Study of the hormetic effect of disinfectants chlorhexidine, povidone iodine and benzalkonium chloride.

The study of the dose-response relationship of disinfectants is of great importance in treating infection, the objective being to use concentrations above the minimal bactericidal concentration (MBC). Below these concentrations, the bacteriostatic or bactericidal effect may be insufficient. Moreover, at low concentrations, a hormetic effect may be observed, producing a stimulation of growth instead of inhibitory action. Hormesis is not well known in the context of antimicrobial substances. This study investigates the possible existence of a hormetic effect in three commonly used antiseptics-chlorhexidine digluconate, povidone iodine and benzalkonium chloride-on strains of reference of Staphylococcus aureus and Pseudomonas aeruginosa. Growth curves were determined for different concentrations of the disinfectants. The variables studied-concentration of disinfectant, instantaneous growth rate and number of generations-were analysed using linear, quadratic and cubic models to adjust for the variables. The three disinfectants tested show a significant hormetic effect with P. aeruginosa and a less significant effect with S. aureus. These findings point to a dose-response effect that is not linear at low concentrations, while hormetic effects observed at some low concentrations result in greater bacterial growth. In infected wounds, materials or surfaces where microorganisms may occupy zones of difficult access for a disinfectant, the hormetic effect may have important consequences.

Agreement between central corneal thickness measured using Pentacam, ultrasound pachymetry, specular microscopy and optic biometer Lenstar LS 900 and the influence of intraocular pressure.

PURPOSE: To compare central corneal thickness (CCT) values obtained by Lenstar (LE), Pentacam (PC), specular microscopy (SM) and ultrasound pachymetry (UP) in healthy corneas and study their influence on intraocular pressure (IOP) readings determined by Goldmann applanation tonometry (GAT). METHODS: CCT was measured in 76 healthy subjects by LE, PC, SM and UP. We established Lin's concordance correlation coefficient (ρ-C) between different techniques. The influence of CCT on GAT was established through univariate linear regression models, IOP being the dependent variable. RESULTS: The highest ρ-C was found between LE and SM at 0.94 (95% CI: 0.91-0.96) and between LE and UP at 0.95 (95% CI: 0.94-0.97). IOP readings showed less variability when CCT was determined using LE (7.7%, B = 0.16; 95% CI: 0.004-0.28). CONCLUSIONS: Although CCT values obtained with UP, PC, SM and LE show good correlation, these methods are not completely interchangeable. The amount of IOP variation differs when CCT is determined using LE or SM.

Detection and characterisation of visual field defects using Octopus perimetry in congenital glaucoma.

PURPOSE: To detect and characterise visual field (VF) defects using static Octopus perimetry in patients with primary congenital glaucoma (PCG) and to determine VF quality and time duration. MATERIAL AND METHODS: Eighty-eight eyes of 70 patients diagnosed with PCG were included. Assessments were performed using an Octopus 900 and each eye was assessed with the tendency-oriented perimetry (G-TOP) algorithm. Quantitative VF data were collected: quality data (false positive and negative response, and time duration) and results of mean deviation (MD) and square root of loss variance (sLV). Qualitative data were collected: the presence of diffuse and localized defects, the affected hemifield and grade of defects using the Aulhorn and Karmeyer classification. Correlations between perimetric results and clinical variables were analysed. RESULTS: Median age was 11 (8-17) years. 65.9% (58/88) of PCG eyes showed VF defects. Diffuse defects were observed in 10/58 eyes (16.94%) (mean MD = 23.92 [SD: 2.52]) dB) and localized defects in 48/58 eyes (82.75%). The most frequent defect was spot-like/stroke-like/incipient paracentral scotoma (n = 15), nasal step (n = 8), adding arcuate defect (n = 2), half ring-shaped (n = 13) and concentric defect with a central island (n = 9). And the most frequent affected visual hemifield was inferior hemifield. Mean test duration was 2 min 12 s (SD: 21.6 s). MD and sLV values were correlated with best corrected visual acuity (BCVA), cup to disc ratio and number of antiglaucoma surgeries (all P < .001). CONCLUSION: A high number of diffuse and localized defects were identified using Octopus perimetry in PCG patients. The most frequent defect was paracentral scotoma and inferior hemifield was the most affected.

