Rare magnetic resonance imaging findings of intracranial solitary fibrous tumor: A case report.

RATIONALE: Solitary fibrous tumor (SFT) is a rare mesenchymal spindle cell tumor. SFT in the central nervous system (CNS) is rare. This case reports rare magnetic resonance imaging (MRI) findings of intracranial SFT (ISFT). PATIENT CONCERNS: We report a 47-year-old female patient who was found to have weakness in her right limb with walking instability 2 months before the visit. DIAGNOSES: Based on imaging, the provisional diagnosis was meningioma. Postsurgical histopathological diagnosis confirmed World Health Organization (WHO) grade I SFT/hemangiopericytoma (HPC). INTERVENTIONS: The lesion was totally excised. The patient improved remarkably after the operation, without any signs of associated limb movement disorder. OUTCOMES: No local recurrence or metastases were observed in the follow-up 3 months after the surgery. LESSONS: Intracranial SFT is a rare mesenchymal tumor. Due to different tumor components, imaging manifestations are diverse and lack of characteristics, so preoperative diagnosis is challenging. Our case provides a rare ISFT with significantly decreased signal intensity in T2 weighted images (T2WI), which is an important supplement to the rare imaging findings of intracranial SFT.

Diagnostic performance of radiomics using machine learning algorithms to predict MGMT promoter methylation status in glioma patients: a meta-analysis.

PURPOSE: We aimed to assess the diagnostic performance of radiomics using machine learning algorithms to predict the methylation status of the O6-methylguanine-DNA methyltransferase (MGMT) promoter in glioma patients. METHODS: A comprehensive literature search of PubMed, EMBASE, and Web of Science until 27 July 2021 was performed to identify eligible studies. Stata SE 15.0 and Meta-Disc 1.4 were used for data analysis. RESULTS: A total of fifteen studies with 1663 patients were included: five studies with training and validation cohorts and ten with only training cohorts. The pooled sensitivity and specificity of machine learning for predicting MGMT promoter methylation in gliomas were 85% (95% CI 79%-90%) and 84% (95% CI 78%-88%) in the training cohort (n=15) and 84% (95% CI 70%-92%) and 78% (95% CI 63%-88%) in the validation cohort (n=5). The AUC was 0.91 (95% CI 0.88-0.93) in the training cohort and 0.88 (95% CI 0.85-0.91) in the validation cohort. The meta-regression demonstrated that magnetic resonance imaging sequences were related to heterogeneity. The sensitivity analysis showed that heterogeneity was reduced by excluding one study with the lowest diagnostic performance. CONCLUSION: This meta-analysis demonstrated that machine learning is a promising, reliable and repeatable candidate method for predicting MGMT promoter methylation status in glioma and showed a higher performance than non-machine learning methods.

Evaluation of isolated abdominal visceral artery dissection with multi-scale spiral computed tomography: a retrospective case series.

BACKGROUND: To evaluate the role of multi-slice spiral computed tomography (MSCT) angiography in the diagnosis of spontaneous isolated visceral artery dissection (SIVAD). METHODS: Twenty-seven patients with abdominal SIVAD were included in the study. The MSCT scans of the patients were subjected to various post-processing techniques to visualize the visceral artery wall. Clinical features including arterial dissection, thrombosis, dissection length, true/false lumen, and complications were recorded. RESULTS: Type I, IIa, and IIb SIVADs were observed in 11, 6, and 10 patients, respectively. Superior mesenteric artery (SMA) dissection was the most common (n = 16), followed by abdominal aortic dissection (n = 6), splenic artery dissection (n = 2), renal artery dissection (n = 2), and splenic artery dissection (n = 1). One patient with SMA dissection suffered small intestine ischemia, 1 with splenic artery dissection had splenic infarction, and 1 patient with left renal artery dissection experienced renal infarction. The false lumen was bigger than the true lumen in 20 patients, with 9 patients having thrombus. The true lumen was bigger than the false lumen in 7 patients. CONCLUSIONS: MSCT angiography is a valuable technique in the diagnosis and treatment of patients with SIVAD. Patients with abdominal pain suspected due to SIVAD should be examined with MSCT angiography for early detection of SIVAD.

Dysembryoplastic neuroepithelial tumour in the cerebellum: case report and literature review.

BACKGROUND: Dysembryoplastic neuroepithelial tumours (DNETs) are benign brain tumours that most commonly arise at supratentorial sites. The cerebellum is an extremely rare location for DNETs. We report a case of cerebellar DNET along with literature review. CASE DESCRIPTION: A girl aged 2 years and 3 months presented with gait instability. Imaging examination showed a very large cystic-solid mass with mixed densities/signal intensities in the cerebellum. The entire lesion was successfully removed, and the patient achieved a good prognosis. CONCLUSION: Cerebellar DNET lacks characteristic imaging-based signs, and the diagnosis mainly relies on pathological examination. However, this diagnosis should be considered when a cerebellar lesion in child consists of cystic-solid mass with mixed densities/signal intensities.

Endometrial stromal sarcoma extending to the pulmonary artery: A rare case report.

BACKGROUND: Endometrial stromal sarcoma (ESS) is a rare malignant mesenchymal tumor. Early in the disease, the findings on magnetic resonance imaging are similar to those of leiomyoma. When the lesion involves both vascular and cardiac tissue, it might be misdiagnosed as intravenous leiomyomatosis, which is not common in the clinic. CASE SUMMARY: We present the case of a 34-year-old female patient with tumor embolus, which extended from the right iliac vein and ovarian vein to the inferior vena cava (IVC), and then to the right atrium and right ventricle, and finally protruded into the pulmonary artery. The patient had undergone a hystero-myomectomy 7 years previously. Based on the findings of the imaging examinations, the diagnosis of intravenous leiomyomatosis was considered preoperatively. The patient then underwent complete resection of the endovascular and intracardiac tumor embolus. The postoperative pathology results confirmed metastatic ESS with endovascular and intracardiac involvement. The patient was discharged from hospital in good condition, and there was no sign of recurrence 5 mo after the operation. CONCLUSION: Extending from the iliac vein and ovarian vein to the IVC, this metastatic ESS invaded both vascular and cardiac tissues. For patients with ESS involving vascular and cardiac tissues, pathological examinations are essential for the differential diagnosis, such as intravenous leiomyomatosis. In addition, due to the high recurrence rate of ESS, long-term and close follow-up evaluation is necessary.

