Nodule Volume Research Articles

RF11 | PSAT234 Deep learning analysis of thyroid nodule ultrasound images has high sensitivity and negative predictive value to rule-out thyroid cancer

Abstract Purpose To evaluate deep learning analysis of thyroid nodule ultrasound images as a rule-out test for thyroid malignancy. Methods Supervised deep learning (DL) classifier of thyroid nodules was trained on 32,545 thyroid US images from 621 nodules representing all major benign and malignant types of thyroid lesions and tested on an independent set of 145 nodules collected at a different healthcare system in the United States. The Big Transfer BiT-M ResNet-50×1 convolutional neural net architecture was modified to contain 3, 4, 6 and 3 PreActBottleneck units per block 1 through 4. Weights pretrained on the ImageNet-21k dataset were loaded and weights for blocks 3 and 4 were fine-tuned for the binary classification task of distinguishing benign and malignant thyroid nodules. Results The deep learning thyroid nodule classifier achieved an area under receiver operating characteristic curve (AUROC) of 0.889 on five-fold cross-validation. The AUROC improved when images were scaled by nodule size and six randomly selected cine clip frames were added to the training set per epoch. GradCAM class activation heatmaps revealed that microcalcifications and spongiform appearance were reliably recognized by the classifier as malignant and benign features, respectively. Spongiform nodules were found to be benign even when microcystic spaces constituted less than 50% of nodule volume. To investigate the clinical relevance of the benign vs. malignant classifier, the binary classification threshold for the probability of malignancy generated by model was set at 7% to achieve sensitivity and negative predictive value (NPV) comparable to that of the fine needle aspiration biopsy (FNA). At this threshold, cross-validated deep-learning model achieved a sensitivity of 90%, specificity of 63%, positive predictive value (PPV) of 46% and negative predictive value of 94%. When tested on an independent image set that includes 18 classic papillary thyroid cancers (PTC), 5 follicular variant PTC, 4 medullary thyroid cancers, 3 follicular thyroid cancers (FTC), and 1 Hurthle cell thyroid cancer, the DL classifier achieved AUROC of 0.88, sensitivity of 97%, specificity of 61%, PPV of 40% and NPV of 99%. A single minimally-invasive FTC that had no suspicious features on thyroid ultrasound was incorrectly classified as benign. Conclusions This study demonstrates that the ultrasound-based deep-learning classifier of thyroid nodules achieves sensitivity and negative predictive value comparable to that of thyroid fine needle aspiration (FNA). Clinicians may use this tool to augment clinical judgment when determining whether to perform FNA procedures. Presentation: Saturday, June 11, 2022 1:00 p.m. - 3:00 p.m., Saturday, June 11, 2022 1:06 p.m. - 1:11 p.m.

Efffects of Rhizobium Inoculation, Sulphur and Zinc Nutrients on Yield and Yield Componets of Chickpea (Cicer aritienum L.) at Gewane, Northeastern Ethiopia


 The goal of this study was to see how a combination of Rhizobium inoculant, S, and Zn nutrients affected chickpea nodulation and yield (Cicer arientinum L.) at Gewane, northeastern Ethiopia. The experiment included 12 treatments arranged in factorial combination of levels of inoculation (Rhizobium inoculated, un-inoculated), three rates of S (0, 15, 30 kg Sulphur ha-1) and rates of Zn (0, 1.5 kg Zinc ha-1). The treatment becomes laid out in randomized complete block design with 3 replications. Analysis of variance showed that yield and yield associated parameters (main branches, number of pod, quantity of seed, hundred seed weight, grain and straw yield), crop phenology (days to 50% flowering and days to physiological maturity), nodulation scores (nodule amount, nodule volume, nodule dry weight, effective nodule and nodulation score), N and P uptake at both locations had been significantly affected by the treatments. The best (1775.5 kg ha-1) suggest rate of seed yield over locations changed into acquired from blended costs of rhizobium and 30 kg S ha-1 which led to 28 % (389 kg ha-1) growth over the control. Consequently, rhizobium inoculation with rate of 30 kg S ha-1is recommended for chickpea production on the experimental site.

