Needle Revision with and without Mitomycin C for the Teatment of Failed Filtering Blebs after Trabeculectomy

PURPOSE: To evaluate the effects of needle revision (NR) with and without mitomycin C (MMC) for failed filtering blebs after trabeculectomy, and to identify risk factors for failure. METHODS: Thirty-one eyes whose intraocular pressure (IOP) did not decrease after cutting of scleral flap sutures were recruited. NR was performed with a 26-gauge needle under a slit-lamp. Immediately following NR, 15 eyes received subconjunctival injection of 0.002 mg (0.02 mg/ml) MMC at the adjacent conjunctiva. RESULTS: First NR was done at 1.3+/-1.2 months (range, 0.2~6.5 months) after trabeculectomy, and a mean of 1.6+/-1.6 NRs per patient were done. The follow-up period was 24.4+/-20.4 months (range, 6.0~87.4 months) after the last NR. Pre-NR mean IOP was 27.9+/-11.6 mm Hg and post-NR final IOP was 18.8+/-13.0 mm Hg (p=0.005). The success rate, defined as IOP 25 mm Hg showed a higher failure rate, though with no statistical significance (p=0.141 and p=0.173, respectively). CONCLUSIONS: NR followed by subconjunctival injection of MMC is an effective and safe method for the treatment of the failed filtering blebs after trabeculectomy. Trabeculectomy without adjunctive MMC and pre-NR IOP higher than 25 mmHg were risk factors for failure of NR.

Effects of Management on High Intraocular Pressure after Trabeculectomy

PURPOSE: To investigate the effect of stepwise procedures on high intraocular pressure (IOP) after trabeculectomy. METHODS: A retrospective review was coducted on the medical records of patients who underwent trabeculectomy between January 1997 and December 2002. at the Chungbuk National University Hospital. Analysis included 136 eyes from 118 patients who received at least 6 months of follow-up care (mean 22.4+/-18.1 months). High IOP during the early postoperative period was identified in 104 of the 136 eyes, and these were treated by the following methods in a stepwise manner: (1) cotton-tip application (a slow, steady eyeball pressure with a sterile cotton tip was favored), (2) scleral flap suture cutting (26-gauge needle), (3) needling of the bleb (without antimetabolites), (4) additional antiglaucoma medication. If none of the above management techniques was successful, the surgery was repeated. After cotton tip application or scleral flap suture cutting, patients were divided into the recovery group (IOP was reduced) and the non-recovery group. RESULTS: Success rates were 11.8% for cotton-tip application, 15.4% for scleral flap suture cutting, 0.7% for needling without antimetabolites, and 28.7% for additional antiglaucoma medication. The overall success rate was 80.1%. Pre-interventional factors associated with the non-recovery group were higher preoperative IOP (p=0.003) and diabetes (p=0.017). CONCLUSIONS: Four procedures were used, in a stepwise manner, to reduce IOP following trabeculectomy. IOP was found to decrease to desirable levels without the use of antiglaucoma medication in 27.9% of all subjects.

Visual prognosis of patients undergoing cataract extraction and its relationship with that of the contralateral eye

