Kidney autotransplantation for the treatment of renal artery occlusion after endovascular aortic repair: a case report.

BACKGROUND: Unintentional renal artery occlusion after endovascular aneurysm repair (EVAR) for abdominal aortic aneurysm remains one of the most unfavorable complications. Renal salvage options include percutaneous transluminal renal artery angioplasty (PTRA) and open hepatosplenorenal bypass. However, the usefulness of kidney autotransplantation (AutoTx) remains unclear. CASE PRESENTATION: A 76-year-old woman with a right solitary kidney attributable to a left renal thromboembolism had previously undergone EVAR with a stent graft for an infrarenal aortic aneurysm, which led to ostial occlusion of the right renal artery. In addition, she had undergone PTRA and stenting. Two days before admission, she developed leg edema and hypertension, leading her to visit the hospital. Her serum creatinine level was 2.4 (baseline, 1.0) mg/dL. Acute kidney injury due to renal artery in-stent restenosis was suspected; re-angioplasty was attempted on day 2 of hospitalization, but was unsuccessful. Her renal function did not improve and anuria persisted; thus, hemodialysis was initiated on the same day. The right kidney size (8.6 cm) was preserved relative to her body size, with only mild cortical atrophy. Doppler ultrasonography and mercaptoacetyltriglycine scintigraphy revealed minimal but significant perfusion of the right kidney. Therefore, we considered that kidney perfusion was sustained and renal function could be reversed. On day 25 of hospitalization, right kidney AutoTx to the right iliac fossa was performed to reestablish adequate renal perfusion and reverse the need for dialysis. Soon after the procedure, the patient started passing urine. Her renal function improved; her serum creatinine level decreased to 1.0 mg/dL on day 33 of hospitalization. Hemodialysis was discontinued after the surgery. Zero-hour kidney biopsy showed only mild tubular injury, with neither tubular necrosis nor glomerular abnormalities. CONCLUSIONS: Kidney AutoTx can be performed for patients with renal artery in-stent occlusion after unsuccessful PTRA who previously underwent EVAR. Our case showed successful recovery of renal function nearly 1 month after renal artery occlusion, indicating that revascularization should be considered even if it is delayed, as the kidney might be perfused through collateral circulation.

Surgical outcomes of aortic repair via transapical cannulation and the adventitial inversion technique for acute Type A aortic dissection.

OBJECTIVES: To evaluate the surgical outcomes of aortic repair via transapical cannulation and the adventitial inversion technique for acute Type A aortic dissection. METHODS: Between 2008 and 2015, a total of 300 patients with acute Type A aortic dissection underwent emergency surgery, consisting of 271 hemiarch repairs and 29 total aortic arch replacements, using transapical cannulation and the adventitial inversion technique at a distal anastomosis. The mean follow-up periods were 31.7 ± 25.2 months. Overall, 18% (54/300) of the patients were octogenarians, and 21.7% (65/300) had cardiac tamponade; 25% (75/300) had preoperative malperfusion. RESULTS: The in-hospital and 30-day mortality rates were 8.3% (25/300) and 6.7% (20/300), respectively. The 30-day mortality rate was 2.7% (6/225) among patients without preoperative malperfusion and 18.7% (14/75) among patients with malperfusion (P < 0.0001), 7.4% (4/54) among octogenarians and 6.5% (16/246) among patients aged less than 80 years (P = 0.81), and 6.3% (17/271) among patients treated with hemiarch repair and 10.3% (3/29) among patients treated with total aortic arch replacement (P = 0.403). Preoperative malperfusion was an independent predictor of perioperative mortality in a multivariable analysis. During the follow-up period, distal reintervention was performed in 11% (33/300) of the patients. The rates of freedom from reintervention at 1, 3 and 5 years were 95.9%, 88.9% and 80.0%, respectively. The overall survival rates at 1, 3 and 5 years were 88.7%, 86.7% and 82.0%, respectively. The in-hospital mortality rate for elective reintervention was 3.0% (1/33). CONCLUSIONS: Aortic repair via transapical cannulation and the adventitial inversion technique for acute Type A aortic dissection provides good early and mid-term results. The safety of elective distal reintervention can be guaranteed. To obtain better operative outcomes, effective treatment for cases with malperfusion is mandatory.

