Navigation system was introduced into endoscopic sinus surgery, and the accuracy and safety of operation improved by leaps and bounds. The endoscopic sinus surgery using navigation system in our hospital is accepted as advanced medicine, and an indication disease serves as a intractableness sinusitis, a paranasal cyst, a circumference organ disease, and a paranasal tumor. While reporting our experience with navigation system, we examined the advantage of navigation surgery, the important matter, the indication.
Navigation system strongly supports endoscopic sinus surgery (ESS) in the case of postoperative maxillary cysts which has multiple cysts, bony cyst wall, and anatomical malformation. We presented a navigation guided ESS for multiple postoperative maxillary cysts. The case was 52-year-old woman, who performed Caldwell-Luc sinus surgery over 30 years ago. Four cysts were existed in the right, and two in the left maxillary sinus. In the operation, navigation system helped to make a rout simple for reaching cyst wall even the cyst had distance from both inferior and middle nasal meatus. And another point of usefulness of navigation system was that we could find and punctured a cyst which was unclear by preoperative CT image.
There are two methods for the dacryocystorhinostomy one is an intranasaldacryocystorhinostomy and the other is a dacryocystorhinostomy from outside of the face. For the cosmetic reason, the intranasal operation is have an advantage. However, it is sometimes difficult to find outlacrimal sac from the nose. We used the image-guided navigation system for dacryocystorhinostomy. This system was very useful when we find lacrimal sac from nose.
Endoscopic orbital decompression has been used as a treatment of severe exophthalmos and/or optic nerve compression with visual loss in patient with thyroid eye disease. We reported one case of thyroid eye disease to be treated with endoscopic orbital decompression using navigation system. This method is very effective for preventing surgical complication during surgery.
The translabyrinthine approach for vestibular schwannomas provides full access to the internal auditory canal, enabling total tumor removal. In the safe manipulation of tumor inside the internal auditory canal, removal of the bone between the internal auditory canal and jugular bulb is important. The anatomical variation of the jugular bulb is sometimes makes this challenging. We applied an image-guidance system in the detection of the jugular bulb in three patients. In two patients, the image-guidance system showed the jugular bulb correctly, and the other one, the system failed to point out correct location.
The registration process determines the overall accuracy of image-guided surgery. Otologic surgery requires submillimetric accuracy, and it is known that invasive registration using bone-anchored fiducial markers acquire less error. We have developed a less-invasive strategy for attaching bone markers by transferring the markers to the patient's bone intraoperatively. The template of the bone surface (the “stamp”) was produced from the edited CT with virtual fiducial markers attached on the temporal bone. By matching the contour of the stamp with patient's bone surface after the bone was exposed, we could accurately and non-invasively transfer virtual markers on patient's bone for the registration. Our method would be a useful IGS method in the field of otology where both accuracy and non-invasiveness are required.
The StealthStation navigation system, which employed optical tracking technology, was introduced in 1995 and had been remodeled every few years. We have achieved the top market share of the navigation system in worldwide and Japan. Currently, we deliver 2 types of navigation hardware for otolaryngology surgeries, “Treon” and “Tria”. The range of applications are “ENT application” for nose surgery, the “FrameLock” system for ear surgery. We are preparing for the release of an electromagnetic navigation in Japan. Since this system se the small reference frame, it is the best for the nose surgery which does not usually apply a head fixation to a patient. We introduce the method and technique to achieve high navigation accuracy in ear surgery.
“Kolibri ENT” has been developed using the cutting edge technology of BrainLAB (Germany), which is highly evaluated for its surgical navigation technology both domestically and internationally, with the concept of solving outstanding issues in conventional navigation systems-long setting time, complicated operation, bulky main unit, and so on. This is the navigation system that ENT practitioners can use in their daily surgeries, realizing its “SPEEDY, SIMPLE, and SMART” usage.
There are many reports which mentioned about the benefit of image-guided navigation system for the surgery of head and neck region. The wider the system become used, the more problems were raised ex; The indication of the system, or how accurate should it be. In this study, we report our experiments of the system, the estimates of the surgeon who used this system, the indication of the system, and the risk of the system. We found that the navigation system was very useful for the ENT surgery especially if the case was anatomically difficult.
