Comparison of Frequency Doubling Technology Perimeter and RNFL Photography for Early Diagnosis of Glaucoma

PURPOSE: To compare the frequency doubling technology perimeter (FDT) with retinal nerve fiber layer (RNFL) photography as a tool for the early detection of glaucoma. METHODS: Ninety-eight eyes of 98 patients were evaluated over a period of 3 months. According to the results of RNFL photography and FDT, Patients were divided into four groups based on the results of RNFL photography and optical coherence tomography (OCT). A comparison of the RNFL thickness of each group was performed using the OCT results. RESULTS: RNFL thickness in the group with abnormal FDT and normal RNFL were significantly decreased from those in the group with normal FDT and RNFL photography at the 6, 7 and, 10 o'clock area (p<0.05). CONCLUSIONS: There were statistically significant differences in the RNFL thickness between the group with abnormal FDT and normal RNFL photography, and the group with normal FDT and RNFL photography within the limited areas. These results imply that FDT is more useful for the early detection of glaucoma than RNFL photography.

Accuracy of Partial Coherence Interferometry in Intraocular Lens Power Calculation

PURPOSE: To evaluate the accuracy and the influencing factors of partial coherence interferometry in intraocular lens (IOL) power calculation for cataract surgery. METHODS: In 86 eyes of 69 patients who had undergone cataract surgery, we measured axial length using both IOLMaster and contact type ultrasonography, calculated the target refraction with SRK II formula and compared the result with the measured value after operation. We also evaluated the factors influencing the accuracy of the power calculation such as age, sex, type of cataract, severity of nucleosclerosis, corneal power, and preoperative refraction. RESULTS: In IOLMaster and contact type ultrasonography, the mean axial lengths were 23.70 +/- 1.27 mm and 23.55 +/- 1.28 mm (p<0.01), and the mean absolute errors (MAE) of refraction were 0.53 +/- 0.26D and 0.66 +/- 0.39D (p<0.01) respectively. The eyes of longer axial length showed larger MAE than those of shorter axial length (p=0.02). CONCLUSIONS: Partial coherence interferometry was more accurate than contact type ultrasonography in IOL power calculation. The factor associated with the accuracy of partial coherence interferometry was the axial length.

Long-term Follow-up Results of Glaucoma Triple Procedures in Patients with Angle-closure Glaucoma

PURPOSE: To evaluate the long-term clinical efficacy for glaucoma triple procedures of angle-closure glaucoma. METHODS: The author reviewed retrospectively 30 eyes (Group A) which had undergone triple procedures for coexisting angle-closure glaucoma and cataract. The results were compared with those of 30 eyes (Group B) which had undergone trabeculectomy for angle-closure glaucoma and 25 eyes (Group C) which had undergone glaucoma triple procedures for open-angle glaucoma. All patients were followed up for more than 3 years after operation at the Department of Ophthalmology in a hospital from November 1990 to December 1999. RESULTS: The mean intraocular pressures at the last follow-up were 16.1mmHg, 20.9mmHg and 19.7mmHg and the surgical success rates were 83.3%, 63.3% and 68.0% in the triple procedure group of angle-closure glaucoma, trabeculectomy-alone group and triple procedure group of open-angle glaucoma respectively. CONCLUSIONS: Triple procedures in angle-closure glaucoma showed good long-term results in IOP control compared with the trabeculectomy-alone group in angle-closure glaucoma.

