserosal, and endocavitary locations were assessed on pre- (baseline) and postembolization MRI. Size, locations of dominant fibroids relative to endometrium and serosa before and after embolization were compared. The ratio between the largest endometrial interface and the maximum dimension of the dominant submucosal fibroid (interface–dimension ratio) was determined on baseline MRI. The infarction rate for dominant fibroids was estimated after UAE.

RESULTS. One hundred forty dominant fibroids were identified on baseline MRI. Forty-nine (35%) were intramural, 39 (28%) were submucosal, 34 (24%) were subserosal, eight (6%) were pedunculated subserosal, and 10 (6%) were endocavitary in location on preembolization MRI. After UAE, of 39 dominant submucosal fibroids, 13 (33%) became endocavitary: complete (n = 4), partial (n = 9) on the basis of European Society of Gynaecological Endoscopy (ESGE) classification. The preembolization mean interface–dimension ratio and mean diameters for dominant fibroids that became endocavitary were significantly greater than for those that did not become endocavitary after embolization (0.65 vs 0.32, p < 0.005; 8 vs 5.4 cm, p < 0.05, respectively). All dominant submucosal fibroids showed 100% infarction after UAE.

CONCLUSION. Submucosal fibroids with an interface–dimension ratio of greater than 0.55 are more likely to migrate into the endometrial cavity after UAE. The majority of these are expelled spontaneously without significant symptoms. Rarely, submucosal fibroids greater than 6 cm in size that become endocavitary may cause postprocedural complications requiring further intervention and medical treatment.

CONCLUSION. UAE can infarct fibroids. Fibroids spontaneously infarct after childbirth. Because the postpartum cervix is patulous, infarcted fibroids that fall into the uterine cavity easily exit the uterus. Each patient contemplating UAE should anticipate that infarcted fibroids bordering on or inside the uterine cavity may require cervical dilatation or hysteroscopic resection for removal. The addition of either of these two gynecology procedures should not necessarily be regarded as a UAE complication or treatment failure.

MATERIALS AND METHODS. Our pediatric cardiovascular 64-MDCT protocols use a weight-based algorithm to determine nominal tube voltage settings with 80, 100, and 120 kV. Automatic tube current modulation was used for each case. The mAs, volume CT dose index (CTDI_vol), and dose–length product (DLP) values were recorded and the effective dose calculated. On the basis of the selected nominal tube current, the dose values that would have been delivered without tube current modulation were also calculated. Scans were compared with 16-MDCT using 120 kVp and 120 mAs. Two radiologists independently rated image quality on a 5-point scale. Image noise was objectively measured within four different regions of interest. Findings at CT were clinically correlated with results of cardiac sonography, angiography, or surgery.

RESULTS. Thirty-eight 64-MDCT and 30 16-MDCT scans were evaluated. Mean diagnostic quality for 64-MDCT was rated at 3.6 ± 0.4 and mean image noise was 8.9 ± 4.5 H. Results with 16-MDCT were not significantly different: diagnostic quality (3.6 ± 0.4; p = 0.97) and image noise (9.1 ± 2.8 H; p = 0.31). Scanning with automatic tube current modulation significantly (p < 0.05) reduced the tube current time–product compared with scanning without automatic tube current modulation (–57.8% / 54.1 / 128 mAs) or with 16-MDCT (–47.9% / 54.1 / 104.37 mAs), respectively. The mAs values were significantly (p < 0.05) lower for 80 kVp than for 100 or 120 kVp scans, but image quality and image noise were not significantly (p = 0.24) different. Agreement between MDCT and clinical findings was excellent.

CONCLUSION. Under simulated conditions, automatic tube current modulation combined with low tube voltage settings significantly reduced radiation exposure and thus appears preferable in pediatric cardiovascular 64-MDCT.

MATERIALS AND METHODS. Ten steel stents of varying designs and sizes commonly used in the treatment of congenital heart disease were implanted in polyvinyl chloride (PVC) tubes and three of the 10 stents were partially obstructed with wax by filling 25% (mild) to 60% (moderate) of the lumen with contrast material. On a 64-MDCT scanner, the stents were scanned at tube voltages (kVp) of 80, 100, and 120 and at tube currents (mA) of 40, 80, 120, and 160. CT measurements of inner-stent diameter, strut thickness, and percent lumen (in-stent) stenoses were compared with biplane fluoroscopy of digital angiography.