PURPOSE: This study is to evaluate the visual prognosis according to the ocular morbidity of the fellow eye in a national university hospital located in rural area. METHODS: We retrospectively reviewed the medical records of 390 eyes of 315 patients who had undergone cataract surgery. We assessed the change of postoperative visual acuity and the state of preoperative fellow eye. RESULTS: The age at cataract surgery was the highest in the sixties (29.2%) and seventies (27.7%). The patients older than 80 of age were 10.0%. Preoperative ocular co morbidities (23.3%) were diabetic retinopathy, glaucoma, corneal opacity, uveitis, etc. Preoperatively, 91.3% of all cases had a visual acuity of 0.4 or lower, but 3 months after surgery, 72.1% of all had 0.5 or better. At postoperative 3 months, 27.9% showed visual acuity of 0.4 or less and the ocular co morbidities were found in 67.0%. Preoperative visual acuity of less than 0.1 in the fellow eye was 10.2%. Preoperatively, 97.5% of these cases had a visual acuity of 0.4 or lower, but only 40% had 0.5 or better postoperatively. Preoperative and postoperative visual acuity were poor in patients whose preoperative visual acuity was less than 0.1 in the fellow eye. CONCLUSIONS: The age at cataract surgery was the highest in the sixties (29.2%) and seventies (27.7%). The patients older than 80 of age were 10.0%. Preoperative ocular co morbidities (23.3%) were diabetic retinopathy, glaucoma, corneal opacity, uveitis, etc. Preoperatively, 91.3% of all cases had a visual acuity of 0.4 or lower, but 3 months after surgery, 72.1% of all had 0.5 or better. At postoperative 3 months, 27.9% showed visual acuity of 0.4 or less and the ocular co morbidities were found in 67.0%. Preoperative visual acuity of less than 0.1 in the fellow eye was 10.2%. Preoperatively, 97.5% of these cases had a visual acuity of 0.4 or lower, but only 40% had 0.5 or better postoperatively. Preoperative and postoperative visual acuity were poor in patients whose preoperative visual acuity was less than 0.1 in the fellow eye.

Outcome of Fornix-Based Versus Limbus-Based Conjunctival Flaps in Trabeculectomy with Mitomycin C

PURPOSE: To compare the surgical outcome of limbus-based group with that of fornix-based group undergone trabeculectomy with mitomycin C (MMC). METHODS: 46 eyes of 42 patients with trabeculectomy with MMC who were observed for 6 months or more were included. A limbus-based conjunctival flap was used for 23 eyes of 21 patients, and a fornix-based conjunctival flap for the other 23 eyes of 21 patients. And the intraocular pressure (IOP), visual acuity and postoperative complications were checked. RESULTS: In the IOP control, there were no differences between two groups after surgery except 18 months. The IOP of the limbus-based group at 18 months was lower than that of fornix-based group (10.7 +/- 9.5: 14.8 +/- 11.2 mmHg, p=0.030). In the postoperative complications, the number of persistent hypotony in limbus-based group was more than that of fornix-based group (6: 1 eyes, p=0.048). There were no differences between two groups in the success rates without additional medication, but the success rates of fornix-based group with additional medication at 12 months were higher than those of limbus-based group (44.4: 77.3%, p=0.033). Also the cumulative success rates of fornix-based group with medication were higher than those of limbus-based group (p=0.040). CONCLUSIONS: Fornix-based conjunctival flap which has shown lower persistent hypotony and higher success rates than that of limbus-based conjunctival flap is recommendable for trabeculectomy with MMC.

Clinical Analysis of Glaucoma Patients Undergone Filtration Surgery

PURPOSE: We evaluated clinical aspects of the glaucoma patients who had undergone trabeculectomy. METHODS: We analyzed 211 patients' medical records who had undergone trabeculectomy in Chungbuk National University Hospital from August 1991 to December 1999 retrospectively. RESULTS: The mean age of the patients was 57.1+/-16.3 years and the 119 eyes (56.4%) had bilateral glaucoma. Among them, 57 eyes (47.9%) had primary open-angle glaucoma. Cataract was the most common cause of decreased vision in the fellow eye during the mean follow-up period of 25.4+/-22.3 months. The number of patients whose visual acuity in the fellow eyes less or equal to hand movement before surgery were 25 eyes (11.8%) and they resulted from glaucoma (18 eyes) and trauma (4 eyes). CONCLUSIONS: The fellow eyes of the glaucoma patients who had undergone trabeculectomy were easily subject to high prevalence of glaucoma that may lead to blindness. Therefore, more thorough and periodic ocular examination and appropriate treatments are mandatory to prevent further progress in these eyes with more advanced glaucoma.

