Forma clínica e fatores de risco associados ao estrabismo na binocularidade visual / Clinical forms and risk factors associated with strabismus in visual binocularity

RESUMO Objetivo: Identificar e analisar fatores de risco associados ao estrabismo, dados oftalmológicos e antecedentes pessoais e familiares. Métodos: Estudo prospectivo, descritivo e analítico realizado com 240 pacientes que consultaram pela primeira vez nos ambulatórios de estrabismo. Foram avaliadas a frequência e associação entre estrabismo, dados de exames oftalmológicos e antecedentes pessoais e familiares para identificação dos fatores de risco. Resultados: Observou-se maior prevalência de estrabismo em mulheres (56,96%) em relação aos homens (43,02%). A faixa etária mais atendida no ambulatório de estrabismo foi composta de crianças até 15 anos de idade (83,54%). Encontrou-se mais esotropia (55,27%) que exotropia (42,20%) e parcela menor de estrabismo vertical isolado (2,53%). A prematuridade foi associada ao estrabismo convergente (p=0,023) e não ao divergente (p=0,086). O diabetes mellitus materno foi associado à esotropia (p=0,024) e exotropia (p=0,036) no filho, mas a hipertensão arterial materna, uso de medicamentos para hipertensão e diabetes durante a gravidez e drogas ilícitas não foram estatisticamente significativos. Pacientes com paralisia cerebral tiveram mais associação com exotropia (p=0,008) que esotropia (p=0,019). Malformações congênitas, consanguinidade entre os pais e traumas oculares não apresentaram associação estatisticamente significativa para o estrabismo. A maioria dos pacientes com estrabismo apresentou boa acuidade visual corrigida e fundoscopia normal. Na análise de proporções a hipermetropia foi mais frequente na esotropia (68,7%). Conclusão: Os fatores de riscos internos e externos podem interferir na formação e desenvolvimento do olho na fase de plasticidade ocular, com prejuízo da binocularidade visual, podendo resultar em estrabismo. Há divergências com relação aos fatores de risco realmente associados e mais estudos são necessários para a identificação.

ABSTRACT Objective: To identify and analyze risk factors associated with strabismus, the eye data and personal and family history. Methods: A prospective, descriptive and analytical study, with 240 patients who consulted for the first time in strabismus clinics. We evaluated the frequency and association between strabismus and data eye examination and personal and family history to identify risk factors. Results: There was a higher prevalence of strabismus in women (56.96%) compared to men (43.02%). The age group most satisfied in strabismus clinic are children up to 15 years of age (83.54%). Met more esotropia (55.27%) than exotropia (42.20%) and lower portion of isolated vertical strabismus (2.53%). Preterm birth was associated with convergent strabismus (p = 0.023) but not the diverging (p = 0.086). Maternal diabetes mellitus was associated with esotropia (p = 0.024) and exotropia (p = 0.036) on the child, but the mother’s high blood pressure, medications for hypertension and diabetes during pregnancy and illicit drugs was not statistically significant. Patients with cerebral palsy association with exotropes had more (p = 0.008) which esotropia (p = 0.019). Congenital malformations, consanguinity between parents and ocular trauma showed no statistically significant association for strabismus. Most patients with strabismus showed good visual acuity, normal fundus. In the analysis of proportions farsightedness was more common in esotropia (68.7%). Conclusions: Internal and external risk factors can interfere in the formation and development of the eye in eye plasticity phase with impaired visual binocularity and may result in strabismus. There are differences with respect to risk factors associated truly and more studies are needed to identify.

Comparison of Postoperative Exodrift after First Unilateral and Second Contralateral Lateral Rectus Recession in Recurrent Exotropia

PURPOSE: To compare postoperative exodrift of the first unilateral lateral rectus (ULR) muscle recession with the exodrift of the second contralateral ULR muscle recession in patients with recurrent small-angle exotropia (XT). METHODS: We evaluated the results of a second ULR muscle recession in 19 patients with recurrent XT with deviation angles under 25 prism diopter (PD), following a first procedure of ULR muscle recession for small-angle XT. Recession of the lateral rectus muscle ranged from 8 to 9 mm. The postoperative motor alignment and degree of exodrift were investigated after the first ULR muscle recession and the second ULR muscle recession in the same patients. RESULTS: Observed differences in postoperative ocular alignment between the first ULR muscle recession and the second ULR muscle recession were statistically significant at follow-up periods of six months (7.84 +/- 4.43 vs. 3.89 +/- 3.47 PD), one year (9.58 +/- 4.97 vs. 5.21 +/- 4.94 PD), and at a final follow-up (21.11 +/- 2.98 vs. 7.52 +/- 4.06 PD) after surgery (p = 0.006, 0.013, and 0.000). Postoperative exodrift was statistically different between the first and second ULR muscle recessions at three to six months (2.89 +/-3.75 vs. 0.63 +/- 3.45 PD) and one year to final follow-up (11.52 +/- 5.50 vs. 2.32 +/- 3.53 PD) (p = 0.034 and 0.000). All of the first ULR muscle recession patients showed XT with deviation angles of more than 15 PD at the final follow-up. Regardless, the surgical success rate (<8 PD) after the second ULR recession was 63.16% (12 patients) among the total amount of patients with recurrent XT. CONCLUSIONS: This study shows that changes in exodrift after a second ULR muscle recession are less than changes after the first URL muscle recession among patients with recurrent XT. A second ULR muscle recession may be a useful surgery for small-angle XT patients with deviation angles of 25 PD or less after a first ULR muscle recession.

