Detection of pulmonary nodules with scoutless fixed-dose ultra-low-dose CT: a prospective study.

OBJECTIVES: To determine the accuracy of scoutless, fixed-dose ultra-low-dose (ULD) CT compared to standard-dose (SD) CT for pulmonary nodule detection and semi-automated nodule measurement, across different patient sizes. METHODS: Sixty-three patients underwent ULD and SD CT. Two readers examined all studies visually and with computer-aided detection (CAD). Nodules detected on SD CT were included in the reference standard by consensus and stratified into 4 categories (nodule category, NODCAT) from the Dutch-Belgian Lung Cancer Screening trial (NELSON). Effects of NODCAT and patient size on nodule detection were determined. For each nodule, volume and diameter were compared between both scans. RESULTS: The reference standard comprised 173 nodules. For both readers, detection rates on ULD versus SD CT were not significantly different for NODCAT 3 and 4 nodules > 50 mm3 (reader 1: 93% versus 89% (p = 0.257); reader 2: 96% versus 98% (p = 0.317)). For NODCAT 1 and 2 nodules < 50 mm3, detection rates on ULD versus SD CT dropped significantly (reader 1: 66% versus 80% (p = 0.023); reader 2: 77% versus 87% (p = 0.039)). Body mass index and chest circumference did not influence nodule detectability (p = 0.229 and p = 0.362, respectively). Calculated volumes and diameters were smaller on ULD CT (p < 0.0001), without altering NODCAT (84% agreement). CONCLUSIONS: Scoutless ULD CT reliably detects solid lung nodules with a clinically relevant volume (> 50 mm3) in lung cancer screening, irrespective of patient size. Since detection rates were lower compared to SD CT for nodules < 50 mm3, its use for lung metastasis detection should be considered on a case-by-case basis. KEY POINTS: • Detection rates of pulmonary nodules > 50 mm3are not significantly different between scoutless ULD and SD CT (i.e. volumes clinically relevant in lung cancer screening based on the NELSON trial), but were different for the detection of nodules < 50 mm3(i.e. volumes still potentially relevant in lung metastasis screening). • Calculated nodule volumes were on average 0.03 mL or 9% smaller on ULD CT, which is below the 20-25% interscan variability previously reported with software-based volumetry. • Even though a scoutless, fixed-dose ULD CT protocol was used (CTDIvol0.15 mGy), pulmonary nodule detection was not influenced by patient size.

Is systematic long-term sonographic follow-up after arthroscopic rotator cuff repair useful in asymptomatic patients?

OBJECTIVE: To establish whether ultrasonographic (US) appearance is correlated to functional outcome in asymptomatic patients 12 months after rotator cuff repair. MATERIAL AND METHODS: 26 asymptomatic patients at twelve months after arthroscopic cuff repair and 26 controls were retrospectively included. A clinical score (Constant's Shoulder Score, CSS) was compared with a US score (the modified Sugaya Score, mSS). The minimal thickness of the anterior and posterior parts of the cuff was also measured. RESULTS: CSS improved significantly from preoperatively to postoperatively (mean increased from 41 to 82.6, p<.001). Correlation between the postoperative CSS and the minimal thickness of the cuff at its anterior and posterior part (p=0.55 and p=0.13) was not significant. There was also no significant correlation between the postoperative CSS and mSS (p=0.34). CONCLUSION: The sonographic appearance of the cuff repair is not correlated to the functional outcome at 12 months after arthroscopic surgery in asymptomatic patients.

Redescending Stomach: A Rare and Potentially Lethal Complication of Gastric Herniation.

Large gastric hernias are common and usually cause minor symptoms. Rarely, complete intrathoracic herniation of the stomach is complicated by strangulation. The underlying mechanism can be gastric volvulus or the less recognized phenomenon of gastric fundus redescent. We describe a case where this rare but potentially lethal complication of gastric herniation is present. Additionally, we show that gastric pneumatosis, a sign associated with ischemia, can be initially visualized on a plain chest radiograph in this setting. Teaching point: Redescent of the fundus is a possible, but unrecognized cause of gastric strangulation in intrathoracic stomachs.

Large Chondrosarcoma of the Lower Rib Presenting as a Cystic Abdominal Mass.

Teaching point: Chondrosarcoma of the lower rib may present with only minimal calcified chondroid matrix and may be misinterpreted as a liver lesion.

