Ablation Of Benign Thyroid Nodules Research Articles

[Radiofrequency ablation of benign thyroid nodules: A prospective, multi-institutional North American experience].

[Radiofrequency ablation of benign thyroid nodules: A prospective, multi-institutional North American experience].

Comparison of the Therapeutic Efficacy and Technical Outcomes between Conventional Fixed Electrodes and Adjustable Electrodes in the Radiofrequency Ablation of Benign Thyroid Nodules.

This study aimed to compare therapeutic efficacy and technical outcomes between adjustable electrode (AE) and conventional fixed electrode (FE) for radiofrequency ablation (RFA) of benign thyroid nodules. Between 2013 and 2021, RFA was performed on histologically proven benign thyroid nodules. For the AE method, AE length ≥ 1 cm with higher power and < 1 cm with lower power were utilized for ablating feeding vessels and nodules, especially those near anatomical structures, respectively. The therapeutic efficacy (volume reduction rate [VRR], complication rate, and regrowth rate) and technical outcomes (total energy delivery, ablated volume/energy, RFA time, and ablated volume/time) of FE and AE were compared. Continuous parameters were compared using a two-sample t-test or Mann-Whitney U test, and categorical parameters were compared using a chi-squared test or Fisher's exact test. A total of 182 nodules (FE: 92 vs. AE: 90) in 173 patients (mean age ± standard deviation, 47.0 ± 14.7 years; female, 90.8% [157/173]; median follow-up, 726 days [interquartile range, 441-1075 days]) were analyzed. The therapeutic efficacy was comparable, whereas technical outcomes were more favorable for AE. Both electrodes demonstrated comparable overall median VRR (FE: 92.4% vs. AE: 84.9%, P = 0.240) without immediate major complications. Overall regrowth rates were comparable between the two groups (FE: 2.2% [2/90] vs. AE: 1.1% [1/90], P > 0.99). AE demonstrated a shorter median RFA time (FE: 811 vs. AE: 627 seconds, P = 0.009). Both delivered comparable median energy (FE: 42.8 vs. AE: 29.2 kJ, P = 0.069), but AE demonstrated higher median ablated volume/energy and median ablated volume/time (FE: 0.2 vs. AE: 0.3 cc/kJ, P < 0.001; and FE: 0.7 vs. AE: 1.0 cc/min, P < 0.001, respectively). Therapeutic efficacy between FE and AE was comparable. AE demonstrated better technical outcomes than FE in terms of RFA time, ablated volume/energy, and ablated volume/time.

Prospects of laser ablation of benign thyroid nodules. Literature review

The article is a review of the literature on the use of laser thermal ablation (LTA) for the destruction of benign nodular formations of the thyroid gland. According to various data, up to 60 % of the treated nodes do not respond to this type of treatment and there is no consensus among researchers about the causes of LTA failures. When performing LTA, different wavelengths and radiation power are used, the number and duration of sessions and the amount of energy delivered to the node differ, all this contributes to a large variability in the response to treatment, makes it difficult to compare data, final assessment of the effectiveness and, to a certain extent, the safety of the method. Regarding the effect on the success of treatment of morphological features, size and position of the node in the thyroid gland, contradictory results are also presented in the literature. The high variability of treatment results makes some authors believe that the effect of laser ablation of thyroid nodes is unpredictable. It should also be noted that most often in studies, a decrease in the size of nodes is estimated, which in itself has questionable clinical significance, and data on the success of eliminating functional autonomy are ambiguous. Thus, despite almost a quarter of a century of using LTA for the treatment of nodular goiter and a large number of published studies, none of the fundamental questions concerning optimal schemes for conducting and improving the effectiveness of procedures, including in patients with functional autonomy and large nodular formations, has received a definitive answer.

Radiofrequency ablation of benign thyroid nodules: A prospective, multi-institutional North American experience

