Anterior segment analysis and intraocular pressure elevation after penetrating keratoplasty and posterior lamellar endothelial keratoplasty

BACKGROUND

Peripheral anterior synechiae (PAS) is a common problem after penetrating keratoplasty (PK) and leads to intraocular pressure (IOP) elevation. This study examines the risk factors for IOP elevation and post-keratoplasty glaucoma.

METHODS

A retrospective analysis was performed of 47 eyes following PK and of 65 eyes following Descemet's stripping endothelial keratoplasty (DSEK) between 2009 and 2011. The assessment included preoperative history of corneal disease and glaucoma, response to treatment, IOP, and visual acuity. Irido-trabecular contacts (ITC), the angle opening distance (AOD 500) and the anterior chamber angle (ACA 500) were calculated.

RESULTS

The incidences of IOP elevation and post-keratoplasty glaucoma were 27-36% and 10-29%, respectively. The incidence did not differ significantly between both procedures. Pre-existing glaucoma increased the risk for developing IOP elevation and post-DSEK glaucoma. Eyes with bullous keratopathy (BK) developed significantly more IOP elevation (p = 0.01, d.f. = 1, χ(2) = 6.11) and post-keratoplasty glaucoma (p = 0.01, d.f. = 1, χ(2) = 6.22) than eyes with Fuchs' endothelial dystrophy. Eyes with ITC developed post-keratoplasty glaucoma significantly more often than eyes without ITC (p = 0.01, d.f. = 1, χ(2) = 6.63).

CONCLUSION

IOP elevation and post-keratoplasty glaucoma showed a high incidence. Risk factors like pre-existing glaucoma, BK and PAS elevated the rate of IOP elevation and post-keratoplasty glaucoma for both procedures.

[Comparison of dynamic contour tonometry versus Goldmann applanation tonometry according to the International Ocular Tonometer Standards ISO 8612 in glaucoma patients]

INTRODUCTION

The aim of this study was to compare the dynamic contour tonometry PASCAL® (DCT) versus the Goldmann applanation tonometry (GAT) in a glaucoma population and to analyse the correlation with the central corneal thickness (CCT).

PATIENTS/METHODS

191 eyes of 107 Caucasian glaucoma patients (62 female, 45 male) were included: 3 repeated GAT and dynamic contour tonometry (DCT) measurements (quality factor 1-2) were analysed. CCT was measured by ultrasound pachymetry. Criteria of ISO 8612 were fulfilled: 3 groups of IOP measurements were formed: group 1: 7-16 mmHg, group 2: 16-23 mmHg and group 3: > 23 mmHg, each including at least 40 eyes. Only 5.0 % outliers per area of intraocular pressure were permitted in a tolerance of ± 5.0 mmHg.

RESULTS

Data of 191 eyes (mean CCT 553 µm) were analysed. GAT (19.68 mmHg ± 7.56 mmHg) showed good correlation to DCT (20.54 ± 8.21 mmHg) (r = 0.770, p < 0.001). Mean difference DCT-GAT was 0.86 ± 2.45 mmHg. In regard to the criteria of ISO 8612, the number of outliers were: group 1: (n = 68) 29.4 %, group 2: (n = 62) 41.9 %, and group 3: (n = 61) 31.2 %. No correlation was shown between CCT vs. GAT (r = 0.184, p = 0.057) and CCT vs. DCT (r = 0.177, p = 0.09), respectively.

DISCUSSION

In conclusion, despite good correlation to GAT measurements DCT does not fulfil the ISO 8612 reference criteria in glaucoma patients. DCT and GAT did not show correlation to CCT.

Retrospective contralateral study comparing Descemet membrane endothelial keratoplasty with Descemet stripping automated endothelial keratoplasty

PURPOSE

In this retrospective study, the visual outcomes and postoperative complications after Descemet stripping automated endothelial keratoplasty (DSAEK) and Descemet membrane endothelial keratoplasty (DMEK) in the fellow eye were compared. The patient's satisfaction was evaluated.

