Diagnostic per-lesion performance of a simulated gadoxetate disodium-enhanced abbreviated MRI protocol for hepatocellular carcinoma screening.

AIM: To evaluate the diagnostic per-lesion performance of a simulated gadoxetate disodium-enhanced abbreviated MRI (AMRI) in cirrhotic and chronic hepatitis B (CHB) patients for hepatocellular carcinoma (HCC) screening. MATERIALS AND METHODS: Seventy-nine consecutive patients at risk for HCC due to cirrhosis and/or CHB were included in this retrospective study. For each patient, the first gadoxetate disodium-enhanced MRI between 2008 through 2014 was analysed. Two independent readers read an anonymised abbreviated image set comprising axial T1-weighted (W) images with fat saturation in the hepatobiliary phase, 20 minutes or more after gadoxetate injection, and axial T2W single-shot fast spin echo images. Each observation >10 mm was scored as negative or suspicious for HCC. Inter-reader agreement was assessed. A composite reference standard was used to determine the per-lesion diagnostic performance for each reader. RESULTS: Inter-reader agreement was substantial (κ = 0.75). The final reference standard showed 27 HCCs in 13 patients (median 21 mm, range 11-100 mm). The two readers each correctly scored 23 as suspicious for HCC (sensitivity = 85.2%), scored a total of 27 and 32 observations as suspicious for HCC (positive predictive value [PPV] = 85.2% and 71.9%), and scored 83 and 78 observations or complete examinations as negative for HCC (negative predictive value [NPV] = 95.2% and 94.9%). CONCLUSIONS: The AMRI protocol provides higher per-lesion sensitivity and NPV than reported values for ultrasound, the current recommended technique for screening, and similar per-lesion sensitivity and PPV to reported values for complete dynamic contrast-enhanced MRI.

Meta-analysis of genome-wide linkage studies of systemic lupus erythematosus.

A genetic contribution to the development of systemic lupus erythematosus (SLE) is well established. Several genome-wide linkage scans have identified a number of putative susceptibility loci for SLE, some of which have been replicated in independent samples. This study aimed to identify the regions showing the most consistent evidence for linkage by applying the genome scan meta-analysis (GSMA) method. The study identified two genome-wide suggestive regions on 6p21.1-q15 and 20p11-q13.13 (P-value=0.0056 and P-value=0.0044, respectively) and a region with P-value<0.01 on 16p13-q12.2. The region on chromosome 6 contains the human leukocyte antigen cluster, and the chromosome 16 and 20 regions have been replicated in several cohorts. The potential importance of the identified genomic regions are also highlighted. These results, in conjunction with data emerging from dense single nucleotide polymorphism typing of specific regions or future genome-wide association studies will help guide efforts to identify the actual predisposing genetic variation contributing to this complex genetic disease.

Acetabular stress fractures in military endurance athletes and recruits: incidence and MRI and scintigraphic findings.

OBJECTIVE: To evaluate the incidence and the MRI and scintigraphic appearance of acetabular stress (fatigue) fractures in military endurance athletes and recruits. DESIGN AND PATIENTS: One hundred and seventy-eight active duty military endurance trainees with a history of activity-related hip pain were evaluated by both MRI and bone scan over a 2-year period. Patients in the study ranged in age from 17 to 45 years. They had hip pain related to activity and had plain radiographs of the hip and pelvis that were interpreted as normal or equivocal. The study was originally designed to evaluate the MRI and scintigraphic appearance of femoral neck stress fractures. Patients had scintigraphy and a limited MRI examination (coronal imaging only) within 48 h of the bone scan. Twelve patients demonstrated imaging findings compatible with acetabular stress fractures. RESULTS: Stress fractures are common in endurance athletes and in military populations; however, stress fracture of the acetabulum is uncommon. Twelve of 178 patients (6.7%) in our study had imaging findings consistent with acetabular stress fractures. Two patterns were identified. Seven of the 12 (58%) patients had acetabular roof stress fractures. In this group, two cases of bilateral acetabular roof stress fractures were identified, one with a synchronous tensile sided femoral neck stress fracture. The remaining five of 12 (42%) patients had anterior column stress fractures, rarely occurring in isolation, and almost always occurring with inferior pubic ramus stress fracture (4 of 5, or 80%). One case of bilateral anterior column stress fractures was identified without additional sites of injury. CONCLUSIONS: Stress fractures are commonplace in military populations, especially endurance trainees. Acetabular stress fractures are rare and therefore unrecognized, but do occur and may be a cause for activity-related hip pain in a small percentage of military endurance athletes and recruits.

