The effect of cumulative energy in repeated subliminal transscleral cyclophotocoagulation: a retrospective study.

BACKGROUND: The long-term safety and efficacy of repeated applications of subliminal transscleral cyclophotocoagulation (SL-TSCPC) with a focus on cumulative energy was evaluated in glaucoma patients. METHODS: In this retrospective, multicentric study the data of a total of 82 eyes with various causes of glaucoma that were treated with a single or multiple applications of SL-TSCPC were collected. Treatments were performed under general or local anesthesia with an 810 nm diode laser. Power was 2000 mW; duty cycle, 31.3%; total treatment duration, 80-320 s; equaling a total energy of 50-200 J per treatment session. Fifty-five eyes (55 patients) presented for all follow-ups, and these eyes were selected for further statistical analysis. The mean age was 60.0 ± 17.1 years, and 22 (40%) of the patients were female. Intraocular pressure (IOP) and dependence on further glaucoma medication were evaluated at 12 months following the initial treatment. RESULTS: Eyes underwent 1 or 2 consecutive SL-TSCPC treatments. Median (min-max) baseline IOP of 34 (13-69) decreased to 21.5 (7-61), 22 (8-68), 20 (9-68), and 19.5 (3-60) mmHg at the 1, 3, 6, and 12-month postoperative timepoints respectively. The mean (± SD) IOP decrease at 12 months was 26 ± 27%, 39 ± 32%, and 49 ± 33% in the low (below 120 J, n = 18), medium (120-200 J, n = 24), and high (above 200 J, n = 13) cumulative energy groups respectively. At the 12-month timepoint, oral carbonic anhydrase use was discontinued in ¾ of the cases. CONCLUSIONS: It was found that the repeated application of SL-TSCPC safely and efficiently decreases IOP in a Caucasian population with heterogenous causes of glaucoma, eyes with silicone oil responded to a greater extent. Inclusion of cumulative energy scales may contribute to better addressing repeated procedures in a standardized fashion.

Lid-parallel conjunctival folds (LIPCOF) and dry eye: a multicentre study.

AIMS: The study was designed to test the clinical application of the grading of lid-parallel conjunctival folds (LIPCOF) as a diagnostic test for dry eye. METHODS: At 12 centres in 11 countries, 272 eyes of 272 dry eye patients (75 men, 197 women) were examined. Their mean age was 52.7±16.2 years. The LIPCOF were graded according to the method of Höh et al. The tear film break-up time (BUT) was measured, and fluorescein staining and the Schirmer 1 test were performed. The subjective symptoms were evaluated by 16 questions. RESULTS: The LIPCOF score demonstrated significant positive correlations with age, dry eye disease severity and fluorescein staining (r>0.2, p<0.001), and negative correlations with BUT and results of the Schirmer 1 test (r<-0.2, p<0.001). The LIPCOF score exhibited a significant correlation with the overall subjective symptoms (r=0.250, p<0.001). The sensitivity and specificity of LIPCOF grading for discriminating between normal and dry eyes were best with the cut-off between LIPCOF degrees 1 and 2. CONCLUSIONS: The displayed medium sensitivity and specificity, and good positive predictive value of the LIPCOF test support the use of LIPCOF grading as a simple, quick and non-invasive dry eye screening tool.

Tear film function in patients with seasonal allergic conjunctivitis outside the pollen season.

BACKGROUND: Seasonal allergic conjunctivitis can manifest itself through tear film instability and symptoms of eye discomfort during the pollen season. This study investigated whether seasonal allergic inflammation defines tear film instability outside the season. METHODS: Twenty-three control subjects and 13 ragweed-allergic patients were involved (21 female, 15 male; mean age 26.6 ± 5.4 years). Outside the pollen season, subjective ocular symptoms, non-invasive tear film break-up time, lower tear meniscus height and the tear lipid layer's interference pattern grade were recorded. C3a complement activation level was also measured in collected tear samples. RESULTS: Non-invasive tear film break-up time, lower tear meniscus height, C3a complement activation level and the incidence of the different grades of tear lipid pattern did not differ significantly in the two examined groups (p ≥ 0.223). The mean eye symptom score outside the season was greater in the allergic group, but the difference was not significant (p = 0.062). The C3a complement activation level showed a significant and inverse correlation with the lipid layer grade (r = -0.343, p = 0.017). Among the participants with thinner tear lipid layers, the complement activation in the tear samples was higher than among those patients with normal tear lipid layers. CONCLUSION: Seasonal allergic inflammation did not cause permanent tear film instability and eye symptoms were not observed outside the pollen season.

Increased tear osmolarity in patients with severe cases of conjunctivochalasis.

