Risk Factors for Glaucoma Diagnosis and Surgical Intervention following Pediatric Cataract Surgery in the IRIS® Registry

PURPOSE

To compare demographic and clinical factors associated with glaucoma following cataract surgery (GFCS) and glaucoma surgery rates between infants, toddlers, and older children using a large, ophthalmic registry.

DESIGN

Retrospective cohort study.

PARTICIPANTS

Patients in the IRIS® Registry (Intelligent Research in Sight) who underwent cataract surgery at ≤ 17 years old and between January 1, 2013 and December 31, 2020.

METHODS

Glaucoma diagnosis and procedural codes were extracted from the electronic health records of practices participating in the IRIS Registry. Children with glaucoma diagnosis or surgery before cataract removal were excluded. The Kaplan-Meier estimator was used to determine the cumulative probability of GFCS diagnosis and glaucoma surgery after cataract surgery. Multivariable Cox regression was used to identify factors associated with GFCS and glaucoma surgery.

MAIN OUTCOME MEASURES

Cumulative probability of glaucoma diagnosis and surgical intervention within 5 years after cataract surgery.

RESULTS

The study included 6658 children (median age, 10.0 years; 46.2% female). The 5-year cumulative probability of GFCS was 7.1% (95% confidence interval [CI], 6.1%-8.1%) and glaucoma surgery was 2.6% (95% CI, 1.9%-3.2%). The 5-year cumulative probability of GFCS for children aged < 1 year was 22.3% (95% CI, 15.7%-28.4%). Risk factors for GFCS included aphakia (hazard ratio [HR], 2.63; 95% CI, 1.96-3.57), unilateral cataract (HR, 1.48; 95% CI, 1.12-1.96), and Black race (HR, 1.61; 95% CI, 1.12-2.32). The most common surgery was glaucoma drainage device insertion (32.6%), followed by angle surgery (23.3%), cyclophotocoagulation (15.1%), and trabeculectomy (5.8%).

CONCLUSIONS

Glaucoma following cataract surgery diagnosis in children in the IRIS Registry was associated with young age, aphakia, unilateral cataract, and Black race. Glaucoma drainage device surgery was the preferred surgical treatment, consistent with the World Glaucoma Association 2013 consensus recommendations for GFCS management.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Risk of visual axis opacification in infants with and without primary IOL implantation after congenital cataract surgery performed during the first 4 months of age

PURPOSE

The study evaluates the rate of postoperative formation of a pupillary membrane (PM) and posterior visual axis opacification (PVAO) in infants with and without primary IOL implantation during the first 4 months of infancy.

METHODS

Medical records for 144 eyes (101 infants) operated between 2005 and 2014 were evaluated. A posterior capsulectomy and anterior vitrectomy were performed. Primary IOL implantation was performed in 68 eyes, while 76 eyes were left aphakic. There were 16 bilateral cases in the pseudophakic group and 27 in the aphakic group. The follow-up period was 54.3 ± 21.05 months and 49.1 ± 18.60 months, respectively. Fisher's exact test was used for statistical analysis. The two-sample t-test with equal variance was used to compare surgery age, follow-up period and time intervals of complications.

RESULTS

The mean age of surgery was 2.1 ± 0.85 months in the pseudophakic and 2.2 ± 1.01 months in the aphakic group. PM was diagnosed in 40% pseudophakic and 7% aphakic eyes. A second surgery for PVAO was performed in 72% pseudophakic and 16% aphakic eyes. Both were significantly higher in the pseudophakic group. In the pseudophakic group, the number of PVAO was significantly higher in infants operated before 8 weeks of age compared to surgery age 9-16 weeks. The frequency of PM was not age-dependent.

CONCLUSION

Although it remains feasible to implant an IOL during the primary surgery, even in very young infants, there should always be solid arguments for this decision since it puts the child at higher risk of repeated surgeries under general anaesthesia.

Risk Factors for Retinal Redetachment After Silicone Oil Removal: A Systematic Review and Meta-Analysis

BACKGROUND AND OBJECTIVE

This systematic review and meta-analysis was made to measure risk factors for retinal redetachment (re-RD) after silicone oil removal (SOR) in a quantitative method.

PATIENTS AND METHODS

A comprehensive literature review relating to risk factors for re-RD after SOR was conducted before March 2017. Odds ratio (OR) with 95% confidence interval (CI) was calculated after data combination.

RESULTS

Sixteen studies were included, and risk factors with significant differences found between the re-RD and control groups are as follows: aphakic eye (OR = 1.50), high myopia (OR = 2.47), previous failed retinal surgery (OR = 1.71), and ocular trauma (OR = 3.52). Peripheral 360° laser retinopexy (OR = 0.40) and scleral encircling band (OR = 0.58) were found to be protective factors of re-RD after SOR.

CONCLUSION

Aphakic eye, high myopia, previous failed retinal surgery, ocular trauma, lack of 360° laser, and scleral encircling band were possible risk factors relating to the occurrence of re-RD after SOR. [Ophthalmic Surg Lasers Imaging Retina. 2018;49:416-424.].

Motor skills of children with unilateral visual impairment in the Infant Aphakia Treatment Study

AIM

To assess motor functioning in children aged 4 years 6 months enrolled in the Infant Aphakia Treatment Study, and to determine contributions of visual acuity and stereopsis to measured motor skills.

METHOD

One hundred and four children (53% female) with unilateral aphakia randomized to intraocular lens or contact lens treatment were evaluated at 4 years 6 months (age range 4y 6mo-4y 11mo) for monocular recognition visual acuity, motor skills, and stereopsis by a traveling examiner masked to treatment condition. Motor skills were assessed with the Movement Assessment Battery for Children--Second Edition (MABC-2). Visual acuity was operationalized as log10 of the minimum angle of resolution (logMAR) value for treated eye, best logMAR value for either eye, and intraocular logMAR difference.

RESULTS

Student's t-tests showed no significant differences in MABC-2 scores between the intraocular lens and contact lens groups. The mean total score was low (6.43; 18th centile) compared with the normative reference group. Motor functioning was not related to visual acuity in the treated eye or to intraocular logMAR difference, but was predicted in a regression model by the better visual acuity of either eye (usually the fellow eye), even after accounting for the influence of age at surgery, examiner, orthotropic ocular alignment, and stereopsis.

INTERPRETATION

Children with unilateral congenital cataract may have delayed motor functioning at 4 years 6 months, which may adversely affect their social and academic functioning.

A modified technique of pupillary stretching

In eyes undergoing vitreoretinal surgery up to now dilatation of a miotic pupil by the pupillary stretching technique could be performed only in aphakic eyes. Now a new needle with a tiny eye at its tip has been developed. With the help of this needle, 4 iris loop sutures can be led around the iris only passing the anterior chamber. This permits pupillary stretching also in phakic eyes. The modified technique was used on 3 phakic and 2 aphakic eyes.

