Evaluation of three superior oblique surgical weakening procedures for A-pattern strabismus / Avaliação de três tipos de cirurgia de enfraquecimento dos músculos superiores oblíquos no estrabismo com padrão em A

ABSTRACT Purpose: To evaluate three superior oblique surgical weakening procedures for correcting A-pattern strabismus: tenectomy, superior oblique hang-back recession, and that involving the use of superior oblique suture spacers. Methods: The inclusion criteria were A-pattern strabismus ≥10Δ and horizontal deviation ≥10Δ, with no other ocular abnormality and a follow-up period of ≥6 months. The 24 patients (mean age, 16.3 ± 8.1 years; mean postoperative follow-up, 9.63 ± 3.11 months) were randomly divided into three groups of 8 patients each. Sigmascan® Pro 5.0 software was used to measure the degree of torsion pre- and postoperatively. Results: Preoperatively, the mean angles of A-pattern deviation were 19.33Δ° ± 3.53Δ° (tenectomy group), 15.71Δ° ± 1.11Δ° (hang-back recession group), and 14.62Δ° ± 1.18Δ° (suture spacers group); these values did not differ significantly. At the final follow-up examination, the mean angles of A-pattern deviation were 4.67Δ° ± 0.67Δ° (tenectomy group), 6.29Δ° ± 1.48Δ° (hang-back recession group), and 4.38Δ° ± 1.03Δ° (suture spacers group), with no statistically significant difference in the correction in A-pattern strabismus among the three groups. Preoperatively, the mean torsional angles were +5.4° ± 3.9° (tenectomy group), +5.6° ± 4.9° (hang-back recession group), and +6.0° ± 3.3° (suture spacers group); these values did not differ significantly. At the final follow-up examination, the mean torsional angles were + 0.3° ± 5.6° (tenectomy group), +0.5° ± 4.6° (hang-back recession group), and +0.2° ± 5.2° (suture spacers group), with no statistically significant difference in the intorsion correction among the three groups. Conclusion: All three superior oblique weakening procedures were effective for correcting A-pattern strabismus and fundus intorsion.

RESUMO Objetivo: Avaliar três procedimentos de debilitamento dos músculos oblíquos superiores para a correção de estrabismo com padrão em A: tenectomia, sutura em rédea (hang-back recession) e o uso de espaçadores de sutura oblíqua superior. Métodos: Os critérios de inclusão foram estrabismo padrão em A ≥10Δ e desvio horizontal ≥10Δ, sem outras anormalidades oculares e tempo de acompanhamento ≥6 meses. Os 24 pacientes (média de idade de 16,3 ± 8,1 anos; média de seguimento pós-operatório de 9,63 ± 3,11 meses) foram divididos aleatoriamente em três grupos de 8 pacientes cada. O programa Sigmascan® Pro 5.0 foi utilizado para medir o grau de torção no pré e pós-operatório. Resultados: No pré-operatório, a média e o desvio padrão dos ângulos de padrão em A foram de 19,33Δ° ± 3,53Δ° (grupo da tenectomia), 15,71Δ° ± 1,11Δ° (grupo da sutura em rédea), 14,62Δ° ± 1,18Δ° (grupo de espaçadores de sutura); esses valores não diferiram significativamente. No exame pós-operatório, a média e o desvio padrão dos ângulos de desvio do padrão em A foram de 4,67Δ° ± 0,67Δ° (grupo da tenectomia), 6,29Δ° ± 1,48Δ° (grupo da sutura em rédea), 4,38Δ° ± 1,03Δ° (grupo de espaçadores de sutura), sem diferença estatisticamente significativa na correção do estrabismo padrão em A entre os três grupos. No pré-operatório, os ângulos médios de torção foram de +5,4o ± 3,9° (grupo de tenectomia), +5,6° ± 4,9° (grupo da su­tura em rédea), e +6,0° ± 3,3° (grupo de espaçadores de sutura), esses valores não diferiram significativamente. No pós-operatório, os ângulos médios de torção foram de +0,3° ± 5,6° (grupo da tenectomia), +0,5° ± 4,6° (grupo da sutura em rédea), e +0,2° ± 5,2° (grupo de espaçadores de sutura), sem diferença estatisticamente significativa na correção da intorção entre os três grupos. Conclusão: Os três procedimentos de debili­tamento dos músculos oblíquos superiores foram efetivos para a correção do estrabismo com padrão em A e da intorção ocular observada na fundoscopia.