PURPOSE: To evaluate and compare tear osmolarity in different grades of conjunctivochalasis. PATIENTS AND METHODS: Forty subjects divided into four groups based on grading of conjunctivochalasis by lid-paralell conjunctival fold (LIPCOF) test and tear osmolarity evaluated by TearLab osmometer. Schirmer test, tear film break up time (BUT) and vital staining were also performed. RESULTS: Patients with mild and moderate conjunctivochalasis showed similar tear osmolarity to normal subjects. A significant increase (P < 0.008) of osmolarity was found in patients with severe conjunctivochalasis. A significant increase of osmolarity was found in patients with abnormal BUT (P = 0.018) and in patients with positive lissamine-green staining (P = 0.023). No association could be elicited when results of osmolarity were compared to those of Schirmer test or when compared those of fluorescein staining to osmolarity, respectively. CONCLUSION: Hyperosmolarity of tear was reported as a fact of ocular surface inflammation. While in mild and moderate conjunctivochalasis tear osmolarity was similar to normal controls, increased osmolarity can refer to the presence of ocular surface inflammation in these patients with severe conjunctivochalasis.

OCT Imaging of lid-parallel conjunctival folds in soft contact lens wearers.

PURPOSE: To visualize, using Fourier-domain optical coherence tomography (FD-OCT), the alterations in lid-parallel conjunctival fold (LIPCOF) morphology in eyes with contact lenses and after their removal. METHODS: One randomly selected eye of each of 24 volunteers with normal ocular surface status was examined using FD-OCT. The study group included 18 female and 6 male subjects, with a mean age of 28.9 years (range, 18-50 years). The presence, height, and number of conjunctival folds and the tear meniscus area were evaluated by FD-OCT, and the difference between "before and after lens removal" were analyzed by the Wilcoxon signed-rank test. To determine the coverage of the folds, the OCT-LIPCOF grading system was applied. Visualization of the folds was compared on linear and raster scans. The Spearman rank test was applied for correlations (SPSS 16.0; SPSS Inc., Chicago, MI). RESULTS: OCT scans were able to visualize and objectively describe the LIPCOF and its relation to the tear film in contact lens wearers. Raster scanning provided more information about the folds, but the measurements were easier to carry out on the single line scans. After removal of the contact lens, the height of the conjunctival folds significantly decreased (p < 0.001), and the tear meniscus area significantly increased (p = 0.017). The number of LIPCOF did not change (p = 0.971), but LIPCOF coverage by the tear film increased after lens' removal and resulted in changes in the OCT-LIPCOF grading (p < 0.001). CONCLUSIONS: FD-OCT could be a quick, non-invasive, quantitative method for the imaging of LIPCOF in contact lens patients. When grading LIPCOF, the mechanical forces of the lens and the tear meniscus changes caused by the lens should be taken into account as these factors influence results. Follow-up of the patients using the same methods is suggested with or without contact lenses.

Imaging lid-parallel conjunctival folds with OCT and comparing its grading with the slit lamp classification in dry eye patients and normal subjects.

PURPOSE: To visualize and describe the morphologic appearance of lid-parallel conjunctival folds (LIPCOFs) by using optical coherence tomography (OCT) and to relate it to dry eye signs and symptoms. METHODS: The LIPCOF grade, noninvasive tear film breakup time (NIBUT), lipid layer interference pattern, and dry eye symptoms were recorded in 17 normal subjects and 33 patients with dry eye. LIPCOFs were evaluated with a slit lamp and visualized by OCT. Three different algorithms for OCT were developed to grade LIPCOFs according to tear meniscus height or the covering tear film on the folds. RESULTS: The three OCT methods showed significant correlation with the slit lamp method (r = 0.470-0.473, P < 0.01). The OCT LIPCOF imaging methods were independent of NIBUT. The Dry Eye Questionnaire (DEQ) scores correlated with the height of the folds and the absence of tear film coverage of the folds (r = 0.574, P < 0.001 and r = -0.527, P < 0.001, respectively). The OCT LIPCOF grades correlated with the DEQ scores (r = 0.494, P < 0.001 and r = 0.310, P = 0.029, respectively). The slit lamp grade did not correlate with the DEQ scores in the whole population, but did in the normal group (r = 0.458, P = 0.024). The OCT LIPCOF grades showed inverse correlation with lipid pattern in the normal group (r = -0.422-0.481, P = 0.05); however, this association disappeared in the dry eye group. CONCLUSIONS: OCT enabled a noninvasive, high-resolution method of imaging, evaluating, and classifying LIPCOFs. These new classifications correlated well with the slit lamp grade and the DEQ scores, promising a new, more objective evaluation of dry eye.