Anatomical and functional outcome following primary retinal re-attachment surgery in phakic and pseudophakic rhegmatogenesis retinal detachment

BACKGROUND

Rhegmatogenous Retinal detachment (RRD) is relatively unusual in general population: annual incidence is 1:10,000. Objective of this study was to compare the anatomical and functional outcome of primary retinal re-attachment surgery in phakic and pseudophakic eyes.

METHODS

A case series comparative study was carried out at Al-Ibrahim Eye Hospital, Karachi from July 2008 to June 2009. A total of 71 eyes of 69 patients either phakic (group-I) or pseudophakic (group-II) rhegmatogenous retinal detachment (RRD) with proliferative vitreoretinopathy (PVR) up to grade C-3 were included in the study. Eyes with RRD with PVR C-4 and above, corneal opacity and previous posterior segment surgery were excluded. Pars plana vitrectomy (PPV) or scleral buckling procedure (SBP) was performed as a primary re-attachment surgery. Patients were followed for at least 6 months. Anatomical (retinal reattachment) and functional outcome (best corrected visual acuity) was noted at each follow up.

RESULTS

Anatomical outcome (retinal reattachment) was similar in group-I (93.02%) and group-II (92.86%) eyes (p = 0.88). Best corrected visual acuity (functional outcome) of 6/69 (see symbol) 6/18 was achieved in 46.5% in Group-I and 10.7% in Group-II. Raised intraocular pressure (LOP) was observed as most common complication.

CONCLUSION

Primary retinal re-attachment surgery either in phakic (group-I) or pseudophakic (group-II) eyes have similar anatomical outcome but functional outcome depends upon the status of macula at the time of surgery and level of proliferative vitreoretinopathy (PVR).

Perinatal ablation of the mouse lens causes multiple anterior chamber defects

PURPOSE

The purpose of this study was to reassess the role of the lens as an "embryonic organizer" of ocular tissues.

METHODS

We ablated the lens in mice by lens-specific expression of an attenuated version of diphtheria toxin A subunit(Tox176) driven by a modified crystallin promoter. Alterations in the differentiation programs of ocular tissues were examined by hematoxylin and eosin staining, in situ hybridization, and immunohistochemistry.

RESULTS

Transgenic mice in the family OVE1757 exhibited severe microphakia. Apoptotic lens fibers were seen by embryonic day 15 (E15) and the lenses were completely ablated by post natal day 8. Multiple defects were seen in the anterior chamber. Corneal endothelial cells did not differentiate properly. The mesenchymal cells that would normally give rise to the endothelial layer were found to express N-cadherin, but they failed to form tight junctions and undergo a mesenchymal-to-epithelial transition. Although early specification of the presumptive ciliary body and iris was detected, subsequent differentiation of the iris was blocked. No dramatic changes were seen in the development of the retina.

CONCLUSIONS

These results support the hypothesis that an intact lens is essential for proper differentiation of both the corneal endothelium and the iris and that the lens "organizes" the development of tissues in the anterior chamber.

Central corneal thickness: congenital cataracts and aphakia

PURPOSE

To evaluate central corneal thickness (CCT) in normal children (controls) and in those with cataracts, pseudophakia, and aphakia.

DESIGN

Prospective, observational case series.

METHODS

CCT was measured in 369 eyes of 223 children. Subjects with glaucoma, anterior segment abnormalities, or intraocular pressure of more than 30 mm Hg were excluded. Group means were compared for controls and for eyes with pediatric cataracts, pseudophakia, and aphakia.

RESULTS

The mean CCT of eyes with cataracts was more than that of controls (574 +/- 54 microm [n = 46] and 552 +/- 38 microm [n = 230], respectively; P = .001). After excluding from the cataract group those eyes with aniridia, Down syndrome, Marfan syndrome, or glaucoma surgery, the mean CCT (564 +/- 34 microm [n = 36]) was no longer greater than that of controls (P = .07). The mean CCT of pseudophakic eyes (598 +/- 56 microm [n = 29]) was greater than the mean CCT of controls (P < .001) and was similar to the mean CCT of eyes with cataracts (P = .06). The mean CCT of aphakic eyes (642 +/- 88 microm [n = 64]) was greater than the mean CCT of controls (P < .001), eyes with cataracts (P < .001), and eyes with pseudophakia (P = .003).

CONCLUSIONS

In the absence of factors known to affect CCT (Down syndrome, Marfan syndrome, and aniridia), CCT is similar in eyes with pediatric cataracts and normal controls and increases after cataract surgery.

Binocular membranous cataract associated with binocular retinal detachment

A 36-year-old man with a history of consanguineous marriage between his parents presented with bilateral membranous cataract that was complicated by bilateral rhegmatogenous retinal detachment (RRD). Biomicroscopy revealed an absence of the crystalline lens bilaterally, a single piece of integrated fibrotic membrane in the right eye, and a membrane with a central cleft at the level of the ciliary process in the left eye. A small amount of residual cortex was revealed in the peripheral part of the membranes bilaterally when the pupils were dilated. Funduscopic examination showed that the vitreous liquefied and retina detached bilaterally. The successful retinal reattachment by vitrectomy and the finding of a retinal tear proved that the RD was rhegmatogenous. This case investigates bilateral membranous cataract with bilateral RRD as a new syndrome, or whether RRD may be a new complication of membrane cataract.

Persistent diplopia following secondary intraocular lens placement in patients with sensory strabismus from uncorrected monocular aphakia

AIM

To evaluate the incidence of persistent diplopia after secondary posterior chamber intraocular lens (PCIOL) implantation in patients with prolonged uncorrected monocular aphakia with associated sensory strabismus.

METHODS

A retrospective institutional case series (1982 to 2005) of patients with sensory strabismus caused by uncorrected monocular aphakia from isolated ocular trauma who underwent secondary PCIOL implantation and subsequent successful strabismus surgery.

RESULTS

Following secondary PCIOL implantation, all 11 identified patients complained of new constant binocular diplopia. The mean period of uncorrected aphakia was 11 years (range 1 to 20; median and mode, 11). In seven patients diplopia could be eliminated before strabismus surgery, using loose prisms in free space or a haploscope, or both; these seven patients were diplopia-free following successful strabismus surgery (and showed suppression on Worth four-dot testing). In four patients diplopia could not be eliminated before strabismus surgery (either with loose prisms in free space or with a haploscope); these four patients had persistent diplopia despite successful strabismus surgery.

CONCLUSIONS

There is a significant risk of persistent diplopia in this setting. Inability to eliminate diplopia before strabismus surgery predicts persistent diplopia despite ocular realignment. Sensory testing should be done while the patient is still aphakic (with an aphakic contact lens) before consideration for secondary PCIOL implantation.

[Therapeutic effect of laser photocoagulation of ciliary processes in aphakic glaucoma]

OBJECTIVE

To evaluate the therapeutic effect of laser photocoagulation of ciliary processes after pars plana vitrectomy in aphakic glaucoma.

