BINA
Year:2002 | Volume:8 | Issue:1|Papers Count:17

Purpose: To evaluate the risk factors of corneal graft rejection and failure in cases of penetrating keratoplasty (PK) performed during the years 1998-1999.Materials and Method: As a cross sectional study, demographic and individual characteristics, causes of PK, rejection types, and risk factors were evaluated. Risk factors of graft rejection, survival, duration of clarity, and finally failure rates for each factor were studied. Data was analyzed with SPSS 10.0; Chi- square and multivariate regression tests were used for statistical analysis.Result: During two years of study, 295 PKs were performed on 286 patients including 67% men. Average age was 37 ± 20 years. Patients were followed for 20 ± 10 months. Graft rejection occurred in 31.8% of cases within 7.3 ± 6 month. Endothelial rejection was the most common type of rejection (20.7%). Risk factors for rejection were: extensive corneal vascularization, regraft, iridocorneal adhesions, irritating suture, active intraocular inflammation at the time of operation, secondary anterior segment surgery, history of trauma, poorly controlled intraocular pressure (IOP) and glaucoma, previous graft rejection, reactivation of herpes on the graft, and eccentric PK (P<0.05). On the other hand, patients' age at the time of PK, donor cornea size, and bilateral PK were not found to be a significant risk factor for graft rejection (P>0.05).Conclusion: Severity and extent of recipient corneal vascualrization, iridocorneal adhesions, irritating sutures, active inflammation, regraft, trauma, poorly controlled IOP, recurrence of herpetic keratitis, eccentric graft, and graft ulcer were related to graft rejection. Recognition of these risk factors and early diagnosis and proper treatment of graft rejection can extend graft survival and clarity.

Purpose: To compare the visual outcomes and complications of penetrating keratoplasty (PK) and deep lamellar keratoplasty (DLK) in cases of advanced and severe keratoconus (KCN).Materials and methods: This retrospective comparative study was performed on 48 eyes of 45 patients with advanced and severe KCN that underwent PK or DLK. Main outcome measures were visual acuity, astigmatism, graft survival, and complications. Result: We performed PK in 35 eyes of 32 patients and DLK in 13 eyes of 13 patients. Mean follow-up in PK and DLK groups was 31 ±17.6 months and 25± 16 months, respectively (P> 0.05). Mean pre-operative and last visit (at least 3 months after suture removal) BCVA was 1.05 and 0.118 LogMAR in the PK group and 1.160 and 0.169 LogMAR in DLK group. There was no statistically significant difference in mean UCVA, BCVA, donor diameters, recipient bed diameters, postoperative corneal power, and astigmatism, between PK and DLK groups. There was one endothelial rejection in the PK group. All corneas were clear at the last visit.Conclusion: Visual outcomes are similar in PK and DLK. DLK is a safe and effective procedure, because it is an extraocular procedure and has less rejection complications and follow up is easier and shorter. We propose DLK for advanced and severe KCN without central corneal scarring.

