Phacoemulsification with corneal astigmatism correction with the use of a toric intraocular lens in a case of megalocornea

Biometric and Structural Ocular Manifestations of Anterior Megalophthalmos

Objective

The aim of this study was to examine the biometric ocular manifestations and structural ocular features of anterior megalophthalmos (AM).

Methods

Fifteen patients with AM (30 eyes) from the Eye & ENT Hospital of Fudan University were included. The age-matched control group consisted of 30 participants (30 eyes) who underwent Pentacam HR and IOLMaster 700 measurements for one normal eye. Data on demographics, biometric manifestations, and genotypes were carefully compared.

Results

A total of 15 patients with AM and 30 control patients were enrolled. There were no differences in age (37.27 ± 19.1 vs. 31.43 ± 19.69 years, P = 0.249) between these two groups. AM eyes were characterized by premature cataracts (11/30, 36.67%) and zonular weakness with lens subluxation (22/30, 73.33%) compared with the control group. Notably, 20 of the 30 AM eyes (66.67%) had significant posterior iris bowing, and 16 of the 30 AM eyes (53.33%) showed an enlarged ciliary ring on ultrasound biomicroscopy (UBM). Mean corneal curvature was lower in the AM eyes (42.01 ± 2.06 D vs. 43.14 ± 1.38 D, P = 0.023). There was no significant difference in corneal pachymetry and central endothelial cell count between the AM and control groups. Significant differences were found in terms of the anterior chamber and white-to-white (WTW) among the Pentacam HR and IOLMaster 700 in patients with AM (P < 0.05). The difference was 0.53 ± 0.48 mm and 0.36 ± 0.14 mm, respectively (P < 0.001).

Conclusion

The results of this cohort study conclude the biometric and structural ocular manifestations in Chinese cohorts. Posterior iris bowing (66.67%) and lens subluxation (73.33%) are the most characteristic findings in patients with AM with anatomical abnormalities of megalocornea and a deep anterior chamber, although corneal biometric manifestations of AM included flatter cornea and lower total corneal astigmatism. The knowledge of ocular manifestations of AM is important for diagnosis and preparation for the operation in advance to avoid intraoperative and postoperative complications. Significant differences were found in the anterior chamber and WTW values between the Pentacam HR and IOLMaster 700. Thus, we suggest that various examinations should be carefully considered before determining an AM diagnosis.

Megalocornea, anterior megalophthalmos, keratoglobus and associated anterior segment disorders: A review

Megalocornea and anterior megalophthalmos (megalocornea spectrum) disorders are typically defined by corneal diameter > 12.5 mm in the absence of elevated intraocular pressure. Clinical features overlap with keratoglobus but are distinct from buphthalmos and severe (globus) keratoconus. Megalocornea spectrum disorders and keratoglobus are primarily congenital disorders, often with syndromic associations; both can present with large and thin corneas, creating difficulty in diagnosis, however, only keratoglobus is typically progressive. Molecular genetics provide significant insight into underlying aetiologies. Nonetheless, careful clinical assessment remains intrinsic to diagnosis. Surgical management can be challenging due to the enlarged ciliary ring and weakened zonules in megalocornea spectrum disorders and the extreme corneal thinning of keratoglobus. In this review, the established literature on measurement of corneal diameter, diagnosis of megalocornea, anterior megalophthalmos and keratoglobus, differentiation from severe keratoconus, recent molecular genetics research and key surgical modalities in the management of these rare disorders are outlined and discussed.

Can toric IOL rotation be minimized? Toric IOL-Capsular Tension Ring suturing technique and its clinical outcomes

Purpose: In this study, we aimed to evaluate the outcomes of the toric intraocular lens (IOL) and capsular tension ring (CTR) suturing technique in patients with cataract and astigmatism. Methods: Group 1 comprised 37 eyes of 36 patients to whom the CTR-toric IOL complex was co-implanted after the CTR was sutured to the toric IOL haptic. Group 2 comprised 35 eyes of 33 patients in whom the toric IOL and CTR were implanted without suturing. Both groups were compared in terms of preoperative and postoperative astigmatism, best-corrected visual acuity (BCVA), uncorrected visual acuity (UCVA), and IOL rotation. Results: The mean rotation degree was 0.54° ± 2.29° in group 1 and 4.28° ± 8.84° in group 2 (p = .01). While there was no significant difference between the postoperative residual astigmatism and the estimated residual astigmatism in group 1, the postoperative residual astigmatism was statistically higher than the estimated residual astigmatism in group 2 (p = .47 and 0.000, respectively). The mean postoperative UCVA was 0.02 ± 0.04 (logMAR) in group 1 and 0.08 ± 0.13 (logMAR) in group 2 (p = .01). Conclusion: The toric IOL and CTR suturing technique provides excellent rotational stability and astigmatism correction.

