Retinal Damage from Laser Pointer Misuse - Case Series from the Military Sector in Oman.

Laser pointers are practical and safe training tools when used properly. If used incorrectly they can cause ocular damage, potentially resulting in devastating vision loss. The ocular and visual morbidity can result in significant expenses for medical care and inability to work (temporarily or permanently) for civilians and military personnel. We present three cases of soldiers who experienced vision loss following exposure to laser pointers, while celebrating successful football game.

Bilateral hypermetropia, myelinated retinal nerve fibers, and amblyopia.

A 14-year-old hyperopic female with poor vision in both eyes was evaluated for ophthalmic and systemic diseases. The patient had bilateral retinal fiber myelination and greater vision loss in the more hyperopic eye. This was a rare case of reverse Straatsma syndrome, the clinical presentation which may be accompanied with significant vision loss.

Macular function in prediabetic and diabetic Omani adults: a microperimetric evaluation.

PURPOSE: To assess if functional visual loss preceded structural changes or vice versa in diabetic patients by evaluating the macular function in prediabetic patients and in diabetic patients with varying grades of retinopathy and comparing the findings with those of age-matched healthy controls by means of microperimetry. METHODS: Retinal sensitivity, fixation pattern, and test response were evaluated in 25 prediabetic patients (50 eyes), 25 diabetic patients (50 eyes), and 25 age-related normal nondiabetic patients (50 eyes) using Nidek microperimetry. The diabetic patients were classified into 3 groups on the basis of clinical and fundus fluorescein angiographic evidence: group 1 = no clinical or angiographic evidence of retinopathy, group 2 = background retinopathy only, group 3 = with macular edema. Classification of retinopathy was based on Early Treatment Diabetic Retinopathy Study standards. Statistical analysis was conducted by Fisher exact test. RESULTS: In diabetic patients, 20 eyes (40%) had no clinical or angiographic evidence of retinopathy, 13 eyes (26 %) had background changes, and 17 eyes (34%) had macular edema. Statistically significant difference in the fixation pattern, test response, and retinal sensitivity was noted in the diabetic and the prediabetic patients when compared to the controls. CONCLUSIONS: Significant loss of macular function in the eyes of prediabetic subjects was noted. These preliminary findings probably support the hypothesis that neurodegeneration precedes microangiopathy.

Molecular analysis of CYP1B1 in Omani patients with primary congenital glaucoma: a pilot study.

PURPOSE: To screen cytochrome P4501B1 (CYP1B1) for causative mutations in Omani patients with a clinical diagnosis of primary congenital glaucoma (PCG) METHODS: Nine PCG families were recruited for the study. All patients underwent detailed clinical examinations to confirm the diagnosis of PCG. The families of index patients were also examined. Genealogical information was obtained by pedigree analysis. The primary candidate gene, CYP1B1, was amplified from genomic DNA, sequenced, and analyzed in patients to identify the disease-causing mutations. RESULTS: Eight of the nine PCG families were consanguineous (89%). Molecular analysis of CYP1B1 showed three distinct mutations, p.G61E, p.D374N, and p.R368H, in seven of nine unrelated PCG index patients (78%). Six patients had homozygous mutations and one had a compound heterozygous mutation. Causative mutations were not identified in two families. In family 4, the index patient was found to be heterozygous for the p.E229K variant. In family 6, although affected individuals were found to be homozygous in the CYP1B1 region, no mutation could be identified. CONCLUSIONS: This study indicates that CYP1B1 could be the predominant cause of PCG in the Omani population (78%). Omani PCG patients show allelic heterogeneity. Further studies are needed to delineate the spectrum of CYP1B1mutations in Omani PCG families and to identify new or modifier genes contributing to the manifestations of PCG in this region.

Visual rehabilitation by scleral fixation of posterior chamber intraocular lenses in Omani children with aphakia.

BACKGROUND AND OBJECTIVE: To report indications and outcomes of scleral-fixated posterior chamber intraocular lenses (PC IOLs) in Omani children with aphakia. PATIENTS AND METHODS: Patients with aphakia who were younger than 16 years, unsuitable for spectacle or contact lens correction, and without capsular support underwent an anterior vitrectomy and 10-0 polypropylene inside-out scleral fixation ofa PC IOL. RESULTS: Scleral-fixated PC IOLs were implanted in 28 eyes of 24 patients. Group A comprised 10 (36%) eyes with congenital cataract and 3 (11%) eyes with ectopia lentis and group B comprised 15 (53%) eyes with traumatic cataract. The mean age at implantation was higher in group A (10.5 years) than in group B (7.3 years). Visual acuity improved in 17 of 28 (61%) eyes and remained at the preoperative levels in 11 of 28 (39%) eyes. Mean postoperative refraction was within +/- 2.0 diopters of the predicted refraction in 19 of 28 (68%) eyes. Complications included temporary intraocular pressure increase, vitreous hemorrhage, and iris capture with lens malposition. CONCLUSION: Scleral-fixated PC IOLs are beneficial for children with aphakia without posterior capsular support who are lacking other means for visual rehabilitation. Patients with traumatic cataract and lens dislocation are more likely to experience an improvement in visual acuity postoperatively than patients with congenital cataract. However, this procedure is technically more difficult than routine PC IOL implantation and potentially carries greater risks.