Sac angiography and glue embolization in emergency endovascular aneurysm repair for ruptured abdominal aortic aneurysm.

PURPOSE: The purpose of this study was to demonstrate a sac angiography technique and evaluate the feasibility of N-butyl cyanoacrylate (NBCA) embolization of the ruptured abdominal aortic aneurysm (AAA) sac in emergency endovascular aneurysm repair (EVAR) in hemodynamically unstable patients. METHODS: A retrospective case series of three patients in whom sac angiography was performed during emergency EVAR for ruptured AAA was reviewed. After stent graft deployment, angiography within the sac of aneurysm (sac angiography) was performed by manually injecting 10 ml of contrast material through a catheter to identify the presence and site of active bleeding. In two patients, sac angiography revealed active extravasation of the contrast material, and NBCA embolization with a coaxial catheter system was performed to achieve prompt sealing. RESULTS: Sac angiography was successful in all three patients. In the two patients who underwent NBCA embolization for aneurysm sac bleeding, follow-up computed tomography (CT) images demonstrated the accumulation of NBCA consistent with the bleeding site in preprocedural CT images. CONCLUSIONS: EVAR is associated with a potential risk of ongoing bleeding from type II or IV endoleaks into the disrupted aneurysm sac in patients with severe coagulopathy. Therefore, sac angiography and NBCA embolization during emergency EVAR may represent a possible technical improvement in the treatment of ruptured AAA in hemodynamically unstable patients.

Dynamic volumetric CT angiography for the detection and classification of endoleaks: application of cine imaging using a 320-row CT scanner with 16-cm detectors.

PURPOSE: To assess the feasibility and diagnostic performance of dynamic volumetric computed tomography (CT) angiography with large-area detectors in the detection and classification of endoleaks after endovascular aneurysm repair (EVAR). MATERIALS AND METHODS: Low-dose dynamic volumetric CT angiography performed with the patient in Fowler position was used to scan the entire stent graft with a 16-cm-area detector during the first follow-up examination after EVAR. There were 39 consecutive patients (36 men and 3 women; mean age, 74 y ± 8.7) examined with approximately 14-20 intermittent scans (temporal resolution, 2 s; scan range, 160 mm). The effective radiation dose, image quality, interobserver and intraobserver agreement for endoleak detection, and time delay between peak enhancement of the aorta and endoleaks were evaluated. RESULTS: All examinations with the patient in Fowler position enabled the entire stent graft to be scanned and were rated as diagnostic. The mean effective radiation dose was 13.1 mSv. Endoleaks were detected in eight patients (type Ia, n = 1; type II, n = 6; type III, n = 1). Interobserver agreement (κ = 0.794) and intraobserver agreement (κ = 1.00) for detection of endoleaks were excellent. The mean time delay between peak enhancement of the aorta and the endoleaks was significantly less for type I/III endoleaks (2.0 s ± 0) compared with type II endoleaks (5.3 s ± 1.0; P < .001). CONCLUSIONS: Low-dose dynamic volumetric CT angiography performed with the patient in Fowler position is feasible after EVAR. Dynamic information, including cine imaging, the timing of peak enhancement, and the Hounsfield units index, is useful in detecting and classifying endoleaks.

Risk factors for systemic air embolism as a complication of percutaneous CT-guided lung biopsy: multicenter case-control study.

