The indications and outcome of paediatric corneal transplantation in New Zealand: 1991-2003

AIM

To evaluate patient characteristics, indications, surgical details, and outcome of paediatric keratoplasty in New Zealand.

METHODS

As part of a prospective longitudinal study, paediatric keratoplasty data collected by the New Zealand National Eye Bank (NZNEB) was analysed for the 13 year period 1991-2003.

RESULTS

During the study period the NZNEB supplied 2547 corneas for keratoplasty, of which 65 (3%) were used for paediatric patients (14 years or younger). The 65 keratoplasties were performed in 58 eyes of 52 patients (66% male, 34% female, mean age 10.6 years, SD 4.3 years). Indications were classified into three groups: congenital (16%, n = 9), acquired non-traumatic (74%, n = 43), and acquired traumatic (10%, n = 6). Peters' anomaly (7% of total), keratoconus (67%), and penetrating trauma (8%) were the most common indications in each group, respectively. 82% of keratoplasties with known outcome survived (clear graft) 1 year postoperatively, 16% failed, and one patient died. Keratoplasty for congenital indications had a lower 1 year survival rate (78%) compared to acquired non-traumatic (85%) and traumatic (100%) indications, although the difference was not statistically significant (p = 0.65). 38% of patients with known outcome had a 1 year postoperative best corrected Snellen visual acuity (BCSVA) of 6/9 or better, and 60% had a BCSVA of 6/18 or better. Visual outcome was significantly better for acquired compared to congenital indications (p = 0.03).

CONCLUSION

Analysis of the NZNEB database provided valuable information in relation to paediatric keratoplasty in New Zealand. In particular, this study highlighted an unusually high prevalence of keratoconus as an indication for keratoplasty. In addition, a high 1 year survival rate and good visual outcome were identified, especially in cases of keratoplasty for acquired conditions.

Relationship between retinopathy and cirrhosis

AIM: To evaluate ophthalmic disorders with special attention to retinopathy in cirrhotic patients. Vitamin A deficiency-related ophthalmopathy, xerophthalmia, and color blindness may be documented in cirrhosis due to various etiologies. Retinopathy is an obscure feature of cirrhosis.

METHODS: Thirty-two cirrhotic patients, who were followed up by Clinics of Gastroenterology, Izmir Ataturk Teaching and Research Hospital, were enrolled to the study. Associated systemic diseases such as diabetes mellitus and hypertension were excluded. Thirty-two healthy volunteers took part as the control subjects. All participants had ophthalmologic examination in the same hospital.

RESULTS: Five (15.6%) of the cirrhotic subjects had soft exudate in the retina. None of the control subjects had retinopathy (P<0.05). Intraocular pressure (IOP) measured for both eyes were also significantly lower in the cirrhotics (P<0.05 vs P = 0.01). There were no statistically significant differences between the two groups in terms of other ophthalmic pathologies. The ophthalmic findings did not show up any differences according to the etiology of cirrhosis.

CONCLUSION: Soft exudates may develop in cirrhotic patients probably due to loss of synthetic function of liver and hemodynamic effects of portal hypertension. Retinopathy must be sought in cirrhosis because of its severe morbidity.

Forty Years of Changing Indications in Penetrating Keratoplasty in Israel

PURPOSE

To examine the leading indications for keratoplasty and identify the changing trends in the past 40 years in Israel.

METHODS

Pathology reports of all penetrating keratoplasties (PKPs) performed at Hadassah-Hebrew University Hospital from 1961 to 2000 were reviewed. We evaluated the indications for keratoplasty in each decade between the years 1961 and 2000.

RESULTS

During the 40-year period, a total of 1681 PKPs were performed. Keratoconus (n = 478, 28.4%) was the most common indication, followed by graft failure (n = 226, 13.4%), pseudophakic corneal edema (PCE) (n = 142, 8.4%), herpetic infections (n = 125, 7.4%), nonherpetic infections (n = 114, 6.8%), scarring (n = 113, 6.7%), and trauma (n = 110, 6.5%). The 7 groups account for approximately 77.5% of all keratoplasties performed. Ocular infections were the most common indications before 1970 and have been declining ever since. Keratoconus became the leading indication in the past 30 years. In the past decade, of 663 keratoplasties, keratoconus was the most common indication (56, 38.6%) followed by graft failures/rejections and PCE (the second most common indication between the years 1981 and 1990).

