Impact of Camera Deviation on Penile Curvature Assessment Using 2D Pictures

Area of Science:

• Urology
• Medical Imaging
• Biomechanical Engineering

Background:

• Accurate curvature assessment (CA) is crucial for managing Peyronie's disease.
• While in-office induced erection CA is standard, penile photography is often used for convenience.
• Potential inaccuracies in CA can arise from camera angle deviations during 2D image acquisition.

Purpose of the Study:

• To investigate the impact of camera angle deviations on the accuracy of penile curvature assessment.
• To quantify the picture assessment error (PAE) resulting from various camera deviations.

Main Methods:

• Utilized 5 models with known uniplanar curvatures (40°-120°).
• Rotated the camera around a fixed model in 10° increments up to 90° in vertical and horizontal planes.
• Analyzed 2D images using a goniometer and calculated PAE based on trigonometry.

Main Results:

• High intraobserver and interobserver reliability (ICC > 0.99) were observed.
• Horizontal axis deviation caused underestimation for <90° curvatures and overestimation for 120°.
• Vertical axis deviation had an inverse effect; PAE increased exponentially with deviation, exceeding 100% at 80°.
• PAE remained below 5% for deviations within 0°-20°.

Conclusions:

• Camera angle is a significant factor influencing penile curvature assessment accuracy.
• Maintaining a camera deviation within 20° is recommended for reliable measurements.
• Clinicians should aim for perpendicular imaging or consider additional photos to minimize PAE.