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Patients often opt for implantation of testicular prostheses following orchidectomy for cancer or torsion. Recipients of testicular prostheses report issues regarding firmness, shape, size, and position, aspects of which relate to current limitations of silicone materials used and manufacturing methods for soft prostheses. We aim to create a 3D printable testicular prosthesis which mimics the natural shape and stiffness of a human testicle using a lattice infill structure. Porous testicular prostheses were engineered with relative densities from 0.1 to 0.9 using a repeating cubic unit cell lattice inside an anatomically accurate testicle 3D model. These models were printed using a multi-jetting process with an elastomeric material and compared with current market prostheses using shore hardness tests. Additionally, standard sized porous specimens were printed for compression testing to verify and match the stiffness to human testicle elastic modulus (E-modulus) values from literature. The resulting 3D printed testicular prosthesis of relative density between 0.3 and 0.4 successfully achieved a reduction of its bulk compressive E-modulus from 360 KPa to a human testicle at 28 Kpa. Additionally, this is the first study to quantitatively show that current commercial testicular prostheses are too firm compared to native tissue. 3D printing allows us to create metamaterials that match the properties of human tissue to create customisable patient specific prostheses. This method expands the use cases for existing biomaterials by tuning their properties and could be applied to other implants mimicking native tissues., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Skewes, Chen, Forrestal, Rukin and Woodruff.)

Small renal masses are commonly diagnosed with modern medical imaging. Renal tumour volume has been explored as a prognostic tool to help decide when intervention is needed and appears to provide additional prognostic information for smaller tumours compared with tumour diameter. However, the current method of calculating tumour volume in clinical practice uses the ellipsoid equation (π/6 × length × width × height) which is an oversimplified approach. Some research groups trace the contour of the tumour in every image slice which is impractical for clinical use. In this study, we demonstrate a method of using 3D segmentation software and the 3D interpolation method to rapidly calculate renal tumour volume in under a minute. Using this method in 27 patients that underwent radical or partial nephrectomy, we found a 10.07% mean absolute difference compared with the traditional ellipsoid method. Our segmentation volume was closer to the calculated histopathological tumour volume than the traditional method (p = 0.03) with higher Lin's concordance correlation coefficient (0.79 vs 0.72). 3D segmentation has many uses related to 3D printing and modelling and is becoming increasingly common. Calculation of tumour volume is one additional benefit it provides. Further studies on the association between segmented tumour volume and prognosis are needed., (© 2021. Society for Imaging Informatics in Medicine.)

Background: There is increasing research in using segmentation of prostate cancer to create a digital 3D model from magnetic resonance imaging (MRI) scans for purposes of education or surgical planning. However, the variation in segmentation of prostate cancer among users and potential inaccuracy has not been studied., Methods: Four consultant radiologists, four consultant urologists, four urology trainees, and four nonclinician segmentation scientists were asked to segment a single slice of a lateral T3 prostate tumor on MRI ("Prostate 1"), an anterior zone prostate tumor MRI ("Prostate 2"), and a kidney tumor computed tomography (CT) scan ("Kidney"). Time taken and self-rated subjective accuracy out of a maximum score of 10 were recorded. Root mean square error, Dice coefficient, Matthews correlation coefficient, Jaccard index, specificity, and sensitivity were calculated using the radiologists as the ground truth., Results: There was high variance among the radiologists in segmentation of Prostate 1 and 2 tumors with mean Dice coefficients of 0.81 and 0.58, respectively, compared to 0.96 for the kidney tumor. Urologists and urology trainees had similar accuracy, while nonclinicians had the lowest accuracy scores for Prostate 1 and 2 tumors (0.60 and 0.47) but similar for kidney tumor (0.95). Mean sensitivity in Prostate 1 (0.63) and Prostate 2 (0.61) was lower than specificity (0.92 and 0.93) suggesting under-segmentation of tumors in the non-radiologist groups. Participants spent less time on the kidney tumor segmentation and self-rated accuracy was higher than both prostate tumors., Conclusion: Segmentation of prostate cancers is more difficult than other anatomy such as kidney tumors. Less experienced participants appear to under-segment models and underestimate the size of prostate tumors. Segmentation of prostate cancer is highly variable even among radiologists, and 3D modeling for clinical use must be performed with caution. Further work to develop a methodology to maximize segmentation accuracy is needed., (© 2020 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.)

Background: Three-dimensional (3D) printing is a promising technology, but the limitations are often poorly understood. We compare different 3D printing methods with conventional machining techniques in manufacturing meatal urethral dilators which were recently removed from the Australian market., Methods: A prototype dilator was 3D printed vertically orientated on a low-cost fused deposition modelling (FDM) 3D printer in polylactic acid (PLA) and acrylonitrile butadiene styrene (ABS). It was also 3D printed horizontally orientated in ABS on a high-end FDM 3D printer with soluble support material, as well as on an SLS 3D printer in medical nylon. The dilator was also machined in stainless steel using a lathe. All dilators were tested mechanically in a custom rig by hanging calibrated weights from the handle until the dilator snapped., Results: The horizontally printed ABS dilator experienced failure at a greater load than the vertically printed PLA and ABS dilators, respectively (503 g vs 283 g vs 163 g, p < 0.001). The SLS nylon dilator and machined steel dilator did not fail. The steel dilator is the most expensive with a quantity of five at 98 USD each, but this decreases to 30 USD each for a quantity of 1000. In contrast, the cost for the SLS dilator is 33 USD each for five and 27 USD each for 1000., Conclusions: Low-cost FDM 3D printing is not a replacement for conventional manufacturing. 3D printing is best used for patient-specific parts, prototyping or manufacturing complex parts that have additional functionality that cannot otherwise be achieved.