CONCLUSIONS

Keratoconus was the leading indication for keratoplasty in our series. There was a decreasing trend in PK for ocular herpetic infections during the decades. The rate of PCE decreased while failed graft became the second most common indication for PKP during the past decade.

[Indications for keratoplasty in District Railway Hospital in Katowice]

PURPOSE

The retrospective analysis of indications for keratoplasty.

MATERIAL AND METHODS

The study of 517 keratoplasties between May 2000 and December 2004.

RESULTS

The indications were: corneal oedema--24,5%, keratoconus--18,1%, corneal leucoma--15,0%, limbus insufficiency--10,2%, Fuchs endothelial dystrophy--9,0%, graft decompensation--8,1%, other acquired keratopaties--5,9%, corneal perforation--5,8%, anterior and stromal dystrophies--2,3%, Peters' syndrome--0,38%, choristoma--0,19%.

CONCLUSION

Main indication for keratoplasty are corneal oedema and keratoconus.

Triptans and the Incidence of Epithelial Defects During Laser in situ Keratomileusis

PURPOSE

To investigate whether the incidence of epithelial defects during laser in situ keratomileusis (LASIK) was different in patients who were taking sumatriptan (Imitrex, Glaxo Smith Kline, Pittsburgh, Pa) for migraine headaches than in those who were not.

METHODS

A retrospective chart review was performed on 54 eyes of 28 patients who had been identified as taking sumatriptan and had undergone LASIK at Minnesota Eye Consultants between 1999 and 2001. These patients were compared with 54 gender- and age-matched control eyes operated on with the same microkeratome at the same location during the same period of time. The incidence of epithelial defects during LASIK was compared between the two groups.

RESULTS

In the sumatriptan group, 11.1% (6 of 54) of eyes developed epithelial defects as compared to 9.3% (5 of 54) of eyes in the non-triptan group (P=.75, chi square). More recent sumatriptan exposure did not increase the incidence of epithelial defect (P=.47). In patients in whom sumatriptan was stopped >1 month prior to LASIK, 6.3% (1 of 16 eyes) had epithelial defects; in patients in whom sumatriptan was stopped <1 month prior to LASIK, 14.3% (4 of 28 eyes) developed epithelial defects; and 9.3% (5 of 54 eyes) of patients in whom no triptans had ever been used had epithelial defects (P=.70).

CONCLUSIONS

There is no correlation between the use of sumatriptan for relief of migraine headaches and the generation of epithelial defects during LASIK. There appears to be no reason to stop triptans before proceeding with LASIK.

[Prevalence of Kayser-Fleischer ring in patients with Wilson's disease]

The aim of the study was to assess prevalence of Kayser-Fleischer ring in children with Wilson's disease. 36 patients aged 7-17 years were enrolled into the study. All of them underwent ophthalmic examination by slit-lamp biomicroscopy. Kayser-Fleischer ring was found in 2 children (5.6%)--16 years old boy and girl with liver insufficiency. In addition, the girl had neurological symptoms. After 2 years of treatment K-F ring was not detected in the girl's eyes. Our data indicate that Kayser-Fleischer ring is rare in children and its absence does not exclude diagnosis of Wilson's disease.

Cytologic findings, and feline herpesvirus DNA and Chlamydophila felis antigen detection rates in normal cats and cats with conjunctival and corneal lesions