Dysfunction in the fellow eyes of strabismic and anisometropic amblyopic children assessed by visually evoked potentials / Alterações dos potenciais visuais evocados nos olhos contralaterais de crianças com ambliopia estrabísmica e anisometrópica

ABSTRACT Purpose: To evaluate visual acuity and transient pattern reversal (PR) visual evoked potentials (VEPs) in the fellow eyes of children with strabismic and/or anisometropic amblyopia. Methods: Children diagnosed with strabismic and/or anisometropic amblyopia were recruited for electrophysiological assessment by VEPs. Monocular grating and optotype acuity were measured using sweep-VEPs and an Early Treatment Diabetic Retinopathy Study chart, respectively. During the same visit, transient PR-VEPs of each eye were recorded using stimuli subtending with a visual angle of 60', 15', and 7.5'. Parameters of amplitude (in μV) and latency (in ms) were determined from VEP recordings. Results: A group of 40 strabismic and/or anisometropic amblyopic children (22 females: 55%, mean age= 8.7 ± 2.2 years, median= 8 years) was examined. A control group of 19 healthy children (13 females: 68.4%, mean age= 8.2 ± 2.6 years, median= 8 years) was also included. The fellow eyes of all amblyopes had significantly worse optotype acuity (p=0.021) than the control group, regardless of whether they were strabismic (p=0.040) or anisometropic (p=0.048). Overall, grating acuity was significantly worse in the fellow eyes of amblyopes (p=0.016) than in healthy controls. Statistically prolonged latency for visual angles of 15' and 7.5' (p=0.018 and 0.002, respectively) was found in the strabismic group when compared with the control group. For the smaller visual stimulus (7.5'), statistically prolonged latency was found among all fellow eyes of amblyopic children (p<0.001). Conclusions: The fellow eyes of amblyopic children showed worse optotype and grating acuity, with subtle abnormalities in the PR-VEP detected as prolonged latencies for smaller size stimuli when compared with eyes of healthy children. These findings show the deleterious effects of amblyopia in several distinct visual functions, mainly those related to spatial vision.

RESUMO Objetivo: Avaliar a acuidade visual e os potenciais visuais evocados transientes por reversão de padrões no olho contralateral de crianças com ambliopia estrabísmica e/ou anisometrópica. Métodos: Foram avaliados os potenciais visuais evocados de crianças com ambliopia estrabísmica e/ou anisometrópica. As acuidades visuais monoculares de grades e de optotipos foram mensuradas utilizando o PVE de varredura e a tabela EDTRS, respectivamente. Na mesma visita, foram registrados os PVERP transients de cada olho usando estímulos de ângulo visual de 60'; 15' e 7,5'. Parâmetros de amplitude (em microvolts) e latência (em milissegundos) foram determinados para os registros dos potenciais visuais evocados. Resultados: Um grupo de 40 crianças amblíopes estrábicas e/ou anisometrópicas (22 meninas - 55%, media idade= 8,7 ± 2,2, mediana= 8) foi examinado. Um grupo de 19 crianças saudáveis (13 meninas 68,4%, media idade= 8,2 ± 2,6, mediana= 8) de controle também foi incluído. A acuidade visual por optotipos foi significativamente pior (p=0,021) nos olhos contralaterais de todos os amblíopes, quando comparado com o grupo controle, independentemente se estrábico (p=0,040) ou anisometrópico (p=0,048). No geral, a acuidade visual por grades foi significativamente pior nos olhos contralaterais dos amblíopes (p=0,016), quando comparados com o grupo controle. Foi encontrada latência estatisticamente prolongada para ângulos visuais de 15' (p=0,018) e 7,5' (p=0,002) no grupo estrábico, quando comparado com o grupo controle. Para o menor estímulo visual (7,5') foi encontrada latência estatisticamente prolongada nos olhos contralaterais de todas crianças amblíopes (p<0,001). Conclusões: Os olhos contralaterais de crianças amblíopes mostraram pior acuidade visual de optotipo e de resolução de grades, com alterações sutis nos PVERP, detectadas pelas latências prolongadas para estímulos de menor tamanho, quando comparados com os olhos de crianças saudáveis. Estes resultados mostram os efeitos deletérios da ambliopia em várias funções visuais distintas, principalmente relacionadas à visão espacial.