Ultrasound Biomicroscopic Changes after Laser Iridotomy or Trabeculectomy in Angle-closure Glaucoma

This study was performed to demonstrate the ultrasound, biomicroscopic and dimensional changes of angle structure after laser iridotomy (LI) and primary trabeculectomy (PT) in primary angle-closure glaucoma (PACG). Angle-opening distance at a point 500 (m from the scleral spur (AOD500), trabecular-iris angle (theta1), trabecular ciliary process distance (TCPD), ciliary process-iris angle (CPI), iris thickness (ID1, ID3), length of iris-lens contact distance (ILCD) and anterior chamber depth (ACD) were assessed before and after each procedure. Thirteen patients with LI and 16 with PT were prospectively enrolled. There were statistically significant increases in AOD500, theta1, and ILCD in both groups. CPI was decreased in both groups. ACD, TCPD, and iris thickness were not changed significantly. The changes in angle configuration after LI or PT may result more from alterations in aqueous pressure gradients across the iris and the changes of configuration were greater in the iris roots without rotation of ciliary body. However, we didn't find any significant differences in the changes of parameters between the two procedures.

Toxic Corneal Reaction Induced by Distilled Water Infused during Cataract Operation

PURPOSE: To report a case of toxic corneal reaction induced by accidentally infused distilled water into the anterior chamber during cataract operation. METHODS: 67-year-old female patient was admitted due to corneal edema and opacity which had been developed instantly by distilled water infused into anterior chamber during cataract operation at a private eye clinic. Cataract surgery was performed after 1 week, and the patient was treated with 5% NaCl solution and artificial eyedrop. RESULTS: On the sixth month after operation, the corneal edema and opacity were decreased remarkably. CONCLUSIONS: When acute corneal edema is developed during cataract operation, the surgeon should stop the procedure and examine all intraocular solutions and irrigation fluids. The prognosis must be estimated after use of hypertonic saline solution at least 6 months.

Long-term Results of Primary Trabeculectomy in Glaucoma

PURPOSE: This study was carried out to identify the usefulness of mitomycin C (MMC) used in trabeculectomy. METHODS: We retrospectively reviewed the medical records of 47 eyes of 37 patients who underwent primary trabeculectomy with mitomycin C (MMC group). Thirty four eyes of 30 patients underwent primary trabeculectomy without MMC (control group) from January 1991 to July 1996 at Chonnam National University Hospital. RESULTS: The mean intraocular pressure(IOP)'s at the last follow-up were 17.30+/-5.70mmHg and 18.96+/-7.57mmHg in MMC and control group, respectively. The mean numbers of postoperative anti-glaucoma medications were 0.89+/-0.89 and 1.26+/-0.66 in MMC and control group, respectively. By Kaplan-Meier survival analysis, the survival rate of filtration was higher in MMC group than control group up to postoperative 60 months. However, the rate was reversed after 60 months. Postoperative complications in MMC group were cataract, hypotony, shallow anterior chamber, hyphema, bleb leakage, bleb infection and hypotonic maculopathy. CONCLUSIONS: MMC was effective in IOP-control in primary trabeculectomy, but there was no significant difference in long-term IOP-lowering effect compared to control group. However, there were more serious complications in the MMC group compared to control group. Therefore MMC should be used selectively.

Ultrasound biomicroscopic dimensions of the anterior chamber in angle-closure glaucoma patients

In order to evaluate the morphologic types of appositional angle-closure glaucoma, biometric measurements were made in angle-closure glaucoma patients using Ultrasound biomicroscopy (UBM). Twenty-six patients with primary angle-closure glaucoma and 21 cataract patients with as a control group were examined. The angle-closure glaucomatous eyes were classified as type B in which the angle closure started at the bottom of the angle and type S in which the angle closure occurred in the vicinity of Schwalbe's line. The trabecular-ciliary process distance (TCPD, type B; 873.20+/-86.77 microm, type S; 832.52+/-82.96 microm, control; 1233.50+/-73.01 microm, p = 0.000) and the angle opening distance (AOD500, type B; 89.75+/-63.27 microm, type S; 88.85+/-72.95 microm, control; 304.40+/-104.30 microm, p = 0.000) were significantly shorter in patients with angle closure vice control group. No significant difference were noted in the three groups of patients in regards to iris thickness or ciliary process-iris angle. In this study, we have demonstrated that there are two types of appositional angle-closure and have shown the forward rotation of the ciliary process without changes of the ciliary process-iris angle in cases of angle-closure glaucoma.