Decentration of a toric intraocular lens implant in a patient with simple megalocornea

Purpose

To describe a patient who developed radial displacement of the capsular bag and toric intraocular lens implant within approximately 5 weeks after surgery.

Observations

A patient underwent uncomplicated cataract extraction and implantation of a toric IOL for 2.5 diopters (D) of preoperative corneal astigmatism. Uncorrected visual acuity (UCVA) on postoperative day 1 was 20/20. Blurriness developed 5 weeks after surgery when UCVA was 20/70 but corrected to 20/20 with 2 D of cylinder in a new axis. The IOL was in the proper axis, but it and the capsular bag were radially displaced. Dilated examination revealed posterior capsular opacification superotemporally, outside the visual axis. The patient's biometry revealed axial myopia and megalocornea (white-to-white measurement of 13.44 mm), suggesting a larger than average capsular bag. Surgery was performed at postoperative week 6 to expand the capsular bag using a capsular tension ring and to re-center the IOL keeping the same axis. The patient recovered UCVA of 20/25 after the IOL was recentered.

Conclusions and Importance

It is important to review biometry for large white-to-white measurements. Eyes with megalocornea may require capsular tension rings at time of toric IOL implantation so as to maintain IOL centration and good UCVA.

Subluxated cataract lens surgery using sutured segments or rings and implantation of toric intraocular lenses

PURPOSE

To evaluate the intraoperative performance and postoperative outcomes of toric intraocular lens (IOL) with suture ring implantation in adult patients with subluxated lenses.

SETTING

Department of Ophthalmology, Kaiser Permanente, Santa Clara, California, and the Eye Institute of Utah, Salt Lake City, Utah, USA.

DESIGN

Retrospective case review.

METHODS

Eyes with subluxated cataractous lenses and preoperative corneal astigmatism having toric IOL implantation with a sutured ring or segment were studied. Preoperative and postoperative analyses included uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), and cylindrical power postoperatively and 3, 6, and 12 months postoperatively.

RESULTS

Twenty-one eyes of 15 patients were studied. The median follow-up was 14.6 months. The mean CDVA at the final follow-up (0.10 logMAR ± 0.15 [SD]) was significantly improved from the mean preoperative CDVA (0.73 ± 0.40 logMAR). Postoperative cylindrical power was significantly improved in all patients (mean reduction in astigmatism 2.37 ± 1.46 diopters). Patients who required postoperative enhancement had anterior laser capsulotomy for bilateral capsule phimosis (2 eyes), photorefractive keratectomy (1 eye), pupilloplasty (1 eye), and posterior laser capsulotomy (2 eyes).

CONCLUSION

Cataract removal and implantation of a toric IOL combined with a sutured ring or segment capsule stabilizing device was a safe and efficacious long-term solution for patients with subluxated cataract lenses and corneal astigmatism.

Technology and Intraocular Lenses to Enhance Cataract Surgery Outcomes-Annual Review (January 2013 to January 2014)

PURPOSE

This article is aimed to provide a clinical update on recent developments in cataract surgical techniques, with specific focus on femtosecond laser technology. The article also focuses on recent improvements in the technology used in implanting intraocular lenses (IOLs).

DESIGN

Literature review.

METHODS

The authors conducted a review of literature available in the last 12 months in the English language using PubMed. The period used to conduct the literature search was from January 1, 2013, to December 31, 2013. The following search terms were used during the PubMed search: phacoemulsification, femtosecond laser, toric IOLs, multifocal IOLs, multifocal toric IOLs, manual small-incision cataract surgery, outcomes, surgically induced astigmatism, rotational stability, trifocal IOLs, laser cataract surgery, safety, and efficacy.

