High-intensity focused ultrasound ablation of liver tumors in difficult locations.

High-intensity focused ultrasound (HIFU) has been shown to be a valuable tool in the management of small liver tumors such as hepatocellular carcinoma (HCC). It has been shown to be a safe and effective means to ablate small HCC even in the presence of advanced cirrhosis. This review examines the challenges faced during HIFU ablation when the target tumors are located in difficult locations such as the liver dome, close to the rib cage, near large blood vessels or the heart, or adjacent to hollow viscera; and the special maneuvers employed to tackle such lesions.

Pilot study of high-intensity focused ultrasound ablation as a bridging therapy for hepatocellular carcinoma patients wait-listed for liver transplantation.

The objective of this study was to investigate the outcomes of high-intensity focused ultrasound (HIFU) ablation as a bridging therapy for patients with hepatocellular carcinoma (HCC) who had been wait-listed for deceased donor liver transplantation (DDLT). Adult patients with unresectable and unablatable HCCs within the University of California San Francisco criteria who had been wait-listed for DDLT were screened for their suitability for HIFU ablation as a bridging therapy if they were not suitable for transarterial chemoembolization (TACE). Treatment outcomes for patients receiving HIFU ablation, TACE, and best medical treatment (BMT) were compared. Fifty-one patients were included in the analysis. Before the introduction of HIFU ablation, only 39.2% of the patients had received bridging therapy (TACE only, n = 20). With HIFU ablation in use, the rate increased dramatically to 80.4% (TACE + HIFU, n = 41). The overall dropout rate was 51% (n = 26). Patients in the BMT group had a significantly higher dropout rate (P = 0.03) and significantly poorer liver function as reflected by higher Model for End-Stage Liver Disease scores and higher Child-Pugh grading. Clinically relevant ascites was found in 5 patients in the HIFU group and 2 patients in the BMT group, but none was found in the TACE group (P = 0.01 and P = 0.03, respectively). The TACE and HIFU groups had comparable percentages of tumor necrosis in excised livers (P = 0.35), and both were significantly higher than that in the BMT group (P = 0.01 and P = 0.02, respectively). In conclusion, HIFU ablation was safe even for HCC patients with Child-Pugh C disease. Its adoption increased the percentage of patients receiving bridging therapy from 39.2% to 80.4%. A randomized controlled trial for further validation of its efficacy is warranted.

Survival analysis of high-intensity focused ultrasound therapy vs. transarterial chemoembolization for unresectable hepatocellular carcinomas.

BACKGROUND & AIMS: High-intensity focused ultrasound (HIFU) ablation is a non-invasive treatment for unresectable hepatocellular carcinomas (HCCs), but long-term survival analysis is lacking. This study was to analyse its outcome compared to that of transarterial chemoembolization (TACE). METHODS: From October 2003 to September 2010, 113 patients received HIFU ablation as a treatment of HCCs at our hospital. Twenty-six patients had HCCs sized 3-8 cm. Fifty-two patients with matched tumour characteristics having TACE as primary treatment were selected for comparison. Short-term outcome and long-term survival were analysed. RESULTS: In the HIFU group (n = 26), 46 tumours were ablated. The median age of the patients was 69 (49-84) years. The median tumour size was 4.2 (3-8) cm. In the TACE group (n = 52), the median age of the patients was 67 (44-84) years. The median tumour size was 4.8 (3-8) cm. There was no hospital mortality in any of the groups. In the HIFU group, the rates of complete tumour response, partial tumour response, stable disease and progressive disease were 50%, 7.7%, 25.6% and 7.7% respectively, according to the modified Response Evaluation Criteria in Solid Tumours. The TACE group had the corresponding rates at 0%, 21.2%, 63.5% and 15.4% respectively (P < 0.0001). The 1-year, 3-year and 5-year survival rates were 84.6%, 49.2% and 32.3% respectively, in the HIFU group and 69.2%, 29.8% and 2.3% respectively, in the TACE group (P = 0.001). CONCLUSION: HIFU ablation is a safe and effective method for unresectable HCCs. A survival benefit is observed over sole TACE.

Survival analysis of high-intensity focused ultrasound ablation in patients with small hepatocellular carcinoma.