PURPOSE: To determine risk factors for systemic air embolism by percutaneous computed tomography (CT)-guided lung biopsy. METHODS: This case-control study used data from 2216 percutaneous lung biopsy procedures performed over 11 years at 12 institutions in Japan. Systemic air embolism was identified by retrospective review of CT images obtained during and immediately after the procedures. To fulfill our objective, multiple variables were compared between cases and controls with univariate analyses by using Student's t test and Fisher's exact test for numerical and categorical values, respectively. Multivariate logistic regression analysis was then performed using selected variables. RESULTS: Ten cases of systemic air embolism and 2,206 controls were identified. Univariate analyses showed that the lesions in the lower lobe (P = 0.025) and occurrence of parenchymal hemorrhage (P = 0.019) were significant risk factors. Multivariate analysis showed that the use of a larger biopsy needle was a significant risk factor (P = 0.014). CONCLUSION: Parenchymal hemorrhage during the procedure, lesions in the lower lobe, and the use of larger biopsy needles may be risk factors for systemic air embolism by percutaneous CT-guided lung biopsy. Our findings may provide clues toward minimizing the risk of this complication.

The upside down Endurant iliac limb stent graft for treatment of a common iliac artery aneurysm.

Endovascular repair of the coverage from the common iliac artery to the external iliac artery after the internal iliac artery embolization has been proven to be a safe and effective treatment in isolated iliac artery aneurysms. But in cases in which the diameter of the proximal sealing zone is larger than that of the distal sealing zone, a reverse-tapered device is needed. We described the off-label use of the Endurant iliac limb stent graft in an upside down configuration to accommodate this diameter mismatch.

Use of the Endurant stent graft system for ruptured infrarenal aortic aneurysms: short-term experience in nine patients.

PURPOSE: To report the early results of use of the Endurant stent graft in the treatment of ruptured abdominal aortic aneurysms (AAAs). MATERIALS AND METHODS: Nine consecutive patients (seven men and two women; mean age, 76 y; range, 65-87 y) underwent endovascular aneurysm repair (EVAR) for a ruptured AAA with the Endurant stent graft between April and December 2012. EVAR was emergent in all cases. Early technical success, clinical success, major complication, and mortality rates were analyzed. RESULTS: Intraoperative immediate technical success was achieved in all nine patients. The 30-day clinical success rate was 67% (six of nine patients). The 30-day mortality rate was 33% (three of nine patients). During a mean follow-up of 6 months (range, 3-10 mo), none of the cases required reintervention; there was one late death attributed to probable endograft infection. CONCLUSIONS: The short-term results of EVAR with the Endurant stent graft in patients with ruptured AAAs are encouraging.

Endometrial polyps: MR imaging features.

The purpose of this study is to evaluate the diagnostic usefulness of magnetic resonance imaging (MRI) characteristics of endometrial polyps in order to differentiate them from other endometrial lesions. MRI was retrospectively reviewed in 40 patients with pathologically proven endometrial polyps. Special attention was paid to the sizes, shapes, margins, internal structures, signal intensities, and post-contrast enhancement patterns. A central fibrous core, intratumoral cysts, and hemorrhage were seen in 30 (75%), 22 (55%), and 14 (35%) patients, respectively. The predominant signal intensity of the lesions showed iso-to slightly low signal intensity relative to the endometrium on T2-weighted images in 36 (90%), low signal intensity on diffusion-weighted images in 32 (80%), and strong or moderate enhancement on enhanced T1-weighted images in 28 patients (70%), respectively. In 32 (80%) patients, the endometrial polyps showed global or partial early enhancement. On dynamic study, rapid enhancement with a persistent strong enhancement pattern was seen in 17 (42.5%) and a gradually increasing enhancement pattern was seen in 17 patients (42.5%). These MRI features can be helpful to distinguish the endometrial polyps from various other endometrial lesions.

Measurement of pleural temperature during radiofrequency ablation of lung tumors to investigate its relationship to occurrence of pneumothorax or pleural effusion.