The Stabilization of Postoperative Exo-drift in Intermittent Exotropia after Surgical Treatment

PURPOSE: To investigate the long-term clinical course of intermittent exotropia after surgical treatment to determine whether and when postoperative exo-drift stabilizes, and the required postsurgery follow-up duration in cases of intermittent exotropia. METHODS: We retrospectively reviewed the medical records of patients diagnosed with intermittent exotropia who underwent surgical treatment between January 1992 and January 2006 at Yeungnam University Hospital and postoperatively performed regular follow-up examinations for up to 7 years. We also analyzed the difference in exo-drift stabilization, according to surgical procedure. RESULTS: A total of 101 patients were enrolled in the study. Thirty-one patients underwent lateral rectus recession and medial rectus resection (R&R) and 70 patients underwent bilateral lateral rectus recession (BLR). The postoperative angles of deviation increased significantly during the initial 36 months, but no subsequent significant changes were observed for up to 84 months. Follow-ups for 7 years revealed that more than 50% of the total amount of exo-drift was observed within the first postoperative year. In addition, the angles of deviation at 1 year correlated with those at 7 years postoperatively (Pearson correlation coefficient r = 0.517, p < 0.001). No significant exo-drift was observed after 36 months in patients who underwent BLR, whereas after 18 months in patients who underwent R&R. CONCLUSIONS: The minimum postoperative follow-up required after surgical treatment to ensure stable results is 36 months. In particular, careful follow-up is necessary during the first postoperative year to detect rapid exo-drift. Patients who underwent BLR required a longer follow-up than those who underwent R&R to ensure stable postoperative alignment.

Comparison of Astigmatism Induced by Combined Inferior Oblique Anterior Transposition Procedure and Lateral Rectus Recession Alone

PURPOSE: The purpose of this study is to compare the magnitude and axis of astigmatism induced by a combined inferior oblique (IO) anterior transposition procedure with lateral rectus (LR) recession versus LR recession alone. METHODS: Forty-six patients were retrospectively analyzed. The subjects were divided into two groups: those having concurrent inferior oblique muscle overaction (IOOA) and intermittent exotropia (group 1, 20 patients) and those having only intermittent exotropia as a control (group 2, 26 patients). Group 1 underwent combined anterior transposition of IO with LR recession and group 2 underwent LR recession alone. Induced astigmatism was defined as the difference between preoperative and postoperative astigmatism using double-angle vector analysis. Cylinder power, axis of induced astigmatism, and spherical equivalent were analyzed at 1 week, 1 month, and 3 months after surgery. RESULTS: Larger changes in the axis of induced astigmatism were observed in group 1, with 4.5° incyclotorsion, than in group 2 at 1 week after surgery (axis, 84.5° vs. 91°; p < 0.001). However, there was no statistically significant inter-group difference thereafter. Relaxation and rapid regression in the incyclotorsion of induced astigmatism were observed over-time. Spherical equivalent significantly decreased postoperatively at 1 month in both groups, indicating a myopic shift (p = 0.011 for group 1 and p = 0.019 for group 2) but did not show significant differences at 3 months after surgery (p = 0.107 for group 1 and p = 0.760 for group 2). CONCLUSIONS: Combined IO anterior transposition procedures caused an increased change in the axis of induced astigmatism, including temporary incyclotorsion, during the first week after surgery. However, this significant difference was not maintained thereafter. Thus, combined IO surgery with LR recession does not seem to produce a sustained astigmatic change, which can be a potential risk factor of postoperative amblyopia or diplopia compared with LR recession alone.

Comparison of Surgical Outcomes with Unilateral Recession and Resection According to Angle of Deviation in Basic Intermittent Exotropia