BackgroundRadiofrequency ablation for benign thyroid nodules aims to achieve a volume reduction rate of ≥50%. However, factors that predict treatment success have not been defined in a large-scale study. MethodsA prospective cohort study of biopsy-proven benign thyroid nodules treated with radiofrequency ablation at 3 institutions was performed. Patient demographics, nodule sonographic features, procedural data, and nodule volume reduction were evaluated. Binary logistic regression analysis was performed to identify features associated with treatment response. ResultsA total of 620 nodules were analyzed. The pooled median volume reduction rate at 12 months was 70.9% (interquartile range 52.9–86.6). At 1 year follow-up, 78.4% of nodules reached treatment success with a volume reduction rate ≥50%. The overall complication rate was 3.2% and included temporary voice changes (n = 14), vasovagal episodes (n = 5), nodule rupture (n = 3), and lightheadedness (n = 2). No permanent voice changes occurred. Four patients developed postprocedural hypothyroidism. Large baseline nodule volume (>20 mL) was associated with a lower rate of successful volume reduction (odds ratio 0.60 [0.37–0.976]). Large nodules achieved treatment success by 12-month follow-up at a rate of 64.5%, compared with 81.4% for small nodules and 87.2% for medium nodules. ConclusionTo our knowledge, this is the largest North American cohort of patients with benign thyroid nodules treated with radiofrequency ablation. Overall, radiofrequency ablation was an effective treatment option with a low risk of procedural complications. Large volume nodules (>20 mL) may be associated with a lower rate of successful reduction with radiofrequency ablation treatment.

SAT511 High Intensity Focused Ultrasound (HIFU) Ablation for Benign Thyroid Nodules: A Single-Center Cohort

Abstract Disclosure: M. Mavromati: None. P. Meyer: None. F. Vermeulen: None. M. Demarchi: None. E. Saiji: None. C. De Vito: None. F. Jornayvaz: None. S. Leboulleux: None. A. Wolff: None. F. Triponez: None. Introduction:Benign thyroid nodules may increase in size over time and cause local compressive symptoms. Current guidelines suggest surgery for benign symptomatic nodules, however, complications such as hypothyroidism, bleeding, infection and recurrent laryngeal nerve injury are of concern for a growing number of patients. Minimally invasive techniques may therefore be an alternative to surgical resection. The objective of our study was to evaluate the efficacy and safety of high intensity focused ultrasound (HIFU) ablation in a single-center cohort of benign symptomatic thyroid nodules.Materials and methods:Between February 2021 and May 2022, 13 patients were treated by HIFU for a single benign solid symptomatic thyroid nodule. Benign nature of thyroid nodules was confirmed by a Bethesda II result in fine-needle aspiration, before HIFU. Treatment was performed under hypnosis, carried out by an experienced anesthesiologist. Patients were evaluated by clinical examination and ultrasound at 6 and 12 months after treatment. Results: A total of 13 patients (12 female and 1 male) were treated with HIFU for a single solid symptomatic benign thyroid nodule. Mean age was 57 years (range: 48-67 years). Thyroid nodules had an mean maximum diameter of 48 mm (range: 31-66 mm) and a meanvolume of 28.4 mL (range: 8.5-53 mL). At 12 months after HIFU, 4 patients underwent surgical ablation (31%) because of nodule growth (n=2, 15.4%) or persistent local compression (n=2, 15.4%). Those nodules were benign on final histology. Among non-operated nodules, mean decrease of volume at 6 months was 35% (range: 20-46%) and smaller nodules showed a better response to treatment. Altogether, 8 patients (61.5%) reported a clinical improvement 6 months after treatment, while 4 patients (31%) underwent surgery. Treatment was well tolerated in the majority of patients and had to be stopped because of pain in only one case (7.7%). There were no treatment-related local complications. Conclusion:High-intensity focused ultrasound (HIFU) ablation for benign symptomatic thyroid nodules is a safe minimally invasive technique but volume reduction was only 20-46% at 6 months, while 31% of patients required surgery after all. This could be attributed to the large initial volume of nodules included in our cohort. Clinical hypnosis is a useful alterative for pain management. Presentation Date: Saturday, June 17, 2023

SAT493 Laser Ablation For Benign Thyroid Nodules: A Way To Treat And Still Preserve The Thyroid

