Tohru Terao

Transvenous Hemodynamic Assessment of Arteriovenous Malformations and Fistulas Preliminary Clinical Experience in Doppler Guidewire Monitoring of Embolotherapy

BACKGROUND AND PURPOSE Transvenous monitoring of blood flow through intracranial vascular malformations was performed with an intravascular Doppler guidewire to assess hemodynamic changes during endovascular embolotherapy. METHODS Flow velocity was assessed in the intracranial venous sinuses of two patients with arteriovenous malformations and seven patients with dural arteriovenous fistulas. In all cases, the Doppler guidewire was positioned in the dural sinuses coaxially through a 2.1F microcatheter. The Doppler guidewire was then advanced to the site of arteriovenous shunting for sampling of venous average peak velocity (APV) and pulsatility index. In two cases, simultaneous feeding artery flow velocity was monitored by transcranial color-coded duplex sonography. RESULTS Before embolotherapy, the flow pattern in the venous sinuses was pulsatile, with a mean (+/-SD) APV of 39.0 +/- 22.5 cm/s. Total or near-total embolization was achieved in six of the nine cases. After embolization, the flow pattern became less pulsatile and the APV was reduced to a mean of 21.2 +/- 14.6 cm/s (P = .0123, one-tailed paired t test). The pulsatility index was used to calculate the maximum minus the minimum peak velocity (MxPV-MnPV). This was reduced from an average of 27.0 +/- 8.7 cm/s to 13.5 +/- 8.3 cm/s after treatment (P = .0456). A parallel reduction in APV of the feeding arteries was observed with embolization. CONCLUSIONS Preliminary clinical experience indicates that transvenous assessment of two parameters, APV and MxPV-MnPV, is useful in the hemodynamic evaluation of intracranial arteriovenous shunts. This valuable hemodynamic information may be used for objective and quantitative monitoring during embolotherapy of intracranial vascular malformations.

Time dependent transition of the levels of protein-conjugated acrolein (PC-Acro), IL-6 and CRP in plasma during stroke

Objective Measurement of plasma levels of protein-conjugated acrolein (PC-Acro) together with IL-6 and CRP can be used to identify silent brain infarction (SBI) with high sensitivity and specificity. The aim of this study was to determine how these biomarkers vary during stroke. Methods Levels of PC-Acro, IL-6 and CRP in plasma were measured on day 0, 2, 7 and 14 after the onset of ischemic or hemorrhagic stroke. Results After the onset of stroke, the level of PC-Acro in plasma was elevated corresponding to the size of stroke. It returned to near control levels by day 2, and remained similar through day 14. The degree of the decrease in PC-Acro on day 2 was greater when the size of brain infarction or hemorrhage was larger. An increase in IL-6 and CRP occurred after the increase in PC-Acro, and it was well correlated with the size of the injury following infarction or hemorrhage. The results suggest that acrolein becomes a trigger for the production of IL-6 and CRP, as previously observed in a mouse model of stroke and in cell culture systems. The increase in IL-6 and CRP was also correlated with poor outcome judging from mRS. Conclusion The results indicate that the degree of the decrease in PC-Acro and the increase in IL-6 and CRP from day 0 to day 2 was correlated with the size of brain infarction, and the increase in IL-6 and CRP with poor outcome at discharge.

Spontaneous Hemorrhage of a Spinal Ependymoma in the Filum Terminale Presenting with Acute Cauda Equina Syndrome: Case Report

We present a rare case of spontaneous hemorrhage of a spinal ependymoma in the filum terminale presenting with acute cauda equina syndrome. A 16-year-old male presented with a sudden onset of severe back pain that began 10 days before hospitalization. This symptom progressed, followed by development of decreased sensation in the lower extremities, bladder dysfunction, and motor weakness that advanced to an inability to walk. Spinal magnetic resonance imaging revealed a hemorrhagic mass from Th12 to L2 and L4 to L5, and clinical signs indicated acute cauda equina compression. One day after admission to the hospital, emergency surgery was performed. A spinal tumor in the conus portion with a spinal subarachnoid hemorrhage was seen. Gross total excision of the massive hematoma mixed with the underlying tumor was performed. Pathological findings of the excised tumor demonstrated a WHO Grade II cellular ependymoma of the non-myxopapillary type. The patient made a significant recovery. The ability to walk was restored, and impaired bladder function improved at follow-up. Early diagnosis and suitable treatment are associated with a more favorable outcome.

O3-E-20. Intraoperative cochlear nerve mapping by cochlear nerve action potential

Methods for intraoperative mapping of the cochlear nerve (CN) in surgery for acoustic neurinoma (AN) have not yet been established. We attempted intraoperative mapping of the cochlear nerve by cochlear nerve action potential (CNAP) with a new recording probe. The subjects were 10 patients who had undergone surgery for AN using a retrosigmoid approach. Three of the 10 patients had severe hearing impairment so that CNAP data could not be obtained. In six of seven patients with useful hearing acuity, CN could be identified during surgery. However, CNAP was obtained in the nerves adjacent to CN. We could identify CN by the difference in waveforms between CN and the adjacent nerves. The recording probe was appropriate for mapping, but was inappropriate for functional monitoring. In contrast, conventional electrodes were more suitable for functional monitoring, but were not suitable for mapping. The combination of these electrode types would greatly improve the accuracy of monitoring. We performed CNAP by monopolar and bipolar recording. In bipolar recordings, the signal to noise ratio was higher than that in the monopolar recordings. The combination of monopolar and bipolar recordings would also improve the accuracy of monitoring.

43. Intraoperative cochlear nerve mapping by electrically evoked ABR

ease (PD). Overall 9 MSA patients and 23 PD patients were investigated regarding presences of RBD symptom, REM sleep without atonia (RWA), and the proportion of RWA during PSG (%RWA) at two separate occasions. In MSA patients, %RWA significantly increased from the baseline to the follow up (16.0 ± 19.4% to 31.0 ± 27.7%) whereas numbers of patients with RWA and RBD symptoms unchanged. On the other hand, in PD patients, %RWA and numbers of patients with RWA and RBD symptoms did not change. In conclusion, RBD symptoms in MSA may decrease in association with the aggravation of MSA despite increase in %RWA. However, RBD symptoms in PD patients may not change with the clinical course of PD.

Traumatic middle cerebral artery occlusion from boxing

A case of a traumatic middle cerebral artery occlusion resulting from a boxing injury is presented. A 22-year-old man, an amateur boxer, was admitted because of difficulty in speaking, that had appeared a day after a sparring fight. A computed tomographic scan showed low-density areas in the left globus pallidus and corona radiata. A carotid angiogram indicated complete occlusion of the left middle cerebral artery at its origin and an irregularity and narrowing of the left internal carotid artery in its supraclinoid portion. The patient was discharged 4 weeks after the admission with some persistent expressive dysphasia that diminished during the next month. The clinical features and mechanisms of the traumatic middle cerebral artery occlusion are discussed.