Angelo Macrì

Fluctuations of Intraocular Pressure during the Day in Open-Angle Glaucoma, Normal-Tension Glaucoma and Normal Subjects

Purpose: The aim of the present paper is to describe the variations in intraocular pressure (IOP) during the day in normals, in patients with primary open-angle glaucoma (POAG) and in patients with normal-tension glaucoma (NTG). IOP represents one of the most important risk factors for glaucoma. However the IOP value is not constant during the day and IOP fluctuation could influence the diagnostic and prognostic evaluation of the glaucomatous disease. Methods: For this purpose IOP was evaluated every 2 h from 8 a.m. to 8 p.m. in one randomized eye of 33 normal subjects, 95 POAG and 50 NTG patients. Results: The results show that the highest IOP values were detectable in the morning in all three groups. The lowest values were found in the early afternoon hours. These variations were most evident in POAG patients. The daily IOP fluctuations were directly proportional to IOP level. Conclusion: The study evidents that a single tonometric evaluation, especially if done in the first hours of the afternoon, is not sufficient to correctly evaluate the IOP-related risk in glaucoma patients. If the pressure peaks are important in determining the extent of glaucomatous damage in NTG patients IOP should not have an important role in optic nerve head damage. The use of diurnal curves seems to be mandatory for the assessment of IOP-related risk and of efficiency of the therapeutic approach.

LOW SPATIAL-CONTRAST SENSITIVITY IN DRY EYES

PURPOSE Blurred vision in keratoconjunctivitis sicca eyes could be the result of the loss of the glossy surface of the tear film because of changes in composition or thickness irregularities. Spatial-contrast sensitivity in keratoconjunctivitis sicca and normal control eyes was tested before and after a tear substitute. METHODS Three different groups of subjects were enrolled: one group of dry eyes with nonsignificant signs of epithelial disease (n = 12), the second group of dry eye positive with 1% Bengal rose staining of the cornea and of the conjunctiva (n = 18), and a third of normal eyes as control group (n = 15). In all the 45 eyes, spatial-contrast sensitivity was tested under the best correction by means of the Vistech Multivision Contrast Tester 8000 (Vistech Consultants, Dayton, OH, U.S.A.) before and 15 min after the instillation of a 0.4% Na-hyaluronate tear substitute without preservatives. RESULTS A significant decrease of spatial-contrast sensitivity ranging from 35 to 70% was present in keratoconjunctivitis sicca eyes compared with a third group of age-matched normal eyes used as control. The spatial-contrast sensitivity was significantly lower also in the presence of preserved corneal surface. The addition of a tear substitute improved spatial contrast-sensitivity thresholds in all groups. CONCLUSION Tear-film disease can affect the transfer function of modulation of the ocular surface.

Forecasting of hydrophilic contact lens tolerance by means of tear ferning test

Abstract · Background: The ability of the tear ferning test to predict future hydrophilic contact lens tolerance was studied. · Methods: The tear ferning test (TFT) was performed on one randomly chosen eye of each of the 116 subjects who came to our contact lens clinic for hydrophilic contact lens application. The TFT was performed at the time of enrollment (T0) and then 1 month (T1), 3 months (T2) and 6 months (T3) after contact lens fitting. The specificity and the sensitivity of the TFT in identifying future contact lens tolerance was then studied. The statistical significance of the differences in behavior through the study period among the subjects with different pre-fitting TFT results was evaluated by means of survival curves. · Results: When only type I ferning was considered as a marker of good tear film conditions, the ability of the TFT to forecast contact lens tolerance had 78.95% sensitivity, 78.35% specificity and 78.45% diagnostic precision. The TFT showed sensitivity of 100%, specificity of 86.6% and diagnostic precision of 97.4% when performed after 1 month of contact lens wearing (T1). Survival curve analysis showed a statistically significant difference in behavior between the group of subjects with pre-fitting ferning type I and the other three groups (P<0.001). · Conclusion: The TFT appears to have good sensitivity and specific for prediction of contact lens tolerance in a clinical setting.

Evaluation of the Analgesic Effect of 0.1% Indomethacin Solution on Corneal Abrasions

Purpose: The authors wished to verify the analgesic action of 0.1% indomethacin in a water-based solution on patients affected by traumatic corneal abrasions. Methods: 347 patients affected by traumatic corneal abrasions, having been randomly divided into 2 groups on the basis of the administration of indomethacin, were evaluated at 30 min, 12 h and 24 h after the initial treatment of the abrasion. The level of pain experienced was evaluated on a verbal pain scale and the healing time was evaluated relative to the dimension of the abrasion. Results: The pain level was initially overwhelming for both groups: p = 0.737; at successive check-ups it was possible to verify a reduction of the symptomatology, with a more pronounced decrease in pain in the group treated with indomethacin (p < 0.0001), which also demonstrated a lower sensitivity to pain in the case of larger lesions (p < 0.0001). There was no difference in the healing time between groups, and the reduction of pain is not correlated with corneal anesthesia and healing time. Conclusions: Our study highlighted the efficacy of indomethacin as a pain reducer for acute corneal pathology and suggested that the medication may act on the corneal nociceptors in a qualitative way.