Midd-term effects of trabeculectomy with mitomycin C in neovascular glaucoma patients

Twenty four eyes from 23 neovascular glaucoma (NVG) patients, who underwent trabeculectomy with 0.2 or 0.4 mg/ml MMC in least the previous 6 months, were examined in order to evaluate the mid-term effects of a trabeculectomy with mitomycin C (MMC) in NVG. Success defined when an intraocular pressure (IOP) 5 mmHg with or without medication was observed. The mean IOP was reduced from 46.8+/-12.9 mmHg preoperatively to 18.2+/-12.0 mmHg at the last follow-up (mean = 25.8 months). The overall success rates at 1-, 3-, 6-, 9-, and 12-months after surgery were 71%, 58%, 50%, 29%, 29% respectively. The number of anti-glaucoma medications administered was significantly reduced from 2.6+/-0.7 preoperatively to 0.9+/-1.0 postoperatively (Wilcoxon signed rank test, p = 0.005). In addition both the intraoperative MMC concentration and application time had no influence on lowering the IOP (logistic regression analysis, p = 0.228, 0.910, respectively). There was a similar incidence of postoperative complications in both the success and failure group. These results suggest that a trabeculectomy with MMC is an effective surgical procedure in NVG patients and the MMC concentration is not crucial for reducing the IOP postoperatively.

The Change of Corneal Astigmatism after Extracapsular CataractExtraction with 7 mmScleral Tunnel Incision

In recent days, cataract surgery has trend to reduce postoperative astig-matism and acquired early visual rehabilitation.Phacoemulsification with small incision and insertion of foldable intraocular lens has been used popularly, but its high cost and intraoperative or postoperative complication especially in old age with dense nucleosclerosis could be detrimental to patients. Postoperative corneal astigmatic changes and visual rehabilitation were evaluated after extracapsular cataract extraction with 7 mmscleral tunnel incision (Group I, 7 mm-ECCE, 28 eyes)by comparing with those after phacoemulsification with 3.5 mmscleral tunnel incision (Group II, 3.5 mm-Phaco, 41eyes).One piece PMMA intraocular lens was inserted in group I, while foldable intraocular lens in group II.Surgically induced corneal astigmatism was calculated by Cravy's vector analysis.There was no statistically signifi-cant difference between group I and group IIfor surgically induced corneal astigmatism (Kt)after postoperative one month (p>0.05).In group I and group II, corneal astigmatism was with-the-rule in early postoperative days, and changed to against-the-rule in postoperative 3 months.There was no statistically significant difference between group I and group IIincorneal astigmatism during all follow-up period (p>0.05). Therefore, 7 mm-ECCE could be an effective method for old patient with high grade nucleosclerosis or when phacoemulsification was unavailable.

Comparative Study of Combined Cataract Surgery in Primary Angle-Closure Glaucoma

Trabeculectomy, as an operation precedure for glaucoman, decrease intraocular pressure(IOP)effectively. But the amount of decrease in IOP is different according to the etiology of glaucoma. Thirty four primary angle-closure glaucoma patients (37 eyes)who had undergone trabeculectomy only or trabeculecomy combined with cataract surgery and had been subsequently followed up for least 6 months, were enrolled in this study. In 12 patients(14 eyes) among 16 patients (18 eyes, Group 1) who had undergone trabeculecto-my only, IOP was controlled without glaucoma medication, while glaucoma medication was needed in the other 4 patients (4 eyes). Among 18 patients (19 eyes, Group 2) who had undergone trabeculectomy combined with cataract surgery, IOP were controlled without glaucoma medication 9 patients (10 eyes); controlled with medication in 8 patients (8 eyes); and not controlled even with 1 patient (1 eye). The amount of decrease in IOP was no statistically different between the two groups. Group 2 had deeper anterior chamber than Group 1 (p<0.01). The above results suggest that the combined pro-cedure may benefit in primary angle-closure glaucoma patients, especially old complicated patients.

Corneal Bleb Following Bleb Excision and Advancement of a Fornical Conjunctival Flap

Advancement of a fornical conjunctival flap is the method used for bleb reconstruction after excision of necrotic leaking bleb. The authors have experienced a case of corneal bleb at 4 months after necrotic leaking bleb excision and advancement of fornical conjunctiva. The patient complained of irritation. The authors sutured conjunctival bleb over the cornea tightly to the limbus with full corneal thickness. Postoperatively corneal bleb and irritation symtom disappeared and visual acuity improved, but at postoperative 1 month, small corneal bleb recurred, which was punctured with 26G needle and Nd: YAG laser. Subsequently it disappeared and did not recur.