Samples were collected from 36 cats with feline herpesvirus (FHV-1)-related ocular disease (conjunctivitis, epithelial or stromal keratitis, or corneal sequestration), and 17 cats without ocular changes. Corneoconjunctival swabs, scrapings and biopsies were tested in various combinations for presence of FHV-1 DNA using single round (sr) polymerase chain reaction (PCR) and nested PCR (nPCR). Additional swabs from the inferior conjunctival fornix were tested by enzyme-linked immunosorbent assay for Chlamydophila felis antigen. Cytologic evaluation was carried out on conjunctival (cats with conjunctivitis) and corneal (cats with keratitis) cytobrush preparations. FHV-1 DNA was detected by PCR in 14 (39%) cats with ocular disease and 1 (6%) of the control group. Agreement between srPCR and nPCR results was significant (P < 0.01). FHV-1 DNA was detected in 3/7 cats with conjunctivitis, 5/6 cats with epithelial keratitis, 3/11 cats with stromal keratitis, and 3/12 cats with corneal sequestration. There was a significant association (P = 0.0027) between viral presence and epithelial keratitis. However, no significant association was found between viral presence and conjunctivitis (P = 0.059), stromal keratitis (P = 0.15), or corneal sequestration (P = 0.18). With respect to FHV-1 DNA detection, intersample agreement was significant (P < 0.03). No sampling technique seemed more likely than another to harvest detectable viral DNA, except for cats with corneal sequestrum in which viral DNA was not detected using corneoconjunctival swabs. FHV-1 DNA was detected in 6/9 samples with intranuclear inclusion bodies and in 6/7 cats with eosinophils on cytologic examination. All samples tested negative for C. felis antigen.

Risk factors for failure of simultaneous penetrating keratoplasty and cataract extraction

OBJECTIVE

To evaluate the indications, complications, and outcomes of simultaneous cataract extraction and penetrating keratoplasty (PKP) and the risk factors for failure of the procedure.

SETTING

Tertiary referral medical center.

METHODS

In a retrospective noncomparative interventional case series, the charts of 66 consecutive patients (70 eyes) who had simultaneous PKP and cataract extraction using the same surgical technique were reviewed.

RESULTS

The mean follow-up was 32.4 months (range 6 to 125 months). The primary corneal graft remained clear in 48 eyes (69%) and failed in 22 eyes (31%). Sixteen eyes with a failed graft (73%) had 1 or 2 repeat keratoplasties; 8 (50%) were successful. At the end of follow-up, 56 eyes (80%) had a clear corneal graft. Nine eyes (41%) with a failed primary graft and 2 eyes (4%) with a clear primary graft had intracapsular cataract extraction (P<.001); 13 eyes (59%) and 46 eyes (96%), respectively, had extracapsular cataract extraction (P<.001). All eyes with a failed primary graft and 18 eyes (37%) with a clear primary graft had postoperative complications (P<.001). Eyes with a failed graft had more postoperative surgical interventions (P<.001). There were no statistical differences between eyes with clear grafts and eyes with failed grafts in sex, age, indications for surgery, corneal graft diameter, intraoperative vitreous loss, and intraocular lens placement.

CONCLUSIONS

Intracapsular cataract extraction, postoperative complications, and postoperative surgical interventions may increase the risk for graft failure in simultaneous cataract extraction and PKP. Intraocular lens implantation did not increase the risk for graft failure.

Changing indications for corneal transplantation at the King Khaled Eye Specialist Hospital (1983-2002)

PURPOSE

To identify changing indications for keratoplasty over the last 20 years at a tertiary care eye hospital in a country with rapidly evolving ophthalmic care services.

METHODS

A retrospective review was performed of the eye bank records of every patient who received a lamellar or penetrating keratoplasty at the King Khaled Eye Specialist Hospital in Riyadh, Saudi Arabia, between January 1, 1983 and December 31, 2002. For each case, the primary surgical indication was identified.

RESULTS

A total of 8318 corneal transplants were performed during this 20-year period. In the first 5 years of the study, the leading indications for corneal transplantation were corneal scarring (52.0%), aphakic/pseudophakic bullous keratopathy (13.5%), corneal degeneration (10.0%), and keratoconus (7.6%). During the last 5 years of the study, the leading indications for corneal transplantation were keratoconus (40.2%), corneal scarring (19.8%), failed corneal transplant (11.3%), and corneal ulceration (10.2%). There was a dramatic increase in the number of transplants performed for keratoconus (441%) and failed corneal transplants (285%) as well as a dramatic decrease in the number of transplants performed for corneal degeneration (-88%) and scarring (-60%) between the first and last 5 years of the study period.

CONCLUSIONS

Major changes in the indications for corneal transplantation were related to the introduction and expansion of modern ophthalmic services at a time of rapid socioeconomic development and population growth.