Antielevation Syndrome after Bilateral Anterior Transposition of the Inferior Oblique Muscles

No abstract available.

Difference of Self-identity Levels between Strabismus Patients and Normal Controls

PURPOSE: To evaluate differences in self-identity in patients diagnosed with strabismus, patients who underwent strabismus surgery, and healthy control individuals. METHODS: Self-identity testing was done during a military service physical examination. There were three subject groups: subjects with strabismus (group 1), subjects who had undergone corrective strabismus surgery (group 2), and subjects free of strabismus (group 3). The self-identity test was comprised of six sub-sections (subjectivity, self-acceptance, future confidence, goal orientation, initiative, and familiarity). Statistical significance of the sub-sections was compared across the three groups. Correlations in age at the time of surgery and across the six sub-sections were investigated in group 2. RESULTS: A total of 351 subjects were enrolled in the study; 96 subjects were in group 1, 108 subjects were in group 2, and 147 subjects were in group 3. Significant differences were evident in subjectivity, self-acceptance, initiative and familiarity between groups 1 and 3. No significant differences were found between groups 2 and 3. In group 2, statistical significance was evident between age at surgery and initiative and familiarity (r = −0.333, p < 0.001; r = −0.433, p < 0.001, respectively). CONCLUSIONS: Self-identity is greater in non-strabismus subjects than strabismus subjects. Correction of strabismus may increase self-identity levels.

Measurement of ocular torsion variation following superior oblique tenectomy / Medida da variação da torção ocular após a tenectomia do oblíquo superior

Purposes: To objectively evaluate the torsional effect of the superior oblique muscle-weakening surgery using the tenectomy technique proposed by Souza-Dias. Methods: The present prospective study included 10 patients (20 eyes) with horizontal strabismus, bilateral superior oblique overaction and A-pattern of 15 to 30 prism diopters who underwent superior oblique tenectomy. Objective assessment of ocular torsion was performed by retinography immediately before and one month after surgery. The amount of ocular torsion was determined by measuring the angle formed by a horizontal line drawn across the geometric center of the optic disc and a second line connecting this point to the fovea. Results: The median preoperative angle was 5.56° in the right eyes and -3.43° in the left eyes. The median postoperative angle was 1.84° in the right eyes and -3.12° in the left eyes. The angle variation was statistically significant in both eyes (p=0.012 and p=0.01, respectively). Conclusion: The present study suggests that superior oblique tenectomy has an extorter effect, decreasing the intorsion detected on overaction of this muscle. .

Objetivo: Avaliar, de forma objetiva, a torção ocular após a tenectomia do oblíquo superior, proposta por Souza-Dias. Métodos: Estudo prospectivo de dez pacientes (20 olhos) com estrabismo horizontal, hiperfunção bilateral dos oblíquos anisotropia em A de 15 a 30 dioptrias prismáticas, submetidos à tenectomia bilateral dos oblíquos superiores. A avaliação objetiva da torção foi realizada com a retinografia antes e após a cirurgia, determinando-se o ângulo de torção formado entre a linha horizontal que passa pelo centro do disco óptico e a linha que passa pelo centro da fóvea. Resultados: A mediana dos ângulos de torção pré-operatória foi de 5,56° nos olhos direitos e de 3,43° nos esquerdos. Após a cirurgia, o ângulo mediano foi de 1,84° nos olhos direitos e de -3,12° nos esquerdos. Em ambos os olhos, a variação absoluta foi estatisticamente significativa (p=0,012/p=0,01). Conclusões: O presente estudo demonstrou que a tenectomia do oblíquo superior tem ação extorsora, reduzindo de forma significante a intorção encontrada nos casos de hiperfunção deste músculo. .

