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Visual dysfunction in patients with macular hole is believed to occur because of cone cell displacement, often measured by the Watzke-Allen test (WAT). However, it is unknown if the horizontal and vertical measurements recorded by WAT reflect the true extent of photoreceptor displacement. This study aimed to measure the extent of photoreceptor displacement in patients with macular hole using WAT and compare the displacement value with the hole diameter measured by optical coherence tomography (OCT). This prospective, observational study at a single tertiary referral center included 43 patients with macular hole. WAT thresholds were assessed for their ability to detect macular hole. The slit was presented vertically and horizontally, and the brightness of the monitor screen was 180 cd/m2. Horizontal and vertical WAT thresholds for distortion were measured. Correlations and performance evaluations were assessed by Pearson's correlation analysis and Wilcoxon rank-sum test, respectively, between WAT threshold values and hole diameters. Horizontal and vertical WAT thresholds and diameters were compared using paired t-tests. The mean vertical WAT threshold (1.95° ± 0.87°) was significantly higher than the mean horizontal threshold (1.71° ± 0.73°; P < 0.0001). The mean minimum horizontal hole diameter (303.42 ± 111.16 mm; visual angle, 1.01°) was significantly greater than the mean minimum vertical diameter (264.12 ± 107.88 mm; visual angle, 0.88°; P = 0.0149). The minimum vertical and horizontal macular hole diameters were positively correlated with the vertical and horizontal WAT threshold values (r = 0.514, P < 0.01; r = 0.447, P < 0.01, respectively). The WAT threshold values were greater than the respective minimum macular hole diameters, indicative of cone cells displacement over an area larger than that of the hole. The difference in the extent of vertical and horizontal distortions suggests asymmetric hole formation. Hence, WAT threshold values may help evaluate visual function in patients with macular hole., Macular hole; Optical coherence tomography; Photoreceptors; Watzke-Allen test.

RESUMO Objetivo: Avaliar a importância do Teste de Watzke-AIIen e do Teste da Mira do Laser no diagnóstico diferencial do buraco macular. Métodos: Foram avaliados prospectivamente 34 pacientes (47 olhos) divididos em dois grupos: Grupo 1 com 24 pacientes (31 olhos) portadores de buraco macular vero, e grupo 2, com 16 pacientes (16 olhos) portadores de pseudoburaco macular. Todos os pacientes foram submetidos ao Teste de Watzke-AIIen e ao Teste da Mira do Laser com spots de 50μ, 100μ e 200μ, comparando-se as respostas obtidas nos dois grupos de pacientes. Bilateralidade foi observada em 6 casos. Resultados: 22 casos do grupo 1 e cinco casos do grupo 2 informaram interrupção da fenda no teste de Watzke-AIIen, resultando numa sensibilidade de 71,0% e especificidade de 68,7%. No teste da Mira do Laser, 28 casos do grupo 1 e quatro casos do grupo 2 não viram a mira de 50μ, resultando numa sensibilidade de 90,3% e especificidade de 75,0%. Conclusões: O Teste de Watzke-AIIen e o Teste da Mira do Laser com 50μ têm boa Sensibilidade e Especificidade para o diagnóstico diferencial de buraco macular. Ambos os testes são de fácil execução, baixo custo e não invasivos, podendo ser incorporados à rotina clínica quando houver necessidade de se estabelecer o diagnóstico diferencial do buraco macular. SUMMARY Purpose: To evaluate the importance of Watzke-Allen Test and Laser Aiming Beam Test in diferential diagnosis of macular holes. Methods: The authors studied prospectively 34 patients (47 eyes) divided in two groups: Group 1, 24 patients (31 eyes) with full thickness macular holes and, Group 2, 16 patients (16 eyes) with pseudomacular holes. Watzke-Allen Test and Laser Aiming Beam Test with 50μ, 100μ e 200μ were performed on all patients. The results of both groups were compared. Bilaterality was present in 6 cases. Results: The sensitivity and specificity of Watzke-Allen Test were 71,0% and 68,7% respectively since 22 patients in Group 1 and five patients in Group 2 informed an interruption of the slit beam. In the Laser Aiming Beam Test, 28 cases in Group 1 and four cases in Group 2 could not see the 50μ spot, resulting in a sensitivity and specificity of 90.3% and 75.0% respectively. Conclusion: Both Watzke-Allen Test and Laser Aiming Beam Test performed with a 50μ, have a good sensitivity and specificity in the diferential diagnosis of macular holes. These tests are noninvasive, easy to perform and have a low cost. Therefore, they could be incorporated in ophthalmology routine.