X linked dominant congenital isolated bilateral ptosis: the definition and characterisation of a new condition

AIMS—To characterise the inheritance of ptosis in one particular pedigree.
METHODS—The pedigree was analysed clinically and genetically to assess the mode of inheritance and to ascribe a gene locus for the condition.
RESULTS—Affected members of the pedigree have bilateral symmetrical congenital isolated ptosis, a condition which is linked to genetic markers on the X chromosome in this family.
CONCLUSION—A pedigree with dominantly inherited congenital bilateral ptosis is presented. The pedigree exhibits X linked dominant inheritance. A new ophthalmic condition was thereby characterised—namely, X linked dominant congenital isolated bilateral ptosis.

     

High spatial resolution automated perimetry in glaucoma

BACKGROUND—Automated perimetry is of fundamental importance in assessing visual function in glaucoma. A technique was evaluated to perform high spatial resolution automated perimetry to allow a more detailed assessment of the luminance sensitivity in selected regions of the visual field than is possible with conventional perimetry.
METHOD—High spatial resolution perimetry was performed using a Humphrey automated perimeter by measuring luminance sensitivity across a 9 by 9 degree custom grid of 100 test locations with a separation between adjacent locations of 1 degree. Quantitative analysis of the raw and Gaussian filtered thresholds was performed to assess the repeatability of the technique in normals, glaucoma suspects, and glaucoma patients.
RESULTS—The testing protocol was well tolerated by all subjects. High spatial resolution perimetry in glaucomatous eyes demonstrated fine luminance sensitivity loss not suspected with conventional perimetry. High spatial resolution perimetry also demonstrated reproducible areas of sensitivity loss in some glaucomatous eyes in areas of the visual field which appear normal with conventional programmes. The repeatability of the technique correlated with mean threshold sensitivity and was substantially improved to clinically acceptable levels by Gaussian filtering the thresholds.
CONCLUSION—This technique of high spatial resolution perimetry allows the practical assessment of selected regions of the visual field at higher resolution than conventional perimetry, and may be clinically useful in glaucoma.

     

Reproducibility of topographic measures of the glaucomatous optic nerve head

AIMS/BACKGROUND—Laser scanning tomography provides an assessment of three dimensional optic disc topography. For the clinical purpose of follow up of glaucoma patients, the repeatability of the various measured variables is essential. In the present study, the reproducibility of morphometric variables calculated by the topographic scanning system, TopSS (Laser Diagnostic Technology, San Diego, CA) was investigated.
METHODS—Two independent measurements (30 minutes apart) each consisting of three complete images of the optic disc were performed on 16 eyes of 16 glaucoma patients using a TopSS. The instrument calculates 14 morphometric variables for the characterisation of the optic disc.
RESULTS—From the two tailed paired tests, all variables were seen to have good reproducibility. However, correlation and regression analyses showed that only the three variables, volume below, half depth area, and average cup depth, are acceptably reproducible.
CONCLUSION—The TopSS provides three variables which describe the physiological shape of the optic disc that have high reproducibility. These three variables might be useful for following the progression of optic disc changes in glaucoma patients.

Keywords: optic nerve head; scanning laser; glaucoma; tomography     

Botulinum toxin A treatment of overactive corrugator supercilii in thyroid eye disease

BACKGROUND/AIM—Patients with thyroid eye disease with upper eyelid retraction often develop overaction of the accessory muscles of eyelid closure, the glabellar muscles corrugator supercilii and procerus. The resultant glabellar furrowing (frown lines) contributes to the typical thyroid facies. The aim of this study was to evaluate the use of botulinum toxin A reversible chemodenervation of the glabellar muscles as adjunctive treatment in the rehabilitation of patients with thyroid eye disease.
METHODS—14 patients (13 females) ages 39-76 years (mean 52) with inactive thyroid eye disease and associated medial eyebrow ptosis and prominent glabellar frown lines were recruited. All patients had a history of upper eyelid retraction. Each patient was treated with a single botulinum toxin injection (Dysport 0.2 ml, 40 units) into each corrugator supercilii and sometimes procerus muscles as an outpatient procedure. The effectiveness and acceptability of the treatment was assessed clinically and from a patient questionnaire.
RESULTS—The injections were tolerated by 13/14 (93%) patients. There was resultant flattening of the glabellar region and improvement of medial eyebrow contour in all patients, with onset of paralysis within 1 week. All patients reported a subjective improvement in appearance. Side effects included one patient (7%) with reversible partial ptosis. The beneficial effect lasted 4-6 months, with a gradual return of function. Repeat treatment was indicated where there was persistent upper eyelid retraction and protractor overaction.
CONCLUSION—Botulinum toxin A chemodenervation of the glabellar muscles in these patients was effective and acceptable. Chemodenervation should be considered in the rehabilitation of patients with thyroid eye disease where there is upper eyelid retraction and overacting protractors resulting in a thyroid frown. Once the eyelid retraction has been successfully treated by surgery, the need for further glabella muscle chemodenervation is considerably reduced.

