Structural connectivity changes in unilateral hearing loss.

Network connectivity, as mapped by the whole brain connectome, plays a crucial role in regulating auditory function. Auditory deprivation such as unilateral hearing loss might alter structural network connectivity; however, these potential alterations are poorly understood. Thirty-seven acoustic neuroma patients with unilateral hearing loss (19 left-sided and 18 right-sided) and 19 healthy controls underwent diffusion-weighted and T1-weighted imaging to assess edge strength, node strength, and global efficiency of the structural connectome. Edge strength was estimated by pair-wise normalized streamline density from tractography and connectomics. Node strength and global efficiency were calculated through graph theory analysis of the connectome. Pure-tone audiometry and word recognition scores were used to correlate the degree and duration of unilateral hearing loss with node strength and global efficiency. We demonstrate significantly stronger edge strength and node strength through the visual network, weaker edge strength and node strength in the somatomotor network, and stronger global efficiency in the unilateral hearing loss patients. No discernible correlations were observed between the degree and duration of unilateral hearing loss and the measures of node strength or global efficiency. These findings contribute to our understanding of the role of structural connectivity in hearing by facilitating visual network upregulation and somatomotor network downregulation after unilateral hearing loss.

Should trigeminal neuralgia be considered a clinically isolated syndrome?

The association between trigeminal neuralgia (TN) and multiple sclerosis (MS) is well established. Many MS patients with TN have magnetic resonance imaging (MRI) evidence of a symptomatic demyelinating lesion. Although infratentorial presentations are included in the diagnostic criteria for MS, there remains confusion in clinical practice as to whether TN should be considered a clinically isolated syndrome for the application of McDonald criteria. In this case series, we discuss this diagnostic quandary in patients presenting with TN and additional MRI findings suggestive of MS and highlight the unmet need for data in such patients to optimally guide their care.

The clinical and radiological features and prevalence of Neuro-Behçet's Disease: A retrospective cohort multicenter study in Saudi Arabia.

BACKGROUND: Neuro-Behçet's disease (NBD) is defined as primary neurological involvement in patients with systemic symptoms of BD. The variety of clinical presentations seen in NBD and the long list of similar conditions make diagnosis challenging. This retrospective study aimed to estimate the prevalence and describe neurological involvement in patients with Behçet's disease who presented to King Abdulaziz Medical Cities in Jeddah and Riyadh, Saudi Arabia. METHODS: This was a retrospective, cohort study which utilized a non-probability consecutive sampling technique to include all patients diagnosed with NBD patients. All patients with BD (215) were screened for neurological symptoms. Thirty-five patients were found to be diagnosed with NBD. Outcomes were estimated using the modified Rankin scale (mRS). RESULTS: In our cohort, one in six patients with BD was diagnosed with NBD. A total of 35 patients were diagnosed with NBD (mean age 27.56 ± 10.36 years; [2.88:1; Male: Female]). The main clinical features of NBD were headaches, weakness, unsteadiness, and dysarthria. The most commonly involved sites on imaging were the brainstem, diencephalon, cerebellum and basal ganglia. Oligocolonal bands were negative in all patients. Maintenance therapy most commonly included oral corticosteroids, azathioprine, and/or infliximab. Most patients received pulse corticosteroids alone when presenting with acute relapse. Half of our cohort was asymptomatic and three in four had favorable outcomes. CONCLUSION: NBD is common among patients with BD in our population with most patients having favorable outcomes. Patients might have a wide array of symptoms which might make the diagnosis challenging.

Cerebral Venous Sinus Thrombosis Secondary to Neurobrucellosis: A Case Report.

Brucellosis is a common infection that rarely causes cerebral venous sinus thrombosis (CVST). In this case, a 23-year-old male presented to the emergency department with status epilepticus. With a past medical history of drinking unpasteurized camel milk, elevated inflammatory markers, and evidence of brucellosis in the serum, the patient was diagnosed with brucellosis. Further investigations revealed left transverse sinus thrombosis extending to the jugular vein. The patient was treated with enoxaparin and a combination of doxycycline, ceftriaxone, and trimethoprim-sulfamethoxazole. This regimen led to rapid and significant clinical improvement in the signs and symptoms of the patient. CVST is a rare complication of neurobrucellosis that might present with signs and symptoms of meningitis. This case report highlights the importance of keeping neurobrucellosis as a possible cause of CVST in patients living in an area endemic to brucellosis.

Trigeminal neuralgia associated with a solitary pontine lesion: clinical and neuroimaging definition of a new syndrome.

Conventional magnetic resonance imaging of patients with trigeminal neuralgia (TN) does not typically reveal associated brain lesions. Here, we identify a unique group of TN patients who present with a single brainstem lesion, who do not fulfill diagnostic criteria for multiple sclerosis (MS). We aim to define this new clinical syndrome, which we term TN associated with solitary pontine lesion (SPL-TN), using a clinical and neuroimaging approach. We identified 24 cases of SPL-TN, 18 of which had clinical follow-up for assessment of treatment response. Lesion mapping was performed to determine the exact location of the lesions and site of maximum overlap across patients. Diffusion tensor imaging was used to assess the white-matter microstructural properties of the lesions. Diffusivity metrics were extracted from the (1) SPL-TN lesions, (2) contralateral, unaffected side, (3) MS brainstem plaques from 17 patients with TN secondary to MS, (4) and healthy controls. We found that 17/18 patients were nonresponders to surgical treatment. The lesions were uniformly located along the affected trigeminal pontine pathway, where the site of maximum overlap across patients was in the area of the trigeminal nucleus. The lesions demonstrated abnormal white-matter microstructure, characterized by lower fractional anisotropy, and higher mean, radial, and axial diffusivities compared with the unaffected side. The brainstem trigeminal fiber microstructure within a lesion highlighted the difference between SPL-TN lesions and MS plaques. In conclusion, SPL-TN patients have identical clinical features to TN but have a single pontine lesion not in keeping with MS and are refractory to surgical management.