Acrysof(R) and Polymethylmethacrylate Intraocular Lens Implantation in Diabetic Patients

OBJECTIVE: To determine the efficacy of Acrysof(R) intraocular lens (IOL) compared to PMMA IOL about visual acuity & postoperative complications (eg. posterior capsular opacification) in diabetic patients. PATIENTS AND METHODS: We retrospectively reviewed the medical records of 18 patients (21 eyes) which underwent cataract extraction with Acrysof (R) IOL implantation and 58 patients (65 eyes) with PMMA (polymethylmethacrylate) IOL implantation from January 1996 to December 1999 at Chonnam National University Hospital. RESULTS: Postoperative best corrected visual acuity of above or equal to 0.5 was seem in 66.7% in acrysof (R) group, and in 73.9% in PMMA group at 6 months follow-up. Postoperative posterior capsular opacification was 33.3% and 49.2% respectively, and there was statistically significant difference in both group(p=0.021). CONCLUSIONS: Acrysof(R) intraocular lens can be used safely and reduce the rate of posterior capsular opacification in diabetic patients, which can make the positive effect on the treatment of the diabetic retinopathy after cataract surgery.

The Efficacy and Safety of Mitomycin C and Releasable Suture in Glaucoma Triple Procedure

PURPOSE: To evaluate the clinical efficacy and safety of short-term application of mitomycin C and releasable scleral flap sutures. METHODS: The clinical outcome and complications were evaluated in 62 eyes undergone glaucoma triple procedure(Group A: with mitomycin C and releasable suture, Group B: with mitomycin C only, Group C: with releasable suture only, Group D: without mitomycin C and releasable suture). RESULTS: The mean postoperative intraocular pressure was relatively lower in group A and B than that of group C and D(p=0.868). The most common complication was posterior capsular opacity, and other complications were cystoid macular edema, hypotony, choroidal detachment and bleb leakage. CONCLUSIONS: The glaucoma triple procedure using mitomycin C and releasable suture could be recommended to be safe and effective on controlling the early postoperative and long-term intraocular pressure for treating the patients with coexisting cataract and glaucoma, and the use of releasable suture could lower the incidence of postoperative complications such as hypotony.

Neovascular Glaucoma with Diabetic Retinopathy: Trabeculectomy and Nd:YAG Cyclophotocoagulation

PURPOSE: We carried out to determine the effectiveness of trabeculectomy and neodymium:YAG (Nd: YAG) cyclophotocoagulation in eyes with neovascular glaucoma from diabetic retinopathy. METHODS: We retrospectively reviewed medical records of patients who had undergone trabeculectomy or Nd:YAG cyclophotocoagulation from May 1992 to August 1997. RESULTS: The average drop in IOP was 24.6 mmHg in the trabeculectomy group and 17.3 mmHg in the transscleral cyclophotocoagulation group. Success rate was 69.2% in the trabeculectomy group and 21.4% in the transscleral cyclophotocoagulation group. Most common postoperative complication was hyphema (38.4%) in the trabeculectomy group and phthisis bulbi (21.4%) in the transscleral cyclophotocoagulation group. CONCLUSIONS: Trabeculectomy had higher success rate and less serious complications than transscleral cyclophotocoagulation. Transcleral cyclophotocoagulation may be considered as a treatment of neovascular glaucoma in the patients who have severe pain or poor general condition.

Suprachoroidal Hemorrhage with Retinal Detachment During Trabeculectomy in Aphakic Glaucoma

Suprachoriodal hemorrhage is rare but devastating complication associated with intraocular surgery. We know risk factors but it is difficult to predict the occurrence of suprachoroidal hemorrhage. We experienced a case of suprachoriodal hemorrhage and retinal detachment during tabeculectomy which was treated with pars plana vitrectomy, silicone oil injection, and posterior sclerotomy, followed by reattachment of retina and choroid. When high risk patients for suprachoroidal hemorrhage are considered for surgery, adequate preoperative and perioperative management are mandatory.

