Recent Publications by CFE Educators

OBJECTIVE

The aim of this study was to develop and evaluate the performance of artificial intelligence (AI) models that can identify safe and dangerous zones of dissection, and anatomical landmarks during laparoscopic cholecystectomy (LC).

SUMMARY BACKGROUND DATA

Many adverse events during surgery occur due to errors in visual perception and judgment leading to misinterpretation of anatomy. Deep learning, a subfield of AI, can potentially be used to provide real-time guidance intraoperatively.

METHODS

Deep learning models were developed and trained to identify safe (Go) and dangerous (No-Go) zones of dissection, liver, gallbladder, and hepatocystic triangle during LC. Annotations were performed by 4 high-volume surgeons. AI predictions were evaluated using 10-fold cross-validation against annotations by expert surgeons. Primary outcomes were intersection- over-union (IOU) and F1 score (validated spatial correlation indices), and secondary outcomes were pixel-wise accuracy, sensitivity, specificity, ± standard deviation.

RESULTS

AI models were trained on 2627 random frames from 290 LC videos, procured from 37 countries, 136 institutions, and 153 surgeons. Mean IOU, F1 score, accuracy, sensitivity, and specificity for the AI to identify Go zones were 0.53 (±0.24), 0.70 (±0.28), 0.94 (±0.05), 0.69 (±0.20). and 0.94 (±0.03), respectively. For No-Go zones, these metrics were 0.71 (±0.29), 0.83 (±0.31), 0.95 (±0.06), 0.80 (±0.21), and 0.98 (±0.05), respectively. Mean IOU for identification of the liver, gallbladder, and hepatocystic triangle were: 0.86 (±0.12), 0.72 (±0.19), and 0.65 (±0.22), respectively.

CONCLUSIONS

AI can be used to identify anatomy within the surgical field. This technology may eventually be used to provide real-time guidance and minimize the risk of adverse events.

BACKGROUND & AIMS

It has been suggested that patients with hepatocellular carcinoma (HCC) at high risk of wait-list dropout would have done poorly after liver transplantation (LT) because of tumour aggressiveness. To test this hypothesis, we analysed risk of wait-list dropout among patients with HCC in long-wait regions (LWRs) to create a dropout risk score, and applied this score in short (SWRs) and mid-wait regions (MWRs) to evaluate post-LT outcomes. We sought to identify a threshold in dropout risk that predicts worse post-LT outcome.

METHODS

Using the United Network for Organ Sharing database, including all patients with T2 HCC receiving priority listing from 2010 to 2014, a dropout risk score was created from a developmental cohort of 2,092 patients in LWRs, and tested in a validation cohort of 1,735 patients in SWRs and 2,894 patients in MWRs.

RESULTS

On multivariable analysis, 1 tumour (3.1-5 cm) or 2-3 tumours, alpha-fetoprotein (AFP) >20 ng/ml, and increasing Child-Pugh and model for end-stage liver disease-sodium scores significantly predicted wait-list dropout. A dropout risk score using these 4 variables (C-statistic 0.74) was able to stratify 1-year cumulative incidence of dropout from 7.1% with a score ≤7 to 39.5% with a score >23. Patients with a dropout risk score >30 had 5-year post-LT survival of 60.1% vs. 71.8% for those with a score ≤30 (p = 0.004). There were no significant differences in post-LT survival below this threshold.

CONCLUSIONS

This study provided evidence that patients with HCC with the highest dropout risk have aggressive tumour biology that would also result in poor post-LT outcomes when transplanted quickly. Below this threshold risk score of ≤30, priority status for organ allocation could be stratified based on the predicted risks of wait-list dropout without significant differences in post-LT survival.

LAY SUMMARY

Prioritising patients with hepatocellular carcinoma for liver transplant based on risk of wait-list dropout has been considered but may lead to inferior post-transplant survival. In this study of nearly 7,000 patients, we created a threshold dropout risk score based on tumour and liver-related factors beyond which patients with hepatocellular carcinoma will likely have poor post-liver transplant outcomes (60% at 5 years). For patients below this risk score threshold, priority status could be stratified based on the predicted risk of wait-list dropout without compromising post-transplant survival.

