Haptic Guidance Based on All-Optical Ultrasound Distance Sensing for Safer Minimally Invasive Fetal Surgery

Abstract

By intervening during the early stage of gestation, fetal surgeons aim to correct or minimize the effects of congenital disorders. As compared to postnatal treatment of these disorders, such early interventions can often actually save the life of the fetus and also improve the quality of life of the newborn. However, fetal surgery is considered one of the most challenging disciplines within Minimally Invasive Surgery (MIS), owing to factors such as the fragility of the anatomic features, poor visibility, limited manoeuvrability, and extreme requirements in terms of instrument handling with precise positioning. This work is centered on a fetal laser surgery procedure treating placental disorders. It proposes the use of haptic guidance to enhance the overall safety of this procedure and to simplify instrument handling. A method is described that provides effective guidance by installing a forbidden region virtual fixture over the placenta, thereby safeguarding adequate clearance between the instrument tip and the placenta. With a novel application of all-optical ultrasound distance sensing in which transmission and reception are performed with fibre optics, this method can be used with a sole reliance on intraoperatively acquired data. The added value of the guidance approach, in terms of safety and performance, is demonstrated in a series of experiments with a robotic platform.

Developing a novel force forecasting technique for early prediction of critical events in robotics

“…Forces exerted from the surrounding tissue can increase rapidly causing the needle to laterally bend and buckle when encountering stiff tissue [16,17]. On further insertion, either the needle tip could break, or membrane puncture can occur causing undesired tissue rupture and bleeding [18]. Therefore, buckling can cause damage to both the needle and the tissue [19,20].…”

“…CFDL-MFP forecasts were performed independently for 4 different initial values ofF N ðk o Þ to study their effects on stability. For eachF N ðk o Þ, the stability indicator,S was computed according to Eq (18). For allF N ðk o Þ < 1,S ¼ 1 indicating model stability.…”

Robotic Control of a Multi-Modal Rigid Endoscope Combining Optical Imaging with All-Optical Ultrasound

“…Due to their small form factor, fetoscopes often suffer from a limited field of view, which complicates the manipulation of these endoscopes [1]. While fetoscopy is traditionally performed manually, incorporating robotics has the potential to improve the stability of imaging devices through precise control of the instrumentation [3], [4]. In addition, the ability to execute pre-computed trajectories and utilise feedback from other sensors, such as strain gauges for force control, can improve image acquisition strategies and enable high quality multi-modal imaging [5], [6], that can be automatically optimized for specific procedure segments [7].…”

“…OpUS can provide high resolution imaging from small form factor devices and has recently been demonstrated for real-time in vivo guidance from a surgical needle [12]. Additionally, combination with robotics shows potential for improving control during surgical procedures [4].…”

Large area all-optical ultrasound imaging using robotic control

“…6 Additionally, the combination of all-optical robotics has demonstrated the potential for its use to provide feedback and improve robotic control. 7 In this study we combined a robotic manipulator with a fibre optic ultrasound probe, which comprised a nanocomposite coated multimode fibre for ultrasound generation and a concave Fabry-Pérot fibre optic hydrophone for ultrasound reception. The ultrasound probe was built into a custom rigid endoscope and a custom computer interface was used to acquire and display ultrasound A-lines in real-time during robot manipulation.…”