METHODS

Twenty patients (20 eyes) of aphakic glaucoma underwent vitrectomy plus laser treatment. During the surgery, after conventional 3-incision pars plana vitrectomy, a probe of semi-conductor diode laser (532 nm) was inserted through the sclera incision, the ciliary processes were then photocoagulated under direct visualization for 180 degree range. Before and after the surgery, the visual acuity, the intraocular pressure (IOP) as well as the outer appearance of the anterior segment were evaluated. The mean follow-up period was 13 months.

RESULTS

The IOP at the last visit was (21.35 +/-2.52) mmHg, which was significantly lower than that before the surgery [(39.75 +/-6.27) mmHg, P=0.000]. Atrophy of the ciliary processes was observed 1-3 months after the surgery.

CONCLUSION

Pars plana vitrectomy combined with laser coagulation of ciliary processes reduces the IOP in patients with aphakic glaucoma effectively.

Chronic 3,4-dihydroxyphenylalanine treatment induces dyskinesia in aphakia mice, a novel genetic model of Parkinson's disease

L-DOPA-induced dyskinesia (LID) is one of the main limitations of long term L-DOPA use in Parkinson's disease (PD) patients. We show that chronic L-DOPA treatment induces novel dyskinetic behaviors in aphakia mouse with selective nigrostriatal deficit mimicking PD. The stereotypical abnormal involuntary movements were induced by dopamine receptor agonists and attenuated by antidyskinetic agents. The development of LID was accompanied by preprodynorphin and preproenkephalin expression changes in the denervated dorsal striatum. Increased FosB-expression was also noted in the dorsal striatum. In addition, FosB expression was noted in the pedunculopontine nucleus and the zona incerta, structures previously not examined in the setting of LID. The aphakia mouse is a novel genetic model with behavioral and biochemical characteristics consistent with those of PD dyskinesia and provides a more consistent, convenient, and physiologic model than toxic lesion models to study the mechanism of LID and to test therapeutic approaches for LID.

Diabetic Vitrectomy

OBJECTIVE

To determine the effect of lens status upon the anatomic and visual results in primary diabetic vitrectomy.

DESIGN

Retrospective, comparative, consecutive case series.

PARTICIPANTS

One hundred two eyes of 85 patients with proliferative diabetic retinopathy and its complications that underwent primary vitrectomy.

METHODS

The eyes that remained phakic after vitrectomy were compared with the eyes that were either aphakic or pseudophakic (nonphakic) postoperatively.

MAIN OUTCOME MEASURES

Intraoperative and postoperative complications, vitreoretinal reoperation rate, and ultimate anatomic and visual success with at least 6 months' follow-up.

RESULTS

Preoperatively, 72 eyes were phakic, and 30 were aphakic (n = 1) or pseudophakic (n = 29). During vitrectomy, 1 eye underwent lensectomy and 12 eyes underwent phacoemulsification with lens implantation. Postoperatively, 59 eyes were phakic and 43 eyes were nonphakic. The vitreoretinal reoperation rate was significantly higher (P = 0.04) for the phakic group (28.8%) than for the nonphakic group (11.6%). Rubeosis iridis developed in 3 phakic eyes and no nonphakic eyes (P = 0.26). Intraoperative complications were similar in the phakic and nonphakic groups (P = 0.40). Postoperative complications such as rhegmatogenous retinal detachment (P = 0.39), nonclearing vitreous hemorrhage (P = 0.07), and anterior chamber complications (P = 0.60) were also similar. Visual acuity improved by at least 0.2 logarithm of the minimum angle of resolution units in 76.2% of the phakic eyes and 86.0% of the nonphakic eyes (P = 0.22).

CONCLUSIONS

Eyes that were phakic after primary diabetic vitrectomy had a significantly higher subsequent vitreoretinal reoperation rate when compared with nonphakic eyes, suggesting that diabetic eyes are less likely to require additional vitreoretinal surgery if they are rendered nonphakic before or during vitrectomy.

Anterior segment epibulbar choristoma containing brain tissue and with aphakia

We report an unusual case of an epibulbar choristoma in a neonate born with a mass arising from the cornea. Radiologic examination showed focal corneal bulge with absence of the lens. Histologic study revealed the lesion was an epibulbar choristoma composed of only brain tissue.

A proposed rapid methodology to assess the prevalence and causes of blindness and visual impairment

PURPOSE

To determine whether a sample of the 50-year-old and above population would provide comparable information to a total population-based survey.

METHODS

In 1996, a national eye survey of the total population in The Gambia was undertaken and the results concerning the prevalence and distribution of blindness and low vision have been reported. The same data set was used to analyse the prevalence and causes of blindness and low vision in people aged 50 years and above, and to compare the findings with the total population.

RESULTS

Of 55 bilaterally blind people in the total population, 83.6% were 50 years of age or older. The distribution by cause of blindness was similar for the total population and for those aged 50 years and above. Cataract and uncorrected aphakia accounted for 46% and 13%, respectively, in the total population and 48% and 15% in the 50 year and above age group. Trachoma accounted for 5% and 4%, and other corneal opacities for 16% and 13%, respectively. Phthisis bulbi, which may follow perforated corneal ulcers, ocular trauma/surgery or occasionally severe uveitis, accounted for 4% in both age groups, and glaucoma accounted for 9% in the total population and 11% in the 50 year plus group.

CONCLUSION

Assessment of the 50 year and above age group proved to be a good indicator for the causes of blindness and visual impairment in the total population and for determining those causes of blindness that are avoidable. Such an assessment requires a much smaller sample size, less than 20% of the sample size for the total population, and is likely to be less expensive.

Contact lens rehabilitation following repaired corneal perforations

BACKGROUND

Visual outcome following repair of post-traumatic corneal perforation may not be optimal due to presence of irregular keratometric astigmatism. We performed a study to evaluate and compare rigid gas permeable contact lens and spectacles in visual rehabilitation following perforating corneal injuries.

METHOD

Eyes that had undergone repair for corneal perforating injuries with or without lens aspiration were fitted rigid gas permeable contact lenses. The fitting pattern and the improvement in visual acuity by contact lens over spectacle correction were noted.

RESULTS

Forty eyes of 40 patients that had undergone surgical repair of posttraumatic corneal perforations were fitted rigid gas permeable contact lenses for visual rehabilitation. Twenty-four eyes (60%) required aphakic contact lenses. The best corrected visual acuity (BCVA) of > or = 6/18 in the snellen's acuity chart was seen in 10 (25%) eyes with spectacle correction and 37 (92.5%) eyes with the use of contact lens (p < 0.001). The best-corrected visual acuity with spectacles was 0.20 +/- 0.13 while the same with contact lens was 0.58 +/- 0.26. All the patients showed an improvement of > or = 2 lines over spectacles in the snellen's acuity chart with contact lens.

