BINA
Year:2005 | Volume:10 | Issue:5 (41)|Papers Count:20

Purpose: To determine the clinical and paraclinical features of multiple sclerosis (MS) in patients presenting for the first time with optic neuritis.Methods: In this descriptive study, 35 patients with clinical evidence of optic neuritis were enrolled. Our evaluation included a neurological examination, visual evoked potentials (VEP), brainstem-auditory evoked potentials (BAEP), and brain MRI. Results: Mean patients' age was 27.49±8.43 years (range 14-51) including 30 female (85.8%) and 5 male (14.2%) subjects. Of 35 cases, 19 (54%) had other clinical signs of MS on neurological examination including loss of abdominal reflexes and presence of Babinski sign, 27 (77%) had abnormal brain MRI, 12 (34%) had abnormal VEP in the unaffected fellow eyes, and 4 (1 1%) had abnormal BAEP.Conclusion: The frequency of optic neuritis as the first manifestation of MS in our study was more than twice that in other countries. So it is recommended that all optic neuritis patients be referred to a neurologist for evaluation for MS.

Purpose: Comparison of the results of visual evoked potential (VEP) in time domain and frequency domain between multiple sclerosis (MS) suspected patients and normal indivisuals. Method: Eleven MS suspected patients with normal visual findings and 20 normal individuals were tested by VEP. Results were compared between two groups. Results: The time domain results showed no significant difference between the two groups. Results of the frequency domain showed that Fmod value in the MS group (4.1±1.4 Hz) was less than the value in normal subjects (7.9±2.8 Hz) but, the number of peaks in power spectrum in the MS group (3.8±0.9) was more than the value in normal subjects (1.5±0.3). (P<0.001) Conclusion: Decreased nerve conduction velocity, nerve impulse blockage, and refractory period increase in MS may cause low pass shift in frequency spectrum that may lead to Fmod decrease and increase the number of peaks in spectrum. These finding may be useful for early diagnosis of MS.

Purpose: To evaluate the underlying causes of rhegmatogenous retinal detachment (RRD) in eyes operated for this reason.Methods: Out of 1473 patients who underwent retinal detachment surgery, records of 369 patients were randomly selected and evaluated for the types of retinal breaks, the underlying disorders, and location of breaks.Results: Fifty-two percents of patients were less than 50 years old and 63.4% of them were male. Twenty-two percents of the eyes were aphakic or pseudophakic and 18% were myopic. Trauma was the cause of detachment in 10% of the eyes. More than one break was found in 70% of the eyes, 80% of which were less than 90 degree apart. Thirty percents of the eyes had only one break, 40% I of which were in superotemporal and 30% in inferotemporal quadrant. Macular hole was found in 3.5%, dialysis in 6%, peripheral hole in 3.5%, and retinal tear in 81% of the eyes. In addition, PVR grade C or more was seen in 7.6% of the eyes. Conclusion: The causes, underlying disorders, and location of breaks is comparable with studies from other parts of the world. Evaluation of these parameters in other Iranian ophthalmic centers is suggested.

Purpose: To determine the frequency of risk factors for retinal vein occlusion (RVO) in patients referred to a private clinic in Rasht during 1995-2001.Methods: This cross-sectional study was conducted on all patients with RVO who were referred to the clinic. Sex, age, hypertension (HTN), cardiovascular diseases (CVD), diabetes mellitus (DM), hypercoagulable states, glaucoma, smoking, hyperlipidemia (HLP), and refractive errors were evaluated.Results: This study included 143 cases of branch retinal vein occlusion (BRVO) and 119 cases of central retinal vein occlusion (CRVO). In BRVO group, mean age was 60.5:t17.5 years. Prevalence of HTN, HLP, CVD, smoking, DM, and glaucoma was  62.2%, 52.1%, 44.5%, 43.7%, 31.9%, and 8.4%, respectively. In CRVO group, mean age was 58.8%:t2.3 years. The prevalence of the abovementioned risk factors in this group was 70.6%, 58.0%, 51.7%, 36.4%, 20.3%, and 2.1%, respectively. None of the patients had hypercoagulablity. Most patients had±1 diopter of refractive error (67.7% in the BRVO group and 82.3% in the CRVO group). Conclusion: The prevalence of HTN, HLP, CVD, smoking, DM, and glaucoma are significantly high in RVO patients. Early diagnosis and management of these risk factors may decrease the prevalence of RVO diseases.