Midterm follow-up of necrotic bleb excision and advancement of the fornical conjunctiva

Mitomycin C has improved the success rate of glaucoma filtering surgery in patients at high risk for surgical failure. However chronic hypotony is marked by decreased vision and a late-onset leaking bleb after filtration surgery using mitomycin C. Bleb excision and conjunctival advancement is the method of choice to repair bleb leakage and chronic hypotony. Five eyes from five patients were received glaucoma filtration surgery with topical mitomycin C. All of the patients' blebs were avascular and transparent. The reasons for bleb excision were two spontaneous bleb leaks, two traumatic bleb leaks and one case of severe irritation. The mean follow-up period was 18.4 +/- 8.3 months (ten to 29 months). Cataract surgery was combined in one eye. Postoperative intraocular pressure (IOP) increased from 2.3 +/- 1.5 mmHg to 9.5 +/- 3.7 mmHg at nine months postoperatively in four eyes. It went from 28 mmHg to 40 mmHg in one patient with uveitis, for whom a second trabeculectomy with mitomycin C; 0.4 mg/ml for 3 minutes, was performed. After surgery, IOP decreased to 4 mmHg in three months. Postoperative visual acuity improved four snellen lines in three eyes. A partially avascular bleb recurred in three eyes, a corneal bleb in one eye and blepharoptosis, which disappeared spontaneously at four months postoperatively, in one eye. Necrotic bleb excision and advancement of fornical conjunctiva were useful methods to increase IOP and to improve visual acuity for the patient experiencing irritation symptoms, and for leaking blebs, and hypotonic maculopathy.

Effectiveness of Argon Laser Peripheral Iridoplasty in the Treatment of Severe Acute Angle-Closure Glaucoma

We used argon laser peripheral iridoplasty to reduce intraocular pressure[IOP] in acute angle-closure glaucoma[ACG] which is unrelieved by medical and physical treatments and could not be treated by peripheral iridotomy due to edematous cornea and turbid aqueous. Eight of 16 eyes [16 patients] were successfully treated. These successfully treated eyes had a mean duration of angle closure of 4.1 days and 8 unsuccessfully treated eyes 9.2 days. The 6 eyes of 8 eyes with successful reduction of IOP after argon laser peripheral iridoplasty were treated peripheral iridotomy at average 1.7 day later and had deep anterior chamber. After a mean follow-up period of 2 months, 7 of these 8 successfully treated eyes had an IOP less than or equal to 21mmHg. Argon laser pripheral iridoplasty may be successful in treating ACG which is unrelieved by medical and physical treatments and could not be treated by pripheral iridotomy, especially in cases that are recognized and treated soon after onset.

The Effect of Mitomycin C Trabeculectomy in Neovascular Glaucoma

The authors studied retrospectively the results of mitomycin C (MMC) trabeculectomy in 19 eyes with neovascular glaucoma which could be followed up more than 4 months after surgery. Twelve eyes(63%) were classified as success group and 7 eyes(37%) were classified as failure group. In the success group, the mean intraocular pressure(IOP) was significantly reduced from 52.1+/-10.1mmHg preoperatively to 10.1+/-3.8mmHg at last follow Kaplan-Meier survival analysis, cumulative success rates at 6 and 12 months intervals were 68%, 59% respectively. In the failure group, the mean IOP was reduced significantly from 51.9+/-8.1mmHg preoperatively to 26.6+/-13.4mmHg at last follow up. The mean number of medications to reduce IOP was also reduced from 2.6+/-0.5 preoperatively to 1.3+/-0.8 at last follow up. The causes for failure were inadequate IOP control in 5 eyes(26%), loss of light perception in 1 eye(5%), and reoperation to reduce IOP(5%). Complication included hypotony in 4 eyes(21%), late bleb leakage in 2 eyes(10.5%), spontaneous hyphema in 2 eyes(10.5%), cataract progression needing extraction in 2 eyes(10.5%). We think that MMC trabeculectomy may be the first choice procedure before doing cyclocyro-therapry or cyclodestructive procedure using laser.