Abstract Disclosure: N. Kalara: None. D.L. Bignoli: None. C.M. Acosta: None. A. Manzano: None. Introduction: Thyroid nodules in adults have a prevalence of 3-7% based on palpation and 20-76% based on ultrasound examination. The majority of which are benign but some increase in size causing compressive symptoms or cosmetic concerns, thus, needing treatment. Laser ablation (LA) is a safe, non-surgical approach for the management of benign thyroid nodules now approved in the US. Nodule reduction is achieved through laser induced cytoreduction and tissue coagulation. Two benign FNA biopsies 3-6 months apart and a nodule size of more than 2.5 cm are some of the inclusion criteria for LA. We present a case of a benign thyroid nodule causing compressive symptoms where LA was done since the patient declined surgery. Case description: 76-year-old female with a history of type 2 diabetes mellitus, hypertension, and multinodular goiter for many years presented with concerns of neck fullness and discomfort for the past 6 months. Thyroid ultrasound confirmed a large dominant right complex nodule of 2.8 x 1.13 x 3 cm with a volume of 5 ml. Thyroid function test showed Thyroid stimulating hormone (TSH) 1.2 mIU/mL (0.40-4.50) and free T4 1.24 ng/dl (0.9-1.7). Two FNA biopsies done 3 months apart in the past were Bethesda II. Given the compressive symptoms due to a multinodular gland thyroidectomy was discussed as a treatment option with the patient which she declined. Hence, LA was discussed as an option for the largest nodule. The procedure was performed without complications. The nodule received 1450 Joules at 6 watts using one Elesta laser fiber. At the end of 2 months post-LA, thyroid ultrasound showed a significant reduction of the nodule with a current size of 1.5 x 1 x 1.6 cm and 1.4ml volume. She continued to be clinically and biochemically euthyroid with a total volume reduction close to 70% and complete resolution in compressive symptoms. Conclusion: Percutaneous laser ablation is a non-surgical, minimally invasive procedure to treat benign thyroid nodules that is now accessible in the US with promising results and a good safety profile. It is covered by insurance in various states. In our case the patient refused surgical intervention, thus, laser ablation was done that resulted in the resolution of her compressive symptoms without any complications. More awareness regarding the laser ablation procedure and its availability for patients is needed, especially in cases where preservation of the thyroid gland is desired. Reference: 1. Gambelunghe G, Stefanetti E, Avenia N, De Feo P. Percutaneous Ultrasound-Guided Laser Ablation of Benign Thyroid Nodules: Results of 10-Year Follow-Up in 171 Patients. J Endocr Soc. 2021 May 5;5(7):bvab081. doi: 10.1210/jendso/bvab081. PMID: 34159286; PMCID: PMC8212682. Presentation Date: Saturday, June 17, 2023

Clinical practice guidelines for radiofrequency ablation of benign thyroid nodules and malignant thyroid cancers: A systematic review

Clinical practice guidelines for radiofrequency ablation of benign thyroid nodules and malignant thyroid cancers: A systematic review

Volume reduction rate's predictors after radiofrequency ablation of benign thyroid nodules. a single-centre analysis

Volume reduction rate's predictors after radiofrequency ablation of benign thyroid nodules. a single-centre analysis

Initial ablation radio predicting volume reduction from microwave ablation of benign thyroid nodules.

Our research sought to investigate the relationship between initial ablation ratio (IAR) and internal composition of benign thyroid nodules treated by microwave ablation (MWA). Patients who underwent MWA at the Affiliated Hospital of Jiangsu University from January 2018 to December 2022 were enrolled in our research. All the patients were followed up for at least one year. We analyzed the relationship between IAR at 1 month of solid nodules (solid >90%), predominantly solid nodules (90% >solid > 75%), mixed solid alongside cystic nodules (75% >solid > 50%) as well as volume reduction rate (VRR) at 1, 3, 6 and 12 months follow-up. The mean IAR of the solid nodules (solid >90%) was 94.32±7.87%,#x0025;, that of the predominantly solid nodules (90% >solid > 75%) and mixed solid alongside cystic nodules (75% >solid > 50%) were 86.51±6.66% and 75.19±4.97%,#x0025;, respectively. Almost all the thyroid nodules were significantly decreased in size after MWA. After 12 months of MWA treatment, the average volume of the aforementioned thyroid nodules decreased from 8.69±8.79 to 1.84±3.11 ml, 10.94±9.07 to 2.58±3.34 ml, 9.92±6.27 to 0.25±0.42 ml, respectively. The mean symptom and cosmetic scores of the nodules showed significant (p < 0.000) improvement. The rates of the complications or side effects of MWA against the above-mentioned nodule types were 8.3% (3/36), 3.2% (1/31) and 0% (0/36), respectively. The application of the IAR to quantify the success rate of thyroid nodule microwaves in the short term demonstrated that IAR was related to the internal components of the nodule. Although the IAR was not high when the thyroid component was mixed solid and cystic nodules (75% >solid > 50%), the final therapeutic effect was still satisfactory.

Ultrasound-Guided Radiofrequency Ablation versus Thyroidectomy for the Treatment of Benign Thyroid Nodules in Elderly Patients: A Propensity-Matched Cohort Study.