Echographic study of extraocular muscle thickness in children and adults.

Background Echobiometric evaluation of extraocular muscles in normal subjects has been performed previously, but only in adults. We determined extraocular muscle thickness in normal subjects in three age groups.Methods Extraocular muscle thickness was studied in 75 normal subjects divided into three age groups (5.10, 11.15 and 28.37 years) using a Biovision B-scan-S instrument in standardized A-mode (frequency, 10 MHz; biometry resolution, 0.15 mm; depth, 40.60 mm; points on X axis, 512; levels on Y axis, 256). All measurements were performed by the same operator and repeated five times. The reproducibility of the technique was determined using the coefficient of variation. The one-way ANDV A test was used to compare the three groups, and the two-tailed unpaired t-test was used to compare subjects aged 5.10 years and those aged 11.15 years, and subjects aged 11.15 years with those aged 28.37 years.Results The technique showed good reproducibility. In subjects 5.10 years old, the coefficient of variation was 8%; in subjects 11.15 years and 28.37 years old, it was 5%. Increased muscle thickness was observed with age (p < 0.001). A statistically significant difference between the medial and inferior recti muscles in subjects 11.15 years and 28.37 years old was found (p < 0.001).Conclusions The increased thickness of all recti muscles may be influenced by growth (primarily during puberty), and the variations in thickness of the extraocular muscles may be attributable to near-vision stimulus of the inferior and medial recti muscles.

Use of a Questionnaire for the Diagnosis of Tear Film-Related Ocular Surface Disease

Dry eye is defined as a disorder of the tear film, due to tear deficiency and/or tear evaporation that causes damage to the ocular surface and is associated with symptoms of ocular discomfort. This definition clearly underlines that subjective symptoms have a relevant part in the manifestation of the disease. Although collecting ocular surface signs have become rather standardized, symptom collection and their relevance as a diagnostic indicator have not yet been established. Furthermore, the frequent incongruence between the level of ocular surface damage and symptomatic complaints are characteristic of dry eye.

Effect of topical 0.1% indomethacin solution versus 0.1% fluorometholon acetate on ocular surface and pain control following laser subepithelial keratomileusis (LASEK).

Purpose: To compare the effect of topical 0.1% indomethacin solution versus 0.1% fluorometholon acetate in the early postoperative period after LASEK treatment. Methods: One hundred thirty-five patients undergoing LASEK, having been randomized in a double-masked manner into 2 groups (1 receiving indomethacin and 1 fluorometholon), were evaluated 2–4 days before and 4 days after treatment. We examined corneal fluorescein staining and corneal esthesiometry; the level of pain experienced was reported by the patient on a visual pain scale. In addition, haze was evaluated at 14 ± 1 weeks after surgery. Results: The pain level and corneal fluorescein staining were significantly less in the indomethacin group. Corneal esthesiometry was reduced to the same extent in the 2 groups. There were no statistically significant differences in haze presentation between the 2 groups. Conclusion: Our study highlights the efficacy of indomethacin solution compared with fluorometholon as a pain reducer after LASEK treatment and suggests that indomethacin is associated with a faster epithelial healing process.

Bacterial load and protein deposits on 15-day versus 1-day disposable hydrophilic contact lenses.

PURPOSE This study quantified the bacterial load and protein deposits on 1- and 15-day disposable contact lenses after use in normal wearers. METHODS Sixteen patients were randomly assigned to a 1-day contact lens (1-Day Acuvue) in one eye and to a 15-day contact lens (Acuvue) in the contralateral eye. Only one specified solution was allowed for the care of 15-day lenses. All patients were evaluated every month for 6 months (at times T1, T2, T3, T4, T5, T6). At times T1, T3, and T5, the lenses were removed in a sterile fashion and sent for laboratory quantification of Staphylococcus aureus and Pseudomonas aeruginosa. At T2, T4, and T6, quantification of protein deposits was determined, and at T0 and T6, impression cytology of the conjunctiva was performed. RESULTS P. aeruginosa was not identified on any lens. At T1, T3, and T5, S. aureus was significantly greater on the 1-day versus 15-day lenses (p < 0.001). In contrast, protein deposits were significantly greater on the 15-day lenses at all time points (T2, T6: p < 0.01; T4: p < 0.05). Impression cytology of the 15-day lens eyes revealed a worsening trend compared to the 1-day lens; however, no statistically significant differences were found between the two groups (p = 0.29). CONCLUSION Results of this study suggest that the use of cleaning and preservative solutions can alter the ocular surface bacterial environment of the contact lens wearer and that these changes are not a direct consequence of contact lens wear. The bactericidal activity of these solutions could, with time, also affect ocular surface cells, leading to contact lens intolerance and ocular surface disease.