CONCLUSION

Rigid gas permeable contact lenses are better means of rehabilitation in eyes that have an irregular cornea due to scars caused by perforating corneal injuries.

Central corneal thickness and glaucoma in aphakic and pseudophakic children

BACKGROUND

The risk of glaucoma among aphakic children is as high as 32%, based primarily on intraocular pressure (IOP) measurements. Although IOP may be falsely elevated by increased central corneal thickness, central corneal thickness (CCT) values have not been reported in this population.

METHODS

Patients from the practices of 2 pediatric ophthalmologists and 2 glaucoma specialists had measurements of CCT, IOP, and optic nerve cupping, with visual field analysis when possible. Normal fellow eyes of unilateral aphakes and pseudophakes were included as controls.

RESULTS

In 36 aphakic and 6 pseudophakic eyes CCT averaged 660 microns compared with 576 microns for phakic fellow eyes (P < 0.0001). Glaucoma, defined by IOP at least 35 mm Hg or by IOP at least 22 mm Hg associated with optic nerve changes, occurred in 21% of 28 aphakic patients but in no pseudophakic patient.

CONCLUSIONS

CCT in aphakic/pseudophakic children is substantially increased compared with control patients. These values may be important in interpreting IOP measurements in these children.

Glaucoma in aphakia and pseudophakia in the Chennai Glaucoma Study

AIM

To determine the prevalence of glaucoma among aphakes and pseudophakes in a rural population of southern India.

METHODS

3924 subjects aged 40 years or above underwent complete ophthalmic examination. Glaucoma in aphakia/pseudophakia was diagnosed using International Society of Geographical and Epidemiological Ophthalmology criteria in aphakic/pseudophakic people.

RESULTS

54 subjects (37 aphakes, 17 pseudophakes) (1.38% of 3924 subjects, 11.2% of 482 aphakes/pseudophakes) had glaucoma in aphakia/pseudophakia. Aphakia, age, intraocular pressure (IOP), pseudoexfoliation, and peripheral anterior synechiae greater than or equal to 180 degrees of the angle were risk factors for glaucoma on univariate analysis. On multivariate analysis, IOP and aphakia were independent risk factors for glaucoma. 39 people (72.22%) with glaucoma had normal IOP at presentation. None of the people with glaucoma were aware of the disease. Blindness in one or both eyes was seen in 12 subjects (10 unilateral and two bilateral)-that is, 22.22% of people with glaucoma in aphakia/pseudophakia.

CONCLUSIONS

Glaucoma is an important cause of ocular morbidity among aphakes and pseudophakes in this rural population of south India. This glaucoma, responsible for unilateral or bilateral blindness in 22.2% of those affected, was entirely undetected in this study population.

[Risk factors of retinal redetachment after expected silicone oil removal]

PURPOSE

To analyze the clinical risk factors of the occurrence of retinal redetachment after expected silicone oil removal.

METHODS

Clinical data were studied retrospectively. A total of 105 eyes of 104 consecutive patients were enrolled according to the criteria as follows: the expected intraocular silicone oil removal was performed after pars plana vitrectomy for complicated rhegmatogenous retinal detachment (RRD); the retina was flat during silicone oil tampanade; the patients were dealt with by the same surgeon.

RESULTS

With a mean postoperative follow-up of 310 days, 11 of 105 eyes (10.4%) developed retinal redetachment after silicone oil removal. The redetachment rate was higher in the aphakic eyes (21.1%) than in the phakic/pseudophakic eyes (4.5%) (OR 5.69, P < 0.05). However, the factors, including giant tear, PVR grade C3 and D, previous failed retinal detachment surgery, high myopia, had no significance with retinal redetachment (Ps > 0.05). Among the 77 eyes undergoing prophylactic 360 degree laser retinopexy before silicone oil removal, 4 eyes had retinal redetachment (5.2%). The redetachment ratio was lower than those without prophylactic laser retinopexy (OR 0.16, P < 0.05).

CONCLUSION

Aphakia is a risk factor of retinal detachment after removal of silicone oil. Prophylactic 360 degree laser retinopexy can reduce the incidence of retinal redetachment.

Prevalence and causes of blindness in a tropical African population

A population based survey of Egbedore Local Government area (LGA), a tropical African population in Osun State, Nigeria was conducted to determine the prevalence and causes of blindness in the community, Osun State, one of the new states created on 27th August, 1991 is situated in the southwest region of Nigeria. It has a population of about 2, 654,244 using the population growth rate of 3.0 percent per year. Egbedore LGA has a population of 49,555 being the projected estimate of the local census done in 1991.

STUDY DESIGN

The study was in accordance with World Health Organisation recommendations. 3204 rural dwellers were examined. The survey team was divided into: 1. Registration team 2. Retrieval team 3. Visual acuity team 4. Ocular examination team. The survey candidates, once registered were asked to go to a nearby school or health center where visual acuity and ocular examination teams completed the assignment. The retrieval team consisted of an ophthalmic nurse and a local escort who persuaded and brought to examination site registered individuals who failed to appear voluntarily. Ocular examination team performed the eye examination. Analysis of data was done using personal computer AT model and systat package for analysis.

RESULT

It is found that 1.18% of the population was blind by WHO standard. Cataract alone accounted for 47.4% of the blind, uncorrected aphakia 18.4%, glaucoma 15.8%, phthisis bulbi 5.3%, uveitis, optic atrophy, macular degeneration, retinitis pigmentosa and refractive error all accounted for 2.6% each.

CONCLUSION

More than half of the burden of blindness is potentially curable. About a third is preventable through health education, early diagnosis and prompt treatment. A cataract outreach programme with provision of low cost aphakic glasses will go a long way in reducing blindness in this community and Osun State in general.

[Visual fields defects in cerebral hemorrhagic vascular accident]

Interpretation of the fields of vision forms a key part of ophthalmic and neurologic examinations. The homonymous hemianopa is a hallmark of a retrochiasmal lesion. Postchiasmal lesions that interrupt the visual pathway may have multiple causes which the circulatory disturbances is one of the most important. The authors present the case of a woman who has an isolated homonymous hemianopa produced by a vascular accident of occipital lobe, dwell upon the only manifestation of the cerebral acute hemorrhagic vascular accident was represented by an visual field defect.

[Cataract surgery in biphakia patients]

INTRODUCTION

Although the IOL implantation was used initially just for cataract surgery, in the last period IOLs are used in treating myopia more than -12D and hyperopia more than +4D, in phakic eyes, when the indications of excimer laser are limited.