Comparison of Two-dimensional and Three-dimensional Features of Chest CT in the Diagnosis of Invasion of Pulmonary Ground Glass Nodules

At present, more and more studies predict invasive adenocarcinoma (IAC) through three-dimensional features of pulmonary nodules, but few studies have confirmed that three-dimensional features have more advantages in diagnosing IAC than traditional two-dimensional features of pulmonary nodules. This study analyzed the differences of chest computed tomography (CT) features between IAC and minimally invasive adenocarcinoma (MIA) from three-dimensional and two-dimensional levels, and compared the ability of diagnosing IAC. The non-invasive adenocarcinoma group includes precursor glandular lesions (PGL) and minimally invasive adenocarcinoma (MIA). The clinical data of 1,045 patients with ground glass opacity (GGO) from January to December 2019 were collected. Then the correlation between preoperative CT image characteristics and pathological results were analyzed retrospectively. The independent influencing factors for the identification of IAC were screened out according to two-dimensional and three-dimensional classification by multivariate Logistic regression and the cut-off point for the identification of IAC was found out through the receiver operating characteristic (ROC) curve. At last, the ability of diagnosing IAC was evaluated by Yoden index. The diameter of nodule, the diameter of solid component, the diameter of mediastinal window nodule in two-dimensional factors, and the volume of nodule, the volume of solid part and the average CT value in three-dimensional factors were independent risk factors for the diagnosis of IAC. These factors were arranged by Yoden index: solid partial volume (0.601)>nodule volume (0.536)>solid component diameter (0.525)>nodule diameter (0.518)>mediastinal window nodule diameter (0.488)>proportion of solid component volume (0.471)>1-tumor disappearance ratio (TDR) (0.468)>consolidation tumor ratio (CTR) (0.394)>average CT value (0.380). The CT features of three-dimensional are better than two-dimensional in the diagnosis of IAC, and the size of solid components is better than the overall size of nodules.

Semi-automated volumetry of pulmonary nodules: Intra-individual comparison of standard dose and chest X-ray equivalent ultralow dose chest CT scans

PurposeTo assess the performance of semi-automated volumetry of solid pulmonary nodules on single-energy tin-filtered ultralow dose (ULD) chest CT scans at a radiation dose equivalent to chest X-ray relative to standard dose (SD) chest CT scans and assess the impact of kernel and iterative reconstruction selection. MethodsNinety-four consecutive patients from a prospective single-center study were included and underwent clinically indicated SD chest CT (1.9 ± 0.8 mSv) and additional ULD chest CT (0.13 ± 0.01 mSv) in the same session. All scans were reconstructed with a soft tissue (Br40) and lung (Bl64) kernel as well as with Filtered Back Projection (FBP) and Iterative Reconstruction (ADMIRE-3 and ADMIRE-5). One hundred and forty-eight solid pulmonary nodules were identified and analysed by semi-automated volumetry on all reconstructions. Nodule volumes were compared amongst all reconstructions thereby focusing on the agreement between SD and ULD scans. ResultsNodule volumes ranged from 58.5 (28.8–126) mm3 for ADMIRE-5 Br40 ULD reconstructions to 72.5 (39–134) mm3 for FBP Bl64 SD reconstructions with significant differences between reconstructions (p < 0.001). Interscan agreement of volumes between two given reconstructions ranged from ICC = 0.605 to ICC = 0.999. Between SD and ULD scans, agreement of nodule volumes was highest for FBP Br40 (ICC = 0.995), FBP Bl64 (ICC = 0.939) and ADMIRE-5 Bl64 (ICC = 0.994) reconstructions. ADMIRE-3 reconstructions exhibited reduced interscan agreement of nodule volumes (ICCs from 0.788 − 0.882). ConclusionsThe interscan agreement of node volumes between SD and ULD is high depending on the choice of kernel and reconstruction algorithm. However, caution should be exercised when comparing two image series that were not identically reconstructed.

