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Purpose This study is aimed to implement and validate a free Monte Carlo system (GMctdospp) for dose calculation in CT scans. Methods GMctdospp is an open source software developed by Institute of Medical Physics and Radiation Protection [1] . It can be downloaded and installed on a local server, to perform dosimetric calculations from CT images. Model of the CT equipment used for measurements (Siemens Somatom Definition AS) was provided within the software. The CT number to density calibration curve was introduced in the configuration data, to accurately match the HU ranges of simulated materials. Dose values at center and peripheral positions of a CTDI head phantom were measured with a pencil ionization chamber for different beam collimations (5 mm–10 mm–14.4 mm–19.2 mm), and compared to those simulated by the MC software. To define volumes for dose calculation, VOIs were obtained in the CT images by contouring the sensitive volume of the detector. In order to provide an estimation for skin dose, a second set of measurements was performed by scanning the head of a Rando phantom with gafchromic films placed on its surface in different positions (nose, occipital zone, temporal left and right). Images were acquired with a standard helical head routine protocol (120 kV, 19.2 mm collimation) and fixed tube current (200 mA). Dose values measured by the gafchromic films were then compared to those resulting from MC simulations based on the acquired CT images. Results The accuracy of the MC simulated dose values was variable. For CTDI head phantom, the difference between measured and simulated dose ranged between 2% and 19%. For skin dose an average agreement of about 13% was found between measured and calculated values. Conclusions Gmctdospp free MC software can be effectively used to calculate absorbed dose in CT scans acquired with fixed mA. Given the variability we observed in accuracy of the simulated dose values, further work is required in our institution, in order to validate the MC software. [ABSTRACT FROM AUTHOR]

The Funding section now reads: "This work received 'Ricerca Corrente 2023' funding from the Italian Ministry of Health to cover publication costs." Correction to: I Scientific Reports i https://doi.org/10.1038/s41598-022-18085-z, published online 19 August 2022 The Funding section in the original version of this Article was omitted. [Extracted from the article]

Aim: To study the feasibility of radiomic analysis of baseline [18F]fluoromethylcholine positron emission tomography/computed tomography (PET/CT) for the prediction of biochemical recurrence (BCR) in a cohort of intermediate and high-risk prostate cancer (PCa) patients. Material and methods: Seventy-four patients were prospectively collected. We analyzed three prostate gland (PG) segmentations (i.e., PGwhole: whole PG; PG41%: prostate having standardized uptake value – SUV > 0.41*SUVmax; PG2.5: prostate having SUV > 2.5) together with three SUV discretization steps (i.e., 0.2, 0.4, and 0.6). For each segmentation/discretization step, we trained a logistic regression model to predict BCR using radiomic and/or clinical features. Results: The median baseline prostate-specific antigen was 11 ng/mL, the Gleason score was > 7 for 54% of patients, and the clinical stage was T1/T2 for 89% and T3 for 9% of patients. The baseline clinical model achieved an area under the receiver operating characteristic curve (AUC) of 0.73. Performances improved when clinical data were combined with radiomic features, in particular for PG2.5 and 0.4 discretization, for which the median test AUC was 0.78. Conclusion: Radiomics reinforces clinical parameters in predicting BCR in intermediate and high-risk PCa patients. These first data strongly encourage further investigations on the use of radiomic analysis to identify patients at risk of BCR. Clinical relevance statement: The application of AI combined with radiomic analysis of [18F]fluoromethylcholine PET/CT images has proven to be a promising tool to stratify patients with intermediate or high-risk PCa in order to predict biochemical recurrence and tailor the best treatment options. Key Points: • Stratification of patients with intermediate and high-risk prostate cancer at risk of biochemical recurrence before initial treatment would help determine the optimal curative strategy. • Artificial intelligence combined with radiomic analysis of [18F]fluorocholine PET/CT images allows prediction of biochemical recurrence, especially when radiomic features are complemented with patients' clinical information (highest median AUC of 0.78). • Radiomics reinforces the information of conventional clinical parameters (i.e., Gleason score and initial prostate-specific antigen level) in predicting biochemical recurrence. [ABSTRACT FROM AUTHOR]

