Percutaneous (through the skin) liver biopsy is widely practiced in the evaluation of various acute and chronic liver disorders. Limitations of the current techniques are mainly related to the potential for bleeding complications with either of the conventional aspiration """"""""Menghini""""""""-style needle or cutting needles. Iii seriously ill patients, this necessitates either the performance of more invasive and expensive surgical or fluoroscopic transvenous biopsy techniques or treating the patient without the benefit of the biopsy which compromises therapeutic planning. In less acute situations, even minor bleeding from conventional biopsy may be the source of significant post-biopsy pain requiring extended post-procedure monitoring and analgesic medications. It is our HYPOTHESIS that withdrawal of the current biopsy needle from the liver causes minor bleeding of the tissue which results in pain and discomfort to the patient and additional hospitalization costs. The OBJECTIVE of this proposal is design and manufacture a functional prototype percutaneous biopsy needle capable of obtaining a quality core of tissue for diagnosis and automatically delivering a hemostatic plug into the biopsy tract. Our ultimate goal (Phase II) is to construct an inexpensive device which will provide a safer and less painful biopsy in the routine outpatient or bedside setting and a less invasive percutaneous biopsy in the setting of acute liver dysfunction. Use of the aspiration technique will allow a longer core than the cutting needle which is limited by the length of the specimen trough thus sometimes requiring more than one biopsy pass to obtain satisfactory amounts of tissue. Full automation of the method will enhance safety by decreasing the complexity of the procedure.
It is conservatively estimated that over 30,000 liver biopsies are performed annually in the United States. This number excludes those patients who are too ill to undergo the procedure, but many of whom may be eligible with hemostatic plugging, with a high risk/benefit ratio. With the successful development of this biopsy needle the risk/benefit ratio would change to favor the increased usage of the device as well as gaining a respectable share of the current market and reducing patient care costs.