PURPOSE: The purpose of this study is to compare the surgical outcomes and near stereoacuities after unilateral medial rectus (MR) muscle resection and lateral rectus (LR) recession according to deviation angle in basic intermittent exotropia, X(T). METHODS: Ninety patients with basic type X(T) were included in this study. They underwent unilateral recession of the LR and resection of the MR and were followed postoperatively for at least 12 months. Patients were divided into three groups according to their preoperative deviation angle: group 1 or =40 PD. Surgical outcomes and near stereoacuities one year after surgery were evaluated. Surgical success was defined as having a deviation angle range within +/-10 PD for both near and distance fixation. RESULTS: Among 90 patients, groups 1, 2, and 3 included 30 patients each. The mean age in groups 1, 2, and 3 was 9.4 years, 9.4 years, and 11.0 years, respectively. The surgical success rates one year after surgery for groups 1, 2, and 3 were 80.0%, 73.3%, and 73.3% (chi-square test, p = 0.769), respectively. The undercorrection rates for groups 1, 2, and 3 were 16.7%, 23.3%, and 26.7%, and the overcorrection rates were 3.3%, 3.3%, and 0%, respectively. The mean preoperative near stereoacuities for groups 1, 2, and 3 were 224.3 arcsec, 302.0 arcsec, and 1,107.3 arcsec, and the mean postoperative near stereoacuities were 218.3 arcsec, 214.7 arcsec, and 743.0 arcsec (paired t-test; p = 0.858, p = 0.379, p = 0.083), respectively. CONCLUSIONS: In basic X(T) patients, the amount of angle deviation has no influence on surgical outcomes in unilateral LR recession and MR resection. The near stereoacuities by one year after LR recession and MR resection for intermittent X(T) were not different among patient groups separated by preoperative deviation angle.

Effect of Watching 3-Dimensional Television on Refractive Error in Children

PURPOSE: To investigate the effect of watching 3-dimensional (3D) television (TV) on refractive error in children. METHODS: Sixty healthy volunteers, aged 6 to 12 years, without any ocular abnormalities other than refractive error were recruited for this study. They watched 3D TV for 50 minutes at a viewing distance of 2.8 meters. The image disparity of the 3D contents was from -1 to 1 degree. Refractive errors were measured both before and immediately after watching TV and were rechecked after a 10-minute rest period. The refractive errors before and after watching TV were compared. The amount of refractive change was also compared between myopes and controls. The refractive error of the participants who showed a myopic shift immediately after watching TV were compared across each time point to assure that the myopic shift persisted after a 10-minute rest. RESULTS: The mean age of the participants was 9.23 ± 1.75 years. The baseline manifest refractive error was -1.70 ± 1.79 (-5.50 to +1.25) diopters. The refractive errors immediately after watching and after a 10-minute rest were -1.75 ± 1.85 and -1.69 ± 1.80 diopters, respectively, which were not different from the baseline values. Myopic participants (34 participants), whose spherical equivalent was worse than -0.75 diopters, also did not show any significant refractive change after watching 3D TV. A myopic shift was observed in 31 participants with a mean score of 0.29 ± 0.23 diopters, which resolved after a 10-minute rest. CONCLUSIONS: Watching properly made 3D content on a 3D TV for 50 minutes with a 10-minute intermission at more than 2.8 meters of viewing distance did not affect the refractive error of children.

Laser-assisted In Situ Keratomileusis for Correction of Astigmatism and Increasing Contact Lens Tolerance after Penetrating Keratoplasty

PURPOSE: To determine effectiveness of laser-assisted in situ keratomileusis (LASIK) in the treatment of astigmatism following penetrating keratoplasty (PK). METHODS: We performed a retrospective review of medical records of patients who underwent LASIK following PK and had over 1 year of follow-up data. RESULTS: Twenty-six patients (26 pairs of eyes) underwent LASIK following PK. Mean age of the patients at the time of LASIK was 40.7 years (range, 26 to 72 years). Following LASIK, the mean cylinder was reduced by 2.4 diopters and mean reduction of cylinder after LASIK was 65.4% from the preoperative values at the last follow-up visit. Uncorrected visual acuity became 20 / 50 or better in 69.2% of the eyes after LASIK. Best-corrected visual acuity became 20 / 50 or better in 73.1% of the eyes after LASIK. All of them were intolerable to contact lenses before LASIK. After LASIK, 6 pairs (23.1%) did not need to use contact lenses and 18 pairs (69.2%) were tolerable to using contact lenses or spectacles. There were no significant endothelial cell density changes 12 months after LASIK (p = 0.239). CONCLUSIONS: LASIK is effective in the treatment of astigmatism following PK and increases contact lens and spectacle tolerance.

Accommodative Esotropia Who Needs Spectacles for Good Ocular Alignment after Refractive Shift below +2.00 Diopters

PURPOSE: The aim of this study is to investigate the clinical characteristics of patients diagnosed with refractive accommodative esotropia (RAE) whose refractive errors were gradually reduced to below +2.00 diopters (D) during follow-up but use of spectacles was still required for maintenance of good ocular alignment. METHODS: We conducted a retrospective review of the medical records of patients diagnosed with RAE from 1995 to 2011. Patients were divided into 2 groups according to their ocular alignment at the last visit. Inclusion criteria were hyperopia > or =+2.00 D detected with cycloplegic refraction at the initial visit, which then became mild hyperopia ( or =10 prism diopters [PD]) without spectacles (group A) and 66 patients showed good ocular alignment (<10 PD) without spectacles (group B) at the last visit. No statistically significant differences in the spherical equivalent of the refractive errors at the initial and last visit were observed between the two groups. A significantly lower number of positive responses on the Lang I stereotest was observed in group A (n = 1, 3.8%) compared to group B (n = 22, 33.3%) (p = 0.003). There were increasing trends toward group A with worsening stereoacuity measured by the Stereo Fly Stereotest between the two groups (p = 0.016, linear by linear association). The results of the Lang I test, Stereo Fly Stereotest, and duration between the onset of esotropia and prescribing spectacles showed a significant association with the discontinuation of spectacles in the univariate logistic analysis. CONCLUSIONS: Stereoacuity showed more significant associations than refractive errors in RAE with refractive error <+2.00 D but still required spectacles for maintenance of good ocular alignment. The prompt treatment of accommodative esotropia at the onset of esotropia is important for the discontinuation of spectacles.

