Electrocautery of the tract after needle biopsy of the liver to reduce blood loss. Experience in the canine model

Feasibility and safety of bipolar radiofrequency track cautery during percutaneous image-guided abdominal biopsy procedures

PURPOSE

The purpose of this study was to assess the feasibility and safety of using a bipolar radiofrequency track cautery device during percutaneous image-guided abdominal biopsy procedures in at-risk patients.

METHODS

Forty-two patients (26-79 years old; female 44%) with at least one bleeding risk factor who underwent an abdominal image-guided (CT or US) biopsy and intended bipolar radiofrequency track cautery (BRTC) were retrospectively studied. An 18G radiofrequency electrode was inserted through a 17G biopsy introducer needle immediately following coaxial 18G core biopsy, to cauterize the biopsy track using temperature control. Bleeding risk factors, technical success, and adverse events were recorded.

RESULTS

BRTC was technically successful in 41/42 (98%) of procedures; in one patient, the introducer needle retracted from the liver due to respiratory motion prior to BRTC. BRTC following percutaneous biopsy was applied during 41 abdominal biopsy procedures (renal mass = 12, renal parenchyma = 10, liver mass = 9, liver parenchyma = 5, splenic mass or parenchyma = 4, gastrohepatic mass = 1). All patients had one or more of the following risk factors: high-risk organ (spleen or renal parenchyma), hypervascular mass, elevated prothrombin time, renal insufficiency, thrombocytopenia, recent anticoagulation or anticoagulation not withheld for recommended interval, cirrhosis, intraprocedural hypertension, brisk back bleeding observed from the introducer needle, or subcapsular tumor location. No severe adverse events (grade 3 or higher) occurred. Two (2/41, 5%) mild (grade 1) bleeding events did not cause symptoms or require intervention.

CONCLUSION

Bipolar radiofrequency track cautery was feasible and safe during percutaneous image-guided abdominal biopsy procedures. IRB approval: MBG 2022P002277.

Laser-heated needle for biopsy tract ablation: In vivo study of rabbit liver biopsy

PURPOSE

To investigate the efficacy of a newly-developed laser-heated core biopsy needle in the thermal ablation of biopsy tract to reduce hemorrhage after biopsy using in vivo rabbit's liver model.

MATERIALS AND METHODS

Five male New Zealand White rabbits weighed between 1.5 and 4.0 kg were anesthetized and their livers were exposed. 18 liver biopsies were performed under control group (without tract ablation, n = 9) and study group (with tract ablation, n = 9) settings. The needle insertion depth (~3 cm) and rate of retraction (~3 mm/s) were fixed in all the experiments. For tract ablation, three different needle temperatures (100, 120 and 150 °C) were compared. The blood loss at each biopsy site was measured by weighing the gauze pads before and after blood absorption. The rabbits were euthanized immediately and the liver specimens were stained with hematoxylin-eosin (H&E) for further histopathological examination (HPE).

RESULTS

The average blood loss in the study group was reduced significantly (p < 0.05) compared to the control group. The highest percentage of bleeding reduction was observed at the needle temperature of 150 °C (93.8%), followed by 120 °C (85.8%) and 100 °C (84.2%). The HPE results show that the laser-heated core biopsy needle was able to cause lateral coagulative necrosis up to 14 mm diameter along the ablation tract.

CONCLUSION

The laser-heated core biopsy needle reduced hemorrhage up to 93.8% and induced homogenous coagulative necrosis along the ablation tract in the rabbits' livers. This could potentially reduce the risk of tumor seeding in clinical settings.