Keywords: botulinum toxin A; corrugator supercilii; frown lines; thyroid eye disease     

Complications of fascia lata harvesting for ptosis surgery

AIMS/BACKGROUND—The aim of this study was to assess the morbidity associated with harvesting autogenous fascia lata for brow suspension ptosis surgery.
METHODS—A retrospective study by postal questionnaire of 24 consecutive patients.
RESULTS—Early postoperative problems with pain on walking (67%), limping (38%), and wound pain (57%) occurred mostly for less than 1 week. The final cosmetic appearance of the scar caused minor concern in 38% of patients.
CONCLUSION—Fascia lata is the preferred material for permanent ptosis correction when a brow suspension is required. Most of the patients, following fascia lata harvest, experienced some symptoms of leg pain and limping for less than 1 week. The only long term problem was the scar. 38% of patients found the final cosmetic appearance caused minor concern.

     

Split thickness buccal mucous membrane grafts and β irradiation in the treatment of recurrent pterygium

BACKGROUND—Pterygium is a common problem and after surgical removal may recur in up to 80% of cases, depending on the technique of primary excision. Recurrent pterygia can be aggressive and repeated excision may result in severe conjunctival scarring and shortening, resulting in insufficient conjunctiva to perform further grafting and lid surgery. When there is insufficient autologous conjunctiva, mucous membrane must be obtained from other sites. Full thickness buccal mucous membrane grafts have been described, but they may result in a beefy red appearance, with graft contraction and a poor tear film.
METHOD—The use of split thickness buccal mucous membrane grafts is described in three patients with recurrent pterygium, two in combination with lamellar keratoplasty. β Irradiation was used as adjuvant therapy in all cases.
RESULTS—In all three cases an acceptable cosmetic appearance was achieved, with no recurrence of the pterygium, and a good range of eye movements.
CONCLUSIONS—It is recommended that split thickness buccal mucosal grafts, combined with β irradiation, should be considered in complex cases of pterygium recurrence when there is insufficient autologous conjunctiva and conjunctival shortening with restricted eye movements.

Keywords: pterygium; split thickness buccal mucous membrane graft; β irradiation     

A clinic based survey of blindness and eye disease in Cambodia

AIMS—To survey the spectrum of eye disease presenting to rural eye clinics in Cambodia.
METHODS—A total of 1381 patients seen consecutively at 13 eye clinics were examined and the findings recorded.
RESULTS—231 (16.7%) were bilaterally blind (visual acuity <3/60 in both eyes); 263 (19%) were unilaterally blind, and 169 (12%) had low vision (visual acuity <6/18 in the better eye). Cataract was the commonest cause of visual loss in all three categories and was responsible respectively in 69%, 40%, and 55% of each group. Trachoma was diagnosed in 13% of patients. Thirty three of them needed lid surgery for trichiasis.
CONCLUSION—With the difficult practical and political situation in Cambodia there seems little prospect of making substantial inroads into the backlog of avoidable blindness in the near future.

     

Reproducibility and accuracy of measurements with a hand held autorefractor in children

AIM—To determine reproducibility and accuracy of the Nikon Retinomax autorefractor when used with children who were made cycloplegic.
METHODS—Autorefraction and retinoscopy or subjectively refined retinoscopy (where, under the patient's direction, the refraction was varied until the best visual acuity was achieved) were performed on the right eye of 47 children, age 11-93 months. Autorefraction was performed using the Nikon Retinomax, which provides up to eight measured values of refractive error and one representative measurement of refractive error.
RESULTS—Autorefractor measurements were successfully obtained from 7/9 children age 3 years or younger, and from all older children. Vector methods were used to calculate differences. Retinomax reproducibility averaged 0.43 D. Unbiased Retinomax and retinoscopy measurements differed by an average of 0.82 D. Unbiased Retinomax and subjectively refined retinoscopy differed by an average of 1.03 D.
CONCLUSIONS—Reproducibility of Retinomax measured values in children is comparable with reproducibility of retino scopy, subjective refraction, and autorefraction measurements in adults. Agreement between Retinomax and retinoscopy and agreement between Retinomax and subjective refinement in children is comparable with agreement between autorefraction and subjective refraction in adults. The study indicates that the Retinomax is a useful instrument for measuring refractive errors in young children.

