This system uses computerized tracking devices to monitor the position of instruments relative to the patient’s anatomical landmarks. The location of these instruments is depicted on a 3-dimensional video display of the preoperative computed tomographic (CT) or magnetic resonance imaging (MRI) scan.
Computer-aided Navigation surgery technology has permitted a direct comparison of the intra operative anatomy with preoperative imaging information. The surgeon may point to a specific structure with the Navigation instrument and then view the location of the instrument tip on the CT image. The use of Navigation systems may allow for more precise dissections and greater rates of sinus patency outcomes and fewer complications.
The navigation system is used to reduce complication rates, completely remove the disease, and hasten the recovery after surgery. Image-guided surgery compensates the limitations of surgical endoscopy and used as an important tool for Sinus surgery and has demonstrated great promise in recent literature. Advances in portable MRI and volumetric CT technology have enhanced the efficiency and safety of intra operative imaging.
Despite the availability of excellent nasal telescopes and high-resolution preoperative computed tomography (CT), major complications such as blindness, central nervous system (CNS) trauma, and even death still occur, because the traditional ESS may be compromised by anatomic complexity or intra operative bleeding.
Sinus surgery has markedly improved with the introduction of surgical navigation systems, preoperative imaging techniques and intra operative visualization tools.
Image-guided surgery begins with obtaining a CT scan. The imaging data set is transferred via optical disk, CD-ROM, or computer network to the operating room, where it is loaded into the workstation. The images are brought up on the IGS i.e. Image guided surgery system prior to the procedure and checked for image quality and accuracy.
Under General Anesthesia a tight headband or stickpad is applied for the localization and registration. In the optical system light reflectors or glions are placed on the headset and also on the active probe, and both the instruments are brought in vicinity line of the infrared cameras mounted on the workstation.
Once verification of the entered data, head probe and active instruments is done, the process of registration is completed by means of cross checking of facial markers, surface or laser registration of probes. Once registration is complete and the instruments are calibrated by the system, accuracy is verified by testing various known landmarks on the patients face and in the nares. The coordinates are stored and used throughout the procedure to monitor any changes in the accuracy of the device. Done correctly the system becomes ready for navigation.
- Navigation in Endoscopic Sinus Surgery: The First Indian Experience, Devinder Rai, Manish Munjal,and Varun Rai, Otolaryngol Clin North Am. Indian J Otolaryngol Head Neck Surg. 2009 Oct;42(5):765-79, viii. doi: 10.1016/j.otc.2009.08.014.
- Intraoperative imaging for otorhinolaryngology-head and neck surgery, Isaacs S1, Fakhri S, Luong A, Citardi MJ, Ann Saudi Med. 2010 Mar-Apr; 30(2): 149–152., doi: 4103/0256-4947.60522.
- Computer-aided endoscopic sinus surgery: a retrospective comparative study, Jamil N. Al-Swiahband Surayie H. Al Dousary.