The purpose of this study was to investigate the relationship between pleural temperature and pneumothorax or pleural effusion after radiofrequency (RF) ablation of lung tumors. The pleural temperature was measured immediately outside the lung surface nearest to the tumor with a fiber-type thermocouple during 25 ablation procedures for 34 tumors in 22 patients. The procedures were divided into two groups depending on the highest pleural temperature: P-group I and P-group II, with highest pleural temperatures of <40 degrees C and >/=40 degrees C, respectively. The incidence of pneumothorax or pleural effusion was compared between the groups. Multiple variables were compared between the groups to determine the factors that affect the pleural temperature. The overall incidence of pneumothorax and pleural effusion was 56% (14/25) and 20% (5/25), respectively. Temperature data in five ablation procedures were excluded from the analyses because these were affected by the pneumothorax. P-group I and P-group II comprised 10 procedures and 10 procedures, respectively. The incidence of pleural effusion was significantly higher in P-group II (4/10) than in P-group I (0/10) (p = 0.043). However, the incidence of pneumothorax did not differ significantly (p = 0.50) between P-group I (4/10) and P-group II (5/10). Factors significantly affecting the pleural temperature were distance between the electrode and the pleura (p < 0.001) and length of the lung parenchyma between the electrode and the pleura (p < 0.001). We conclude that higher pleural temperature appeared to be associated with the occurrence of pleural effusion and not with that of pneumothorax.

Radiofrequency ablation followed by radiation therapy for large primary lung tumors.

We report the clinical experience of radiofrequency ablation followed by radiation therapy for large primary lung tumors. Two patients with large primary lung tumors were treated with combined radiofrequency ablation and radiation therapy, and good local control was observed. Combined radiofrequency ablation and radiation therapy that involves minimally invasive techniques appears to be promising for the treatment of large lung tumors.

Transhepatic approach for percutaneous computed-tomography-guided radiofrequency ablation of renal cell carcinoma.

We performed percutaneously radiofrequency (RF) ablation of 5 renal cell carcinomas (mean diameter 26 +/- 15 mm) with computed-tomography (CT) fluoroscopic guidance using the transhepatic route. The RF electrode was successfully advanced into all tumors. RF ablation caused one minor complication (small asymptomatic perirenal hematoma); no major complications occurred. The follow-up contrast-enhanced CT images showed no local tumor progression of any tumors in a median period of 10 months (range 3-14 months). In conclusion, it seems that this transhepatic approach is safe and can be an alternative method for electrode insertion during RF ablation of selected renal tumors.

Radiofrequency ablation for the treatment of unresectable lung metastases in patients with colorectal cancer: a multicenter study in Japan.

PURPOSE: Results after lung radiofrequency (RF) ablation were retrospectively evaluated to determine whether lung RF ablation is an effective therapeutic option for the treatment of unresectable lung metastases from colorectal cancer. MATERIALS AND METHODS: Seventy-one patients with 155 unresectable colorectal lung metastases underwent computed tomography (CT)-guided percutaneous RF ablation at four institutions. The maximum tumor size was 3 cm or less in 61 patients and 3.1-6.0 cm in 10 patients (range, 0.5-6.0 cm; mean, 2.4 cm +/- 1.3). A single tumor was treated in 35 patients and multiple tumors in 36 patients. Extrapulmonary metastases were found in 30 patients. Follow-up with serial CT and positron emission tomography scans was performed from 4 to 42 months after RF ablation (mean, 19 months). Primary end point in this study was patient survival, and secondary end points were evaluation of safety of lung RF ablation and intrapulmonary recurrence. RESULTS: Pneumothorax developed in 26 (37%) patients, and a chest tube was placed in 14 (20%) of them. Empyema developed in one (1%) patient. Thirty-three (47%) patients developed intrapulmonary recurrence and 19 (58%, 19/33) of them received repeat lung RF ablation. The estimated 3-year survival rate was 46% for all patients. Extrapulmonary metastasis, tumor size, and the carcinoembryonic antigen level were significant prognostic factors in the univariate analysis. The first two factors were significantly independent prognostic factors in the multivariate analysis. Thirty-six patients with small lung metastases (< or =3 cm) and no extrapulmonary metastases had a 3-year survival rate of 78%. CONCLUSIONS: Lung RF ablation is a safe and effective treatment in selected patients with unresectable lung metastases from colorectal cancer.

Intractable pneumothorax due to bronchopleural fistula after radiofrequency ablation of lung tumors.