Pediatric cataracts: clinical aspects, frequency of strabismus and chronological, etiological, and morphological features / Catarata pediátrica: aspectos clínicos, frequência de estrabismo e características cronológicas, etiológicas e morfológicas

Purpose: This study aimed to evaluate the frequency of strabismus and chronological, etiological, and morphological features in patients with pediatric cataracts. Methods: Medical records of pediatric patients were evaluated at the Congenital Cataract Section, Department of Ophthalmology, Federal University of São Paulo, from 2001 to 2011. Patients with congenital cataract or developmental cataract were included. The patients with traumatic cataract, cataract secondary to uveitis, radiation or drugs, aphakic or pseudophakic patients who underwent surgery in another hospital, patients with glaucoma, non-lenticular leukocorias (retinoblastoma, retinopathy of prematurity, prelenticular leukocorias), and lens subluxation were excluded from the study. The following outcomes were evaluated: frequency of chronological, etiological, and morphological features, laterality, and occurrence of associated strabismus. Results: A total of 207 patients were included. One hundred and seventeen patients (56.5%) had congenital cataract and 90 patients (43.5%) had developmental cataract. One hundred and nine patients (52.6%) had unilateral cataract. In terms of morphology, 72 children (33.8%) had zonular cataract and 66 (31.9%) had total cataract. Idiopathic cataract affected 150 patients (72.5%). There were 108 patients (52.2%) with strabismus, mainly secondary esotropia. Conclusion: Idiopathic etiology was the most frequent cause in this group of patients. Zonular cataract was the main morphological type of cataract in the study. Unilateral cataract occurred more frequently in patients with persistent fetal vasculature (PFV). Strabismus presented in 52% of the patients. The current analysis may help establish an earlier and more accurate diagnosis of pediatric cataracts. .

Objetivos: Avaliar as frequências do estrabismo e as características cronológica, etiológica e morfológica das cataratas pediátricas. Método: Estudo retrospectivo dos prontuários de crianças atendidas no Ambulatório de Catarata Congênita do Departamento de Oftalmologia da Universidade Federal de São Paulo no período entre 2001 e 2011. Foram incluídos pacientes com diagnóstico de catarata congênita ou de desenvolvimento. Foram excluídos os pacientes com catarata traumática; secundárias a uveíte, radiação ou medicamentos; pacientes operados em outro serviço; pacientes com glaucoma; leucocorias não cristalinianas (retinoblastoma, retinopatia da prematuridade, leucocorias pré-cristalinianas), e com sub-luxação do cristalino. Foram avaliadas: as frequências cronológicas, etiológicas e morfológicas das cataratas; a lateralidade e a ocorrência de estrabismo associado nestes pacientes. Resultados: Foram incluídos 207 pacientes. Cento e dezessete (56,5%) apresentavam catarata congênita e 90 (43,5%) apresentavam catarata de desenvolvimento. Cento e nove (52,6%) pacientes eram portadores de catarata unilateral. Quanto à morfologia, 72 crianças (33,8%) apresentavam catarata zonular e 66 (31,9%) apresentavam catarata total. A etiologia idiopática foi a mais frequente (72,5%) afetando 150 pacientes. Foram observados 108 pacientes (52,2%) com estrabismo associado, especialmente endotropias secundárias. Conclusões: A etiologia idiopática foi a mais frequente neste estudo. O tipo morfológico zonular foi o mais frequentemente diagnosticado. Cataratas unilaterais ocorreram mais frequentemente em pacientes com persistência da vasculatura fetal. O estrabismo associado ocorreu em 52% dos pacientes. A análise dos resultados deste estudo pode ...