Optic disc surface smoothness and visual field indices.

Abstract · Background: In order to ascertain whether the optic disc surface smoothness (ODSS) could be used to predict the amount of visual field damage in glaucomatous eyes, the correlations between ODSS and visual field indices were evaluated. · Methods: One eye was randomly chosen from each of 40 normals and 50 patients with glaucoma. The morphology of the optic disc surface was analyzed using the Topcon IMAGEnet X Rev-3.51b. In order to define the level of “smoothness” of the optic disc surface, the differences of the relative position of each surface point was studied by measuring the standard deviation (SD) from the average height of the points (number of points ranged from 623 to 1883 depending on the size of the disc area) that identify the optic disc surface. All the subjects were also examined with the Humphrey perimeter (Program 30-2) and the results were analyzed by Mann-Whitney U-test and Spearman rank correlation coefficient. · Results: The difference in ODSS between the glaucomatous and the normal eyes was statistically significant. No significant correlation was found between age and ODSS. A significant correlation was found between ODSS and mean deviation (MD) and between ODSS and corrected pattern standard deviation (CPSD). In the glaucoma group there were significant correlations between ODSS and the perimetric indices MD and CPSD; no correlations were found in the normal group. · Conclusion: The ability of ODSS to reflect the level of visual field change in glaucomatous eyes appears to be rather limited, even if statistically significant. This fact does not limit the clinical usefulness of ODSS as a diagnostic parameter in consequence of its strong correlations with the other morphometric parameters and its high sensitivity and specificity in separating normal from glaucomatous eyes.

A comparative study of computerised visual field testing and optic disc morphometric parameters in the follow-up of primary open angle glaucoma

Purpose To evaluate the correlation between computerised visual field testing and optic disc morphometric parameters (rim area, rim/ disc area ratio, cup/disc area ratio and optic disc surface smoothness (ODSS)) in the follow-up of a group of patients affected by primary open angle glaucoma (POAG).Methods Reliable automated perimetry (Humphrey 640 VFA, central 30-2 threshold program) was performed at T0 (the enrolment time), T1 (after 6 ± 1 months;range 5-7 months), T2 (12 ± 1 months), T3 (18 ± 1 months), and T4 (the end of the follow-up period: 24 ± 2 months) in one eye randomly chosen from each of 30 POAG patients. Computerised optic disc analysis (IMAGEnet X Rev-3-51b, Topcon Europe, The Netherlands) was performed at T0 and T4. To evaluate the correlation between morphometric parameters and computerised visual field testing, the stability or worsening of visual field test was evaluated by means of ‘Mean Deviation linear regression analysis’ (STATPAC 2 software); that of morphometric parameters was studied using their coefficients of variation. A rank of ′0′ was assigned to stability and a rank of ″1″ to worsening. The Spearman rank correlation coefficient was used to evaluate statistically the correlations between visual field analysis and morphometric parameters. Furthermore kappa statistic was used to evaluate the agreement of morphometric parameter changes with visual field progression analysis.Results According to the MD slope regression analysis, in 18 patients the visual fields were stable while in 12 they were worsening during the follow-up period. In 86.65% of patients (n = 26) the morphometric parameter ODSS and visual field analysis were concordant (p <0.0001). In 80% of patients (n = 24) the cup/ disc area ratio and visual field analysis were concordant (p < 0.001). The other morphometric parameters (rim area, rim/disc area ratio) were less correlated with visual field analysis than ODSS (p < 0.05). The agreement of visual field analysis with all the morphometric parameters was good (kappa = 0.690, 95% confidence interval (CI) of kappa = 0.589-0.790). The agreement of visual field analysis with ODSS and cup/disc area (kappa = 0.688;95% CI = 0.511-0.864) was better than the agreement of visual field analysis with rim area and rim/disc area ratio (kappa = 0.438;95% CI = 0.260-0.655).Conclusion Analysis of the progression of visual field damage and optic nerve head morphometric parameters should both be taken into account in glaucoma follow-up. Among the morphometric parameters evaluated by means of Topcon IMAGEnet, ODSS and (to a lesser extent) the cup/disc ratio should have the greatest weight.