Multicentric reticulohistiocytosis: case report with immunohistochemical analysis and literature review.

This report describes the case of a patient with multicentric reticulohistiocytosis. Immunohistochemical analysis revealed prominent markers of monocyte/macrophage origin, as well as the presence of tumor necrosis factor alpha, interleukin-1beta (IL-1beta), and IL-12; the occurrence of the latter in this disease has not previously been reported. Clinical, laboratory, radiographic, and histologic findings in multicentric reticulohistiocytosis are reviewed. In addition, all published cases of multicentric reticulohistiocytosis which included reports of cytokine and immunohistochemical analysis are reviewed, and evidence for a monocyte/macrophage origin and role in disease pathogenesis is provided.

History and physical examination to estimate the risk of ectopic pregnancy: validation of a clinical prediction model.

STUDY OBJECTIVE: To prospectively validate a clinical prediction model for ectopic pregnancy (EP). METHODS: Prospective cohort with 14-month derivation and 12-month validation phases. All hemodynamically stable, first-trimester patients with abdominal pain or vaginal bleeding who presented to a military teaching hospital emergency department underwent follow-up until an outcome of intrauterine pregnancy (IUP) or EP was established. Patients were separated into the high-risk group, defined as having either peritoneal signs or definite cervical motion tenderness; intermediate-risk group, defined as the presence of pain or tenderness, other than midline cramping, plus absence of fetal heart tones, and absence of tissue visible at the cervical os; and low-risk group (neither high- nor intermediate-risk) using recursive partitioning. RESULTS: Summarizing both phases, 915 patients had 845 (93%) IUPs and 70 (7.6%) EPs, with 18 (1.9%) lost to follow-up. The clinical prediction model classified 75 (8.2%) into the high-risk group (sensitivity 31%, 95% confidence interval [CI] 21% to 44%; specificity 94%, 95% CI 92% to 95%); and 644 (70%) in the intermediate-risk group (sensitivity 98%, 95% CI 89% to 100%; specificity 25%, 95% CI 22% to 29%). The remaining 196 (21%) patients who met neither high-risk nor intermediate-risk criteria were classified into the low-risk group. On the basis of EP prevalence of 7.7%, the risk of EP was less than 1% (95% CI 0% to 3%) for the low-risk group, 7% (95% CI 5% to 10%) for the intermediate-risk group, and 29% (95% CI 19% to 41%) for the high-risk group. CONCLUSION: This clinical prediction model is useful for estimating the risk of EP in first-trimester patients, particularly when ancillary testing is equivocal or not readily available.

Derivation of a clinical prediction model for the emergency department diagnosis of ectopic pregnancy.

