Contemplation of the Surgical Normogram of Lateral Rectus Recession for Exotropia Associated with Superior Oblique Palsy

PURPOSE: To suggest a surgical normogram for lateral rectus recession in exotropia associated with unilateral or bilateral superior oblique muscle palsy (SOP). METHODS: We retrospectively reviewed the charts of 71 patients with exotropia who were successfully corrected over one year. Each patient had undergone unilateral or bilateral rectus recession associated with uni- or bilateral inferior oblique (IO) 14 mm recession, using a modified surgical normogram for lateral rectus (LR) recession, which resulted in 1 to 2 mm of reduction of LR recession. We divided all patients into 2 groups, the 34 patients who had undergone LR recession with unilateral IO (UIO) recession group and the remaining 37 patients who had undergone LR recession with bilateral IO (BIO) recession group. Lateral incomitancy was defined when the exoangle was reduced by more than 20% compared to the primary gaze angle. The surgical effects (prism diopters [PD]/mm) of LR recession were compared between the two groups using the previous surgical normogram as a reference (Parks' normogram). RESULTS: The mean preoperative exodeviation was 20.4 PD in the UIO group and 26.4 PD in the BIO group. The recession amount of the lateral rectus muscle ranged from 4 to 8.5 mm in the UIO group and 5 to 9 mm in the BIO group. Lateral incomitancy was noted as 36.4% and 70.3% in both groups, respectively (p = 0.02). The effect of LR recession was 3.23 +/- 0.84 PD/mm in the UIO group and 2.98 +/- 0.62 PD/mm in the BIO group and there was no statistically significant difference between two the groups (p = 0.15). CONCLUSIONS: Reduction of the LR recession by about 1 to 2 mm was successful and safe to prevent overcorrection when using on IO weakening procedure, irrespective of the laterality of SOP.

The Long-Term Effect of Part-Time Occlusion Therapy According to Compliance in Recurrent Intermittent Exotropia

PURPOSE: To evaluate the reoperation rate and the change of exo-angle according to compliance level of part time occlusion therapy in recurrent intermittent exotropia. METHODS: This retrospective study included 52 patients of recurrent intermittent exotropia who followed up more than 5 years after their first operation. They were ordered part time occlusion therapy for recurrent exotropia. The patients were divided into 4 groups according to the level of compliance of part time occlusion therapy ('excellent', 'good', 'fair', 'poor'). We evaluated the reoperation rate in 5 years after the first operation and the change of exo-angle from the early recurrent time according to compliance levels. RESULTS: The reoperation rate within 5 years after the first operation of 'excellent' and 'good' compliance groups was lower than that of 'fair' and 'poor' groups (33.3, 26.3, 73.7 and 45.5% respectively) and the degree of exo-angle progression from the early recurrent time of the 'excellent' and 'good' compliance groups was less than that of 'fair' and 'poor' compliance groups, both results of which were statistically significant (p=0.02, 0.03). CONCLUSIONS: Part time occlusion therapy in recurrent intermittent exotropia has good long-term effects of decreasingreoperation rates in patients with a high level of compliance.

Postoperative Recovery of Stereopsis in Longstanding Adult Constant-Horizontal Strabismus

PURPOSE: To evaluate postoperative binocularity after surgical correction of longstanding constant-horizontal adult strabismus without both stereopsis and previous surgery. METHODS: Subjects included 43 adults over 18 years of age, who had constant-horizontal strabismus for more than 10 years without previous surgery and stereopsis. The patients were composed of 30 exotropes and 13 esotropes. Patients with a corrected visual acuity less than 20/40 in the deviating eye were excluded. After correcting for refractive error, the angle of deviation was measured, and pre- and postoperative stereopsis was assessed with the Titmus fly test and Randot stereo test. The relationship between duration of deviation and recovery of stereopsis or obtained stereoacuity were evaluated. RESULTS: The mean preoperative angle of deviation was 49.8+/-12.56 PD in exotropes and 34.7+/-12.41 PD in esotropes. All patients showed suppression of the deviating eye at distance and near before surgery. Postoperatively all patients showed orthophoria within +/-8 PD. Stereopsis was obtained in 80% of exotropes and in 30.8% of esotropes. The mean postoperative stereoacuity was 449.2+/-815.29 seconds of arc (sec) in exotropes and 1000+/-1336.66 sec in esotropes. However, there was no significant relationship between the duration of deviation and the obtained stereoacuity (p>0.05), or between the duration of deviation and the recovery of stereopsis (p>0.05). CONCLUSIONS: Adults with longstanding constant-horizontal strabismus more than 10 years obtained stereopsis with good quality after surgical correction. The recovery of stereopsis was much better in exotropes than in esotropes. Recovery was not influenced by the duration of deviation.

