Machine Learning Prediction of Radiofrequency Thermal Ablation Efficacy: A New Option to Optimize Thyroid Nodule Selection.

BACKGROUND: Radiofrequency (RF) is a therapeutic modality for reducing the volume of large benign thyroid nodules. If thermal therapies are interpreted as an alternative strategy to surgery, critical issues in their use are represented by the extent of nodule reduction and by the durability of nodule reduction over a long period of time. OBJECTIVE: To assess the ability of machine learning to discriminate nodules with volume reduction rate (VRR) < or ≥50% at 12 months following RF treatment. METHODS: A machine learning model was trained with a dataset of 402 cytologically benign thyroid nodules subjected to RF at six Italian Institutions. The model was trained with the following variables: baseline nodule volume, echostructure, macrocalcalcifications, vascularity, and 12-month VRR. RESULTS: After training, the model could distinguish between nodules having VRR <50% from those having VRR ≥50% in 85% of cases (accuracy: 0.85; 95% confidence interval [CI]: 0.80-0.90; sensitivity: 0.70; 95% CI: 0.62-0.75; specificity: 0.99; 95% CI: 0.98-1.0; positive predictive value: 0.95; 95% CI: 0.92-0.98; negative predictive value: 0.95; 95% CI: 0.92-0.98). CONCLUSIONS: This study demonstrates that a machine learning model can reliably identify those nodules that will have VRR < or ≥50% at 12 months after one RF treatment session. Predicting which nodules will be poor or good responders represents valuable data that may help physicians and patients decide on the best treatment option between thermal ablation and surgery or in predicting if more than one session might be necessary to obtain a significant volume reduction.

Radiofrequency ablation for benign thyroid nodules according to different ultrasound features: an Italian multicentre prospective study.

Background The purpose of this study was to confirm the generalisation of radiofrequency ablation (RFA) in the treatment of benign thyroid nodules (BTN) and to look for a correlation between final shrinkage and some ultrasound (US) findings in a large Italian population data set. Methods This prospective study included 337 patients with solid cold BTN from six Italian institutions. Nodule volume, US pattern, thyroid function, symptom/cosmetic scores and complications were evaluated before treatment and at 6 and 12 months. The primary outcome was to find a correlation between basal volume and US pattern of the nodules and final shrinkage. The secondary outcome was to confirm the efficacy and safety of RFA in a large data set. Results The median basal volume was 20.7 mL, and this significantly decreased after RFA at 6 months (7.3 mL (-63.5%), P < 0.001) and at 12 months (6 mL (-70%), P vs 6 months = 0.009). A significant correlation was found for US structure (a spongiform pattern showing a 76% reduction vs 67 and 66% of mix and solid patterns respectively, P < 0.01) as well as for vascularity (intense peripheral and intranodal patterns showing 71 vs 68 and 67% of weak peripheral and intranodal and peripheral patterns respectively, P < 0.03), but not for macrocalcifications. A slight inverse correlation was found between nodule basal volume and shrinkage (Spearman: -0.23). Mean symptoms/cosmetic scores were significantly reduced. No major complications were encountered. Conclusions This multicentre study validated the efficacy and safety of RFA for treating BTN and showed a clear correlation between final shrinkage and some common US findings.

Virtual Autopsy as a Screening Test Before Traditional Autopsy: The Verona Experience on 25 Cases.