The Ministry of Health, Labour and Welfare, and the Ministry of Economy, Trade and Industry are working together to establish guidelines for medical equipment to be used in navigated surgery. A committee has also been formed to investigate the development and uses of medical navigation equipment. Evidence attesting to the usefulness of navigation systems in surgery in the field of Otorhinolaryngology has been steadily accumulating, however, due to the still high costs of the equipment and the lack of certification for payment under health insurance schemes, implementation by individual departments remains difficult. The fact that within this meeting there have been many reports of the use of navigation, but there are still no clear guidelines as to indications, points up the difficulty of application procedures for leading medical technology. In the fall of 2003, the Departments of Neurosurgery, Orthopedics and Otorhinolaryngology at our institution jointly purchased a StealthStation TREONTM manufactured by Medtronic Sofamor Danek, Co., Ltd., and began training and education in its use. The system is now being used in nearly all cases of endoscopic sinus surgery as well as being incorporated in some cases of ear, and head and neck surgery and the usefulness, accuracy, and preparation time in the clinical setting has been investigated. Here, with an eye towards future application of this leading technology in the field of Otorhinolaryngology, we report our retrospective review of cases seen in our department as well as our investigation into the guidelines for use of navigation systems.
We have used navigation system during surgery for head and neck region in 62 cases including 35 anterior skull base surgeries and 18 lateral skull base surgeries since September 2000 to August 2007. Navigation system was very useful in almost all anterior skull base surgeries and some of lateral skull base surgeries, especially when the lesion was adjacent to important organs (eye ball, optic nerve and internal carotid artery etc.) and liable to bleed. It was also very useful in case of volume reduction surgery for fibrous dysplasia of facial skull. The necessity of navigation system didn't match the difficulty of surgery evaluated by Gaihoren in the report titled “Gaihoren's tentative plan concerning the remuneration for surgery (6th edition)” in otolaryngology, head and neck region.
We present our experience of image-guided endoscopic sinus surgery (IG-ESS). We have experienced 444 cases of IG-ESS for 10 years at Jikei University Hospital. About 10% of all ESS cases were need for image-guide system. This system has been proven to facilitate complicated ESS and decrease the need for revision procedure. However, this system did not apply to the intraoperative anatomic changes that occur throughout the procedures. Nowadays, intraoperative CT scanning can be performed undergoing ESS in our hospital. We think that intraoperative update has the potential to improve the extent of surgery in patients with complicated anatomy and extensive diseases, such as skull-base diseases or orbital diseases.
Navigation system for otolaryngological surgery has been a very useful and low invasive device. Endoscopic sinus surgery by using a navigation system was performed at forty-nine patients at our hospital for this four years. Our principle of adaptation for navigation surgery was reported at the present time.
Computer assisted endoscopic sinus surgery was approved as advanced medical care as “the endoscopic nose and paranasal operations using navigation system” for from Ministry of Health, Labour and Welfare in August, last year. The patient bears expense for advanced medical care by oneself. A subject of the advanced medical care is prescribed with “a chronic sinusitis, a paranasal cyst or a paranasal benign tumor”. However, the pathology of a patient is various even if we lump sinusitis and a paranasal cyst together. It is necessary to evaluate pathology of a patient thoroughly from preoperative endoscopic inspection and preoperative CT finding. Then a surgeon determines whether “navigation surgery as advanced medical care” is indicated or not. If navigation takes it as need or utility, we explain it to the patient enough and obtain consent. Aiming at improvement of postoperative outcomes, it is important that we perform navigation surgery more precisely.
To construct minimal invasive navigation in real time, we introduce optical measurement techniques with tumor sensitizer, which are 2-Color Photo-Dynamic Diagnosis (2C-PDD), Near Infrared Fluorescence Computed Tomography (NIR-FCT) and 2-Color Optical Coherence Dosigraphy (2C-OCD). Applying 2C-PDD to navigation system of brain tumor, one can obtain high contrast images between tumor lesion and normal tissue. To detect a tumor site deeply located, we employ NIR-FCT and construct fluorescence computed tomography images by convolution back projection method. To detect infinitesimal tumor, we develop a functional optical coherence tomography, namely 2C-OCD, which enables to visualize both the scatterer density and drug concentration.