Lung cancer represents the second most common malignancy worldwide and lymph node (LN) involvement serves as a crucial prognostic factor for tailoring treatment approaches. Invasive methods, such as mediastinoscopy and endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA), are employed for preoperative LN staging. Among the preoperative non-invasive diagnostic methods, computed tomography (CT) and, recently, positron emission tomography (PET)/CT with fluorine-18-fludeoxyglucose ([18F]FDG) are routinely recommended by several guidelines; however, they can both miss pathologically proven LN metastases, with an incidence up to 26% for patients staged with [18F]FDG PET/CT. These undetected metastases, known as occult LN metastases (OLMs), are usually cases of micro-metastasis or small LN metastasis (shortest radius below 10 mm). Hence, it is crucial to find novel approaches to increase their discovery rate. Radiomics is an emerging field that seeks to uncover and quantify the concealed information present in biomedical images by utilising machine or deep learning approaches. The extracted features can be integrated into predictive models, as numerous reports have emphasised their usefulness in the staging of lung cancer. However, there is a paucity of studies examining the detection of OLMs using quantitative features derived from images. Hence, the objective of this review was to investigate the potential application of PET- and/or CT-derived quantitative radiomic features for the identification of OLMs. [ABSTRACT FROM AUTHOR]

Purpose: This study presents patient-specific quality assurance (QA) results from the first 395 clinical cases for the new helical TomoTherapy® platform (Radixact) coupled with dedicated Precision TPS.Methods: The passing rate of the Gamma Index (GP%) of 395 helical QA of patient-specific tomotherapy, acquired with ArcCHECK, is presented, analysed and correlated to various parameters of the plan. Following TG-218 recommendations, the clinic specific action limit (ALcs) and tolerance limit (TLcs) were calculated for our clinic and monitored during the analysed period.Results: The mean values ​​(± 1 standard deviation) of GP% (3%/2 mm) (both global and local normalization) are: 97.6% and 90.9%, respectively. The proposed ALcs and TLcs, after a period of two years' process monitoring are 89.4% and 91.1% respectively.Conclusions: The phantom measurements closely match the planned dose distributions, demonstrating that the calculation accuracy of the new Precision TPS and the delivery accuracy of the Radixact unit are adequate, with respect to international guidelines and reports. Furthermore, a first correlation with the planning parameters was made. Action and tolerance limits have been set for the new Radixact Linac. [ABSTRACT FROM AUTHOR]

We present a novel application of Tensor Network methods in cancer treatment as a potential tool to solve the dose optimization problem in radiotherapy. In particular, the intensity-modulated radiation therapy technique—that allows treating irregular and inhomogeneous tumors while reducing the radiation toxicity on healthy organs—is based on the optimization problem of the beamlets intensities that shall result in a maximal delivery of the therapy dose to cancer while avoiding the organs at risk of being damaged by the radiation. The resulting optimization problem is expressed as a cost function to be optimized. Here, we map the cost function into an Ising-like Hamiltonian, describing a system of long-range interacting qubits. Finally, we solve the dose optimization problem by finding the ground-state of the Hamiltonian using a Tree Tensor Network algorithm. In particular, we present an anatomical scenario exemplifying a prostate cancer treatment. A similar approach can be applied to future hybrid classical–quantum algorithms, paving the way for the use of quantum technologies in future medical treatments. [ABSTRACT FROM AUTHOR]

• Dysgeusia is a common side effect of radiotherapy for head & neck cancers. • Dosiomics and AI are applied for the first time to predict dysgeusia. • The central and anterior ⅔ regions of the tongue are associated with acute dysgeusia. • Dosiomics is comparable to conventional mean dose-based prediction of acute dysgeusia. • Dosiomics is superior to conventional mean dose-based prediction of chronic dysgeusia. To investigate the potential of dosiomics in predicting radiotherapy-induced taste distortion (dysgeusia) in head & neck (H&N) cancer. A cohort of 80 H&N cancer patients treated with radical or adjuvant radiotherapy and with a follow-up of at least 24 months was enrolled. Treatment information, as well as tobacco and alcohol consumption were also collected. The whole tongue was manually delineated on the planning CT and mapped to the dose map retrieved from the treatment planning system. For every patient, 6 regions of the tongue were examined; for each of them, 145 dosiomic features were extracted from the dose map and fed to a logistic regression model to predict the grade of dysgeusia at follow-up, with and without including clinical features. A mean dose-based model was considered for reference. Both dosiomics and mean dose models achieved good prediction performance for acute dysgeusia with AUC up to 0.88. For the dosiomic model, the central and anterior ⅔ regions of the tongue were the most predictive. For all models, a gradual reduction in the performance was observed at later times for chronic dysgeusia prediction, with higher values for dosiomics. The inclusion of smoke and alcohol habits did not improve model performances. The dosiomic analysis of the dose to the tongue identified features able to predict acute dysgeusia. Dosiomics resulted superior to the conventional mean dose-based model for chronic dysgeusia prediction. Larger, prospective studies are needed to support these results before integrating dosiomics in radiotherapy planning. [ABSTRACT FROM AUTHOR]

