International Journal of Hyperthermia最新文献

Purpose: To investigate the value of susceptibility weighted imaging (SWI) for assessing the hyperacute outcome of ablation of uterine fibroids immediately after magnetic resonance-guided focused ultrasound (MRgFUS) treatment.

Methods: This retrospective imaging study included patients who underwent SWI and contrast-enhanced (CE) MR within 15 min of MRgFUS ablation for uterine fibroids. Two readers independently assessed the SWI features of ablative lesions and their association with the non-perfused volume (NPV) ratio. The intraclass correlation coefficient (ICC) and diagnostic value of SWI findings were calculated.

Results: A total of 27 uterine fibroids from 21 participants (mean age 40.1 ± 7.2 years) were analyzed. 51.9% (14/27) leiomyomas had NPV ratio ≥90%. In post-ablation SWI images, the interobserver ICC for the relative signal intensity and hypointense peripheral rim were 0.613 and 0.843, respectively (both p < .001). There was a significant difference in the prevalence of hypointense peripheral rim in leiomyomas with NPV ratio ≥90% and < 90% (p < .01), while the prevalence of relative signal intensity showed no significant difference (p > .05). When using the complete hypointense peripheral rim as a diagnostic criterion to identify NPV ratio ≥ 90%, readers 1 and 2 showed diagnostic sensitivity, specificity, and accuracy of 85.7%, 76.9%, 81.5%, and 78.6%, 76.9%, 77.8%, respectively.

Conclusion: Identifying a complete hypointense peripheral rim on SWI may be a potential imaging marker for assessing the hyperacute outcome of uterine fibroids ablation by MRgFUS, specifically in determining whether the NPV ratio is ≥90%.

Purpose: To use computational modeling to provide a complete and logical description of the electrical and thermal behavior during stereoelectroencephalography-guided (SEEG) radiofrequency thermo-coagulation (RF-TC).

Methods: A coupled electrical-thermal model was used to obtain the temperature distributions in the tissue during RF-TC. The computer model was first validated by an ex vivo model based on liver fragments and later used to study the impact of three different factors on the coagulation zone size: 1) the difference in the tissue surrounding the electrode (gray/white matter), 2) the presence of a peri-electrode gap occupied by cerebrospinal fluid (CSF), and 3) the energy setting used (power-duration).

Results: The model built for the experimental validation was able to predict both the evolution of impedance and the short diameter of the coagulation zone (error < 0.01 mm) reasonably well but overestimated the long diameter by 2 - 3 mm. After adapting the model to clinical conditions, the simulation showed that: 1) Impedance roll-off limited the coagulation size but involved overheating (around 100 °C); 2) The type of tissue around the contacts (gray vs. white matter) had a moderate impact on the coagulation size (maximum difference 0.84 mm), and 3) the peri-electrode gap considerably altered the temperature distributions, avoided overheating, although the diameter of the coagulation zone was not very different from the no-gap case (<0.2 mm).

Conclusions: This study showed that computer modeling, especially subject- and scenario-specific modeling, can be used to estimate in advance the electrical and thermal performance of the RF-TC in brain tissue.

Purpose: The treatment of recurrent thyroid cancer with critical organ invasion is challenging. The combination of radiofrequency ablation (RFA) and external beam radiation therapy (EBRT) has been proposed as an effective option. This study evaluates outcomes for inoperable residual/recurrent differentiated thyroid cancer (rDTC) patients treated with RFA followed by EBRT.

Materials and methods: Patients with rDTC treated with RFA followed by EBRT were retrospectively studied. RFA was performed using a free-hand, 'moving-shot' technique under US or CT guidance. For lesions invading critical structures intolerant to 'en bloc' high-temperature RFA, limited-field EBRT using 6- or 10-MV photons was used for adjuvant treatment at a dose of 66 Gy in 33 daily fractions. Toxicities and outcomes were reviewed.

Results: Between April 2020 and January 2022, 11 patients with 14 rDTC lesions underwent RFA followed by EBRT. Five patients had metastatic lesions at rDTC diagnosis. With a median follow-up period of 33.7 months, all patients maintained locoregional control, while achieving a 2-year survival rate of 90.9%. This combined treatment achieved a volume reduction ratio of 92.1% ± 5.1%. The mean nadir thyroglobulin level in patients without initial distant metastases after treatment was 1.40 ± 0.81 ng/ml. Regarding treatment-related complications, one patient (9%) experienced temporary hoarseness after RFA, grade 2 radiation dermatitis occurred in 3 patients (27.2%), and grade 2 dysphagia was noted in 4 patients (36.4%). No grade 3 or greater toxicities occurred.

Conclusions: Salvage RFA followed by EBRT is feasible, effective and safe for patients with rDTC.

Background: The greater omentum is routinely resected during cytoreductive surgery (CRS), but few studies have analyzed the rationale behind this. This study aimed to assess the prevalence of omental metastases (OM) and the correlation between macroscopically suspected and microscopically confirmed OM, in patients with pseudomyxoma peritonei (PMP) or colorectal peritoneal metastases (PM).

