Conventional 15 G needle technique for renal biopsy compared with ultrasound-guided spring-loaded 18 G needle biopsy.

Two techniques for percutaneous renal biopsy were retrospectively reviewed to assess their relative safety and efficacy. Ultrasound localization of the kidney by a radiologists, with subsequent biopsy performed by a renal physician using a hand-held 15 G cutting needle (Tru-Cut), was compared with biopsy performed by a radiologist using an 18 G cutting needle with a spring-loaded biopsy device (Biopty) and real-time ultrasound guidance. The smaller needle with real-time ultrasound is more reliable at retrieving an adequate specimen for histological examination (93%) than the "conventional" technique (79%). Fewer complications occurred in the Biopty group although the difference did not reach statistical significance. The average length of stay in hospital was significantly shorter for elective biopsies with the Biopty device (1.80 compared with 2.93 nights, p less than 0.01). We recommend the use of the Biopty device with an 18 G needle and real-time ultrasound guidance as the method of choice for percutaneous renal biopsy.