Smartphone-based Laparoscopy: A Novel Cost-effective Laparoscopic Imaging Technique

Vivian E de Ruijter, MD¹, Brain Huynh², Kay Hung³, Brian Bradley⁴, Alison Keiper, BS², Iretiayo Akinola, BS⁵, Lee L Swanstrom⁶, James K Wall¹, James N Lau¹. ¹Stanford University, Department of Surgery, ²Stanford University, Department of Mechanical Engineering, ³Stanford University, Department of Biomedical Engineering, ⁴Stanford Universty, Department of Biomechanical Engineering, ⁵Stanford University, Department of Electrical Engineering, ⁶IHU-IRCAD, University Hospital of Strasbourg, Strasbourg, France

OBJECTIVE OF THE TECHNOLOGY OR DEVICE

Smart phones are increasingly being used among health professionals in their daily clinical activities. Recent advances and the widespread availability of smartphones have ushered in a new wave of innovations in healthcare. Rapid advances in capturing and sharing images have resulted in the use of smartphones as clinical-imaging devices in various fields. These devices represent a relatively cost-effective solution for capturing high-quality images (e.g. video) during clinical procedures. We describe a novel method of performing inexpensive, portable laparoscopy by attaching a commercially available smartphone to a laparoscope through a custom-machined coupling device.

DESCRIPTION OF THE TECHNOLOGY AND METHODS OF ITS USE OR APPLICATION

The study was performed in 2 phases. In the first, laparoscopic experts viewed three laparoscopic videos recorded using a cadaver model. These videos contained footage recorded with 3 imaging systems: 1) a high definition (HD) camera, 30° 10mm laparoscope and xenon light source (all Stryker®, San Jose, CA); 2) an iPhone 5S (iPhone 5S, Apple Inc., Cupertino, CA), a custom-made coupling device, a 30° 10mm laparoscope, and a xenon light source; 3) an iPhone 5S, a custom-made coupling device, a 30° 10mm laparoscope, and a widely available commercial LED light source (Energizer®, Saint Louis, MO). The experts were blinded and asked to rate the resolution, brightness, color and overall quality of each video using the Likert-Scale (1-Very Poor, 5-Excellent). In the second phase, each of the imaging systems was evaluated for color resolution (see figure 1) with the ColorChecker chart (X-Rite, Grand Rapids, MI), and for imaging system 1 and 2 the image resolution was assessed using the 1951 USAF Chart Target (Edmund Industrial Optics,TM Barrington, NJ).

PRELIMINARY RESULTS

Eight laparoscopic experts participated in the first portion of the study. Imaging system number 1 rated for the resolution 3.9 (SD 0.64), brightness 2.6 (SD 0.92), color 3.9 (SD 0.64) and the overall quality 3.8 (SD 0.46). Imaging system number 2 rated 4.3 (SD 0.46) for the resolution, 3.6 (SD 0.92) for the brightness, 3.9 (SD 0.64) Color, and 3.9 (SD 0.64) for the overall quality. Imaging system number 3 rated 3.4 (SD 1.06) for the resolution, 3 (SD 0.53) for the brightness, 3.6 (SD 0.92) for the color, and 3.1 (SD 0.64) for the overall quality. The color resolution of the standard laparoscopic imaging system was ?18.6, versus the iPhone imaging set up with a ?22.20 for the xenon light source, and ?19.44 for the commercial LED light source.

CONCLUSIONS AND FUTURE DIRECTIONS

This study shows that smartphones have equivalent performance to traditional laparoscopic imaging systems. In addition, smartphones have great potential as low cost, portable clinical-imaging devices in the field of surgery. This innovative use of smartphone technology during minimally invasive surgery has vast implications for research, education and, ultimately, optimizing patient-care.