Cardiorespiratory arrest after iso-osmolar iodinated contrast injection: A case report of contrast-induced encephalopathy following contrast-enhanced computed-tomography.

RATIONALE: Contrast-induced encephalopathy (CIE) is a rare complication caused by administration of intravascular contrast media and characterized by acute reversible neurological disturbance. Most of the CIE cases are reported after arterial administration of contrast media such as during cerebral or coronary angiographies, yet only a few articles have reported CIE secondary to intravenous contrast. A case of CIE secondary to intravenous contrast administration is reported here. PATIENT CONCERNS: A 68-year-old man was admitted to our hospital for contrast-enhanced chest computed-tomography (CT) examination due to suspected pulmonary nodules. After CT examination, the patient lost consciousness and experienced a cardiorespiratory arrest. An emergency plain brain CT was done immediately which showed abnormal cortical contrast enhancement and cerebral sulci hyperdensity. DIAGNOSES: After excluding other differential diagnoses such as electrolytes imbalance, hypo/hyperglycemia, cardiogenic pathologies and other neurological emergencies such as cerebral hemorrhage, cerebral infarction, the final diagnosis of CIE was made. INTERVENTIONS: The patient was admitted to the intensive care unit for further management. A series of supportive treatments were arranged. OUTCOMES: Follow-up visits at the outpatient clinic showed no lasting neurological deficits. LESSONS: CIE should be considered as 1 of the differential diagnoses for a patient with acute neurologic symptoms after iodinate contrast administration. Neuroradiological imaging examinations are essential to rule out other etiologies such as acute cerebral infarction or intracranial hemorrhage.

Rib fracture detection system based on deep learning.

Rib fracture detection is time-consuming and demanding work for radiologists. This study aimed to introduce a novel rib fracture detection system based on deep learning which can help radiologists to diagnose rib fractures in chest computer tomography (CT) images conveniently and accurately. A total of 1707 patients were included in this study from a single center. We developed a novel rib fracture detection system on chest CT using a three-step algorithm. According to the examination time, 1507, 100 and 100 patients were allocated to the training set, the validation set and the testing set, respectively. Free Response ROC analysis was performed to evaluate the sensitivity and false positivity of the deep learning algorithm. Precision, recall, F1-score, negative predictive value (NPV) and detection and diagnosis were selected as evaluation metrics to compare the diagnostic efficiency of this system with radiologists. The radiologist-only study was used as a benchmark and the radiologist-model collaboration study was evaluated to assess the model's clinical applicability. A total of 50,170,399 blocks (fracture blocks, 91,574; normal blocks, 50,078,825) were labelled for training. The F1-score of the Rib Fracture Detection System was 0.890 and the precision, recall and NPV values were 0.869, 0.913 and 0.969, respectively. By interacting with this detection system, the F1-score of the junior and the experienced radiologists had improved from 0.796 to 0.925 and 0.889 to 0.970, respectively; the recall scores had increased from 0.693 to 0.920 and 0.853 to 0.972, respectively. On average, the diagnosis time of radiologist assisted with this detection system was reduced by 65.3 s. The constructed Rib Fracture Detection System has a comparable performance with the experienced radiologist and is readily available to automatically detect rib fracture in the clinical setting with high efficacy, which could reduce diagnosis time and radiologists' workload in the clinical practice.

Quantitative and semi-quantitative CT assessments of lung lesion burden in COVID-19 pneumonia.

This study aimed to clarify and provide clinical evidence for which computed tomography (CT) assessment method can more appropriately reflect lung lesion burden of the COVID-19 pneumonia. A total of 244 COVID-19 patients were recruited from three local hospitals. All the patients were assigned to mild, common and severe types. Semi-quantitative assessment methods, e.g., lobar-, segmental-based CT scores and opacity-weighted score, and quantitative assessment method, i.e., lesion volume quantification, were applied to quantify the lung lesions. All four assessment methods had high inter-rater agreements. At the group level, the lesion load in severe type patients was consistently observed to be significantly higher than that in common type in the applications of four assessment methods (all the p < 0.001). In discriminating severe from common patients at the individual level, results for lobe-based, segment-based and opacity-weighted assessments had high true positives while the quantitative lesion volume had high true negatives. In conclusion, both semi-quantitative and quantitative methods have excellent repeatability in measuring inflammatory lesions, and can well distinguish between common type and severe type patients. Lobe-based CT score is fast, readily clinically available, and has a high sensitivity in identifying severe type patients. It is suggested to be a prioritized method for assessing the burden of lung lesions in COVID-19 patients.

Primary alveolar rhabdomyosarcoma of retrorectal-presacral space in an adult patient: A case report of an uncommon tumor with rare presentation.

RATIONALE: Rhabdomyosarcoma (RMS) has known as a highly malignant soft tissue sarcoma, representing 5% to 10% of all solid tumors in childhood. Alveolar rhabdomyosarcoma (ARMS) of the retrorectal-presacral space is an extremely rare lesion for adult, no study has been reported in the English literature. PATIENT CONCERNS: A 51-year-old male presented with abdominal pain for 1 month, significantly worse when having a bowel movement. DIAGNOSIS: Computed tomography (CT) and magnetic resonance imaging (MRI) of the pelvis showed a solid-cystic, enhancing lesion of dimension located in retrorectal-presacral space. The surgical specimen was reported as ARMS after pathological evaluation. INTERVENTIONS: The tumor was complete surgical resection, and after surgery, the patient was treated with combination chemotherapy. OUTCOMES: At 23 months follow up, the patient was asymptomatic with no evidence of metastases or local recurrence. LESSONS: Improvements in imaging in addition to early surgical intervention and chemotherapy treatment are crucial to improve survival chances against RMS.