RESULTS. The stent diameter and percent stenosis on all CT images were consistently smaller than measured on digital angiography but were highly correlated (r = 0.97; p < 0.0001) with improvement as stent diameter increased (93% agreement with digital angiography for 4-mm stent, up to 99% for 25-mm stent; p = 0.001). Moderate stenosis could be assessed better than mild stenosis (99% vs 91% agreement with digital angiography; p = 0.003). Increasing exposure settings improved CT correlation of all measurements for mA up to 120 and kVp up to 100 (98.1% agreement). Higher settings did not improve accuracy (93.9% for 160 mA at 120 kVp; p = 0.03).

CONCLUSION. CT is feasible to assess lumen narrowing of pediatric vascular stents at a wide range of tube settings. The study suggests that it is possible to lower the radiation exposure settings without loss in image quality or accuracy in detecting in-stent stenoses.

SUBJECTS AND METHODS. Two hundred eighteen patients with single or recurrent anterior shoulder dislocation underwent shoulder CT examination. Fifteen patients had bilateral dislocation. Prevalence and severity of glenoid bone loss and glenoid fracture were assessed. CT examinations of 56 control subjects without shoulder dislocation were evaluated for glenoid contour and side-to-side variation in glenoid width.

RESULTS. Glenoid bone loss was present in 27 (41%) of 66 patients with first-time unilateral dislocation and 118 (86%) of 137 patients with recurrent unilateral dislocation. Glenoid bone loss ranged from –0.3% to –33% (mean, –10.8% ± 7.9%). Seventy-four (51%) of 145 patients had ≤ 10% glenoid bone loss, 54 (37%) had between 10% and 20%, eight (6%) had between 20% and 25% glenoid bone loss, and nine (6%) had ≥ 25% glenoid bone loss. Glenoid rim fractures were present in 49 (21%) of 233 dislocated shoulders. The number of dislocations correlated moderately with the severity of glenoid bone loss (r = 0.56). The normal side-to-side glenoid width variation was small (0.46 ± 0.81 mm).

CONCLUSION. Glenoid bone loss is common in anterior shoulder dislocation. It is probably multifactorial in origin, is usually mild in degree, and has a maximum observed severity of –33%. Dislocation frequency cannot accurately predict the degree of bone loss.

MATERIALS AND METHODS. Monosegmental lumbar spondylodesis with autologous iliac crest graft or solvent-preserved bovine cancellous bone was performed on seven sheep. The fused spinal segments were explanted after 24 weeks and examined with clinical 64-MDCT, high-resolution peripheral quantitative CT, and contact radiography. In 2D views, the area of the disk space bridged by bone was assessed, and the grafts were examined for fractures.

RESULTS. In three of seven sheep, clinical CT erroneously showed stable consolidation, whereas contact radiography revealed a clearly visible graft fracture, as did high-resolution peripheral quantitative CT. There was a statistically significant difference (p = 0.038) between bone volume assessed with clinical CT and that assessed with contact radiography. There was an almost significant difference (p = 0.053) between volumes assessed with high-resolution peripheral quantitative CT and clinical MDCT.

CONCLUSION. High-resolution peripheral quantitative CT, a technique approved for clinical use, has higher resolution in imaging of bone structure than does 64-MDCT. Our results show that high-resolution peripheral quantitative CT is superior to 64-MDCT in assessing osseous implant integration after anterior spondylodesis. The specimen size limit, however, prohibits in vivo use of this method in evaluation of the human spine. Our results suggest that in clinical practice, persisting symptoms despite radiologic findings of consolidated spondylodesis may be related to graft failure, which cannot be detected with clinically available methods.

MATERIALS AND METHODS. At 1.5 T, 50 consecutive patients' hips were evaluated on sets of oblique axial images. Two musculoskeletal radiologists recorded their subjective opinion as to the alpha angle using a confidence scale of 1–5. Direct mathematic measurement of the alpha angle was done by a third independent observer and correlated with the subjective results. Correlations between the subjective and measured angles and interobserver variation were calculated.

RESULTS. Statistically, significant variability was seen in the subjective assessment of the alpha angle. When the alpha angle was > 55°, the area under the receiver operating characteristic curve (AUC) was 0.606, indicating that visual assessment is a poor predictor of a wide alpha angle. Even in patients with a measured normal alpha angle (< 55°), slightly fewer than half were subjectively thought to possibly, likely, or definitely have abnormal angles. Similarly, more than half of the abnormal cases (alpha angles > 55°) were subjectively thought to possibly or probably be normal.