Analysis of the influence of corneal properties and densitometry on applanation and rebound tonometry in primary open angle glaucoma.

PURPOSE: To evaluate the influence of corneal densitometry on portable applanation (Perkins) and rebound (iCare ic100 and PRO) tonometry. A secondary goal was to assess if there was a relationship between various corneal properties and the severity of primary open angle glaucoma (POAG). MATERIAL AND METHODS: Seventy-five eyes of 75 patients with primary open angle glaucoma were studied, divided by severity into 3 groups: 25 mild, 25 moderate and 25 advanced. Intraocular pressure (IOP) was measured 3 times in each participant with a Perkins applanation tonometer (PAT), a handheld version of the Goldman applanation tonometer (GAT), an iCare PRO and an iCare ic100. Mean values were then calculated. Corneal topography with the Pentacam HR (Oculus, Wetzlar, Germany) was also performed in all individuals. RESULTS: Mean age and sex were comparable in all groups, as were densitometry values (P>0.05). The mean visual field defect (MD) was 2.85 (±1.23) dB in the mild glaucoma group, 8.26 (±1.90) dB in the moderate group and 15.66 (±3.46) dB in the advanced group. Three multivariate regression analyses were performed. The first and second calculations assessed the effect of IOP obtained with iCare ic100 and PAT as dependent variables with age, sex, CCT and mean keratometry (Km) within the glaucoma subgroups and the global sample. The third analysis was carried out to assess the relationship between corneal densitometry as the dependant variable and the aforementioned corneal parameters among the glaucoma groups. In the first multivariate regression analysis, a statistically significant correlation was found between ic100 rebound tonometry and CCT in the POAG global sample (coef. 0.117; IC [-0.21-(-0.01)]; P=0.025). No statistically significant correlation was found in the subgroup analyses. In the second multivariate analysis, no significant correlation was found between PAT and CCT, Km, age or sex (P>0.05). In the third analysis, densitometry was correlated with age in all glaucoma subgroups (P<0.001) and with CCT in the moderate glaucoma subgroup (coef. -0.037; IC [-0.67-(-0.01)]; P=0.021). Tonometry appeared to be minimally influenced by corneal densitometry, with a mild positive linear correlation seen (R=0.03). IOP values were similar with 3 of the tonometers: PAT 16.07 (±3.18) mmHg, PRO 16.27 (±3.42) mmHg and ic100 15.17 (±4.28) mmHg. There was, however, a significant underestimation of IOP with ic100 (-0.89mmHg) compared to PAT (P=0.007). CONCLUSION: Corneal densitometry did not show significant differences between glaucoma severity groups. A positive correlation was seen with CCT and both corneal densitometry and age. No correlation was found with keratometry or severity of glaucoma. The influence of corneal densitometry on IOP measurements appears weak, with little clinical relevance identified.

Diagnostic ability of vessel density of the optic nerve head and macula versus structural parameters with optical coherence tomography in pseudoexfoliative glaucoma.

PURPOSE: To evaluate the diagnostic ability of the vessel density (VD) of the optic nerve head (ONH) and the macula on optical coherence tomography (OCT) angiography and the retinal nerve layer thickness (RNFL) thickness and the macular ganglion cell complex (GCC) thickness on OCT in patients with pseudoexfoliative glaucoma (PXG). METHODS: Cross-sectional study including PXG patients and healthy controls. Demographic and clinical data were noted for all participants. Optical coherence tomography (OCT) and OCT angiography (OCTA) images of the ONH and macular area were obtained with the RS-3000 Advance OCT (Nidek Co., Gamagori, Japan). The RNFL and GCC thickness of different sectors was provided by the software. Macular VD of the superficial capillary plexus (SCP) and ONH VD of the radial peripapillary capillary plexus (RPCP) were registered. Groups were compared and area under the receiver operating characteristic (AUROC) curves were used to determine the power of discrimination of each parameter. RESULTS: RNFL and GCC thickness and ONH and macular VD were significantly lower in PXG patients compared with healthy controls (all, p<0.05). The best discrimination parameter was the average RNFL thickness (AUROC: 0.928). ONH VD AUROC was better than that of macular VD (AUROC: 0.897 and 0.780, respectively). ONH VD AUROC was comparable to RNFL thickness (p<0.001). CONCLUSIONS: The diagnostic ability of ONH vessel density in PXG appears comparable to that of the structural parameters, RNFL and GCC thickness, obtained with OCT, and may be a valuable tool in clinical practice.