[Objective] To develop a distance education system that would allow novices to acquire manual skills in Endoscopic Paranasal Sinus Surgery (ESS). [Method] Subjects: Eleven medical students (5th year) at Kanazawa Medical University (KMU). Equipment: Each KMU (Uchinada, Ishikawa) and AIST (Tsukuba, Ibaraki) site had a distance education system newly developed by AIST capable of communicating over a commercial Internet connection. Each system had two virtual mirrors in which video images of a trainee and a trainer are synthesized as if they are standing side-by-side and performing the same procedure on the same patient model. With the system, the trainee can easily note differences in equipment positions and mimic the motions of the trainer very quickly. Procedure: A trainee at AIST remotely taught subjects at KMU two surgical tasks (A: Probing of the nasofrontal duct, B: Aspiration of the maxillary sinus) three times, for 10 minutes each. Data recorded were subjective evaluations of remote training and task performance by the trainer and the trainee, mental workload with NASA-TLX, and force applied to the patient model by the trainee during tasks using a force-torque sensor attached to the model. [Results] (1) After performing three remote training trials, the trainer's subjective evaluation of the trainee's task performance improved significantly (Wilcoxon Signed Ranks Test, p<0.05). (2) Task completion time did not differ significantly. (3) Size of the force vector (average and max. values during each trial) increased after remote training compared to that of the trainers (t-test, p<0.05). [Discussion] Surgical skills were acquired using a distance learning system. It was confirmed by the retention checking experiment conducted two months later. Time is not a good measure for the manual skills level of novices. Increase of the force applied to the patient model was actually observed in our previous experiment of gauze packing by subjects with different surgical experiences (less experienced surgeons applied greater force than either experts or novices). [Conclusions] Distance surgical skill training is possible using our training system that presents synthesized virtual mirror images of the trainer and the trainee.
We have newly developed a navigator for endoscopic paranasal sinus surgery. In this system, the optical 3D scanner captures the positions of patient and endoscope simultaneously. The software calculates the positions in the center observed with an endoscope, and presents them on the preoperative CT images. This system requires no specific endoscope and surgical instrument without any markers such as spheres.
A virtual reality temporal bone (VR TB) simulator has become a valuable tool to resident education in otolaryngology. The simulator must provide a realistic representation of tissue in three dimensions, with haptic feedback (the operator must feel the sensation of different drill speeds, pressures, and directions). We present our experience with the simulator for temporal bone practical training. Five residents drilled both a cadaveric TB and a simulated VR TB. We suggest that the ability of a simulator to provide objective assessment of residents as they transition from laboratory-based learning to operative otology provides a useful measurement.
Various kinds of nasal and paranasal lesions may involve the skull base, however, surgical approaches to lesions in this area are difficult because of the anatomical complexity. In order to facilitate both surgical planning and actual surgery, we had introduced several devices such as navigation system and/or endoscope. In addition to these, a three-dimensional model was made from images of actual patients. These devices had facilitated not only surgical planning but also actual surgical procedure. In this paper, we report our experiences of applications of these supporting systems for skull base surgery.
Our 3D model, OMeR (JP Pat. 3927487, US Pat. 6932610) precisely replicates the inner structure of human bones. It can be shaved using a surgical drill, burr and suction irrigator the same way as human bones. Thus, it has been proven useful for surgical planning, simulation, training, and education. Applying the manufacturing method of OMeR, we have now created a registration plate for image guided surgery, OMeR-Navi. With Axis, you can accurately and non-invasively transfer virtual markers on a patient's bone for registration. We hope our OMeR-Navi, together with OMeR, will further facilitate the complex surgery in the field of Otology and related fields.
We use the new surgical instrument, HOT biopsy forceps that cut and coagulate the target tissue. This instrument is useful of open surgery of the epiglottic cyst. We opened the glottic cysts of 7 cases using this instrument with local anesthesia. All cases presented in this paper were successful and lost any complications.
We present our experience using Nerve Integrity Monitor (NIM) for parotid grand surgery. We evaluated the meaning of using NIM and found it useful to avoid iatrogenic facial nerve injury. One of the greatest meanings of using NIM is that it can observe the damage to nerves during operation and predict the possibility of recovering from palsy after operation.
We have performed nine cases of coblation-assisted adenoidectomy in children suffering from sleep disturbed breathing. Compared with cold instruments like curettage, coblation offered better visualization of the surgical field due to minimal intraoperative bleeding throughout the procedure. To avoid damage to adjacent tissue, the volume of adenoid should be measured with wands before coblation. To avoid the incomplete tissue removal, especially close to the nasal septum, wands was needed to be flexed. How to use a coblation in tonsillectomy is also reported.