     

Clinical evaluation of scanning laser polarimetry: I Intraoperator reproducibility and design of a blood vessel removal algorithm

AIMS—To evaluate the reproducibility of the retardation values (change in polarisation) obtained with the scanning laser polarimeter in a series of normal subjects and glaucoma patients. To improve the analysis of the raw data by devising and evaluating a blood vessel removal algorithm.
METHODS—Scanning laser polarimetry was performed on 10 normal subjects and 10 glaucoma patients. A series of six images was obtained from each eye. The normal subjects were re-imaged 3 months after their initial assessment. The retardation values obtained from each eye were analysed using the authors' own methods, including the use of an algorithm to remove blood vessels from the polar profiles. The reproducibility of these measurements and the performance of the blood vessel removal algorithm were assessed.
RESULTS—The "individual point" coefficient of variation was approximately 12.5% for normal subjects and 17.0% for glaucoma patients. The "integral" coefficient of variation for these groups was approximately 5.5% and 9.5% respectively. The reproducibility of the measurements did not improve with an increased number of measurements. There was no difference in the reproducibility of the measurements in normal subjects over time. The blood vessel removal algorithm improved the reproducibility of the measurements when the shape of the profile was assessed.
CONCLUSION—The intraoperator reproducibility of retardation values obtained with the scanning laser polarimeter is satisfactory for its use as a clinical tool. The use of a blood vessel removal algorithm improves the reproducibility of the measurements and also assists the clinician in the interpretation of the polar profiles. Furthermore, it allows the construction of normal database polar profiles, thereby enabling the identification, location and quantification of retinal nerve fibre layer damage in an "at risk" individual's polar profile.

Keywords: scanning laser polarimetry; glaucoma; reproducibility; algorithm     

Basal cell carcinoma of the eyelids and solar ultraviolet radiation exposure

AIMS—To compare the distribution of eyelid basal cell carcinoma (BCC) with the relative ultraviolet radiation (UVR) exposure to different sites on the eyelids.
METHODS—The location of BCC on the eyelids was allocated to one of seven regions. The UVR exposure was recorded with a polymer film attached to the eyelids at seven sites in a manikin and in human subjects.
RESULTS—Localisation of the 329 tumours was mainly on the lower eyelids (225 tumours), and the medial canthal regions (87 tumours). There was no association between UVR doses at the seven sites of the eyelids and the location of BCCs. The UVR exposure was similar on the upper and lower eyelids, while the number of tumours on the lower eyelids outnumbered the upper lids by a factor of 13 (17 upper, 225 lower)
CONCLUSION—UVR exposure only partially explains the aetiology of periorbital BCC.

Keywords: polysulphone film; basal cell carcinoma; ultraviolet radiation; eyelid     

Reliable keratometry with a new hand held surgical keratometer: calibration of the keratoscopic astigmatic ruler

AIM—Some surgeons consider hand held surgical keratometers unreliable. This may be due to incorrect use through not realising that the distance that the keratometer is held from the cornea influences the shape of the image. When a keratometer is held closer to the astigmatic cornea, the elliptical image will appear more circular, particularly for larger degrees of astigmatism. However, the keratoscopic astigmatic ruler (KAR) has design features that correct the hitherto unrecognised problems with the use of a hand held keratometer. This study assesses the reliability and accuracy of measurement of astigmatism using the KAR.
METHODS—The KAR and the Bausch & Lomb keratometer (B&L) were compared using six back surface toric cut contact lens blanks representing 1 to 6 dioptres of astigmatism. Two observers (one experienced in the use of the keratometers, the other a novice) took eight randomly repeated "masked" measurements of each lens blank with the KAR and four measurements with the B&L in a similar fashion.
RESULTS—There was no difference between the measurements with either instrument by each of the observers (p=0.95, ANOVA). The standard error of measurement for the KAR was 0.59 D, for the B&L, 0.31 D. The intraclass correlation coefficient of reliability for the KAR was 0.90 and for the B&L it was 0.97. The coefficient of repeatability for the KAR was plus or minus 0.83 D, and for the B&L plus or minus 0.77 D. The interobserver reliability for the KAR was 0.898, and for the B&L, 0.975.
CONCLUSION—These results suggest that the KAR has good reliability and reproducibility and compares favourably with the B&L keratometer. Inexperience with use does not affect reliability.