BACKGROUND

An estimated 10% of male adults have split or dribbled stream leading to poor hygiene, embarrassment, and inconvenience. There is no current metric that measures male stream deviation.

OBJECTIVE

To develop a novel method to measure spray in normal and abnormal anatomical conformations.

DESIGN, SETTING, AND PARTICIPANTS

We developed a novel platform to reliably describe spray. We used cadaveric tissues and 3D Printed models to study the impact of meatal shape on the urinary stream. Cadaveric penile tissue and 3D printed models were affixed to a fluid pump and used to simulate micturition. Dye captured on fabric allowed for spray detection.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Spray pattern area, deviation from normal location, and flowrates were recorded. Computational fluid dynamic models were created to study fluid vorticity.

RESULTS AND LIMITATIONS

Obstructions at the penile tip worsened spray dynamics and reduced flow. Ventral meatotomy improved flowrate (p0.05) and reduced spray (p0.05) compared to tips obstructed ventrally, dorsally or in the fossa navicularis. 3D models do not fully reproduce parameters of their parent cadaver material. The average flowrate from 3D model was 10ml/sec less than that of the penis from which it was derived (p = 0.03). Nonetheless, as in cadavers, increasing obstruction in 3D models leads to the same pattern of reduced flowrate and worse spray. Dynamic modeling revealed increasing distal obstruction was correlated to higher relative vorticity observed at the urethral tip.

CONCLUSIONS

We developed a robust method to measure urine spray in a research setting. Dynamic 3D printed models hold promise as a methodology to study common pathologies in the urethra and corrective surgeries on the urine stream that would not be feasible in patients. These novel methods require further validation, but offer promise as a research and clinical tool.

BACKGROUND

Exercise and a healthy diet can improve the quality of life and prognosis of prostate cancer survivors, but there have been limited studies on the feasibility of web-based lifestyle interventions in this population.

OBJECTIVE

This study aims to develop a data-driven grounded theory of web-based engagement by prostate cancer survivors based on their experience in the Community of Wellness, a 12-week randomized clinical trial designed to support healthy diet and exercise habits.

METHODS

TrueNTH's Community of Wellness was a four-arm pilot study of men with prostate cancer (N=202) who received progressive levels of behavioral support (level 1: website; level 2: website with individualized diet and exercise recommendations; level 3: website with individualized diet and exercise recommendations, Fitbit, and text messages; and level 4: website with individualized diet and exercise recommendations, Fitbit and text messages, and separate phone calls with an exercise trainer and a registered dietitian). The primary aim of the study is to determine the feasibility and estimate the effects on behaviors (results reported in a separate paper). Following the 12-week intervention, we invited participants to participate in 4 focus groups, one for each intervention level. In this report, we used grounded theory analyses including open, axial, and selective coding to generate codes and themes from the focus group transcripts. Categories were refined across levels using embodied categorization and constant comparative methods.

RESULTS

In total, 20 men with prostate cancer participated in the focus groups: 5, 4, 5, and 6 men in levels 1, 2, 3, and 4, respectively. Participants converged on 5 common factors influencing engagement with the intervention: environment (home environment, competing priorities, and other lifestyle programs), motivation (accountability and discordance experienced within the health care system), preparedness (technology literacy, health literacy, trust, and readiness to change), program design (communication, materials, and customization), and program support (education, ally, and community). Each of these factors influenced the survivors' long-term impressions and habits. We proposed a grounded theory associating these constructs to describe the components contributing to the intuitiveness of a web-based lifestyle intervention.

CONCLUSIONS

These analyses suggest that web-based lifestyle interventions are more intuitive when we optimize participants' technology and health literacy; tailor interface design, content, and feedback; and leverage key motivators (ie, health care providers, family members, web-based coach) and environmental factors (ie, familiarity with other lifestyle programs). Together, these grounded theory-based efforts may improve engagement with web-based interventions designed to support prostate cancer survivorship.

