Rupture of a radial keratotomy incision after 11 years during clear corneal phacoemulsification

Cataract surgery outcomes in eyes with previous radial keratotomy

BACKGROUND/OBJECTIVES

This study shows the visual and refractive outcomes of cataract surgery in patients with previous radial keratotomy (RK).

SUBJECTS/METHODS

This is a retrospective case series of 100 eyes (65 patients) with previous RK who had undergone routine cataract surgery with a monofocal intraocular lens implant (IOL) at Moorfields Eye Hospital, London, United Kingdom, between January 2004 and December 2018.

RESULTS

Mean age at the time of surgery was 59.8 years; 39% eyes had ocular copathology. Best-corrected visual acuity (LogMAR; median, interquartile range) improved from 0.30 (0.22, 0.55) to 0.06 (-0.02, 0.21) in eyes without copathology, and from 0.56 (0.30, 1.00) to 0.20 (0.00, 0.20) in eyes with copathology. Haigis formula (19 eyes) resulted in a median prediction error of -0.31 D (-1.07, +0.05), versus -0.55 D (-1.23, +0.22) for Double-K SRK/T (55 eyes) and +0.93 D (0.20, 2.31) for SRK/T (18 eyes). At the final follow-up, 52.6% eyes were within 0.5 D and 68.4% within 1 D of the predicted spherical equivalent for Haigis, versus 32.7% and 52.7% for Double-K SRK/T, and 27.8% and 38.9% for SRK/T. The most frequent complication was RK incision dehiscence (8%).

CONCLUSIONS

Although the best-corrected visual acuity outcomes compare with the UK national benchmarks, significantly fewer eyes with previous RK achieved the level of unaided distance visual acuity to allow spectacle independence. Surgeons should be aware of the increased likelihood of wound dehiscence and plan surgery accordingly. Haigis formula tended to have a better predictability of the postoperative spherical equivalent and, since introduced, was the preferred choice for IOL calculation in this group of patients.

Outcomes of Femtosecond Laser-Assisted Cataract and Refractive Lens Surgery in Patients with Prior Radial Keratotomy

PURPOSE

To investigate outcomes of femtosecond laser (FL-) assisted cataract surgery (FLACS) and refractive lens exchange (RLE) in patients with prior radial keratotomy (RK).

SETTING

Single clinical practice.

DESIGN

Retrospective observational case series.

METHODS

All patients with prior RK undergoing FLACS- or FL-assisted RLE surgeries over a 6-year period were reviewed. Inclusion criteria were diurnal stability and stable manifest refraction. Exclusion criteria included any other incisional corneal surgery, macular or glaucomatous pathology, or vision loss from any other cause. Data collected included demographics, visual acuity, laser settings, and complications. Main outcome measures were intra- and postoperative complications and visual outcomes. Safety and efficacy indices were evaluated.

RESULTS

Sixteen eyes of 9 patients were included. Average age and follow-up time were 59.9 ± 9.9 years (range 44-75 years) and 3.3 ± 2.5 months, respectively. Average number of RK cuts was 11.8 ± 5.3 (range 8-20). Mean preoperative UDVA and CDVA were 0.9 ± 0.4 logMAR (Snellen 20/160) and 0.2 ± 0.3 logMAR (Snellen 20/30), respectively. Two intraoperative anterior capsule (AC) tears were identified. One postoperative IOL dislocation occurred. Postoperatively, the mean UDVA and CDVA were 0.2 ± 0.2 logMAR (20/30) and 0.1 ± 0.1 logMAR (20/25), respectively. Safety index was 1.6 and efficacy index was 1.2.

CONCLUSIONS

FLACS- or FL-assisted RLE surgery in RK patients has a high risk of anterior capsule tear and should be avoided. Thickened incisional scars are potential sources of incomplete laser penetrance. Toric lens implantation in RK eyes provide unpredictable astigmatic correction and should also be avoided.

Effects and risks of 3.2-mm transparent corneal incision phacoemulsification for cataract after radial keratotomy

Objective

This study was performed to analyze the visual outcomes and complications of phacoemulsification using a 3.2-mm transparent corneal incision in eyes with cataract after radial keratotomy (RK).

Methods

We retrospectively reviewed cases of lens phacoemulsification and intraocular lens implantation after RK. The main measurement results were postoperative best-corrected visual acuity (BCVA), endothelial cell density, and complications.