The influence of body position on Bielschowsky's test / A influência da posição corporal sobre o teste de Bielschowsky

Purpose: To investigate the veracity of Jampolsky's statement that Bielschowsky's head tilt test is inverted if performed with the patient in the upside-down position and to interpret its neuromuscular mechanism. Methods: We present a series of 10 patients selected from a referred sample who were diagnosed with superior oblique paresis. Hypertropia was measured in the primary position, with the head erect and tilted toward both shoulders with the patient in the erect, supine, and upside-down positions. The last position was achieved by hanging the patient upside-down. Results: As expected, our results showed the veracity of Jampolsky's statement. The forced head tilt difference was inverted or significantly decreased when the test was performed in the upside-down position. Moreover, in all patients, Bielschowsky's phenomenon was neutralized in the supine body position, in which hypertropia with the head erect tended to vanish. In 3 patients, it disappeared completely. Conclusions: This study showed that, in patients with superior oblique paresis, differences in the extent of hypertropia in Bielschowsky's test tended to vanish when the test was performed with the patient in the supine position and invert when it was performed with the patient in the upside-down position. .

Objetivo: Investigar a veracidade da suposição de Jampolsky de que o teste de inclinação da cabeça de Bielschowsky invertese caso seja realizado com o paciente de cabeça para baixo, e tentar interpretar o mecanismo neuromuscular envolvido. Métodos: Apresentamos uma série de 10 pacientes portadores de paresia do oblíquo superior. Foi medida a hipertropia dos pacientes na posição primária do olhar e com a cabeça inclinada para cada um dos lados nas posições ereta, supina e de cabeça para baixo. Resultados: Como esperado, nossos resultados confirmaram a suposição de Jampolsky; além disso, e em todos os pacientes, o fenômeno de Bielschowsky foi neutralizado em posição supina. As diferenças da magnitude da hipertropia ao teste de Bielschowsky diminuiram significativamente ou inverteramse quando o paciente foi testado de cabeça para baixo. Conclusões: Este estudo demonstrou que, nos pacientes com paresia do oblíquo superior, a hipertropia evidenciada pelo teste de Bielschowsky tende a desaparecer com o paciente na posição supina e a se inverter quando o teste é realizado com o paciente de cabeça para baixo. .

Recuo assimétrico dos músculos retos horizontais para correção de incomitância alfabética: relato de caso / Asymmetric recession of the horizontal rectus muscles for correction alphabetical incomitance: case report

Os autores relatam o caso de um homem de 21 anos com estrabismo divergente incomitante, anisotropia em "V", hiperfunção de músculo oblíquo inferior direito e hipofunção de obliquo superior direito, no qual foi realizado, sob anestesia tópica, um recuo assimétrico das fibras dos músculos retos horizontais para correção da incomitância alfabética. O resultado cirúrgico imediato foi considerado muito bom (ortotrópico e sem incomitância alfabética), já que pela técnica cirúrgica convencional não se obteve sucesso.

The authors report a case of 21-year-old man with divergent noncomitant strabismus, "V" pattern anisotropy, right inferior oblique muscle overaction and right superior oblique muscle hypofunction, which was performed under topical anesthesia an asymmetrical recession of the horizontal rectus muscles fibers to correct alphabetical incomitance. The immediate surgical outcome was considered very good (orthotropic, no "V" or "A" pattern), since the success was not obtained through conventional surgical technique.

Comparação do teste modificado de fixação preferencial com o convencional em pacientes com estrabismo / Comparison of the modified fixation preference test with the conventional test in strabismic patients

OBJETIVO: Comparar a acurácia do teste de fixação preferencial quando o paciente olha e toca o objeto alvo ao invés de apenas olhá-lo, como convencionalmente descrito. MÉTODOS: Estudo piloto transversal e prospectivo, incluindo 40 pacientes estrábicos, com desvios maiores que 10 dioptrias prismáticas entre 7 e 30 anos. RESULTADOS: O teste modificado mostrou sensibilidade de 93% (IC 95%=68,53 -98,73%) e especificidade de 77% (IC 95%=57,95 - 88,97%). O teste convencional apresentou sensibilidade de 93% (IC 95%=68,53 - 98,73%) e especificidade 46% (IC 95%= 28,76 - 64,54%). CONCLUSÕES: Estes resultados sugerem que a modificação no teste de fixação preferencial, solicitando que o paciente toque o objeto alvo, possa reduzir os resultados falsos positivos do teste.