Feline corneal sequestra: a review of 64 cases (80 eyes) from 1993 to 2000

Feline corneal sequestrum is a common condition of the feline cornea. The purpose of this study was to provide a detailed description of the clinical features of the condition including the response to different management options and to assess the rate of recurrence. The medical records of 64 cases (80 eyes) of feline corneal sequestra that presented to the Animal Health Trust from 1993 to 2000 were reviewed. Fifty-two cases were reviewed retrospectively; 12 cases were assessed prospectively between April and September 2000 as part of a separate study. The Persian was the most frequently encountered breed and the mean age of affected cats was 5.6 years. At initial presentation, sequestra were unilateral in 58 cats and bilateral in 6 cats, 5 of which were Persians. Ocular discomfort and ocular discharge were common presenting signs, occurring in 42 and 36 eyes, respectively. Seventy-four eyes were managed surgically with keratectomy only (n = 44) or keratectomy followed by a graft procedure (n = 30). Sequestra recurred in 16 eyes in the study. There was no significant difference in the rate of recurrence between eyes that received a graft procedure (n = 5) and eyes that did not (n = 11) (P = 0.56). Complications following transection of conjunctival pedicle grafts were observed. Brown to black discoloration of noncorneal tissue and therapeutic biomaterials was observed, including discoloration of both viable and apparently nonviable grafted conjunctival tissue, small intestinal submucosa graft material and bandage contact lenses.

Eye involvement in inherited epidermolysis bullosa: experience of the National Epidermolysis Bullosa Registry

PURPOSE

To determine the frequency of ocular manifestations in inherited epidermolysis bullosa (EB) within the continental United States and to define the estimated cumulative risks of developing nonscarring (blisters or erosions) and scarring corneal manifestations within each major EB subtype over time.

DESIGN

Observational (cross-sectional and longitudinal).

METHODS

Up to 16 years of longitudinal follow-up was conducted on 3,280 consecutively enrolled patients in the National EB Registry, an epidemiologic study funded by the National Institutes of Health. Data were stratified by major EB type and subtype. Frequencies of occurrence were determined for eight variables (corneal erosions or blistering; corneal scarring; symblepharons; blepharitis; ectropions; lacrimal duct obstruction; impaired vision; blindness) by contingency tables, and cumulative risks were generated by life table analysis technique.

RESULTS

The most common ocular manifestations were corneal erosions and blisters. Frequencies mirrored relative severity of skin disease, with 74.10% of all patients with recessive dystrophic EB, Hallopeau-Siemens (RDEB-HS) and 47.50% of all patients with junctional EB, Herlitz (JEB-H) experiencing at least one episode. Lower frequencies were noted for corneal scarring. Symblepharons and ectropions were most commonly seen in inversa RDEB and JEB-H, respectively. Blindness was reported in 6.47% of RDEB-HS patients. The cumulative risks of nonscarring and scarring corneal lesions in JEB-H at age 5 are 83.18% and 27.08% and at age 25 are 83.18% and 72.22%. With time, the cumulative risk of each in RDEB-HS approached that reported in JEB-H patients.

CONCLUSION

Ocular disease activity, particularly corneal, is common in some EB subtypes. Careful ophthalmologic examination should become an integral part of the management of all patients with inherited EB.

Penetrating Keratoplasty in Nepal

PURPOSE

To identify indications and outcomes in a large series of penetrating keratoplasty surgeries performed in Nepal.

METHODS

A retrospective case series of 472 consecutive penetrating keratoplasty surgeries (408 patients) performed at Tilganga Eye Center, Kathmandu, Nepal from June 1994 to September 1999.

RESULTS

Mean recipient age was 39.2 years (+/- 19.7 years). Main indications for PKP were corneal scar (37%), adherent leukoma (35%), perforation or impending perforation (9%), pseudophakic bullous keratopathy (6%), keratoconus (4%), and aphakic bullous keratopathy (3%). Mean duration of follow-up was 27.6 +/- 25.1 months. Sixty-five percent of available grafts were clear at 6 months, and 70% of available grafts were clear at 3 years. Six months postoperatively, 15% of patients had acuity better than 6/18, 37% had acuity between 6/18 and 6/60, and 17.7% had acuity between 6/60 and 3/60. Common causes of graft failure were endothelial failure (43%), increased intraocular pressure (15%), ulcer (14%), and trauma (7%).