CONCLUSION. Subjective assessment of alpha angles is suboptimal unless one is quite confident of a bone abnormality.

SUBJECTS AND METHODS. In this prospective study, neurosclerosis was performed on 82 patients by means of high-resolution sonographically guided injection of up to 0.8 mL of 80% phenol solution according to a standardized protocol.

RESULTS. During treatment all patients had marked improvement in terms of reduction of pain measured with a visual analog scale. Twelve (15%) of the subjects were pain free after one to three treatments, nine of the 12 achieving relief with the initial instillation. At 6-month follow-up evaluation, 52 patients assessed their present pain quantity with a simplified three-step score. Twenty (38%) of the 52 patients reported almost unnoticeable pain, and 33 (64%) reported pain equal to the minimum reached during therapy. In 18 (35%) of the 52 patients, the incidence of painful periods had markedly decreased. The neurosclerosis procedure had a low complication rate (5% rate of minor complications, 1.3% rate of major complications).

CONCLUSION. The high-resolution sonographically guided neurosclerosis procedure had a significantly better outcome than other documented treatments. Sonographically guided neurosclerosis should be included in the management of chronic phantom limb and stump pain.

SUBJECTS AND METHODS. Thirty-eight patients (23 men, 15 women) with clinically suspected rectal carcinoma underwent 3-T MRI. Coronal, axial, and sagittal T2-weighted sequences with and without fat suppression; axial T1-weighted spin-echo sequences; axial T1-weighted gradient-echo sequences with and without fat suppression; oblique 2D MR hydrography; and 3D fat-suppressed dynamic contrast-enhanced MRI were performed. Image quality with these sequences was evaluated by three radiologists experienced in body MRI. The significance of difference in results with the sequences was tested. The manner in which MRI staging and feasibility of sphincter-sparing surgery agreed with operative and pathologic findings was evaluated with kappa statistics.

RESULTS. Rectal carcinoma was identified on MRI and confirmed histologically in all 38 patients. MRI findings were correctly predictive of T category in 35 cases (accuracy, 92.1%). In 31 (96.9%) of 32 resectable cases,sphincter-sparing surgical approaches were accurately chosen on the basis of MRI findings. Among the 11 sequences, 3D fat-suppressed dynamic contrast-enhanced MRI best delineated tumor margins. Coronal and axial T2-weighted images also well depicted tumor margins with minimal artifact. T2-weighted images were superior to unenhanced T1-weighted images.

CONCLUSION. MRI of rectal cancer at 3 T is accurate for prediction of T category and the feasibility of sphincter-sparing surgery. The best images were obtained with coronal, sagittal, and axial T2-weighted sequences and 3D fat-suppressed dynamic contrast-enhanced MRI.

MATERIALS AND METHODS. The study included phantoms (23 phantom objects) and patients (16 polyps). Measurement with sliding calipers served as the reference for the phantom data. The mean of two independent colonoscopic measurements was the reference for the polyps. The automated measurement was developed for a computer-aided detection scheme, and the size of any detected object was obtained from measurement of its largest diameter. The automated measurement was compared with manual 2D and 3D measurements by two experienced observers.

RESULTS. For phantom data, the measurement variability of the automated method was significantly less than that of the two observers (p < 0.05), except for the 3D measurement by observer 1, as follows: automated, 0.86 mm; observer 1, 1.76 mm (2D), 0.96 (3D); observer 2, 1.34 mm (2D), 1.45 mm (3D). The variability of the automated method did not differ significantly from that of manual methods in measurement with patient data. The automated method had a systematic error for phantom data (1.9 mm).

CONCLUSION. For phantoms, the automated method has less measurement variability than manual 2D and 3D techniques. For true polyps, the measurement variability of the automated method is comparable with that of manual methods. The automated method does not suffer from intraobserver variability. Because systematic error can be calibrated, automated size measurement may contribute to a practical evaluation strategy.