Reliability and agreement analysis among 5 subjective methods of ocular torsion measurement.

OBJECTIVE: To evaluate the reliability in the measurement of ocular torsion and the agreement of the following subjective methods: double Maddox test, synoptophore, Gracis torsionometer, Harms screen and Awaya cyclodeviation test. METHOD: Patients with vertical strabismus acquired in adulthood were recruited and ocular torsion was measured with the 5 methods described on three occasions. As a gold standard test does not exist, the one that obtained the best repeatability data was chosen as the reference test. RESULTS: 25 patients were included in the study. The repeatability of each test was studied: double Maddox test (ICC = 0.783, CV = 29.33%), synoptophore (ICC = 0.976, CV = 6.71%), Gracis torsionometer (ICC = 0.937, CV = 20.10%), Harms screen (ICC = 0.962, CV = 11.86%) and Awaya test (ICC = 0.987, CV = 52.58%). The reference test to compare the agreement was the synoptophore. Statistically significant differences were found when comparing the ocular torsion ranges between the synoptophore and the Gracis torsionometer (p = 0.008) and between the synoptophore and the Awaya test (p = 0.02). CONCLUSIONS: The double Maddox test, the synoptophore, the Gracis torsionometer, and the Harms screen are reliable methods with good reproducibility indices. Among them, the synoptophore is the most consistent method. The Awaya test did not show good reliability. The bilateral Maddox test, the Gracis torsionometer, and the Harms screen were methods with good agreement with the synoptophore, which was determined as the reference test. The Awaya test did not show good agreement with the synoptophore.

Posterior chamber implantation of a Preserflo Microshunt in a patient with a compromised endothelium.

The objective of the present case is to describe a variation in the Preserflo Microshunt surgical technique, placing it in the posterior chamber to minimise the risk of endothelial cell loss in cases with a compromised endothelium. The patient was a 72-year-old pseudophakic woman, with granular dystrophy and a primary diagnosis of open-angle glaucoma presenting with a progressive visual field defect and an IOP of 26 mmHg with maximal medical therapy. The cornea had incipient stromal folds with an endothelial count of 700 cells/mm2. A Preserflo Microshunt was implanted in the posterior chamber to minimise the possibility of further damage to the corneal endothelium. Six months after surgery, the implant remains functional. The IOP is 9 mmHg without medications. As far as we know, this is the first Preserflo implanted in the posterior chamber described in the literature.

Myopia progression and axial elongation in Spanish children: Efficacy of atropine 0.01% eye-drops.

PURPOSE: To assess myopia progression in Spanish children and whether treatment with low-dose atropine eye drops delays myopia progression and axial elongation. METHODS: 339 eyes of 339 Caucasian patients with myopia, aged 5 to 11 years, were examined. Participants were randomized to a treatment arm, receiving one atropine (0.01%) eye drop/day for two, and an untreated control arm. At the baseline and 2-year follow-up visits, we recorded: spherical equivalent (SE), axial length (AL), mean keratometry (Mean-K) and anterior chamber depth (ACD). We also examined the rate of children with higher myopia progression (change in SE >1 D/2 years) and identified risk factors for progression. RESULTS: In 339 eyes of the 339 children (age=7.61; SD 1.70; range 5-11 years), the mean baseline SE was-2.15 (SD 0.62) D, and AL was 24.24 (SD 0.79) mm. After 2 years, higher increases occurred in all variables except ACD in the untreated group vs. the atropine group, respectively: SE (-0.51 (SD 0.39) D vs. -0.76 (SD 0.37) D, P<0.001), AL (0.20 (SD 0.20) mm vs. 0.37 (SD 0.27) mm, P<0.001) and Mean-K (0.01 (0.28) D vs. 0.09 (0.32) D, P=0.018). Myopia progression was reduced by 32% in the treatment group. There were more progressors >1D/2y in the control group: 62/168 (36.9%) vs. 35/171 (20.5%) (P<0.001). Atropine was identified as a protective factor against myopia progression (B=1.12; 95% CI= 0.98-1.27; P=<0.001). CONCLUSION: Spanish children showed a low rate of myopia progression. Atropine 0.01% showed a significant effect in slowing the progression of both refractive error and axial elongation.