Postmortem high-resolution fetal magnetic resonance imaging in three cases of lower urinary tract obstruction.

In this manuscript we report 3 cases of severe lower urinary tract obstruction diagnosed before 20 weeks of pregnancy. All cases had a very similar prenatal presentation with a megacystis, bilateral hydro-ureteronephrosis and increased echogenicity of the kidneys. High-resolution postmortem magnetic resonance imaging (MRI), following termination of pregnancy, enabled accurate investigation of the underlying cause of the urinary tract obstruction, by depicting the presence of an urethral valve, urethral atresia and cloacal dysgenesis. Postmortem fetal MRI provides high anatomical detail and is very suitable to investigate congenital anomalies of the lower urinary tract. In case (timely or consented) conventional autopsy is not possible, MRI is an excellent alternative.

A Retropubic Cartilaginous Cyst in a Context of Surgery for Prostate Cancer.

Teaching Point: Retropubic cartilaginous cysts are rare, benign lesions originating from the symphysis pubis that should be considered in the differential diagnosis of a small slow-growing retropubic nodule.

Anterior sacral meningocoele presenting as acute urinary retention. A case report.

Anterior sacral meningocoele is caused by a congenital hiatus in the anterior sacrum. We report a very rare case which presented as acute urinary retention. The common findings of anterior sacral meningocele include atypical low back pain, urological and gynaecological symptoms. Acute urinary retention as a presenting symptom does not appear to have been mentioned in the English literature.

Musculoskeletal injuries in a resource-constrained environment: comparing diagnostic accuracy of on-the-spot ultrasonography and conventional radiography for bone fracture screening during the Paris-Dakar rally raid.

BACKGROUND: Ultrasound (US) is a good first-line alternative for the diagnosis of bone fractures in adults as well as children. Our study shows that, compared to X-ray, in a resource-constrained environment, on-site US has a high sensitivity (98%) and specificity (96%) in the diagnosis of bone fractures. PURPOSE: To compare the accuracy of on-the-spot US with conventional radiography in the screening for bone fractures during the Paris-Dakar rally raid. MATERIAL AND METHODS: Eighty-three patients (81 men, 2 women) with clinically suspected bone fractures were included in 2013 and 2014. They underwent X-ray and US on the spot, blindly interpreted by two musculoskeletal radiologists. Using X-ray as gold standard, we calculated sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for US, for each anatomic location. The accuracy of US and radiography were also assessed, as were the number of fragments and their degree of displacement (Student's t-test). RESULTS: Compared with X-ray, sensitivity, specificity, PPV, and NPV of on-site US were, respectively, for the presence (or absence) of fractures: 98%, 98%, 100%, and 95%. The accuracy of US was 99%. Only one radial styloid process fracture was misdiagnosed with US. There was no significant difference between US and X-ray (P > 0.93) concerning the number of fragments and their degree of displacement. CONCLUSION: Bedside musculoskeletal ultrasound performed by trained musculoskeletal radiologists is a useful method in determining and assessing bone fractures in a resource constrained environment.

Caroli disease: review of eight cases with emphasis on magnetic resonance imaging features.

BACKGROUND: Caroli disease is a rare congenital disorder characterized by segmental, nonobstructive dilatation of intrahepatic bile ducts. The term Caroli syndrome is used for the association of Caroli disease with congenital hepatic fibrosis. STUDY AIMS: To provide an overview of the clinical presentation and imaging features of Caroli disease and syndrome, with an emphasis on magnetic resonance imaging. PATIENTS AND METHODS: Retrospective analysis of medical records on eight patients in whom a histologic diagnosis of Caroli disease or syndrome had been made. RESULTS: Presenting signs and symptoms were (hepato)splenomegaly, hematemesis and/or melena, cholangitis, jaundice, and recurrent fever. The central dot sign, defined in the literature as a dot or bundle of strong contrast enhancement within dilated intrahepatic ducts, was found in seven cases on various imaging modalities. A 'dot-like structure' was found in one case in which only unenhanced studies were available. There was a tendency toward a right hepatic-lobe predominance. CONCLUSION: There is an overlap between the imaging features of Caroli disease and Caroli syndrome. Our findings support earlier reports that the central dot sign is highly specific for the disease, and that it can be reliably detected by current imaging techniques.