EFFICACY AND SAFETY OF RADIOFREQUENCY ABLATION VERSUS ETHANOL ABLATION

Objectives: Multinodular goiter is the most common thyroid disease in Mongolia. Recent guidelines suggest that a nodule without clinical symptoms should be treated with watchful waiting however, some patients require treatment because of cosmetic problems or symptoms. The main treatment remainssurgical resection, however, minimally invasive alternatives are being investigated. Ethanol ablation (EA), laser ablation, microwave ablation, and radiofrequency ablation (RFA) are safe and effective techniques for the treatment of nodular goiter. This retrospective review evaluates two widely used methods of ablation in Mongolia, ethanol ablation (EA) methods and RFA. Our objective is to compare volume reduction of single-session EA and RFA for thyroid nodules of different compositions and sizes. Materials and Methods: This retrospective study was approved by the Research Ethics Committee of the Mongolian National University of Medical Sciences and informed consent was obtained from all patients before EA and RFA. From January 2019 to January 2020, 50 patients with nodular goiter who underwent RFA (mean age 45.74 ±12.45 years) and 50 patients treated with sonography (US)-guided EA (mean age 36.52 ±9.61 years) were enrolled in this study. Nodules were assessed prior to treatment and at 1, 3, 6, and 12 months follow-up. Nodule volume, symptomatic and cosmetic assessmentscores were recorded at each time point. The primaryendpoint was the volume reduction ratio (percentage) at 1, 3, 6, and 12-month follow-ups. Secondary endpoints included therapeutic success rate, improvement of symptoms and cosmetic problems, and a number of major complications. Results: For the primary outcome of nodule volume reduction, in the RFA and EA groups, the absolute volume reductions at the 12-month follow-up were 62.8±13.2% (50) and 55.8±0.0% (n = 50) respectively. The treatment outcomes are summarized in Tables 3, 4, 5, and 6 and Figures 1, 2, 3, 4, 5, and 6. In RFA group, the mean volume reductions at the 1, 3, 6 and 12-month follow-ups were 33.0±11.0% (n = 50), 44.7± 17.0% (n = 50), 57.3± 14.7% (n = 50), and 62.8± 13.2% (n = 50), respectively. In EA group, the mean volume reductions at the 1, 3, 6 and 12-month follow-ups were 18.3±0.0% (n = 50), 30.5±0.0% (n = 50), 42.5±0.0% (n = 50), and 55.8±0.0% (n = 50), respectively. Conclusion: The purpose of this article is to review the current evidence relating to image-guided ablation of thyroid disease with a focus on clinical outcomes and complication rates for patients treated with this minimally invasive approach. EA may be appropriate as the first-line treatment modality for cystic thyroid nodules, which has comparable therapeutic efficacy to, but is less expensive than, RF ablation.

Radiofrequency Ablation of Indeterminate Thyroid Nodules: The First North American Comparative Analysis.

Thyroid nodules can be classified as benign, malignant, or indeterminate, the latter of which make up 10–30% of nodules. Radiofrequency ablation (RFA) has become an attractive and promising therapy for the treatment of benign thyroid nodules. However, few studies have investigated the safety and efficacy of RFA for the management of indeterminate thyroid nodules. In this study, 178 patients with thyroid nodules diagnosed as benign (Bethesda II) or indeterminate (Bethesda III/IV) by preoperative cytopathological analysis were included. Patients in the benign and indeterminate cohorts had similar thyroid nodule volume reduction rates at 65.60% and 64.20%, respectively (p = 0.68). The two groups had similar nodular regrowth rates, at 11.2% for benign nodules and 9.40% for indeterminate nodules (p = 0.72). A total of three cases of transient dysphonia were reported. RFA of indeterminate thyroid nodules was comparable to that of benign thyroid nodules in all parameters of interest, including volume reduction rate. To our best knowledge, our work is the first North American analysis comparing benign and indeterminate thyroid nodules and suggests RFA to be a promising modality for the management of indeterminate thyroid nodules.

