Normal Macular Thickness Measured Macular Mapping of OCT3

PURPOSE: The authors used the instrument, OCT3, to evaluate the reproducibility and map the macular thickness rapidly in normal subjects METHODS: Macular thickness was measured in 120 eyes of 62 normal subjects, aged 18 to 79 years, with the macular OCT3 map. There was no history of ocular disease in any of the subjects, and routine ophthalmoscopic examination results were normal. RESULTS: The coefficient value for macular thickness was lower than 2%, indicating that OCT3 provides reliable measurements. Macular thickness of normal subjects was 193.4 +/- 14.6 micro meter in the central ring, 273.0 +/- 14.8 micro meter in the inner ring and 238.2 +/- 15.6 micro meter in the outer ring. The nasal and superior quadrants of the inner ring and the nasal quadrant of the outer ring had higher thickness measurements than another. A decrease of retinal thickness was observed in the old group. However, gender did not have a significant effect on the values. CONCLUSIONS: Macular thickness analysis with OCT3 provided a detailed map of the macular thickness. This indicates that the method may provide a sensitive detection of pathologic thickening or thinning of the retina and suggests that the macular thickness decreases with age.

THE CLINICAL UTILITY OF POSITRON EMISSION TOMOGRAPHY FOR INITIAL DIAGNOSIS AND FOLLOW UP CHECK IN ORAL AND MAXILLOFACIAL CANCER PATIENTS

BACKGROUND: Positron Emission Tomography(PET) with [18F]-fluorodeoxyglucose (FDG) is a new imaging technique that has the advantage of imaging metabolic changes linked to malignancy. PET-FDG can provide a functional image of the regional biochemistry which may be more sensitive and accurate for detecting the presence of tumor in early stage. Recently, the clinical use of PET scan has been studied in many cancers but, there is a few clinical reports in oral and maxillofacial cancers. We have evaluated the ability of PET-FDG for initial diagnosis and detection of early subclinical recurrent malignancies in follow up check. PATIENTS AND METHODS: PET-FDG studies were performed in 33 patients from october, 1997 to september, 1998. 14 patients underwent PET-FDG evaluation for initial diagnosis and 19 patients for follow up check. RESULTS: Evaluated for initial diagnosis, PET-FDG was found to have an overall accuracy of 79%, sensitivity of 90%, specificity of 60%, positive predictive rate of 80% and negative predictive rate of 75%. Evaluated for follow up check, PET-FDG demonstrated accuracy of 84%, sensitivity of 91%, specificity of 75%, positive predictive rate of 83% and negative predictive rate of 86%. CONCLUSION: These data indicate that PET-FDG scan appears to be effective in initial diagnosis and detection of early recurrent oral and maxillofacial malignancies. The informations gained with PET-FDG can be included for essential treatment planning because of possibility of detection for early subclinical malignancies and distant metastases.

The Surgical Results of Medial Rectus Muscle Resection of Dominant Eye and Lateral Rectus Muscle Recession of Non-dominant Eye in Intermittent Exotropia

Intermittent Exotropia has been treated by various surgical methods such as bilateral medial rectus resection, lateral rectus recession and medial rectus resection of deviating eye, and bilateral lateral rectus recession. However, the outcomes of such operations are unsatisfactory because of high incidence of postoperative undercorrection and overcorrection. Authors have performed a surgical method which is the medial rectus muscle resection of dominant eye and lateral rectus muscle recession of non-dominant eye in 68 patients. Authors considered the outcome successful if patients achieve deviation between 10 PD of exophoria and 5 PD of esophoria, good stereopsis, no suppression and no manifest deviation. The success rate was 83.8% (57/68) and there was no overcorrection over 6 months follow-up. As postoperative complications, 5 cases of temporary turning of face and 3 cases of asymmetric palpebral fissure were seen. Therefore, these results suggest that medial rectus resection of dominant eye and lateral rectus recession of non-dominant eye in intermittent exotropia may be an alternative surgical method for intermittent exotropia. However, further studies are necessary to determine the exact surgical amounts and mechanism of this surgical method.

