Intraoperative neurophysiological monitoring during urgent surgical extracranial internal carotid artery recanalization.

OBJECTIVE: The clinical outcome of surgical extracranial internal carotid artery (eICA) recanalization may be adversely affected by intraoperative ischemia. Median nerve somatosensory evoked potential (SEP) amplitude correlates well with cerebral blood flow. Our study presents the value of intraoperative SEP and selective shunting in the prevention of intraoperative ischemia development during urgent eICA recanalization. METHODS: Prospective recruitment of patients with acute unilateral eICA occlusion. All underwent surgical recanalization with intraoperative monitoring of scalp median SEPs. Preoperative clinical findings, cerebral collaterals, and 3 month functional outcome were evaluated. RESULTS: The cohort consisted of 33 patients. Intraoperative SEP amplitude decreased significantly in 6 (18.2%). An intraluminal shunt was inserted twice (6.1%), surgical complications occurred in 6 (18.2%), intracerebral hemorrhage was not found. Favorable outcome 3 months after surgery according to the modified Rankin scale (mRS 0-2) was achieved in 28 (84.8%), 3 patients died (9.1%). CONCLUSIONS: Intraoperative SEP during urgent eICA recanalization seems to be beneficial. Thanks to the effective measure based on the intraoperative SEP changes, the clinical outcome in four(12.1%) could be positively affected. SIGNIFICANCE: The results suggest that selective shunting based on intraoperative median SEPs may prevent intraoperative ischemia and may improve overall outcome of urgent eICA recanalization.

Changes in Cognition and Hemodynamics 1 Year after Carotid Endarterectomy for Asymptomatic Stenosis.

OBJECTIVES: The impact of a change in hemodynamics on cognitive skills in patients with asymptomatic carotid stenosis (ACS) after carotid endarterectomy (CEA) remains unclear. The aim of this study was to evaluate the results of CEA for ACS at 1 year by assessing the changes in anterior, middle, and posterior cerebral artery blood flow in tandem with changes in cognitive efficiency. METHODS: Flow volume in cerebral arteries using quantitative magnetic resonance angiography was measured in a group of 14 males and 5 females before and at 1 year after CEA for ACS. Cognitive efficiency was assessed by Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). The values of flow volume were processed using simple ratio (SR) and were used for covariance analyses with changes in cognitive skills after CEA. RESULTS: A significant improvement in cognitive efficiency indexes of immediate memory and visuospatial perception at 1 year after CEA for ACS was observed. Simultaneously, a significant deterioration of speech index was noted. During the analysis of association between flow and cognition, the highest correlation could be seen between the middle cerebral artery (MCA) flow and the visuospatial perception. A change in posterior cerebral artery (PCA) flow was associated with an increase in immediate memory index and anterior cerebral artery (ACA) flow change with the speech index. CONCLUSION: Convergence of data supporting the association between revascularization and cognitive improvement were added in a small, single-center cohort of ACS patients undergoing CEA. No significant differences in cognition were seen between preoperative findings and at 1 year after CEA. Visuospatial perception improvement was linked to flow change in MCA, immediate memory improvement to flow change in PCA, and speech index change to flow change in ACA. Methodical limitations of this small study preclude formulating larger generalizations. Hemodynamic factors in CEA should be assessed in a larger-scale study.

Blood Flow Volume Measurement in Cervical and Intracranial Arteries using Quantitative Magnetic Resonance Angiography and Duplex Sonography (Bocaccia) - A Prospective Observational Study.

PURPOSE: Cerebral blood flow volume is an important factor for the accurate diagnosis of neurovascular diseases and treatment indication. This study aims to assess correlations of blood flow volume measurements in cervical and intracranial arteries between duplex sonography and quantitative magnetic resonance angiography (qMRA). MATERIALS AND METHODS: Consecutive patients with suspicion of cerebral vascular pathology underwent qMRA and duplex sonography of cervical and intracranial arteries with measurement of blood flow volume in bilateral common (CCA), internal (ICA) and external carotid arteries, vertebral and basilar arteries, middle, anterior, posterior cerebral and posterior communicating arteries using 2 different ultrasound machines. Ten patients underwent all examinations twice. Correlations between blood flow volume measurements were evaluated using Spearman's correlation coefficient and inter-class correlation coefficient (ICC). RESULTS: In total, 21 subjects (15 males, mean age: 56.3 ± 6.2 years) were included in the study. Duplex sonography inter-investigator correlation was excellent (ICC = 0.972, p < 0.0001) as well as intra-investigator correlations of both qMRA and duplex sonography (ICC ˃ 0.990, p < 0.0001). Mostly high correlations were recorded between qMRA and duplex sonography in particular cervical arteries but only low to moderate correlations were obtained for intracranial arteries. The mean differences between blood flow volume measurements were 10.9 ±â€Š8.1 % in the CCA and its branches when using qMRA and 15.0 ±â€Š11.9 % when using duplex sonography, 13.5 ±â€Š11.8 %/35.4 ±â€Š34.2 % in the ICA siphon and its branches when using qMRA/duplex sonography, and 24.1 ±â€Š19.7 %/44.9 ± 44.0 % in both vertebral arteries and the basilar artery when using qMRA/duplex sonography. CONCLUSION: Duplex sonography as well as qMRA allow for highly reproducible measurement of blood flow volume in cervical and intracranial arteries in routine clinical practice.

Encephalitozoon cuniculi genotype I as a causative agent of brain abscess in an immunocompetent patient.

A brain abscess caused by Encephalitozoon cuniculi genotype I together with Streptococcus intermedius occurred in a patient without major immunocompromise and with diabetes. The distinguishing clinical signs were hemiparesis and epilepsy. The microsporidium was observed in the abscess aspirate, and its specific DNA was also detected in stool and urine. The patient was successfully treated with albendazole and mebendazole.