Role of interventional radiology in managing pediatric liver tumors : Part 2: percutaneous interventions

Hepatoblastoma and hepatocellular carcinoma (HCC) are the most common pediatric liver malignancies, with hepatoblastoma occurring more commonly in younger children and HCC occurring more commonly in older children and adolescents. Although surgical resection (including transplant when necessary) and systemic chemotherapy have improved overall survival rate for hepatoblastoma to approximately 80% from 30%, a number of children with this tumor type are not eligible for operative treatment. In contradistinction, pediatric HCC continues to carry a dismal prognosis with an overall 5-year survival rate of 30%. The Paediatric Hepatic International Tumour Trial (PHITT) is an international trial aimed at evaluating both existing and emerging oncologic therapies for primary pediatric liver tumors. Interventional radiology offers a number of minimally invasive procedures that aid in diagnosis and therapy of pediatric liver tumors. For diagnosis, the PHITT biopsy guidelines emphasize and recommend percutaneous image-guided tumor biopsy. Additionally, both percutaneous and endovascular procedures provide therapeutic alternatives that have been, to this point, only minimally utilized in the pediatric population. Specifically, percutaneous ablation offers a number of cytotoxic technologies that can potentially eradicate disease or downstage children with unresectable disease. Percutaneous portal vein embolization is an additional minimally invasive procedure that might be useful to induce remnant liver hypertrophy prior to extended liver resection in the setting of a primary liver tumor. PHITT offers an opportunity to collect data from children treated with these emerging therapeutic options across the world. The purpose of this manuscript is to describe the potential role of minimally invasive percutaneous transhepatic procedures, as well as review the existing data largely stemming from the adult HCC experience.

A biopsy tool with integrated piezoceramic elements for needle tract cauterization and cauterization monitoring

This paper reports the feasibility of biopsy needle tract cauterization and cauterization monitoring using an embedded array of piezoceramic microheaters. Circular heaters of lead zirconate titanate (PZT-5A), with 200 μm diameter and 70-80 μm thickness, are fabricated using a batch mode micro ultrasonic machining process. These are then assembled into cavities in the walls of 20-gauge stainless steel needles and sealed with epoxy. Experiments are performed by inserting the proposed biopsy needle into porcine tissue samples. The needle surface exceeds the minimum target temperature rise of 33°C for either radial or thickness mode vibrations. The corresponding input power levels are 236 mW and 325 mW, respectively. The tissue cauterization extends 1-1.25 mm beyond the perimeter of the needle and is uniform in all directions. After cauterization, the fundamental anti-resonance frequency and the corresponding impedance magnitude of the PZT heater decrease by 4.1% and 42.6%, respectively, thereby providing a method to monitor the extent of tissue cauterization. A sensing interface circuit capable of measuring the resonance frequency shift of the PZT elements is built and tested using discrete integrated circuit components. The circuit detects the resonance frequency shift from 8.22 MHz to 7.96 MHz of the PZT elements when the biopsy needle is inserted into wax medium. An interface circuit for actuation of the PZT elements for tissue cauterization is also described.

Biopsy of the transplanted kidney

This article describes the current state-of-the-art technique of percutaneous transplant renal biopsy. A brief overview of the history of transplant renal biopsy is given. The indications and contraindications are discussed, including pre- and postprocedure patient management. The technique of the procedure and the devices that are available in the market are described.

A trucut biopsy needle for bipolar radiofrequency ablation of needle tract: a proof-of-concept experiment

OBJECTIVE

To develop a trucut biopsy needle featuring two electrodes that allow for bipolar radiofrequency (RF) coagulation of the puncture tract.

METHODS

We modified a 14-G trucut biopsy needle to contain two insulated electrodes and connected the device to an RF generator. Biopsies in ex vivo porcine liver and kidney were performed. The puncture tract was coagulated by using different RF energy settings (5 W, 10 W, 20 W). Tissue specimens were dissected along the puncture tract and the coagulation area was macroscopically evaluated. CT-guided in vivo liver and kidney biopsies were performed in two domestic pigs. Lengths of specimens were measured. Post-biopsy contrast-enhanced CT examinations were performed to rule out biopsy-related bleeding. Animals were euthanised and coagulation areas macroscopically explored.

