18F-Fluciclovine Uptake in an Incidentally Discovered Meningioma in a Patient With a History of Metastatic Prostate Cancer: A Case Report.

Meningiomas are common, benign tumors found in the dural layers of the central nervous system (CNS) that are often found incidentally. 18F-fluciclovine is an amino acid radiotracer that is used to monitor the recurrence of prostate cancer due to its high uptake in prostate cancer cells. This case report outlines a patient with a retinoblastoma tumor suppressor gene (RB1) mutation and prostate cancer metastasis to the bone incidentally noted to have an enhancing, extra-axial mass on a screening MRI. On prior scans, the mass displayed increased 18F-fluciclovine uptake. Because prostate cancer can metastasize to the meninges, especially in older patients with advanced disease, consideration was given to the progression of his oncological disease. However, additional imaging validated the existence and size of the mass, making a meningioma the final diagnosis. Meningeal metastases can be virtually indistinguishable from other CNS tumors, including meningiomas appearing as single or multiple dural-based, enhancing masses, and without prior imaging, further investigation is warranted.

The vanishing nasal septum sign: a case of severe fungal sinusitis.

Acute invasive fungal sinusitis (AIFS) is a fungal infection of the nasal cavity and paranasal sinuses with associated invasion of adjacent vessels and soft/hard tissues. It usually occurs in immunocompromised patients and may follow a rapid course of less than four weeks with high mortality rate. We report a 39-year-old male with relapse of acute myelogenous leukemia (AML) who was under evaluation for neutropenic fever. On his sinus CT, there was loss of calcification of his nasal septum when compared to a prior head CT, a sign indicative of an aggressive infectious process. He was diagnosed with AIFS and underwent emergent surgical debridement and systemic antifungal therapy, leading to a positive outcome. The sign described on CT ("Vanishing Nasal Septum" sign) may provide an additional, reliable tool to prospectively identify locally aggressive cases of invasive fungal infections of the nasal cavity at an earlier stage and improve patient outcomes.

Intradural extramedullary pleomorphic xanthoastrocytoma: A case report.

BACKGROUND: Pleomorphic xanthoastrocytomas (PXAs) are uncommon intradural and typically intramedullary astrocytic central nervous system tumors. Although they commonly occur supratentorially, they are rarely seen in the spine. CASE DESCRIPTION: A 43-year-old male presented with cervical neck pain and right-sided radicular symptoms. He was found to have an intradural extramedullary mass at the C5-C6 level. The lesion was fully excised and proved to be a PXA. Of interest, the lesion did not recur on postoperative MR imaging studies obtained 7 months later. CONCLUSION: While rare, primary intradural extramedullary spinal PXA has been reported. Here, we review such a lesion occurring in a 43-year-old male who did well following gross total excision of the tumor.

Aggressive spinal haemangiomas: imaging correlates to clinical presentation with analysis of treatment algorithm and clinical outcomes.

OBJECTIVE: Aggressive spinal haemangiomas (those with significant osseous expansion/extraosseous extension) represent approximately 1% of spinal haemangiomas and are usually symptomatic. In this study, we correlate imaging findings with presenting symptomatology, review treatment strategies and their outcomes and propose a treatment algorithm. METHODS: 16 patients with aggressive haemangiomas were retrospectively identified from 1995 to 2013. Imaging was assessed for size, location, CT/MR characteristics, osseous expansion and extraosseous extension. Presenting symptoms, management and outcomes were reviewed. RESULTS: Median patient age was 52 years. Median size was 4.5 cm. Lumbar spine was the commonest location (n = 8), followed by thoracic spine (n = 7) and sacrum (n = 2); one case involved the lumbosacral junction. 12 haemangiomas had osseous expansion; 13 had extraosseous extension [epidural (n = 11), pre-vertebral/paravertebral (n = 10) and foraminal (n = 6)]. On CT, 11 had accentuated trabeculae and 5 showed lysis. On MRI, eight were T1 hyperintense, six were T1 hypointense and all were T2 hyperintense. 11 symptomatic patients underwent treatment: chemical ablation (n = 6), angioembolization (n = 3, 2 had subsequent surgery), radiotherapy (n = 2, 1 primary and 1 adjuvant) and surgery (n = 4). Median follow-up was 20 months. Four of six patients managed only by percutaneous methods had symptom resolution. Three of four patients requiring surgery had symptom resolution. CONCLUSION: Aggressive haemangiomas cause significant morbidity. Treatment is multidisciplinary, with surgery reserved for large lesions and those with focal neurological signs. Minimally invasive procedures may be successful in smaller lesions. ADVANCES IN KNOWLEDGE: Aggressive haemangiomas are rare, but knowledge of their imaging features and treatment strategies enhances the radiologist's role in their management.