Comparision of intraocular pressure measured using the new icare 200™ rebound tonometer and the Perkins™ applanation tonometer in healthy subjects and in patients with primary congenital glaucoma. / Comparación entre el tonómetro de rebote IC200 y el tonómetro de aplanación Perkins en sujetos sanos y pacientes con glaucoma congénito.

OBJECTIVE: To compare intraocular pressure (IOP) measurements obtained using the Icare 200™ (IC200) rebound tonometer and the hand-held version of the Goldmann Applanation Tonometer (Perkins™ tonometer, GAT) in patients with primary congenital glaucoma (PCG) and in healthy subjects. MATERIAL AND METHODS: A total of 42 eyes of healthy subjects (G1) and 40 patients with PCG (G2) were analysed. The following clinical data were collected: gender, age, Cup/Disc ratio, central corneal thickness (CCT). IOP was determined in the examination room using the IC200 and GAT tonometers, in the same order. Agreement between both tonometers was determined using the intraclass correlation coefficient (ICC) and Bland-Altman plot. A linear regression analysis was used to establish the IOP was affected by the studied variables. RESULTS: Mean IOP between both tonometers (IC200 minus GAT) was: G1=15.91 (2.57) mmHg vs. 15.06 (2.12) mmHg (mean difference, MD=0.84 (0.50) mmHg; P<.101) and G2=20.10 (6.37) vs.19.12 (5.62) (MD=0.98 (1.36); P=.474). Excellent agreement was found between IC200 and GAT in both groups (ICC=G1: 0.875 (95% CI; 0.768-0.933; P<.001); G2: 0.924 (95% CI; 0.852-0.961; P<.001), and there was a statistically significant correlation between the IOP difference measured with IC200 and GAT and CCT in G1 (B=0.021; 95% CI; 0.005-0.037; P=.008), but was not statistically significant in G2. CONCLUSION: There was excellent agreement between the IC200 and GAT tonometers, both in healthy subjects and PCG, with a trend to overestimate IOP when measured with IC200. There was no influence by CCT on IOP measurements in patients with PGC.

Reproducibility of SD-OCT inner macular layer thickness measurements in children with primary congenital glaucoma.

PURPOSE: To examine the reproducibility of spectral domain optical coherence tomography (SD-OCT) segmented ganglion cell complex and circumpapillary retinal nerve fiber layer (cpRNFL) measurements in children with primary congenital glaucoma (PCG) in comparison with healthy children. METHODS: 12 children with PCG (G1) and 24 healthy children (G2) were recruited. The following SD-OCT measurements (Spectralis, Heidelberg Engineering) were made in one eye per child: total macular thickness (MT), thicknesses in several subfields and volumes of the three inner macular layers, macular retinal nerve fiber layer (mRNFL), ganglion cell layer (GCL), and inner plexiform layer (IPL) and cpRNFL thickness. In a single day, an expert operator obtained 3 circumpapillary and 3 macular measurements in each participant to determine intraoperator variability. Intraoperator repeatability was defined by the coefficient of variation (CoV) and intraclass correlation (ICC). RESULTS: ICC was excellent in both groups for cpRNFL measurements (G1 ICC=0.950 and G2 ICC=0.995) and for MT was excellent in G1 (ICC=0.957) and moderate in G2 (ICC=552). For the inner macular layer measurements, all ICCs were better in PCG group (mRNFL-ICC: 0.915 vs. 0.765; ICC-GCL: 0.584 vs. 0.263 and ICC-IPL: 0.979 vs. 0.742; G1 and G2 respectively). Greater CoV were recorded for macular measurements (from 0.71% to 9.82%) compared to cpRNFL measurements (from 0.52% to 1.50%). CONCLUSION: In children with PCG, Spectralis SD-OCT showed excellent intrasession repeatability for cpRNFL, MT, mRNFL and IPL measurements and moderated for GCL measurements. For all macular measurements, ICC were higher in children with PCG than healthy children.