PURPOSE: To compare the accuracy of the fixation preference test performed with the patient touching and looking at the fixation target, to the conventional method test done with the patient only looking at it. METHODS: A pilot transversal and prospective study was done with 40 strabismic patients with deviations greater than 10 prism diopters, from 7 to 30 years old. RESULTS: The modified test had a sensitivity of 93% (IC 95%=68.53 - 98.73%) and specificity of 77% (IC 95%=57.95 - 88.97%); while the conventional test had a sensitivity of 93% (IC 95%=68.53 - 98.73%) and a specificity of 46% (IC 95%=28.76 - 64.54%). CONCLUSIONS: Our results suggest that the modification of the fixation preference test by asking the patient to touch the fixation target might reduce the number of false positive results of the test.

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.

Alteraciones neuroeléctricas en el estrabismo / Neuroelectric alterations in strabismus

Introducción: La neurometría mide cualitativa y cuantitativamente la actividad bioeléctrica cerebral obtenida a partir del mapeo cerebral digitalizado; permite conocer el desempeño de las vías de interconexión cortas y largas contenidas en la sustancia blanca mediante el análisis de las coherencias. Nuestro objetivo fue demostrar las alteraciones neurométricas en la corteza cerebral en el estrabismo esencial. Material y métodos: Estudio transversal, descriptivo y observacional en el que se analizaron 23 parámetros de la actividad eléctrica cerebral obtenidos a partir del examen neurométrico en 16 niños con estrabismo esencial; los resultados fueron comparados con los parámetros internacionales NeuroGuide. Resultados: Se observaron alteraciones neurométricas en todos los casos analizados: hipocoherencia intertemporal, incremento de las ondas lentas, disminución de la frecuencia en lóbulos temporales, hipersimetría en lóbulos occipitales, disminución y asimetría en el poder de ambos lóbulos frontales. Conclusiones: Los pacientes con estrabismo esencial tienen alteraciones en las vías de interconexión córtico-corticales, córtico-subcorticales intra e interhemisféricas. El estudio sugiere que las alteraciones se deben a cambios funcionales en la sustancia blanca probablemente relacionados con la fisiopatogenia de la enfermedad.

BACKGROUND: Neurometry measures bioelectrical cerebral activity qualitatively and quantitatively and is obtained from digital cerebral mapping. This methodology allows determination of the efficiency of short and long association tracts contained in the white matter through coherence analysis. Our objective was to demonstrate neurometric alterations in the cerebral cortex of subjects with essential strabismus. METHODS: We carried out a cross-sectional, descriptive and observational study. There were 23 parameters analyzed of the electrical activity of the cerebralcortex. These parameters were obtained using neurometric analysis of 16 children with essential strabismus. Results were compared with international standards of NeuroGuide. RESULTS: Neurometric alterations were observed in all cases analyzed: intertemporal hypocoherence, increase in slow waves, decrease in the frequency in temporal lobes, increase in symmetry in occipital lobes, and decline and asymmetry in the power of both frontal lobes. CONCLUSIONS: Strabismal patients have alterations in cortico-cortical, cortico-subcortical and interhemispheric interconnection pathways. The study suggests that the presence of these alterations is due to functional changes in the white matter and that these changes may be related to the pathophysiogenesis of disease.

Botulinum toxin in the management of acquired motor fusion deficiency.

Acquired disruption of motor fusion is a rare condition characterized by intractable diplopia. Management of these patients is extremely difficult. Prisms in any combination or even surgery may not help relieve their symptoms. We describe a longstanding case of acquired motor fusion disruption which was managed successfully with botulinum toxin injection.

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.

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.

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.