CONCLUSION. Jejunal diverticula have characteristic findings on CT, appearing as discrete round or ovoid, contrast-, fluid-, or air-containing structures outside the expected lumen of the small bowel, with a smooth, barely discernible wall and no recognizable small-bowel folds. Not infrequently, these structures are seen to communicate directly with an adjoining small-bowel loop, a feature best recognized by scrolling the images. Our experience suggests that jejunal diverticulosis can often be recognized on the basis of the characteristic CT features of this condition.

CONCLUSION. Blue rubber bleb nevus, Proteus, Klippel-Trénaunay, and Kasabach-Merritt syndromes are a diverse group of vascular malformation and hemangiomatosis syndromes. Both cutaneous and visceral vascular lesions are associated with these disorders. Accurate diagnosis of these syndromes is important because they can be associated with serious complications, including life-threatening hemorrhage.

MATERIALS AND METHODS. We reviewed the medical records of 420 consecutive adult patients, 271 women and 149 men, 18 years old or older, referred from the emergency department to sonography examination for clinically suspected acute appendicitis between January 2003 and June 2006. Patients underwent sonography of the right upper abdomen and pelvis followed by graded compression and color Doppler sonography of the right lower quadrant. CT was performed in 132 patients due to inconclusive sonography findings or a discrepancy between the clinical diagnosis and the sonography diagnosis. Sonography and CT reports were compared with surgery or clinical follow-up as the reference standard. Statistical analyses were performed by Pearson's chi-square test and cross-tabulation software.

RESULTS. Sonography and CT correctly diagnosed acute appendicitis in 66 of 75 patients and in 38 of 39 patients, respectively, and correctly denied acute appendicitis in 312 of 326 and in 92 of 92 patients. Sonography was inconclusive in 17 of 418 cases and CT, in one of 132 cases. Sonography and CT allowed alternative diagnoses in 82 and 42 patients, respectively. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy for sonography were 74.2%, 97%, 88%, 93%, and 92%, respectively, and for CT, 100%, 98.9%, 97.4%, 100%, and 99%.

CONCLUSION. Sonography should be the first imaging technique in adult patients for the diagnosis of acute appendicitis and triage of acute abdominal pain. CT should be used as a complementary study for selected cases.

SUBJECTS AND METHODS. Two hundred fifteen consecutive outpatients were randomly assigned to receive either whole milk (n = 115) or VoLumen (n = 100). Results were independently reviewed by two radiologists who were blinded to the oral contrast agent used. Degree of bowel distention was qualitatively scored on a 4-point scale, and bowel wall visibility was graded qualitatively on a yes-or-no basis. A questionnaire regarding oral contrast tolerability was provided to each patient. Cost comparison of the two agents was performed.

RESULTS. No statistically significant differences were seen between whole milk and VoLumen with respect to degree of bowel distention and mural visualization for all segments of bowel studied (p > 0.05 for both reviewers). Significantly more patients ranked milk as pleasant in taste compared with VoLumen (p < 0.0001). More patients preferred milk compared with VoLumen (p < 0.0001). Milk was better tolerated than VoLumen, with fewer abdominal side effects, including abdominal discomfort (p = 0.019), cramping (p = 0.019), nausea (p = 0.016), and diarrhea (p = 0.0002). The cost per patient for VoLumen is $18 compared with $1.48 for milk.

CONCLUSION. Whole milk is comparable to VoLumen with respect to bowel distention and bowel wall visualization and has a lower cost, better patient acceptance, and fewer adverse symptoms. Milk is a cost-effective alternative to VoLumen as a low-attenuation oral contrast agent.

SUBJECTS AND METHODS. From April 1, 2007, to July 1, 2007, a total of 34 consecutively registered patients (19 men, 15 women; median age, 55 years) with various intraabdominal malignant tumors underwent preoperative CT and composed the study population. All patients underwent superparamagnetic iron oxide–enhanced MRI and portal phase contrast-enhanced 64-MDCT, including CT laparoscopy. CT laparoscopy is a form of volume-rendering 3D imaging of the liver that depicts the liver surface in detail.

RESULTS. Among 23 patients who underwent surgery for management of a primary tumor, four patients had seven superficial metastatic lesions of the liver surface. None of these lesions had been detected with preoperative axial CT or superparamagnetic iron oxide–enhanced MRI. In contrast, CT laparoscopy revealed four of seven lesions in four patients. On a lesion-by-lesion basis, the sensitivity was 57%, the positive predictive value was 100%, and the accuracy was 57%.