OBJECTIVE: To derive a clinical prediction model for estimating the pretest probability of ectopic pregnancy in ED patients with first-trimester abdominal pain or vaginal bleeding. METHODS: All hemodynamically stable first-trimester patients presenting to the ED of a tertiary care military teaching hospital over a 14-month period with a chief complaint of abdominal pain and/or vaginal bleeding had clinical data coded prior to determining outcome. They were then followed longitudinally until a criterion standard pregnancy outcome was established. RESULTS: Of the 486 patients enrolled, 280 (58%) had viable intrauterine pregnancies, 167 (34%) had nonviable intrauterine pregnancies, and 39 (8%) had ectopic pregnancies. Using a recursive partitioning model, a high-risk group was derived (that was separated from intermediate and low-risk groups), consisting of patients with abdominal peritoneal signs or definite cervical motion tenderness, with a sensitivity of 31% (95% CI: 17-48%), a specificity of 93% (95% CI: 90-95%), a positive likelihood ratio of 4.3, and a negative likelihood ratio of 0.74. A low-risk group, consisting of patients with either fetal heart tones or tissue at the cervical os, or the absence of pain other than midline menstrual-like cramping and lacking any pelvic tenderness, was differentiated from an intermediate-risk group, with a sensitivity of 96% (95% CI: 81-100%), a specificity of 22% (95% CI: 18-26%), a positive likelihood ratio of 1.2, and a negative likelihood ratio of 0.17. CONCLUSION: A clinical prediction model for estimating the probability of ectopic pregnancy in ED patients has been derived. It may prove to have practical clinical application for estimating pretest probability of ectopic pregnancy as well as assisting in medical decision making when laboratory and ultrasonographic findings are nondiagnostic. Clinical application should await prospective validation in an independent sample.

Resolution of abnormal MR signal intensity in patients with stress fractures of the femoral neck.

OBJECTIVE: The purpose of this study was to describe the natural evolution of abnormal MR signal intensity after the diagnosis of a stress fracture of the femoral neck and to ascertain the time to resolution of that abnormal signal intensity. SUBJECTS AND METHODS: Ten patients who had been previously diagnosed with stress fractures of the femoral neck after positive MR scans of the hip were examined with MR imaging at regular intervals. In each patient T1-weighted and short inversion time inversion recovery (STIR) sequences were obtained until the abnormally bright, diffuse MR signal intensity (representing edema) disappeared from the STIR images. Time to resolution was correlated with each patient's age and presence or absence of a fatigue line on MR imaging. Statistical analysis was done using Fisher's exact test. RESULTS: Edema resolved in seven patients within 3 months of initial diagnosis, in two patients within 6 months, and in the remaining patient within 12 months. We found no statistically significant correlation between time to resolution and patient age or the presence of a fatigue line on MR imaging. Residual sclerosis occurred in five patients, all of whom had a fatigue line. Two of these patients developed bright T1 signal (fatty marrow conversion) around the area of sclerosis. In the remaining three patients, STIR images revealed a brightened fatigue line, which we presumed was caused by granulation tissue. CONCLUSION: In this study, 90% of patients showed resolution of abnormal MR signal intensity on STIR imaging within 6 months of the initial diagnosis of stress fracture of the femoral neck. Such data may prove helpful in examining patients with recurrent symptoms who undergo repeated MR scanning. When an abnormally bright, diffuse MR signal intensity on STIR imaging is seen more than 6 months after an original injury, such abnormal signal intensity is likely to represent new injury.

Multiresolution detection of coherent radar targets.

We develop and investigate several novel multiresolution algorithms for detecting coherent radar targets embedded in clutter. These multiresolution detectors exploit the fact that prominent target scatterers interfere in a characteristic manner as resolution is changed, while multiresolution clutter signatures are random. We show, both on simulated and collected synthetic aperture radar data, that these multiresolution algorithms yield significant detection improvements over single-pixel, single-resolution constant false alarm rate (CFAR) methods that use only the finest available resolution.

The incidence of deep venous thrombosis in anterior cruciate ligament reconstruction.

We prospectively studied the incidence of deep venous thrombosis (DVT) in anterior cruciate ligament reconstruction. A total of 67 male patients (aged 19 to 39 years) were examined by compression ultrasonography to determine the presence of DVT in the operated extremity. All patients were studied preoperatively and 2 to 3 days postoperatively. The area of examination was from popliteal vein to inguinal ligament; no DVT prophylaxis was used. No patient had clotting preoperatively. The incidence of DVT was 1 in 67. One patient had an asymptomatic noncompressible lesion in the proximal femoral vein on postoperative day 3; repeat examination at day 10 was normal. Unless other risk factors are present, we do not recommend routine prophylaxis for male patients younger than 40 years of age who are undergoing anterior cruciate ligament reconstruction.