Method: All patients without previous omentectomy, treated with initial CRS and hyperthermic intraperitoneal chemotherapy for PMP or colorectal PM, at Uppsala University Hospital in 2013-2021, were included. Macroscopic OM in surgical reports was compared with histopathological analyses.

Results: In all, 276 patients were included. In those with PMP, 112 (98%) underwent omentectomy and 67 (59%) had macroscopic suspicion of OM. In 5 (4%) patients, the surgeon was uncertain. Histopathology confirmed OM in 81 (72%). In patients with macroscopic suspicion, 96% had confirmed OM (positive predictive value, PPV). In patients with no suspicion, 24% had occult OM (negative predictive value, NPV = 76%). In patients with colorectal PM, 156 (96%) underwent omentectomy and 97 (60%) had macroscopic suspicion. For 5 (3%) patients, the surgeon was uncertain. OM was microscopically confirmed in 90 (58%). PPV was 85% and NPV was 89%. The presence of OM was a univariate risk factor for death in PMP (HR 3.62, 95%CI 1.08-12.1) and colorectal PM (HR 1.67, 95%CI 1.07-2.60), but not in multivariate analyses.

Conclusion: OM was common and there was a high risk of missing occult OM in both PMP and colorectal PM. These results support the practice of routine omentectomy during CRS.

Objective: To compare the efficacy and safety of high-intensity focused ultrasound (HIFU) and radical surgery for non-metastatic pancreatic cancer (PC).

Materials and methods: We retrospectively analyzed 89 stage I/II/III PC patients who underwent HIFU (n = 43) or surgery (n = 46) at the Third Xiangya Hospital from January 2020 to December 2021. Pain relief, Karnofsky Performance Scale (KPS), overall survival (OS), treatment-related complications and risk factors for OS were assessed.

Results: There was no significant difference in the pain relief rate at 30 days post-treatment between the two groups. However, compared with the surgery group, the HIFU group showed significantly lower post-treatment VAS scores (p = 0.019). In the surgery group, the KPS at 30 days post-treatment was lower than pretreatment KPS (70 vs 80; p = 0.015). This relationship was reversed in the HIFU group (80 vs 70; p = 0.024). Median OS favored surgery over HIFU (23 vs 10 months; p < 0.001), with a higher 1-year OS rate (69.57% vs 32.6%; p < 0.001). However, there was no significant difference in OS between the two groups for stage III patients (p = 0.177). Complications rated ≥ grade III were 2.33% in the HIFU group and 32.6% in the surgery group. Multivariate analyses showed that age, KPS, and treatment methods were independent prognostic factors for OS.

Conclusion: HIFU demonstrates advantages over surgery in terms of early KPS, VAS improvements, and safety for pancreatic cancer; however, long-term outcomes favor surgery. For III-stage disease, HIFU was noninferior to surgery in overall survival.

Background: Despite the theoretical advantages of treating metastatic bone disease with microwave ablation (MWA), there are few reports characterizing microwave absorption and bioheat transfer in bone. This report describes a computational modeling-based approach to simulate directional microwave ablation (dMWA) in spine, supported by ex vivo and pilot in vivo experiments in porcine vertebral bodies.

Materials and methods: A 3D computational model of microwave ablation within porcine vertebral bodies was developed. Ex vivo porcine vertebra experiments using a dMWA applicator measured temperatures approximately 10.1 mm radially from the applicator in the direction of MW radiation (T1) and approximately 2.4 mm in the contra-lateral direction (T2). Histologic assessment of ablated ex vivo tissue was conducted and experimental results compared to simulations. Pilot in vivo experiments in porcine vertebral bodies assessed ablation zones histologically and with CT and MRI.

Results: Experimental T1 and T2 temperatures were within 3-7% and 11-33% of simulated temperature values. Visible ablation zones, as indicated by grayed tissue, were smaller than those typical in other soft tissues. Posthumous MRI images of in vivo ablations showed hyperintensity. In vivo experiments illustrated the technical feasibility of creating directional microwave ablation zones in porcine vertebral body.

Conclusion: Computational models and experimental studies illustrate the feasibility of controlled dMWA in bone tissue.

Objective: A meta-analysis was conducted to assess the efficacy and safety of cryoablation (CRA) compared with radiofrequency ablation (RFA).

Methods: A systematic search of PubMed, EMBASE, Cochrane Library, Wanfang, CNKI, and VIP databases was conducted to identify clinical controlled studies comparing CRA versus RFA for hepatic malignancies up to July 2022. The meta-analysis was performed using RevMan 5.3.

Results: A comprehensive analysis was conducted on 8 clinical controlled studies involving a total of 943 patients. There were no significant differences in the incidence of complications, complete ablation of lesions, local recurrence, and 1-year survival between the CRA and RFA groups (OR = 0.98, 95%CI: 0.61-1.55, p = 0.92; OR = 1.08, 95%CI: 0.62-1.90, p = 0.78; OR = 1.28, 95%CI: 0.49-3.36, p = 0.61; and OR = 1.14, 95%CI: 0.63-2.06, p = 0.66, respectively).

