The risk of haemorrhage after image guided stereotactic biopsy of intra-axial brain tumours - A prospective study

Objective. To analyze prospectively the frequency and the risk of symptomat ic and asymptomatic haemorrhage after image guided stereotactic biopsy of i ntra-axial brain tumours. Methods. The study was conducted within a time frame of 24 months (April 19 98-April 2000). 326 patients (150 males. 176 females; mean age 56.8 years) were included and 335 computerized tomography (CT)-guided stereotactic biop sies were performed/supervised by a specialized stereotactic neurosurgeon. A modified Riechert Stereotaxy System and a workstation for multiplanar tra jectory planning were used in all patients. Serial biopsies (median, 5 samp les) were done with small forceps (diameter 1 mm), smear preparations of th e biopsy specimens were intra-operatively examined. Frequency. size, and lo cation of any detectable bleeding were analyzed by post-biopsy CT-scan inve stigation. For risk estimation, logistic regression analysis was performed. The chi-square statistic was used for comparative analysis of the study re sults with available data from the literature. Results A conclusive tissue diagnosis could be achieved in 98%. Overall tre atment morbidity was 3.1%. There was no mortality. Haemorrhage related morb idity was 0.9%. Age, Karnofsky score, mass effect of the tumour. tumour his tology, tumour location and the number of specimens taken did not have any prognostic significance. The clinically silent bleeding rate was 9.6% and m ore often seen in patients with high grade gliomas (p = 0.03). Both the sil ent and non-silent bleeding rate were significantly lower as compared to av ailable prospective data in the literature. (p < 0.01). Conclusion. Using multiplanar image guided trajectory planning. small biops y forceps and intra-operative smear preparations the risk of major haemorrh age related morbidity after stereotactic brain tumour biopsy is extremely l ow (<1%) in experienced hands.