The superiority of magnetic resonance imaging in differentiating the cause of hip pain in endurance athletes.

The accuracy of magnetic resonance imaging of the hip was prospectively evaluated in 19 military subjects engaged in endurance training. These patients had hip pain, negative radiographs, and radionuclide bone scans consistent with femoral neck stress fracture. Twenty-two hips were identified as positive for femoral neck stress fracture by bone scan. Each patient underwent magnetic resonance imaging and 6-week follow-up plain radiographs of the hips. Magnetic resonance imaging studies differentiated femoral neck stress fractures from a synovial pit, iliopsoas muscle tear, iliopsoas tendinitis, obturator externus tendinitis, avascular necrosis of the femoral head, and a unicameral bone cyst. The follow-up radiographs were used to verify the diagnosis of stress fracture. The radiographs showed healing callus in patients with stress fractures. Patients with diagnoses other than stress fractures had no changes on follow-up radiographs. Magnetic resonance imaging studies were as sensitive and much more specific than bone scan in determining the cause of hip pain. Radionuclide bone scan had an accuracy of 68% for femoral neck stress fractures with 32% false-positive results; MRI was 100% accurate. Magnetic resonance imaging proved to be superior to radionuclide bone scanning in providing an early and accurate diagnostic tool that aided in the differential diagnosis of hip pain in the young endurance athlete.

Fibrous pseudotumor of the tunica vaginalis testis: imaging appearance.

Fibrous pseudotumor is a benign paratesticular tumor that typically presents as a painless mass of the hemiscrotum. Because this tumor can mimic a malignant process, it is usually not diagnosed preoperatively. We describe a case of fibrous pseudotumor of the tunica vaginalis, demonstrating the ultrasound and magnetic resonance image (MRI) appearance with pathologic correlation.

Color Doppler sonographic findings in patients with transitional cell carcinoma of the bladder and renal pelvis.

The purposes of this study were (1) to evaluate the color Doppler sonographic findings in patients with transitional cell carcinoma of the bladder and renal pelvis, (2) to determine if color Doppler sonography could predict tumor grade and stage, and (3) to determine whether tumor vascularity is related to size. A total of 15 patients with 16 bladder transitional cell carcinomas and one patient with renal pelvic transitional cell carcinoma were evaluated prospectively with transabdominal color Doppler ultrasonography. The presence or absence of visible vascularity and the resistive index were correlated with tumor size, cytologic grade, and tumor stage. Statistical analysis was performed with Fisher's exact test. Seven (41%) of 17 tumors had visible vascularity: five (45%) of 11 high-grade transitional cell carcinomas were vascular, whereas two (33%) of six low-grade transitional cell carcinomas were vascular (P = 1.00). Three of five (60%) of the invasive lesions were vascular, but the vascularity was not predictive of tumor stage (P = 0.593). The vascular high-grade tumors tended to have more numerous and larger visible vessels than the vascular low-grade lesions. No tumor smaller then 23 mm was vascular, but the size of the tumor was not predictive of the vascularity (P = 0.1172). The resistive index was measurable in six tumors, but it was not predictive of grade or stage. Color Doppler ultrasonography is not helpful clinically in the evaluation of transitional cell carcinoma as tumor grade, stage, and size are not related to vascularity.(ABSTRACT TRUNCATED AT 250 WORDS)

Schistosomiasis involving the breast.

A case of ectopic granulomatous schistosomiasis involving the breast is reported. Although schistosomiasis can involve almost any organ, involvement of the breast is very rare; to the authors' knowledge, there have been only three previously reported cases of breast involvement in the literature. This case was discovered at routine screening mammography. Innumerable, segmentally distributed, fine calcifications and mild architectural distortion were seen at mammography, and a biopsy was performed to exclude malignancy. There appears to be no way to accurately discriminate this disease from breast cancer before biopsy.