CONCLUSIONS

The corneal diseases and indications for transplant surgery in Nepal are different from those in the Western world. Despite these differences, penetrating keratoplasty is a successful and reasonable way to reduce corneal blindness in developing nations.

An Epidemiological and Clinical Study of Ocular Manifestations of CongenitalRubella Syndrome in Omani Children

OBJECTIVE

To conduct a follow-up study in patients with congenital rubella syndrome (CRS) in Oman and analyze the prevalence of ophthalmic disorders and associated systemic problems.

METHODS

This historical prospective cohort study included review of 32 surviving patients with CRS reported by the surveillance system in Oman from 1987 through 2002. All patients underwent a complete ophthalmic examination that included visual acuity estimation, refraction and anterior and posterior segment evaluation, and intraocular pressure measurement. Pediatric and otorhinolaryngologic consultations were also performed.

RESULTS

The age-adjusted prevalence of CRS in Oman was 73.2 per million in the Omani population younger than 20 years, and the incidence was 0.6 per 1000 live births. Cataract, retinitis, microphthalmos, and glaucoma were observed in 11, 16, 6, and 4 patients, respectively. Keratoconus, corneal hydrops, and spontaneous resorption of lens were found in 1 patient each. Vision testing was possible in 16 children; 4 were bilaterally blind. Patients who had undergone eye surgery had significantly lower visual acuity, as compared with those who had not undergone surgery (relative risk 2.53; 95% confidence interval, 1.07-6.13). Among the 11 patients with CRS with cataract, we found hearing loss, cardiac anomalies, and neuropsychologic anomalies in 7, 4, and 6 children, respectively.

CONCLUSIONS

Congenital rubella syndrome has a wide variety of severe ophthalmic and systemic complications. High clinical vigilance for signs of CRS and regular observation of surviving patients with CRS is desirable. In patients with cataract, the functional results of surgery, despite state-of-the-art ophthalmic care, continue to be poor. Because of a high prevalence of visual, audiologic, and neurologic disabilities, surviving patients with CRS pose a burden on the medical and social communities. Emphasis in management ought to be prevention of CRS through effective immunization programs.

Corneal toxicity: the epithelium and stroma in iatrogenic and factitious disease

Corneal toxicity is caused by chemical trauma and by iatrogenic and factitious disease, which are often overlooked, and which are reviewed here. The clinical signs of iatrogenic disease are usually nonspecific and identical to those resulting from other causes of surface disease. Factitious disease is either the result of mechanical trauma or the abuse of toxic eye drops. One epidemiological study, in a tertiary setting, identified 13% of keratoconjunctivitis cases as iatrogenic. Healing was prolonged taking 7-93 (median 28.5) days. Pathogenic mechanisms vary widely with different drugs and include subclinical scarring, pseudopemphigoid, drug-induced ocular cicatricial pemphigoid, and toxic follicular reactions. There is little readily available data either on the probability of the development of adverse reactions or for the comparison of different drugs. The assessment of the toxicity of topical drugs is currently by the Draize test in rabbits. New in vitro tests on human corneal epithelial cell cultures include ATP assays for cell viability, scanning EM of epithelial microvilli, and vital staining to assess cell membrane permeability and intracellular esterase. Despite their simplicity, these test systems can correlate well with clinical toxicity and provide a toxicity index for drug comparisons. Treatment requires drug withdrawal or substitution by non-preserved and less toxic preparations. Factitious injury is rare, difficult to diagnose, and should only be considered when all other diagnoses have been excluded. Prevention requires a high level of awareness of the potential for iatrogenic disease, particularly in the high-risk setting of chronic ocular surface disease.

The prevalence of ocular signs in acne rosacea: comparing patients from ophthalmology and dermatology clinics

PURPOSE

To describe and compare the ocular signs in patients diagnosed with acne rosacea by the ophthalmologist with the ocular signs in the patients diagnosed with rosacea by the dermatologist.