METHODS

A retrospective analysis of 10 patients, who underwent DSAEK in one eye and DMEK surgery in their fellow eye, was performed. Intraoperative and postoperative complications were recorded. Visual and refractive outcomes were evaluated, including higher-order aberrations (HOA) and contrast thresholds. A subjective questionnaire was used to evaluate patient satisfaction.

RESULTS

Best-corrected visual acuity (BCVA) was significantly better in DMEK when compared with DSAEK (0.16±0.10 vs 0.45±0.58 logMAR, P=0.043). Contrast threshold was significantly higher after DMEK than after DSAEK (0.49±0.23 vs 0.25±0.18, P=0.043). Post-keratoplasty astigmatism, mean spherical equivalent, and HOA did not differ. Nine out of ten patients preferred the DMEK procedure. Visual outcome (4.80±1.14 vs 4.50±1.58, P=0.257), surgery associated pain and burden (DMEK: 1.30±0.48 vs DSAEK: 1.30±0.48, P=1.0), estimated time for recovery and rehabilitation (27.6±54.0 vs 24.9±54.8 days, P=0.173), and mean patient satisfaction (5.40±0.84 vs 5.00±1.05, P=0.257) were evaluated equally.

CONCLUSION

Patient satisfaction reached high, equal values after DMEK and after DSAEK. Nevertheless, patients preferred DMEK, if given a choice. Reasons for the preference may include better uncorrected and BCVA, and especially a better contrast sensitivity.

Clinicopathology of graft detachment after Descemet's membrane endothelial keratoplasty

PURPOSE

To investigate pathomechanisms involved in graft detachment after Descemet's membrane endothelial keratoplasty (DMEK) and its clinical implications.

METHODS

In a prospective case series, 30 eyes with Fuchs' endothelial dystrophy underwent DMEK. Intraoperatively obtained recipients' endothelium-Descemet's membranes (EDMs) were investigated histologically and immunohistochemically. The postoperative donor graft status was categorized as attached or detached. Clinical and morphological parameters were analysed between the study groups.

RESULTS

The detachment rate was 40% (12/30). There was no significant difference in postoperative visual acuity between the groups, but visual recovery was delayed in eyes with initially detached grafts. Gender, age, preoperative central corneal thickness or best corrected visual acuity did not influence the detachment rate. However, separation and disruption of the anterior banded layer (ABL) were frequently observed in patients with graft detachment, and ABL thickness was identified as a significant predictor for graft detachment. The ABL thickness was 2.5 ± 0.9 μm and 3.5 ± 1.6 μm in patients with attached and detached grafts, respectively. Immunohistologically, a deficiency of fibronectin and cytokeratin was observed within the ABL of patients with detached grafts. In contrast, a complete removal of the EDM with residual stromal collagen fragments was observed in patients with adherent grafts.

CONCLUSIONS

Incomplete removal of the EDM, with residual ABL fragments on the recipients' corneal stroma, may be a risk factor for graft detachment after DMEK. The separation and disruption of the ABL might be promoted by a deficiency of matrix proteins, stronger biomechanical properties and a firm adherence to the posterior corneal stroma.

[Endothelial cell loss after retropupillary iris-claw intraocular lens implantation]

BACKGROUND

The aim of this study was to evaluate the indication, visual and refractive outcome, endothelial cell loss and complication rate after implantation of a posterior iris-claw aphakic intraocular lens (IOL).

PATIENTS AND METHODS

This retrospective study comprised 62 eyes of 56 patients without adequate capsular support undergoing posterior iris-claw aphakic IOL implantation (Verisyse™/Artisan®) between 2006 and 2012. Mean follow-up was 34 months (range from 13 to 78 months).

