A sequential study of visual evoked potential in patients with vitamin B12 deficiency neurological syndrome.

OBJECTIVE: Visual pathways are vulnerable to vitamin B(12) deficiency but there is paucity of studies evaluating visual evoked potential (VEP) changes following vitamin B(12) supplementation. Our aim was to evaluate the visual evoked potential changes in patients with vitamin B(12) deficiency neurological syndrome and their changes after vitamin B(12) therapy. METHODS: Seventeen patients with vitamin B(12) deficiency neurological syndromes diagnosed on the basis of megaloblastic bone marrow or low serum vitamin B(12) level or both were subjected to testing of visual acuity, field of vision, colour vision and neurological examination. Cranial magnetic resonance imaging was done in 9 patients and pattern reversal VEP was carried out on admission. P(100) latency and amplitude were measured. Visual function and VEP studies were repeated at 3 and 6 months after vitamin B(12) therapy. RESULTS: The patients' age ranged between 17 and 69 years; 7 were females and 16 were lactovegetarians. The duration of symptoms ranged between 10 days and 10 years. Visual acuity, colour vision, field of vision and fundus oculi were normal. VEP revealed prolongation of P(100) latency in 10 patients (17 eyes) which was mild in 2, moderate in 10 and marked in 5 eyes. Six months after treatment, P(100) latency improved to normal in all except 4 eyes. VEP abnormality was related to duration of illness and antiparietal cell antibodies. CONCLUSIONS: VEP is frequently prolonged in patients with vitamin B(12) deficiency neurological syndrome although asymptomatic. It usually returns to normal after treatment.     

Evoked potential changes in ischaemic myelopathy

Somatosensory evoked potentials are employed in the intraoperative monitoring but there is paucity of information about the motor evoked potentials (MEP) in spinal cord ischaemia. Two patients aged 9 and 4 years developed paraplegia following surgery for coarctation of aorta. The aortic cross clamping time in these patients was 100 min and 30 min. respectively. The patient with longer clamping time had flaccid paraplegia and lower limb MEPs were not recordable; whereas the patient with shorter clamping time had spastic paraparesis and prolonged CMCT to right lower limb. The latter patient improved significantly. Tibial SEPs were normal in both the patients. Our results suggest that MEP may have a greater role than SEP in documenting and prognosticating ischaemic myelopathy.     

SPECT changes and their correlation with EEG changes in tuberculous meningitis

OBJECTIVE: In tuberculous meningitis (TBM) blood flow may be altered due to associated vasculitis, hydrocephalus and raised intracranial pressure. Electroencephalography (EEG) and single photon emission computed tomography (SPECT) provide information about electrical activity and regional cerebral blood flow respectively. This study aims at the correlation of EEG and SPECT changes in patients with TBM. METHOD: Sixteen patients with TBM whose age ranged between 5 and 62 years and 3 of whom were females were subjected to clinical, radiological (CT and/or MRI), EEG and SPECT studies using 99mTc ethylene cystine dimer (ECD). Ten patients were in stage III and 3 each in stage II and stage I meningitis. Cranial CT scan was carried out in 15 and MRI in 4 patients. Hydrocephalus was present in 9, infarction in 7 and tuberculoma in 5 patients. RESULTS: SPECT studies were abnormal in all except 2 patients revealing basal ganglionic hypoperfusion in 14 and focal cortical hypoperfusion in 9 patients. The EEG was abnormal in 11 patients which included delta slowing in 5, theta slowing in 6, frontal intermittent rhythmic delta activity (FIRDA) in 3 and epileptiform discharges in 2 patients. All the patients with abnormal EEG had abnormal SPECT study except 1. In 4 patients, EEG was normal although there was subcortical hypoperfusion on SPECT. In spite of high frequency of focal cortical hypoperfusion (9 patients), EEG revealed focal abnormality in 3 patients only. CONCLUSION: It can be concluded that the SPECT reveals more frequent abnormalities compared to EEG and CT scan. Cortical hypoperfusion with or without basal ganglia hypoperfusion is associated with FIRDA and diffuse delta slowing on EEG.     

Vitamin B12 deficiency neurological syndromes: a clinical,MRI and electrodiagnostic study

BACKGROUND: Vegetarianism is an important cause of vitamin B12 deficiency, especially in countries like India. We managed 17 patients with neurological syndrome due to vitamin B12 deficiency in a tertiary care referral teaching hospital which caters to relatively affluent population. AIM: To evaluate neurophysiological and MRI changes in patients presenting with vitamin B12 deficiency neurological syndrome and interpret these is the light of reported autopsy findings. SETTING: Tertiary care referral teaching hospital. METHODS: Patients with vitamin B12 deficiency neurological syndrome diagnosed by low serum vitamin B12 and/or megaloblastic bone marrow were subjected to clinical evaluation and spinal MRI. The neurophysiological tests included nerve conduction studies, tibial somatosensory evoked potential (SEP), motor evoked potential (MEP) and visual evoked potential (VEP) studies. The recovery was defined on the basis of 6 months Barthel Index score into complete, partial or poor. RESULTS: There were 17 patients with vitamin B12 deficiency neurological syndrome, 3 were females and 12 lactovegetarian. The clinical syndrome was that of myelopathy in 8, myeloneuropathy in 5, dementia myelopathy in 3 and neuropathy in 1 patient. All the patients had impaired joint position and vibration sensation in the lower limbs and 4 had in upper limbs as well. Lower limbs were spastic in 13 and upper limbs in 2 patients. Spinal MRI revealed T2 hyperintensity in cervicodorsal region in 6 and cord atrophy in 3 patients. Sural nerve conduction was abnormal in 8 and peroneal conduction in 5 patients. In one patient all sensory nerve conductions were unrecordable but motor conductions were normal. Tibial SEP was abnormal in 12 out of 15 and lower limb MEP in 8 out of 12 patients. P100 latency of VEP was prolonged in 7 out of 13 patients. Right to left asymmetry was present in tibial SEP in 4 and VEP in 2 patients. At 6 months followup 2 patients improved completely, 7 partially and 3 had poor recovery. Clinical recovery correlated with MEP but not with SEP or MRI changes. CONCLUSION: The evoked potential and MRI changes in vitamin B12 deficiency neurological syndrome are consistent with focal demyelination of white matter in spinal cord and optic nerve. Myelopathic presentation is commoner and SEP is more frequently abnormal. The outcome at 6 months correlated with MEP changes.     