We describe two cases of intractable pneumothorax that were attributed to a bronchopleural fistula (BPF) after radiofrequency ablation of lung tumors. In both cases, radiofrequency ablation induced necrosis of the lung tissue between the pleural space and the bronchus. The bronchopleural fistula formed after sloughing of the necrotic tissue. Management of the bronchopleural fistula was quite challenging, requiring frequent treatments, including pleurodesis, endobronchial management, and/or surgical repair. In one of the patients, air leakage persisted despite these efforts, and the patient died of acute pneumonia 52 days after the procedure. Although it is rare, with an incidence of 0.6% (2/334) at our institution, intractable pneumothorax due to bronchopleural fistula should be recognized as a risk associated with radiofrequency ablation of lung tumors.

Feasibility of percutaneous radiofrequency ablation for intrathoracic malignancies: a large single-center experience.

BACKGROUND: Radiofrequency ablation (RFA) has become an accepted alternative for treating intrathoracic malignancies; however, the incidence and characteristics of peri- and postprocedural complications are not well described. The purpose of the study was to assess the safety and technical feasibility of percutaneous RFA in unresectable intrathoracic malignancies. METHODS: Percutaneous RFA was performed in patients with intrathoracic malignancies between June 2001 and December 2004. In total, 366 tumors were treated in 137 patients in 211 sessions. All patients were nonsurgical candidates or had refused surgery. Three hundred and thirty-six lesions were subjected to RFA for the treatment of metastases and 30 lesions for primary lung carcinoma. RESULTS: Although no procedural mortality occurred, 2 patients died during the course of the study because of intractable pneumothorax and massive hemoptysis (0.9%). The overall major complication rate was 17.1% (pneumothoraces requiring tube drainage in 25, pleuritis in 6, pleural effusion requiring tube drainage in 4, lung abscess in 1, and intrapulmonary hemorrhage with hemothorax in 1). Minor complications included pneumothoraces not requiring tube drainage in 108 sessions, pleural effusion without drainage in 34, hemosputum in 9, nausea and/or vomiting in 3, subcutaneous emphysema in 3, cough in 2, skin burn in 2, atelectasis in 1, and subileus in 1. High fever and/or chest pain were seen in 33.8% and 39.3% of patients, respectively. CONCLUSIONS: With over 200 procedures, RFA appears to be a safe and minimally invasive option with negligible mortality and little morbidity in selected patients with unresectable intrathoracic malignancies.

Radiofrequency ablation of normal lungs after pulmonary artery embolization with use of degradable starch microspheres: results in a porcine model.

PURPOSE: The present study was performed to evaluate the effect of pulmonary artery embolization on radiofrequency (RF) ablation of normal porcine lungs. MATERIALS AND METHODS: RF ablation zones (n=34) were created in the normal lungs of five domestic pigs (five zones in each of the first two pigs and eight zones in each of the remaining three pigs) with an expandable multitined electrode with use of bilateral thoracotomy. RF ablation was performed without pulmonary artery embolization (group 1, n=8), immediately after embolization (group 2, n=11), 15 minutes after embolization (group 3, n=7), and 30 minutes after embolization (group 4, n=8) with degradable starch microspheres. Among them, 12 ablation zones were excluded from this study because they were considerably limited by the presence of the pleura or large bronchi. The remaining 22 zones were included (n=7, n=5, n=4, and n=6 in groups 1, 2, 3, and 4, respectively). Coagulation necrosis volumes in the ablation zones were measured and compared among the groups. RESULTS: Coagulation necrosis volumes were 0.9+/-0.5 cm3, 2.1+/-0.4 cm3, 2.1+/-1.0 cm3, and 1.9+/-0.6 cm3 in groups 1, 2, 3, and 4, respectively. Groups 2-4 showed significantly larger coagulation volumes than group 1 (P=.012, P=.023, and P=.010 in groups 2, 3, and 4, respectively). CONCLUSION: Pulmonary artery embolization contributed to larger volumes of coagulation necrosis after RF ablation of normal lungs.

Risk factors for local progression after percutaneous radiofrequency ablation of lung tumors: evaluation based on a preliminary review of 342 tumors.