Occipital nodular fasciitis easily misdiagnosed as neoplastic lesions: A rare case report.

BACKGROUND: Nodular fasciitis (NF) is a benign disease originating from fascial tissue and most commonly occurs in the extremities, followed by the trunk, head, and neck. NF of the head and neck occurs mainly in the face and neck, and it has not been reported in the occipital region. CASE SUMMARY: A 30-year-old man was admitted because of a mass in the left occipital region. Imaging examination revealed a soft tissue nodule in the left occipital area. An enhanced magnetic resonance imaging scan showed characteristic inverted target and fascial tail signs. Histopathological analysis showed a large amount of spindle cell proliferation, and immunohistochemistry showed positive expression of SMA in the spindle cells in the lesion. Finally, nodular fasciitis was diagnosed. CONCLUSION: NF of the head and neck is rare, but the possibility of NF should be considered when nodules or masses with rapid subcutaneous growth are found and tenderness in the head and neck is present. Imaging examination, in combination with clinical manifestations and histopathological examination, can improve the diagnostic accuracy for the disease. After diagnosis, local surgical resection is the first choice of treatment.

Neuroimaging findings of cerebral syphilitic gumma.

Cerebral syphilitic gumma is a rarely reported disease of the central nervous system. Magnetic resonance imaging (MRI) is an important diagnostic method for syphilitic gumma. The present study aimed to describe and characterize neuroimaging results from 6 patients with pathologically diagnosed cerebral syphilitic gumma. The 6 patients (age, 32-61 years) underwent brain CT and MRI, with 1 patient also undergoing whole-body 2-deoxy-2-(fluorine-18)fluoro-D-glucose-positron emission tomography/CT (18F-FDG PET/CT). Non-enhanced CT, conventional T1 weighted imaging (T1WI) and T2WI, diffusion weighted imaging (DWI) and gadolinium-enhanced T1WI images were acquired for all patients. The CT and MRI scans were retrospectively reviewed by two experienced radiologists for consensus on the location, number, size, T1WI, T2WI and DWI signal intensity characteristics, extent of vasogenic oedema, and enhancement patterns. In total, the 6 patients exhibited 10 lesions, nine of which were located in the cerebral hemisphere, primarily in the grey matter. The remaining lesion was located in the fourth ventricle, leading to mild-to-moderate hydrocephalus. The diameters of the identified 10 lesions ranged from 0.9-6.5 cm, with a mean diameter of 3.9 cm. The main feature observed in CT was low density and in MRI the features were T1WI and DWI hypointensity and T2WI hyperintensity. A single case exhibited syphilis gumma with massive haemorrhage. Ring-like or strip-like signs (n=5), accompanied by the dural tail sign (n=2) and homogeneous enhancement (n=1), were noted on T1WI with gadolinium. The 18F-FDG PET/CT performed in one patient of a cerebral syphilis gumma revealed low uptake and metabolism. The present study indicated that gadolinium-enhanced MRI combined with 18F-FDG PET/CT and laboratory examinations are helpful in distinguishing cerebral syphilitic gumma from brain tumors and infectious diseases, therefore avoiding unnecessary surgery.

Diffusion-weighted magnetic resonance imaging for the detection of metastatic lymph nodes in patients with lung cancer: A meta-analysis.

The aim of the present meta-analysis was to evaluate the diagnostic value of diffusion-weighted imaging (DWI) in differentiating metastatic from non-metastatic lymph nodes in patients with lung cancer. A systematic literature search was performed to identify eligible original studies. The quality of included studies was assessed using 'quality assessment of diagnostic accuracy studies' (QUADAS-2). Meta-analysis was performed to pool sensitivity and specificity, to calculate the positive likelihood ratio (PLR), the negative likelihood ratio (NLR) and the diagnostic odds ratio (DOR), and to construct the summary receiver operating characteristic (SROC) curve. The homogeneity, threshold effect and publication bias were also investigated. Meta-regression analysis was performed to identify the sources of heterogeneity. A total of 10 studies with 11 datasets met the inclusion criteria, which comprised 796 patients with a total of 2,433 lymph nodes. The pooled diagnostic sensitivity was 0.78 [95% confidence interval (CI): 0.74-0.81] and the pooled diagnostic specificity was 0.88 (95% CI: 0.86-0.89). The PLR, NLR, and DOR were 7.11 (95% CI: 4.39-11.52), 0.24 (95% CI: 0.18-0.33), and 31.14 (95% CI: 17.32-55.98), respectively. The area under the SROC curve was 0.90. No publication bias was found (bias=-0.15, P=0.887). Notable heterogeneity was, however, observed, and patient selection, type of lung cancer, number of enrolled lymph nodes, reference standard, B-value and the type of scanner were the sources of heterogeneity (P<0.05). No significant threshold effect was identified (P=0.537). In conclusion, DWI has been revealed to be a valuable magnetic resonance imaging (MRI) modality, with good diagnostic performance for distinguishing metastatic from non-metastatic lymph nodes in patients with lung cancer. Therefore, DWI may be a useful supplement to conventional MRI techniques.