The Morphological Differences of Proprioceptors in Extraocular Muscles among Congenital, Acquired Exotropia and Congenital Nystagmus

PURPOSE: To evaluate morphological differences in proprioceptors in extraocular muscles between congenital exotropia, acquired exotropia and congenital nystagmus. METHODS: Nine medial recti including the myotendinous junction were resected using medial rectus resection in three congenital and five acquired exotropia patients. Two medial recti and two lateral recti were resected using the modified Kestenbaum procedure in two congenital nystagmus patients. The muscle tissues were examined under a light microscope following examination with a transmission electron microscope. RESULTS: In the congenital exotropia group, the electron microscopic findings showed degenerative changes in proprioceptors, such as decreased microtubules, axonal shrinkage and decreased myelin thickness. In the acquired exotropia group, the neural structures in the myotendinous junction were well maintained. There were no neural structures in the myotendinous junction in the congenital nystagmus group. CONCLUSIONS: Depending on the type of strabismus, there may be morphological differences in proprioceptors of extraocular muscles.

Endogenous candidal endophthalmitis associated with flame burn injury and advanced gastric cancer

PURPOSE: We report a case of candidal endophthlmitis developed in a patient with advanced gastric cancer who recently injured by flame burn. He was treated successfully with intravitreous and intravenous antifungal agents. METHODS: A 40-year-old man visited with complaints of decreased binocular visual acuity 7 weeks after third degree flame burn injury to 25% of body surface. Indirect ophthalmoscope showed findings of fungal endophthalmitis and upper gastro-intestinal endoscopic examination diagnosed of fungal esophagitis and advanced gastric cancer. He was treated with amphotericin B intranvitreously and fluconazole and amphotericin B intravenously. RESULTS: His visual acuity was improved to 20/50 (OD), 20/30 (OS) following 4 weeks after treatment and intraocular inflammation was decreased. After 5 months, he recovered his visual acuity as 20/25 (OD), 20/20 (OS), and had no inflammation in anterior chamber and vitreous.

The Effect of Corticosteroids on Myopic Regression after Laser in Situ Keratomileusis

PURPOSE: This study was to evaluate the effect of topical steroid treatment on eyes that showed myopic regression after LASIK. METHODS: A total of 26 patients (33 eyes) who showed myopic regression more than 1.00 diopter(D) confirmed by topography and pachymeter, were prospectively treated with 1% topical prednisolone acetate. Manifest refraction, Snellen uncorrected visual acuity and intraocular pressure(IOP) were measured before and after treatment. Topical steroids were administered every 2 hours for 3 days and 4 times a day for 11 days. Then the treatments were tapered in the eyes that showed over +0.50 D reversal of myopic regression. But it was immediately stopped in those eyes that showed no improvement or IOP increase. Pachymeter was taken in the improved group 4 weeks after the treatment. RESULTS: Fifteen eyes (45.5 %) showed over +0.50 D reversal of myopic regression(mean +/- SD +1.21 +/- 0.74 D, range: +0.50 ~ +2.75) and the uncorrected visual acuity increased (20/45 before treatment, 20/27 after treatment, p<0.01). The mean corneal thickness decreased (501.9 +/- 18.5 micrometer before treatment, 492.2 +/- 19.2 micrometer after treatment, p<0.01). Refractive effect of the steroid treatment remained stable with four of the eight eyes that could be followed up over six months. IOP was elevated in 3 eyes, but readily normalized with pressure-lowering agent. CONCLUSIONS: Topical steroid treatment for myopic regression after LASIK is partially effective and safe. It is recommendable to use topical steroid prior to performing surgical retreatment.