     

Heidelberg retinal flowmetry: factors affecting blood flow measurement

AIMS—To evaluate factors affecting Heidelberg retinal flowmeter (HRF) measurements of retinal and optic nerve head blood flow in human subjects.
METHODS—The angle of incidence between laser beam and fundus, and camera distance from the eye, were evaluated for their effect upon measures of blood volume, velocity, and flow in a single 100 × 100 × 400 µm volume of temporal peripapillary retinal tissue in normal volunteers. Both intra and intersession reproducibility of these measures were studied. Intersession data were obtained by taking one image per week for 4 weeks. Finally, the intersession haemodynamic data were examined in the entire image (640 × 2560 × 400 µm), using histograms of pixel by pixel blood flow.
RESULTS—Measures of blood volume, velocity, and flow from a single anatomical site were unaffected by laser beam to fundus angle of incidence (n = 12). As camera distance from the eye was increased (from 2 to 5 to 7 cm), flow measurements showed increasing individual changes, despite unaltered measured vessel lengths and constant overall mean flow (n = 14). The coefficient of variation for two intrasession images of optic nerve head blood flow averaged 7% (n = 20); in contrast, the 4 week intersession coefficient of variation averaged 30% (n = 15). Intersession reproducibility was increased by using flow histograms from the entire image: the coefficients of variation averaged 16% for total flow and 17% for flow in the pixel of median flow.
CONCLUSION—HRF measures of flow are independent of the laser beam to fundus angle of the incidence and dependent upon camera distance from the eye. Intersession reproducibility is best using pixel by pixel analysis of the entire image.

Keywords: retina; optic nerve head; glaucoma; diabetic retinopathy     

Scanning laser polarimetry of the retinal nerve fibre layer in primary open angle and capsular glaucoma

AIMS—To evaluate the clinical value of scanning laser polarimetry with the nerve fibre analyser type II in primary open angle glaucoma (POAG) and capsular glaucoma.
METHODS—Scanning laser polarimetry was performed on one eye of 30 patients suffering from POAG, 25 patients suffering from capsular glaucoma, and on 35 healthy control subjects. The retinal nerve fibre layer (RNFL) thickness values were compared among the groups. Reproducibility of the measurements was calculated and the influence of pilocarpine induced miosis on the results was investigated.
RESULTS—RNFL thickness in the superior and inferior sectors, as well as along the total circumference was significantly lower in both glaucoma groups than in the control eyes (p<0.05). None of the thickness values differed between the two glaucoma groups. Reproducibility was comparable in all groups; the coefficient of variation varied between 3.0% and 8.9% for the different sectors investigated. Miosis had no significant impact either on the thickness values or on the reproducibility (p>0.05).
CONCLUSION—The results suggest that scanning laser polarimetry is a useful method for nerve fibre layer analysis in glaucoma, and that it is not influenced by the pupil size.

     

Computer algorithms for the automated measurement of retinal arteriolar diameters

AIMS—Quantification of retinal vascular change is difficult and manual measurements of vascular features are slow and subject to observer bias. These problems may be overcome using computer algorithms. Three automated methods and a manual method for measurement of arteriolar diameters from digitised red-free retinal photographs were compared.
METHODS—60 diameters (in pixels) measured by manual identification of vessel edges in red-free retinal images were compared with diameters measured by (1) fitting vessel intensity profiles to a double Gaussian function by non-linear regression, (2) a standard edge detection algorithm (Sobel), and (3) determination of points of maximum intensity variation by a sliding linear regression filter (SLRF). Method agreement was analysed using Bland-Altman plots and the repeatability of each method was assessed.
RESULTS—Diameter estimations obtained using the SLRF method were the least scattered although diameters obtained were approximately 3 pixels greater than those measured manually. The SLRF method was the most repeatable and the Gaussian method less so. The Sobel method was the least consistent owing to frequent misinterpretation of the light reflex as the vessel edge.
CONCLUSION—Of the three automated methods compared, the SLRF method was the most consistent (defined as the method producing diameter estimations with the least scatter) and the most repeatable in measurements of retinal arteriolar diameter. Application of automated methods of retinal vascular analysis may be useful in the assessment of cardiovascular and other diseases.