Ultrasound-guided radiofrequency ablation has been recommended as an alternative to surgery for benign thyroid nodules. However, little is known about the benefit from the application of radiofrequency ablation for benign thyroid nodules in elderly patients. The purpose of this study was to compare the clinical outcomes of radiofrequency ablation versus thyroidectomy for elderly patients with benign thyroid nodules. This retrospective study evaluated 230 elderly patients (60 years of age or older) with benign thyroid nodules treated with radiofrequency ablation (R group, n = 49) or thyroidectomy (T group, n = 181). Complications, thyroid function, and treatment variables, including procedural time, estimated blood loss, hospitalization, and cost, were compared after propensity score matching. The volume, volume reduction rate, symptoms, and cosmetic score were also evaluated in the R group. After 1:1 matching, each group had 49 elderly patients. The rate of overall complications and hypothyroidism was 26.5% and 20.4% in the T group, respectively, but these complications were totally absent from the R group (P < .001, P = .001). Patients in the R group had a significantly shorter procedural time (median, 4.8 versus 95.0 minutes, P < .001) and lower cost (US $1979.02 versus US $2208.80, P = .013) than those treated by thyroidectomy. After radiofrequency ablation, the volume reduction rate was 94.1%, and 12.2% of nodules had completely disappeared. The symptom and cosmetic scores were both significantly reduced at the last follow-up. Radiofrequency ablation could be considered as a first-line treatment for elderly patients with benign thyroid nodules.

Effizienz und Sicherheit der Radiofrequenzablation benigner Schilddrüsenknoten

Effizienz und Sicherheit der Radiofrequenzablation benigner Schilddrüsenknoten

Ultrasound-guided microwave ablation for benign thyroid nodules results in earlier and faster nodule shrinkage in patients with Hashimoto's thyroiditis than in those with normal thyroid function.

Given that the histological features of the thyroid parenchyma in patients with Hashimoto's thyroiditis (HT) differ from those of the normal thyroid gland, HT may affect the effectiveness of ultrasound-guided microwave ablation (MWA) for benign thyroid nodules (BTNs). The present study aimed to compare the effectiveness of MWA for the treatment of BTNs in patients with both BTNs and HT and those with BTNs and normal thyroid function, based on changes in the volume reduction ratio (VRR) of the BTNs. Patients who had achieved a VRR ≥50% after MWA for BTN (July 2020-June 2021), followed up for 12 months, and their data were retrospectively analyzed. A total of 213 nodules were identified in 185 patients, including 167 in the "BTN" group and 46 in the "BTN + HT" group. A comparison of the fitting curves for VRR-follow-up time revealed that the VRR increased with time after MWA, although the relationship was nonlinear. Piece-wise linear regression model analysis of the threshold effect of VRR and follow-up time in the two groups indicated that the inflection point of the "BTN" group occurred at 2.1 months: VRR increased fastest within 2.1 months of MWA (rate of change: 32.9% per month; P < 0.001), following which the rate of change was slower and maintained at 1.0% per month (P = 0.006). In the "BTN + HT" group, the inflection point occurred 1.5 months after MWA, with the most significant increase occurring in this period (rate of change: 41.5% per month; P < 0.001), followed by a rate of 2.8% per month (P < 0.001) after 1.5 months. The relationship between VRR and follow-up time for ultrasound-guided MWA for BTN is nonlinear and exhibits a threshold effect. The current results indicated that the VRR in both groups increased before and after the inflection point, although the rate of change was greater before than after the inflection point. The inflection point occurs earlier in patients with BTN + HT than in those with BTN yet normal thyroid function, and this difference may be related to the "oven effect" involved in the development of HT.

["Leverage pry-off method" for effective prevention of thermal injury during microwave ablation of benign thyroid nodules].

To assess the safety and efficacy of"leverage pry-off method"for preventing thermal injury during microwave ablation of benign thyroid nodules. From July, 2017 to September, 2019, a total of 348 patients with benign thyroid nodules underwent ultrasound-guided microwave ablation. For protecting from thermal injury during the ablation, "hydrodissection technique" was used in 174 of the patients (admitted from July, 2017 to August, 2018) and "leverage pry-off method" in the other 174 patients (admitted from September, 2018 to September, 2019). All the patients were followed up for 1 to 12 months after the operation for observation of severe complications and nodular residues. Ultrasound-guided microwave ablation was completed in all the 348 patients. The most common severe complication associated with the ablation was voice change, occurring in 3 cases (1.7%) in "hydrodissection technique" group and in 4 (2.3%) in the "leverage pry-off method" group, showing no significant difference between the two groups (P>0.05). During the follow-up, no significant difference was found in the rate of nodular residues between the "hydrodissection technique" group and "hydrodissection technique" group (9.8% vs 10.9% (P>0.05). The "leverage pry-off method" is simple and effective for preventing thermal injury during microwave ablation of benign thyroid nodules.