Clinical Usefulness of Binocular Multifocal Electroretinography in Patients with Monocular Macular Disease

PURPOSE: To evaluate the clinical usefulness of binocular multifocal electroretinography (mfERG) by comparing results with conventional monocular mfERG in patients with monocular macular disease. METHODS: mfERG testing was conducted on 32 patients with monocular macular disease and 30 normal subjects. An initial mfERG was simultaneously recorded from both eyes with two recording electrodes under binocular stimulation. A second mfERG was subsequently recorded with conventional monocular stimulation. Amplitudes and implicit times of each ring response of the binocular and monocular recordings were compared. Ring ratios of the binocular and monocular recording were also compared. RESULTS: In the macular disease group, there were no statistical differences in amplitude or implicit time for each of the five concentric rings between the monocular and binocular recordings. However, with binocular simulation, the ring ratios (ring 1 / ring 4, ring 1 / ring 5) were significantly reduced in the affected eye. In the normal control group, there were no statistical differences in any parameters between the monocular and binocular recordings. CONCLUSIONS: Binocular mfERG could be a good alternative to the conventional monocular test. In addition, given that the test needs stable fixation of the affected eye during the binocular test, the reliability of the test results could be improved, especially for patients with monocular macular disease.

Astigmatic Changes after Horizontal Rectus Muscle Surgery in Intermittent Exotropia

PURPOSE: To evaluate the changes of refractive astigmatism after horizontal rectus muscle surgery in intermittent exotropic children. METHODS: Sixty-nine exotropic patients were retrospectively reviewed. Of those, 35 patients received unilateral lateral rectus recession (BLR group, 35 eyes) and 34 patients received unilateral lateral rectus recession and medial rectus resection (R&R group, 34 eyes). Non-cycloplegic refractions were measured until 6 months postoperatively. Spherical equivalent (SE), J0 and J45 using power vectors were calculated to determine and compare the changes of refractive astigmatism and axis in both groups. RESULTS: SE significantly decreased after surgery for the first week and did not changed thereafter in both groups (p = 0.000 and p = 0.018, respectively). In BLR group, J0 showed significant changes at the first week and 1 month after surgery (p = 0.005 and p = 0.016, respectively), but in R&R group, J0 changed significantly between 1 week and 3 months postoperatively (p = 0.023 and p = 0.016, respectively). J45 did not change significantly as time passed in both groups (all p > 0.05). There was no statistically significant difference in the magnitude of changes in SE, J0 and J45 between the two groups after the 6-month follow-up (p = 0.500, p = 0.244 and p = 0.202, respectively). CONCLUSIONS: Horizontal rectus muscle surgery in intermittent exotropic children tends to induce a statistically significant change in astigmatism in the with-the-rule direction and myopic shift in SE. This astigmatism change seems to occur within the first 3 months after surgery. Thus, astigmatism induced by surgery should be checked and corrected at least 3 months after horizontal strabismus surgery.

O impacto da visão monocular congênita versus adquirida na qualidade de visão autorrelatada / Impact of congenital versus acquired monocular vision as self-reported vision

Objetivos: Quando a visão de um olho está preservada (visão monocular) e há alto risco, baixo prognóstico e/ou recursos limitados para a cirurgia do olho contralateral, não é claro se o beneficio da binocularidade supera o da reorientação para visão monocular. O objetivo é quantificar o impacto da qualidade de visão referida entre a condição binocular e monocular e, nesse último caso, entre congênita e adquirida. Métodos: Pacientes com acuidade visual (AV) com AV>0,5 em cada olho foram submetidos ao questionário estruturado de 14 perguntas (VF-14), onde a pontuação de 0 a 100 indica o nível de satisfação do paciente com sua visão, variando de baixo a alto respectivamente. Dados epidemiológicos e pontuações dos quatro grupos foram registrados e submetidos à análise estatística. Resultados: A entrevista pelo VF-14 com 56 indivíduos revelou que a pontuação mais alta foi similar entre os controles e os portadores de visão monocular congênita, e níveis intermediários e baixos foram obtidos por indivíduos com visão monocular adquirida e cegos bilaterais, respectivamente (p<0,001). As atividades mais difíceis para os indivíduos com visão monocular adquirida foram identificar letras pequenas, reconhecer pessoas, distinguir sinais de trânsito e assistir TV. Conclusão: O estudo confirmou que a perda da visão tem impacto desfavorável no desempenho referido das atividades sendo maior na visão monocular adquirida do que na congênita. Os dados sugerem que medidas de reabilitação devem ser consideradas para melhorar a qualidade da visão em doenças intratáveis ou de alto risco ou de baixo prognóstico.