In vivo morphometry of corneal endothelial cells in pseudoexfoliation keratopathy with glaucoma and cataract.

BACKGROUND: This study was designed to define correlations between in vivo morphometric and demographic data of pseudoexfoliation (PEX) keratopathy patients from Omani Arab origin with cataract and glaucoma. METHODS: In a non-randomized controlled comparative case series, 69 adult patients (43 males and 26 females) with 78 cataract and 48 glaucoma eyes with corneal PEX material were assessed by confocal biomicroscopy (Confoscan 2, Nidek) and values compared to normative US and Omani Arab population values. Descriptive statistics. RESULTS: The mean age of glaucoma patients was 60.81 +/- 8.33 years, of cataract patients 64.65 +/- 6.67 years; 109/126 eyes (74%) were from patients >60 years old (14 glaucoma and 95 cataract eyes). Age-adjusted endothelial cell counts were similar to normative values in 108/126 eyes (85.7%). Polymegathism and pleomorphism were abnormal in 124/126 (98.4%) and 122/126 eyes (96.8%), respectively. The correlation of pleomorphism and polymegathism with males (R(2) = 0.6378, p = 0.05) was stronger than with females (R(2) = 0.6024, p = 0.06), and stronger for patients <60 years (R(2) = 0.7268, p = 0.01) than >60 years old (R(2) = 0.5805, p = 0.01). Cataracts: Endothelial cell counts were normal (mean 2,483 +/- 511.2). Pleomorphism was 33.12 +/- 11.44% and different from Omani Arab controls (p < 0.01), polymegathism 58.14 +/- 16.58% (p <0.01). Glaucomas: Endothelial cell counts were normal (mean: 2,438 +/- 503). Pleomorphism and polymegathism were 37.09 +/- 12.43% (p < 0.01) and 59.69 +/- 16.79% (p < 0.01), respectively. Pleomorphism and polymegathism were more associated with glaucomas (R(2) = 0.7652, p = 0.02) than with cataracts (R(2) = 0.6041, p = 0.06). CONCLUSIONS: Endothelial cell polymegathism and pleomorphism in PEX keratopathy with glaucoma is more frequently associated with age <60 years and male gender than with cataract.

Subjective and quantitative measurement of wavefront aberrations in nuclear cataracts - a retrospective case controlled study.

PURPOSE: To measure, quantify and compare Ocular Aberrations due to nuclear cataracts. SETTING: Department of ophthalmology and school for ophthalmic technicians, college of medicine and health sciences, Sultan Qaboos University, Muscat, Oman. DESIGN: Retrospective case controlled study. METHODS: 113 eyes of 77 patients with nuclear cataract (NC) were recruited from outpatient clinic of a major tertiary referral center for Ophthalmology. Patients having NC with no co-existing ocular pathologies were selected. All patients were subjected to wavefront aberrometry (make) using Hartmann-Shack (HS) aberrometer. Consents were taken from all patients. Higher order Aberrations (HOA) were calculated with Zernike polynomials up to the fourth order. For comparison 28 eyes of 15 subjects with no lenticular opacities (control group) were recruited and evaluated in an identical manner. No pupillary mydriasis was done in both groups. RESULTS: Total aberrations were almost six times higher in NC group compared to control (normal) subjects. The HOA were 21 times higher in NC group, and coma was significantly higher in NC eyes compared to normal (control) group. The pupillary diameter was significantly larger in control group (5.48mm +/- 1.0024, p<.001) compared to NC (3.05mm +/- 1.9145) subjects (probably due to younger control age group). Amongst Zernike coefficients up to fourth order, two polynomials, defocus (Z(2) (0)) and spherical aberration (Z(4) (2)) were found to be significantly greater amongst NC group, compared to normal control group. CONCLUSION: Nuclear cataracts predominantly produce increased defocus and spherical aberrations. This could explain visual symptoms like image deterioration in spite of normal Visual acuity.

Visually evoked potentials after panretinal photocoagulation in omani patients with uncontrolled diabetes mellitus.