Intra- and Inter-Reader Variations in Lung Nodule Measurements: Influences of Nodule Size, Location, and Observers.

(1) Background: Accurate measurement of lung-nodule size is necessary, but whether a three-dimensional volume measurement is better or more reliable than the one-dimensional method is still unclear. This study aimed to investigate the intra- and inter-reader variations according to nodule type, size, three-dimensional volume measurements, and one-dimensional linear measurements. (2) Methods: This retrospective study included computed tomography (CT) examinations of lung nodules and volume measurements performed from October to December 2016. Two radiologists independently performed all measurements. Intra-class correlation coefficients (ICC) and Bland-Altman plots were used for analysis. (3) Results: The overall variability in the calculated volume was larger than when using the semiautomatic volume measurement. Nodules <6 mm tended to have larger variability than nodules ≥6 mm in both one-dimensional and calculated volume measurements. The isolated type showed smaller variability in both intra- and inter-reader comparisons. The juxta-vascular type showed the largest variability in both one-dimensional and calculated volume measurements. The variability was decreased when using the 3D volume semiautomated software. (4) Conclusions: The present study suggests that 3D semiautomatic volume measurements showed lower variability than the calculated volume measurement. Nodule size and location influence measurement variability. The intra- and inter-reader variabilities in nodule volume measurement were considerable.

Efficacy and safety of ultrasound-guided microwave ablation versus surgical resection for Bethesda category IV thyroid nodules: A retrospective comparative study.

ObjectiveThe objective of this study was to assess the efficacy and safety of ultrasound-guided microwave ablation (MWA) for Bethesda IV thyroid nodules and to compare the outcomes, complications, and costs of MWA and thyroidectomy.MethodsA total of 130 patients with Bethesda IV nodules were retrospectively reviewed, involving 46 in the MWA group and 84 in the surgery group. The local institutional review board approved this study. Patients in the MWA group were followed up at 1, 3, 6, and 12 months after the intervention. Postoperative complications, treatment time, and cost in the two groups were compared.ResultsAmong 84 patients with 85 Bethesda IV nodules in the surgery group, postoperative pathology was benign lesions, borderline tumors, papillary thyroid carcinoma, follicular variant papillary thyroid carcinoma, follicular thyroid carcinoma, and medullary carcinoma in 44, 4, 27, 6, 3, and 1 cases, respectively. Malignant thyroid nodules were more prone to solid echostructure (86.11% vs. 72.72%), hypoechogenicity (55.56% vs. 13.63%), and irregular margin (47.22% vs. 13.63%) than benign lesions. The nodule volume reduction rate of patients at 12 months after MWA was 85.01% ± 10.86%. Recurrence and lymphatic and distant metastases were not reported during the follow-up period. The incidence of complications, treatment time, hospitalization time, incision length, and cost were significantly lower in the MWA group than in the surgery group (all p < 0.001).ConclusionsMWA significantly reduces the volume of Bethesda IV nodules with high safety and is recommended for those with surgical contraindications or those who refuse surgical resection. Patients with suspicious ultrasound features for malignancy should be actively treated with surgery.

Effects of Slow-Acting Metformin Treatment on the Hormonal and Morphological Thyroid Profile in Patients with Insulin Resistance.

