Realtime transfer of live video images in parallel with three-dimensional modelling of the surgical field in computer-assisted telesurgery.

We have carried out three-dimensional, computer-assisted, functional endoscopic sinus telesurgery. Surgeons at different locations up to 300 km apart could not only see and transfer video images but also transfer three-dimensional computer models and manipulate them in realtime during surgery. Two different approaches were used. In the first telesurgery procedure we used M-JPEG compression and transmitted the data using fibre optic connections (ATM OC-3) at a bandwidth of 155 Mbit/s. In the second telesurgery procedure video images were transmitted over four E1 digital lines, amounting to about 8 Mbit/s of bandwidth, with better compression standards, such as MPEG1 and 2. We found that MPEG2 video compression produced the best picture quality for the operating field and endoscopic cameras. For conferencing and consultation between two or more connected sites during the surgery, we used JPEG and MPEG1 video compression with audio. The main feature of our three-dimensional telesurgery was the use of three-dimensional modelling of the operative field. This is important for emergency surgical interventions. We do not advocate that inexperienced surgeons operate on patients, not even with the guidance of a remote surgeon. However, three-dimensional telesurgery may become very valuable for experienced surgeons in the future.

Our experience with FESS in children.

Between 1993 and 1996 we operated on 50 children with one of the following surgical indications: 17 children with a complication of acute rhinosinusitis and the propagation of the process towards the orbit (periorbitis), six children with an ethmoid and sphenoid foreign body (shrapnels shells), 11 children with an antrochoanal polyp, four children with nasal polyposis in cystic fibrosis and 12 children with chronic rhinosinusitis after 2-4 acute reinfections. The surgery was done under endotracheal anesthesia with hypotension. CT axial and coronal tomograms were done during the preoperative treatment. During the 2 weeks preoperative treatment, the patients with polyposis and antrochoanal polyps were treated with 4-8 mg of cortisone per os or i.m., and also with Fluticasone Propionate 100 mg twice a day and antibiotics in chronic and acute rhinosinusitis. The children's age was between 7 and 15 years. In the patients with nasal polyposis and antrochoanal polyps (n = 15) post-operatively, we had four cases of synechiae, recurrent polyposis in two and antrochoanal polyps in two cases.

Effectiveness of ultrasonography in diagnosis of maxillary sinus disease: a prospective comparison with radiographic and sinusoscopic examinations.

AIM: To assess the diagnostic accuracy of ultrasonography in comparison to radiographic and sinusoscopic techniques of maxillary sinuses examinations in acute and chronic sinus inflammations. METHODS: Ninety diseased sinuses in 50 patients (32 male and 18 female) were examined radiographically, ultrasonographically, and sinusoscopically. Ultrasonography was performed with Sinuscan 102 Sinusprint with 3.0 MHz transducer frequency, with A-mode curve display and Bulk-display. Radiography was performed in occipitonasofrontal and occipitonasomental projection, and sinusoscopy by local anesthesia using an optic instrument under 0 degrees, 30 degrees, and 70 degrees. Statistical assessment of ultrasonography sensitivity and specificity in relation to radiographic and sinusoscopic techniques was carried out. The data were compared using McNemar's test for paired data. RESULTS: Negative ultrasonographic agreed with negative radiographic findings in 18 of 20 sinuses. When ultrasonographic findings revealed mucosal thickening, complete filling, polyp or cyst, the agreements with radiographic findings were 24/30, 21/25, and 11/15, respectively. Negative ultrasonography agreed with negative sinusoscopic findings in 17/20 sinuses. When ultrasonographic findings revealed mucosal thickening, complete filling, polyp or cyst of the maxillary sinuses, the agreements with sinusoscopic findings were 26/30, 23/25, and 13/15, respectively. In comparison to radiological findings, the sensitivity of ultrasonography was 0.93 and specificity 0.60, and in comparison to sinusoscopic examination, sensitivity of ultrasonography was 0.93 and specificity 0.74. CONCLUSIONS: Ultrasonography can be used as a diagnostic method in the early diagnosis of sinus diseases. Compared to radiographic and sinusoscopic findings, it shows a high agreement in negative and positive findings, i.e., a high sensitivity and specificity.

Arachidonic acid metabolites and sinonasal polyposis. I. Possible prognostic value.