CONCLUSION. Our initial experience proves that CT laparoscopy is a promising method for detecting small superficial metastatic lesions of the liver surface. The findings can influence decisions regarding tumor resectability.

MATERIALS AND METHODS. We reviewed T2-weighted fast-recovery fast spin-echo images before and after gadolinium enhancement for 84 patients with 118 focal liver lesions. Solid lesions (22 hepatomas, seven ablated hepatomas, 12 metastatic lesions, six cases of focal nodular hyperplasia, five dysplastic nodules, one adenoma) were proved pathologically or with multiple follow-up studies. Nonsolid lesions were diagnosed as hemangiomas (n = 33) or cysts (n = 32) on the basis of imaging features. Two blinded radiologists interpreted the images independently, reading unenhanced images first and gadolinium-enhanced images at least 2 weeks later. Lesion conspicuity was ranked as follows: 1, poor; 2, moderate; 3, good; 4, excellent. The sign test was used for qualitative scoring of imaging pairs (unenhanced and gadolinium enhanced). The Fisher's exact test was used for subgroup analysis of solid and nonsolid lesions.

RESULTS. On gadolinium-enhanced T2-weighted images, 21 (17.8%) of 118 of the lesions had improved conspicuity, 86 (72.9%) had no difference in conspicuity, and 11 (9.3%) appeared worse. No statistically significant difference was found between unenhanced and enhanced images (p = 0.11), but a trend toward improved conspicuity with gadolinium enhancement was observed. Subgroup analysis showed that on gadolinium-enhanced T2weighted images, visualization of solid hepatic lesions (28.3%) was significantly better than that of nonsolid lesions (9.2%) (p = 0.01).

CONCLUSION. Compared with unenhanced T2-weighted images, gadolinium-enhanced T2-weighted images had a trend toward improved conspicuity of focal liver lesions. Subgroup analysis showed that visualization of solid lesions benefited significantly more from use of gadolinium-enhanced T2-weighted sequences than did visualization of nonsolid lesions.

MATERIALS AND METHODS. We retrospectively evaluated 248 patients who had been referred for planning sonography at our department between October 2005 and February 2006. We reviewed the radiologic reports of 256 planning sonography examinations in terms of the rate of feasible cases and the reasons for infeasibility. The reasons for infeasibility were classified in six categories: an inconspicuous tumor, an inadequate electrode path, an organ vulnerable to collateral thermal damage, a tumor that was too large or too many tumors, and a high risk of the heat sink effect. In addition, we assessed the treatment modality for the patients who were determined to have HCCs for which percutaneous radiofrequency ablation was not feasible.

RESULTS. In 141 (55%) of the 256 planning sonography examinations, percutaneous radiofrequency ablation was feasible. The remaining 115 (45%) planning sonography examinations revealed that radiofrequency ablation was not a feasible procedure. The reasons for infeasibility included an inconspicuous tumor in 77 patients (55.8%), an inadequate electrode path in 33 patients (23.9%), an organ vulnerable to collateral thermal damage in 14 patients (10.1%), a tumor that was too large or too many tumors in eight patients (5.8%), a high risk of the heat sink effect in five patients (3.6%), and a portal vein thrombosis in one patient (0.7%). One reason for infeasibility was found in 96 patients, two reasons in 19 patients, and four reasons in one patient. Seventy (61.9%) of 113 patients for whom radiofrequency ablation was not feasible underwent transcatheter arterial chemoembolization as an alternative treatment.

CONCLUSION. In approximately half of the patients for whom percutaneous radiofrequency ablation of HCC is requested, the procedure is not feasible, mainly due to inconspicuous tumors, at planning sonography. Additional objective criteria for assessing the feasibility of radiofrequency ablation and therapeutic strategies according to the reasons for infeasibility should be investigated further.

SUBJECTS AND METHODS. Nine healthy controls and 30 patients with biopsy-proven hepatitis C virus–related liver disease participated in this prospective study. Degree of fibrosis and histologic activity were scored according to the METAVIR classification. The percentage of involved hepatocytes was used to grade steatosis. Hepatic spectra were obtained with a 3-T spectroscopic system. Tenfold cross-validated stepwise discriminant analysis was performed to classify disease severity on the basis of the spectroscopic findings.