Three-dimensional (3D) printed prostate cancer models are an emerging adjunct for urological surgical planning and patient education, however published methods are costly which limits their translation into clinical practice. Multi-colour extrusion fused deposition modelling (FDM) can be used to create 3D prostate cancer models of a quality comparable to more expensive techniques at a fraction of the cost. Three different 3D printing methods were used to create the same 3D prostate model: FDM, colour jet printing (CJP) and material jetting (MJ), with a calculated cost per model of USD 20, USD 200 and USD 250 respectively. When taking into account the cost, the FDM prostate models are the most preferred 3D printing method by surgeons. This method could be used to manufacture low-cost 3D printed models across other medical disciplines.

Our "tips and tricks" focuses on all aspects of upper tract endourology and we hope these will be of use to all trainees and consultants who perform ureteroscopy. We report an "expert consensus view" from experienced endourological surgeons, on all aspects of advanced ureteroscopic techniques, with a particular focus on avoiding and getting out of trouble while performing ureteroscopy. In this paper we provide a summary of placing ureteric access sheath, flexible ureteroscopy, intra renal stone fragmentation and retrieval, maintaining visual clarity and biopsy of ureteric and pelvicalyceal tumours.

Purpose: Orchalgia is a common problem with varicoceles however the association between varicocele embolisation for the treatment of varicocele related pain has not been widely investigated. We aim to investigate the effectiveness of varicocele embolisation for the treatment of orchalgia secondary to varicoceles; and to see if pre-embolisation pain scores can be used to predict treatment outcomes., Methods: A prospectively collected database of patients undergoing varicocele embolisation for pain was analysed over a 10-year period. Pain scores were assessed with a 10-point visual analogue score. Analgesia requirements and satisfaction scores were assessed with questionnaires., Results: Total of 96 cases. Median age was 34 years old. Median pain scores reduced significantly following embolisation (p < 0.001). 74% had reduced pain (30% of these had resolution of pain), 24% had no change in symptoms and 1% had worsening pain. Those with moderate or severe pain had a reduction of pain in 81 and 79% of cases respectively, however 64% of cases with mild pain did not experience any benefit. We also noted a reduction in analgesia requirements and a median satisfaction score of 8/10., Conclusion: Primary varicocele embolisation can successfully reduce varicocele related orchalgia. It works best in those with moderate or severe pain. The majority of patients with mild pain may not experience any benefit so should be counseled appropriately. The classification of patients into those with mild, moderate or severe symptoms prior to embolisation should be done, so robust consenting can be performed.

Ureteroscopy is fast becoming the first line treatment option for the majority of urinary tract stones. Ureteroscopy training can be performed in a variety of ways including simulation, hands on ureteroscopy courses and supervised operative experience. We report an "expert consensus view" from experienced endourological surgeons, on all aspects of basic ureteroscopic techniques, with a particular focus on avoiding and getting out of trouble while performing ureteroscopy. In this paper we provide a summary of treatment planning, positioning, cannulation of ureteric orifice, guidewire placement, rigid ureteroscopy and stone fragmentation.

Urolithaisis is becoming an ever increasing urological, nephrological and primary care problem. With a lifetime prevalence approaching 10% and increasing morbidity due to stone disease, the role of ureteroscopy and stone removal is becoming more important. We discuss the current status of stone disease and review the ever increasing role that ureteroscopy has to play in its management. We discuss technological advances that have been made in stone management and give you an overview of when, how and why ureteroscopy is the most common treatment option for stone management. We touch on the role of robotic ureteroscopy and the future of ureteroscopy in the next 10 years.

Ultraviolet radiation exposure increases basal cell carcinoma (BCC) risk, but may be protective against prostate cancer. We attempted to identify exposure patterns that confer reduced prostate cancer risk without increasing that of BCC. We used a questionnaire to assess exposure in 528 prostate cancer patients and 442 men with basal cell carcinoma, using 365 benign prostatic hypertrophy patients as controls. Skin type 1 (odds ratio (OR)=0.47, 95% CI=0.26-0.86), childhood sunburning (OR=0.38, 95% CI=0.26-0.57), occasional/frequent sunbathing (OR=0.21, 95% CI=0.14-0.31), lifetime weekday (OR=0.85, 95% CI=0.80-0.91) and weekend exposure (OR=0.79, 95% CI=0.73-0.86) were associated with reduced prostate cancer risk. Skin type 1 (OR=4.00, 95% CI=2.16-7.41), childhood sunburning (OR=1.91, 95% CI=1.36-2.68), regular foreign holidays (OR=6.91, 95% CI=5.00-9.55) and weekend (OR=1.17, 95% CI=1.08-1.27) but not weekday exposure were linked with increased BCC risk. Combinations of one or two parameters were associated with a progressive decrease in the ORs for prostate cancer risk (OR=0.54-0.25) with correspondingly increased BCC risk (OR=1.60-2.54). Our data do not define exposure patterns that reduce prostate cancer risk without increasing BCC risk.