In this paper, the authors present an innovative vision platform for laparoendoscopic single-site (LESS) surgery based on a wired and magnetically activated 5-degrees-of-freedom robot with stereovision. The stereoscopic vision module, developed using two off-the-shelf cameras and a light emitting diodes lighting system, is mounted on the robot tip. An autostereoscopic screen is adopted to display the surgical scenario as an alternative to 3-D helmets or polarizing glasses. A rough position of the stereocamera can be determined along the abdominal wall by dragging the robot with a set of external permanent magnets (EPMs). Once the camera is set in the desired position, the EPMs provide fixation, while the internal mechanism allows fine tilt adjustment. Considering the deformable round shape of the insufflated abdomen wall and in order to replicate the precise roll motion usually provided by the endoscopist's hands, this prototype embeds an actuated mechanism that adjusts the stereocamera horizon and thus prevents any visual discomfort. Finally, the platform was preliminarily tested in vivo in a LESS scenario, demonstrating its advantages for eliminating potential conflicts with the operative tools and enabling the introduction of an additional instrument through the same access port used for stereoscopic vision.

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In the near future, it is likely that 3-dimensional (3D) surgical endoscopes will replace current 2D imaging systems given the rapid spreading of stereoscopy in the consumer market. In this evaluation study, an emerging technology, the autostereoscopic monitor, is compared with the visualization systems mainly used in laparoscopic surgery: a binocular visor, technically equivalent from the viewer's point of view to the da Vinci 3D console, and a standard 2D monitor. A total of 16 physicians with no experience in 3D interfaces performed 5 different tasks, and the execution time and accuracy of the tasks were evaluated. Moreover, subjective preferences were recorded to qualitatively evaluate the different technologies at the end of each trial. This study demonstrated that the autostereoscopic display is equally effective as the binocular visor for both low- and high-complexity tasks and that it guarantees better performance in terms of execution time than the standard 2D monitor. Moreover, an unconventional task, included to provide the same conditions to the surgeons regardless of their experience, was performed 22% faster when using the autostereoscopic monitor than the binocular visor. However, the final questionnaires demonstrated that 60% of participants preferred the user-friendliness of the binocular visor. These results are greatly heartening because autostereoscopic technology is still in its early stages and offers potential improvement. As a consequence, the authors expect that the increasing interest in autostereoscopy could improve its friendliness in the future and allow the technology to be widely accepted in surgery.

A miniaturized color camera module for disposable endoscopic applications and minimally invasive surgery has been designed and developed. The module consists of a Complementary Metal Oxide semiconductor (CMOS) sensor, miniaturized optics, a Light Emitting Diode (LED)-based illuminator and a connector on a single substrate. The compact size (5.0 mm × 8.2 mm × 7.0 mm), high-efficiency illumination, VGA resolution and good image quality allow it to be used in endoluminal procedures. A demonstration system has been built and tested in vivo. The module is connected through a 1.5-m long cable to a receiver board, which transfers the data stream to a Personal Computer (PC). A dedicated software controls the hardware setting and displays the image, after having performed various color and image processing tasks.

A custom CMOS image sensor designed for low power endoluminal applications is presented. The fabricated chip includes a 320 × 240 pixel array, a complete read-out channel, a 10-bit ADC converter, a series of DACs for internal references and digital blocks for chip control. The complete functionality of the chip is guaranteed through 7 signal pins, used for the I 2 C-like input and LVDS output interfaces. Prototypes were produced using UMC 0.18 m-CIS (CMOS Image Sensor) technology for both monochrome and colour-RGB versions. Due to its high sensitivity, a pinned photodiode was implemented. The imager was electrically and optically characterized and preliminary ex-vivo tests were performed. Characterization results show state-of-the-art performance in terms of power consumption (<40 mW for the core), which is less than half compared to off-the-shelf sensors, and light sensitivity (0.1 lux@555 nm for the monochrome imager), which makes sensor performance comparable to CCD technology performance for single chip endoluminal applications.