BACKGROUND: Interest has grown into the use of multidetector computed tomography (CT) and magnetic resonance imaging as an adjunct or alternative to the invasive autopsy. We sought to investigate these possibilities in postmortem CT scan using an innovative virtual autopsy approach. METHODS: Twenty-five postmortem cases were scanned with the Philips Brilliance CT-64 and then underwent traditional autopsy. The images were interpreted by two blinded forensic pathologists assisted by a radiologist with the INFOPSY® Digital Autopsy Software System which provides three-dimensional images in Digital Imaging and Communications in Medicine format. Diagnostic validity of virtual autopsy (accuracy rate, sensitivity, specificity, and predictive values) and concordance between the two forensic pathologists (kappa intraobserver coefficients) were determined. RESULTS: The causes of death at traditional autopsies were hemorrhage due to traumatic injuries (n = 8), respiratory failure (5), asphyxia due to drowning (4), asphyxia due to hanging or strangulation (2), heart failure (2), nontraumatic hemorrhage (1), and severe burns (1). In two cases, the cause of death could not be ascertained. In 15/23 (65%) cases, the cause of death diagnosed after virtual autopsy matched the diagnosis reported after traditional autopsy. In 8/23 cases (35%), traditional autopsy was necessary to establish the cause of death. Digital data provided relevant information for inferring both cause and manner of death in nine traumatic cases. The validity of virtual autopsy as a diagnostic tool was higher for traumatic deaths than other causes of death (accuracy 84%, sensitivity 82%, and specificity 86%). The concordance between the two forensic pathologists was almost perfect (>0.80). CONCLUSIONS: Our experience supports the use of virtual autopsy in postmortem investigations as an alternative diagnostic practice and does suggest a potential role as a screening test among traumatic deaths.

Surgical excision of developmental retrorectal cysts: results with long-term follow-up from a single institution.

Developmental cysts are very rare lesions occurring in the retrorectal space, and include epidermoid, dermoid, tailgut cysts and teratomas. There is little information on their natural history and biologic behavior, although a recent paper reported a greater incidence of malignant transformation than previously thought. The diagnosis requires high-resolution imaging, and complete surgical excision is the treatment of choice. In this paper we analyzed short- and long-term results of surgical excision of six retrorectal developmental cysts observed at our institution over a period of 11 years. All patients were women, three were referred with an infected perineal fistula/pelvic abscess after having undergone drainage surgery elsewhere. In these three patients, excision was attempted through a trans-perineal approach, which was technically demanding and ultimately incomplete because of the intense surrounding inflammation. Multiple re-interventions were required for tumor recurrence, and two of them still present an occasional perineal discharge. In the other three patients, a trans-perineal or trans-anal route was employed according to tumor location, without any recurrence at a median follow-up of 118.5 months. Final pathologic diagnosis included five tailgut cysts and one teratoma. This paper shows that the treatment of developmental cysts may be very challenging, especially when they are associated with a concomitant fistula/abscess and are not correctly diagnosed at presentation. In our experience, healing was finally achieved in four patients out of six. All the lesions were benign, and no malignant transformation was observed during follow-up, even in tumors partially resected.

Standard sonography and arthrosonography in the study of rotator cuff tears.

PURPOSE: The aim of this study was to evaluate the sensitivity of ultrasonography, integrating standard ultrasound and arthrosonography after injecting a saline solution into the glenohumeral cavity in cases of suspected rotator cuff tears. MATERIALS AND METHODS: We prospectively examined 40 patients awaiting shoulder arthroscopy for suspected or diagnosed tears of the rotator cuff. A radiologist, unaware of the pre-operative diagnosis, performed an ultrasound scan on all the patients before and after the injection of saline solution into the glenohumeral cavity. The parameters considered were presence or absence of a rotator cuff injury; type of injury according to Snyder and its extent along the longitudinal and transverse planes; presence or absence of effusion into the articular cavity; subacromial/subdeltoid bursal distension. All the patients underwent arthroscopy either the same day or the day after the ultrasound examination. RESULTS: Standard sonography showed 26 complete rotator cuff tears (type C according to Snyder), 2 partial tears (type B according to Snyder) and 12 intact rotator cuffs. Arthrosonography detected 31 complete rotator cuff tears (type C according to Snyder), 1 partial tear (type B according to Snyder) and 8 intact rotator cuffs.Arthroscopy identified 32 complete rotator cuff tears (type C according to Snyder), 1 partial tear (type B according to Snyder) and 8 intact rotator cuffs. Analysis of the results shows that, taking arthroscopy as the gold standard, the sensitivity of normal sonography is 81.2%, whereas that of arthrosonography is 96.8% (p < 0.05). CONCLUSIONS: On the basis of the data obtained in this study, standard sonography, integrated with the injection of a saline solution into the glenohumeral cavity, considerably increases the diagnostic sensitivity for rotator cuff tears. The authors suggest that arthrosonography can be used in the event of suspected rotator cuff tears, when MRI is contraindicated.