BACKGROUND: The purpose of the study was to retrospectively evaluate the risk factors for local progression after percutaneous radiofrequency (RF) ablation of lung tumors. METHODS: The study included 128 patients (77 men, 51 women; mean age, 61.3 years) with 342 tumors (25 primary and 317 metastatic lung neoplasms; mean long-axis diameter, 1.7 cm) treated with RF ablation. The overall primary and secondary technique effectiveness rates were estimated using Kaplan-Meier analysis. Multiple variables were analyzed using the log-rank test, followed by multivariate multilevel analysis to determine independent risk factors for local progression. The primary and secondary technique effectiveness rates were again estimated when considering only tumors without independent risk factors. RESULTS: The median follow-up period was 12 months (range, 6-47 months). The overall primary and secondary technique effectiveness rates were 72% and 84% at 1 year, 60% and 71% at 2 years, and 58% and 66% at 3 years, respectively. Larger tumor size (hazard ratio [HR], 1.97; 95% confidence interval [95% CI], 1.47-2.65; P < .00001) and the use of an internally cooled electrode (HR, 2.32; 95% CI, 1.10-4.90; P = .027) were assessed as independent risk factors for local progression. The primary and secondary technique effectiveness rates when considering tumors smaller than 2 cm and treated with a multitined expandable electrode were 89% and 89% at 1 year and 66% and 78% at 2 years, respectively. CONCLUSIONS: Larger tumor size and the use of an internally cooled electrode were independent risk factors for local progression after RF ablation of lung tumors.

Pneumothorax, pleural effusion, and chest tube placement after radiofrequency ablation of lung tumors: incidence and risk factors.

PURPOSE: To retrospectively evaluate the incidence of and risk factors for pneumothorax, pleural effusion, and chest tube placement for pneumothorax after radiofrequency (RF) ablation of lung tumors. MATERIALS AND METHODS: Institutional review board approval was obtained, with waiver of informed consent. This retrospective study comprised 224 ablation sessions for 392 tumors in 142 patients (92 men, 50 women; mean age, 64.0 years). Multiple variables were analyzed by using the Student t test or the Mann-Whitney U test for numerical values and by using the chi(2) test or the Fisher exact test for categorical values in order to assess risk factors for pneumothorax, pleural effusion, and chest tube placement for pneumothorax. RESULTS: The incidence of pneumothorax, pleural effusion, and chest tube placement for pneumothorax was 52% (117 of 224 sessions), 19% (42 of 224 sessions), and 21% (24 of 117 sessions), respectively. For pneumothorax, risk factors included male sex (P = .030), no history of pulmonary surgery (P < .001), a greater number of tumors ablated (P < .001), involvement of the middle or lower lobe (P = .008), and increased length of the aerated lung traversed by the electrode (P = .014). For pleural effusion, risk factors included the use of a cluster electrode (P = .008), decreased distance to the nearest pleura (P = .040), and decreased length of the aerated lung traversed by the electrode (P = .019). For chest tube placement for pneumothorax, risk factors included no history of pulmonary surgery (P = .002), the use of a cluster electrode (P < .001), and involvement of the upper lobe (P < .001). CONCLUSION: Pneumothorax and pleural effusion can occur after RF ablation in patients with lung tumors, and chest tube placement for pneumothorax is sometimes required.

Percutaneous radiofrequency ablation combined with previous bronchial arterial chemoembolization and followed by radiation therapy for pulmonary metastasis from hepatocellular carcinoma.

A 56-year-old man had a lung metastasis from hepatocellular carcinoma 4.7 cm x 3.4 cm in size located directly adjacent to the pulmonary hilar vessels. The tumor was treated with radiofrequency ablation combined with earlier bronchial arterial chemoembolization and subsequent radiation therapy. A complete remission of the tumor has been observed for 6 months since completion of therapy. Considering that complete treatment of such an intermediate-sized tumor adjacent to the large vessels is usually difficult with radiofrequency ablation alone, this result suggests a possible role for combined therapy for pulmonary neoplasms.