PURPOSE: The etiology of sinonasal polyps is sometimes obscure. This study was undertaken to evaluate the potential role of arachidonic acid metabolites (AAm) on recurrent polyposis. MATERIALS AND METHODS: Tissue production of prostaglandin E2 (PGE2), 6-keto-prostaglandin F1-alpha (PGI2), thromboxane A2 (TxA2), and leukotriene C4 (LTC4) by nasal mucosa was determined by radioimmunoassay in 27 patients with sinonasal polyposis (SNp) and in 10 volunteers. RESULTS: The group of patients with SNp with the evidence of recurrences in postoperative period (Group 1) showed significantly lower PGE2 concentrations than group of patients with SNp recurrences (Group 2). The differences in concentrations of PGI2 in mentioned groups were insignificant. In comparison with other groups, a group of patients who underwent surgery several times for SNp (Group 4) had a higher mean TxA2 concentration. The LTC4 concentrations were the highest in groups of patients where SNp recurrences were observed. When the incidence of polyposis recurrences (within 18 months after surgery) was correlated with the level of LTC4 production at the time of surgery, the rate of recurrence was significantly higher in patients with increased LTC4 level than in those with normal LTC4 levels. CONCLUSIONS: LTC4 might have a prognostic value. The possible role of AAm in occurrence of SNp is apparent and suggests possible role for medical intervention.

A-mode diagnostic ultrasound of maxillary sinuses: possibilities and limitations.

The diagnostic possibilities and limitations of A-mode ultrasound of maxillary sinus diseases are presented. A group of 219 subjects suffering from various sinus diseases was examined. All cases were analyzed in parallel by means of X-rays, sinoscopy and ultrasonography. The investigated group was divided into seven subgroups, according to clinical entity (polypoid degeneration, polyps, cysts, et cetera). The comparison of the three techniques was made for each clinical entity. Some divergent findings that can be reached by these techniques were explained from the clinical point of view as well. The ultrasound A-mode technique plays a complementary role in the diagnostic process of maxillary sinus diseases. The main advantages of ultrasound technique are its harmlessness and non-invasivity.

CO2 laser anterior turbinectomy in the treatment of non-allergic vasomotor rhinopathia. A prospective study upon 78 patients.

Preliminary results obtained in the treatment of non-allergic vasomotor rhinopathia by CO2 laser are presented. A group of 78 subjects, 35 males and 43 females, aged 18-48 years, mean age 27.6 years, were followed: subjective assessment of nasal breathing quality, anterior rhinomanometry, cytologic findings and saccharine test of nasal clearance. The parameters were observed preoperatively and after surgery. A 400 CO2 Surgical Laser Coherent Medical was used (power density, 140 w/cm2). The beam was applied upon the upper medial quadrant of the head of inferior turbinate by a continuous pulse (7-10 sec) through a Carl Zeiss surgical microscope, at a 10x magnification and focal length of 400 mm. The mean preoperative values of the anterior rhinomanometry were 0.669 and 0.851 Pa sec/ccs for inspiration and expiration, respectively. After the surgery, the mean values were even better, i.e. 0.361 Pa sec/ccs for inspiration, and 0.456 Pa sec/ccs for expiration. The morphological and functional conditions of nasal mucosa were also examined. The former was evaluated using cytologic smears of the nasal mucosa layer, and the latter by the saccharine test of nasal clearance. Normal cytologic findings were found preoperatively in 87% of all cases studied. Saccharine test was normal in 67% of cases. After laser surgery, the cytologic findings and saccharine test results were normal in 92% and 89% of cases, respectively. The subjective patients' assessment of nasal patency pointed to obvious success in 41 out 45 subjects treated.

Rhinomanometrical findings after septoplasty in children.

40 children of both sexes, aged 5-12, with deviations or fractures of the nasal septum were tested. These children were selected for septoplasty on the basis of anamnestic data, ENT examination and anterior rhinomanometry with and without anamnestic data. The control group consisted of 15 children, of approx. the same age and sex distribution, with normal nose breathing and rhinomanometrical findings. The operated group underwent clinical and rhinomanometrical examination 3 and 12 months after surgery, and the control group 12 months after the initial examination. Septoplasty was performed under general anaesthesia with locally applied vasoconstrictors. The results showed that rhinomanometrical resistances prior to surgery were significantly higher in all the subjects in the operated group than those in the control group. Rhinomanometrical resistances were lower in 29 operated cases 3 months after septoplasty than before septoplasty, and significantly lower in 32 operated cases 12 months after septoplasty. Rhinomanometrical resistances in the operated group 12 months after surgery were a little higher than those in the control group 12 months after the initial examination. Failures and complications after septoplasty are commented upon, as is their influence on rhinomanometrical resistances.