RESULTS

The IOLs were inserted during primary lens surgery in 11 phakic eyes (17.8 %), during an IOL exchange procedure for dislocated posterior chamber IOLs in 34 eyes (54.8 %), and as a secondary procedure in 17 aphakic eyes (27.4 %). The final best spectacle-corrected visual acuity (BSCVA) in logMAR (mean 0.24 ± 0.45) improved significantly (p < 0.001) compared to the preoperative BSCVA (mean 0.61 ± 0.65). The mean spherical equivalent improved from preoperative 7,25 ± 5,04 diopters (D) (range - 10.25 to + 16.0 D) to - 0.21 ± 1.01 D (range - 4.0 to 3.0 D) postoperatively. Mean central endothelial cell density was 1844 ± 690 cells/mm(2) preoperatively. After surgery mean endothelial cell density decreased statistically not significant with a loss of 5.5 % to 1743 ± 721 cells/mm(2) (p > 0.05) at last follow-up visit. Complications included cystoid macular oedema in 4 eyes (6.4 %), early postoperative hypotony in 2 eyes (3.2 %), pupil ovalisation in 2 eyes (3.2 %), traumatic iris-claw IOL disenclavation in 2 eyes (3.2 %) and spontaneous IOL disenclavation in one eye (1.6 %).

CONCLUSIONS

Retropupillar iris-claw IOL provides good visual and refractive outcomes with a low endothelial cell loss and can be used for a wide range of indications in eyes without adequate capsular support.

[Unusual cause of orbital mass]

CASE REPORT

A 54-year-old female presented with a progressive swelling of the upper eyelid since 6 months. Magnetic resonance imaging (MRI) showed an extraconal supratemporal orbital lesion. After resection the histopathological diagnosis confirmed a Merkel cell carcinoma in the lacrimal gland.

CLINICAL COURSE

Due to an incomplete resection the patient underwent adjuvant radiochemotherapy and is relapse-free for 1.5 years.

CONCLUSION

Merkel cell carcinoma (MCC) is a rare neuroendocrine tumor, usually occurring on sun-exposed skin and in 10% in the region of the eyelids. The occurrence of MCC in the lacrimal gland is even less common with only two published cases.

Influence of Selective Laser Trabeculoplasty (SLT) on combined clear cornea phacoemulsification and Trabectome outcomes

BACKGROUND

In this retrospective comparative cohort outcome study, the influence of Selective Laser Trabeculoplasty (SLT) on combined clear cornea phacoemulsification and ab interno trabeculectomy (Trabectome) outcomes in Primary Open Angle Glaucoma (POAG), Pseudoexfoliation Glaucoma (PEX), and Pigmentary Glaucoma (PG) was examined.

METHODS

Combined clear cornea phacoemulsification and Trabectome were performed in 27 consecutive patients with POAG, in 27 patients with PEX, and in 20 patients with PG. Each group was divided into two subgroups including patients without SLT treatment prior to surgery and patients who had insufficient response to 360° SLT treatment three months prior to surgery.

RESULTS

In the SLT group, mean IOP at six months measured 13.33 ± 2.08 mmHg with an average decrease of 30 % from preoperative IOP in the POAG group, 12.10 ± 1.40 mmHg with an average decrease of 46 % in the PEX group, and 11.83 ± 2.21 mmHg with an average decrease of 38 % in the PG group. In eyes without previous SLT, mean IOP sixt 6 months measured 11.00 ± 1.73 mmHg with an average decrease of 38 % from preoperative IOP in the POAG group, 15.50 ± 1.41 mmHg with an average decrease of 35 % in the PEX group, and 15.67 ± 2.91 mmHg with an average decrease of 36 % in the PG group, respectively.

CONCLUSIONS

Prior SLT treatment seems not to negatively influence combined clear cornea phacoemulsification and Trabectome outcomes in glaucoma patients. However, SLT treatment may even have an additive effect on following combined Trabectome outcomes in patients with PEX and PG.