     

Echographic measurements of the retrobulbar optic nerve in normal and glaucomatous eyes

AIM—A study was designed to investigate whether measurements of the optic nerve diameter (OND) and cross sectional area (ONCSA), as measured by B-scan ultrasonography, are altered in glaucoma. The reproducibility and test-retest variability of echographic estimates of retrobulbar optic nerve dimensions was also tested.
METHODS—One eye of 49 glaucoma patients and 90 control subjects underwent five repeated echographic measurements of the maximal interpial diameter and cross sectional area of the orbital optic nerve on two separate occasions. All measurements were taken by one experienced ultrasonographer.
RESULTS—Mean optic nerve diameter (SD) for the control group was 2.86 (0.46) mm, and was independent of height (multiple regression analysis: p = 0.21), axial length (p = 0.74), spherical equivalent (p = 0.97), sex (ANOVA: p=0.36), or race (p=0.14), but was inversely related to age (p = 0.01). Reproducibility of OND readings in control subjects was 0.149 mm (coefficient of repeatability). Test-retest variability of interpial diameter was −0.02 (0.29) mm. Mean interpial diameter of the optic nerve was significantly smaller among glaucomatous eyes (2.58 (0.501) mm) than controls (Mann-Whitney U test: p < 0.0001). Glaucomatous optic nerves also had a significantly smaller cross sectional area (6.68 (2.58) mm²) than those of healthy volunteers (8.25 (1.67) mm²) (p = 0.004).
CONCLUSION—Echographic measurements of the orbital optic nerve are highly reproducible and not subject to clinically meaningful test-retest variability. Optic nerve interpial diameter and cross sectional area are reduced in glaucomatous eyes, reflecting nerve fibre loss. This technique may be useful in distinguishing between normal and glaucomatous eyes where optic disc morphometry is inconclusive or impossible as a result of opaque media.

Keywords: glaucoma; optic nerve; ultrasound     

MIB-1 and PC-10 immunostaining for the assessment of proliferative activity in primary acquired melanosis without and with atypia

AIMS—To compare the proliferative activity of intraepithelial melanocytes in primary acquired melanosis (PAM) without atypia and PAM with atypia by immunohistochemical staining for the Ki-67 antigen and the proliferating cell nuclear antigen (PCNA).
METHODS—Formalin fixed, paraffin embedded sections from 35 archival specimens of PAM without atypia (n=19) and with atypia (n=16) were studied by immunostaining with MIB-1 and PC-10 monoclonal antibodies that react with the Ki-67 antigen and PCNA respectively. The results were calculated as the mean number of positive cells per eyepiece grid. All specimens were evaluated by two masked observers, and the interobserver reproducibility was assessed.
RESULTS—The means of the positive cell count in PAM with atypia were significantly higher compared with PAM without atypia for both observers, in both the PC-10 and the MIB-1 stained sections. In a linear least square model that estimated the interobserver and between group variation, the difference of MIB-1 and PC-10 positive cell count between PAM without and with atypia remained highly significant. The difference between the observers was not significant.
CONCLUSIONS—Immunostaining with MIB-1 and PC-10 demonstrated that PAM with atypia has higher proliferative activity than PAM without atypia. This method was found to be reproducible between different observers.