[Effective and Safe Application of Radiofrequency Ablation for Benign Thyroid Nodules].

Radiofrequency ablation (RFA) has been a representative, non-surgical treatment for benign thyroid nodules that cause cosmetic problems or compression symptoms. The procedure of RFA should be performed effectively and safely. This review discusses the patient selection, pre-procedure evaluation and planning, principles, devices, techniques, and complications with reference to the guidelines and research on thyroid RFA. In particular, this review will devote to introduce RFA techniques and to provide practical help in the implementation of this procedure.

[Does preoperative risk grading have clinical value for benign thyroid nodular ablation?]

To explore the risk grading method for benign thyroid nodules before microwave ablation and the clinical significance of risk grading. This study was conducted among 527 patients undergoing ultrasound-guided microwave ablation of benign thyroid nodules between July, 2017 and December, 2020.Based on anatomic relationship of the thyroid nodules with the adjacent tissues, the ablation risk was classified into 4 levels: low, medium, high and extremely high risks.The incidence of severe complications and the rate of residual nodules following the ablation were recorded. In the patients graded to have low, medium, high and extremely high preoperative risks, the incidences of severe complications following the ablation were 0%, 0.88%, 2.41% and 6.78%, respectively, showing no significant differences among the different risk groups (P > 0.05).The rates of postoperative residual nodules in the 4 risk groups were 1.59%, 6.14%, 14.43% and 71.19%, respectively, showing a significant difference between the low and medium risk groups and the high and extremely high risk groups (P < 0.001). Preoperative risk grading for thyroid nodular ablation can be helpful for prevention of severe complications during ablation and prediction of residual nodules after ablation.

Changes in Thyroid Antibodies after Microwave Ablation of Thyroid Nodules

Purpose Microwave ablation (MWA) is a minimally invasive method for the thermal ablation of benign thyroid nodules and papillary thyroid cancer (PTC) and has shown promising results. The aim of this study was to investigate the impact of MWA on thyroid antibodies and associated influencing factors. Materials and Methods A total of 119 patients, including 69 with benign thyroid nodules and 50 with PTC, underwent MWA between June 2019 and June 2021. The serum levels of (free) triiodothyronine, (free) thyroxine, thyrotropin, and antibodies against Tg (TGAb), thyrotropin receptors (TRAb), and thyroid peroxidase (TPOAb) were measured during the follow up. Results One month after ablation, three patients (4.3%) in the benign group had hypothyroidism, and one (1.4%) had hyperthyroidism. Four patients (5.8%) had subclinical hypothyroidism, and two (2.9%) had subclinical hyperthyroidism. Among the PTC patients, two (4%) had hypothyroidism, and one (2%) had hyperthyroidism. Two patients (4%) had subclinical hypothyroidism, and one (2%) had subclinical hyperthyroidism. In the benign group, among patients with normal preablation antibodies, the postablation TGAb abnormal rate was 12.7%, the TPOAb level was 4.8%, and the TRAb level was 0%. Among PTC patients, the postablation TGAb abnormal rate was 11.4%, the TPOAb level was 8.7%, and the TRAb level was 4.0%. The cutoff value of preablation TGAb for predicting postoperative antibody abnormalities was 19.0 IU/mL, while that of TPOAb was 11.4 IU/mL. Conclusions MWA of thyroid nodules had little influence on thyroid function and antibodies. Elevations in TGAb, TPOAb, and TRAb beyond the normal ranges after MWA may be related to high preablation levels of TGAb and TPOAb.