Outcome of Excimer Laser Photorefractive Keratectomy Associated with Schirmer Test

To evaluate the clinical results of excimer laser photorefractive keratectomy(PRK)in dry eyes,the surgical outcomes &complications were studied in 68 eyes of 34 patients who had received PRK from June,1996 to December, 1997 at Department of Ophthalmology,Chonnam National University Hospital.The patients were divided into two groups according to the preoperative Schirmer test value(Group A :Schirmer test value 10 mm).In Group A,uncorrected visual acuity(UCVA)of better than 20/40 was 38(90.5%)eyes at 3 months and 39 (92.8%)of 42 eyes at last follow up.In Group B,UCVA of better than 20/40 was 23(88.5%)eyes at 3 months and 25 (96.2%)of 26 eyes at last follow up.Thirty six(85.7%)eyes and 23(88.5%)eyes achieved within +/-1 diopter of spherical equivalent at 3 months and thirty two(76%)eyes and 20(77%) eyes achieved within +/-1 diopter of spherical equivalent at last follow up in Group A &Group B respectively.The mean epithelial healing time was 3.38 +/-0.76 days in Group A and 3.23 +/-0.60 days in Group B. In conclusion,there is no statistically significant differences in postoperative results after excimer laser PRK between the two groups. Postoperatively tear deficiency symptoms such as foreign body sensation or feeling of dryness was more common symptoms in relative tear deficiency patients. Further long term follow up study should be done to identify the any other differences of two groups.

Clinical Comparison between Glaucoma Triple Procedure and Small Incision Cataract Surgery using Foldable silicone IOL

The purpose of this study was to evaluate the postoperative outcomes between the glaucoma triple procedure and the small incision cataract surgery using foldable silicone intraocular lens(IOL). This prospective randomized study comprised of 42 eyes which had the glaucoma triple procedure and 41 eyes which underwent small incision cataract surgery at chonnam University Hospital from May, 1994 to December, 1996. At least 3 months follow-up period was needed. Corrected visual acuity of 0.5 of better was obtained in 50% of triple procedure group and 88% of small incision cataract surgery group with the average lines of improved visual acuity of 5.6 and 7.2 respectively. There was no significant change in the refractive cylinder during the early postoperative period in both group. In the glaucoma triple procedure group, posterior capsular opacification(PCO) developed in significantly low incidence in the Mitomycin C using group and the incidence of PCO in eyes with IOL decentration was greater than in those without IOL decentration. In conclusion, patients who underwent glaucoma triple procedure using foldable silicone IOL showed excellent postoperative IOP control with success rate of 81%, rapid visual rehabilitation and refractive stability. We also found that glaucoma triple procedure with Mitomycin C was associated with lower incidence of PCO.

Vascular Risk Factors in Normal Tension Glaucoma

To evaluate the implication of vascular factor in normal tension glaucoma, authors performed color doppler imaging[CDI] for ophthalmic artery, central retinal artery and posterior ciliary artery in 21 eyes of 12 patients in normal tension glaucoma and 16 eyes of 11 patients in normal control group. We compared peak-systolic velocity[PSV], end-diastolic velocity[EDV], mean velocity[MV], resistance index[RI] and pulsatile index[PI] between the two groups. We evaluate the difference in parameters according to age, sex, systolic and diastolic blood pressure, past history of diabetes and hypertension, cup-disc ratio and visual field change. In normal tension glaucoma group, PSV, EDV and MV of ophthalmic artery and central retinal artery were significantly decreased and pulsatile index was significantly increased compared to those of normal group. Resistance index was also increased in normal tension glaucoma group, but statistically not significant. All parameters of posterior ciliary artery had no significant difference between the two groups. Age was related positively to pulsatile index and resistance index of central retianl artery and diastolic blood pressure was related positively to resistance index of ophthalmic artery. Cup-disc ratio was related negatively to PSV and EDV of ophthalmic artery. Above results imply that blood flow velocity decreased by increasing resistance factor in normal tension glaucoma, therefore local vascular factor might be related to the development of the normal tension glaucoma and affected by age, blood pressure and cup-disc ratio change.