METHODS

We reviewed the medical records of 176 randomly selected patients diagnosed with rosacea at the University of California, Davis, Medical Center: 88 patients each from the Department of Dermatology and the Department of Ophthalmology. Of the 88 patients diagnosed with acne rosacea by a dermatologist, 22 (25%) had an ophthalmologic evaluation done prior to the study. In those patients without an ophthalmologic assessment, ocular complaints noted by the dermatologist were recorded. We recorded ocular signs including lid, conjunctival, corneal, episcleral, and scleral manifestations as well as charted observations of the iris, lens, intraocular pressures (IOPs), best corrected visual acuity (VA), and funduscopic examination. Age and sex were recorded from the initial ophthalmologic evaluation. The analysis was designed to compare the prevalence of signs and symptoms in two clinical settings.

RESULTS

The prevalence of documented meibomian gland dysfunction (p < 0.001), telangiectasia (p = 0.004), and anterior blepharitis (p = 0.008) was significantly higher in ophthalmology patients when compared with dermatology patients. Of the conjunctival signs evaluated, only the presence of interpalpebral conjunctival hyperemia (p = 0.005) was found to be significantly higher in ophthalmology patients. The corneal, episcleral, scleral, and lens findings did not demonstrate a statistically significant difference between groups.

CONCLUSION

The major and most easily observable ocular problems in rosacea patients presenting either to ophthalmology or dermatology are lid disease-related manifestations. As might be expected, eye signs and symptoms are more commonly noted in the eye clinic. A clinician's increased awareness of the common ocular findings of rosacea, however, may aid in earlier diagnosis and treatment of ocular rosacea.

Risk factors for ocular surface disorders in patients with diabetes mellitus

OBJECTIVE

To evaluate risk factors for ocular surface disorders and tear dysfunction in patients with type 2 diabetes.

STUDY DESIGN AND METHODS

This prospective case controlled study included 41 patients with type 2 diabetes and 20 healthy subjects as the control group. All subjects underwent routine ophthalmic examination, tear film break-up time (BUT) test, Schirmer test, fluorescein dye test, rose bengal staining test, and a questionnaire for subjective complaints. The relationship of metabolic control of diabetes mellitus, duration of diabetes, severity of diabetic retinopathy, and argon laser photocoagulation (ALP) to tear dysfunction was evaluated.

RESULTS

Tear film BUT and Schirmer test values were significantly lower in diabetic patients compared with control subjects (P < 0.001). In the diabetic group, significantly more subjects had abnormal fluorescein and rose bengal staining than in the control group (P < 0.001). Abnormal tear function tests were associated with poorer metabolic glucose control, panretinal ALP, and proliferative diabetic retinopathy (P < 0.05), but not with duration of diabetes (P > 0.05).

CONCLUSIONS

The results of the study indicate that poor metabolic control, panretinal ALP, and proliferative diabetic retinopathy are high risk factors for ocular surface disorders in type 2 diabetes. These patients should be followed more carefully, and should be referred to an ophthalmologist when required.

Clinical indications for penetrating keratoplasty in Maharaj Nakorn Chiang Mai Hospital, 1996-1999

PURPOSE

To determine the leading indication for penetrating keratoplasty.

MATERIAL AND METHOD

The authors retrospectively performed a chart review of the hospital records of all patients who underwent penetrating keratoplasty at Maharaj Nakorn Chiang Mai Hospital between January 1996 and December 1999.

RESULTS

A total of 45 corneal transplants were performed. The leading indications for penetrating keratoplasty, in order of decreasing frequency, were bullous keratopathy (28.9%), corneal scar (22.2%), corneal dystrophy and degeneration (20.0%), corneal ulcer (17.8%), regraft (8.9%), and trauma (2.2%).

CONCLUSION

Bullous keratopathy was the leading indication for penetrating keratoplasty at Maharaj Nakorn Chiang Mai Hospital from 1996 to 1999, followed by corneal scar. The major cause of bullous keratopathy was associated with posterior chamber intraocular lens implantation.

Corneal blindness in a southern Indian population: need for health promotion strategies

AIM

To assess the distribution and causes of corneal blindness in a population in southern India.

METHODS

A total of 11 786 people of all ages from 94 clusters representative of the population of the Indian state of Andhra Pradesh were sampled using a stratified, random, cluster, systematic sampling strategy. These participants underwent a detailed interview and eye examination including measurement of visual acuity with logMAR charts, refraction, slit lamp biomicroscopy, applanation tonometry, gonioscopy, and stereoscopic dilated fundus evaluation. An eye was considered to have corneal blindness if the visual acuity was <20/200 due to a corneal disease.