Conclusion: The efficacy and safety profile of CRA was comparable to that of RFA in the context of ablation therapy for hepatic malignancies. These findings suggested that CRA may be a valuable alternative to RFA in the treatment of hepatic malignancies.

Purpose: Cisplatin is commonly prescribed in hyperthermic intraperitoneal chemotherapy (HIPEC) for peritoneal malignancy. Acute kidney injury (AKI) is regarded as a common complication after HIPEC combined with cytoreductive surgery (CRS). However, post-HIPEC chronic kidney disease (CKD) is scarce and less investigated. This study aims to investigate the incidence of CKD following cisplatin-based HIPEC and to analyse the associated risk factors.

Materials and methods: From January 2016 to August 2021, a total of 55 patients treated with CRS and cisplatin-based HIPEC for peritoneal carcinomatosis were categorized retrospectively into groups, with and without CKD. Demographics, comorbidity, surgery, postoperative management, and complications were collected to evaluate risk factors for cisplatin-based HIPEC-related CKD. Univariate and multivariate analyses were conducted to confirm the correlation between different variables and CKD occurrence.

Results: Of the 55 patients, 24 (43.6%) patients developed AKI and 17 (70.8%) patients of these AKI patients progressed to CKD. Multivariate regression analysis identified intraoperative use of parecoxib (Odds Ratio (OR) = 4.39) and intraoperative maximum temperature > 38.5°C (OR = 6.40) as major risk factors for cisplatin-based HIPEC-related CKD occurrence. Though type II diabetes mellitus and intraoperative complications were the independent risk factors of AKI following cisplatin-based HIPEC, but they were not shown in CKD analysis.

Conclusion: Intraoperative use of parecoxib during cisplatin-based HIPEC emerged as a significant risk factor for postoperative CKD. Clinicians should exercise caution in prescribing parecoxib during HIPEC procedures. Additionally, maintaining intraoperative body temperature below 38.5°C might be crucial to mitigate the risk of CKD development. This study underscores the importance of identifying and preventing specific risk factors to improve long-term renal outcomes in patients undergoing cisplatin-based HIPEC.

Purpose: This retrospective, single-center, case-control study evaluated the safety and efficacy of Computed tomography (CT)-guided microwave ablation (MWA) for pulmonary nodules located in the right middle lobe (RML), a challenging location associated with a high frequency of complications.

Methods: Between May 2020 and April 2022, 71 patients with 71 RML pulmonary nodules underwent 71 MWA sessions. To comparison, 142 patients with 142 pulmonary nodules in non-RML were selected using propensity score matching. The technical success, technique efficacy, complications, and associated factors were analyzed. The duration of the procedure and post-ablation hospital stay were also recorded.

Results: Technical success was achieved in 100% of all patients. There were no significant differences in technique efficacy rates between the RML and non-RML groups (97.2% vs. 95.1%, p = 0.721). However, both major (47.9% vs. 19.7%, p < 0.001) and minor (26.8% vs. 11.3%, p = 0.004) pneumothorax were more common in the RML group than non-RML group. MWA for RML pulmonary nodules was identified as an independent risk factor for pneumothorax (p < 0.001). The duration of procedures (51.7 min vs. 35.3 min, p < 0.001) and post-ablation hospital stays (4.7 days vs. 2.8 days, p < 0.001) were longer in the RML group than non-RML group.

Conclusions: CT-guided MWA for RML pulmonary nodules showed comparable efficacy compared with other lobes, but posed a higher risk of pneumothorax complications, necessitating longer MWA procedure times and extended hospital stays.

Objectives: To evaluate the feasibility, efficacy, and safety of radiofrequency ablation (RFA) for solitary T1N0M0 papillary thyroid carcinoma (PTC) in the danger triangle area.

Methods: 94 participants (mean age 44.45 ± 13.08; 73 females) with solitary T1N0M0 PTC in the danger triangle area who underwent percutaneous RFA at the hospital from January 2018 to April 2020 were retrospectively analyzed. Key ablation procedures included sufficient paratracheal fluid isolation, low-power, and short active tip (5 mm working electrode). Tumor size changes at different time points after RFA, technical success rates, tumor disappearance, disease progression, and complications were recorded and compared.

Results: Contrast-enhanced ultrasonography revealed that complete tumor ablation was performed with a 100% success rate in these patients. Post-ablation, the maximum diameter and volume of the ablation zone increased at the first and third month (p < 0.001), followed by a gradual decrease in size, without significant difference by the 6th month. The tumor disappearance rate was 76.59% (72/94), with higher rates in the T1a group compared to the T1b group (80% [64/80] VS57.1% [8/14], p < 0.001). There were no local recurrences. The incidence of new lesions and LNM was 3.2% (3/94), limited to the T1a subgroup. Further ablation was successfully applied to all new lesions and LMN. Mild voice changes were the only complication, with a rate of 3.2% (3/94), resolved within 4 months after RFA.

Conclusions: Sufficient paratracheal fluid isolation combined with a low-power, short active tip radiofrequency ablation strategy is a safe and effective method for treating solitary T1N0M0 PTC in the danger triangle area.