Background

CT-guided spinal biopsy (soft tissue core/bone/aspiration) is an important and commonly used radiological diagnostic procedure for investigation of malignant and infectious spinal pathology. We evaluated the diagnostic yield and complication rate of biopsies performed at a major tertiary neurosciences centre against the meta-analysis of 2021 by Michalopoulos et al [1] which showed 91% diagnostic yield and 1% complication rate.

Objective

To determine the diagnostic yield, most common indications, complication rate and possible reasons for inconclusive results on histology.

Methods

Retrospective analysis of a total of 107 CT-guided spinal biopsies performed at UHNM between May 2019 and May 2022. For all cases, we assessed the indication and site of biopsy, type/size of needle used, complications, histology result, any technique related factors that may have contributed to inconclusive histology as well as whether repeat biopsy was required.

Results

81% (84 out of 104) of first-attempt biopsies had a positive diagnostic yield on histology and 100% of repeat biopsies (3 out of 3) were diagnostically accurate. There were 3 indications for spinal biopsy at our centre: investigation of infection, malignancy and inconclusive first-attempt biopsy. 69% of biopsies were performed for malignancy and 28% for infection. Our centre had a <1 % complication rate. 25% (5 out of 20) of initially inconclusive cases, of which only 3 were re-biopsied, could be attributed to technique-related factors. The remaining 75% (15 out of 20) were either not attributable to technique (i.e. histology related), did not have appropriately saved images or classed as truly difficult by an expert operator (i.e. upper cervical spine location).

Conclusions

Out of the total 107 biopsies performed, there was a diagnostic yield of 81% (87 out of 107) including repeat biopsies. Overall, we are approaching the diagnostic yield as per Michalopoulos et al [1]. However, there is always scope for improvement with suggested areas for development including operator technique, appropriate image saving (radiographer training) and histological accuracy. In terms of complication rate, our centre compares favourably at <1%. In order to assess potential improvement, re-auditing should be carried out in 12 months time and results re-analysed.