Purpose: When the vision in one eye is preserved (monocular vision) and there is high risk, low prognosis and/or limited resources to the fellow eye surgery, it is unclear if the benefit of binocularity outweighs the reorientation for monocular vision. The goal is to quantify the impact of the quality of vision of both binocular and monocular condition, and in this latter case, between congenital and acquired. Methods: Patients with visual acuity (VA)>0.5 in each eye underwent a structured questionnaire of 14 questions (VF-14), which the score 0-100 indicates the level of patient satisfaction with their vision, ranging from low to high respectively. Epidemiological data and scores of the four groups were recorded and analyzed statistically. Results: The interview by the VF-14 with 56 subjects revealed that the highest score was similar between controls and patients with congenital monocular vision, and low and intermediate levels were obtained by individuals with acquired monocular vision and bilaterally blind, respectively (p<0.001). The more difficult activities for individuals with acquired monocular vision were to identify small print, recognize people, to distinguish traffic lights and watch TV. Conclusion: The study confirmed that the vision loss has an adverse impact on the performance of such activities being higher in congenital than in acquired monocular vision. The data suggest that rehabilitation measures should be considered to improve the quality of vision in intractable diseases, high risk or low prognosis.

Cirurgia de catarata: características e opiniões de pacientes com visão mono versus binocular / Cataract surgery: characteristics and opinions of patients with monocular versus binocular vision

OBJETIVO: Verificar em dois grupos de pacientes com visão monocular (grupo 1) e com visão binocular (grupo 2), a serem submetidos à cirurgia de catarata num hospital universitário, opiniões em relação ao problema ocular, à qualidade da visão e à cirurgia de catarata. MÉTODOS: Foi realizado estudo transversal e comparativo, de forma consecutiva, por meio de questionário estruturado, aplicado por entrevista a pacientes, elaborado a partir de estudo exploratório e medidas acuidade visual e causa da perda visual. RESULTADOS: A amostra foi constituída por 96 indivíduos do grupo 1 (50,0 por cento homens; 50,0 por cento mulheres, com idade entre 41 e 91 anos, média 69,3 anos ± 10,4 anos) e 110, do grupo 2 (40,9 por cento homens; 59,1 por cento mulheres, com idade entre 40 e 89 anos, média 68,2 anos ± 10,2 anos). A maioria dos indivíduos de ambos os grupos apresentava baixa escolaridade. Não houve diferença estatisticamente significante entre os grupos em relação ao sexo (p=0,191), à idade (p=0,702) e à escolaridade (p=0,245). Não exerciam atividade laboral 95,8 por cento dos indivíduos do grupo 1 e 83,6 por cento, do grupo 2 (p=0,005) e 30,4 por cento do grupo 1 mencionaram não ter possibilidade de trabalhar por causa da deficiência visual. Observou-se acuidade visual do olho a ser operado menor que 0,05 em 40,6 por cento (grupo 1) e 33,6 por cento (grupo 2), entre 0,25 e 0,05. Quase a totalidade dos indivíduos de ambos os grupos afirmou ter dificuldade para realização das atividades de vida diária e qualificou como insuficiente a respectiva acuidade visual; 71,9 por cento dos entrevistados do grupo 1 e 71,6 por cento, do grupo 2 mencionaram saber a causa da visão fraca; desses, 87,1 por cento do grupo 1 e 83,3 por cento do grupo 2 referiram a catarata como causa da baixa acuidade visual. CONCLUSÃO: Os indivíduos de ambos os grupos tiveram acesso à cirurgia de catarata com acuidade visual menor do que a idealmente indicada; os pacientes com visão monocular apresentaram acuidade visual significativamente menor em relação aos com visão binocular; a maioria dos entrevistados de ambos os grupos referiu dificuldades para realizar atividades cotidianas como consequência da baixa visão; muitos indivíduos de ambos os grupos desconheciam a causa da dificuldade visual ou a atribuíram a outra causa que não a catarata.