The Clinical Study of Retinal Detachment Associated with B ranch Retinal Vein Occlusion

The branch retinal vein occlusion is the second most common retinal vascular disease after diabetic retinopathy. Complications such as macular edema, retinal neovascularization, vitreous hemorrhage, epiretinal membrane may be associated. But, the retinal detachment may occur rarely in BRVO patients. We studied the clinical features of retinal detachment associated with branch retinal vein occlusion. We reviewed the medical records of 15 retinal detachment patients associated with branch retinal vein occlusion. Mean age was 54.7 years old and 10 patients(66.7%) were female. Hypertension was associated in 13cases(86.7%). The duration between the development of BRVO and the development of retinal detachment was shorter than 4 years in all cases and shorter than 2 years in 9 cases(60.0%). Retinal break was identified in 14 cases(93.3%), among which 13 cases(92.2%) were located inside the lesion of branch vein occlusion. The epiretinal membrane was frequently combined 8 cases(53.3%). The preoperative laser photocoagulation was done in 4 cases(26.7%). The primary surgical procedures included scleral buckling in 8 cases(53.3%), pars plana vitrectomy in 6 cases(40.0%), and scleral buckling with pars plana vitrectomy in 1 case(6.7%). Three cases(20.0%) required reoperations. The postoperative complications included the progression of cataract in 6 cases(40.0%), iatrogenic retinal tear in 3 cases(20.0%), epiretinal membrane in 2 cases(13.3%), and proliferative vitreoretinopathy in 1 case(6.7%). The anatomic retinal reattachment was achieved in 14 cases(93.5%) and the visual recovery in 11 cases(73.3%).

The Clinical Study of Macular Hole Retinal Detachment Associated with Peripheral Retinal Hole

Most of the macular hole retinai detachinents are limited to the perimacular area. Therefore, we must look for the peripheral retinal hole when the macular hole retinal detachment extends beyond equator. And the principle of operation should be on the peripheral retinal hole rather than macular hole. Authors studied the clinical feature of macular hole retinal detachment associated with the peripheral retinal hole. Among the 39 macular hole retinal detachment patients, peripheral hole was found in 12 patients (30.7%). Sex distribution was the same and mean age was 55.9 years old. Retinal detachment was not diagnosed for more than I month in 7 cases (58.4%). Nine cases (75.0%) were extensive retinal detachments extending beyond 3 quardrants. Nine cases (75.0%) had one peripheral hole and most of peripheral holes were found on the ternporal side. Associated diseases were cataract (5 cases, 38. 5%) and high myopia (5 cases, 38.5%). In 4 cases (33.3%) hole was found on the opposite side. Among the 12 macular hole retinal detachment patients, 11 operations were performed with the technique of gas injection and scleral buckling which lead to successful attachment in 5 cases (41.7%). Among the 7 cases in which reoperations were needed, 3 cases (42.9%) were recurred in 3 months. In 8 cases (66.7%) there were improvements of post-operative visual acuity.

PHOTODYNAMIC THERAPY FOR EARLY TONGUE CANCER

The standard methods of treatment in oral and maxillofacial cencer are surgery, radiotherapy and chemotherapy. But all of them can induce significant morbidities, surgery in this area can cause remarkable junctional and esthetic problems. The applications of photodynamic therapy(PDT) has been studying and trying in these days to minimize post-treatment complications. It can almost directly affect tumor cells except surrounding normal tissues, so we are able to reduce post-operative complications. But there can be a couple of complications after PDT, as like skin photosensitivity, so therapists must attend to its use and completely understand their mechanism before doing it. In our clinic, PDT was tried in an early tongue cancer patient using topically applied delta-aminolaevulinic acid (delta-ALA). The 64-year-old man was gargled with 5% delta-ALA 4 hours before irradiation. The previous punched biopsy was reported as well differentiated squamous cell carcinoma(T1N0M0). Light of 635nm wave-length from argon-pumper dye laser was used. Total 150J/cm2 was applied. After 10 days, PDT was applied again in a small suspicious area, 10 days after then, small area was excised and examined histologically. It was revealed as cancer free. Now, the patient was periodically checked up. Conclusively, PDT can be thought to be a acceptable alternative and promising method in treating of early oral and maxillofacial cancer.

THE UTILITY OF POSITRON EMISSION TOMOGRAPHY IN ORAL AND MAXILLOFACIAL CANCER

Positron emission tomography(PET) is a diagnostic method that creates high resolution, 3-Dimentional tomographic images of the distribution of positron emitting radionuclides in human body. Computed tomography(CT) and magnetic resonance imaging(MRI) are routinely used to delineate the presence and extent of primary and metastatic oral and maxillofacial malignancy. Because the CT and MRI criteria for malignancy depend upon morphology, these imaging techniques have limitations in their ability to identify malignant tissue when fascial planes are distorted or destroyed. PET has the advantage of imaging metabolic changes that appear to be linked to malignancy. Recently, PET has shown promise in the early detection of primary and metastatic oral and maxillofacial canter and has been used to evaluate the tumor response to chemotherapy and radiotherapy. We report cases of diagnosis of oral and maxillofacial cancers and review the literatures to determine whether PET is effective in identifying oral and maxillofacial tumors.

Implants in irradiated bone

Squamous cell carcinoma arising from residual odontogenic cyst: Report of a Case & Review of Literatures