Twiddler's Syndrome.

Teaching point: Twiddler's syndrome is a very rare but potentially disastrous complication after implantation of a neurostimulator or pacemaker, caused by twisting of the generator within the subcutaneous pocket, resulting in dislodgement and/or interruption of the electrodes that should be reported on x-ray.

Diagnostic accuracy of a fast MRI T2-sequence for the diagnosis of internal herniation after Roux-and-Y gastric bypass during pregnancy: A retrospective single center study.

PURPOSE: The objective of this retrospective study was to evaluate the diagnostic accuracy of a fast sequence Magnetic Resonance Imaging (MRI) sequence, T2- half-Fourier acquisition single-shot turbo spin echo (HASTE) for the diagnosis of internal herniation (IH) in pregnant patients with a history of Roux-en-Y gastric bypass (RYGB). METHODS: Abdominal MRI studies, performed for the clinical suspicion of IH of pregnant patients with a history of RYGB, were analyzed by two abdominal radiologists. Thirty-one cases were included and for each case both readers independently evaluated the T2 HASTE sequence in different planes (axial, coronal and sagittal) to determine the presence or absence of IH. Diagnostic performance of T2 HASTE MRI was evaluated by calculating sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy compared to the clinical diagnosis of IH as the gold standard. IH was diagnosed as the presence of herniated bowel through the mesenteric defect at the time of surgical exploration. IH was deemed absent if the surgical exploration showed no herniated bowel or if patients had no subsequent clinical symptoms of IH after 90 days of clinical follow-up. RESULTS: The results in this study, with 16 patients with IH and 15 patients without IH, portray a high accuracy for the detection of IH, ranging from 87.9% to 90.3%. This fast T2 sequence shows a high NPV (86.7% - 100.0% 87.7), sensitivity (88.9% - 100.0%) and specificity (80.0% - 86.7%). This study also portrayed a substantial interobserver agreement (0.741) for the evaluation of IH. CONCLUSION: T2 HASTE MRI shows an excellent sensitivity and NPV for the detection of IH in pregnant patients. The fast acquisition time makes this sequence useful in the emergency setting, and it can be used for the diagnosis or exclusion of IH in pregnant patients.

Prevalence, progression and implications of breast artery calcification in patients with chronic kidney disease.

Breast arterial calcification (BAC) is increasingly recognized as a specific marker of medial calcification. The present retrospective observational cohort study aimed to define the prevalence, progression rate, risk factors and clinical implications of BAC in chronic kidney disease (CKD) patients across stages of disease. The presence and extent of BAC were determined on mammograms in 310 females (58.7 ± 10.8 years, Caucasian) with CKD across various stages of disease [CKD G2-5D n = 132; transplant (Tx) recipients n = 178]. In a subset of 88 patients, repeat mammography was performed, allowing us to calculate the annualized BAC rate. Overall, BAC was observed in 34.7% of the patients. BAC prevalence (P = 0.02) and BAC score (P = 0.05) increased along the progression of CKD. In the overall cohort, patients with BAC were characterized by older age, more cardiovascular disease, more inflammation, higher pulse pressure and borderline higher prevalence of diabetes and were more often treated with a vitamin K antagonist (VKA). The BAC progression rate was significantly lower in Tx patients as compared with CKD G5D. Progressors were characterized by more inflammation, worse kidney function, higher BAC score and higher serum phosphate level (Tx only) at baseline and were more often treated with a VKA. Major adverse cardiovascular event-free survival was significantly worse in Tx patients with BAC. In conclusion, BAC is common among CKD patients, progresses at a slower pace in Tx patients as compared with CKD 5D and associates with dismal cardiovascular outcomes. BAC score, kidney function, serum phosphate at baseline and VKA usage seem to be important determinants of progression.

Cervical Spondylodiscitis in an Infant with Torticollis.

Teaching point: Narrowing of the intervertebral space and destruction of the adjacent vertebral end plates on conventional radiography or CT should raise suspicion for spondylodiscitis in symptomatic infants.

Chest CT Diagnosis of COVID-19: Accuracy using CO-RADS and CT-Involvement Scoring.

OBJECTIVES: Both Reporting and Data System (CO-RADS) and CT-involvement scores (CTIS) have been proposed for evaluation of COVID-19 on chest CT. The purpose of this single-center, retrospective study was to evaluate both scoring systems to diagnose COVID-19 infection in a high-prevalence area. MATERIALS AND METHODS: Chest CT datasets (n = 200) and available reverse transcription polymerase chain reaction (RT-PCR) on nasopharyngeal swab were included. CT scans were assigned to four 'imaging groups' after scoring for both CO-RADS and CTIS. Diagnostic accuracy of chest CT was calculated respectively using RT-PCR and clinical diagnosis as gold standards: False-negatives and false-positives of chest CT regarding RT-PCR were studied in more depth using the medical files. RESULTS: The 'imaging group' including CO-RADS 4/5 scores reached the highest diagnostic values for COVID-19 considering either the initial RT-PCR or the final clinical diagnosis as the standard of reference: accuracies of 172/200 (86%) to 181/200 (90.5%), sensitivities of 60/80 (88.2%) to 70/79 (88.6%), specificities of 112/132 (84.9%) to 111/121 (91.7%), negative predictive values (NPV) of 112/120 (93.3%) to 111/120 (92.5%), respectively. False-negative CTs regarding RT-PCR were mainly explained by imaging very early in the disease course (5 out of 8 cases) or COVID-19 infection with no/minor respiratory symptoms (3 out of 8 cases). CONCLUSION: Assessing chest CT using CO-RADS is a valuable diagnostic approach for COVID-19 infection in a high-prevalence area, with a higher accuracy than CTIS.

Subacute combined degeneration of the cervical and dorsal spinal cord in a 40-year-old male patient: A case report.

Subacute combined degeneration of the spinal cord is a neurologic complication of vitamin B12 deficiency. It presents as a potentially reversible demyelination of the posterior and lateral columns of the cervical and dorsal spinal cord. We present the case of a 40-year-old male with progressive sensory and motor deficit from the lower extremities ascending to the mid-thoracic region. A combination of laboratory tests and magnetic resonance imaging confirmed the diagnosis of subacute degeneration of the spinal cord due to vitamin B12 deficiency.

Bilateral lesions of the basal ganglia and thalami (central grey matter)-pictorial review.

The basal ganglia and thalami are paired deep grey matter structures with extensive metabolic activity that renders them susceptible to injury by various diseases. Most pathological processes lead to bilateral lesions, which may be symmetric or asymmetric, frequently showing characteristic patterns on imaging studies. In this comprehensive pictorial review, the most common and/or typical genetic, acquired metabolic/toxic, infectious, inflammatory, vascular and neoplastic pathologies affecting the central grey matter are subdivided according to the preferential location of the lesions: in the basal ganglia, in the thalami or both. The characteristic imaging findings are described with emphasis on the differential diagnosis and clinical context.