Keywords: primary acquired melanosis; immunostaining; atypia     

RA/DA cumulative curve analysis of local and diffuse neuroretinal rim area damage in glaucoma patients

AIM—To evaluate the validity of cumulative rim/disc area (RA/DA) curve analysis as a clinical tool for the identification of glaucoma induced optic disc pathology.
METHODS—71 normal and 83 glaucomatous eyes were evaluated from a series of 154 subjects recruited for this study. For each eye, the cumulative distribution of RA/DA was calculated from 36 equally spaced rim sectors of each optic disc obtained by the automatic evaluation of simultaneous videographics (Image-net X Rev.3/51b). To increase the sensitivity of this analysis in early glaucoma and in normal eyes, these cumulative curves were subsequently divided into two equal segments and the slopes of their respective regression lines compared.
RESULTS—The median RA/DA value obtained from the 36 sectors was significantly different in glaucomatous eyes compared with normals (p <0.001). Nevertheless, the curves (5th-95th percentile of the cumulative curves distribution) of early glaucomatous eyes fell within the normal range. When the cumulative curve of these marginal cases was then divided into two equal segments, the comparison of the slopes of the regression lines showed a significant difference (p <0.05) in 100% of early glaucomatous eyes. Furthermore, normal eyes were shown to be true negatives in 93% of the cases in which no significant difference between the two slopes was observed.
CONCLUSION—Analysis of the RA/DA cumulative curve from 36 sectors of the optic disc was a valid method for the identification of glaucomatous disc pathology; however, a further calculation of the slopes of the two RA/DA regression lines was needed to identify early glaucomatous damage.

Keywords: glaucoma; optic disc morphometry; rim/disc area cumulative curves     

Clinical evaluation of keratometry and computerised videokeratography: intraobserver and interobserver variability on normal and astigmatic corneas

AIMS—To evaluate intra- and interobserver variability in measurements on normal and astigmatic corneas with keratometry and computerised videokeratography.
METHODS—Keratometric readings with the 10 SL/O Zeiss keratometer and topographic maps with the TMS-1 were obtained by two independent examiners on 32 normal and 33 postkeratoplasty corneas. Inter- and intraobserver coefficients of variability (COR) for measurements of steep and flat meridian power and location, in addition to the magnitude of astigmatism, were assessed.
RESULTS—Compared with TMS-1, the 10 SL/O keratometer showed a superior repeatability in measuring normal corneas (intraobserver COR for keratometry and TMS-1 respectively: 0.22 and 0.30 D for steep meridian power; 0.18 and 0.44 D for flat meridian power; 0.26 and 0.40 D for astigmatism; 5° and 26° for steep meridian location; 5° and 13° for flat meridian location). Astigmatism intraobserver COR (0.20 D and 0.26 D for the two observers) and interobserver COR (0.28 D) of the keratometer for normal corneas was very good and not affected by observers' experience. Repeatability of the TMS-1 on normal corneas was found to be: (a) observer related, and (b) astigmatism related. A novice observer showed a much greater COR (1.62 D for astigmatism, 30° for flat meridian location) compared with the experienced examiner (0.40 D for astigmatism, 13° for flat meridian location). Higher deviation scores were observed for corneas with higher astigmatism. For the postkeratoplasty corneas, again the keratometer achieved superior reproducibility (astigmatism interobserver COR 1.12 D for keratometry, 4.06 D for TMS-1; steep meridian location interobserver COR 10° for keratometry, 34° for TMS-1).
CONCLUSION—Keratometric readings are more reproducible than topographic data both for normal and postkeratoplasty corneas. The two instruments should not be used interchangeably especially on highly astigmatic corneas. For the TMS-1, users with the same level of experience should be employed in clinical or experimental studies.

Keywords: keratometry; computerised videokeratography; astigmatic corneas     

Dry eye and Meige's syndrome

AIMS—To determine the relation between dry eye and Meige's syndrome.
METHODS—325 patients with dry eye were divided into those responsive to topical and other forms of treatment (n=276) and those who were not (n=49). A neuropsychiatric examination was performed to check for Meige's syndrome in the latter group.
RESULTS—Twenty eight (57%) of the treatment unresponsive patients were diagnosed with Meige's syndrome.
CONCLUSIONS—There is a subgroup of patients with dry eye who do not respond to simple therapy. More than half of these patients have Meige's syndrome and need psychiatric, as well as ophthalmic, care.

     

National survey of blindness and low vision in Lebanon

AIMS—To survey level of blindness and low vision in Lebanon.
METHODS—A population survey was undertaken in 10 148 individuals to measure the prevalence and identify the causes of blindness in Lebanon.
RESULTS—The prevalence of blindness was 0.6% and that of low vision 3.9%. The major causes of blindness were cataract (41.3%) and uncorrected large refractive error (12.6%).
CONCLUSION—Most causes of blindness in Lebanon can be controlled by various educational and medical programmes.