RESULTS. There was a strong correlation between ¹H-MR spectroscopically measured lipid concentration and the degree of steatosis at histologic examination (r = 0.9236, p < 0.0001). This finding enabled clear separation of groups according to degree of histologically determined steatosis. Variation in lipid concentration was consistent with the degree of steatosis (r = 0.7265, p < 0.0001) and stage of fibrosis (r = 0.8156, p < 0.0001). In univariate analysis, concentrations of both choline-containing compounds and glutamine–glutamate complex had a direct correlation with histologic grade (p < 0.0001) and degree of steatosis (p < 0.0001) but not with stage of fibrosis (p > 0.05). In multivariate analysis, the only factor independently associated with concentrations of choline-containing compounds and glutamine–glutamate complex was histologic grade. In cross-validated discriminant analysis based on choline-containing compound, glutamine–glutamate complex, and lipid resonance, 70% (21 of 30) of the histologic grade groups and 73% (22 of 30) of the steatosis groups were correctly classified.

CONCLUSION. Hydrogen-1 MR spectroscopy can be an alternative to liver biopsy in the evaluation of steatosis and necroinflammatory activity in liver disease but is not useful for complete evaluation of hepatic fibrosis.

SUBJECTS AND METHODS. From January 2000 to August 2005, 56 patients with HCC underwent TACE before orthotopic liver transplantation (OLT). Radiologic findings before and after TACE were assessed and correlated with histologic findings after OLT. The area of induced necrosis was pathologically evaluated in each HCC nodule.

RESULTS. One hundred thirty-one HCC nodules were detected at histologic study. One hundred seventeen HCC nodules (91.4%) were hyperenhancing in the arterial phase on the preoperative imaging studies. The percentage of tumor necrosis was greater than 90% in 48 nodules (38%), between 50% and 90% in 19 nodules (15%), and less than 50% in 61 nodules (48%); tumor necrosis data were not recorded for the remaining three nodules. The size of the preoperatively detected lesions ranged from 0.2 to 9 cm (mean, 2.58 cm). The mean percentage of tumor necrosis was 67.8% in this group, but it rose to 79.2% in the hypervascular lesions. The size of the nodules that were not detected preoperatively ranged from 0.1 to 1.9 cm (mean, 0.68 cm), and the mean percentage of tumor necrosis was only 1.57%.

CONCLUSION. TACE is a safe treatment in well-selected patients. Its antitumoral effect is high in hypervascular lesions (mean necrosis, 79.2%). It provides good local control in preoperatively diagnosed HCC (mean necrosis, 67.8%), but its impact is limited in lesions not detected preoperatively (mean necrosis, 1.57%).

MATERIALS AND METHODS. Of 984 patients assessed for eligibility, 514 patients with peripheral arterial disease were randomized to MR angiography (MRA) or duplex sonography in three hospitals and to MRA or CT angiography (CTA) in one hospital. The outcome measures included the clinical utility, functional patient outcomes, quality of life, and actual diagnostic and therapeutic costs related to the initial imaging test during 6 months of follow-up.

RESULTS. With adjustment for potentially predictive baseline variables, the learning curve, and hospital setting, a significantly higher confidence and less additional imaging were found for MRA and CTA compared with duplex sonography. No statistically significant differences were found in improvement in functional patient outcomes and quality of life among the groups. The total costs were significantly higher for MRA and duplex sonography than for CTA.

CONCLUSION. The results suggest that both CTA and MRA are clinically more useful than duplex sonography and that CTA leads to cost savings compared with both MRA and duplex sonography in the initial imaging evaluation of peripheral arterial disease.

SUBJECTS AND METHODS. Thirty-eight patients (25 men, 13 women; mean age ± SD, 55.0 ± 8.8 years) with suspected coronary artery disease underwent contrast-enhanced 64-MDCT (64 x 0.6 mm, 120 kV, 770 mAs_eff) and 1.5-T MRI (balanced fast-field echo; TR/TE, 3.3/1.6; flip angle, 60°; 50 phases). Double oblique short-axis MDCT and MR images were used for further analysis. End-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), and ejection fraction (EF) were computed from manually drawn endocardial contours of the right ventricle. For statistical analysis, repeated-measures analysis of variance and Pearson's correlation coefficients were calculated. Bland-Altman plots were computed.