RESULTS

Of those sampled, 10 293 (87.3%) people participated in the study. Corneal blindness in at least one eye was present in 86 participants, an age, sex, and urban-rural distribution adjusted prevalence of 0.66% (95% confidence interval 0.49 to 0.86), which included 0.10% prevalence of corneal blindness in both eyes and 0.56% in one eye. The most frequent causes of corneal blindness in at least one eye included keratitis during childhood (36.7%), trauma (28.6%), and keratitis during adulthood (17.7%). Nearly 95% of all corneal blindness was avoidable. Multivariate analysis showed that the prevalence of corneal blindness was significantly higher with decreasing socioeconomic status and with increasing age. Of the 99 eyes with corneal blindness, 51 (51.5%) had visual acuity of inaccurate projection of light or no perception of light.

CONCLUSIONS

There is a significant burden of corneal blindness in this population, the majority of which is avoidable. Eye health promotion strategies are warranted to raise awareness about the causes and prevention of corneal blindness.

[Epithelial ingrowth after LASIK--personal experience]

The current incidence of epithelial ingrowth after LASIK varies from 1% to 12%. After second procedure, it increases up to 32%. Known risk factors for this complication include epithelial defects at the time of surgery, or a history of recurrent corneal erosions, corneal basement membrane epithelial dystrophy, history of ingrowth in the other eye, hyperopic LASIK correction, flap instability, repeated LASIK surgeries. We performed 200 LASIK procedures. In 12 patients we found epithelial ingrowth. The follow up period was 2 years. We applied treatment: lifting and manual removal in 7 cases, phototherapeutic keratectomy in 3 cases. The rest of cases were under observation. Epithelial ingrowth is a relatively rare complication, following LASIK.

[Hypovitaminosis A in Brazil: a public health problem]

Vitamin A deficiency is considered one of the most important of the easily preventable public health problems in a number of countries, including Brazil. The objective of this study was to review the scientific literature in the MEDLINE and LILACS databases that was published between 1970 and 2000 concerning vitamin A deficiency, and to assess the occurrence of hypovitaminosis A in Latin America, especially Brazil. Our research showed that until around 1980 the public health concerns focused mainly on the importance of vitamin A in ensuring good vision. In the second half of the 1980s, epidemiological studies suggested that, on a population level, subclinical vitamin A deficiency could also have a negative effect on metabolic functions, with a great impact on childhood morbidity and mortality. Marginal vitamin A deficiency has been reported in all the regions of Brazil for which there are data available, with high prevalences in various age groups. This situation is inexcusable, given the health care technology and resources that are now available. There must be a commitment to reducing vitamin A deficiency in order to ensure the adequate development of future generations.

Time to resolution of contact lens-induced corneal warpage prior to refractive surgery

PURPOSE

To evaluate the resolution of contact lens-induced corneal warpage before keratorefractive surgery.

METHODS

We prospectively studied the eyes of 165 consecutive contact lens-wearing patients evaluated for keratorefractive surgery. Significant contact lens-induced corneal warpage was detected by comeal topography in 20 eyes of 11 patients. Manifested refraction, keratometry, and cornea topography were subsequently recorded during weekly or biweekly reevaluations and were compared with previous measurements for stability. Effects of age, sex, type, and duration of contact-lens wear and the recovery time period to stabilization were analyzed.

RESULTS

Overall, a 12% incidence of significant contact lens-induced corneal warpage was found. In patients demonstrating lens-associated warpage, the mean duration of prior contact lens wear was 21.2 years (range 10 to 30 years); lens use included daily wear soft (n=2), extended-wear soft (n=6), toric (n=4), and rigid gas-permeable contact lenses (n=8). Up to 3.0 diopter (D) refractive and 2.5D keratometric shifts accompanied by significant topography pattern differences were observed. The average recovery time for stabilization of refraction, keratometry (change within +/- 0.5D), and topography pattern was 7.8+/-6.7 weeks (range 1 to 20 weeks). Recovery rates differed between the lens types: soft extended-wear 11.6+/-8.5 weeks, soft toric lens 5.5+/-4.9 weeks, soft daily wear 2.5+/-2.1 weeks, and rigid gas-permeable 8.8+/-6.8 weeks.