To establish size-dependent DRL and to estimate the effectiveness of the size-dependent DRLs over size-independent DRLs for a CT exposure optimization process. The study included 16,933 adult CT body examinations of the most common CT protocols. Acquisitions were included following an image quality assessment. Patients were grouped into five different classes by means of the water equivalent diameter (D w): 21 ≤ D w < 25, 25 ≤ D w < 29, 29 ≤ D w < 33,33 ≤ D w < 37 (in cm). CTDI vol , DLP, DLP tot. and SSDE median values were provided both for the sample as a whole (size-independent approach) and for each D w class (size-dependent approach). The performance of the two approaches in classifying sub-optimal examinations was evaluated through the confusion matrix and Matthews Correlation Coefficient (MCC) metric. The 75th percentile of the CTDI vol distribution was arbitrarily chosen as a threshold level above which the acquisitions are considered sub-optimal. CTDI vol , DLP, DLP tot and SSDE typical values (median values) are statistically different across D w groups. The confusion matrix analysis suggests that size-independent DRL could not mark potential suboptimal protocols for small and large patients. The agreement between the size-dependent and size-independent methods is strong only for the most populous classes (MCC > 0.7). For small and large patients size-independent approach fails to identify as sub-optimal around 20 % of the acquisition (MCC≪0.2). It was proven by means of the confusion matrix and MCC metric that stratifying DRLs by patient size, size-dependent DRL can be a powerful strategy in order to improve the dose optimization process shown that a size-independent DRL fails to identify sub-optimal examinations for small and large patients. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study is to assess if low-level laser therapy (LLLT) alleviates pain after the placement of orthodontic alignment archwire and if there could be a specific indication for the usage of LLLT according to the amount of dental crowding., Materials and Methods: Ninety subjects were included and randomly assigned to the tested group (orthodontic treatment and LLLT), placebo group (orthodontic treatment and simulated LLLT), and control group (orthodontic treatment only). Inclusion criteria are age between 13 and 30 years, completely erupted mandibular teeth, and lower crowding of ≥3 mm. Exclusion criteria are spaces or diastema in the lower arch, ectopic teeth, treatment plan including extractions or the use of auxiliary devices, and previous orthodontic treatment. Patients reported the pain experienced by using a numeric rating scale, ranging from 0 to 10, at specific time intervals, that is, 2 hours, 6 hours, 24 hours, and from day 2 to 7. Kruskal-Wallis H Test was used to assess differences in the maximum pain and pain experienced at each time interval among the three groups and in the maximum pain reported among subjects with different degree of crowding., Results: The final sample consisted of 84 patients, 41 male and 43 female patients, with a mean age of 16.5 ± 2.8 years. The pain experienced at each time interval and the maximum pain score were significantly lower in the tested group, whereas no differences were found between control and placebo groups. Moreover, no differences were found in the pain experienced among subjects with mild, moderate, and severe incisor crowding in all groups., Conclusions: LLLT is effective in alleviating the intensity and duration of pain experienced by patients after the engagement of alignment archwire. However, there is no specific indication for the usage of LLLT according to the amount of crowding., (Copyright © 2018 Elsevier Inc. All rights reserved.)

