Percutaneous image-guided needle biopsy is typically performed in highly vascular organs or in tumours with rich macroscopic and microscopic blood supply. The main risks related to this procedure are haemorrhage and implantation of tumour cells in the needle tract after the biopsy needle is withdrawn. From numerous conducted studies, it was found that heating the needle tract using alternating current in radiofrequency (RF) range has a potential to minimize these effects. However, this solution requires the use of specially designed needles, which would make the procedure relatively expensive and complicated. Thus, we propose a simple solution by using readily available coaxial core biopsy needles connected to a radiofrequency ablation (RFA) generator. In order to do so, we have designed and developed an adapter to interface between these two devices. For evaluation purpose, we used a bovine liver as a sample tissue. The experimental procedure was done to study the effect of different parameter settings on the size of coagulation necrosis caused by the RF current heating on the subject. The delivery of the RF energy was varied by changing the values for delivered power, power delivery duration, and insertion depth. The results showed that the size of the coagulation necrosis is affected by all of the parameters tested. In general, the size of the region is enlarged with higher delivery of RF power, longer duration of power delivery, and shallower needle insertion and become relatively constant after a certain value. We also found that the solution proposed provides a low cost and practical way to minimizes unwanted post-biopsy effects.
OBJECTIVE: To compare the effectiveness of the Vabra aspirator and the Pipelle device as an outpatient endometrial assessment tool.
METHOD: This was a randomised, prospective trial conducted for a period of one year.
RESULTS: A total of 147 patients were recruited, of which 71 were in the Vabra group and 76 were in the Pipelle arm. The procedure success rate in the Pipelle group was significantly higher than the Vabra arm (98.7 vs 88.7%, P=0.02). Adequate tissue yield was also significantly more in the Pipelle arm (73.3 vs 52.4%, P=0.02). Cost-benefit analysis revealed a higher average cost per patient in the Vabra group compared to the Pipelle arm.
CONCLUSION: This study proved that the Vabra aspirator was not as effective as the Pipelle device in obtaining endometrial tissue for histological diagnosis. Despite its higher price per unit, the Pipelle device was a more cost-effective tool for outpatient endometrial assessment.
Study site: Medical clinic, Pusat Perubatan Universiti Kebangsaan Malaysia (PPUKM), Kuala Lumpur, Malaysia.