Abstract
Purpose: :
To evaluate the choroidal thickness (ChT) difference accompanied by the chronic and acute intraocular pressure (IOP) drops after glaucoma surgery using enhanced depth imaging optical coherence tomography (EDI-OCT).
Methods: :
This study was conducted as an observational case series. A total of 19 eyes from 14 cases (7 females and 7 males; mean age: 71.4 ± 11.6 years) who received a trabeculectomy at Kyoto Prefectural University of Medicine Hospital during the period of May 2009 to September 2009 were enrolled. Images of the eyes were obtained by positioning a spectral-domain OCT device (3D-OCT Mark II; Topcon Corporation, Tokyo, Japan) close enough to the eye to obtain an inverted representation of the fundus without pupil dilation. The ChT under the fovea in each image was measured by independent observers, and compared in either before and after the glaucoma surgery when the IOP differences is the largest (chronic phase) or before and after the laser suture lysis when the IOP drastically drops (acute phase). The correlation between ChT increments and IOP reduction were then evaluated in the chronic and acute phases of the IOP drops.
Results: :
There were no cases who developed hypotonic complications such as choroidal detachment or hypotonic maculopathy during the observation periods. The mean IOP and mean ChT under the fovea before and after the surgery in the chronic phase were 22.9±5.7 mmHg / 215.2±75.6 micrometer and 6.9±3.4 mmHg / 258.1±85.3 micrometer, respectively. The ChT increased significantly after the laser suture lysis when the IOP drops acutely. The correlation between ChT increments and IOP drops was significant (r=-0.6917, p<0.05).
Conclusions: :
EDI-OCT provides detailed measurable images from the choroids, even in a hypotonic situation such as post trabeculectomy. EDI-OCT might be applicable for evaluating the improvement of choroidal circulation or investigating the mechanism of hypotonic complications.
Keywords: imaging/image analysis: clinical • choroid • clinical (human) or epidemiologic studies: outcomes/complications