OBSERVATION

We present the case of a 40 years old patient with the diagnosis: biphakia, complicated cataract and high myopia in both eyes. VA-RE = 2/50 cc, VA-LE = 3/50 cc, IOP-RE:15 mmHg, IOP-LE:16 mmHg. We performed, in two separate surgeries, the explantation of the intraocular lens, then the extraction of the opacified crystalline lens through the same incision and the implantation of an AcrySof foldable lens with an adequate power, in the bag. We discuss the causes of cataract formation in eyes with posterior chamber phakic intraocular lens, the choice of the IOL power, the incision for explantation and implantation, and the intraoperative technical difficulties.

CONCLUSIONS

The association of phakic IOLs and cataract represents a new challenge to the ophthalmic surgeon, taking into account that these IOLs are becoming more and more popular to correct high refractive errors.

Selective loss of dopaminergic neurons in the substantia nigra of Pitx3-deficient aphakia mice

Dopaminergic (DA) neurons in the ventral midbrain nuclei, substantia nigra pars compacta (SNc, A9) and ventral tegmental area (VTA, A10), play important roles in the control of movement, emotion, cognition, and reward related behavior. Although several transcription factors have been shown to be critical for midbrain DA neuron development, there has been no report of factor(s) that differentially regulate individual DA neuronal groups. Based on its highly restricted expression in the SNc and VTA in the brain, we hypothesize that the homeobox transcription factor Pitx3 may critically regulate the development of ventral midbrain DA neurons. In this study, we report that in Pitx3-deficient ak/ak mice, DA neurons in the SNc and the nigrostriatal pathway fail to develop properly, and DA levels are reduced to 10% of the wild type mice in the dorsal striatum. On the contrary, A10 neurons are intact in ak/ak mice and DA levels within their projection areas are not affected. This region-specific defect was already evident in newborn mice, suggesting that the defect had occurred during the early stages of mouse development. Taken together, our results indicate that Pitx3 is the first known transcription factor that may critically and selectively control proper development of A9 DA neurons and the nigrostriatal pathway. This observation is of great importance in understanding the mechanisms of DA neuron development and may also help us to understand the mechanism of selective degeneration of A9 DA neurons in Parkinson's disease and to devise novel therapeutic approaches for the disorder.

Effect of 3-piece AcrySof and downsized heparin-surface-modified poly(methyl methacrylate) intraocular lenses in infant rabbit eyes

PURPOSE

To evaluate after-cataract formation, ocular growth, and intraocular lens (IOL) behavior in lensectomized infant rabbit eyes implanted with a downsized heparin-surface-modified poly(methyl methacrylate) (HSM PMMA) IOL with long haptics or a 3-piece AcrySof(R) IOL (Alcon Laboratories, Inc.).

SETTING

St. Erik's Eye Hospital, Stockholm, Sweden.

METHODS

Clear lens extraction was performed in both eyes of 3-week-old rabbits. In Group 1 (n = 9), a downsized HSM PMMA IOL with long haptics was implanted in 1 eye and in Group 2 (n = 9), a 3-piece AcrySof IOL was implanted in 1 eye. The fellow eyes remained aphakic.

RESULTS

The amount of after-cataract was significantly less in the eyes with the IOLs than in the aphakic eyes. The eyes with the HSM PMMA IOL had significantly less after-cataract than those with the AcrySof IOL. No significant difference in axial length was noted between the IOL eyes and the aphakic eyes in either group. In the eyes with the 3-piece AcrySof IOL, there was anterior movement of the optic with occlusion of the pupil.

CONCLUSIONS

Eyes with the HSM PMMA IOL and the AcrySof IOL had less after-cataract than the aphakic eyes. The HSM PMMA IOL, however, inhibited after-cataract production significantly better than the AcrySof IOL. The 3-piece AcrySof IOL was seriously deformed in the infant rabbit eyes and caused occlusion of the pupil. Surgeons should be cautious in implanting this AcrySof IOL in the eyes of newborns or in eyes with severe microphthalmia.

Histopathologic ocular examination after lensectomy in a Macacus rhesus monkey, an unexpected event of secondary glaucoma

In a Macacus rhesus monkey an unilateral lensectomy was performed on the 15th day of life to study the emmetropization proces. During a period of 20.5 months refractional state, axial length, corneal dioptric power and intraocular pressure were measured in the aphakic and fellow eye. Results showed that axial elongation of the aphakic eye was larger in comparison to the phakic fellow eye. Histopathologic examination of the aphakic eye revealed glaucomatous changes due to obstruction in the anterior chamber angle.

Retrieval of a dropped corneal button from a vitrectomized eye

A successful retrieval of a dropped corneal button from an aphakic vitrectomized eye during penetrating keratoplasty is reported. A 52-year-old female patient underwent penetrating keratoplasty for aphakic corneal edema in a vitrectomized eye. The donor button inadvertently dropped into the vitreous cavity and was retrieved successfully. The dropped corneal button was visualized after focusing the operating microscope on the retina. The visualization significantly improved after aspiration of the fluid from the vitrectomized eye. The donor button was picked up by McPherson's forceps and subsequently sutured to the recipient's cornea. Corneal surgeons need to be aware of this rare complication in aphakic vitrectomized eyes and its retrieval after accurate visualization.

[Etiopathogenic consideration in the development of retinal detachment in aphakic and pseudoaphakic eye]

PURPOSE

Is to evaluate the risk factors implicated in the development of retinal detachment in aphakic and pseudophakic eyes.

MATERIAL AND METHOD

We studied 46 cases operated for cataract by planned extracapsular cataract extraction with or without intraocular lens, wich developed after the operation retinal detachments.

RESULTS

Retinal detachment appeared in 2.98% cases of EEC with AC-IOL and in 0.56% in EEC with PC-IOL. We performed Yag laser capsulotomy in 4 cases. Retinal detachment appeared in 12 cases between 6-12 months. The most frequent breaks causing retinal detachment where "horse shoe tears" in 23.4% of cases and tears in 14.89% cases.

CONCLUSIONS

1. High myopia and peripheral retinal degenerations are risk factors in the development of retinal detachment after the cataract operation. 2. Vitreous loss facilitates the appearing of vitreo-retinal tractions followed by retinal detachment. 3. PC-IOL reduces the frequency of retinal detachment by the stabilisation of the eye and limiting the ophthalmodonesis.

[Intraocular correction of aphakia after cataract extraction for uveitis in adolescents]

PURPOSE

To demonstrate 3 cases with pediatric pseudophakia after cataract extraction as a complication of unilateral uveitis.

MATERIAL AND METHODS

The boys were at the age of 8, 11 and 15 years at the moment of surgery. Uveitis was monocular, the etiology unknown and clinically significant cataract was diagnosed after several months from the beginning of inflammation. The last recurrence of uveitis was observed 1 to 6 months before operation. There were intermediate uveitis (2 cases) and anterior uveitis (1 cases). In 2 eyes PMMA implant was placed in-the-bag and in one eye in the ciliary sulcus. During surgery we did not observe any complications except greater tendency to bleeding. Follow-up after operation ranged from 1.5 to 2.5 years.