BACKGROUND: High-intensity focused ultrasound (HIFU) ablation is a non-invasive treatment for hepatocellular carcinoma (HCC). At present, data on the treatment's long-term outcome are limited. This study analysed the survival outcome of HIFU ablation for HCCs smaller than 3 cm. PATIENTS AND METHODS: Forty-seven patients with HCCs smaller than 3 cm received HIFU treatment between October 2006 and September 2010. Fifty-nine patients who received percutaneous radiofrequency ablation (RFA) were selected for comparison. The two groups of patients were compared in terms of pre-operative variables and survival. RESULTS: More patients in the HIFU group patients had Child-Pugh B cirrhosis (34% versus 8.5%; P = 0.001). The 1- and 3-year overall survival rates of patients whose tumours were completely ablated in the HIFU group compared with the RFA group were 97.4% versus 94.6% and 81.2% versus 79.8%, respectively (P = 0.530). The corresponding 1- and 3-year disease-free survival rates were 63.6% versus 62.4% and 25.9% versus 34.1% (P = 0.683). CONCLUSIONS: HIFU ablation is a safe and effective method for small HCCs. It can achieve survival outcomes comparable to those of percutaneous RFA and thus serves as a good alternative ablation treatment for patients with cirrhosis.

Tolerance of high-intensity focused ultrasound ablation in patients with hepatocellular carcinoma.

BACKGROUND: High-intensity focused ultrasound (HIFU) ablation is a relatively new, noninvasive way of ablation for treating hepatocellular carcinoma (HCC). Emerging evidence has shown that it is effective for the treatment of HCC, even in patients with poor liver function. There is currently no data on the safety limit of HIFU ablation in patients with cirrhosis. However, this information is vital for the selection of appropriate patients for the procedure. We analyzed HCC patients who had undergone HIFU ablation and determined the lower limit of liver function and other patient factors with which HCC patients can tolerate this treatment modality. METHODS: Preoperative variables of 100 patients who underwent HIFU ablation for HCC were analyzed to identify the risk factors in HIFU intolerance in terms of stress-induced complications. Factors that may contribute to postablation complications were compared. RESULTS: Thirteen (13 %) patients developed a total of 18 complications. Morbidity was mainly due to skin and subcutaneous tissue injuries (n = 9). Five patients had first-degree skin burn, one had second-degree skin burn, and three had third-degree skin burn. Four complications were grade 3a in the Clavien classification and 14 were below this grade. Univariate analysis showed that age (p = 0.022) was the only independent factor in HIFU intolerance. CONCLUSIONS: HIFU ablation is generally well tolerated in HCC patients with cirrhosis. It is safe for Child-Pugh A and B patients and selected Child-Pugh C patients. With this new modality, HCC patients who were deemed unsalvageable by other surgical means in the past because of simultaneous Child-Pugh B or C disease now have a new hope.

High-intensity focused ultrasound for hepatocellular carcinoma: a single-center experience.

OBJECTIVE: This study aims to evaluate the outcome of patients with hepatocellular carcinoma (HCC) treated by high-intensity focused ultrasound (HIFU) in a single tertiary referral center. BACKGROUND: HIFU is the latest developed local ablation technique for unresectable HCC. The initial experience on its efficacy is promising, but the survival benefit of patients undergoing HIFU for HCC is poorly defined. METHODS: From October 2006 to December 2008, 49 patients received HIFU for unresectable HCC. Each patient underwent a single session of HIFU with a curative intent. Treatment efficacy and survival outcome were evaluated. Clinicopathologic factors affecting the primary technique effectiveness and overall survival rates were investigated by univariate analysis. RESULTS: The median size of the treated tumors was 2.2 cm, ranging from 0.9 to 8 cm. The majority of patients had single tumors (n = 41, 83.6%). Thirty-one patients (63.2%) had artificial right pleural effusion during HIFU treatment to reduce damage to the lung and diaphragm. The hospital mortality rate was 2% (n = 1) and the complication rate was 8.1% (n = 4). The primary technique effectiveness rate was 79.5% (39 of 49 patients). It increased from 66.6% in the initial series to 89.2% in the last 28 patients. Tumor size (≥3.0 cm) was the significant risk factor affecting the complete ablation rate. The 1- and 3-year overall survival rates were 87.7% and 62.4%, respectively. Child-Pugh liver function grading was the significant prognostic factor influencing the overall survival rate. CONCLUSIONS: HIFU is an effective treatment modality for unresectable HCC with a high technique effectiveness rate and favorable survival outcome.

CT angiography versus conventional digital angiography in preoperative assessment for Chinese living kidney donors.