Metformin appears to reduce TSH levels in untreated hypothyroid patients. In contrast, in euthyroid patients with type 2 diabetes mellitus (T2DM), metformin is initially devoid of effects on TSH. However, it is followed by a significant reduction in TSH level after twelve months of treatment. Additionally, some evidence suggests that metformin may also improve thyroid morphological abnormalities. This study aimed to evaluate the effects of metformin not only on TSH and thyroid hormone values, but also on thyroid volume and nodules. A total of 50 patients (mean age: 36.9 ± 12.8 years) with insulin resistance (homeostatic model assessment (HOMA) index ≥2.5) and with thyroid uninodular disease were recruited for this study. They were prescribed slow-acting metformin at a daily dose of 500 mg for six months. Treatment with metformin in euthyroid patients with uninodular thyroid disease and insulin resistance reduces TSH levels, increases FT4 and FT3 values, and decreases thyroid and nodule volumes. These data suggest that metformin may be an effective drug not only for the treatment of T2DM and metabolic syndrome, but also for thyroid disease.

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.

The value of ultrasound guided laser ablation in papillary thyroid recurrence carcinoma: A retrospective, single center study from China.

ObjectiveThe efficacy and safety of ultrasound-guided percutaneous laser ablation (PLA) for treating recurrent papillary thyroid cancer nodules (RPTCNs).MethodsA retrospective study was conducted in 43 patients with single recurrent thyroid cancer which was diagnosed by fine needle aspiration biopsy (FNAB). The extent of ablation was assessed by contrast-enhanced ultrasound (CEUS) 24h after PLA. At baseline (before ablation), 6, and 12 months, and every 6 months thereafter, the following were recorded: nodule maximum diameter, volume reduction rate (VRR), complications, and side effects.ResultAll 43 patients were successfully treated with PLA without serious complications. All patients underwent CEUS 24 hours after PLA treatment, and all achieved complete ablation. The success rate of single ablation was 100%. The average follow-up time was 23.47 ± 6.50 months, 12 ~ 36 months. At the last follow-up, 32 (74.4%) ablation lesions disappeared completely and 11 (25.6%) ablation lesions showed scar-like changes. No lymph node metastasis was found during follow-up. The maximum diameter and volume of nodules decreased from 5.1 ± 1.4 mm, 86.22 ± 20.46 mm3 before operation to 0.73 ± 1.1 mm, 1.02 ± 1.92 mm3 at the end of observation (P < 0.01). The average volume reduction rates (VRR) at 6, 12, 18, 24, 30 and 36 months after ablation were 11.92%, 60.64%, 82.26%, 90.96%, 93.7% and 97.79% respectively. No regrowth of treated nodule and distant metastases were detected. One patient (2.3%) had local recurrence and was treated with PLA again.ConclusionUltrasound-guided PLA appears to be effective and safe for treating unifocal RPTCNs in selected patients who are ineligible for surgery, which is suitable for clinical application and promotion.

Use of 3D ultrasound to characterise temporal changes in thyroid nodules: an in vitro study.

Thyroid nodules are extremely common, with prevalence rate up to 68%, yet only 7-15% of these are malignant. Many nodules require surveillance and 2-dimensional ultrasound (2D US) is used. Issues include the huge workload of obtaining and labeling images and difficulty comparing sizes of nodules over time due to large inter-operator variability. Inaccuracies may result in unnecessary FNAC or missed diagnosis of malignant nodules. We compared two techniques: freehand plain 2D US against freehand 2D US with gyroscopic guidance, both followed by 3D reconstruction using software. We measured the volume of nodules and a normal thyroid gland. We found 2D US with gyroscopic guidance to be superior to plain 2D US as 3D reconstructions of greater accuracy are produced. The volume of the thyroid lobe measured 8.42cm3 ± 0.94 was reasonably close to the normal average volume. However, the measured volume of the ellipsoidal nodule by the software is 8.69cm3 ± 0.97 while the measured volume of the spherical nodule is 7.09cm3 ± 0.79. As the expected volume of the nodules were 4.24cm3 and 4.19cm3 respectively, the measured volume of the nodule was not accurate. The time taken to characterise nodules was reduced greatly from over 30min in usual procedure to less than 10min. We find 3D US promising for evaluating size of thyroid nodules, with potential to study other TIRAD characteristics. Freehand 2D US with gyroscopic guidance shows the most promise for producing reliable, accurate and faster 3D reconstructions of thyroid nodules.

