gms | German Medical Science

57th Annual Meeting of the German Society of Neurosurgery
Joint Meeting with the Japanese Neurosurgical Society

German Society of Neurosurgery (DGNC)

11 - 14 May, Essen

Changes of subcortical CBF and cortical O2-Saturation following resection of cerebral AVM indicate a distinct pattern of reactive hyperemia

Veränderungen des subkortikalen CBF und der kortikalen Sauerstoffsättigung nach AVM-Resektion deuten auf eine spezifische Form der reaktiven Hyperämie bei diesen Patienten

Meeting Abstract

  • corresponding author B. Meyer - Neurochirurgische Universitätsklinik Bonn
  • C. Stüer - Neurochirurgische Universitätsklinik Bonn
  • T. Ikeda - Neurochirurgische Universitätsklinik Bonn
  • M. Stoffel - Neurochirurgische Universitätsklinik Bonn
  • C. Schaller - Neurochirurgische Universitätsklinik Bonn

Deutsche Gesellschaft für Neurochirurgie. Japanische Gesellschaft für Neurochirurgie. 57. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie e.V. (DGNC), Joint Meeting mit der Japanischen Gesellschaft für Neurochirurgie. Essen, 11.-14.05.2006. Düsseldorf, Köln: German Medical Science; 2006. DocSA.02.08

The electronic version of this article is the complete one and can be found online at:

Published: May 8, 2006

© 2006 Meyer et al.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License ( You are free: to Share – to copy, distribute and transmit the work, provided the original author and source are credited.



Objective: To test the hypothesis that the reactive hyperemia after resection of uncomplicated AVMs differs from the one seen after intracranial surgery for nonvascular lesions (i.e. transsylvian dissection).

Methods: Cortical O2 Saturation (=SO2) via Spectrophotometry (EMPHO II™) and subcortical CBF (TD-rCBF) via thermal diffusion flowmetry (Bowman Thermoflow™) were measured intraoperatively before and after resection in n=12 patients with small/medium-sized AVM and transsylvian dissection in n=15 patients with nonvascular lesions (=controls). All data were pooled according to groups and times, and compared via ANOVA (p<0.05) plus a post-hoc Dunnet correction for multiple comparisons. All data (given below as means ±SD) were collected in the context of a prospective study.

Results: All physiological variables were comparable among groups and times. SO2 values in the perisylvian cortex or around AVM increased in both groups significantly (AVM pre: 52.4±12.5%SO2 post:71.4±7.4%SO2, Control pre: 57.1±8.4%SO2 post:69.9±8.7%SO2). However, white matter blood flow at the distance of >3 cm from the malformation or Sylvian fissure increased significantly only in the AVM group (AVM pre: 18.9±6.6 ml/100g/min post:26.2±6.9 ml/100g/min, Control pre: 20.1±7.6 ml/100g/min post:19.4±7.8 ml/100g/min). Continuous measurements in the AVM group during the procedures showed a steady increase of CBF to post-resection values during AVM obliteration. A retraction-induced decrease of CBF was observed in the control group, which recovered almost to baseline after spatula release.

Conclusions: These results indicate that reactive hyperemia after transient ischemia due to retraction is a)regionally confined and b)equivalent to relative hyperemia, in which supply momentarily exceeds the reduced demand. In contrast to that an absolute increase of blood flow occurs in the environment, even after the obliteration of small, uncomplicated AVMs. The long-lasting nature of the mechanisms compensating for reduced perfusion pressure in AVM patients is most likely responsible for this difference.