CONCLUSION

We observed a 12% incidence of significant contact lens-induced corneal warpage in patients undergoing evaluation for keratorefractive surgery. Warpage occurred with all types of contact lens wear but resolved at different rates. To optimize the quality and predictability of keratorefractive procedures, an appropriate waiting period is necessary for contact lens-induced corneal warpage to stabilize. We suggest that resolution of corneal warpage be documented by stable serial manifested refractions, keratometry, and corneal topographic patterns before scheduling patients for keratorefractive surgery.

Decreased incidence of epithelial defects during laser in situ keratomileusis using intraoperative nonpreserved carboxymethylcellulose sodium 0.5% solution

PURPOSE

To evaluate the incidence of epithelial defects that occur with laser in situ keratomileusis (LASIK) using nonpreserved carboxymethylcellulose sodium 0.5% solution (Refresh Plus(R)) intraoperatively.

SETTING

Community-based refractive center.

METHODS

This retrospective study comprised 105 patients (210 eyes) who had primary bilateral LASIK by 1 of 2 surgeons between October 1 and December 1, 2000. The 114 eyes treated subsequent to November 1, 2000, received Refresh Plus intraoperatively, and the 96 eyes treated before this date did not. The incidence of epithelial defects and diffuse lamellar keratitis (DLK) in both groups was recorded. The preoperative keratometry measurements of all cases were also recorded.

RESULTS

There was a statistically significant decrease in the incidence of epithelial defects in the group that received Refresh Plus intraoperatively (P =.02). No statistically significant between-group difference in the incidence of DLK was detected. Analysis of the keratometry measurements revealed no statistically significant association between the amount or axis of astigmatism and the incidence of epithelial defects or DLK.

CONCLUSION

The intraoperative use of nonpreserved Refresh Plus significantly decreased the rate of epithelial defects that occurred during LASIK.

Vitamin A deficiency disorders in 16 districts of India

A multicentre study to assess vitamin A deficiency disorders (Bitot's spot and corneal scars) in 164,512 children (< 6 years) and night blindness among 113,202 children (24-71 months) from 16 districts of 11 states was carried out during 1997-2000. The prevalence of night blindness among 6,633 pregnant women from 15 districts was also assessed. The sampling methodology followed was a "30 cluster survey". The highest prevalence of Bitot's spot (4.71%), corneal scar (0.5%) and night blindness (5.17%) in children was found in Gaya district whereas the highest prevalence of night blindness (19.62%) among pregnant women was observed in Dibrugarh. No case of Bitot's spot was found in children screened from Mandi, Dehradun and Badaun districts. Similarly prevalance of night blindness was 'nil' among pregnant women of Badaun, Baramulla, Dehradun, Mainpuri, Srinagar, Bikaner and Raigarh.

Prevalence of astigmatism in infant monkeys

PURPOSE

Human infants exhibit a high prevalence of astigmatism. Although macaque monkeys are commonly used as animal models in experiments on early ocular growth and emmetropization, the prevalence of astigmatism in infant monkeys is unexplored. In this study we examine the prevalence and nature of astigmatism in infant monkeys.

METHODS

Refractive and corneal astigmatism were measured in 132, 2-5-week-old rhesus monkeys (Macaca mulatta) using cycloplegic retinoscopy and keratometry, respectively. Longitudinal measures of refractive development were obtained from 16 normal infants over the first 6 months of life.

RESULTS

Infant monkeys exhibited a low prevalence of astigmatism. Approximately 90% of the 2-5-week-old infants had <1.00 D of either refractive or corneal astigmatism. When refractive astigmatism was observed, it was well correlated with the direction and magnitude of corneal astigmatism. When corneal astigmatism was >1.00 D (n=20), it was predominantly against-the-rule in nature (70.0%). The infant monkeys that were followed longitudinally rarely showed significant astigmatic errors at any time during the observation period. When these infant monkeys exhibited significant astigmatism, it was usually transient and not present on subsequent measurements.

CONCLUSIONS

Unlike human infants, infant monkeys exhibit relatively little astigmatism. The low prevalence of astigmatism during early development suggests that astigmatism does not provide an essential cue for vision-dependent eye growth in infant primates.