Clinical Evaluation of the Glaucoma after Penetrating Keratoplasty

We retrospectively evaulated the frequency and risk factors of glaucoma after penetrating keratoplasty by reviewing charts of 96 patients(112eyes) who received the penetrating keratoplasty from May 1992 to Novermber 1995 at Chonnam Universty Hospital. Intraocular pressure was increased over 21mmHg in 18 eyes after surgery. Underlying disease of them were graft failure (5 eyes), bullous keratoplasty(5 eyes), corneal ulcer(5 eyes), trauma(3 eyes). Ten eyes(55.5%) were glaucomatous preoperatively. Eight eyes(44.4%) were phakic, 7 eyes(38.9%) aphakic, and 3 eyes(16.7%) pseudophakic. Ten eyes(55.5%) underwent only penetrating keratoplasty, 4 eyes(22.2%) vitrectomy at the time of penetrating keratoplasty, and 4 eyes(22.2%) combined cataract extraction. The eyes with previous history of glaucoma(19 eyes) had higher incidence of increased intraouclar pressure than those 93 eyes with no glaucoma history(P<0.0001). Aphakic eyes(21 eyes) had higher incidence of glaucoma than phakic eyes(80 eyes)(p<0.05).

Clinical Evaluation of the Graft Rejection after Penetrating Keratoplasty

In order to evaluate risk factors (sex, age, preoperative diagnoses, graft size, neovascularization of the recipient cornea, bilaterality, history of the previous graft failure, doner corneal preservation method, phakic status, glaucoma and enucleation time after death) influencing graft rejection, we reviewed 96 eyes underwent penetrating keratoplasty at the Chonnam University Hospital from May 1992 to December 1995, retrospectively. The rate of the graft rejection in penetrating keratoplasty was 34.3% (33 eyes). In detail, graft rejection occurred in 16 eyes(47%) among 34 vascularized corneas of recipient(R=18.0, P=0.000), 23 eyes(69.7%) among 33 vascularized orneas of donor side after operation (R=0.3, P=0.010), 5 eyes(35.7%) among 14 bilateral grafts, 4 eyes (57.1%) among 7 eyes having a history of graft failure, 6 eyes(40.0%) among 15 aphakic eyes(R=3.84, P=0.033), and 14 eyes among 32 eyes enucleated longer than 6 hours after death (R=10.1, P=0.002). In contrast, graft rejection occurred in 13 eyes (76.5%) among 17 postoperative glaucomatous eyes and in 20 eyes (25.3%) among 79 postoperative non-glaucomatous eyes, there was no statistically significant difference between two groups(P>0.05). These results suggest that neovascularzation of the either donor or recipient cornea, aphakic status of the recipient eyes, and enucleation time longer than 6 hours after death are high risk factors for graft rejection.

Clinical Evaluation of Behcet`s Disease Report of 85 Cases

To evaluate the clinical characteristics of Behcet`s disease, we reviewed the clinical record of the patient visited Chonnam University Hospital from January, 1987 to December, 1995. Among all 85 patients, the majority of them were in the fourth decade (42.4%) and 49 patients (58.9%) were female. Oral ulcer (81.2%) was the most frequent initial symptom. According to the criteria established by the Behcet`s Disease Research Committee of Japan, incomplete type was the ost common (43.5%) and the most frequent major and minor symptom was oral ulcer (95.3%) and arthritis (21.2%), respectively. Ocular lesions ppeared in 39 (45.9%), and 19 patients (48.7%) had two or more ocular esions. The most common symptom was iritis (70.7%) and male was more commonly affected than female. The mean interval between initial symptom and ocular symptom was 45.8 months. Among 43 eyes of 26 patients with follow-up of 3 months or more, 14 (32.6%) showed an impairment of two or more lines in visual acuity and 21 (48.8%) eyes had inal visual acuity of 0.3 or less. As similar to other reports, this result suggests Behcet`s disease is achronic, inflammatory disorder characterized by poor visual prognosis.