AIM: To report on the changes of latency and amplitudes of the pattern VEP in patients with uncontrolled diabetes mellitus II and I before and after panretinal laser treatment. DESIGN: Single center hospital based comparative study. METHODS: One hundred eyes of patients with proliferative diabetic vitreoretinopathy, and HbA1C ≥ 10 percent were subjected to Pattern Visually Evoked Potentials (Medtronic keyopint system, Nicolet) prior to and 4 weeks after PRP. Results were compared to age-matched non-diabetic controls. Chi-Square test, and paired 't' test were used for statistical analysis. RESULTS: Preoperative mean VEP amplitude was 8.35mV±3.71, and not significantly different to the control group (mean 10.51mV±3.34) (chi square test p=1). Mean preoperative P100 latency was 106.93±7.90ms and significantly different to the control group (103.21±7.65ms) (paired t-test p=0.001). After laser treatment, VEP amplitudes decreased in 48/100 eyes (mean total 5.11mV±2.4), and P100 latency increased in 75/100 eyes (mean total 110.47±7.35ms). CONCLUSION: In this study, PRP was followed by a significant decrease in VEP amplitudes in 48 percent and increase in latency in 75 percent of eyes.

Visual rehabilitation by scleral fixation of posterior chamber intraocular lenses in amblyopic aphakic children.

BACKGROUND/AIMS: To report on the outcome of scleral fixated posterior chamber intraocular lens (S-IOL) implantation in aphakic amblyopic children after 1 year. METHODS: Amblyopic children with aphakia after traumatic and congenital cataract surgery unsuitable for spectacle or contact lens correction were operated with an anterior vitrectomy and inside-out double thread scleral fixation of an Alcon CZ70BD pcIOL. Refraction and vision was compared after 12 months. RESULTS: From 2001-2006, 23 S-IOLs were implanted in 16 children (19 unilateral, 4 bilateral) aged 2-16 years: 10 eyes with traumatic [Group A], and 13 eyes with congenital cataracts including 3 eyes with ectopia lentis [Group B]. Preoperative UCVA compared to postoperative UCVA improved in 9/10 eyes in group A and 12/13 eyes in group B. Preoperative BCVA compared to postoperative UCVA improved in 9/10 eyes (90 percent) in group A and 4/13 eyes (31 percent) in group B. Mean age at surgery in group A was 6.8 years (1.5-16yrs) and in group B 10.5 years (4-16 years). More than one year elapsed in 2/10 eyes of group A and 8/13 eyes in group B. Postoperative refraction was within 2.0D of target in 17/23 eyes. Complications included temporary IOP rise in 2, vitreous hemorrhage in 1, and iris capture in 3 eyes. Two eyes required revision surgery. CONCLUSION: S-IOL implantation may be beneficial for aphakic children lacking other means for visual rehabilitation to improve vision. Amblyopia may be improved in most trauma, but only few congenital cataract eyes.

Quantitative and qualitative corneal endothelial morphology of omani patients with pseudoexfoliation syndrome.

OBJECTIVE: Pseudoexfoliation (PEX) syndrome is one of the leading causes of secondary open angle glaucoma and blindness. This study explored whether in PEX eyes, preoperative changes in corneal endothelial cell morphology might be a risk factor for postoperative corneal decompensation. METHODS: One hundred twenty six eyes of 69 preoperative cataract patients (43 males, 26 females) were enrolled in this cross-sectional study from the Ophthalmology Department at Sultan Qaboos University Hospital between 2003-2005. All patients were subjected to confocal biomicroscopy. RESULTS: The mean age of patients with PEX eyes was 63.2 years. One hundred and eight (85.7%) eyes with PEX had endothelial cell counts within the normal range (1650-3500/mm(2)). The qualitative morphology of the endothelium of PEX corneas was highly abnormal in term of polymegathism and pleomorphism. Twelve eyes had endothelial cell counts higher than normal for that age group. Only 6 eyes had endothelial cell counts lower than normal. The mean value for the pleomorphism was found to be significantly lower than normal and for polymegathism significantly more than normal. The relationship between pleomorphism and polymegathism was stronger for males than for females and stronger for patients under 60 years than patients over 60 years. The same relationship between pleomorphism and polymegathism showed a stronger relationship for the glaucoma group as compared to the non-glaucoma group. CONCLUSION: This study revealed that corneal decompensation in PEX eyes can occur in presence of abnormalities in polymegathism and pleomorphism, even when the endothelial cell counts may be normal.

[Infection immunology in silicone hydrogel contact lenses for continuous wear--a review]. / Infektionsimmunologie bei Silikonhydrogelkontaktlinsen mit verlängerter Tragezeit--- eine Ubersicht.