RESULTS

Visual acuity before cataract extraction was 0.01; 0.04 and 0.02 and during last visit after surgery it was 0.9, 0.6 and 0.4 respectively. Postoperative near distance visual acuity was 0.5, 0.75 and 1.25. We observed cystoid macular oedema in the latter case. Two months after PC-IOL implantation the symptoms of mild inflammation in the eye of 15-year-old boy with anterior uveitis occurred. Intraocular pressure before and after operation ranged from 12 to 17 mm Hg. Corneal central endothelial cell density was from 2850/mm2 to 3100/mm2 before and from 2469/mm2 to 2979/mm2 during last visit.

CONCLUSION

Cases of posterior pseudophakia during uveitis in children showing good functional and anatomical state of eyes in the long term observation after IOL implantation recommend the intraocular correction in carefully selected uveitic pediatric patients.

[Use of cyclophotocoagulation with diode laser in treatment of secondary glaucoma in children]

AIM OF THE PAPER

To evaluate the effectiveness of transscleral diode laser cyclophotocoagulation in treatment of secondary glaucoma in children.

MATERIAL AND METHODS

50 children (50 eyes) with secondary glaucoma (aphakic, posttraumatic, in Sturge-Weber syndrome and in aniridia) which was uncontrolled with medical and surgical therapy or the surgery had a high risk of postoperative complications. In all patients diode laser transscleral cyclophotocoagulation has been performed.

RESULTS

After one month intraocular pressure was reduced (with or without medical treatment) below 23 mm Hg in 40% of patients and after 6 months in 68% of patients. The worst results were observed in posttraumatic glaucoma.

CONCLUSION

Diode laser transscleral cyclophotocoagulation is a safe and effective method of secondary glaucoma therapy in children uncontrolled with other methods of medical and surgical therapy or when the surgery has a high risk of postoperative complications.

Management of post-traumatic aniridia with retinal detachment

PURPOSE

To reconstruct the anatomic and functional impairment in patients with post-traumatic aniridia, aphakia, and retinal detachment.

METHODS

Four patients with unilateral aniridia and aphakia as well as retinal detachment as results of severe eye injuries underwent scleral buckling, vitrectomy, membrane peeling, endolaser photocoagulation, silicone oil or gas temponade, combined with iris diaphragm-IOL implantation.

RESULTS

All four patients achieved successfully anatomic and functional reconstruction after surgery. During five to 22 months postoperative follow-up, all retinas remained attached. The final visual acuity increased from finger counting to 0.1-0.3.

CONCLUSIONS

The combination of vitreoretinal surgery and iris diaphrgm-IOL implantation is an effective method for post-traumatic aniridia, aphakia and traumatic retinal detachment. It could ameliorate photophobia and improve the biocular vision. Furthermore, artificial iris diaphragm implantation could prevent silicone oil-endothelia contact and salvage silicone keratopathy.

Primary vitrectomy for pseudophakic and aphakic retinal detachments

PURPOSE

To evaluate primary vitrectomy for the treatment of pseudophakic and aphakic retinal detachments. Primary vitrectomy may enable better identification of retinal breaks than scleral buckling procedures.

METHODS

A prospective study was performed of primary vitrectomy for the treatment of 25 consecutive cases of pseudophakic and aphakic retinal detachment.

RESULTS

The primary retinal reattachment rate was 84% (21 eyes). Surgical failure resulted from new/missed retinal breaks (2 eyes) and proliferative vitreoretinopathy (2 eyes). The final retinal reattachment rate with further surgery was 96% (24 eyes). There were 7 macula-on detachments which all retained their presenting visual acuity. A visual acuity of 6/18 or better was achieved by 56% of the 18 macula-off detachments. Visualisation of the peripheral retina was impaired in 17 eyes and procedures to improve visualisation were performed in 7 eyes. Retinal breaks were detected in 16 eyes at surgery that had not been identified pre-operatively. Raised intraocular pressure was the most common complication, affecting 10 eyes in the early post-operative period.

CONCLUSIONS

Primary vitrectomy offers certain advantages in the treatment of pseudophakic and aphakic retinal detachments. A controlled study is required to determine whether primary vitrectomy achieves a better outcome than scleral buckling procedures for these retinal detachments.

[Results of retinal detachment surgery in aphakic and pseudo-aphakic eyes]

PURPOSE

The authors present results of conventional treatment of a patient with the retinal detachment in the aphakic and pseudophakic eyes.

MATERIAL AND METHODS

The group consisted of 34 persons: 10 women and 24 men, aged from 40-79 years. Earlier the intracapsular (in 24 eyeballs) and extracapsular (in 3 eyeballs), lens extraction had been performed. The intraocular lens was inserted into 7 eyes. The following surgical technics were performed: cerclage in 16 eyes, screlar invagination in 5 eyes, scleral invagination with an extrascleral implant in 7 eyes, the extrascleral implant alone in 6 eyes.

RESULTS

Total retinal reattachment was attained in 85% in aphakic eyes and 100% in pseudophakic eyes.

[Sinusotrabeculectomy with regulated filtration in the treatment of secondary glaucoma]

A new method for surgical treatment of secondary glaucoma (neovascular, postuveal, traumatic, and aphakic) is described. The aims of the new method are as follows: regulation of ophthalmic tone in the postoperative period, pain relief, organ preservation, stabilization of the process, and creation of reliable routes of intraocular fluid discharge with formation of a stable diffuse functional pad. Seven patients (8 eyes) aged 13-70 years were operated on and followed up for up to 6 months. Preliminary results are presented. Positive shifts were observed in all cases.

Intermediate-term results of endoscopic diode laser cyclophotocoagulation for pediatric glaucoma

INTRODUCTION

Endoscopic diode laser cyclophotocoagulation (EDLC) is a new treatment modality for glaucoma. Experience with this surgical procedure in children is limited. We report our results after 3 years of follow-up and review the safety of this procedure in pediatric patients.

METHODS

EDLC was performed on 10 eyes of 8 children who had either aphakic glaucoma or refractory congenital glaucoma. Patients were treated in 2 groups. An initial group of 5 eyes with poor visual prognosis underwent a conservative treatment of no more than 180 degrees of ciliary processes. After an observational period, a second group of 5 eyes with better visual potential was treated more aggressively. Most eyes in the second group received cyclophotoablation to 270 degrees of ciliary processes. Patients were followed up until time of failure or for a minimum of 3 years.

RESULTS

At 3 years of follow-up, 50% of eyes that received a single treatment of endolaser had an intraocular pressure (IOP) of < or =22 mm Hg with or without glaucoma medications. Twenty percent had an IOP < or =22 mm Hg without any glaucoma medications. Five eyes were treated successfully with a mean IOP of 17.8 +/- 3.4 mm Hg at 36 months of follow-up. The remaining 5 eyes were considered treatment failures with postoperative IOPs >22 mm Hg, despite adjunctive glaucoma medications. Mean time to treatment failure was 10.5 months (range, 3.7-22.2 months). No sight-threatening complications occurred. None of the eyes became hypotonus or caused undue discomfort during the postoperative period.