Satisfaction with strabismus surgery based on the opinion of expert surgeons. / Satisfacción de la cirugía de estrabismo basada en la opinión de cirujanos expertos.

PURPOSE: To assess the perception of strabismus surgeons in Spain regarding patient satisfaction after surgery, by analysing the types of strabismus with the most satisfied patients, as well as the causes of dissatisfaction. METHODS: A survey was carried out among the members of the Spanish Strabology Society who were over 50 years of age, active in Spain, with more than 20 years of surgical experience, and whose main surgical activity was strabismus. The questionnaire consisted of 18 questions about the perception of patient satisfaction according to the type of strabismus, patient age, as well as the most frequent cause of dissatisfaction after surgery. RESULTS: The questionnaires were completed by a total of 29 surgeons, with a mean of 31 years of surgical experience. The most frequent cause of perceived dissatisfaction was residual strabismus. No differences were found in the satisfaction index between children and adults. The surgery that was considered to produce greater satisfaction was endotropia, followed by decompensated 4th nerve palsy, and exotropia, while 3rd nerve palsy was the cause of the most dissatisfaction. CONCLUSIONS: According to strabismus surgeons, endotropia is the most satisfactory surgery for the patient, followed by exotropia, vertical strabismus, and traumatic paralysis of the 4th cranial nerve.

Management of strabismus related to infantile glaucoma: Case series.

OBJECTIVE: To evaluate the different modalities of treatment of the strabismus related to infantile glaucoma, its complications, and results. METHODS: The clinical history of 7 patients with infantile glaucoma which required strabismus surgical treatment were analyzed. Age at onset of glaucoma, type of glaucoma, glaucoma surgeries, type of strabismus, strabismus surgical treatment and postoperative results were studied. RESULTS: Four patients required strabismus surgery, two were treated with botulinum toxin and one required both. Primary congenital glaucoma was the most common (71,42%), 14,28% had an anterior segment dysgenesis and 14,28% had secondary glaucoma. Regarding strabismus, 4 patients had exotropia and 3 had esotropia. The main difficulty involved the management of the conjunctiva and the filtering blebs. CONCLUSION: Strabismus is a frequent complication in infantile glaucoma. The management of these patients should be individualized. In our case series, treatment of strabismus improved eye alignment. Surgery should be the mainstay of treatment while preserving the conjunctiva and interfere the less with glaucoma surgeries. Botulinum toxin is a reasonable option when conservative treatment is needed.

Corneal densitometry and topography in patients with primary congenital glaucoma.

OBJECTIVE: To compare corneal densitometry and topography variables in patients with primary congenital glaucoma (PCG) and healthy subjects. MATERIAL AND METHODS: Cross sectional study, consecutive recruitment with gender- and age-matched control group. Forty eyes of 40 patients in each group were studied with Pentacam corneal topography. The variables compared between the two groups were: intraocular pressure (IOP), visual acuity (VA) and Pentacam (Oculus, Wetzlar, Germany) corneal topography measurements: mean and maximum keratometry (Km, Kmax), cylinder (Cyl), anterior elevation apex (AEA), central anterior elevation (CAE), maximum anterior elevation (MAE), posterior elevation apex (PEA), central posterior elevation (CPE), maximum posterior elevation (MPE), pachymetry and anterior, mid-stromal and posterior corneal densitometry in the 0-2mm, 2-6mm, 6-10mm zones. RESULTS: Significant differences between patients and healthy controls were detected in the topographic variables MAE (P=0.002) and MPE (P<0.001), and in all the densitometry variables (anterior, mid-stromal, posterior for the 0-2mm, 2-6mm and 6-10mm zones) (P<0.001 each). In the PCG group, negative correlation was observed between VA and total densitometry (r=-0.49; P=0.004). CONCLUSION: Patients with PCG and healthy subjects display differences in corneal densitometry and topographic measurements. PCG patients show greater corneal density with an inverse relationship between visual acuity and higher elevation (anterior and posterior values).