Effects of postoperative mitomycin C eyedrop on trabeculectomy in refractory glaucoma patients

To investigate the effects of postoperative mitomycin C (MMC) eyedrop as an adjunct to intraoperative MMC in refractory glaucomas, 15 eyes of 14 glaucoma patients (age; 47.0 +/- 15.5 years) in need of trabeculectomy were studied. Preoperative diagnoses were secondary glaucoma to uveitis in seven patients, neovascular glaucoma in four, pseudophakic glaucoma in three, and aphakic glaucoma in one. Six patients who had neovascular glaucoma or history of a failed trabeculectomy with intraoperative 0.2 mg/ml MMC received intraoperative 0.4 mg/ml MMC. The others received 0.2 mg/ml MMC for 3 minutes. During the follow-up period, postoperative MMC eyedrop was applied, depending on the condition of the filtration bleb. The eyedrop was 0.2 or 0.4 mg/ml, applied four times a day for one week. The follow-up period was 18.1 +/- 7.4 months. The success rates were 93.3%, 86.7%, and 78.0% at postoperative 1, 4, and 18 months, respectively. There was neither early hypotony nor wound leak. Corneal epithelial defects (26.7%), corneal ulcers (6.7%), and cataracts (6.7%) were, however, observed. Postoperative MMC eyedrop application was a convenient and effective adjunct to intraoperative MMC in refractory glaucomas.

Effect of Long Term use of Topical Antiglaucoma Medications on Aqueous Humor in Rabbits

Various studies have been performed to identify change in the constituents of aqueous humor which was suggested either as a factor for fibroblast proliferation causing glaucoma filtering bleb failure or as a factor for the pathogenesis of primary open angle glaucoma. This study was designed to investigate change of aqueous humor composition after long-term topical antiglaucoma medication. After 16-week instillation of pilocarpine 4% and Betagan(TM) in ten rabbits, aqueous humor was obtained from eight control and eight experimental eyes. Protein bands were identified by SDS-PAGE and gold staining techniques. The density and distribution of these protein bands was significantly different between the two groups. The result of this study may give help for future study of pathogenesis of primary open angle glaucoma and causes of high failure rate after glaucoma filtration surgery in patients on chronic topical antiglaucoma medication.

Induction of vitreolysis and vitreous detachment with hyaluronidase and perfluoropropane gas

To simulate the posterior vitreous detachment (PVD) in the rabbit, 1 IU hyaluronidase and/or 0.2 ml of perfluoropropane gas was intravitreally injected. Ophthalmoscopic, light microscopic examination prepared by cryotechnique, electron microscopic examination, and electroretinogram were done on the 3rd and 28th postoperative days. As a result, the eyes undergone simultaneous intravitreal injection of 1 IU hyaluronidase and 0.2 ml perfluoropropane gas showed membranous structure split from the internal limiting membrane of the superior retina in 3 days after injection. The eyes also demonstrated membranous structure separated from the superior retina after 28 days, simulating vitreous detachment. On the contrary, neither agent alone induced vitreous detachment. No toxic retinal changes associated with simultaneous intravitreal injection of 1 IU hyaluronidase and 0.2 ml perfluoropropane gas were observed. Therefore, with a future support by histologic examination other than cryotechnique and by immunohistochemical analysis, the simultaneous intravitreal injection of perfluoropropane gas and hyaluronidase would be a promising method to induce vitreous detachment in non-vitrectomized eye.

Effects of topical mitomycin C on glaucoma filtration surgery

We studied the efficacy and safety of using topical mitomycin C (MMC) as an adjunct to glaucoma filtration surgery. Trabeculectomy was performed in 23 eyes of 19 patients with poor surgical prognosis. After the preparation of a scleral flap, 0.2 mg or 0.4 mg/ml MMC was applied to the exposed tissue for 5 minutes. The wound was then irrigated with 250ml of normal saline. The mean follow-up period was 7.8 months. Preoperative mean intraocular pressure (IOP) was 33.8mmHg, and the mean IOPs on 1, 3, 6, and 12 months after operation were 10.3, 12.5, 12.4 and 12.3mmHg, respectively. At postoperative 12 months, 74.7% achieved an IOP of less than or equal to 20mmHg without any antiglaucoma medication. There were early postoperative complications of aqueous leaking from conjunctival wounds in 3 eyes (13.0%), shallow anterior chamber in 2 eyes, and hyphema in one eye and one eye had long-term hypotony lasting more than 3 months. Although MMC is simple to use, it is a potent adjunct to glaucoma filtration surgery, more work should follow to determine the mechanism of action, indications, dosage and optimal exposure time of MMC.