Comparison of Tearscope-plus versus slit lamp measurements of inferior tear meniscus height in normal individuals.

PURPOSE: To measure the lower tear meniscus height (LTMH) with image by Tearscope and using slit-lamp biomicroscopy with or without fluorescein staining. METHODS: The lower tear meniscus height was measured in 31 eyes of 31 healthy volunteers (mean age 31.29 years; SD 4.83) with Tearscope and slit lamp with and without fluorescein staining. The mean values of LTMH were measured with different methods and the repeatability of the measurements was statistically analyzed. Measurement of fluorescein tear film break up time (FBUT) and Schirmer test were also performed. RESULTS: The mean value of LTMH was 0.21 mm (SD 0.07) with Tearscope, 0.20 mm (SD 0.06) with slit lamp without fluorescein staining, and 0.23 mm (SD 0.07) with fluorescein staining. There was no significant difference among the mean values of LTMH with these 3 different measurement methods. Based on the random effect analysis of variance (p=0.05), the measurements were more repeatable with Tearscope-plus than with the other 2 methods. No correlation was found between the LTMH and the results of Schirmer test or FBUT. CONCLUSIONS: The LTMH could be reliably measured with slit-lamp biomicroscopy without staining, but the measurements were more repeatable with Tearscope.

Kinetic analysis of topographical parameters and interference pattern of tear lipid layer in normal subjects.

PURPOSE: To investigate the post-blink changes of the topographical regularity indices, the corneal wavefront aberrations and the tear lipid layer's interference pattern, and analyze the relationship between these parameters' changes. METHODS: Sequential topographical measurements were recorded on 23 normal participants. The surface regularity index (SRI), surface asymmetry index (SAI), corneal total higher order aberrations (HOA) root mean square (RMS), Coma RMS and Spherical RMS were calculated from the topographical measurement. The incidence of the type 1 (with an initial decrease after blink) alteration trend, and the times to the initial minimum were determined in every parameter. The movement of the tear lipid layer's interference pattern was recorded, and the spreading time of the lipid layer was measured subjectively by three independent observers. RESULTS: The incidence of the type 1 SRI trend (82%) was the most common among those measured. The average time to the type 1 SRI trends' minimum was 4.05 ± 1.46 s. There was no correlation between the time to the minimum of type 1 trends of the topographical indices, the HOA, Coma and Spherical RMS. The mean lipid layer spreading time was 5.09 ± 1.90 s. We found weak but significant correlation between the times to the minimum of type 1 SRI trends and the lipid spreading time (r = 0.540, p = 0.021).The minimum of the SRI index occurred before the stoppage of superficial lipid layer's motion. CONCLUSION: Relatively long lipid layer spreading time was observed suggesting that the tear film build-up process did not finish completely at the end of the initial rapid tear film alteration phase. The detected initial decrease of the SRI after blink related to the post-blink tear film motion. This initial pattern is characteristic of the majority of the normal population in spite of the post-blink alteration pattern of the topographical SAI or corneal aberrations. The SRI seems to be the most useful indirect topographical parameter of the tear film dynamics.

Variability of higher order wavefront aberrations after blinks.

PURPOSE: To investigate the rapid alterations in value and fluctuation of ocular wavefront aberrations during the interblink interval. METHODS: Forty-two volunteers were examined with a WASCA Wavefront Analyzer (Carl Zeiss Meditec AG) using modified software. For each subject, 150 images (about 6 frames/second) were registered during an interblink period. The outcome measures were spherical and cylindrical refraction and root-mean-square (RMS) values for spherical, coma, and total higher order aberrations. Fifth order polynomials were fitted to the data and the fluctuation trends of the parameters were determined. We calculated the prevalence of the trends with an early local minimum (type 1). The tear production status (Schirmer test) and tear film break-up time (BUT) were also measured. RESULTS: Fluctuation trends with an early minimum (type 1) were significantly more frequent than trends with an early local maximum (type 2) for total higher order aberrations RMS (P=.036). The incidence of type 1 fluctuation trends was significantly greater for coma and total higher order aberrations RMS (P=.041 and P=.003, respectively) in subjects with normal results in the BUT or Schirmer test than in those with abnormal results. In the normal subjects, the first minimum of type 1 RMS fluctuation trends occurred, on average, between 3.8 and 5.1 seconds after blink. CONCLUSIONS: We suggest that wavefront aberrations can be measured most accurately at the time after blink when they exhibit a decreased degree of dispersion. We recommend that a snapshot of wavefront measurements be made 3 to 5 seconds after blink.