Variability of pulmonary nodule volumetry on coronary CT angiograms

This study aims to investigate the variability of pulmonary nodule (PN) volumetry on multiphase coronary CT angiograms (CCTA).Two radiologists reviewed 5973 CCTA scans in this cross-sectional study to detect incidental solid noncalcified PNs measuring between 5 and 8 mm. Each radiologist measured the nodules’ diameters and volume, in systole and diastole, using 2 commercially available software packages to analyze PNs.Bland-Altman analysis was applied between different observers, software packages, and cardiac phases. Bland-Altman subanalysis for the systolic and diastolic datasets were also performed.A total of 195 PNs were detected within the inclusion criteria and measured in systole and diastole. Bland-Altman analysis was used to test the variability of volumetry between cardiac phases ([−47.0%; 52.3%]), software packages ([−50.2%; 68.2%]), and observers ([−14.5%; 27.8%]). The inter-observer variability of the systolic and diastolic subsets was [−13.6%; 31.4%] and [−13.9%; 19.7%], respectively.Using diastolic volume measurements, the variability of PN volumetry on CCTA scans is similar to the reported variability of volumetry on low-dose CT scans. Therefore, growth estimation of PNs on CCTA scans could be feasible.

Dominant benign thyroid nodules (BTN) treated with percutaneous microwave termoablation (PMWT): an effective tool to decrease thyroid nodule volume

Dominant benign thyroid nodules (BTN) treated with percutaneous microwave termoablation (PMWT): an effective tool to decrease thyroid nodule volume

OA05.04 A Comparison of Stage- and Histology-Specific CT Sensitivity in the NELSON Trial and the NLST

The Dutch-Belgian lung cancer screening trial (Nederlands-Leuvens Longkanker Screenings Onderzoek [NELSON]) demonstrated a reduction in lung cancer mortality of 24%1 for screening with low-dose computed tomography (CT), compared to the 20%2 found in the National Lung Screening Trial (NLST). The NELSON and NLST differed in study population and trial design. Specifically, in contrast to the NLST, the NELSON trial employed a nodule management protocol that incorporated nodule volume and growth3 as opposed to nodule diameter only.

Ultrasound-guided microwave ablation combined with ethanol injection for the treatment of solitary nodular retrosternal goiter: a prospective study of 72 patients.

We prospectively evaluated the efficacy and safety of microwave ablation (MWA) combined with ethanol injection (EI) in solitary nodular retrosternal goiters (RSGs). From November 2018 to November 2020, 72 patients diagnosed with solitary nodular RSG were treated by ultrasound-guided MWA with EI. Patients were followed up at 1, 3, 6, and 12 months and every 6-12 months thereafter by ultrasound and contrast-enhanced ultrasound (CEUS). The nodule volume, volume reduction ratio (VRR), neck circumference, symptom score, and cosmetic grading score were recorded to evaluate the treatment efficacy. All patients successfully underwent treatment. The mean initial nodule volume was 71.25 mL ± 61.61 mL, which decreased significantly to 7.47 mL ± 9.19 mL at a mean follow-up time of 23.89 months ± 7.66 months (range 15-39 months) with a mean VRR of 90.99% ± 7.52%. The neck circumference, symptom score, and cosmetic grading score significantly decreased from 36.94 cm ± 3.04 cm to 35.06 cm± 2.84 cm, from 3.78 ± 1.19 to 0.36 ± 0.63, and from 3.42 ± 0.76 to 1.13 ± 0.37, at the 12 months after treatment, respectively (all 7 p < 0.001). Of all the nodules, eight (11.1%) received a second ablation. No major complications occurred. Ultrasound-guided MWA combined with EI is an effective and safe treatment for solitary nodular RSG and may be a potential alternative to surgery in selected patients, especially for those who are ineligible or unwilling to receive surgical treatment. • MWA combined with EI is an effective and safe approach for the treatment of solitary nodular RSG. • This treatment should be conducted by experienced physicians. • It provides a potential alternative to surgery for solitary nodular RSG in patients who are ineligible or unwilling to receive surgical treatment.