CONCLUSION

EDLC is a relatively safe and effective procedure for the management of difficult pediatric glaucoma. Results are comparable to other cyclodestructive modalities. Although not observed in this study, it should be cautioned that phakic eyes might be at increased risk for surgical complications.

Long-term results after scleral buckling surgery in uncomplicated juvenile retinal detachment without proliferative vitreoretinopathy

PURPOSE

To evaluate long-term anatomic and functional results of scleral buckling surgery in retinal detachment without proliferative vitreoretinopathy in juvenile patients.

METHODS

A total of 33 eyes of 31 patients were operated on. Surgical techniques included segmental buckle (23 eyes), radial buckle (5 eyes), encircling band (4 eyes), and temporary balloon buckle (1 eye). The average age at time of surgery was 15.3 years and the average follow-up time was 8.9 years. Retinal detachment was associated with the following risk factors: myopia (14 eyes), blunt trauma (8 eyes), and aphakia (3 eyes). In 9 eyes, no risk factors were present. Fifteen eyes had a detached macula. In addition to anterior and posterior segment examination, binocular functions and ocular motility were evaluated.

RESULTS

Retinal reattachment required one operation in 29 eyes, two operations in three eyes, and three operations in one eye. In one eye, pars plana vitrectomy had to be performed to reattach the retina. At the end of follow-up, retinal reattachment was achieved in all eyes. Visual acuity of 20/40 or better was achieved by 39.4% preoperatively and 60.6% postoperatively; in 52.4%, binocular functions were normal.

CONCLUSION

Scleral buckling procedures allow favorable anatomic and functional results in juvenile retinal detachment without proliferative vitreoretinopathy.

Photorefractive Keratectomy For Hyperopia and Aphakia with a Scanning Spot Excimer Laser

OBJECTIVE

To study the safety, efficacy, predictability, and stability of photorefractive keratectomy (PRK) for hyperopia and aphakia.

METHODS

Fifteen eyes of 15 patients (mean age, 33 +/- 5.95 yrs) were enrolled in the study and divided into three groups. The first group was comprised of six eyes that had hyperopia ranging from +1.75 to +4.75 D; the second group had seven hyperopic eyes ranging from +5.00 to +9.75 D; the third group included two eyes of two aphakic patients. All eyes had PRK with a 193 nm argon fluoride excimer laser (Chiron-Technolas, Keracor 116) with a 10 Hz repetition rate and a fluence of 120 mJ/cm2. The total follow-up time in all eyes was 12 months.

RESULTS

In the lower hyperopia group, 0% eyes were within +/- 0.50 D and 66% (N = 4) of eyes were within +/- 1.00 D of emmetropia with the other two eyes between +1.00 and +2.00 D at 1 year after PRK. In the higher hyperopia group, all eyes had at least +3.00 D of hyperopia at 1 year. In the aphakic group, both eyes achieved less than 50% of the target correction of +10.00 D at 1 year. Final uncorrected visual acuity ranged from 20/20 to 20/30 in the lower hyperopia group, 20/30 to 20/50 in the higher hyperopia group, and count fingers in the aphakic group.

CONCLUSIONS

PRK is a relatively safe, stable, and effective procedure with reasonably good predictability for eyes with less than +5.00 D of baseline hyperopia, and poor predictability for eyes with more than +5.00 D of baseline hyperopia. PRK is ineffective in the correction of aphakia.

Scleral ectasia in rhegmatogenous retinal detachment

OBJECTIVE

To determine the relation between retinal tears and scleral ectasia.

DESIGN

Prospective study.

SETTING

University-based referral practice in Montreal.

PATIENTS

Fifty-seven consecutive patients with primary rhegmatogenous retinal detachments undergoing scleral buckling surgery. Patients with a history of trauma or previous cryotherapy, laser treatment or other vitreoretinal procedures were excluded. Fifteen patients with diabetes mellitus undergoing primary vitrectomy and prophylactic scleral buckling for nonclearing vitreous hemorrhage constituted the control group.

OUTCOME MEASURES

Presence of scleral ectasia, visual acuity, refractive error.

RESULTS

Thirty-one of the study patients were phakic and 26 were aphakic or pseudophakic. Fifteen (48.4%) of the phakic patients were found to have scleral ectasia, compared with six (23.1%) of the aphakic/pseudophakic patients and two (13.3%) of the control patients (p < 0.05, chi 2 test). The most frequent location of ectasia was the superotemporal quadrant. Retinal tears occurred in the same quadrant as scleral ectasia in 12 (80.0%) of the phakic patients.

CONCLUSIONS

Scleral ectasia may be causally related to rhegmatogenous retinal detachment in certain cases.

[Laser capsulotomy in cases of posterior capsule opacity in pseudophakia, aphakia and traumatic cataracts]

The results of Nd:YAG laser capsulotomy performed in 94 eyes of 90 patients (48 males and 42 females) are presented. Visual acuity 0.5 and better was achieved in 58.4% of cases. The authors discussed the techniques of the operations and some possible complications.

Retinal detachment after cataract surgery. Surgical results

The authors studied the results obtained by the Retina Associates in 376 eyes of 361 patients operated on for retinal detachment associated with aphakia or pseudophakia with a postoperative follow-up of at least 6 months. All eyes underwent scleral buckling. The series included 103 eyes with aphakia, 17 eyes with iris-fixated intraocular lens, 111 eyes with anterior chamber (AC) IOL, and 145 eyes with posterior chamber (PC) IOL. The overall success rate for retinal detachment was 93%, without significant difference among the different groups. The aphakia and PC IOL groups had significantly higher prevalence (63% and 60%, respectively) of visual acuity equal to or better than 20/40 compared with the AC IOL group (33%). The prevalence of postoperative corneal edema in the AC IOL group was significantly higher than in the aphakia and PC IOL groups. Preoperative vitreous hemorrhage, large retinal breaks, posterior retinal breaks, total retinal detachment, proliferative vitreoretinopathy, and the need for performing a closed vitrectomy were significant factors in predicting ultimate failure.

Retinal detachment after cataract surgery. Predisposing factors

The authors studied the characteristics of 376 eyes of 361 patients with primary retinal detachment (RD) and surgical aphakia (103 eyes) or pseudophakia (273 eyes). Of the pseudophakic eyes, 17 had an iris-fixated intraocular lens (IOL), 111 had an anterior chamber (AC) IOL, and 145 had a posterior chamber (PC) IOL. Of the PC IOL cases, 48 (33%) had undergone YAG capsulotomy, and 46% of them developed RD within 6 months after capsulotomy. The frequency of no breaks found in pseudophakic RD (15%) was significantly higher than in RD with simple aphakia (5%). The most frequent reasons were incomplete fundus view due to a small pupil in the iris-fixated (83%) and the AC (44%) groups, and cloudiness of capsular remnants in the PC group (78%). In pseudophakic RD, sizable single tears, located more posteriorly than in RD with simple aphakia, were frequent. The authors speculate that in pseudophakic RD the retinal breaks may resemble those noted in phakic RD.