Residual, regrowth, and new growth of radiofrequency ablation for benign thyroid nodules of different volumes: two-year follow-up results

Introduction Radiofrequency ablation (RFA) is recognized as an effective technique for the treatment of benign thyroid nodules (BTNs), although the long-term results are limited. This study aimed to evaluate the residual vital volume increase, regrowth, and new growth over a 2-year period after RFA among different nodule volume groups. Subjects and Methods This retrospective study evaluated 135 patients with 153 BTNs who underwent ultrasound guided RFA. The BTNs were categorized into small (<10 mL), medium (10–30 mL), and large (>30 mL) according to the initial volume of BTNs prior to ablation. The volume changes of each nodule were analyzed at 1, 3, 6, 12 and 24 months after RFA. New growth was defined as the growth in volume not found in the early follow-up on ultrasonography. Results The initial ablation ratio of all BTNs was 99.67%. The mean volume reduction ratio (VRR) of BTNs was 85.53% after 2-year follow-up. The small nodule group showed a lower VRR compared to the other two groups at the 1-month follow-up, and there was no difference of VRR at the subsequent follow-ups. The incidence of residual vital volume increase was 4.58%. The overall incidence of regrowth was 3.92% and the mean timing of regrowth was 16.71 months. New growth occurred in 18.95% of patients. No further treatment was required in the majority of cases. Conclusion RFA achieved a clinically relevant volume reduction in different sizes of single BTNs which persisted for at least 2 years, thereby preventing the need for retreatment.

Radiofrequency Ablation for Benign Thyroid Nodules: Radiology In Training.

Two patients, one with benign nonfunctioning nodules and one with functioning thyroid nodules, both of whom underwent radiofrequency ablation, are presented. Preprocedural evaluation, procedural considerations, and follow-up care of thyroid radiofrequency ablation, as well as published evidence on the topic, are discussed.

Long-term outcome of microwave ablation for benign thyroid nodules: Over 48-month follow-up study.

ObjectivesThe short-term effects of microwave ablation (MWA) for the treatment of benign thyroid nodules (BTNs) were satisfactory in previous studies. However, as a slowly progressing disease, the long-term efficacy of MWA for BTNs at present is not clear. Our study aim was to assess the long-term results of MWA for BTNs after a 48-month follow-up.MethodsFrom June 2015 to September 2017, 148 patients had 148 BTNs. All patients were from the China-Japan Union Hospital of Jilin University. Careful ultrasound examinations were performed 1 day, 1 month, 3 months, 6 months, 12 months, and every 6 months after MWA. The volume, volume reduction rate (VRR), recurrence rate of the ablated area and thyroid function were recorded.ResultsThe mean volumes of the 148 nodules were 15.6 ± 9.4 cm3 (range: 1.3-48.9 cm3) and 0.6 ± 0.6 cm3 (range: 0-3.5 cm3) before and 48 months after MWA, respectively, with a nodule VRR of 96.9 ± 2.5% (range: 90.4-100%). Two patients (1.35%) had recurrence after MWA. Compared with thyroid function before MWA, no significant variation was observed after MWA. Five patients experienced complications (3.38%): two patients (1.35%) had bleeding, two patients (1.35%) had ear pain and toothache during MWA, and one patient (0.68%) had hoarseness after MWA. No cases of oesophageal injury, tracheal injury, infection, skin burns, etc., were reported during or after MWA.ConclusionsBased on a long-term follow-up, MWA is an effective method for treating BTNs and is expected to be a potential first-line treatment.

Long-term follow-up of the radiofrequency ablation of benign thyroid nodules: the value of additional treatment.

PurposeThis study aimed to evaluate the efficacy of additional radiofrequency ablation (RFA) treatment for benign thyroid nodules.MethodsElectronic medical records at a single institution from September 2008 to August 2016 were searched, and consecutive patients treated with RFA due to benign thyroid nodules with cosmetic or symptomatic problems were enrolled. All patients were followed up for at least 30 months. The nodules were divided into three groups: group 1 included nodules that met the criteria for additional treatment and underwent additional treatment, group 2 included nodules that met the criteria but did not undergo additional treatment, and group 3 included nodules that did not meet the criteria. The ablation results were compared among the three groups in terms of the initial ablation ratio (IAR) and volume reduction ratio (VRR).ResultsNinety nodules from 88 patients were included in the study. At the last follow-up, group 1 showed a significantly smaller nodule volume and larger VRR (2.5 mL and 84.6%, respectively) than group 2 (8.1 mL and 39.8%, respectively, P<0.001), but did not present a significant difference from group 3 (0.9 mL, P=0.347, and 92.8%, P=0.238). The IAR was significantly higher in group 3 (94.5%) than in the other two groups (group 1, 81.1%; group 2, 82.8%; P<0.001).ConclusionMultiple treatment sessions achieve greater VRR. Therefore, additional treatment could be considered for patients who meet the corresponding criteria.