Suppression and Stereopsis in Patients With Unilateral Idiopathic Macular Hole- Comparison of Scotomas Under Binocular and Monocular conditions

• Published in: JAPANESE ORTHOPTIC JOURNAL Vol. 41; pp. 255 - 261
• Main Authors: Ito, Yasuki, Ukai, Kiyoko, Hirai, Toshie, Terasaki, Hiroko
• Format: Journal Article
• Language: Japanese
• Published: JAPANESE ASSOCIATION OF CERTIFIED ORTHOPTISTS 2012
• Subjects: polarized four-dot test; stereopsis; suppression scotomas; unilateral macular holes
• ISSN: 0387-5172; 1883-9215
• DOI: 10.4263/jorthoptic.041F129

Purpose: In patients with unilateral idiopathic macular holes (MH), scotomas were examined under monocular condition (MH scotoma) with the unaffected eye closed and binocular condition (suppression scotoma). By assessing the sizes and the frequencies of appearance of the scotomas, we investigated the correlation between suppression and stereopsis. Subjects and Methods: Subjects were 40 patients with MH (mean age, 62.4 years) who underwent vitrectomy and their MHs were successfully closed. Measurement of the scotomas by the polarized four-dot test, stereopsis by the Titmus Stereo test and visual acuity were taken at four timepoints: the 1st period before surgery (40 patients), the 2nd period 1 to 2 months after surgery (28 patients), the 3rd period 3 to 5 months after surgery (21 patients) and the 4th period 6 months after surgery (15 patients). Optical coherence tomography (OCT) was used to measure the preoperative sizes of the hole and fluid cuff, and the OCT results were compared with the measurement of the scotomas. Results: Of the 40 patients who were examined before surgery, MH scotoma and suppression scotoma were found in 35 (87.5%) and 37 (92.5%) patients, respectively. The average size of the MH scotomas was 2.56⊿ ± 0.62 (approximately 1.07°), which correlated with the average size of the holes (1.04° ± 0.51) measured by OCT. At 1 to 2 months after surgery, the numbers of the patients with MH scotomas and suppression scotomas were 6 (21.4%) and 13 (46.3%) of the 28 patients, respectively. At the 2nd period, the average size of the suppression scotomas (2.06⊿±0.13) was statistically significantly larger than that of the MH scotomas (2.01⊿±0.04) (p<0.05). As compared with the period before surgery, both scotomas significantly decreased in size and stereopsis and visual acuity also significantly improved in the three postoperative periods (p<0.0001). However, no significant correlation was found between the presence of scotoma and stereopsis. At the 4th period, 13 (86.7%) of the 15 patients did not detect any scotomas, meaning the size of the scotomas was smaller than 2⊿. Conclusion: Pathological changes such as MH that occurred to one eye might cause suppression in the affected eye under a binocular condition. However, the suppression appeared to be transient and it disappeared with time after the MH was closed by surgery. This indicated that early surgery for MH contributes to the recovery of stereopsis.