Trabeculodialysis for inflammatory glaucoma: a review of 25 cases

We reviewed the results following trabeculodialysis in 25 eyes of 22 patients with secondary glaucoma due to chronic anterior uveitis. After 1 year, intraocular pressure (IOP) was uncontrolled (greater than 21 mm Hg) in 11 eyes (44%). Trabeculodialysis controlled IOP (less than 21 mm Hg) in 14 eyes (56%), with an average follow up of 52 months (range, 12 to 151 months). Sixteen eyes (64%) were aphakic, but did no worse than the phakic eyes. One eye developed a subchoroidal hemorrhage 3 days postoperatively which required drainage. No other serious complications were encountered. Trabeculodialysis is a safe procedure which can achieve pressure control in these difficult eyes.

The glaucomas in aphakia and pseudophakia

Intraocular pressure may become temporarily or permanently elevated at various intervals following cataract surgery. There are several mechanisms by which glaucoma develops as a complication of the cataract extraction itself. The presence of a pseudophakos may or may not contribute to the pathogenesis. Important diagnostic clues include the anterior chamber depth, the presence or absence of an iridectomy, gonioscopic findings, and the appearance of the optic nerve head. Life-long medical treatment is frequently justified, as alternative laser or surgical modalities may not be successful. The exact causes for high failure of filtration surgery in aphakic eyes is not clearly understood; scarring of the conjunctiva, the vitreous, and altered characteristics of the aqueous humor have all been incriminated. Current research to improve surgical success includes the development of effective artificial drainage implants or the use of pharmacologic modulators of wound healing, which promote filtration by preventing scar formation.

Binocular diplopia in unilateral aphakia: the role of botulinum toxin

We have treated 12 unilaterally aphakic patients, with a manifest squint and binocular diplopia, with botulinum toxin injection to the appropriate horizontal rectus muscle, in an attempt to reduce the angle of squint and thereby resolve the diplopia. In all cases a short-term reduction in the angle of squint was achieved. In nine patients, whose aphakia was corrected with a contact lens, and eight of whom had had their lenses removed because of trauma, this reduction was only temporary. In three patients, however, who had had a non-traumatic cataract removed, replaced with a posterior chamber implant, control of the deviation was maintained long after the acute effect of the toxin had disappeared, with the development of coarse binocular single vision, a fusion range, and abolition of all diplopia. The possible reasons for these different responses are discussed and it is suggested that in cases of binocular diplopia following lens extraction, botulinum toxin treatment should be considered prior to any extraocular muscle surgery, as temporary reduction of the deviation may be sufficient to allow recovery of binocular single vision.

Intraocular pressure response to the replacement of pilocarpine or carbachol with echothiophate

In 20 patients with open-angle glaucoma in aphakia or pseudophakia whose intraocular pressure had remained uncontrolled on their current medical therapy, the medication was changed from pilocarpine or carbachol to echothiophate iodide. In all, 12 patients (60%) showed a statistically significant improvement in pressure control, 7 (35%) showed no change, and 1 had higher pressure. One-third of the patients with improved intraocular-pressure control eventually required laser or incisional surgery after a mean of 23 months, whereas the remaining subjects were controlled for the duration of the follow-up, which averaged 26 months. Side effects encountered during echothiophate iodide treatment included ocular irritation, decreased vision, and one retinal detachment.

Corneal ulcer and adverse reaction rates in premarket contact lens studies

We analyzed clinical data on 22,739 contact lens wearers who were studied and whose lenses were approved under 48 manufacturer-sponsored studies for the Food and Drug Administration between 1980 and 1988. The incidence of corneal ulcers was low in the cosmetic (nontherapeutic) daily-wear soft and rigid gas-permeable lens wearers (1/1,923 and 1/1,471 patient-years, respectively). Corneal ulcers and severe adverse reactions occurred two to four times more frequently in extended-wear cosmetic soft and rigid gas-permeable lens wearers than in cosmetic daily-wear lens wearers. Aphakic extended-wear soft lens users were nine times more likely to develop a corneal ulcer when compared to the soft daily-wear cosmetic group. Corneal abrasions and keratitis accounted for 81 of 159 severe adverse reactions, whereas corneal ulcers accounted for 28 of 159 adverse reactions. The data indicate that overnight extended wear of contact lenses is associated with a greater risk of serious, sight-threatening complications than daily wear.

[Secondary glaucoma after silicone oil surgery]

In spite of advances in surgical technique and the development of purified silicone oils, secondary glaucoma still develops in 10-20% of cases following silicone oil surgery. In the first part of this study it is shown by life-table analysis that factors such as early lens removal, inferior iridectomy, early silicone removal or the use of purified silicone oil have little or no influence on the development of glaucoma. In the second part an attempt is made to pinpoint possible causes of secondary glaucoma by re-examining all cases in which elevated intraocular pressure developed some time after silicone oil surgery. It was found that a multitude of factors (e.g., inflammation, angle-block, anterior peripheral synechiae and emulsification) were involved in the pathogenesis of temporary or persistent secondary glaucomas. In most cases pre-existing pathology was found to be responsible rather than the silicone oil itself. The majority of the cases in which the silicone oil caused secondary glaucoma by emulsification responded well to medication alone or removal of the silicone oil.

Retinal injury induced by near-ultraviolet radiation in aphakic and pseudophakic monkey eyes. A preliminary report

The effect of repeated exposures to low-intensity, near-ultraviolet (UV) radiation on the retinas of phakic, aphakic, and pseudophakic monkey eyes was studied. Ten eyes (4 aphakic eyes, 3 pseudophakic eyes, and 3 normal phakic eyes) of five rhesus monkeys were used. The near-UV radiation was generated by a high-pressure mercury vapor lamp with a total radiance of 14.43 mW/cm2/sr. Exposure regimens were 5 minutes a day for 10 days, 15 minutes a day for 5 days, or 60 minutes a day for 5 days. The retinas of aphakic and pseudophakic eyes were exposed to a daily dose of more than 0.97 J/cm2, or a total dose of more than 4.9 J/cm2 in 5 days at a retinal irradiance of more than 1.0 mW/cm2. Three of four aphakic eyes and one of three pseudophakic eyes showed clinical and pathologic retinal lesions after radiation. None of the three phakic eyes was damaged. The retinal lesions showed mild opalescent thickening ophthalmoscopically and retinal pigment epithelial staining by fluorescein angiography. Histopathologically, the retinal pigment epithelium was the site of primary injury by near-UV radiation.