The diagnostic accuracy and era for improvement for frameless stereotactic brain biopsy: a series of 109 procedures and a systemic review

Abstract PurposeTo evaluate the diagnostic accuracy of frameless stereotactic brain biopsy and review the era for improvement.MethodsThis is a prospectively collected cohort study from 2007 to 2020. We reviewed patients who received frameless stereotactic brain biopsy in Prince of Wales Hospital and evaluated the diagnostic accuracy of the frameless stereotactic brain biopsy procedures. The biopsy result was classified into conclusive, inconclusive or negative, based on the pathological, radiological and clinical diagnosis concordance. For inconclusive or negative results, we further evaluated the pre-operative planning and post-operative imaging to review if further improvement could be made. The complication rate of symptomatic hemorrhage and mortality rate was also analyzed.ResultsThere were 106 patients with 109 biopsy procedures performed from 2007 to 2020. The conclusive diagnosis was reached in 103 (94.5%) procedures. The inconclusive diagnosis was noted in four (3.7%) procedures and negative diagnosis was yielded in two (1.9%) procedures. Symptomatic hemorrhage was noted in one patient (0.9%). There was no mortality case (0.0%) in our case series. The registration errors occurred in three cases (2.8%), sampling of the non-representative part of the lesion occurred in two cases (1.8%), and one biopsy (0.9%) for lymphoma was negative after the commencement of steroids. Systemic review showed that the diagnostic accuracy under the structurally defined diagnosis criteria was comparable with published literatures in recent ten years.ConclusionThe stereotactic biopsy is a safe procedure with high diagnostic accuracy only if meticulous pre-operative planning and careful intra-operative registration is performed. The common pitfalls precluding a conclusive diagnosis are errors during registration and non-representative biopsy sites.