gms | German Medical Science

62nd Annual Meeting of the German Society of Neurosurgery (DGNC)
Joint Meeting with the Polish Society of Neurosurgeons (PNCH)

German Society of Neurosurgery (DGNC)

7 - 11 May 2011, Hamburg

Monitoring regional cerebral blood flow in balloon test occlusion as a diagnostic tool for therapeutical triage of patients with planned sacrifice of the internal carotid artery

Meeting Abstract

Search Medline for

  • D. Frey - Klinik für Neurochirurgie, Charité - Universitätsmedizin Berlin
  • G. Bohner - Klinik für Radiologie, Charité - Universitätsmedizin Berlin
  • P. Horn - Klinik für Neurochirurgie, Charité - Universitätsmedizin Berlin
  • P. Vajkoczy - Klinik für Neurochirurgie, Charité - Universitätsmedizin Berlin

Deutsche Gesellschaft für Neurochirurgie. Polnische Gesellschaft für Neurochirurgen. 62. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie (DGNC), Joint Meeting mit der Polnischen Gesellschaft für Neurochirurgen (PNCH). Hamburg, 07.-11.05.2011. Düsseldorf: German Medical Science GMS Publishing House; 2011. DocP 007

doi: 10.3205/11dgnc228, urn:nbn:de:0183-11dgnc2285

Published: April 28, 2011

© 2011 Frey 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 integrate a novel method of monitoring regional cerebral blood flow (rCBF) during balloon test occlusion (BTO) into the algorithm for indication of extracranial-intracranial (EC/IC) bypass surgery in patients with cerebral aneurysms necessitating vessel sacrifice.

Methods: Nineteen consecutive patients (11 female, 8 male, age: 14–77 yrs) with cerebral aneurysms whose treatment necessitated the sacrifice of a major brain-supplying vessel were included in this study. All patients underwent BTO for 20 minutes while performing diagnostic cerebral angiography. Besides clinical and angiographic examination to test hemodynamic tolerance during BTO, rCBF was monitored by a thermodiffusion probe that had been inserted in the related MCA vascular territory of the affected vessel. rCBF measurements were calculated as an increase or decrease in percentage points referring to baseline values of each individual patient during BTO. For patients showing no clinical or quantitative signs of hemodynamic intolerance during 20min of BTO a hemodynamic challenge was performed by administration of acetazolamide (1 mg/kg/b.w., i.v.).

Results: In all cases we could obtain continuous, quantitative and reliable baseline values of rCBF between 23 and 58 ml/min/100g prior to BTO. We experienced no complications as a result of probe placement procedures. Due to clinical neurological deficits during BTO in 2 patients (aphasia, dysesthesia of the left leg), further examination was discontinued in these patients. In all other patients, no neurological deficits were evoked. In 4 (21%) patients we found no change in rCBF during balloon test occlusion for 20 minutes. 2 patients in this group did not show any decrease in CCBF or clinical symptoms even after acetazolamide challenge, whilst 2 in this group showed a decrease of 20% and 25%, respectively. 7 (37%) of the patients showed a decrease of up to 30%. In 5 (26%) we found a decrease of 30–60% from baseline value. In 1 patient rCBF dropped by more than 60% from baseline. EC/IC bypass procedure was decided according to risk stratification based on rCBF measurements and the overall interpretation of the individual patient.

Conclusions: Monitoring of rCBF as a real-time, direct, quantitative and continuous monitoring technique during balloon test occlusion provides a valuable asset and an essential parameter for the therapeutical triage of patients with planned sacrifice of the internal carotid artery.