BACKGROUND: Computed tomography (CT) angiography is used for preoperative evaluation of living kidney donors, but its correlation with intraoperative findings during the transplant operation remains unknown. METHODS: Between April 1997 and October 2008, 34 consecutive pairs of living kidney transplants were carried out. Conventional digital angiography was employed for the preoperative assessment in the first 19 pairs, and CT angiography in the subsequent 15 pairs. The radiological reports and operative findings during kidney harvest were carefully examined and compared. RESULTS: Among the 34 cases in our cohort, we found 9 early branching renal arteries (26.4%) and 6 double renal arteries (17%). Venous and ureteral anomalies were rare, with only 1 case (2.9%) of each. CT angiography offered excellent and equal accuracy (accuracy 100%) when compared with conventional digital angiography for renal arterial anatomy. CT angiography showed superior performance compared with conventional angiography in the domain of venous and collecting system anomalies (accuracy 100% vs. 94.7%, respectively). No contrast nephropathy or allergy was documented in our series. CONCLUSIONS: CT angiography showed excellent correlations with surgical findings in the Chinese population. It is associated with minimal risk of contrast nephropathy as well as lower cost and therefore should be adopted as the standard preoperative assessment of living kidney donors.

Development and validation of an imaging and clinical scoring system to predict early mortality in spontaneous ruptured hepatocellular carcinoma treated with transarterial embolization.

PURPOSE: To develop and validate a scoring system using a combination of imaging and clinical parameters to predict 30-day mortality in ruptured HCC (rHCC) patients after transarterial embolization (TAE). METHODS: 98 consecutive patients with rHCC who underwent abdominal CT and subsequent TAE between January 2007 and December 2016 were retrospectively reviewed. The CT scans were reviewed by two radiologists blinded to the patient outcome. Clinical parameters including serum bilirubin, albumin, INR, creatinine, and hemoglobin were recorded. Independent risk factors for 30-day mortality after TAE were identified using multivariate binary logistic regression, for development of a scoring system. The scoring system was then validated in 20 patients between January 2017 and May 2018. RESULTS: In the development cohort, bilobar tumor distribution (OR = 29.6), clinical parameters of bilirubin > 2.5 mg/dL (OR = 5.9), and albumin < 30 g/L (OR = 4.1) were independent predictors for 30-day mortality. A 6-point score was derived and yielded area-under-the-receiver-operating-characteristic-curve (AUC) of 0.904. A score ≥ 4 resulted in sensitivity of 80.5% and specificity of 91.2% for 30-day mortality. In the validation cohort, AUC for 30-day mortality was 0.939. A score ≥ 4 resulted in sensitivity of 81.2% and specificity of 88.9%. In both development and validation cohorts, the proposed scoring system was better than biochemical components of Child-Pugh score and serum bilirubin to predict 30-day mortality. CONCLUSION: Imaging and clinical parameters can be combined into a scoring system to accurately predict 30-day mortality after TAE in rHCC patients. The score may help identify and counsel high-risk patients.

Serial changes of computed tomographic peritoneogram in patients with symptomatic ultrafiltration failure complicating continuous ambulatory peritoneal dialysis.

INTRODUCTION: It is well-known that continuous ambulatory peritoneal dialysis (CAPD) is associated with complications. And some of these complications are well-demonstrated as abnormalities on computed tomographic peritoneogram (CTP). The objective of our study is to document the serial changes of these complications. METHODS: We retrospectively reviewed 125 patients treated with CAPD for end staged renal failure (ESRF) who had CTP conducted in our hospital between December 2006 and August 2015. A total of 164 (n = 164) CTPs were performed. Patients with only one CTP performed were excluded from our study. A retrospective review of 68 serial CTPs studies on 28 patients during the 9-year period was undertaken. We looked into the serial changes on CTP. RESULTS: Among the 28 patients who had serial imaging, 46.43% of patients were found to have retroperitoneal leakage; 92.31% of them showed resolution in subsequent serial CTP. 21.43% of patients had anterior abdominal wall leakage; none of them resolved in subsequent CTP. 14.29% of patients were found to have inguinal hernias; 75% of them showed interval progression in subsequent serial CTPs. CONCLUSION: Retroperitoneal leakage is a common complication in patients on CAPD and tends to resolve whereas other complications including anterior abdominal wall leakage and hernias are unlikely to resolve and may progress further.

Personnel dose reduction in 90Y microspheres liver-directed radioembolization: from interventional radiology suite to patient ward.