Purpose: To introduce the technique and results of vitrectomy surgery with removal of cyclitic membrane by placement of radial cuts over the membrane in traumatized eyes. Methods: Vitrectomy in 8 eyes of 8 patients after penetrating ocular trauma revealed that fibrovascular tissue was present over the pars plicata. To remove the membrane, radial cuts were placed over the membrane first and then the pieces were removed by vitrectom. Pre- and postoperative visual acuity (VA), applanation tonometry results, and ophthalmic examination results were retrieved from hospital records of the patients. Results: The patients included 5 males and 3 females. Age range was 2-22 years (median; 11.5 years). All eyes had sustained penetrating globe injury involving the sclera 11 to 90 days median; 23 days) betore the operation. Two eyes had undergone vitrectomy once before. Preoperative VA was light perception or hand motion in 7 eyes and 7 eyes were hypotonic before the operation. Extent of the cyclitic membrane was from 150 to 360 degrees (median; 200 degrees). Patients  were followed for 6-18 months (median; 12 month). At the last visit, VA was 20/60 or more in 6 eyes and lOP was normal in 7 eyes (8-20 mmHg, median; 11 mmHg). One eye was lost due to proliferative vitreoretinopathy. There were no other major retinal complications. Conclusion: Treatment of cyclitic membranes has always been difficult. The described technique of surgery had very good results in our patients.

Purpose: To determine factors that affect and predict final visual acuity, retinal attachment, and ocular survival after open-globe injuries.Methods: One-hundred sixteen eyes with open globe injuries were evaluated longitudinally from September 2001to February 2004. Age, sex, involved eye, best corrected visual acuity (BCYA), afferent papillary defect (APD), size and location of laceration, cataract, iris prolapsed, vitreous prolapsed, retinal detachment (RD), intraocular forgien body (IOFB), deep vitrectomy, and type of injury were evaluated as predisposing factors by logistic regression analysis for final visual acuity and retinal attachment and by Chi Square for survival rate. Results: Enucleation was performed in 16 eyes (14%). Low initial visual acuity, RD, arid deep vitrectomy were detected as statistically significant risk factors for final visual acuity of 20/200 or less. Positive APD and deep vitrectomy were statistically significant risk factors for final RD. BCYA of 20/300 or less, laceration size more than 10 mm, scleral and corneoscleral lacerations, vitreous prolapsed, vitreous hemon-hage, RD, and sharp injury were risk factors for enucleation. Conclusion: Low BCYA, positive APD, and deep vitrectomy are risk factors for final low visual acuity. RD and deep vitrectomy are risk factors for final RD. Low initial visual acuity, larger scleral lacerations, positive APD, and RD are negative factors for ocular survival.

Purpose: To compare the effect of implantation of a single-piece hydrophilic foldable acrylic intraocular lens (IOL) with rectangular optic edge and a single-piece polymethy1 methacrylate (PMMA) IOL with rounded optic edges on posterior capsular opacification (PCO). Methods: This randomized clinical trial study comprised 74 eyes with senile cataract in an otherwise normal eye in patients older than 50 years. Patients were randomized to receive hydrophilic foldable acrylic or PMMA IOLs. The operations were performed using standard phacoemulsification by the same surgeon. Patients were followed for at least 9 months. PCO was graded according to slit lamp examination (retroillumination) and best corrected visual acuity (BCYA). The PCO values and BCYA at 6 and 9 months after surgery, capsulorrhexis diameter, and post operative inflammation were compared between the two groups. Results: From 74 patients enrolled in the study, 56 patients including 28 in each group, had complete follow up and examinations. Mean age was 67.64±7.71years. Six months after surgery visually significant PCO occurred in 2 patients (7.1%) in the acrylic group and 7 patients (25%) in the PMMA group. (P=0.001) At 9 months YAG capsulotomy was performed in one eye (3.6%) in the acrylic group and 3 eyes (10.7%) in the PMMA group. (P=0.61) There was no correlation between PCO with age (P=0.13) or capsulorrhexis diameter (P= 0.8). Conclusion: Hydrophilic acrylic IOLs cause less PCO than PMMA IOLs. However, the results can not attributed to the IOL material alone as they show the importance of both material and design.