Scheie's line as a first sign of pigment dispersion syndrome. / Línea de Scheie como primer signo de síndrome de dispersión pigmentaria.

A 50 year old woman was diagnosed with pigment dispersion syndrome (PDS) in the right eye and pigmentary glaucoma in the left eye in a routine medical examination. A line of pigment was observed in the vitreo-lenticular interface (Scheie's line) of the left eye and with an intraocular pressure of 26mmHg. The Scheie's line (SL) develops by the accumulation of detached iris pigment in PDS and accumulated in the ligament of Wieger that forms the vitreo-lenticular union. The SL is considered a pathognomonic sign of PDS.

The correlation between the thickness of the inner macular layers and the mean deviation of the visual field in children with primary congenital glaucoma. / Correlación entre el grosor de las capas internas de la retina y el defecto medio del campo visual en pacientes con glaucoma congénito primario.

PURPOSE: To analyse the association between the thickness of the circumpapillary retinal nerve fibre layer (cpRNFL) and the thickness of the inner macular layers with the mean deviation of the visual field (MD) in children with primary congenital glaucoma (PCG). MATERIAL AND METHODS: A total of 41 children with PGC were included in the study. They all had a complete ophthalmological examination, including visual acuity, intraocular pressure, funduscopy, Octopus™ visual field, as well as circumpapillar and macular spectral domain optical coherence tomography (SD-OCT). SD-OCT with automated segmentation was used to measure the thicknesses and volumes of the macular retinal nerve fibre layer (mRNFL), ganglion cell layer (GCL), and inner plexiform layer. RESULTS: The mean age was 11.2±3.86 years, and the mean MD was 8.85±6.76dB. The visual field was classified as normal in 46% of the patients, and 20% of the patients had a concentrical restriction of the visual field. A positive correlation was found between between the cup-to-disc ratio and the MD, r=0.51 (P=.004). The correlation between the MD and the cpRNFL was r=-0.63 (P<.001), and r=-0.69 (P<.001) with the GCL. CONCLUSIONS: Inner macular layers thickness and cpRNFL thickness show a good correlation with the mean deviation of the visual field in children with primary congenital glaucoma.

Quality of life and visual function in children with glaucoma in Spain. / Estudio de la calidad de vida y la función visual en niños con glaucoma en España.

OBJECTIVE: To evaluate the effect of glaucoma on visual function, as well as quality of life in children and quality of life perceived by caregivers in children up to 16 years of age. MATERIAL AND METHODS: An observational and prospective study was designed using the questionnaire GQL-15 (Glaucoma Quality of Life) and conducted on children and caregivers. The questionnaire VFQ-25 (Visual Functioning Questionnaire) was conducted on children. Different variables of the clinical history that could influence the quality of life and visual function were recorded. RESULTS: The study included 24 patients with a mean age of 9.13±3.08 years, and included 3 with unilateral involvement, and 20 diagnosed with primary congenital glaucoma. Parents reported a worse quality of life than children. The result of the GQL-15 survey was 32.3±11.56 points in children and 37.52±14.59 points in caregivers (P=.001). The parameter most related to quality of life and visual function was the mean deviation (MD) of the visual field in the best eye. A statistically significant correlation was found between the result of GQL-15 and the mean deviation of the visual field (children: R=0.63, P<.01, caregivers: R=0.81, P<.001). CONCLUSIONS: Functional loss has an impact on the quality of life and visual function in children with glaucoma, although the quality of life perceived by the caregivers is worse than that perceived by the child.

