Recurrent Occlusion of Laser Iridotomy Sites After Posterior Chamber Phakic IOL Implantation

We report a case of recurrent occlusion of laser iridotomy (LI) sites after a Visian ICL (Implantable contact lens version 4, Staar Surgical AG, Nidau, Switzerland) implantation. A 45-year-old woman had bilateral ICL implantation after placement of two peripheral LI sites in each eye to prevent pupillary block. At one month after the operation, severe narrowing or occlusion of four LI sites occurred. After this, although she received four additional LIs at postoperative months 1, 6, 9 and 10 in both eyes, the narrowing or occlusion recurred. Mild chronic anterior chamber inflammation was observed intermittently throughout the follow-up period. We performed clear lens extraction in both eyes (at postoperative month 11 in the left eye and month 26 in the right eye) due to recurrent occlusion of the LI sites and excess trabecular meshwork pigment deposition presumably caused by the four repeated LIs. Recurrent obstruction of LI sites can occur after ICL implantation. These problems were unresolvable despite four repeated laser iridotomies. The risks associated with anterior uveitis must be considered when planning an ICL implantation.

The Measurement of Therapeutic Effect of Bendaline(R) in Early Cataract using with Scheimpflug Camera

The Scheimpflug photography was used to evauate objectively changes in lens opacity at a month interval in 143 eyes of 78 patients affected by early cataract. from Dec. 1993 to Dec. 1994. A total of 48 patients were treated daily with 1.5g bendazac-lysine, and 30 patients constituted the control group. We checked visual acuity and analyzed change of lens opacity by using axial densitometry and retroillumination of Scheimpflug photography after Bendaline(R) medication up to 9 months After treatment, improvement or no change of subjective visual acuity was observed in 65 eyes(78.3%) of treated group, whereas decrement in 35 eyes (58.3%) of control group. In the axial densitometry, the nuclear opacity began to improve after 3 months of medication and opacities of lens between anterior supranucleus and posterior capsule were statistically significant improved after 5 months of medication (p0.05). The result show that bendazac lysine may be effective in improvement of visual acuity and delay the formation of lens opacity in early cataract.

Clinical Significance of Nasal Step Index in Early Glaucoma

Nasal step index(NSI) is an index of light sensitivity of the nasal step area, the early sign of visual field defects in glaucoma. It represents the asymmetry between the upper-nasal and lower-nasal quadrant within 30 degree field. We applied this index to 66 eyes with normal visual field and 204 eyes with mild-to-moderate glaucomatous visual field defect (mean defect(MD)or=1.04), respectively. AUC values related to the validity of this study were NSI-1:0.38, NSI-2;0.44 and MD;0.83 in early glaucoma patients. But AUC values in high NFBI patients were NSI -1;0.50, NSI -2;0.50, MD;0.82. Therefore, NSI is shown to have lesser diagnostic value than MD in detection of early glaucoma in this study.

The Effect of Topical Verapamil in Q-Switched Nd:YAG Laser Induced Glaucoma Rabbits

To create an experimental glaucoma model in rabbit and to study the effect of elevated intraocular pressure (IOP) on rabbits ocular tissues, we treated trabecular meshwork of 7 adult pigmented rabbits with Q-switched Nd:YAG laser. And then we studied the IOP lowering effect of topical verapamil in experimental glaucoma model. The IOP and outflow facility were measured with an applanation pneumotonograph (Alcon, Texas). During sustained rap elevation, 50ul of 0.25% verapamil was instilled in one eye and normal saline in the fellow eye. The IOP was measured 1, 2, 4, 8 hours after instillation. The measurement was repeated twice at 2 weeks interval. After 5 weeks, the IOP increased from an average baseline IOP of 16.6mmHg to 25.51mmHg, an increase of 55.6%. The outflow facility was decreased from 0.21 microliter/min/mmHg to 0.09 microliter/min/mmHg. There were statistically significant reductions in IOP in both verapamil and placebo-treated eyes(p<0.05). The reduction was greater in verapamil-treated eyes than in placebo-treated eyes(p<0.05). Maximal reduction of IOP was observed 2 hours after single-drop of verapamil, with significant reduction of IOP up to 4 hours duration(p<0.05). During the observation period of this study, cupping of the optic nerve head developed. Histopathologic examination revealed extensive scarring of the anterior chamber angle structure. There are marked hyaline degeneration of retinal ganglion cells in temporal retina.

Comparisons Between Nerve Fiber Bundle Index and Mean Defect in Early Glaucoma

Nerve fiber bundle index(NFBI) is a new index which detects visual field depression in 21 nerve fiber bundle zones, reflecting the topographical arrangement of visual field defects. We applied this index to 39 eyes with normal visual field and 131 eyes with early glau-comatous field defect(mean defect