Limitations of dual time point PET in the assessment of lung nodules with low FDG avidity.

FDG PET has long shown efficacy in the evaluation of indeterminate pulmonary nodules. More recently, the use of dual time point imaging has been looked at as a means for improving sensitivity and accuracy. While initial reports were very promising, more recent results looking specifically at pulmonary lesions with low levels of FDG avidity demonstrated limitations. These lesions (initial maximum standard uptake value of less than 2.5) are of particular interest due to the fact that well-differentiated adenocarcinomas, broncheoaveolar carcinoma and carcinoid may have low FDG avidity on standard PET imaging, leading to false-negative exams. Our study retrospectively reviewed the accuracy of dual time point (DTP) FDG PET imaging to determine if it aided in the identification of malignant pulmonary nodules when initial time point imaging showed a maximum SUV of less than 2.5. 113 patients had undergone a total of 130 DTP PET/CT with 152 lesions assessed. 67 lesions were subsequently definitively diagnosed as benign or malignant based upon biopsy or imaging follow-up. Utilizing a maximum SUV increase of 10%, which optimizes our sensitivity and specificity; our results demonstrate a sensitivity of 63% and a specificity of 59%, similar to other investigators evaluating lesions with low FDG avidity. Increasing or decreasing this threshold did not improve our results, nor did the addition of lesions with maximum SUV's of 2.5 or greater on initial imaging. Specifically in nodules with low FDG avidity (max SUV<2.5), the sensitivity was 61%, specificity 58%, and accuracy was 60%. Our findings suggest that DTP FDG PET may not be of benefit in the assessment of pulmonary nodules with maximum SUV of less than 2.5 on initial imaging.

Cutaneous infections with community-acquired MRSA in aviators.

Methicillin-resistant Staphylococcus aureus (MRSA) is a pathogen of growing concern among community-based practices in medicine, particularly those in the military. The risk of colonization and infection by community-acquired MRSA (CA-MRSA) is significantly higher among military members than that of the general population. The unique environment of the deployed, military aviator (impaired hygiene practices, close contact in warm, space-limited cockpits, and shared life support equipment) may increase risks of colonization, infection, and transmission of CA-MRSA and hence warrants the clinical attention of the flight surgeon. Studies of molecular genetics indicate that isolates of CA-MRSA contain a unique mobile genetic element (SCCmec type IV), indicating that CA-MRSA evolved separately from nosocomially acquired MRSA. Skin infections involving CA-MRSA are unlike their nosocomial counterparts in that CA-MRSA infections are susceptible to multiple classes of antibiotics and, on average, are clinically more aggressive. Awareness of this pathogen and appropriate clinical intervention can lead to prompt resolution of the infection and reduce rates of CA-MRSA colonization.

Cellulitis in Grade III ankle sprain requiring treatment for antibiotic-resistant bacteria.

This case report describes a novel occurrence of a Grade III ankle sprain complicated by cellulitis. The patient ultimately required aspiration of an extra-articular fluid collection and treatment with parenteral antibiotics due to worsening of the infection despite treatment with second-generation cephalosporins. This individual's infection was consistent with MRSA-cellulitis. Cellulitis, in the context of a preceding ankle sprain, has not been reported in the literature; the resultant edema from the injury may have served as the nidus for infection. MRSA comprises a significant proportion of soft-tissue infections in the ambulatory setting, and physicians should incorporate this trend into therapeutic strategies for their infected patients.