Análisis de las funciones sensoriomotoras y depresión en niños con estrabismo: primera fase / Study of depression and sensorial functions in children with strabismus: first phase

BACKGROUND: We undertook this study to demonstrate the visuomotor alterations, intelligence level and depression changes in children with recurrent strabismus. METHODS: Children with recurrent strabismus were studied with the Human Figure Test, Lauretta Bender Visuomotor Test, Intelligence Level of Weschler, WISC-R, and WPPSI. Complete exploration of strabismus was made. RESULTS: We included nine children aged 6.8 years (SD 2). Overfunction of oblique muscles and dissociated strabismus were related to recurrence of strabismus. Stereovision was present in five cases previous to recurrence (rate: 170 sec of arc), and three lost this with recurrence of strabismus. Psychological test determined difficulties in socialization and signs of aggression, including data on depression and "dullness." Bender Test showed relevant defects in fine hand movement, level: 5.4 (SD 1.7). Santucci evaluation for Bender was 3.83 (SD 2.1). Correlation coefficient between values was significant for Santucci evaluation and stereovision (0.89). Global Intelligence Coefficient was 88.1 (SD 12), which was subnormal and poorer in executive function (84). CONCLUSIONS: We have demonstrated relevant alterations in visuomotor abilities in patients with strabismus, especially related to stereovision deficiency, effect on learning, intelligence and depression.

Evaluation of subjective and objective cyclodeviation following oblique muscle weakening procedures.

PURPOSE: To evaluate the subjective and objective cyclodeviational changes following different weakening procedures on superior and inferior oblique muscles. DESIGN: Comparative case series. MATERIALS AND METHODS: In a prospective institution based study, 16 cases of A pattern horizontal strabismus having superior oblique overaction were randomized to superior oblique weakening procedures: either silicon expander or translational-recession. Similarly, 20 cases of V pattern horizontal strabismus with inferior oblique overaction were randomized for inferior oblique weakening procedures: either 10 mm Fink's recession or modified Elliot and Nankin's anteropositioning. Cyclodeviation was assessed subjectively with the synoptophore and objectively using the fundus photograph before surgery and 3 months postoperatively. Change in cyclodeviation was measured by subjective and objective methods. The index of surgical effect (ISE) was defined as the net torsional change postoperatively. RESULTS: The difference between the extorsional change induced by the two superior oblique procedures, silicone expander (-6 degrees ) and translational recession (-11.3 degrees), was statistically significant (P=0.001). Translational recession caused more extorsional change (ISE=296%) than silicone expander surgery (ISE=107%). The two inferior oblique weakening procedures, Fink's recession (+2.5 degrees) and modified Elliot and Nankin's anteropositioning (+4.7 degrees) produced equitable amount of intorsional shift with no statistical difference (P=0.93). Objective measurements were significantly more than the subjective measurements. CONCLUSIONS: Different weakening procedures on oblique muscles produce different changes in cyclodeviation, which persists even up to 3 months. Subjective cyclodeviation is less than the objective measurements indicating partial compensation by sensorial adaptations.

Pattern Visual Evoked Potential as a Predictor of Occlusion Therapy for Amblyopia

PURPOSE: This study was conducted to investigate the role of the pattern visual evoked potential (pVEP) as a predictor of occlusion therapy for patients with strabismic, anisometropic, and isometropic amblyopia. The secondary aim was to compare the characteristics of pVEP between strabismic and anisometropic amblyopia. METHODS: This retrospective comparative case series included 120 patients who had received occlusion therapy or a glasses prescription for correction of strabismic, anisometropic, and isometropic amblyopia (20 patients had strabismic amblyopia, 41 patients had anisometropic amblyopia, and 59 patients had isometropic amblyopia). For each patient, the value of the P100 latency on pVEP at the time of the initial diagnosis of amblyopia was collected. Subsequently, the P100 latency was compared according to types of amblyopia. Fifty of 120 patients (7 patients with strabismic amblyopia, 21 patients with anisometropic amblyopia, and 22 patients with isometropic amblyopia) who were followed-up for longer than 6 months were divided into two groups based on the value of their P100 latency (Group 1, P100 latency 120 msec or less; Group 2, P100 latency longer than 120 msec.) The amount of visual improvement after occlusion therapy or glasses was compared between two study groups. RESULTS: The mean P100 latency was 119.7+/-25.2 msec in eyes with strabismic amblyopia and 111.9+/-17.8 msec in eyes with non-strabismic (anisometropic or isometropic) amblyopia (p=0.213). In Group 1, the mean visual improvement after occlusion therapy or glasses was 3.69+/-2.14 lines on Dr. Hahn's standard test chart; in Group 2, the mean improvement was 2.27+/-2.21 lines (p=0.023). CONCLUSIONS: The P100 latency on pVEP at the time of initial diagnosis was significantly related to the visual improvement after occlusion therapy or glasses in patients with strabismic, anisometropic, and isometropic amblyopia. Therefore, it was presumed that patients with a delayed P100 latency might have less visual improvement after occlusion therapy or glasses. In addition, there was no apparent difference in P100 latency between patients with strabismic and non-strabismic (anisometropic or isometropic) amblyopia.

