Comparison of safety and accuracy of ultrasound-guided versus ultrasound-assisted biopsy with 18- or 16-gauge needle in diffuse liver diseases

Ultrasound (US) guide is commonly used for focal hepatic lesions but not for diffuse liver disease biopsy. We compared safety of procedure and adequacy of specimen for histologic evaluation of diffuse liver disease by using US-assisted 16 gauges (USA16) or US-guided 18 G (USG18) needle biopsies.

A prospective study was undertaken over one year period, from September 2006 to September 2007. USA16 needle biopsy was performed in 50 patients (M/F 30/20; median age 45y; range 28–72) (group A), instead USG18 needle biopsy was used in 40 patients (M/F 23/17; median age 50y; range 26–71) (group B). The most common indications for biopsy were viral hepatitis (58 patients) and elevated liver function tests of unknown cause (32 patients). US evaluation was performed after the procedure to exclude possible complications. 1 and 24 hours after the procedure patients were asked to grade their pain on a 1 to 10 scale (1=no pain). Main outcome measures were: number of complications, patient's tolerance and adequacy of specimens (number of portal spaces and length of the specimen).

In all patients, pain was the most common minor complication, occurring in 15 patients (37.5%) of group A and 39 patients (78%) of group B (p<0.05). The average score of pain at 1 and 24-hrs after the biopsy was 2.1±1 and 1.5±1 in Group A, and 4.8±2 and 3.1±1 in group B, respectively (p<0.05). After 24-hrs, all patients returned to normal activities except 1 (2.5%) of group A and 6 (12%) of group B (p<0.01), requiring prolonged hospital stay for persisting pain. Major complications were recorded only in 2 (4%) patients of group A (1 lypotimia and 1 subcutaneous haematoma). The specimens were diagnostic in all procedures. The average length of the specimen was greater with USG18 biopsies (2.8 + 0.9cm vs. 1.5+0.8cm; p<0.05), despite the use of smaller calibre needle; no significant difference in the number of portal spaces between two groups was found (13±3 vs. 15±3).

Our study demonstrates that both USA16 and USG18 needle liver biopsies provide adequate histological specimens for diagnosis of diffuse liver disease; moreover, although using a smaller calibre needle, USG18 biopsy provided longer specimens, decreasing the need of second pass and, furthermore, it is significantly more tolerated by the patients.