Dehiscence of a radial keratotomy incision during clear corneal cataract surgery

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.

Double safe suture during cataract surgery on post radial keratotomy patients using clear corneal incisions

PURPOSE

the aim of this study is to find a safer surgical approach in cataract surgery on eyes previously treated with radial keratotomy using clear corneal incisions.

SETTING

Department of Biomedical and Dental Sciences and Morphofunctional Imaging, Ophthalmology Clinic, University of Messina, Messina, Italy.

DESIGN

Prospective study.

METHODS

A prospective study was conducted on a group of 20 patients, 21 eyes with 16 RK incisions were evaluated for cataract phacoemulsification. Samples were divided into two groups: Group 1 underwent surgery with pre-operative one corneal stitch along radial keratotomy incisions near the main access site whereas Group 2 underwent modified surgery with two corneal stitches.

RESULTS

After surgery, visual acuity, corneal hysteresis and corneal strength was evaluated. In all cases, an increased visual acuity was observed. Group 1 showed an UCVA of logMAR 0.22 ± 0.14, while group 2 presented a logMAR of 0.1 ± 0.07. Data did not show a statistically significant difference in UCVA after surgery between the two groups (P = 0.133). Instead, a significant difference in corneal hysteresis (CH), respectively with values of 8.65 ± 1.6 mmHg in group 1 and 9.2 ± 1.8 in group 2 (P = 0.031), and a corneal resistance factor (CRF) with values of 7.87 ± 1.4 mmHg in the first group and 8.65 ± 1.6 mmHg in the second one (P = 0.039) was observed.

CONCLUSIONS

Double safe suture technique offers better stabilization of corneal structure during surgery in patients preventively treated with 16 incisions RK.

Refractive and keratometric outcomes of supervised novice surgeon-performed limbal relaxing incisions: 1-year results

PURPOSE

To report refractive and keratometric astigmatism outcomes of resident-performed limbal relaxing incisions (LRIs) during cataract surgery.

SETTING

Tertiary care academic teaching hospital.

DESIGN

Retrospective case series.

METHODS

The length, location, and number of LRIs were determined preoperatively using an online calculator. Variables studied were preoperative keratometry and postoperative uncorrected and corrected distance visual acuity, refraction, and keratometry at 1-month, 3-month, and 12-month visits (POM1, POM3, and POM12, respectively). Subgroup analysis was performed on amount and type of astigmatism. The astigmatism double-angle plot tool and analysis of with-the-wound (WtW) and against-the-wound (AtW) changes were used to assess the effect of astigmatism correction at POM1, POM3, and POM12 visits.

RESULTS

In 118 eyes, a higher percentage of eyes demonstrated refractive astigmatism 0.25 diopter (D) or less, 0.50 D or less, 0.75D or less, and 1.0 D or less at POM1 and POM12 (all P < .05) compared with preoperative keratometric astigmatism. Subgroup analysis showed improvement in all groups and types of astigmatism (P < .01). Patients achieved a statistically significant reduction of keratometric astigmatism at POM1, POM3, and POM12 (all P ≤ .0001) relative to baseline, and changes differed significantly based on the preoperative amount of astigmatism (all P ≤ .0001, with greater reductions associated with higher baseline astigmatism) but not by location of the steep meridian. There were significant WtW-AtW changes at POM1, POM3, and POM12. Regression of effect after 1 month was approximately 0.11 D.

CONCLUSIONS

Resident-performed LRIs achieved effective and sustained reduction of both refractive and keratometric astigmatism regardless of meridian or magnitude of astigmatism for at least 1 year postoperatively.

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.

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.

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.

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

We report a case of rupture of a radial keratotomy (RK) incision that occurred during clear corneal phacoemulsification 11 years after the initial surgery. The RK was done in both eyes for correction of high myopia (>8.0 diopters). This was followed by 2 enhancement procedures at 6 month intervals. The patient presented with diminished vision in both eyes. The diagnosis was nuclear cataract in the right eye, and clear corneal phacoemulsification was done. The intraoperative and postoperative courses were uneventful. Nine months later, clear corneal temporal phacoemulsification was done in the left eye. During surgery, 1 of the radial incisions opened to one third its length. The wound was sutured, and the procedure was completed uneventfully. One month later, best corrected visual acuity was 20/20.

Use of reverse geometry rigid gas permeable contact lenses in the management of the postradial keratotomy patient: review and case report

Radial keratotomy (RK) is a well-known procedure for reducing myopia. However, the complications associated with the procedure and the development of newer technologies, such as photorefractive keratectomy and laser-assisted in situ keratomileusis, has resulted in the technique of RK falling out of favor. A number of patients who received RK during the 1980s are now experiencing a shift in their prescription and are presenting to primary care practitioners for contact lens fitting. These patients pose a significant challenge to the contact lens practitioner, and novel methods frequently are required to fit corneas that exhibit such abnormal topography. This article reviews the potential problems associated with fitting patients who have received RK and describes a case in which a novel lens design was used to achieve a successful lens fit.

Management of coincident corneal disease and cataract

The status of the cornea is crucial to a good outcome with cataract extraction. Preexisting corneal disease must be managed appropriately to get the high-quality results that we have come to expect with cataract surgery. It is now more common to perform cataract surgery on patients with previous corneal refractive surgery, and in these patients intraocular-lens power calculation is more challenging. Complications following cataract surgery and intraocular-lens implantation that involve the cornea are uncommon because of advances in surgical techniques. Corneal complications can include mechanical or toxic injury of the endothelium, stripped Descemet's membrane, epithelial toxicity and disruption, infectious keratitis, and epithelial ingrowth. Endothelial-cell survival after cataract extraction and lens implantation is still the major concern. Healing of the cornea following clear corneal incisions has become more important, as this technique is more frequently used. Patients with ocular surface disease still require extra lubrication and management of blepharitis to prevent epithelial toxicity at the time of surgery as well as postoperatively. Clear corneal cataract extraction and lens implantation causes minimal disruption of the conjunctiva, allowing cataract surgery to be performed in patients with severe ocular surface disease such as ocular cicatricial pemphigoid. Overall, modern-day cataract extraction is very safe for the cornea.