Charles Bonnet syndrome in a child with congenital glaucoma. / Síndrome de Charles Bonnet en un niño con glaucoma congénito.

CASE REPORT: The case is presented of a 12 year-old boy with congenital glaucoma and low visual acuity diagnosed with Charles Bonnet syndrome. This consisted of the acute onset of complex, repetitive, persistent, and with visual hallucinations (people, brooms and coffeemakers) of self-limited evolution without treatment. The patient was diagnosed with congenital glaucoma at 3 years of age, and subjected to a trabeculectomy in right eye, and trabeculectomy and keratoplasty in his left eye. DISCUSSION: Charles Bonnet syndrome symptoms have been described in adults, but their presence in children is poorly reflected in literature, with unknown characteristics and prevalence.

Topical brinzolamide in congenital nystagmus: A retrospective study. / Brinzolamida tópica en el nistagmo congénito: Estudio retrospectivo.

OBJECTIVE: To evaluate the effect of treatment with topical brinzolamide on visual acuity and nystagmus intensity in patients with congenital nystagmus. MATERIAL AND METHODS: A retrospective study was designed in which the clinical records of 14 patients with congenital nystagmus were reviewed. All patients underwent a complete ophthalmological examination and a Perea video-oculography (VOG) before, and three days after, initiation of treatment with topical brinzolamide (Azopt). Five expert researchers evaluated the intensity of nystagmus by video before and after treatment. Finally, the subjective improvement of the patients was recorded. RESULTS: Statistically significant differences were found in pre- and post-treatment binocular near visual acuity. A slight increase in the frequency of nystagmus was found, which was statistically significant with the horizontal gaze to the left and with the gaze downwards (P=.04, P=.03, respectively). The kappa index concordance between the researchers evaluating the intensity of nystagmus was 0.014. Only two of the patients noticed improvement in visual acuity, and one patient noticed improvement in the aesthetic aspect. CONCLUSIONS: In spite of an improvement in nystagmus, it was slight, not cosmetically appreciable by patients in most cases, and was not related to a significant improvement in visual acuity or in patient quality of life. Further studies are needed to evaluate the effects of topical brinzolamide, and to establish potential therapeutic indications in nystagmus.

Agreement between intraoperative measurements and optical coherence tomography of the limbus-insertion distance of the extraocular muscles. / Concordancia de la distancia desde la inserción hasta el limbo de los músculos rectos entre la medida intraoperatoria y con tomografía de coherencia óptica.

OBJECTIVE: To assess the agreement between intraoperative measurements of the limbus-insertion distance of the extraocular muscles with those measured by spectral domain optical coherence tomography. METHODS: An analysis was made of a total of 67 muscles of 21 patients with strabismus. The limbus-insertion distance of the horizontal rectus muscles were measured using pre-operative SD-OCT and intra-operatively in 2 ways: 1) direct, after a conjunctival dissection in patients who underwent surgery, or 2) transconjunctival in patients who were treated with botulinum toxin, or in those who were not going to be operated. The intraclass correlation coefficient and Bland-Altman plots were calculated to determine the concordance between the 2 methods. RESULTS: The mean age was 45.9 ±20.9 years (range 16 to 85), with 52% being women. The percentage of identification by direct intraoperative measurement was 95.6% (22/23), by transconjunctival intraoperative measurement 90.9% (40/44), and by OCT 85% (57/67), with 22 muscles finally being analysed for the agreement study between direct intraoperative measurement and OCT measurements, and 35 muscles for the agreement between transconjuctival intraoperative measurement and OCT. The intraclass correlation coefficient showed good agreement with OCT and direct intraoperative measurements (0.931; 95% confidence interval (95% CI): 0.839-0.972; P<.001), and with transconjunctival intraoperative measurements (0.889; 95% CI: 0.790-0.942; P<.001). CONCLUSIONS: The SD-OCT is an effective technique to measure the distance from the insertion of the horizontal rectus muscles to the limbus, with a high agreement with intraoperative measurements being demonstrated.