OBJECTIVE: To describe a method to reduce the external radiation exposure emitted from the patient after liver-directed radioembolization using 90Y glass microspheres, to quantitatively estimate the occupational dose of medical personnel providing patient care to the patient radioembolized with the use of the method and to discuss radiation exposure to patients who are adjacent if the patient radioembolized needs hospitalization. METHODS: A lead-lined blanket of lead equivalence of 0.5 mm was used to cover the patient abdomen immediately after the 90Y radioembolization procedure, in order to reduce the radiation emitted from the patient. The interventional radiologist used a rod-type puncture site compressor for haemostasis to avoid direct contact with possible residual radioactivity at the puncture site. Dose rates were measured at the interventional radiologist chest and hand positions during puncture site pressing for haemostasis with and without the use of the blanket. The measurement results were applied to estimate the occupational dose of colleagues performing patient care to the patient radioembolized. The exposure to patients adjacent in the ward was estimated if the patient radioembolized was hospitalized. RESULTS: The radiation exposures measured at the radiologist chest and hand positions have been significantly reduced with the lead-lined blanket in place. The radiologist, performing puncture site pressing at the end of radioembolization procedure, would receive an average hand dose of 1.95 µSv and body dose under his own lead apron of 0.30 µSv for an average 90Y microsphere radioactivity of 2.54 GBq. Other medical personnel, nurses and porters, would receive occupational doses corresponding to an hour of background radiation. If the patient radioembolized using 90Y needs hospitalization in a common ward, using the lead-lined blanket to cover the abdomen of the patient and keeping a distance of 2 m from the patient who is adjacent would reduce the exposure by 0.42% of dose limit for the general public. CONCLUSION: By placing a lead-lined blanket on the patient abdominal region after 90Y radioembolization, hospital staff receive minimal radiation exposure in order to comply with the radiation protection "as low as reasonably achievable" principle. There will be no increase in radiation level in ward if the patient radioembolized using 90Y needs to be hospitalized. Therefore, the patient radioembolized can be accommodated alternatively at a corner bed of a common ward if an isolation room with private toilet facility is not available. Advances in knowledge: To reduce exposure to personnel providing patient care to patients radioembolized using 90Y.

Retroperitoneal leakage as a cause of ultrafiltration failure.

We report 3 patients on continuous ambulatory peritoneal dialysis (CAPD) who developed reversible ultrafiltration failure secondary to retroperitoneal leakage. The patients presented with pulmonary edema and fluid overload following a sudden onset of ultrafiltration failure on maintenance CAPD. There was no localized edema, suggesting peritoneal leakage in the abdominal wall or the perineum. Radiological examination showed no migration of the Tenckhoff catheter. Leakage of dialysate into the retroperitoneal space was only revealed by computed tomographic (CT) peritoneography. These patients were then treated with intermittent peritoneal dialysis twice weekly. After repeated CT peritoneography showing complete resolution of the leakage, they successfully resumed CAPD treatment 2 months later, without ultrafiltration problems. Our finding suggests that retroperitoneal leakage could be one of the uncommon, yet reversible, causes of acute ultrafiltration failure that can be diagnosed with CT peritoneography.

Treating a recurrent uterine arteriovenous malformation with uterine artery embolization. A case report.

BACKGROUND: Uterine arteriovenous malformation is a rare condition. Uterine artery embolization offers the possibility of conservative management as opposed to the traditional hysterectomy. We report a case with recurrent uterine arteriovenous malformation confirmed by angiography and successfully treated with a second embolization procedure. CASE: A 33-year-old woman presented with heavy vaginal bleeding. The diagnosis of uterine arteriovenous malformation was suspected on Doppler ultrasonography and confirmed by angiography. The first embolization procedure was performed using polyvinyl alcohol and steel coils. Recurrence was diagnosed 1 year later with the same imaging techniques. The second embolization procedure was performed using histoacryl. The patient remained asymptomatic at 1-year of follow-up. CONCLUSION: Minimally invasive management is an option in recurrent uterine arteriovenous malformation.

Survival analysis of transarterial radioembolization with yttrium-90 for hepatocellular carcinoma patients with HBV infection.

INTRODUCTION: For patients with resectable hepatocellular carcinoma (HCC), hepatectomy remains one of the best treatment options to provide long-term survival. However, more than 50% of the patients have unresectable disease upon diagnosis even though there are no distant metastases. Transarterial chemoembolization (TACE) is a well-established treatment option that offers a palliative survival benefit for this group of patients. A better treatment for unresectable HCC has been sought after. There is some evidence that transarterial radioembolization (TARE) with the agent yttrium-90 produces encouraging outcomes, especially in patients with portal vein tumor thrombus. This study aims to analyze the outcomes of TARE at our center. METHODS: From August 2009 to April 2013, 16 patients underwent TARE at our center. Sixteen patients with similar tumor characteristics were selected to undergo TACE alone for comparison. A retrospective analysis of the prospectively collected data of the patients was conducted. Only patients with newly diagnosed primary tumors were included in this study. RESULTS: The median survival for patients having TARE was 19.9 versus 14.0 months in the TACE group (P=0.615). There was no difference in terms of tumor response according to the modified Response Evaluation Criteria in Solid Tumors (mRECIST) (P=0.632). The 1-, 2- and 3-year survival rates in the TARE group were 80.0%, 30.5% and 20.3% respectively. The 1-year survival in the TACE group was 58.3% (P=0.615). For patients who had major vascular invasion (eight in each group), the 1- and 2-year survival rates in the TARE group were 62.5% and 15.6% respectively, while the 1-year survival in the TACE group was 35.0% (P=0.664). CONCLUSIONS: The two groups showed similar results in terms of tumor response and overall survival benefit. TARE might provide a survival benefit for patients with major vessel invasion.