Comparision of Ocular pain Between Topical and Retrobulbar Anesthesia for Cataract Surgery

We analysed a perceiving pain at each step (8 step: traction suture, wound incision, anterior capsulotomy, phacoemulsification, irrigation and aspiration, intraocular lens (IOL) implantation, wound suture, subtenon's injection) of cataract surgery by using visual analogue scale (0-10), prospectively. One hundred cases of cataract surgery were performed from November 1995 to March 1996 at Chonnam national university hospital and topical or retrobulbar anesthesia prior to cataract surgery was applied to each 50 patients. There was no difference of age, sex, running time for surgery, and incision method between topical and retrobulbar anesthesia. Pain scores at phacoemulsi fication. irrigation and aspiration, and subtenon's injection were higher than those at other steps in both types of anesthesia. However, a major range of pain scores at each step except of subtenon's injection was mild (1-3). In topical anesthesia, pain score was higher than retrobulbar anesthesia, but there was no statistically significant difference except a step of subtenon's injection. In conclusion, topical anesthesia might be an adequate anesthetic method for cataract surgery.

Clinical Study on Combined Phacoemulsification and Intraocular Lens Implantation/Trabeculectomy with Mitomycin C

This study was undertaken to evaluate the outcome of combined phacoemulsification, intraocular lens implanation, and trabeculectomy with Mitomycin C. We reviewed 39 eyes in 36 consecutive cases who had been undergone triple procedure for coexisting cataract and glaucoma from January 1993 to October 1995 at Chonnam university hospital. The mean follow-up period was 8. 8 months. Preoperatively, most patients had a visual acuity of worse than 0.4, but the visual acuity improved postoperatively in 20 eyes (51.0%) achieving the visual acuity better than 0.5 at 6 months after the surgery. The mean preoperative intraocular pressure was 31.1 +/- 12.9mmHg, and the mean postoperative IOP was 16.5 +/- 5.4mmHg at 6 months follow-up. The mean number of antiglaucoma medication was 1.87 preoperatively, and 0.28 postoperatively. The postoperative complications were posterior capsular opacity (7 eyes), hyphema (2 eyes), shallow anterior chamber (3 eyes), transient hypotony without macular edema (2 eyes). There was no statistically significant difference in intraocular pressure control at different concentration of Mitomycin C (0.2 and 0.4mg/ml). We conclude that the use of Mitomycin C in combined procedure provides good short-term(6 months) results regarding intraocular pressure control and visual recovery.

Effect of Hypolipidemic drug on Diabetic Retinopathy

The effect of improving hypercholesterolemia on non-proliferative diabetic retinopathy have been evaluated in 18 patients, 34 eyes, with noninsulindependent diabetes mellitus. The patient group took 20mg of lovastatin daily for one month and after then 40mg of lovastatin daily for two months. The control group, 14 eyes, took placebo for 3 months. After follow-up of 6 months, the serum cholesterol concentration was decreased by 21% (from 301.35 +/- 38.48 to 232.97 +/- 19.73mg/dl). The visual contrast sensitivity funtion was improved significantly on the statistics (p=0.005) as compared with the control group. The corrected visual acuity was improved in 11 eyes(32.4%) and retinal lesion was decreased in 10 eyes (29.4%). But they were statistically insignificant. This result suggests lowering the serum cholesterol may make a positive effect on non-proliferative diabetic retinopathy of noninsulin-dependent diabetes mellitus with hypercholesterolemia by means of improving visual contrast sensitivity function.