Bilateral dural arteriovenous fistula diagnosed with neurovascular ultrasonography.

BACKGROUND: Intracranial dural arteriovenous fistulas (dAVFs) are pathological anastomoses between meningeal arteries and dural venous sinuses or cortical veins. Diagnosis of dAVFs can be challenging due to their broad range of clinical manifestations and the lack of specificity in their symptoms. We present a rare case of a patient with bilateral dAVFs, who was referred to our department for carotid doppler ultrasonography/transcranial color Doppler. CASE REPORT: A 67-year-old man was referred by his treating physician for neurovascular ultrasonography due to vision impairment associated with papilledema of both eyes. On ultrasound examination both external carotid arteries showed a "pseudo-internalization" pattern with high end-diastolic velocities and reduced resistance indices. Subsequent magnetic resonance and digital subtraction angiography revealed dAVF of both transverse sinuses, with occipital and medial meningeal arteries as feeders. CONCLUSIONS: Neurovascular sonography may serve as a screening and follow-up tool when a DAVF in the transverse sinus/sigmoid sinus is suspected.

There is No Association between Cardiovascular Autonomic Dysfunction and Peripheral Neuropathy in Chronic Hemodialysis Patients

BACKGROUND AND PURPOSE: The potential association between the severity of autonomic dysfunction and peripheral neuropathy has not been extensively investigated, with the few studies yielding inconsistent results. We evaluated the relationship between autonomic dysfunction and peripheral neuropathy in chronic hemodialysis patients in a cross-sectional study. METHODS: Cardiovascular autonomic function was assessed in 42 consecutive patients with chronic renal failure treated by hemodialysis, using a standardized battery of 5 cardiovascular reflex tests. Symptoms of autonomic dysfunction and of peripheral neuropathy were evaluated using the Autonomic Neuropathy Symptom Score (ANSS) and the Neuropathy Symptoms Score. Neurological deficits were assessed using the Neuropathy Disability Score. Conduction velocities along the sensory and motor fibers of the sural and peroneal nerves were measured. Thermal thresholds were documented using a standardized psychophysical technique. RESULTS: Parasympathetic and sympathetic dysfunction was prevalent in 50% and 28% of cases, respectively. Peripheral neuropathy was identified in 25 cases (60%). The prevalence of peripheral neuropathy did not differ between patients with impaired (55%) and normal (75%) autonomic function (p=0.297; Fisher's exact test). The electrophysiological parameters for peripheral nerve function, neuropathic symptoms, abnormal thermal thresholds, age, gender, and duration of dialysis did not differ significantly between patients with and without autonomic dysfunction. Patients with autonomic dysfunction were more likely to have an abnormal ANSS (p=0.048). The severity of autonomic dysfunction on electrophysiological testing was positively correlated with ANSS (r=0.213, p=0.036). CONCLUSIONS: The present data indicate that although cardiovascular autonomic dysfunction is prevalent among patients with chronic renal failure, it is not associated with the incidence of peripheral neuropathy.