Purpose: To compare the in vitro sensitivity of bacterial isolates of corneal ulcers to five types of antibiotics.Material and methods: This prospective study was performed on 100 cases of corneal ulcer who were referred to Khalili Hospital emergency service. After diagnosis of possible infective keratitis, direct smear and culture were prepared from the active area of the ulcer and incubated at the proper temperature. In culture positive cases, typing of bacterial species and antibiotic sensitivity tests to ciprofloxacin, ofloxacin, amikacin, gentamicin and cefazolin were performed. Culture negative plates were incubated at 37 C and 25 C to observe the growth of fungi. Identification data, history of topical antibiotic use, interval between onset and referral, predisposing factors, and clinical characteristics of the ulcer were recorded for every patient. The result was interpreted with Fisher and Chi square tests.Results: The study consisted of 57% male and 43% female patients. Culture was positive in 56% of the cases (40% bacteria and 16% fungi). The interval between onset and referral was 1-30 days (mean 10.4 days). Eighty-three percent of the patients had used topical antibiotics before referral. The isolated bacteria were sensitive to: ofloxacin in 95%, ciprofloxacin in 92.5%, amikacin in 92.5%, gentamicin in 65%, and cefazolin in 62.5% of the cases. Bacterial isolates were coagulase negative staphylococci in 45% and pseudomonas in 25% of the cases. Forty percent of pseudomona species isolutes were resistant to both cefazolin and gentamicin, hoewer they were susceptible to the other three antibiotics. If sensitivity to either gentamicin or cefazolin alone is supposed to be enough for sensitivity to a combination of them, there was no statistically significant difference between the sensitivity of the bacterial isolates to this combination and each of the other three antibiotics, although this value was statistically significant for the pseudomonas species.Conclusion: Ciprofloxacin, ofloxacin, and amikacin are effective against most of the bacterial pathogens of corneal ulcer at our center. Gentamicin or cefazolin alone are not recommended as empirical treatment for bacterial keratitis, but their combination is effective for the most of the bacterial pathogens of corneal ulcer except pseudomonas species.

Purpose: To evaluate the power of two methods of potential acuity pinhole (PAP) and illuminated near card (INC) in prediction of final visual acuity after cataract surgery.Materials and Methods: This sequential double blind cross-over clinical trial was performed on 100 eyes of 100 patients. The patients were classified into 3 groups in terms of best corrected visual acuity (BCVA): I-BCVA ≥ 20/50, II-BCVA of 20/60-20/200, and III-BCVA of less than 20/200 to a minimum of 20/400. Potential visual acuity with the two methods (PAP and INC) was predicted before surgery. Eight weeks after cataract surgery, far BCVA was evaluated and the two methods were compared.Results: Mean age of the patients was 65 years (range 30-90). Prediction power of PAP test in groups I, II, and III was 75%, 91.7%, and 73.6%, respectively. Prediction power of INC test in groups I, II, and III was 75%, 87.5%, and 80.6%, respectively. Linear relationship between PAP and post operative far BCVA (R) was 0.71 and far INC was 0.51 (regression analysis, P<0.0001). Linear relationship of PAP method and post operative far BCVA in INC method were: Far Log n = -0.12+0.52 PAP Log n and Far Log n = -0.267+0.44 INC Log n, respectively.Conclusion: Prediction powers for visual acuity in PAP test and INC test were nearly equal. Not considering the preoperative BCVA, both methods had the required power for prediction of visual acuity.

Purpose: To identify clinical characteristics associated with outcome of treatment in PFV based on a modified classification.Methods: In this noncomparative case series, 54 eyes of 47 consecutive patients with PFV managed from 1981 to 1998 at a tertiary eye hospital were reviewed. Pars plicata lensectomy and vitrectomy was performed in 34 eyes and translimbal lensectomy and vitrectomy in 5 eyes. Fifteen eyes were managed non-surgically. Measured outcomes were visual improvement and cosmetic acceptability. Visual improvement was defined as at least one Zipf's category improvement of best corrected final vision as compared with initial visual acuity, provided that final vision of CSUM (central, steady, unmaintained equal to 20/100-20/30) was obtained. Cosmetic acceptability was defined as absence of small orbit, externally small appearing eye with microcornea and hypotony, eye deviation more than 35 prism diopters without strabismus surgery, and corneal opacity.Results: Excluding six inoperable eyes, in 10 out of 33 operated eyes (30.3%) improvement of vision was obtained including 4 eyes with anterior PFV and 6 eyes with combined PFV. In the univariate analysis, factors such as anterior form of PFV, performing surgery in combined form and having a normal retina, had weak association with a higher chance of visual improvement. In multivariate regression analysis the chance of developing an unacceptable cosmetic appearance was higher in females than males (OR=10.5), and also in bilateral cases (OR=7.9). Offspring of consanguineous marriages had a more severe form of PFV.Conclusion: Although visual potential is limited in PFV, some eyes with anterior or combined form and normal retina achieved improvement of visual acuity after surgery. However, statistically no single factor except gender and bilateral PFV (for cosmetic unacceptability) could effectively predict results of treatment. Therapy should be individualized based on clinical findings. Genetic studies in offsprings of consanguineous marriages with PFV may prove informative.