RESULTS. In general, RV volumes calculated from 64-MDCT agreed well with those calculated from MRI. The mean EF (± SD) calculated from MDCT and MRI was 51.0% ± 7.8% and 51.4% ± 7.3%, respectively. An excellent correlation was observed for EDV (r = 0.99), ESV (r = 0.98), SV (r = 0.98), and EF (r = 0.97). Bland-Altman plots showed no systematic variation between MDCT and MRI data. No statistically significant differences (p ≤ 0.05) between the techniques were found.

CONCLUSION. Although contrast injection is optimized for visualization of the coronary arteries, retrospectively ECG-gated 64-MDCT permits reliable assessment of global RV function.

MATERIALS AND METHODS. We evaluated 35 bronchioloalveolar carcinomas and 17 atypical adenomatous hyperplasias that were histologically confirmed and that manifested pure GGO on thin-section helical CT scans. We recorded the age, sex, and smoking history (Brinkman index) of the patients. Two board-certified radiologists measured the maximum diameter and mean attenuation value of the nodules; the measured values were averaged for each nodule. Using a 3-point scale, they visually assessed the images for consensus with respect to nodular sphericity, marginal irregularity, vascular convergence, pleural retraction, and findings of an internal air bronchogram. CT findings of atypical adenomatous hyperplasia and bronchioloalveolar carcinoma were compared using univariate and multivariate logistic regression analysis; the odds ratio was computed using the atypical adenomatous hyperplasia group as the reference group.

RESULTS. By univariate analysis, the patient age, nodular maximum diameter, mean attenuation value, and findings of an internal air bronchogram were statistically significantly associated with bronchioloalveolar carcinoma (odds ratio [OR] = 1.10 [p = 0.012], OR = 1.27 [p < 0.01], OR = 1.01 [p = 0.023], and OR = 25.30 [p < 0.001], respectively), and sphericity was significantly associated with atypical adenomatous hyperplasia (OR = 0.059, p < 0.001). By multivariate analysis, sphericity was significantly associated with atypical adenomatous hyperplasia (OR = 0.125, p = 0.042) and findings of an internal air bronchogram were associated with bronchioloalveolar carcinoma (OR = 16.10, p = 0.007).

CONCLUSION. Nodular sphericity and an internal air bronchogram were useful at thin-section helical CT performed to differentiate between bronchioloalveolar carcinoma and atypical adenomatous hyperplasia. Interobserver agreement was high for each finding.

SUBJECTS AND METHODS. Seventy-nine patients with memory impairment and 16 volunteer controls participated in the study. MRI was performed with a 1.5-T system. Conventional MR images and diffusion tensor images were obtained for all participants. The diffusion tensor imaging data were postprocessed, and low b-value, fractional anisotropy, and fractional anisotropy color-coded maps were calculated. With the three maps as an anatomic reference, fractional anisotropy was measured for hippocampal formations, superior longitudinal fascicles, posterior cingulate gyri, and the splenium of the corpus callosum. Kruskal-Wallis and Steel-type multiple-comparison nonparametric tests were performed for the statistical analysis.

RESULTS. The fractional anisotropy values for the splenium of the corpus callosum, bilateral posterior cingulate gyri, and bilateral superior longitudinal fascicles of patients with mild cognitive impairment and those with probable Alzheimer's disease were significantly lower than the values of controls. No differences were found in hippocampal formations in any group. No significant difference was found in fractional anisotropy values in comparisons of mild cognitive impairment versus possible Alzheimer's disease and probable Alzheimer's disease or comparisons of probable Alzheimer's disease and possible Alzheimer's disease.

CONCLUSION. Diffusion tensor imaging is a promising technique for the evaluation of patients with probable mild cognitive impairment. Early detection of the disease expands the treatment options, increasing the likelihood of a good clinical response and enhancing the quality of life of patients and their relatives. Further studies with larger populations are needed to confirm the role of diffusion tensor imaging in the evaluation of memory impairment.

SUBJECTS AND METHODS. For the control study, three healthy volunteers underwent laryngeal phonation CT while vocalizing the vowels /hee/, /ih/, and /ah/, and reconstructed coronal images of the larynx were obtained. After the control study, 28 patients with unilateral vocal cord paralysis underwent laryngeal phonation CT during /hee/ phonation, which was chosen as a most appropriate vowel for this purpose. Changes in the paralyzed and normal vocal cords were evaluated quantitatively and qualitatively on coronal reconstruction images.