PURPOSE: To verify in two groups of patients: monocular (group 1) and binocular vision (group 2) to be submitted to cataract surgery at an University Hospital, opinions, expectances and emotional reactions related to the ocular problem, to the quality of vision and to cataract surgery. METHODS: A transversal comparative and consecutive study was performed using a structured questionnaire applied by patients interview. The questionnaire was elaborated from a previous exploratory study; visual acuity and cause of the visual loss were evaluated. RESULTS: The sample was constituted by 96 persons of group 1 (50.0 percent male; 50.0 percent female, ages ranging from 41 to 91 years; average 69.3 years ± 10.4 years) and 110 persons of group 2 (40.9 percent male; 59.1 percent female, ages ranging from 40 to 89 years; average 68.2 years ± 10.2 years). The majority of persons of both groups presented low educational level. There was no statistically significant difference between the groups in relation to gender (p=0.191), age (p=0.702) and educational level (p=0.245). No work activity was mentioned in 95.8 percent of the persons of group 1 and 83.6 percent of group 2 (p=0.005) and 30.4 percent of group 1 informed the impossibility to work due the visual impairment. Visual acuity of the eye to be operated was less than 0.05 in 40.6 percent (group 1) and in 33,6 percent (group 2), presented visual acuity ranging from 0.05 to 0.25. Almost the totality of the persons of both groups informed difficulties to perform activities of daily life and qualified as insufficient their visual acuities; 71.9 percent of the patients of group 1 and 71.6 percent of group 2 informed to know the reason of low vision; among these, 87.1 percent of group 1 and 83.3 percent of group 2 mentioned cataract as the reason of low visual acuity. CONCLUSION: It was concluded that the patients of both groups were submitted to cataract surgery with visual acuities less than the visual ...

Desempenho visual após implante de uma lente intraocular asférica multifocal difrativa / Visual performance after implantation of an aspheric multifocal diffractive intraocular lens

OBJETIVO: Avaliar a acuidade visual a distancia, intermediária e perto após o implante de uma lente intraocular (LIO) asférica multifocal difrativa AcrySof® ReSTOR® SN6AD1. MÉTODOS: Estudo prospectivo de 50 pacientes com catarata submetidos à facoemulsificação e implante de LIO AcrySof® ReSTOR®. Foram avaliados acuidade visual sem correção (AVSC), acuidade visual com correção (AVCC) para longe, acuidade visual para perto corrigida para longe (AVPC) e acuidade visual intermediária corrigida para longe (AVIC). Um questionário de satisfação e fenômenos visuais foi administrado ao final do estudo. RESULTADO: Após três meses de cirurgia, a média das acuidades (logMAR) era: AVSC, 0,05 ± 0,07; AVCC, 0,00 ± 0,01; AVPC, 0,00 ± 0,0, e AVIC, 0,15 ± 0,05. A AVCC e AVPC era de 20/25 ou melhor em todos os pacientes, sendo a AVIC J3 ou melhor em 83 por cento dos pacientes. Pacientes relataram excelente desempenho visual nas questões relacionadas a atividades para distância, intermediário, e perto com pouca ou nenhuma dificuldade. Nenhum paciente relatou halos ou 'glare' severos, sendo os mesmos caracterizados entre nenhum a moderado. CONCLUSÃO: A LIO asférica AcrySof® ReSTOR® SN6AD1 mostrou excelentes resultados na visão para longe, perto e intermediário, além de apresentar uma baixa incidência de fenômenos visuais.

PURPOSE: To evaluate distance, intermediate, and near vision after aspheric multifocal diffractive AcrySof® ReSTOR® SN6AD1 intraocular lens (IOL) implantation. METHODS: Prospective study of 50 patients with cataract that had phacoemulsification and AcrySof® ReSTOR® IOL implantation. Uncorrected distance vision acuity (UDVA), corrected distance visual acuity (CDVA), distance-corrected near visual acuity (DCNVA), and distance-corrected intermediate visual acuity (DCIVA) were measured postoperatively. A patient-satisfaction and visual phenomena questionnaire was administered at the end of the study. RESULTS: Three months postoperatively, the mean acuities (logMAR) were: UCDV, 0,05 ± 0,07; CDVA, 0,00 ± 0,01; DCNVA, 0,00 ± 0,0, and AVIC, 0,15 ± 0,05. The CDVA and DCNVA were 20/25 or better in all patients, with DCIVA of J3 or better in 83 percent of the patients. Patients reported good performance for distance, intermediate, and near visual tasks with no or minimal difficulty with specific tasks. No patient reported severe visual phenomena; halos and glare were rated as none to moderate. CONCLUSION: The aspheric IOL AcrySof® ReSTOR® SN6AD1 provide good functional vision at far, intermediate, and near distance, and a low incidence of visual disturbances.

Horizontal lang two-pencil test as a screening test for stereopsis and binocularity.

Purpose: To assess the horizontal Lang two-pencil test as a bedside test to detect gross stereopsis. Materials and Methods: Eighty-four strabismic subjects divided into two groups based on the amount of deviation, and 40 normal subjects were studied. Sensory status examination including binocularity and stereopsis were evaluated with Bagolini, Titmus test and the Netherlands organisation for applied scientific research (TNO), Randot, synoptophore and horizontal Lang two-pencil test. Results: The subjects in the group with smaller deviation showed better performance on all the four stereo tests and over 90% demonstrated presence of fusion. When compared to TNO and Randot for determining presence of stereopsis, the horizontal Lang two-pencil test demonstrated sensitivity of 100% and 83.9%, specificity of 77.8% and 73.7%, and negative predictive value of 100% and 100% respectively. It also showed 100% specificity as a test for binocularity when compared with the Bagolini striated glass test. Conclusion: Horizontal Lang two-pencil test, an easily performed test with a high sensitivity and negative predictive value can be used as a screening test to detect gross stereopsis and binocularity.