Purpose: To determine the results of transscleral fixation of intraocular lens (IOL) combined with complete vitrectomy and placement of an encircling band.Material and methods: The records of 18 patients who underwent transscleral fixation of IOL combined with complete vitrectomy and prophylactic band were reviewed. The operations were performed consecutively from 1993 to 2000.Results: Age of the patients ranged from 5 to 76 years (mean 34.8 years). Average follow up was 6 months. Seven eyes were aphakic, 4 had subluxated cataractous lenses, 6 had dislocation of IOL into the vitreous cavity, and one had a subluxated IOL. Capsular support was absent in all 18 cases. Previous traumatic or surgical iris and angle damage and or peripheral anterior synechiae were noticed in almost all cases. After surgery, 9 eyes (50%) gained visual acuity of 20/40 or better. Early postoperative fibrin reaction occurred in 3 young patients. Cystoid macular edema which was present in cases with history of complicated cataract surgery resolved postoperatively. Late complications included: 1) subluxation of the transsclerally fixated IOL which occurred after 2.5 years in a 5-year-old patient and after 8 years in a 44-year-old patient, 2) retinal detachment complicated by proliferative vitreoretinopathy which occurred in a 55-year-old patient 7 months after the surgery.Conclusion: In the absence of capsular support, transscleral fixation of a posterior chamber intraocular lens may be combined with vitreoretinal surgery in selected patients. This procedure is efficient for visual rehabilitation. As the long term results are not known yet, application of this technique in children deserves caution.

Purpose: To determine the success rate of scleral buckling procedure without cryopexy with intraoperative or postoperative laser photocoagulation in patients with primary retinal detachment.Patients and methods: In an interventional case series study, 73 patients with primary retinal detachment underwent scleral buckling surgery with argon laser application around the breaks and on the buckle which was delivered by indirect ophthalmoscope intraoperatively in 34% of the cases, or by slitlamp and contact lens technique postoperatively in 66% of the cases.Results: Fifty four patients were male (74%) and 19 were female (26%), with mean age of 59.1 years (range 21-79 year). Forty seven was phakic (64%), 14 were pseudophakic (19%), and 12 were aphakic (17%). PVR range was from B to C2 (B: 88%, C1: 8%, C2: 4%). Anatomic success rate was 100% intraoperatively, however and within 3 to 8 weeks redetachment occurred in 12.5% of cases; reattachment was accomplished in 7% of cases by SF6 injection and laser reapplication (final success rate 94.5%). The remaining 5.5% cases, led to pars plana vitrectomy, membrane peeling, endolaser application, and silicone oil injection. All cases of reoperation had reattached retina up to the end of the study. Mean follow up time was 58 months.Conclusion: Considering the proven adverse effects of cryopexy and its role in PVR formation which is the major cause of failure in scleral buckling surgery, laser photocoagulation can be a good substitute to create chorioretinal scar and obtain acceptable results.

