Trigeminal involvement detected by magnetic resonance imaging (MRI) in multiple sclerosis (MS) patients is usually associated with trigeminal neuralgia (TN) or painless paraesthesia in the trigeminal distribution. Our aim is to review the incidence of trigeminal involvement on MRI in a series of patients with MS at our institution, with further clinical correlation. We reviewed MRI scans of 275 MS patients for the presence of gadolinium enhancement on postcontrast T1-weighted images, anatomical and signal abnormalities on different sequences at the pontine trigeminal root entry zone (REZ) and in the cisternal portion of the nerves. We observed enhancement in the cisternal portion of the nerves and signal abnormalities (with or without enhancement) at the pontine trigeminal REZ in 8 (2.9%) patients, and enhancement was bilateral in 6 (75%) of those. Despite the inflammatory activity, none of them had TN and 3 (37.5%) had only painless paraesthesias in the correspondent V3 distribution. We also found a marked trigeminal hypertrophy in 2 (25%) patients, both with a longer period of disease. Our results confirm a high and clinically silent incidence of trigeminal involvement in MS patients, and suggest a simultaneous role of the central and peripheral type of myelin in trigeminal demyelination.

We demonstrated the importance of appropriate MRI sequences for diagnosis of the most frequent brain lesions in TS. Our study reinforces the fact that each sequence has a particular application according to the type of TS lesion. Gd injection might be useful in detecting SGCA; however, the parameters of size and location are also important for a presumptive diagnosis of these tumors.

BACKGROUND AND PURPOSE:Patients undergoing parenteral nutrition and those with portosystemic encephalopathy secondary to chronic liver disease and acquired and congenital portosystemic venous shunts frequently present manganese deposition in the basal ganglia, detected by MR imaging as hyperintense areas on T1-weighted sequences. We also observed similar abnormalities in the basal ganglia of patients with chronic renal failure undergoing maintenance hemodialysis. Our aim was to evaluate the pallidal signal intensity on T1-weighted images in a series of patients undergoing hemodialysis, with further evaluation of serum manganese levels and neurologic correlation, comparing them with patients with chronic renal failure without dialytic treatment.

The FLAIR sequence was superior for presumptive diagnosis and localization of acute and subacute low-grade SAH, representing a potential tool in this setting.

The clinical features of multiple system atrophy (MSA) include four domains: autonomic failure/urinary dysfunction, Parkinsonism, cerebellar ataxia, and corticospinal tract dysfunction. Although the diagnosis of definite MSA requires pathological confirmation, magnetic resonance imaging (MRI) studies have been shown to contribute to the diagnosis of MSA. Although pyramidal tract dysfunction is frequent in MSA patients, signs of pyramidal tract involvement are controversially demonstrated by MRI. We evaluated the pyramidal involvement in 10 patients (7 women) with clinically probable MSA, detecting the presence of spasticity, hyperreflexia, and Babinski sign, as well as demonstrating degeneration of the pyramidal tract and primary motor cortex by MRI in all of them. Our article also discusses key radiological features of this syndrome. In MSA, pyramidal tract involvement seems to be more frequent than previously thought, and the clinicoradiological correlation between pyramidal tract dysfunction and degeneration may contribute to the understanding of the clinical hallmarks of MSA. MRI may also add information regarding the differential diagnosis of this syndrome.