Effects of sodium hyaluronate on filtration bleb in rabbits

Sodium hyaluronate can be used during a trabeculectomy to prevent early postoperative hypotony and shallow anterior chamber. To determine its long-term effect on the outcome of filtration surgery, fifteen rabbits underwent a osterior-lip sclerectomy in both eyes. Into their right eyes 0.2ml sodium hyaluronate, and into left eyes 0.2ml balanced salt solution were injected intracamerally. Gross and histopathological differences of bleb were observed. There was no statistically significant difference in longevity of the filtration bleb.

Effects of Topical Mitomycin C on Glaucoma Filtration Surgery

We studied the efficacy and safety of using topical mitomycin C(MMC) as an adjunct to glaucoma filtration surgery. Trabeculectomy was performed in 23 eyes of 19 patients with poor surgical prognosis. After the preparation of a scleral flap. 0.2mg or 0.4 mg/ml MMC was applied to the exposed tissue for 5 minutes. The wound was then irrigated with 250ml of normal saline. The follow-up period was from 2 to 12 months(mean 7.8 +/- 4.3 months). Preoperative mean intraocular pressure(IOP) was 33.8 +/- 7.1 mmHg, ranged from 25 to 51 mmHg. The mean IOPs after 1, 3, 6 and 12 months were 10.3 +/- 4.4, 12.5 +/- 6.9, 12.4 +/- 6.6 and 12.3 +/- 6.7 mmHg, respectively. Nineteen(82.6%) among 23 eyes were successfully controlled with the IOP below 20 mmHg without any antiglaucomatous therapies, and success rate was 0.747 by Kaplan-Meier method at Postoperative 12 months. There were early postoperative complications of aqueous leaking from conjunctival wound in 3 eyes(13.0%), shallow anterior chamber in 2 eyes, and hyphema in one eye and one eye had long-term hypotony lasting more than 3 months. Although MMC is simple to use and a potent adjunct to glaucoma filtration surgery, more work will be needed to determine the mechanism of action, indications, dosage and optimal exposure time of MMC.

Effects of aqueous humor on filtering bleb in rabbits

Preoperative aqueous humor, known to inhibit the growth of fibroblasts in tissue culture assay, was used as an adjunct to filtering surgery in rabbits to determine its effect in vivo on the outcome of filtering surgery. Fifteen rabbits underwent a posterior-lip sclerectomy in both eyes. In experimental eyes 1.4 ml preoperative aqueous humor and in fellow eyes 1.4 ml balanced salt solution were injected intracamerally. Gross and histopathological differences of bleb were observed. In this animal experiment, although there was no statistical significance or late postoperative effect, the rabbit eyes refilled with preoperative aqueous humor intracamerally just after filtering surgery, had a larger bleb and less fibroconnective tissue on the bleb than the control eyes in the early postoperative period.

Ocular dimensions with aging in normal eyes

To quantify the dynamic changes taking place in the anterior segment, we measured the anterior chamber depth (ACD), lens thickness (LT) and their difference between sexes and age groups in normal eyes using contact ultrasonography and anterior chamber photography. There were 141 women (241 eyes) and 76 men (130 eyes) between the ages of 10 and 70 years. In normal eyes, the lens thickness was increased and the anterior chamber depth was decreased with aging in both sexes. The anterior chamber depth showed an accelerated decrease between the 4th and 5th decades in females and the ratio of anterior chamber depth to axial length was smaller in females than in males after the 5th decade. The results suggested that the prevalence of angle closure glaucoma will be increased in females after middle age.