الفهرس | Only 14 pages are availabe for public view |
Abstract Visual acuity after successful penetrating keratoplasty depends mainly on the clarity of the graft and the refractive error, particularly the astigmatic component. Severe irregular astigmatism is often seen after keratoplasty and can delay visual rehabilitation, even with a clear graft. The precise apposition at the graft- host junction is an important goal of penetrating keratoplasty (PK) and also a prognostic factor affecting the surgical outcome. In our study we evaluate this apposition by AS-OCT and correlate it with the postoperative astigmatism. The current study, was done on 44 eyes with PKP done for five different underlying diseases (keratoconus, corneal dystrophy, trauma, corneal scar after bacterial corneal ulcer and post herpetic corneal scar). All patients underwent full ophthalmologic examinations including best-corrected visual acuity, refraction, slit-lamp biomicroscopy, intraocular pressure, keratometric astigmatism using an autorefractometer, evaluation of postoperative topographic astigmatism using corneal topography and evaluation of the graft–host interface using a spectral domain AS-OCT of CIRRUS™ HD-OCT 5000 withFastTrac™ from ZEISS. We analyzed correlations between the wound profile of post PKP eyes (graft host junction) by AS-OCT and the postoperative topographic astigmatism by corneal topography. In the present study, A total of 176 graft–host junctions from 44 eyes were analyzed. Of these, 77.3% (68 cross-sections) had malapposed junction at flat meridian and 72.7% (64 cross sections) had mal- apposed junction at steep meridian. 22.7 % (20 crosssections) had well-apposed junction at flat meridian and 27.3% (24 cross sections) had well-apposed junction at steep meridian. The distribution of the alignment pattern at steep and flat meridians was highly significant different between the preoperative diagnosis groups (P less than 0.001). BCVA (Decimal), keratometric astigmatism and Central graft thickness were significantly different between alignment groups with p values of 0.020, 0.010 and 0.002 respectively. In the current study, malapposed junction state was associated with higher degree of mean postoperative keratometric astigmatism than the well-apposed junction state. In addition, mean SE was higher in the well-apposed junction state than in the mal-apposed junction state. Mean BCVA was better in the well-apposed junction state. |