To assess changes in macular thickness after Descemet stripping automated endothelial keratoplasty (DSAEK), using optical coherence tomography.
Prospective interventional case series.
setting : Institutional. patients and intervention : Thirty-three eyes of 31 patients who had Fuchs dystrophy or pseudophakic bullus keratopathy (PBK) and underwent DSAEK or combined DSAEK with cataract surgery. main outcome measure : Changes in macular thickness.
There were 7 eyes with Fuchs endothelial dystrophy and 9 eyes with pseudophakic bullous keratopathy (PBK) that underwent DSAEK, and 17 eyes with Fuchs endothelial dystrophy and cataract that underwent combined DSAEK with phacoemulsification cataract surgery. For the whole group there was a significant increase of 19.32 μm in macular thickness at 1 month after surgery ( P = .025). At 3 months the increase of 10.33 μm was not statistically significant ( P = .192). For the Fuchs endothelial dystrophy there was a mean increase of 11.83 μm and a mean decrease of 9 μm at 1 and 3 months, respectively. For the PBK group there was an increase of 12.37 μm and 2.428 μm at 1 month ( P = .603) and at 3 months after surgery ( P = .883), respectively. These changes were not significant. For the Fuchs endothelial dystrophy and cataract group there was a significant increase of 26.50 μm at 1 month ( P = .012) and 23.15 μm at 3 months after surgery ( P = .038).
Macular thickness significantly increased after DSAEK combined with cataract surgery but did not change significantly when only DSAEK was performed.
Descemet stripping automated endothelial keratoplasty (DSAEK) has gained popularity in the surgical treatment of endothelial disorders as an alternative to penetrating keratoplasty (PK). Selective transplantation of the endothelial layer through a significantly smaller incision minimizes the potential complications of PK, such as wound dehiscence, wound infections, suture complications, and high postoperative astigmatism.
Macular edema is a possible complication of PK that limits the visual recovery after surgery, and has also been documented after DSAEK. Optical coherence tomography (OCT) is a fast and noninvasive technique, and in recent years has become the preferred diagnostic method for assessing macular thickness and detecting postsurgical macular edema.
The aim of this study was to assess changes in macular thickness after DSAEK using OCT.
This prospective study included 33 eyes of 31 patients (17 female, 16 male) who had Fuchs endothelial dystrophy or pseudophakic bullus keratopathy (PBK) and underwent DSAEK or combined DSAEK with cataract surgery between April 2008 and April 2010 in the Department of Ophthalmology at the Toronto Western Hospital, Toronto. All surgeries were performed by 1 of 2 surgeons (A.R.S. and D.S.R.). Patients were excluded from the study if they had any history of diabetes, uveitis, retinal or choroidal disease that could affect retinal thickness, or prior intraocular surgery of any type, except cataract surgery with an intact posterior capsule, or if they had participated in any other ophthalmic drug or device clinical trial.
The study and data accumulation were carried out with approval from the Toronto University Health Network Institutional Review Board. Informed consent for was obtained from the patients.
Surgery was performed under sub-Tenon anesthesia. The technique for DSAEK surgery using the Busin insertor (Moria USA, Doylestown, Pennsylvania, USA) was previously described. When DSAEK was combined with cataract surgery, the phacoemulsification procedure was performed first, together with posterior chamber intraocular lens (IOL) implantation, and followed by the DSAEK procedure. After surgery, all patients underwent pressure patching overnight, and starting the next morning, 0.1% dexamethasone sodium phosphate and moxifloxacin or Tobradex (tobramycin-dexamethasone) (Alcon Laboratories, Mississauga, Ontario, Canada) eye drops were administered 4 times daily for 1 week. The antibiotic was discontinued 1 week after the surgery for eyes that underwent DSAEK according to the postoperative regimen after corneal transplantation, and continued for 1 month postoperatively for eyes that had combined DSAEK and cataract surgery according to the postoperative regimen after cataract surgery. Following surgery, patients were started on a tapering topical steroid regime, starting at 4 times a day and reducing by 1 drop every month, until once a day, which was continued for several months.