RESULTS

The mean diameters of the coagulated area around the ex vivo biopsy tract were 4.2 +/- 1.1 mm (5 W), 6.0 +/- 2.0 mm (10 W) and 5.2 +/- 0.51 mm (20 W) in liver and 5.0 +/- 0.7 mm (5 W), 6.6 +/- 0.9 (10 W) and 6.0 +/- 2.0 mm (20 W) in kidney. After biopsies CT revealed no bleeding. Mean maximum coagulation diameters were 10.1 +/- 4.6 mm (10 W) in liver and 6.0 +/- 2.5 mm (10 W) in kidney. Mean length of the specimens was 12.2 +/- 4.4 mm in kidney and 11.1 +/- 3.6 mm in liver tissue.

CONCLUSION

Bipolar RF biopsy is a promising tool for tract coagulation after percutaneous biopsy.

Postbiopsy splenic bleeding in a dog model: comparison of cauterization, embolization, and plugging of the needle tract

OBJECTIVE

The purpose of our study was to compare radiofrequency cauterization, embolization using an absorbable gelatin sponge, and a Histoacryl-Lipiodol mixture plugging as postbiopsy bleeding reduction methods after splenic core needle biopsy in a dog model.

MATERIALS AND METHODS

Eleven mongrel dogs were randomly separated into nonheparinized (n = 5) and heparinized (n = 6) groups. Eight splenic biopsies per animal were performed using an 18-gauge automated core biopsy needle: two as controls, two ablated by radiofrequency, two embolized using an absorbable gelatin sponge, and two plugged using a Histoacryl-Lipiodol mixture. Procedure times and postbiopsy bleeding amounts were assessed. Statistically significant differences were determined by repeated measures analysis of variance; the Tukey-Kramer test for multiple comparisons was used for post hoc comparisons. Three-day follow-up CT scans were obtained to check for procedure-related complications or delayed bleeding.

RESULTS

The postbiopsy bleeding reduction groups showed significantly less blood loss than the control group for both the nonheparinized (p < 0.0001) and heparinized groups (p < 0.0001). In the heparinized group, both radiofrequency cauterization (p < 0.01) and gelatin sponge embolization (p < 0.05) significantly reduced bleeding compared with Histoacryl-Lipiodol mixture plugging. Gelatin sponge embolization was the longest procedure (p < 0.001). On follow-up CT, no delayed bleeding was observed. However, multiple Histoacryl-Lipiodol emboli were observed in the splenic and portal veins in all the dogs we treated.

CONCLUSION

Radiofrequency cauterization was found to be the most useful postbiopsy bleeding reduction method in terms of the amount of bleeding and the procedure time.

A feasibility study of high intensity focused ultrasound for liver biopsy hemostasis

This study was conducted to demonstrate the feasibility of high intensity focused ultrasound (HIFU) application to control post-liver-biopsy hemorrhage. Anesthetized Yorkshire pigs (n = 3; mean weight = 23.0 kg) were used and the liver organ was exposed surgically by an open laparotomy. Core biopsies were performed on the hepatic parenchyma with 14-gauge (n = 41) and 18-gauge (n = 33) core biopsy needles. The focus of HIFU (4.23 MHz) field was applied for 15 to 45 s to the needle entry site in the liver immediately after needle retraction. Blood loss from a biopsy site was determined using surgical sponges as absorbent applied at the site. Mean blood loss for control sites was 6.16 g (14-gauge, n = 20) and 1.22 g (18-gauge, n = 10). Virtually no blood loss was measured for biopsies after HIFU application (n = 44) for using needles of both sizes. Our results indicate that intraoperative HIFU application could successfully induce hemostasis after liver biopsy in a porcine model.

Radiofrequency Cauterization with Biopsy Introducer Needle

PURPOSE

The principal risks of needle biopsy are hemorrhage and implantation of tumor cells in the needle tract. This study compared hemorrhage after liver and kidney biopsy with and without radiofrequency (RF) ablation of the needle tract.

MATERIALS AND METHODS

Biopsies of liver and kidney were performed in swine through introducer needles modified to allow RF ablation with the distal 2 cm of the needle. After each biopsy, randomization determined whether the site was to undergo RF ablation during withdrawal of the introducer needle. Temperature was measured with a thermistor stylet near the needle tip, with a target temperature of 70 degrees C-100 degrees C with RF ablation. Blood loss was measured as grams of blood absorbed in gauze at the puncture site for 2 minutes after needle withdrawal. Selected specimens were cut for gross examination.