AIMS

Penile clamps offer an alternative to manage male urinary incontinence in patients who are unfit for surgery. Patient experience with penile clamps is poorly understood. Our study elucidates patient opinions on commercially available penile clamps and the factors that associate with favorable and unfavorable opinions.

METHODS

We collected Amazon reviews of all penile clamps marketed for male urinary incontinence from November 2011 to January 2020 and qualitatively assessed the overall sentiment towards penile clamps, key praises and key complaints. Covariates such as designated Amazon star rating were further explored for association with coding patterns.

RESULTS

Amazon reviews of penile clamps were found to be more positive (n = 425) in overall sentiment than negative (n = 294). The most frequent praise was effective incontinence control (n = 334) and the most frequent complaint was bad design or material (n = 166). The majority of reviews were for lower priced penile clamps, had higher Amazon star ratings, were written for Wiesner-produced clamps, and were written more recently (i.e., 2015-2020). Penile clamps with higher Amazon star ratings were more often coded positive and with a praise compared to lower rated penile clamps.

CONCLUSIONS

Penile clamps are seen favorably by users as an effective treatment modality for male urinary incontinence. User reviews suggest opportunities for improvement in penile clamp design. The most frequently reviewed clamp seen positively is the Wiesner Incontinence Clamp Penile Clamp whereas the most frequently reviewed clamp seen negatively is the Pacey Cuff Male Incontinence Device.

OBJECTIVE

To explore the relationship between research time during urologic training and career academic success.

METHODS

We included urologists graduating residency between 2002 and 2008 from 36 programs affiliated with a top 50 hospital for urology as ranked by the United States News and World Report, and collected research time during residency, fellowship training, current appointment (private practice, assistant professor, associate professor, professor, chair), national institutes of health (NIH) grant accrual, NIH R01 grant accrual, and current H-index in Scopus database. Publication output during and after residency was identified through the PubMed database.

RESULTS

In our cohort of 543 urologists, 66.3% of graduating trainees pursued private practice. Increasing residency research time was associated with increased publication count (P .001), pursuit of professor positions (P .001), and NIH funding (P .001). One year of dedicated research increased the odds of being in the top 10th percentile of publication output during residency (odds ratio [OR]: 5.7, 95% confidence interval [CI]: 2.7-12.1), pursuing a fellowship (OR: 2.0, 95% CI: 1.3-3.1), promotion to professor (OR: 4.9, 95% CI: 2.0-12.2), obtaining a NIH grant (OR: 6.2, 95% CI: 2.3-16.5), and decreased the odds of pursuing private practice (OR: 0.4, 95% CI: 0.3-0.6). As amount of time dedicated to research in urologic residency increased from 3-4 to 6-12 months, OR increased for career academic success metrics.

CONCLUSION

Although a minority of trainees enter academics, dedicated time for research in urologic residency is associated with career academic success, with more research time associated with increased publication output, academic appointments, and grant funding.

Seriously ill surgical patients require complex and integrated surgical, interventional, and medical management to balance the risks and benefits that complicate decision-making. Palliative care principles can aid surgeons in these cases. To illustrate this, we describe a scenario of a patient with unresectable hepatocellular carcinoma with portal vein tumor thrombus causing portal hypertension. We discuss options for managing the sequelae of portal hypertension, including varices and ascites. We explore the interventional and surgical options for mitigating or palliating the underlying portal hypertension. Advances in interventional radiological techniques can facilitate the creation of transjugular intrahepatic portosystemic shunts (TIPSs), even with extensive portal vein thrombus. If interventional approaches are not possible, surgical shunts can be considered but carry significant risks that must be weighed against the benefits. To communicate effectively, we outline key steps to breaking bad news. To make shared decisions in challenging cases, we describe how to elicit a patient's hopes, expectations, concerns, and preferences; how to synthesize goals of care from these stated values; and how to use those goals to guide decision-making.