Purpose: TO compare the efficacy and safety of two local anesthetic methods; retrobulbar anesthesia and parabulbar anesthesia using PTFE intravenous cannula without needle in extracapsular cataract surgery. Method: A randomized prospective partially blind study was conducted on 66 eyes of 66 patients with senile cataract who were scheduled for ECCE and PC IOL surgery. After randomization, 35 patients received retrobulbar anesthesia and 31 received parabulbar anesthesia. lOP was easured preoperatively and 1,5, 15, and 30 min after injection. Akinesia was measured 1,5, 15, and 30 in after injection. Akinesia was graded as 0, 1, 2, in which zero means complete absence of movement or minimal movement around primary position; 1 means relative akinesia: residual movement of one muscle or relative reduction of muscle movement in all directions; and 2 means no akinesia. Pain was measured using a 10 point visual analog scale immediately after injection. Parabulbar anesthesia was performed with an IV cannula, gauge 22,25 mm length, made from PTFE (poly tetra fluoro ethylene). The IV cannula sheath was used and its needle was discarded. Results: Patients included 47% female and 53% male subjects. Mean age was 68 yr. There was no significant difference in the age and sex distribution and preinjection intraocular pressure between two groups. Akinesia was significantly more complete at all times after injection in group with parabulbar anesthesia. IOP was significantly higher at all times after injection in eyes with parabulbar anesthesia. Pain sensation was not significantly different between two groups. Major complications were not seen in any groups. Minor complications including chemosis (32%) and hemorrhage at site of peritomy (95%) were seen in parabulbar group. Conclusion: Parabulbar anesthesia produces better and faster akinesia than retrobulbar anesthesia but it can cause more IOP elevation that should be considered in patients with compromised ocular circulation. This needle-free variation of parabulbar anesthesia in an  effective and safe technique for local anesthesia in cataract surgery.

Purpose: To evaluate changes in indications of corneal transplantation at Labbafinejad Medical Center during 2001-2003.Methods: Records of 563 from 684 patients who had undergone corneal transplantation from Oct. 2001 to Oct. 2003 were evaluated. All the procedures were performed by corneal surgeons and fellows. Findings: There were 292 male (51.9%) and 217 female (48.1%) subjects ranging in age from 2 months to 97 years. Keratoconus (KCN) was the most common cause (27.3%) of corneal rafting, and other causes were as follows: herpes simplex keratitis (11.7%), regraft (11.5%),bacterial keratitis (6.5%), trachoma keratopathy (5.5%), macular corneal dystrophy (5.5%), corneal opacity of unknown cause (4%), trauma (2%), congentital hereditary endothelial dystrophy (2%), fuch's endothelial dystrophy (1.9%), fungal keratitis (1.9%), and other causes (7.2%). Conclusion: As in our previous report, KCN is the leading cause of corneal graft at Labbafinejad Medical Center. Infectious keratitis is the second and fuch's endothelial dystrophy is the least common indication. Herpes simplex keratitis has decreased which may be due to better medical management of the disorder. The rate of regraft has not changed.

Purpose: To detern1ine the long-term visual outcomes and complications of penetrating keratoplasty (PK) performed for keratoconus. Methods: Hospital records of patients with keratoconus who underwent PK at the Ophthalmology Center of Shaheed Sadoughi, Yazd, Iran, during 1992-2003 were reviewed. We studied records of 84 PK procedures in 72 keratoconus patients. Data including best corrected visual acuity (BCVA), type of correction, type of suturing, incidence of rejection, keratome try, and postoperative complications were reviewed and analyzed at 12 and 18 months.Results: Best corrected visual acuity (BCVA) improved from 20/40 at month 12 to 20/30 at month 18. (P< 0.0001) Mean spherical refraction was -4.81 diopter (D) at 12 month. BCVA was 20/40 or better in 71.4% of the eyes at last follow-up and 65.5% of the eyes were corrected by spectacles. Mean preoperative corneal power by keratometry was more than 52 D in 78.8% of eyes and mean postoperative corneal power was 46 ± 2.5 D at the end of the first week. The only significant predictor of post operative astigmatism was donor-recipient disparity. Allograft rejection was seen in 26.1% of cases and there were two graft failures due to allograft reaction. Overall 19% of cases required keratorefractive surgery. At last follow-up, spherical equivalent was -2.50 ± 1.15 D, corneal astigmatism was 3.8±1.9 D, and BCVA was 0.26± 0.14 Log MAR. Mean spherical equivalent of rcfractive error was bettcr with 0.25 mm donor-recipient differencc (-3.1±2.5 D) in comparison to 0.50 mm difference (-4.2 ± 2.8 D). (P< 0.001) Conclusions: Penetrating keratoplasty is a good treatment option for keratoconus. Our data demonstrated that the majority of patients require optical correction for functional VA after keratoplasty.

