Vasomotor reactivity as a predictor for syncope in patients with orthostatism.

OBJECTIVES: Syncope in patients with orthostatic hypotension (OH) may be the result of impaired cerebral autoregulation. Cerebral autoregulation status can be determined by assessing cerebral vasomotor reactivity (VMR). We assessed and compared VMR in patients with OH with and without syncope. MATERIAL AND METHODS: Twenty-nine patients with OH underwent transcranial Doppler (TCD) and the Diamox test (1 g acetazolamide IV) for assessing VMR during elaboration of their OH syndrome. The percent difference between cerebral blood flow velocities (BFV) in the middle cerebral (MCA) and vertebral (VA) arteries before and after acetazolamide was defined as VMR%. We considered increases of BFV of ≥ 40% as being indicative of good VMR and classified our study patients as having good or impaired VMRs accordingly. RESULTS: Mean VMR% values of the MCA and VA in patients with OH with syncope (n = 12) were significantly lower as compared with patients with OH without syncope (n = 17): 25.2 ± 20.5% and 42.5 ± 18.6%; 20.9 ± 15.5% and 40.8 ± 28.5%, respectively (P < 0.05). CONCLUSIONS: Among patients with OH, we found an association between the presence of syncope and impaired VMR. Assessment of VMR among patients with OH may predict those who are at higher risk to faint and fall and to support more aggressive intervention.

Isolated recurrent myelitis in a persistent MOG positive patient.

MOG-Ab positive CNS demyelination typically involves the optic nerve and spinal cord. Recurrent episodes of myelitis without optic neuritis are very rare and according to current literature review represent about 3-5% of positive MOG-Ab cases. We report a 30-year-old woman with positive serum MOG-Ab suffering two discrete episodes of transverse myelitis without ophthalmic involvement. Repeated serum MOG-Ab test after the second relapse was positive, correlating with high likelihood of relapsing disease. Of note, our patient relapsed under Rituximab therapy, which does not seem to be uncommon for MOG-Ab patients. Patients with isolated or recurrent myelitis without optic involvement should be screened for anti MOG IgG as a part of their workup.

Extra-cranial venous flow in patients with multiple sclerosis.

INTRODUCTION: Recently, a chronic state of impaired venous drainage from the central nervous system, termed chronic cerebrospinal venous insufficiency (CCSVI) was claimed to be a pathologic condition exclusively seen in patients with multiple sclerosis (MS), suggesting that cerebral venous congestion plays a significant role in the pathogenesis of MS. This hypothesis has gained enormous attention among patients and physicians but has been questioned since. METHODS: Twenty seven patients with MS and 32 healthy controls underwent color extra cranial Doppler exam aimed to detect four parameters of abnormal venous flow: no Doppler-detected flow in the IJV or vertebral veins (VV), reflux in the internal jugular veins (IJVs), venous flow stenosis in the IJVz (cross sectional area <0.3 cm) or reverted postural control in the IJV. RESULTS: Except for one healthy patient, blood flow direction in the IJVs was normal in all subjects. When aiming to detect at least one parameter of abnormal venous flow per subject, two parameters or three parameters no significant difference was found between subjects and controls (p = 0.707, 0.62, 0.849 respectively). CONCLUSION: We found no evidence to suggest that MS patients have excess of CCSVI. In addition we failed to observe a typical venous flow pattern in MS patients. Until carefully designed controlled studies to investigate CCVSI have been completed, invasive and potentially dangerous endovascular procedures as therapy for MS should be discouraged.