Deep Learning-Based CT Imaging in the Diagnosis of Treatment Effect of Pulmonary Nodules and Radiofrequency Ablation.

To study the effect of computerized tomography (CT) images based on deep learning algorithms on the diagnosis of pulmonary nodules and the effect of radiofrequency ablation (RFA), the U-shaped fully convolutional neural network (FCNN) (U-Net) was enhanced. The convolutional neural network (CNN) algorithm was compared with the U-Net algorithm, and segmentation performances were analyzed. Then, it was applied to the CT image diagnosis of 110 lung cancer patients admitted to hospital. The patients in the observation group (55 cases) were diagnosed based on the improved U-Net algorithm, while those in the control group (55 cases) were diagnosed by traditional methods and then treated with RFA. The Dice coefficient (0.8753) and intersection over union (IOU) (0.8788) obtained by the proposed algorithm were remarkably higher than the Dice coefficient (0.7212) and IOU (0.7231) obtained by the CNN algorithm, and the differences were considerable (P < 0.05). The boundary of the pulmonary nodule can be segmented more accurately by the proposed algorithm, which had the segmentation result closest to the gold standard among the three algorithms. The diagnostic accuracy of the pulmonary nodule in the observation group (95.3%) was superior to that of the control group (90.7%). The long diameter, volume, and maximum area of the pulmonary nodule of the observation group were significantly higher than those of the control group, with substantial differences (P < 0.05). Patients were reexamined after one, three, and six months of treatment, and 71 patients (64.55%) had complete remission, 32 patients (29.10%) had partial remission, 6 patients (5.45%) had stable disease, and 1 patient (0.90%) had disease progression. The remission rate (complete remission + partial remission) was 93.65%. The improved U-NET algorithm had good image segmentation performance and ideal segmentation effect. It can clearly display the shape of pulmonary nodules, locate the lesions, and accurately evaluate the therapeutic effect of RFA, which had clinical application value.

Different effects of intravenous and local anesthesia in patients undergoing ultrasound-guided radiofrequency ablation of thyroid nodules: a prospective cohort study

Purpose To compare the efficacy and safety of intravenous anesthesia (IV) with local anesthesia (LA) in patients undergoing ultrasound (US)-guided radiofrequency ablation (RFA) of thyroid nodules. Methods 50 patients with American Society of Anesthesiologists classification grades I–II undergoing US-guided thyroid RFA were enrolled and randomly (1:1) divided into IV (conscious sedation with Ramsay Sedation Scale [RSS] scores of 2–3 with an anesthesiologist) and LA (subcutaneous anesthesia with lidocaine without an anesthesiologist) groups. Pre-, intra- and post-procedural blood pressure (BP) (SBP0/DBP0, SBP1/DBP1, and SBP2/DBP2), intra- and post-procedural pain (NRS1 and NRS2), ablated area volume, treatment time and adverse events were analyzed and compared. Results Age, sex, weight, number, nature, volume of nodules, and SBP0/DBP0 showed no difference between both groups. 11 and 0 patients’ SBP1/DBP1 were elevated in the LA and IV groups. NRS1 differed between both groups. 6 patients in the LA group had moderate or severe pain, but none in the IV group. No between-group difference in SBP2/DBP2, NRS2, ablation completion rate and ablated volume was noted. The median procedure duration differed from 1109 (176) s in IV group and 723 (227) s in LA groups. There was no increased incidence of adverse events in IV group. Conclusions IV with RSS scores of 2–3 maintained intra-procedural BP and relieved intra-procedural pain better, without affecting the ablation efficacy and increasing complications. Despite increased treatment time, IV is a potential option for patients undergoing US-guided RFA of thyroid nodules.