RESULTS

RF ablation reduced bleeding compared with absence of RF ablation in liver and kidney (P <.01), with mean blood loss reduced 63% and 97%, respectively. Mean amounts of blood loss (+/-SD) in the liver in the RF and no-RF groups were 2.03 g +/- 4.03 (CI, 0.53-3.54 g) and 5.50 g +/- 5.58 (CI, 3.33-7.66 g), respectively. Mean amounts of blood loss in the kidney in the RF and no-RF groups were 0.26 g +/- 0.32 (CI, -0.01 to 0.53 g) and 8.79 g +/- 7.72 (CI, 2.34-15.24 g), respectively. With RF ablation, thermal coagulation of the tissue surrounding the needle tract was observed.

CONCLUSION

RF ablation of needle biopsy tracts reduced hemorrhage after biopsy in the liver and kidney and may reduce complications of hemorrhage as well as implantation of tumor cells in the tract.

Postbiopsy bleeding in a porcine model: reduction with radio-frequency ablation--preliminary results

PURPOSE

To test a biopsy needle modified for use of radio-frequency (RF) energy to produce hemostasis after core biopsy of liver or kidney.

MATERIALS AND METHODS

RF energy was applied to a partially insulated 17-gauge needle, and tip temperature was monitored with a thermocouple. Domestic Yorkshire pigs (n = 4; mean weight, 23.4 kg) were anesthetized, and their livers and kidneys were exposed. Needles were inserted 2 cm into hepatic and renal parenchyma and retracted, either with or without tract ablation to 65 degrees C, in normal tissue, animals treated with anticoagulants, and an animal with acute inferior vena caval occlusion to produce portal hypertension. Blood loss was assessed by weighing surgical sponges with blood from the puncture sites. Significant differences in blood loss between control and ablated biopsy specimens in each scenario were tested by using a Wilcoxon matched-pairs signed rank test.

RESULTS

Mean blood loss for each group was as follows: In the liver, control biopsy specimens (n = 18) lost 0.30 g while ablated biopsy specimens lost 0.00044 g (P <.01), and control biopsy specimens treated with heparin (n = 26) lost 0.45 g while biopsy specimens treated with heparin and ablation lost 0.27 g (P =.03). For inferior vena caval occlusion, control biopsy specimens lost 1.23 g, while ablated biopsy specimens lost 0.00 g. In the kidney, control biopsy specimens (n = 28) lost 0.82 g, while ablated biopsy specimens lost 0.24 g (P =.01), and control biopsy specimens treated with heparin (n = 14) lost 1.04 g, while biopsy specimens treated with heparin and ablation lost 0.19 g (P =.02).

CONCLUSION

Tract ablation with thermocouple-monitored RF energy decreased postprocedural hemorrhage after hepatic and renal biopsy.

Use of fibrin sealant to reduce bleeding after needle liver biopsy in an anticoagulated canine model: work in progress

PURPOSE

Needle biopsy of the liver is a common diagnostic procedure. Although relatively safe, bleeding remains a potential complication and may occur more frequently in patients with coagulopathy. The purpose of this study was to evaluate the utility of a fibrin sealant in preventing bleeding after a 15-gauge needle biopsy of the liver in a canine model heparinized to simulate coagulopathy.

MATERIALS AND METHODS

Fibrin sealant was delivered to biopsy tract sites in eight dogs anticoagulated with heparin (activated clotting time 387 seconds +/- 94) using the same sheath system that was employed to obtain the biopsy specimen.

RESULTS

The results demonstrated complete hemostasis in the sealant-plugged tracts as compared to controls. Continuous bleeding was observed in none of the fibrin sealant-treated sites, compared with all of the control biopsy sites (P = .0078).

CONCLUSION

These results demonstrate the high degree of efficacy of fibrin sealant delivered through a sheath system in plugging liver biopsy tracts and eliminating bleeding in a severely coagulopathic animal model. This indicates that fibrin sealant use in cutting needle biopsies can reduce major and minor complications associated with the procedure.