Comparison between Upper and Lower Canalicular Tear Flow using Dacryoscintigraphy

We evaluated the relative tear flow in the upper and lower canaliculus using dacryoscintigraphy. 22 eyes were studied in 11 persons and the upper or lower punctums of both eyes were occluded with 0.3 or 0.4 mm diameter 1.75 mm long collagen plug and 13 of Technetium-99m sulphur colloid were placed in both eyes. Dacryoscintigraphy was performed in the upright position for 12 minutes. Using Pegasys. program, time-activity curve and T1/2 of radioisotope in the palpebral aperture were measured twice and the mean T1/2 was calculated. T1/2 values with the upper and lower canaliculus occluded were compared and analyzed. Of 22 eyes studied, 12 had more rapid tear transport in the upper canaliculus and 10 through the lower. The mean T1/2 of transport in the upper canaliculus was 703.2+/-789.2 seconds and 692.3+/-450.3 seconds in the lower. Tear drainage in the lower canaliculus was more rapid but this value was not found to be statistically significant (P=0.626 ). Therefore there was no significant difference between the upper and lower canalicular tear flow but individual variabilities. Considering these results, when punctum occlusion for the treatment of dry eye and reconstruction of canalicular laceration are performed we should equally weigh on both the upper and lower canaliculus.

The Effect of Botulinum Toxin Chemodenervation in Chronic Paralytic Strabismus

Botulinum toxin chemodenervation is widely used for the treatment of acute paralytic strabismus. We reviewed the effect of botulinum toxin chemodenervation for the treatment of chronic paralytic strabismus. Between 1996 and 1998, 13 patients with chronic paralytic strabismus were treated with botulinum toxin chemodenervation. The palsy of extraocular muscle persisted for at least 6 months. Each patient received an injection of 1.25 to 5 units of botulinum toxin[Botox]to the antagonist muscle of the paralytic muscle and two patients received injections two times. The follow-up was more than 6 months [mean 7.62 months].2 patients were treated with surgery of horizontal muscles and 3 patients were treated with muscle transposition surgery before injection. The mean preinjection deviation was 36.7PD and the mean strabismus angle after injection was 19.2PD and improving rate of the strabisbismus angle was 47.6%. The final deviations of 6 patients were within 10PD[46.2%]and 4 of 7 patients with final deviation above 10PD were treated with surgery later. Ptosis occurred in 4 patients[30.8%]and hypertropia occurred in 4 patients[30.8%]. In addition to the prevention of muscle contracture with botulinum toxin injection, it is likely that the therapeutic effect of botulinum toxin is produced by permanent alteration in the muscle and influence on the peripheral and central nervous system. Therefore botulinum toxin chemodenervation can be considered as a primary therapy or a subsequent therapy of surgery for chronic paralytic strabismus and further study is needed.

The Effect of Macular Translocation for T reatment of Subfoveal Lesion

To maintain the function of central vision from the sensory retina at the macular area, we performed macular trasnlocation for the treatment of subfoveal lesion. Laser photocoagulation hardly avoid central scotoma and surgical removal of neovascular membrane tends to result in poor visual outcome because of the unhealthy underlying retinal pigment epithelium. We performed macular translocation in four patients with subfoveal lesion using modified macular translocation technique. Surgical steps include trans pars plana vitrectomy, creation of a retinal detachment, scleral shortening, air-fluid exchange and gas injection. The results were the increased visual acuity in two patients and the improved symptom in two patients. Our result suggested that the macular translocation procedure may be considered as a therapeutic modality for the treatment of patients with subfoveal lesion.

The Clinical Review of Epithelial Tumors in the Lacrimal Gland

We retrospectively reviewed clinical and radiologic findings of 19 patients who had been diagnosed as epithelial tumors of the lacrimal gland histopathologically after biopsy and surgery at Shinchon Severance Hospital from April, 1991 to July, 1998 and evaluated their correlation to the pathologic diagnosis, treatment and prognosis. There were 7 men and 12 women with the mean age of 41.0+/-13.3 years. Histopathologically, there were 7 cases of adenoid cystic carcinoma, 1 case of adenocarcinoma, 1 case of malignant mixed tumor, 9 cases of pleomorphic adenoma, and 1 case of benign oncocytoma. In comparison with benign epithelial tumor of the lacrimal gland, the characteristic clinical findings of malignant epithelial tumor of the lacrimal gland were pain, limitation of motion, and diplopia[44.4%]. The mean duration of the symptoms of malignant epithelial tumor was shorter[10.3+/-6.6 months] than that of benign epithelial tumor[19.5+/-14.4 months]. In radiologic CT and MRI findings, there were characteristic bony destructions in malignant epithelial tumors of the lacrimal gland[55.6%] compared with benign tumors and poorly marginated outline of the tumor was noted in malignant tumors[44.4%] but not in benign tumors. Therefore, clinical and radiologic findings of epithelial tumors of the lacrimal gland were well correlated with the pathologic diagnosis and would attribute to early diagnosis of malignant tumors.