Comparison of electrocautery versus holmium laser energy source for transurethral ureterocele incision: an outcome analysis from a tertiary care institute

Lasers in Medical Science - Transurethral endoscopic incision is an established treatment option for management of obstructing ureterocele. It can be performed using monopolar electrocautery or...     

Role of clinical, radiological, and neurophysiological changes in predicting the outcome of tuberculous meningitis: a multivariable analysis

OBJECTIVES: The role of EEG and evoked potentials has not been evaluated in predicting the prognosis of tuberculous (TB) meningitis. The present study was aimed at evaluating the prognostic significance of clinical, radiological, and neurophysiological variables using multi-variable analysis. METHODS: Patients with TB meningitis diagnosed on the basis of clinical, radiological, and CSF criteria have been prospectively evaluated. All the patients were subjected to a detailed neurological evaluation. The outcome was defined 6 months after starting treatment on the basis of the Barthel index (BI) score into poor (BI <12) and good recovery (BI> or =12). Death was included in the poor recovery group for statistical analysis. Thirteen clinical (age, sex, seizure, focal weakness, stage of meningitis, Glasgow coma scale score, methyl prednisolone therapy), CT (infarction, hydrocephalus, tuberculoma) and neurophysiological (EEG, motor and somatosensory evoked potentials) variables were evaluated employing single variable logistic regression followed by multivariable logistic regression analysis. The best set of predictors were obtained by stepdown logistic regression analysis. RESULTS: Fifty four patients were included in the present study. Their age ranged between 5 and 62 years, 11 were children younger than 12 years and 14 were female. Nine patients were in stage I meningitis, 12 in stage II, and 33 in stage III. On single variable logistic regression analysis the significant predictors of 6 months outcome of TB meningitis included focal weakness, Glasgow coma scale (GCS), motor evoked potential (MEP) and somatosensory evoked potential (SEP). On multivariable analysis the best set of predictors comprised focal weakness, GCS, and SEP. CONCLUSIONS: In patients with TB meningitis focal weakness, GCS, and SEP are the best predictors of 6 month outcome.     

The partial portosystemic shunting and its hemodynamic consequences

Complex hemodynamical investigations were done in 32 patients in 1985-1999 yr. period before the operation, in 6-8 and 12-24 mo after performance of the partial portosystemic shunting operation (in 8 patients mesentericocaval anastomosis was formed, in 10--central splenorenal anastomosis, in 12--splenorenal anastomosis side to side and in 2--lowermesentericorenal anastomosis). The performance of shunting operation had promoted the lowering of the blood flow volumetric velocity and of the pressure in v. cava as well, its diameter reduction, the lowering of general hepatic blood flow. The lowering of blood flow in the v. cava system after the shunting operation performance caused the arterial hepatic blood flow enhancement occurrence.     

Knowledge and Attitudes About Pre-Exposure Prophylaxis Among Young Adults Experiencing Homelessness in Seven U.S. Cities

Purpose

Evidence suggests that young adults experiencing homelessness (YEH) are at elevated risk of HIV compared to housed youth. Given the limited research on pre-exposure prophylaxis (PrEP) awareness among YEH, this study examined their PrEP knowledge and attitudes.

Predictors of outcome of myasthenic crisis

There is paucity of study on predictors of myasthenic crisis (MC), prolonged ventilation and their outcome, a reason why this study was undertaken. Sixty-four patients with myasthenia gravis (MG) were included whose median age was 45 (6–84) years. Their clinical treatment, presence of thymoma, anti-acetylcholine receptor antibody (AchRAb), thymectomy, comorbidities, offending drugs and occurrence of MC were noted. Patients needing prolonged ventilation (>15 days) were noted. Hospital mortality, MG quality of life (QOL) at discharge and thereafter annual hospital visit, admission, expenditure and work day loss were enquired. Fourteen (21.9 %) patients had MC within 1–120 (median 8.5) months of disease onset within a median follow-up of 48 (3–264) months. The precipitating factors were infection in six, surgery in five, tapering of drugs in two and reaction to iodinated contrast in one patient. Male gender, bulbar weakness, AchRAb, thymoma, surgery and comorbid illnesses were related to MC. Eight of them (57.1 %) needed prolonged ventilation. Half the patients with MC had recurrent crisis (2–4 attacks). Death was not related to MC although MC patients had worse QOL, higher annual treatment expenditure with frequent hospital visit and hospitalization. In conclusion, association of comorbid illness with MC and prolonged ventilation highlights the need of close follow-up and appropriate management.