Community structure of deep-sea benthic metazoan meiofauna in the polymetallic nodule fields in the eastern Clarion-Clipperton Fracture Zone, Pacific Ocean

The abyssal sea floor of the Clarion-Clipperton Fracture Zone (CCFZ) in the Pacific Ocean is expected to become a commercially important nodule mining area in the near future. Hence, it is crucial to understand the community structure of biological communities there, so that nodule harvesting activities can be designed to minimize deleterious impacts on marine life. Meiofauna is an important component of the abyssal infaunal community but relatively little is known on their biodiversity, abundance, and community structure in the CCFZ. We provide here the first quantitative observations of metazoan benthic animals ≥40 μm in a 30 × 30 km area survey stratum in the Ocean Mineral Singapore contract area at the eastern end of the CCFZ. A total of 88 867 individuals, identified to 23 animal groups, were collected from 12 randomly sampled stations using a multiple corer. Even in our small surveyed area, the meiofaunal community structure appeared different at our stations, confirming that the CCFZ deep sea floor is very diverse. From the top 0–5 cm sediment layer, unsurprisingly, the three most abundant animal groups were the Nematoda (87.9 ± 2.9%), the Nauplii (5.0 ± 1.3%) and the Copepoda (4.3 ± 1.1%). The majority of the meiobenthos (76.6%) were in the top 0–2 cm sediment layer. Our results suggested that substratum shear strength was negatively and significantly correlated to meiofaunal abundances among the 12 stations. Nodule cover and nodule volume did not appear to affect the meiofaunal community structure at the major taxon level. The mean meiofaunal abundance (235.7 ± 26.4 ind./10 cm2) was relatively high at our site in comparison with previous studies elsewhere in the CCFZ, further confirming the westward decrease in meiofaunal abundance across the CCFZ.

Efficacy and Safety of Radiofrequency Ablation of Thyroid Nodules: A Multi-institutional Prospective Cohort Study.

Radiofrequency ablation (RFA) has been recently adopted into the practice of thyroidology in the United States, although its use as an alternative to traditional thyroid surgery in Asia and Europe came near the turn of the 21st century. In the United States, only a few studies with small sample sizes have been published to date. We examined outcomes of benign thyroid nodules treated with RFA from 2 North American institutions. We performed a prospective, multi-institutional cohort study of thyroid nodules treated with RFA between July 2019 and January 2022. Demographics, sonographic characteristics of thyroid nodules, thyroid function profiles, procedural details, complications, and nodule volume measurements at 1, 3, 6, and 12 months follow-up were evaluated. Adjusted multivariate logistic regression analysis was performed to identify sonographic features associated with treatment failure. A total of 233 nodules were included. The median and interquartile range of volume reduction rate (VRR) at 1, 3, 6, and 12 months were 54% [interquartile range (IQR): 36%-73%], 58% (IQR: 37%-80%), 73% (IQR: 51%-90%), and 76% (IQR: 52%-90%), respectively ( P <0.001). Four patients presented with toxic adenomas. All patients were confirmed euthyroid at 3-month postprocedure follow-up. Two patients developed temporary hoarseness of voice, but no hematoma or nodular rupture occurred postprocedure. Elastography was significantly associated with VRR. Compared with soft nodules, stiff nodules were more likely to have a lower VRR (odds ratio: 11.64, 95% confidence interval: 3.81-35.53, P <0.05), and mixed elasticity was also more likely to have a lower VRR (odds ratio: 4.9; 95% confidence interval: 1.62-14.85, P <0.05). This is the largest multi-institutional North American study examining thyroid nodule treatment response to RFA. RFA is a safe and effective treatment option that allows preservation of thyroid function with minimal risk of procedural complications.