BACKGROUND: The patient's wish for permanent refractive solution and optimal comfort must be weighed against the risk of infections. In order to meet these wishes and the demand for minimising associated risks, hyperoxygen-transmissible silicone hydrogel contact lenses have been developed. METHODS: Colonisation and sensitivity to antibiotics of bacteria in vitro, expression of bacterial ligands of the corneal epithelium (rabbit model), and the morphology of complications in patients have been reported to characterise HOTL. RESULTS: Bacterial adherence to hydrophobic silicone elastomers is low. The reduction of sensitivity towards antibiotics is higher for PMMA-adherent bacteria with respect to the conventional antibiotics compared to the silicone-elastomer adherent bacteria. Colonising bacteria are not significantly different in asymptomatic CL wearers concerning CFU and species: asymptomatic: CNS (54 vs. 47 %), propioni- (43 vs. 48 %), coryne- (6 vs. 10 %) and gram-negative bacteria (2 vs. 3 %), S. aureus (2 vs. 1 %), and in patients with keratitis are not significantly different concerning species: CLARE (H. influenzae, S. pneumoniae), CLPU (S. aureus, S. pneumoniae), IK (P. aeruginosa), however, concerning the CFU (gram-negative) 23.7 % (keratitis) vs. 3.8 %, (asymptomatic), S. pneumoniae 7.6 % vs. 0.6 %. The epithelial expression of bacterial ligands like WGA is lower for HOTL (3230 p/750 micro) than for low oxygen-transmissible (4611 p/750 micro) consistent with a decreased adherence of pseudomonas of 5.31 - 5.98 vs. 5.9 - 7.81 bacteria/cell. Asymptomatic morphological anomalies and keratitis are less frequent in HOTL. Apoptosis-induced desquamation and the central epithelial thickness decreased. In a one-year study of 504 patients wearing continuous wear HOTL for 30 days, corneal staining was seen in 10.6 vs. 10.5 % 30-day 7 day extended wear, infiltrates in 2.3 vs. 4.6 %, epithelial oedema in 3.6 vs. 2.0 % und tarsal conjunctival anomalies in 3.0 vs. 1.6 %. Individual reports on infectious keratitis in HOTL wearers have been published. CONCLUSIONS: Fewer morphological anomalies and a decreased incidence of infections (on the basis of duration of wear) can be associated with the higher oxygen transmission of HOTL. From the clinical point of view, colonisation of HOTL with the same bacterial species as in conventional biomaterials, and the extended wear demand clear patient counseling and vigilant follow-up by an ophthalmologist.

[Incidence of ocular manifestations in patients with histologically confirmed systemic sarcoidosis]. / Augenmanifestationen bei Patienten mit histologisch gesicherter Sarkoidose.

BACKGROUND: Intraocular findings in sarcoidosis were described by US studies with 35 % anterior uveitis, 25 % posterior uveitis and 20 - 30 % for late complications in case of first presentation. We report on the spectrum and diagnostic possibilities in 38 German patients. PATIENTS AND METHODS: 38 patients (68 eyes) aged 11 - 58 years (average 42.7 y), who suffered of intraocular manifestations in histological confirmed systemic sarcoidosis (1987 - 1997), were completely evaluated retrospectively. For additional diagnostic tools fluorescein angiography, optical coherence tomography, nuclear magnetic resonance tomography and measurements of angiotensin-converting enzyme, lysozyme and calcium in serum were performed. RESULTS: 15 patients (22 eyes = 32.4 %) had anterior uveitis: granulomatous keratouveitis (10 eyes), granulomas of the iris (6), granulomas of the trabecular meshwork (3) and 22 patients (42 eyes = 61.8 %) an intermediate and posterior uveitis: granulomatous perivasculitis (18 eyes), cystoid maculopathy (8), pars planitis (6), neuroretinitis (4), optic neuritis (3), choroiditis (3). Late complications in case of first presentation were found in 22 patients (39 eyes = 57.4 %): posterior synechiae 14 x, secondary glaucoma 10 x, cataracta complicata 8 x, optic atrophy 6 x, intraocular calcification 1 x. CONCLUSION: Compared to previous studies with heterogeneous ethnic composition, intraocular inflammations with confirmed sarcoidosis in German patients show more than 60 % involvement of the posterior segment. We may speculate on the reasons for these discrepancies as being due to ethnic reasons, age and long-term follow-up. In case of typical ocular signs of sarcoidosis, treatment should be started immediately even without histological confirmation. In some cases histological confirmation is successful 8 years after first presentation.