RESULTS. On the coronal reconstructed images from the healthy volunteers, the normal cords had a shoulder formation appearance, and the cords lay within 1 mm lateral to the midline during phonation. For patients with vocal cord paralysis during /hee/ phonation, the average angle formed by the long axis of the vocal cord and the midline was 71.67° on the affected side and 92.21° on the normal side (p = 0.001). The vocal cord edges lay 1.5 mm lateral to the midline on the affected side and 0.44 mm lateral to the midline on the normal side (p = 0.003). In the qualitative study, the two observers found the coronal reconstructions of the laryngeal phonation CT scans yielded a higher detection rate than did conventional axial CT.

CONCLUSION. Laryngeal phonation CT proved more useful for evaluating vocal cord paralysis than did conventional CT and can be used as a primary diagnostic tool when vocal cord paralysis is suspected.

MATERIALS AND METHODS. Minimally invasive postmortem CT angiography was performed on 10 human cadavers via access to the femoral blood vessels. Separate perfusion of the arterial and venous systems was established with a modified heart–lung machine using a mixture of an oily contrast medium and paraffin (five cases) and a mixture of a water-soluble contrast medium with polyethylene glycol (PEG) 200 in the other five cases. Imaging was executed with an MDCT scanner.

RESULTS. The minimally invasive femoral approach to the vascular system provided a good depiction of lesions of the complete vascular system down to the level of the small supplying vessels. Because of the enhancement of well-vascularized tissues, angiography with the PEG-mixed contrast medium allowed the detection of tissue lesions and the depiction of vascular abnormalities such as pulmonary embolisms or ruptures of the vessel wall.

CONCLUSION. The angiographic method with a water-soluble contrast medium and PEG as a contrast-agent dissolver showed a clearly superior quality due to the lack of extravasation through the gastrointestinal vascular bed and the enhancement of soft tissues (cerebral cortex, myocardium, and parenchymal abdominal organs). The diagnostic possibilities of these findings in cases of antemortem ischemia of these tissues are not yet fully understood.

MATERIALS AND METHODS. Studies were performed on three wine bottles containing cocaine solutions that were confiscated at the Swiss border. Reference values were obtained by scans of different sorts of commercially available wine and aqueous solutions of dissolved sugar. All bottles were scanned using MDCT, and data evaluation was performed by measuring the mean peak of Hounsfield units. To verify the method, simulated testing was performed.

RESULTS. Using measurements of the mean peak of Hounsfield units enables the detection of dissolved cocaine in wine bottles in a noninvasive and rapid fashion. Increasing opacity corresponds well with the concentration of dissolved cocaine. Simulated testing showed that it is possible to distinguish between cocaine-contaminated and uncontaminated wine bottles.

CONCLUSION. The described method is an efficacious screening method to detect cocaine-contaminated bottles that are hidden between untreated bottles in cargo. The noninvasive examination of cargo allows a questionable delivery to be tracked without arousing the suspicion of the smugglers.

CONCLUSION. This article illustrates these basic Fourier principles and their relationship to MRI.

MATERIALS AND METHODS. In this HIPAA-compliant retrospective study, 741 FDG PET/CT scans obtained during the winter months (October 1–April 30) for patients who prepared with a high-fat, very-low-carbohydrate, protein-permitted protocol were compared with 1,229 FDG PET scans obtained during the winter months for patients who prepared by fasting. FDG uptake on PET scans co-localized with regions of fat identified on the CT scans was assumed to represent hypermetabolic BAT. The categoric variables frequency of occurrence of hypermetabolic BAT (present or not) and the sex ratios of the groups before and after the change in preparation were compared by use of a chi-square test. The continuous variables of age and blood glucose level were compared by use of a two-tailed Student's t test.

RESULTS. In this intention-to-treat analysis, there was no difference between the fasting (n = 1,229) and the high-fat, very-low-carbohydrate, protein-permitted diet (n = 741) groups in terms of age and sex. Patients who prepared with the high-fat diet had a significantly lower frequency of hypermetabolic BAT uptake on FDG PET scans during the winter months (p<0.0002) and had lower blood glucose levels (p<<0.001).

CONCLUSION. In this intention-to-treat analysis, use of a high-fat preparation protocol significantly lowered the frequency of uptake of FDG by hypermetabolic BAT on FDG PET studies. Use of this protocol has the potential to decrease the rate of false-positive findings on oncologic FDG PET scans.