Robotic surgery and Transoral robotic surgery (TORS) in ENT

Robotic surgery is telesurgery, i.e. the surgeon performs surgery by being away from patient through a console which manipulates the robotic instruments according to surgeon maneuvers on the console. Transoral robotic surgery (TORS) was initially conceived for oropharyngeal cancer.

Write short notes on: What is robotic surgery? a) Transoral Robotic Surgery TORS.  DNB ENT Theory Question June 2014, Dec 2016, Dec 2019

Parts

Master surgeon console:

On which the surgeon sits, uses his hands to manoeuvre instruments via master controllers and sees 3 -dimensions vision through the stereoviewer

Patient cart:

Patient lies on this cart and the instruments are docked (fixed) into the ports on the robot wheel cart over this table. There are 4 arms for instruments with one of them being camera port. Ports are placed as in laparoscopy and then the instruments
inserted in ports through robot arms to connect them to the master console control.

Vision cart:

Has a binocular vision through 3-D endoscope connected to camera.

Advantages

Stereoscopic depth perception (3-D vision)
More range of motion due to wrist like motion present in robotic instruments which give some degrees of freedom in movement
Improved hand eye co-ordination as the robotic camera is controlled by the surgeon and is held in steady position by robotic cart so no fatigue or tremors
Less surgeon fatigue due to excellent ergonomics (sitting surgery)
Comparably less prolonged learning curves than with laparoscopy.

Limitations

Cost, Tactile Feedback
Learning curve
Duration of surgery is prolonged compared to open surgery

Commonly performed robotic procedures

Transoral surgery using the da Vinci robotic surgical system was recently reported to be suitable for performing SGL
3 arms , suction device , surgical arms and endoscope for viewing.

TORS^​1​

Theater Setup for TORS

The Da Vinci Surgical System consists of three components: a surgeon’s console, a patient-side robotic cart equipped with four arms, and a high-definition three-dimensional vision cart. Articulating surgical instruments are mounted on the robotic arms, which are introduced into the upper aerodigestive tract through the mouth of the patient and manipulated remotely with master robot manipulators from the surgeon’s console. An assistant at the head of the patient helps with smoke evacuation, suction, application of ligatures and retraction. This allows four independently controlled instruments to be used simultaneously in the intra-oral environment, providing unparalleled manoeuvrability.

The general set-up of transoral robotic surgery includes the robot, generally placed at a 45 degree angle to the left of the head of the patient’s bed. The patient, depending upon the surgical approach is intubated with a nasotracheal tube. The anesthesia team is often set-up 90 degrees to the right of the patient, or, in some cases, 180 degrees at the foot of the patient. The scrub nurse is placed to the right or left of the head of the bed while the assistant surgeon sits at the head of the bed.

The primary surgeon then sits at the console. The da Vinci system is set-up where a slave monitor is placed for the use by the assistant surgeon and scrub tech. A speaker system allows for clear communication from the primary
surgeon to the team. The assistant surgeon works to keep the camera clean, smoke out of the surgical field,
and assist with cautery as needed.

There are multiple mouth gags available for use including the Macgyver and Crow-Davis. The Feyh-Kastenbauer or FK retractor has become very popular. It has multiple points of rotation for different ways to suspend the patient. This allows for different aspects of exposure. These multiple points of rotation are especially helpful in base of tongue masses. The camera source is brought in to the midline of the mouth.

The two working arms are set at roughly 30-45 degree angles to the right and left of the camera allowing for maximal freedom of movement without hitting the camera or the other working arm. Once must take special care at the molar teeth. A distinct disadvantage of the robot is a lack of tactile feedback.

Radical tonsillectomy is generally performed using a bovie cautery and a Maryland retractor.
Mucosal incisions are made along the tonsillar fossa in the same manner as a standard tonsillectomy. Once
deep to the superficial layers, the palatopharyngeus, palatoglossus and superior constrictor muscles are
identified. The muscles are then transected and the tumor is retracted medially. The parapharyngeal fat is
often exposed at this point. Deep to the parapharyngeal fat is the carotid artery.

During the dissection, two large arteries are often identified. Those are the ascending palatine and ascending pharyngeal artery. These arteries should be ligated with vascular clamps. Dissection is then brought inferiorly toward the
base of tongue where the styloglossus muscle is often identified. The glossopharyngeal nerve can be identified at this time. The inferior cuts are then made and the tumor is retracted further medially and taken off the posterior pharyngeal mucosa.

Uses of Robotic Surgery in ENT

HPV-Related Squamous Cell Cancers, Non–HPV-Related Squamous Cell Cancers, Non-Squamous Cancers, Oropharynx and
Supraglottic Cancers, Unknown Primary, Recurrent Cancer and Benign tumours of the parapharyngeal and retropharyngeal
spaces.

Advantages of TORS:

o The three-armed robotic system is said to confer improved-
o three-dimensional optics.
o tissue manipulating/cutting maneuverability.
o The “endowrist” design allows for flexibility in movement at the end of the robotic instruments

Disadvantages of TORS

o Some optical resolution is lost over a high-quality operating microscope
o the arms are straight are rigid, and cannot be maneuvered down a laryngoscope
o necessitating spatulate retraction of the tongue.
o significant instrument crowding

Currently; the robot appears to offer no real advantage over endoscopic laser resection although its application in supraglottic tumors may increase with future refinements.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3782590/pdf/can-7-359.pdf