Purpose: To determine whether adding 2% topical cyclosporine (CSA) to local and systemic steroids in treatment of endothelial corneal allograft rejection improves the outcome. Methods: A prospective randomized treatment trial was carried out on 40 consecutive corneal graft recipients, presenting with the first episode of endothelial graft rejection in two groups. Group one (20 patients) received topical steroid eye drops and oral prednisolone (1 mg/kg). Group two (20 patients) received the same topical and systemic therapy plus 2% cyc1osporine eye drops. The patients were followed up for three months and their clinical outcomes were evaluated by the rates and time for reversal of rejection. Results: In group one, 14 (70%) cases had total reversal of graft rejection episode which started within a mean period of three days. but in the CSA group, it occurred in 18 (90%) cases which started within a mean period of 1.5 days (P=0.21).Among patients who sought treatment early (< 6 days). survival rates were 85% and 100%, respectively (P=0.2). In high risk patients, the rejection reversal rate was 66% in CSA group and 25% in the control group (P=0.5). Conclusion: Addition of 2% CSA eye drop to topical and systemic steroids may improve the rates of graft rejection reversal. It may also decrease the interval between initiation of treatment and improvement of clinical signs.

Purpose: To determine bacterial contamination of corneas and corneal storage media provided from the Eye Bank of I.R. Iran to Rasool Akram Medical Center. Methods: This descriptive study was performed on 70 corneoscleral rims and corneal storage media. One milliliter of corneal storage media and the corneoscleral rim were sent to microbiology laboratory at the time of penetrating keratoplasty and specimens were cultured on blood agar, EMB agar, and thioglycolate broth.Results: No organism growth was observed after 72 hours in any of70 storage media or corneoscleral rims. Conclusion: The aseptic protocol of the Eye Bank of LR. Iran is proper in term of tissue preparation, preservation, and transferring of corneal graft is proper.

Purpose: To report a case who had undergone LASIK in his right eye and PRK in the fellow eye for correction of equivalent myopia but developed progressive post-operative keratectasia only in the right eye. Patient and findings: A 30-year-old man had undergone LASIK in right eye 3 years ago for correction of refractive error of -1.75 -1.50@48° and PRK in left eye 2 years ago for correction of refractive error of -1.00 -1.75@100°. Preoperative pachymetry was 447 µm in the right eye and 446 µm in left eye. However, post-operative pachymetry decreased to 341 µm in the right and 384 µm in the left eye, but only the right eye revealed progressive corneal ectasia that led to severe visual loss (20/400). Conclusion: PRK may be a better choice for surgical correction of low amounts of myopia due to lack of flap creation; a factor that may weaken the anterior corneal structure and subsequently lead to progressive keratectasia. However, it is prudent to avoid any refractive surgery in eyes with central corneal thickness less than 500 /lm.

Purpose: To report a case of eviceration because of necrotizing scletitis 3 years after ptrygium surgery with mitomycin C. Patient and findings: A 62-year-old diabetic woman with history of bilateral ptrygium surgery with MMC 3 years ago, was referred due to severe pain in her right eye. Visual acuity was counting fingers at 2 m. There was thinning and melting of the sclera with uveal prolapse that was more severe in the right eye. The patient was admitted with a diagnosis of necrotizing scleritis. She received topical and systemic medications, but the inflammatory process progressed. Evisceration of the right eye was performed.Conclusion: Adjunctive use of MMC can produce severe complications threatening visual acuity includes necrotizing scleritis which may eventually lead to evisceration.

Purpose: To report two sisters with congenital myasthenia syndrome (CMS) masquerading as myasthenia gravis.Patients and findings: Two six and seven years old sisters presented with variable strabismus, ptosis, and fatigue. All symptoms were aggravated with exercise and improved with rest. Intramuscular prostigmin injection decreased their symptoms. A diagnosis of CMS was made according to early onset (infancy), familial pattern, and lack of serum antibodies. Oral neostigmin was begun for treatment. Conclusion: Although CMS is a rare disorders, they should be considered in all cases with variable strabismus and ptosis.