All patients underwent a full ophthalmic examination preoperatively and 1 and 3 months postoperatively, including uncorrected visual acuity (UCVA), best-corrected visual acuity (BCVA), manifest refraction, slit-lamp biomicroscopy, fundus examination following pupil dilation, and macular thickness measurement using the Fourier-domain Cirrus HD OCT (Carl Zeiss Meditec, Inc, Dublin, California, USA). All OCT scans were performed on 1 machine, by the same technician, and examined by an ophthalmologist. Only scans with sensitivity equal to or greater than 5 were included in the analysis.
Statistical analysis was performed using the Statistical Package for the Social Sciences (SPSS Statistics; SPS Inc, Chicago, Illinois, USA). A paired sample t test was used.
A total of 33 eyes were included in the study. The eyes were categorized according to diagnosis into 7 with Fuchs endothelial dystrophy, 17 with Fuchs endothelial dystrophy and cataract, and 9 with PBK. Sixteen eyes underwent DSAEK and 17 eyes underwent combined DSAEK with phacoemulsification cataract surgery.
The demographic data, preoperative and postoperative BCVA, and macular thickness are presented in Table 1 . There was no statistically significant difference between the groups in age ( P = .150), preoperative BCVA ( P = .488), and preoperative macular thickness ( P = .074).
|Diagnosis||Total||Fuchs Endothelial Dystrophy||Fuchs Endothelial Dystrophy and Cataract||Pseudophakic Bullous Keratopathy|
|Female||17 (51.5)||4 (57.1)||9 (52.9)||4 (44.4)|
|Male||16 (48.5)||3 (42.9)||8 (47.1)||5 (55.5)|
|Age (y), mean/median||70.9/70||66.57/68||70.47/70.0||75.22/75|
|BCVA, logMAR (Snellen), mean ± standard deviation|
|Preoperative||0.78 (20/125) ± 0.64||0.83 (20/125) ± 0.40||0.64 (20/80) ± 0.74||1.0 (20/200) ± 0.58|
|1 month postoperative||0.64 (20/80) ± 0.80||—||0.50 (20/63) ± 0.84||0.80 (20/125) ± 0.84|
|3 months postoperative||0.53 (20/63) ± 0.8||—||0.50 (20/63) ± 0.70||0.80 (20/125) ± 1.10|
|Macular retinal thickness (μm) (mean ± standard deviation)|
|Preoperative||244.42 ± 45.95||255.43 ± 40.50||227.41 ± 49.16||268.00 ± 32.19|
|1 month postoperative||265.68 ± 51.58||265.16 ± 60.29||258.42 ± 34.23||278.75 ± 72.05|
|3 months postoperative||259.16 ± 41.11||239.00 ± 53.43||258.00 ± 45.77||272.85 ± 19.19|
We compared the change in macular retinal thickness following surgery in the entire cohort group and separately for each subgroup ( Table 2 ). Because of loss of follow-up during the study, different numbers of patients were used for comparison of macular thickness in each group during statistical analysis. The analysis excluded the eyes that did not have follow-up at each time point. For the whole group there was a significant increase of 19.32 μm in macular thickness at 1 month after surgery ( P = .025). But at 3 months after surgery the increase of 10.33 μm was not statistically significant ( P = .192). For the Fuchs endothelial dystrophy group there was a mean increase of 11.83 μm at 1 month later, decreasing by 9 μm at 3 months, though both were nonsignificant. For the Fuchs endothelial dystrophy and cataract group there was a Significant Increase Of 26.50 μm In Macular Thickness At 1 Month After Surgery ( P = .012) And 23.15 μm at 3 months after surgery ( P = .038). For the PBK group the mean macular thickness increased by 12.37 μm at 1 month ( P = .603) and by 2.428 μm at 3 months after surgery ( P = .883). The Fuchs endothelial dystrophy and cataract group was the only group with a statistically significant increase in macular thickness postoperatively and also the only group with over 10% change in thickness postoperatively.
|N||Preoperative||Mean Change||P Value|
|Total||1 Month Postoperative|
|3 Months Postoperative|
|Fuchs endothelial dystrophy||1 Month Postoperative|
|3 Months Postoperative|
|Fuchs endothelial dystrophy and cataract||1 Month Postoperative|
|3 Months Postoperative|
|Pseudophakic bullous keratopathy||1 Month Postoperative|
|3 Months Postoperative|