In periodontology, lasers have been suggested for the photodynamic therapy (PDT). Such therapy can be defined as the inactivation of cells, microorganisms or molecules induced by light and not by heat. The aim of our study is to assess the effect of Oxygen high-level laser therapy (OHLLT) in removing all bacterial deposits on root or implant surface by means of mechanical instrumentation and laser irradiation. OHLLT has two effects on targeted bacteria and tissues, decontamination and biostimulation. A total of 33 patients were randomly selected with a diagnosis of chronic periodontitis. The patients enrolled were 16 females and 17 males, six smokers and 4 diabetic patients. For each patient a periodontal charting was performed, assessing probing depth, plaque index and bleeding on probing at baseline and after 6 months. Microbiological analysis were performed with PCR Real Time, using paper tips to withdraw gingival fluid in periodontal pockets before and after treatment, at baseline and after 6 months. All patients were treated with OHLLT at baseline, after 1 week, after 2 weeks and every month for 6 months. After 6 months, all periodontal pockets were treated successfully, without complications and no significant differences in results. All clinical parameters showed an improvement, with a decrease both of plaque index (average decrease of 75%), bleeding on probing (average decrease of 62%) and probing depth (average decrease of 1.8 mm). After the treatment, a remarkable decrease in bacteria amount, both for each species and for total bacteria was observed except for Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis demonstrating that this laser protocol is effective on periodontitis treatment. OHLLT is efficient in treatment of chronic periodontitis as demonstrated by clinical and microbiological parameters, going beyond the traditional periodontal therapy.

Gingival augmentation techniques proposed in the international literature do not exclude a surgical component, which determines consequent post-surgical discomfort and results are not always predictable. In recent years, the introduction of laser biostimulation has led to a less invasive approach, particularly in the treatment of periodontally compromised patients, limiting the surgical phase to seriously compromised cases, with regeneration techniques for the restoration of a correct periodontal tissue anatomy. The aim of this in vitro study is to establish the validity of laser biostimulation in order to develop the epithelial keratinized layer of the tissue by stimulating fibroblasts-keratinocytes organotypic cultures and fibroblasts and keratinocytes mono-cultures. We created two groups (test and control), each one composed of 3 fibroblast cultures, 3 keratinocyte cultures and 3 organotypic cultures. We performed laser irradiation of test group with Wiser Doctor Smile Lambda, Flat Top Handpiece, at 50 J/cm2 of fluency with one application every 40 h for a total of 5 applications. Forty-eight h after the last laser application, we investigated the presence and amount of keratins 5 and 8 with citofluorymetric and western blotting analyses. Analyses showed an increase in keratin synthesis in test group cultures, showing a remarkable increase in production of keratin 8 in co-cultures test. Laser biostimulation can considerably enhance keratin synthesis when applied with high energy doses and repeated applications to keratinocytes-fibroblasts co-cultures.

The solitary fibrous tumours (SFT) are rare spindle cell neoplasms which generally originate from the pleura; also described are cases of SFT in other locations, included the genital-urinary tract. Described in the ambit the kidney are 19 cases of SFT and such rarity of localisation makes rather unknown the histogenesis and the prognosis of the lesion. We report the case of a 72 year old lady who attended our Unit for a mass which was clinically palpable at the level of the left hemiabdomen. Following an abdominal ultrasound scan a neoformation was highlighted which a successive tomodensitographic test indicated as being of likely pertinence of the middle third of the left kidney; the mass had a diameter of approximately 19 cm. A radical nephrectomy has been conducted. The histological examen highlighted a solitary fibrous tumour: the presence of hypercellularity, of cellular pleiomorphism and of a high number of mitosis has led to a histopathological diagnosis of malignancy of the neoplasm under examination. Departing from this case a review of the literature is carried out. The SFT of the kidney can have an aggressive character and more the present has hystopathological characters and clinical results are still rather unknown.

Background: The exact percentage of sexual dysfunctions resulting from Peyronie's disease remains very difficult to evaluate even today. The purpose of the present paper is to examine the series observed in our Department in order to make an assessment of the erectile function of patients found to be suffering from Peyronie's disease., Methods: Over the course of 9 years, 132 patients have come to our observation; they were originally examined for sexual function disturbances or for other pathologies of a uro-andrological nature., Results: In all, a total of 208 lesions were observed. Only 21 patients (22.5%) were found to be completely asymptomatic at the time of diagnosis. The most frequent symptom was shaft curvature (alone or in association with pain: 47%). The most commonly observed site for plaques was the back of the corpus cavernosum (43%). Impotentia erigendi was observed in 29 patients (22%) whereas impotentia coeundi was found in 50 (38). The functionally most significant lesions were those affecting the septum or in some way involved with the septum: 19 of 29 patients with impotentia erigendi presented such lesions., Conclusions: Considering the generally progressive course of the disease, the therapeutic approach taken by our Department is to fit a prosthesis to patients who have been suffering from Peyronie's disease for at least six months; conservative therapy is only undertaken in the rare cases of patients who have a perfectly preserved erection but who suffer from impotentia coeundi (as a result of curvature or pain).