Elective brachial plexus decompression in neurogenic thoracic outlet syndrome.

We aimed to evaluate functional outcome following elective brachial plexus decompression by compressive fibrous band resection and limited on-demand bone abnormality resection in patients with neurogenic thoracic outlet syndrome (N-TOS). A retrospective continuous observational study was conducted in 17 patients (15 women and 2 men), with a mean age of 42 years, operated on between 2013 and 2021. Twenty brachial plexus decompressions were performed, for 13 objective and 7 subjective N-TOSs, including 3 recurrent N-TOSs. At last follow-up, outcomes were evaluated in terms of residual pain, paresthesia and hand motor deficit, plus patient-reported assessment and Quick-DASH functional scoring. No postoperative complications occurred. At a median follow-up of 12 months (range 6-48 months), complete pain relief and paresthesia resolution were found in 11/15 and 9/14 cases, respectively. All patients reported that their symptoms had improved. In contrast, hand muscle atrophy persisted in all cases (n = 11). Sensorimotor recovery seemed to be poorer and mean Quick-DASH score better in objective than subjective N-TOS patients. Elective brachial plexus decompression seemed to be a safe procedure, providing constant improvement in subjective symptoms related to lower trunk irritation. However, nerve release did not provide hand muscle recovery in patients with objective N-TOS. LEVEL OF EVIDENCE: IV.

Neurolymphomatosis related to direct epineural invasion of the superficial peroneal nerve from subcutaneous B-cell lymphoma.

Neurolymphomatosis is a rare complication of systemic lymphomas, and is classically related to hematogenous spread or intraneural spread of tumor cells from the leptomeninges. Here we report a case of neurolymphomatosis related to direct epineural invasion of the superficial peroneal nerve from subcutaneous localization of B-cell lymphoma. Nerve biopsy revealed striking histological features suggestive of contiguous infiltration of the superficial peroneal nerve by subcutaneous lymphoma. We think this case report sheds new light on neurolymphomatosis pathophysiology with an unreported mechanism in B-cell lymphoma. It also points out that the clinical spectrum in neurolymphomatosis is really variable, pure sensory mononeuritis being a rare presentation. Finally, our case is also strongly illustrative of the contribution of early nerve ultrasonography in the patient diagnosis and in guidance of the nerve biopsy.

Advanced multiparametric magnetic resonance imaging of multinodular and vacuolating neuronal tumor.

BACKGROUND AND PURPOSE: Multinodular and vacuolating neuronal tumor (MVNT) of the cerebrum is a rare brain lesion with suggestive imaging features. The aim of our study was to report the largest series of MVNTs so far and to evaluate the utility of advanced multiparametric magnetic resonance (MR) techniques. METHODS: This multicenter retrospective study was approved by our institutional research ethics board. From July 2014 to May 2019, two radiologists read in consensus the MR examinations of patients presenting with a lesion suggestive of an MVNT. They analyzed the lesions' MR characteristics on structural images and advanced multiparametric MR imaging. RESULTS: A total of 64 patients (29 women and 35 men, mean age 44.2 ± 15.1 years) from 25 centers were included. Lesions were all hyperintense on fluid-attenuated inversion recovery and T2-weighted imaging without post-contrast enhancement. The median relative apparent diffusion coefficient on diffusion-weighted imaging was 1.13 [interquartile range (IQR), 0.2]. Perfusion-weighted imaging showed no increase in perfusion, with a relative cerebral blood volume of 1.02 (IQR, 0.05) and a relative cerebral blood flow of 1.01 (IQR, 0.08). MR spectroscopy showed no abnormal peaks. Median follow-up was 2 (IQR, 1.2) years, without any changes in size. CONCLUSIONS: A comprehensive characterization protocol including advanced multiparametric magnetic resonance imaging sequences showed no imaging patterns suggestive of malignancy in MVNTs. It might be useful to better characterize MVNTs.

Multinodular and Vacuolating Posterior Fossa Lesions of Unknown Significance.

Multinodular and vacuolating neuronal tumor of the cerebrum is a rare supratentorial brain tumor described for the first time in 2013. Here, we report 11 cases of infratentorial lesions showing similar striking imaging features consisting of a cluster of low T1-weighted imaging and high T2-FLAIR signal intensity nodules, which we referred to as multinodular and vacuolating posterior fossa lesions of unknown significance. No relationship was found between the location of the lesion and clinical symptoms. A T2-FLAIR hypointense central dot sign was present in images of 9/11 (82%) patients. Cortical involvement was present in 2/11 (18%) of patients. Only 1 nodule of 1 multinodular and vacuolating posterior fossa lesion of unknown significance showed enhancement on postcontrast T1WI. DWI, SWI, MRS, and PWI showed no malignant pattern. Lesions did not change in size or signal during a median follow-up of 3 years, suggesting that multinodular and vacuolating posterior fossa lesions of unknown significance are benign malformative lesions that do not require surgical intervention or removal.

Significance of acute multiple infarcts in multiple cerebral circulations on initial diffusion weighted imaging in stroke patients.

OBJECTIVES: We attempted to assess the frequency, clinical and neuroradiological features of concomitant Acute Multiple Infarcts in Multiple Cerebral Circulations (AMIMCC) and to classify their causes. SUBJECTS AND METHODS: Consecutive patients treated for MR DWI-confirmed infarcts were included in this cohort. We retrospectively analyzed all patients with AMIMCC of our prospective database, studying clinical and radiological features. Causes of stroke were classified using TOAST and ASCO system (atherosclerosis, small vessel disease, cardiac source, other causes). RESULTS: Eighty AMIMCC were identified out of 824 consecutive patients with MR DWI-confirmed infarcts (9.7%). Compared with single infarct patients, AMIMCC patients presented similar age and risk factors. Only 24 AMIMCC patients (30%) presented symptoms suggesting multiple lesions before MRI. Cardiac origin existed in 39 of 80 patients (49%) including atrial fibrillation in 25 patients. Other sources of AMIMCC were hematologic diseases or coagulopathies such as intravascular coagulation in relation with cancer (n = 6; 7,5%) and vasculitis or systemic disorders (n = 5;6,5%). AMIMCC also appeared to originate from unilateral carotid diseases or intracranial stenosis, mostly atheromatous, in association with anatomic variations(n = 9;11%). In 21 patients, no cause was identified despite extensive investigations (26%). According to TOAST classification, 62% had a definite source for infarcts, 67% according to ASCO grade 1 classification. MRI data did not permit to orientate etiological explorations according to DWI appearance, associated leucoaraiosis or previous infarcts on FLAIR or microbleeding on gradient-echo sequences. CONCLUSIONS: AMIMCC are not rare and mostly need MRI to be detected. Multiple and various etiologies are implicated, including cardioembolic diseases in half of them, but also hematologic disorders and angeitis.