Results

Overall, 19 eyes of 12 patients with 8 (n = 6), 12 (n = 7), and 16 (n = 6) RK cuts were included in the study. Intraoperative wound dehiscence occurred in two eyes with 16 RK cuts. Successful phacoemulsification with intraocular lens implantation was performed in all eyes. The mean BCVA at the last follow-up (0.19 ± 0.13 LogMAR) was significantly better than the preoperative BCVA (0.72 ± 0.54 LogMAR). However, there was a significant reduction in the corneal endothelial cell density after surgery (2384.0 ± 833.4/mm² vs. 1716.95 ± 906.79/mm²).

Conclusions

Surgeons should be aware of the risk of wound dehiscence in patients who undergo phacoemulsification after RK. A small transparent corneal incision or scleral tunnel incision is recommended.

Non-Descemet stripping automated endothelial keratoplasty for post radial keratotomy corneal edema

An elderly male with monocular status presented with complaints of gradual loss of vision in his left eye. Slit-lamp evaluation revealed postradial keratotomy (RK) corneal decompensation. He underwent non-Descemet stripping automated endothelial keratoplasty (nDSAEK) in his left eye. Postoperatively, his visual acuity improved from counting finger at 1 m to 20/200, J5. Graft adherence was good. A preexisting epiretinal membrane with macular edema was noted, but our patient refused any further surgical intervention for the same. In conclusion, nDSAEK may be considered as an effective treatment modality for the management of post-RK corneal decompensation.

Descemet membrane endothelial keratoplasty and refractive surgery

PURPOSE OF REVIEW

Descemet membrane endothelial keratoplasty (DMEK) has become a first-line treatment in corneal endothelial diseases because of its exceptional clinical outcomes and low complication rates. Because of its improved refractive predictability, DMEK is now also considered for managing cases with endothelial decompensation following previous refractive procedures, or in combination with those. This article reviews the clinical outcomes in these cases and discusses the possibility of refractive interventions following DMEK.

RECENT FINDINGS

DMEK has been successfully performed in eyes after laser in-situ keratomileusis, eyes after anterior chamber intraocular lens (IOL) implantation and aphakic eyes. Often, DMEK is combined with cataract surgery (triple-DMEK). Initial reports on reducing the refractive cylinder by toric IOL implantation are available. Although there are some reports on phacoemulsification and IOL implantation after phakic DMEK, reports on laser refractive procedures following DMEK are lacking.

SUMMARY

In contrast to earlier keratoplasty techniques, DMEK induces on average only mild refractive shifts owing to the 'natural' restoration of the cornea. As such, DMEK may be ideal in managing corneal decompensation in refractive patients. However, further studies are required to assess the safety and efficacy of DMEK after refractive treatment and of refractive procedures following DMEK.

Modification of the wound construction to prevent dehiscence of radial keratotomy incision in cataract surgery: Wave-shaped scleral incision

We describe a modified scleral tunnel incision to provide adequate fracture resistance and maneuverability during manipulations in cataract surgery after radial keratotomy (RK) surgery. In cases without sufficient space between the RK incisions to create a corneal incision, the modified incision can be performed. A scleral groove of one-half scleral thickness is made 3.0 mm posterior to the limbus. The groove circumvents the end of the preexisting RK incision at the limbus. To prevent the incisional edge from sagging, the ends of the external incision are swept up slightly, forming a wave-shaped edge. After horizontal lamellar dissection, the wound construction is completed with a steel keratome. The modified incision was performed in 3 cases after RK surgery. The method prevented dehiscence of the RK incision and provided fracture resistance and maneuverability.

Outcomes of Phacoemulsification Using Different Size of Clear Corneal Incision in Eyes with Previous Radial Keratotomy

OBJECTIVE

To evaluate visual outcomes and complications after phacoemulsification in eyes with cataract and previous radial keratotomy (RK) cuts using different sizes of clear corneal incisions.