Embolisation of hypervascular bone tumours: a pictorial essay with literature review.

Bone tumours, either primary or secondary, can present in various debilitating manners, including pain and pathological fracture. The situation is particularly problematic when the tumours are hypervascular, and located in regions where a high risk of neurological compromise is anticipated during operation, such as in the spine or sacrum. In such situations, bone tumour embolisation is a useful and effective adjunctive treatment for reducing intra-operative blood loss. This is particularly relevant in primary bone tumours such as giant cell tumours and metastatic renal cell and thyroid tumours. With a proper pre-embolisation angiogram and knowledge of anatomy, careful selective cannulation of the arterial supplies and experience in using embolic agents, the risks of non-target embolisation can be kept to minimum and the best result achieved.

High-intensity focused ultrasound ablation: an effective bridging therapy for hepatocellular carcinoma patients.

AIM: To analyze whether high-intensity focused ultrasound (HIFU) ablation is an effective bridging therapy for patients with hepatocellular carcinoma (HCC). METHODS: From January 2007 to December 2010, 49 consecutive HCC patients were listed for liver transplantation (UCSF criteria). The median waiting time for transplantation was 9.5 mo. Twenty-nine patients received transarterial chemoembolization (TACE) as a bringing therapy and 16 patients received no treatment before transplantation. Five patients received HIFU ablation as a bridging therapy. Another five patients with the same tumor staging (within the UCSF criteria) who received HIFU ablation but not on the transplant list were included for comparison. Patients were comparable in terms of Child-Pugh and model for end-stage liver disease scores, tumor size and number, and cause of cirrhosis. RESULTS: The HIFU group and TACE group showed no difference in terms of tumor size and tumor number. One patient in the HIFU group and no patient in the TACE group had gross ascites. The median hospital stay was 1 d (range, 1-21 d) in the TACE group and two days (range, 1-9 d) in the HIFU group (P < 0.000). No HIFU-related complication occurred. In the HIFU group, nine patients (90%) had complete response and one patient (10%) had partial response to the treatment. In the TACE group, only one patient (3%) had response to the treatment while 14 patients (48%) had stable disease and 14 patients (48%) had progressive disease (P = 0.00). Seven patients in the TACE group and no patient in the HIFU group dropped out from the transplant waiting list (P = 0.559). CONCLUSION: HIFU ablation is safe and effective in the treatment of HCC for patients with advanced cirrhosis. It may reduce the drop-out rate of liver transplant candidate.

Results of percutaneous transhepatic cholecystostomy for high surgical risk patients with acute cholecystitis.

AIM: To assess the efficacy and safety of percutaneous transhepatic cholecystostomy (PTC) in treatment for acute cholecystitis in high surgical risk patients. PATIENTS AND METHODS: A retrospective review was carried out from January 1999 to June 2007 on 23 patients, 11 males and 12 females, who underwent PTC for the management of acute cholecystitis at the Department of Surgery, Queen Mary Hospital, Hong Kong, China. The mean age of the patients was 83. They all had either clinical or radiological evidence of acute cholecystitis and had significant pre-morbid diseases. The median follow-up period on them was 35 months. RESULTS: All the PTCs performed were technically successful. One patient died from procedure-related haemoperitoneum, while 87% (n = 20) of all the patients had clinical resolution of sepsis by 20 h after PTC. Eight patients underwent elective cholecystectomy afterwards (62.5% with the laparoscopic approach). Eight patients had dislodgement of the PTC catheter and one of them developed recurrent acute cholecystitis 3 months after PTC. That patient was treated conservatively. Four patients died from their pre-morbid conditions during the follow-up period. CONCLUSION: PTC was a safe and effective alternative for treating acute cholecystitis in this group of patients. Thirteen of them without elective cholecystectomy performed did not have recurrent acute cholecystitis after a single session of PTC. It may be considered as a definitive treatment for this group of patients.