Estrabismos: da teoria à prática, dos conceitos às suas operacionalizações / Strabismus: from theory to practice, from concepts to its operational attainment

Analisam-se particularidades inerentes ao estudo dos estrabismos, tais como as dificuldades para suas definições e os diferentes modos com os quais eles podem ser concebidos, a relatividade com que as posições binoculares possam ser interpretadas e os elementos referenciais necessários para a circunscrição dessas questões. A partir daí, discute-se o conceito de posição primária do olhar e as condições de sua operacionalização, concluindo-se pela impossibilidade de concretização desse ponto "zero", a partir do qual seriam feitas as medidas dos estrabismos e as quantificações de movimentos oculares. A seguir, passa-se ao exame da construção dos múltiplos sistemas referenciais aplicáveis à quantificação dos estrabismos, de cuja falta de consenso sobre qual deles usar decorrem implicações práticas elementares, como a falta de padronização do modo de superposição ortogonal de prismas, para a medida de desvios combinados, horizontal e vertical. Comenta-se a assimetria funcional das rotações oculares e suas exceções. Também se analisa a precisão com que se pode fazer a medida de um estrabismo, levando à conclusão sobre a impropriedade de uso de medidas fracionárias com as unidades angulares mais comumente usadas. Finalmente, são comentados alguns problemas técnicos dessas avaliações, tais como o das dificuldades operacionais relacionadas à dioptria-prismática, os subordinados ao uso de prismas e os da ocorrência de efeitos prismáticos pelo uso de lentes convencionais.

Some particular points concerning the study of strabismus are analyzed, specially, the difficulties for definitions and the different ways it can be conceived, besides the relativity of binocular positions interpretation, and the necessary referential elements for circumscribing such questions. Then, the concept of primary position of gaze is discussed as well as the conditions for its operational attainment, leading to the conclusion that it is materially impossible to achieve this "zero" point, from which all other measurements of strabismus or ocular movements should be done. In sequence, the construction of multiple referential systems applying the quantification of strabismus are examined. The lack of consensual agreement about which should be used as the standard system causes elementary practical implications, as the lack of agreement about how to superimpose orthogonal prisms for the measurement of associated horizontal and vertical deviations. The functional asymmetry of ocular rotations and its exceptions are commented. The accuracy that the measurements of strabismus can be performed is analyzed, leading to the conclusion that fractional figures using the commonest angular unities are improper. At last, some technical problems related to such evaluations are also commented, as operational difficulties related to prism-diopter unity, concerning the use of prisms, and prismatic effects due to the use of conventional optical glasses.

Gains beyond cosmesis: Recovery of fusion and stereopsis in adults with longstanding strabismus following successful surgical realignment.

We evaluated recovery of binocularity in 15 chronically strabismic, non-fusing (with neutralizing prisms) adults following successful surgical alignment. We included > or =12-year-olds, with best corrected visual acuity (BCVA) > or =20/60, and excluded those with: anisoacuity> 2 lines-Snellen; failed realignment judged by> 10 prism diopters (PD) horizontal and> 4 PD vertical. Six-week outcomes were: fusion by Worth Four-Dots (WFDT) and Bagolini striated glasses (BSG) and stereopsis by Titmus test and the Netherlands organisation for applied scientific research (TNO) test. Baseline data in medians (range): age 18 (12-40) years, strabismus 45 (19-95) PD, duration 14 (0.5-24) years, 12 females; 12 exotropes, three esotropes; visual acuity was 20/20 in 10, while none had BCVA < 20/60. Postoperative strabismus measured 6 PD (range:0-10). By six weeks none suppressed: WFDT findings showed eight fused at distance and 13 at near; and on BSG figures were 10 and 13 respectively. Stereopsis was demonstrated by 13 on Titmus and by 10 on TNO tests. It is concluded that longstanding strabismic adults with good vision can recover fusion and stereopsis following successful squint surgery.

Evaluation of single-stage adjustable strabismus surgery under conscious sedation.