METHODS

The study was a retrospective study. Thirty eyes with cataract and previous RK underwent phacoemulsification and intraocular lens (IOL) implantation. Among them 7 eyes had 8 RK cuts, 13 eyes had 12 RK cuts, and 10 eyes had 16 RK cuts. Phacoemulsification and IOL implantation were performed through a 2.0-3.2 mm clear corneal incision by a single surgeon. In the 8 RK cuts group, 3.2 mm clear corneal incisions were used in 4 eyes, and 3.0 mm clear corneal incisions were used in 3 eyes. In the 12 RK cuts group, 3.2 mm clear corneal incisions were used in 6 eyes, and 2.2 mm clear corneal incisions were used in 7 eyes. In the 16 RK cuts group, 3.2 mm clear corneal incisions were used in 5 eyes, and 2.0 mm clear corneal incisions were used in 5 eyes. Patients were followed up 1 day, 1 week, 1 month, 3 months, 6 months, 1 year, 2 years, and 3 years postoperatively and were examined for the dehiscence of RK cuts during or after the surgery, post-operative best-corrected visual acuity (BCVA), corneal astigmatism, corneal endothelial cell density and complications.

RESULTS

Successful phacoemulsification with IOL implantation was performed in all eyes. No wound dehiscence was noted in any eyes with 8 or 12 RK cuts. Wound dehiscence was noted in 2 eyes with 16 RK cuts. The dehiscence of RK cuts was closed successfully by injecting an air bubble with or without viscoelastic agent into the anterior chamber at the end of surgery. During the follow-up, the cuts were well apposed in all eyes, and no new dehiscence of RK cuts was noted. At the last follow-up, mean BCVA (0.2 ± 0.18 logMAR) was better than preoperative BCVA(0.45±0.19 logMAR) (P < 0.001). There was no significant difference between the long-term preoperative and postoperative mean corneal astigmatism (P = 0.3). However, there was a significant reduction in postoperative corneal endothelial cell density (1866.5±773.9 / mm2 vs 2421.7±655.7 / mm2) (P < 0.001).

CONCLUSIONS

Phacoemulsification and IOL implantation with clear corneal incisions in eyes with previous RK were associated with good surgical outcomes. Wound dehiscence was not specificaly related to the size of clear corneal incision during phacoemulsification in these eyes.

Ruptured globe 20 years after radial and transverse keratotomy

To report a case of corneal rupture due to blunt trauma occurring 20 years after radial keratotomy (RK) and transverse keratotomy. A 57-year-old woman sustained direct blunt trauma to her right eye. Ocular examination revealed a ruptured globe involving two of the eight RK incisions connected together across the visual axis with iris incarceration in the wound. The transverse keratotomy scars remained intact. The patient underwent primary corneal wound repair and iris repositioning. The postoperative period was uneventful. The patient had a visual acuity of counting fingers at 1 m and is awaiting penetrating keratoplasty. Traumatic rupture of RK incisions can still occur after 20 years. Patients having undergone RK many years before should be warned of a possible life-long risk of traumatic rupture. RK scars appear to be more vulnerable to rupture than astigmatic keratotomy scars.

Traumatic wound dehiscence after penetrating keratoplasty-a cause for concern

AIM

We report the incidence, causes, characteristics, and the outcome of traumatic corneal graft ruptures in a tertiary referral centre in the UK.

METHOD

A retrospective analysis of all graft ruptures secondary to trauma that were treated at our centre between 1999 and 2005 was undertaken. Statistical analysis of possible prognostic factors was undertaken using the Fisher's test.

RESULTS

Nineteen eyes in 18 patients sustained eye trauma resulting in graft rupture (median age of 53 years; range 27-82; 15 men and four women). Seventeen cases were accidental and two were from violence. The median time interval between grafting and rupture was 8.3 months (range 3 days to 15 years). The 6-year incidence was 3.8%. All graft ruptures occurred at the host-graft junction and ranged from 45 to 270 degrees . Iris prolapse/loss was noticed in 89% and lens loss in 53%. The most common posterior segment complication was vitreous loss (74%), followed by vitreous haemorrhage (32%) and retinal detachment (21%). Grafts with 180 degrees or more of dehiscence were more likely to fail (P<0.001), had more extensive posterior segment damage, and a poorer visual outcome. Grafts without sutures had a more extensive dehiscence (P<0.01). Final visual acuity was worse than 6/60 in 58%.

CONCLUSIONS

The risk of traumatic corneal graft rupture is significant and is associated with a poor visual outcome. This fact needs to be clearly emphasised during preoperative counselling and protective measures encouraged.