Purpose: To compare the long term results of three different procedures for correction of involutional entropion (tarsal strip, three fornix sutures, tarsal strip + three fornix sutures) among patients referred to Labbafinejad Medical Center during 1991-2001.Method: Study was performed on the hospital records of all patients with lower lid entropion who underwent surgery. Patients with less than three months of follow-up and previous operation on the same eyelid were excluded from the study. Age, gender, visual acuity, method of operation, results of operation, improvement of symptoms, and post surgical complications were reviewed.Results: During this period, 67 lids in 51 patients underwent surgery including lateral tarsal strip (LTS) in 26 lids (38.8%), three fornix sutures in 11 lids (16.4%), and the combined procedure in 30 lids (44.8%). Patients were followed for a minimum of three months and average of 6.5 months. Symptoms were epiphora, foreign body sensation, abnormal lid position, decreased vision, and burning sensation. Lid position correction rate was 88.5% for LTS, 90.9% for three sutures, and 96.7% for the combined method. Total cure (lid position and symptoms) was achieved in 76.9% of LTS cases, 72.7% of three sutures cases, and 86.6% of the combined procedures. Two cases of complications were seen, including granulation tissue formation in the lateral canthus and stitch abscess.Conclusion: The combined procedure seems to have better results in terms of symptomatic improvement and lid position than the two other procedures.

Purpose: To review the current methods in the diagnosis and management of patients suffering from different forms of endophthalmitis.Method: By literature search up to 2001, a relevant list of articles was retrieved. All articles were reviewed, summarized and used for preparation of this manuscript Results and Conclusion: Except the Endophthalmitis Vitrectomy Study (EVS) which is a randomized clinical trial, the published literature contains information from case series, which lack a control group and randomization. Follow up is limited and visual outcome varies widely and is highly dependent on the type of endophthalmitis and emergent referral of patients for proper management of intraocular infection. Considering the poor visual outcome of all forms of endophthalmitis, prophylaxis should have a greater role. Prognosis of these unfortunate events depends on immediate diagnosis, differentiation of acute from chronic form, and early establishment of proper medical and surgical treatment. Sampling intraocular fluids for microbiological study usually provides reliable results. Prognosis in culture negative cases, late onset endophthalmitis, and infection with low virulence organisms is better than infection with streptococci, gram negative organisms, and bacillus cereus.

Purpose: To report a case of corneal ring infiltration following topical tetracaine abuse, which is the most severe from of toxic ulcerative keratitis.Patient and findings: A 19-year-old man complaining of severe pain in his left eye, was referred to Farabi Eye Hospital. There was a history of tetracaine abuse for a week. Clinically, the patient had conjunctival injection and a corneal ring infiltration which subsided after cessation of tetracaine.Conclusion: The clinical presentation of corneal ring infiltration following tetracaine abuse can mimic acanthamoeba, herpetic, and bacterial keratitis. Appropriate management depends on high level of suspicion and obtaining a precise history of anesthetic drug abuse.

Propose: To report a case of lost medial rectus muscle with successful surgical management through fixation of the globe to the medial orbital rim with a 240 silicone band.Patients and findings: The patient is a 14 year-old girl with history of operation on the right eye for correction of exotropia with subsequent severe limitation of adduction and increase in exotropia. She underwent surgical exploration last year and the clinical diagnosis of lost medial rectus muscle was confirmed. Maximal lateral rectus recession and half-tendon vertical rectus muscle transposition was done but the result was not cosmetically acceptable. Finally the globe was fixated to the medial orbital rim with a 240 silicone band.Conclusion: Fixation of the globe to the orbital rim with a silicone band is a new alternative procedure for managing lost medial rectus muscle, which needs further investigation.

Purpose: To report a case of bilateral choroidal metastases from a breast carcinoma treated with transpupillary thermotherapy (TTT).Patient and findings: A 44 year-old- woman was referred with sudden loss of vision in her right eye for 5 days. Visual acuity was decreased to 20/160 in the right eye, and was 20/20 in the left eye. Fundus examination disclosed a large-sized tumor (6×7 disc diameter) in the posterior pole with subretinal fluid in her right eye, and a small size tumor (1.5×1.5 disc diameter) temporal to macula of her left eye. Right side mastectomy due to breast cancer had been performed one year prior to the recent referral. The choroidal mass in both eyes were treated with thermotherapy with a relatively good response.Conclusions: Choroidal metastases of breast carcinoma are common after removal of the primary tumor. TTT may be a useful treatment in such cases.