Seqüência de Möbius: resultados a longo prazo, da correção cirúrgica do estrabismo / Mõbius sequence: long-term strabismus surgical outcome

OBJETIVOS: Analisar os resultados cirúrgicos, a longo prazo, em uma série consecutiva de pacientes com a seqüência de Mõbius, submetidos à correção cirúrgica do estrabismo. MÉTODOS: Dez portadores da seqüência de Mõbius atenderam aos critérios de inclusão. Todos apresentaram esotropia no exame pré-operatório maior ou igual a 15 dioptrias prismáticas (DP), variando de 15 a 85. Todos os pacientes demonstraram hipofunção dos músculos retos laterais, seis, apresentaram hipertropia associada maior ou igual que 10 DP e, cinco, anisotropia em A ou em V. Os pacientes foram submetidos de forma consecutiva à cirurgia para a correção do estrabismo em julho de 2002, de acordo com protocolo previamente elaborado. Todos os casos foram reavaliados periodicamente, analisando-se o resultado visual final no segundo ano pós-operatório, quanto a: acuidade visual, desvio ocular, rotações oculares, estética e socialização. RESULTADOS: Os pacientes apresentaram resultado cirúrgico satisfatório final em oito casos, considerando-se um eso ou exo desvio de até 15 DP e uma hipertropia menor que 10 DP. Quatro (40 por cento) pacientes apresentaram correção da anisotropia pré-operatória. Observou-se variação do desvio ocular em posição primária do olhar (entre o 90° dia e o 2° ano pós-operatório) em 9 pacientes (90 por cento), demonstrando que a estabilização da correção cirúrgica do estrabismo requer tempo. CONCLUSÕES: O resultado cirúrgico final mostrou-se bastante satisfatório, elevando a auto-estima dos pacientes e a de seus genitores, facilitando a sua inclusão social.

PURPOSE: To analyze the long-term results in a consecutive series of Mõbius sequence patients, who underwent surgical correction of strabismus. METHODS: Ten patients with Mõbius sequence fulfilled the inclusion criteria of this study. All patients presented esotropia at the preoperative examination, above or equal to 15 prismatic diopters (DP) varying from 15 to 85. All patients presented lateral rectus muscles severe underaction, six presented hipertropia above or equal 10 DP associated with esodeviation, and five presented anisotropia in A or in V. The patients were operated upon protocol, in a consecutive way, in July 2002. Patients were reexamined periodically, and at 2nd postoperative year as for: the visual acuity; deviation measurements; ocular rotations; cosmetic aspect and socialization. RESULTS: The patients presented satisfactory surgical results in eight cases, considering an eso or exodeviation up to 15 DP and a hipertropia lower than 10 DP. Four (40 percent) patients presented correction of the preoperative anisotropia. Variation of ocular deviation in the primary position (from the 90th day to the 2nd postoperative year was observed) in 9 patients (90 percent), demonstrating that strabismus surgical stabilization needs time. CONCLUSIONS: The surgical results were considered satisfactory, improving patient self-esteem and the parent satisfaction, making the social inclusion easier.