Sensitivity and Specificity of Qualitative Signs to Detect Glaucomatous Optic Nerve Damage

Quantitiative evaluation of optic disc parameters such as neural rim area requires relatively sophisticated instruments and time consuming methods which are not generally available for the average ophthalmologist. This study was performed to determine which qualitative sign of optic disc distinguishes best between eyes with and without early glaucomatous visual field defects. Using color polaroid photographs we examined qualitative signs in 207 optic discs of 207 patients with primary open-angle glaucoma and in 158 optic discs of 158 normal subjects matched for age and refractive error. In the group with mild (mean deviation(MD) ; better than -5dB, group 1) to moderate (MD; -6~-10dB, group 2) glaucomatous visual field defects, the best results of specificity and sensitivity were achieved using alterations in the configuration of neural rim width (group 1; Specificity =70.3%, Sensitivity =93.4%), while abnormally large parapapillary chorioretinal atrophy, thinnest neural rim width outside the temporal horizontal sector, and presence of zone beta were signs with relatively high specificity and high sensitivity. In the group with advanced (MD; worse than -11 dB, group 3) visual field defects, thinnest neural rim width outside the temporal horizontal sector was the best sign to distinguish between normal and glaucoma eyes. Signs with high specificity and low sensitivity were optic disc hemorrhage, bayonetting of vessel and baring of circumlinear vessel. These results suggest that alterations in the configuration of neural rim width and parapapillary signs were valuable for early diagnosis of glaucomatous optic nerve damage without sophisticated instruments.

Clinical Evaluation of Idiopathic Corneal Endotheliopathy

The idiopathic corneal endotheliopathy appears clinically as a corneal graft rejection, which has a linear corneal endotheliopathy and well responds to corticosteroid theraphy. Its cause may be associated with autoimmune reaction(Khodadoust AA, Attazadeh A, 1982). We experienced five patients with idiopathic corneal endotheliopathy, and evaluated its clinical characteristics and treatment. We performed slit lamp examination, the measurement of intraocular pressure of five patients who visited our hospital to evaluate the progressive visual disturbance due to idiopathic corneal endotheliopathy. All cases showed endotheliopathy with keratic precipitates, corneal epithelial edema and stromal edema at corresponding areas. The intraocular pressures were within normal range and a mild inflammation in anterior chamber was found in two cases. The immune rings were shown in two cases and herpes zoster blepharitis had appeared in one case. All cases had a good response to topical corticosteroid and acyclovir treatment. However, four cases were recurred even though well responded to treatment following recurrence. We suggest that the pathogenesis of idiopathic corneal endotheliopathy would be associated with herpes virus infection.

Measurements of Diameter and Area of Optic Disc with the Scale of the Volk Lens

The measurement of the area of the optic disc is important to classification of congenital anomaly of optic disc and diagnosis and following up of glaucoma. This study was performed to measure easily the diameter and area of the optic disc using the retinal scale of the Volk lens although recently the study was reported to measure the optic disc with computerized optic disc analysis system. We evaluated the measurement of the diameter and area of the optic disc of 31 patients(56 eyes) using the retinal scale of Volk lens and then corrected the magnification of central fundus photographs using Litmann's method. The mean refractive power and the mean axial length was -0.24 diopter(range -4.5 to 4.25 diopter), and 22.91 mm (range 20.5 to 26.1mm), respectively. The mean horizontal diameter, the mean verticaI diameter, and the mean area of optic disc was 1.75 +/- 0.18mm, 1.90 +/- 0.19mm, and 2.62 +/- 0.50mm2, respectively. We think that the measurement of the optic disc area with Volk lens is useful method in following up of cup-disc ratio in outpatient basis.

Hypotony After Trabeculectomy with Mitomycin C

The purpose of this study is to evaluate the influence of clinical factors on the development of postoperative hypotony, and also to determine whether the occurrence of hypotony has any effect on the outcome of trabeculectomy with intraoperative mitomycin C. The authors retrospectively reviewed the outcome in 160 eyes of 112 patients who underwent tight scleral flap trabeculectomy with releasable sutures. Mitomycin C with 0.25 or 0.5mg/ml was applied for 3 or 5 minutes between the Tenon's capsule and the sclera. The mean follow-up period was 16.5 +/- 11.5 months. Success of the trabeculectomy was defined as intraocular pressure (IOP) 6-21 mmHg with or without medications. Hypotony(IOP

Optic Disc Measurements with Personal Computer in Normal Eyes

Quantification of the optic nerve head topography is getting more and more important in diagnosis, differential diagnosis and follow-up of optic nerve diseases, especially in glaucoma. This study was undartaken to measura optic disc parameters and further to determine side, gender, age, refractive errorrelated differences in the size and topography of the optic disc. The radius and angle of the optic disc and cup were measured every 30 degrees by a computer graphic program(Adobe Photoshop(TM)) in 142 eyes of 78 normal subjects(37 men, 41 women, mean age 47.2 +/- 14.2). The actual optic disc sizes were corrected based on refraction and anterior corneal curvature utilizing Littmanns method. Optic disc area averaged 2.47 +/- 0.48mm2, vertical disc diameter 1.86 +/- 0.18mm, horizontal disc diameter 1.68 +/- 0.18mm. Optic cup area averaged 0.56 +/- 0.28mm2, vertical cup diameter 0.68 +/- 0.28mm, horizontal cup diameter 0.84 +/- 0.27mm. Neuroretinal rim area averaged 1.90 +/- 0.37mm2 and rim width was widest in the inferior disc pole, followed by the superior, nasal, and temporal poles. A highly significant linear correlation between disc area and rim area was observed(r=0.81, p=0.0001) together with a correlation between the disc area and cup area(r=0.58, p=0.0001). Concerning optic disc area, side differences of 0.25mm2 or less were found in 60% and of 0.5 mm2 or less in 90%. Concerning neuroretinal rim area, side differences of 0.25mm2 or less were found in 73% and of 0.5mm2 or less in 90%. There were no significant correlations between these morphometric optic disc data and side, gender, age, or refractive error.

Releasable Suture after Tight Scleral-Flap Trabeculectomy with Mitomycin C

Mitomycin C may change the time course for effective releasable scleral-flap suture removal. The authors evaluated the safety and efficacy of releasable scleral-flap sutures in 83 eyes of 61 patients undergoing mitomycin C(MMC) filtering operation. Of these eyes, 38 underwent scleral-flap suture removal and these eyes were divided into three groups according to the timing of suture removal(Group 1: within 3 days after trabeculectomy, Group 2: from 4 to 14 days, Group 3: from 15 to 30 days). The pre-release IOP was 26.0 +/- 7.6, 23.8 +/- 8.5 and 18.4 +/- 4.6 mmHg, respectively. Immediately after releasable suture removal, the percent IOP reduction was 46 +/- 18, 46 +/- 17 and 30 +/- 20%, respectively. The percent IOP reduction after releasable suture removal was greater in the group 1 and group 2 compared with group 3(p<0.05). Mean follow-up period was 9.0 +/- 5.3, 14.4 +/- 7.2 and 12.6 +/- 7.6 months, respectively. Twelve eyes(80%), 12 eyes(100%), 10 eyes(91%) achieved successful control of final IOP of 21 mmHg or less with or without topical antiglaucoma medications, respectively. After releasable suture removal, the shallow anterior chamber was noted in 1 eye, 2 eyes and 1 eye, respectively. One eye developed a hypotony in the group 3. Adjunctive MMC therapy extended the period that releasable scleral-flap suture removal is effective beyond first 2 postoperative weeks. Also these results indicate that this method is efficient for IOP reduction and relatively safe.