RESULTS

This review incorporates selected original articles that provide fresh insights and updates on the fields of toric and multifocal IOLs, femtosecond laser cataract surgery, and manual small-incision cataract surgery. Particular attention has been paid to observational, randomized controlled clinical trials, experimental trials, and analyses of larger cohorts with prospective and retrospective study designs. Letters to the editor, unpublished works, and abstracts do not fall under the purview of this review.

CONCLUSIONS

This review is not designed to be all-inclusive. It highlights and provides insights on literature that is most useful and applicable to practicing ophthalmologists.

Combined special capsular tension ring and toric IOL implantation for management of post-DALK high regular astigmatism with subluxated traumatic cataract

We report a case of 18-year-old male who has undergone phacoemulsification with implantation of toric IOL (AcrySof IQ SN6AT9) after fixation of lens capsule with Cionni's capsular tension ring (CTR) for subluxated traumatic cataract with high astigmatism after deep anterior lamellar keratoplasty (DALK). He underwent right eye DALK for advanced keratoconus four years earlier. He had history of trauma one year later with displaced clear crystalline lens into  anterior chamber and graft dehiscence, which was repaired successfully. The graft survived, but patient developed cataract with subluxated lens, for which phacoemulsification with implantation of toric IOL was done. Serial  topography showed regular corneal astigmatism of -5.50 diopter (K 1 42.75 D @130°, K 2 48.25 D @40°). At 10-month follow-up, the patient has BCVA 20/30 with + 0.75 DS/- 1.75 DC @ 110°. The capsular bag is quite stable with well-centered IOL. Combination of Cionni's ring with toric IOL could be a good option to manage such complex cases.

Visual performance of 2 aspheric toric intraocular lenses: comparative study

PURPOSE

To compare the visual and aberrometric outcomes of 2 aspheric toric intraocular lenses (IOLs).

SETTING

Fatebenefratelli e Oftalmico Hospital, Milan, Italy.

DESIGN

Prospective randomized comparative study.

METHODS

Astigmatic patients had cataract surgery with implantation of an Acrysof SN6AT IOL (Group A) or an AT Torbi 709M IOL (Group B). The uncorrected (UDVA) and corrected (CDVA) distance visual acuities, net refractive astigmatism, spherical equivalent (SE), IOL misalignment, and optical quality were evaluated 3 months postoperatively.

RESULTS

The study included 72 eyes. No statistically significant difference was found in UDVA, CDVA, residual refractive astigmatism, intraocular or total higher-order aberrations (Z(n,i) (order of aberrations calculated: 3≤n≤8), coma Z(3,±1), or trefoil Z(3,±2). The UDVA was 0.3 logMAR or better in all eyes and 0.1 logMAR or better in 55.5% of eyes in Group A and in 61.1% of eyes in Group B. Considering polar value analysis, 94.4% of eyes in both groups had a refractive astigmatism value within ±0.50 diopter at KP90 (polar value along 90-degree meridian). The SE was closer to emmetropia in Group A (P=.01). Intraocular lens misalignment of less than 5 degrees was present in 61.1% of cases in Group A (maximum 9 degrees) and in 66.6% in Group B (maximum 11 degrees). Spherical aberration Z(4,0) was significantly lower in Group B.

CONCLUSIONS

Both IOLs had similar clinical effectiveness in term of astigmatism correction, rotational stability, and optical quality. Eyes in Group A appeared significantly nearer to emmetropia, while the IOL in Group B induced significantly less spherical aberration.

FINANCIAL DISCLOSURE

No author has a financial or proprietary interest in any material or method mentioned.

Artisan aphakic lens for cataract surgery in anterior megalophthalmos

A 44-year-old man with anterior megalophthalmos arrived at the clinic presenting a cataract in the right eye. The corneal diameter was 13 mm. Iridodonesis and phacodonesis were evident during slit lamp examination. Anterior chamber depth was 5.89 mm, and the diameter of the capsular bag was approximately 14.45 mm. Due to the large capsular bag, a standard posterior chamber intraocular lens was considered inadequate because of potential instability. Phacoemulsification and an implantation of an iris-claw lens (Artisan for aphakia^®, Ophtec) in the posterior chamber were performed with good results. In the fourth postoperative month, uncorrected distance visual acuity was 20/30, and 20/20 was achieved with +0.75 −1.25 × 10°. We consider retropupillary aphakic iris-claw intraocular lenses to be a worthwhile option in these cases of megalophthalmos and cataract, since instability is avoided and the procedure is less challenging than suturing the lens.