PURPOSE: To evaluate the feasibility and stability of ocular alignment after single-stage adjustable strabismus surgery (SSASS) performed under topical anesthesia. MATERIALS AND METHODS: Forty-five patients of concomitant exodeviations were randomized into three groups of 15 cases each and were operated with three different techniques: Group I - conventional surgery, Group II - two-stage adjustable suture technique with suture adjustment performed 6h postoperatively and Group III- SSASS under topical anesthesia and intravenous conscious sedation with midazolam and fentanyl. Intraoperative suture adjustment was done by giving a cross target to the patient on the ceiling at the end of the procedure. Surgical results were compared among the three groups at three months follow-up. Intraoperative hemodynamic parameters and patients' experience of the surgery (by questionnaire) were also compared. RESULTS: Mean preoperative deviation for distance in Groups I, II, III was -41.67 prism diopter (pd) +/-9.0, -38.93 pd +/-11.05 and -41.87 pd +/-8.91 ( P =0.6) respectively. At three months, mean correction achieved for distance was +31.87 pd +/-11.71, +35.47 pd +/-10.86 and +42.80 pd +/-10.71 respectively which was significantly different between Group III and Group I ( P =0.03). Intraoperatively all hemodynamic parameters remained stable and comparable ( P =0. 5) in all groups. Intraoperative pain ( P < 0.001) and time taken for surgery ( P < 0.001) was more in the SSASS group. Amount of exodrift was 10-12 pd, comparable in all three groups ( P = 0.5). CONCLUSIONS: SSASS, performed under topical anesthesia, is safe and has better outcomes than conventional recession-resection surgery for concomitant exodeviation. An overcorrection of about 10-12 pd is recommended to check the exodrift and achieve stable alignment.

Visual control in children with developmental dyslexia / Controle visual em crianças com dislexia do desenvolvimento

PURPOSE: To assess binocular control in children with dyslexia. METHODS: Cross-sectional study with 26 children who were submitted to a set of ophthalmologic and visual tests. RESULTS: In the dyslexic children less eye movement control in voluntary convergence and unstable binocular fixation was observed. CONCLUSION: The results support the hypothesis that developmental dyslexia might present deficits which involve the magnocellular pathway and a part of the posterior cortical attentional network.

OBJETIVO: Avaliar o controle binocular em crianças com dislexia. MÉTODOS: Estudo transversal do qual participaram 26 crianças, nas quais foram aplicadas uma série de exames oftalmológicos e visuais. RESULTADOS: Nas crianças com dislexia observou-se controle menor na convergência voluntária e na estabilidade da fixação binocular. CONCLUSÃO: Os resultados apóiam a hipótese de que na dislexia do desenvolvimento podem ocorrer déficits que envolvem a via visual magnocelular e uma parte da rede cortical posterior da atenção.

Fetal ocular distance in normal pregnancies.

OBJECTIVE: To construct reference ranges of fetal ocular distance (interocular and binocular distance) and to evaluate the relationships between the gestational ages and fetal ocular distance. MATERIAL AND METHOD: Six hundred and two normal pregnant women were evaluated from the 15th to 40th week of gestation. Fetal ocular distance (interocular and binocular distances) was added to routine biometric measurements for normal fetuses. The fetal ocular distance (interocular and binocular distances) was also related to gestational age. RESULTS: Five hundred and ninety five measurements were used for analyses. A linear regression and correlation were observed between gestational age (GA) and interocular distance (y = 2.304 + 0.510 x GA, R2 = 0.887; p < 0.0001), and binocular distance (y = 2.590 + 1.420 x GA, R2 = 0.953; p < 0.0001). A linear growth function was observed between biparietal diameter (BPD) and both interocular distance (y = 2.854 + 0.203 x BPD, R2 = 0.888; p < 0.0001), and binocular distance (y = 3.893 + 0.568 x BPD, R2 = 0.965; p < 0.0001). CONCLUSION: The present study provides normative data of fetal interocular distance and binocular distance. These data may be helpful in detection of fetal hypotelorism or hypertelorism.

Preferred clinical practice in convergence insufficiency in India: a survey.

PURPOSE: Convergence insufficiency (CI) is a common binocular vision disorder. However, there is a lack of consensus regarding the treatment most appropriate for CI. The aim of the study was to investigate the treatment for CI by surveying the ophthalmologists regarding the most common treatment modalities used in India. MATERIALS AND METHODS: Four hundred questionnaires were distributed amongst ophthalmologists attending different sessions of the Delhi Ophthalmological Society annual conference held in April 2007. Two hundred and three ophthalmologists responded (response rate 50.75%). The responders included 109 private practitioners, 57 consultants attached to teaching institutes and 37 residents. RESULTS: The majority of ophthalmologists (66.7%) claimed encountering > 5% outpatient department patients with CI. Pencil push-ups therapy (PPT) was the most common first line of treatment offered by ophthalmologists (79%) followed by synoptophore exercises (18%). Only 3% referred the patients to optometrists. Thirty per cent ophthalmologists claimed good results with PPT, which was significantly higher in private practitioners (35%). Only 26% ophthalmologists explained physiological diplopia to patients on a regular basis and reported significantly higher percentage of patients (46.3%) with good results. Only 12.3% ophthalmologists needed to refer > 30% patients for synoptophore exercises. For failure of PPT 86.7% considered lack of compliance as the major reason as perceived by ophthalmologists. CONCLUSIONS: This survey suggested that most ophthalmic practitioners prescribed PPT as the initial treatment for CI and had satisfactory results with PPT. The majority of the practitioners did not explain to the patient about physiological diplopia. Explaining physiological diplopia may improve outcome, as perceived from the survey.