Cataract surgery and intraocular lens implantation in anterior megalophthalmos

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.

How many challenges we may encounter in anterior megalophthalmos with white cataract: a case report

Background

Anterior megalophthalmos is a rare congenital disease which mainly features enlargement of the anterior segment. Cataract surgeries in anterior megalophthalmos can be challenging due to the anatomical anomalies while the studies upon the surgical design have been less integrated.

Case presentation

A 37-year-old woman presented with progressively blurred vision in the right eye after a transient fever 10 months ago. Her ocular history included hypermetropia with a spherical equivalent of + 4.00 OU. The review of systems showed bilateral varus deformity of distal interphalangeal joints on the little fingers. The patient denied family history of hereditary ocular diseases and her sister was born with uterus didelphys. On initial examinations, the corrected distance visual acuity was hand motion OD and 20/33 OS. Her intraocular pressure was 15 mmHg OD and 16 mmHg OS. Horizontal corneal diameter was 14 mm OD and 13.88 mm OS and axial length was 24.87 mm OD and 25 mm OS. Anterior segment photography showed bilateral iridal atrophy with deficiency in pupillary dilation and white cortically mature cataract in the right eye. Inspection by anterior segment optical coherence tomography indicated bilateral augmented anterior chambers with backward iridal concave on horizontal orientation. Ultrasound biomicroscopy showed partially peripheral anterior synechiae and pectinate ligaments at chamber angle in both eyes and opacified lens with the apparently elongated suspensory ligaments in the right eye. A deliberately selected 1-piece foldable intraocular lens (IOL) with frame haptics was implanted after phacoemulsification for good IOL stability. During the follow-up, the visual rehabilitation appeared relatively good and a lower degree of IOL dislocation comparing with existing reports was verified by OPD-Scan III aberrometry.

Conclusions

We presented the challenges and the original findings from a case of congenital anterior megalophthalmos with white cataract who underwent phacoemulsification and IOL implantation. This is the first report describing the comparison of the different IOL power calculation formulas in anterior megalophthalmos. Compared to the SRK/T and the Holladay II formulas, the Haigis formula could be a more accurate choice for the IOL calculation in anterior megalophthalmos according to our case. Moreover, the deliberate selection of IOLs is essential for IOL stability in these patients.

Rhegmatogenous retinal detachment with a giant tear located in the intermediate periphery: Two case reports

RATIONALE

We experienced 2 cases of retinal detachment (RD) with giant tears located in the intermediate periphery of the fundus. In this case report, we investigated the clinical characteristics in these 2 cases.

PATIENT CONCERNS AND DIAGNOSES

Case 1 involved a 63-year-old male, who became aware of metamorphopsia and decreased visual acuity (VA) in his left eye. Upon examination, he was diagnosed with a giant tear at the margin of the intermediate peripheral lattice degeneration. Case 2 involved a 54-year-old male, who became aware of decreased VA in his right eye. Upon examination, he was diagnosed with vitreous hemorrhage and a giant tear located in the upper intermediate periphery. In these 2 cases, there was no obvious previous or familial history.

INTERVENTIONS

In both cases, reattachment was achieved by performing vitrectomies.

OUTCOMES

These 2 cases were characterized by the refraction being close to emmetropia due to the flat corneal curvature, even though there was a long axial length and the eyeballs were spherically large. In both cases, the postoperative clinical course outcome was favorable and no complication occurred LESSONS:: Our findings indicate that intermediate peripheral giant tears may occur in spherically large eyeballs, and that vitreous surgery is effective in such cases. Since the risk of the onset of RD in the fellow eye is thought to be high, strict postoperative follow-up is necessary.

Trans-scleral explantation of posteriorly dislocated IOL-CTR complex in a case of anterior megalophthalmos with an unusually thin cornea

Anterior megalophthalmos and keratoglobus are characterised by corneal thinning and deep anterior chamber. They are clinically distinguished on the basis of normal to slightly decreased corneal thickness with a large corneal diameter (>13 mm) in case of anterior megalophthalmos, and marked limbus-to-limbus corneal thinning with globular protrusion in keratoglobus. To achieve and maintain a centred and stable intraocular lens (IOL) position in the bag is often difficult in cases of anterior megalophthalmos due to a too large diameter of the capsular bag and ciliary ring. We report a case of a 40-year-old man with features of anterior megalophthalmos with extremely thin cornea. He had spontaneous posterior dislocation of IOL and capsular tension ring (CTR) within the bag after initial successful cataract surgery. The dislocated complex could neither have been repositioned with scleral fixation due to large diameter of ciliary ring nor could it have been explanted through a clear corneal incision due to associated very thin cornea. We performed pars plana vitrectomy and separated the IOL-CTR complex inside the eye and explanted them separately through the sclerotomy, as is done for removal of intraocular foreign body. This avoided incision on the thin cornea. We conclude that this method can be very useful in a similar clinical situation but is complex enough to justify its use in routine cases.

Traumatic cataract in patient with anterior megalophthalmos: Case report

RATIONALE

Megalophthalmos anterior is a rare, bilateral, nonprogressive, hereditary, congenital disorder, characterized by the enlargement of all anterior segment structures of the eye, with megalocornea, iris atrophy, and zonular abnormalities commonly found. Usually almost asymptomatic in young patients, with most complaints concerning blurred vision due to the common corneal astigmatism, it might in time lead to several complications including premature cataract formation and pigmentary glaucoma.

PATIENT CONCERNS

This review presents the case of a 47-year old patient referred to our clinic for traumatic cataract surgery, with striking bilateral megalocornea, somehow overlooked during previous ophthalmic examinations in his local outpatient clinic.

DIAGNOSIS

We noticed markedly enlarged corneas and deepened anterior chambers of his both eyes, accompanied by intumescent, white cataract of the right eye, and incipient cortical cataract of the left eye. Best corrected visual acuity (BCVA) was counting fingers in the right eye and 20/25 in the left eye. Additional examination revealed multiple abnormalities of the anterior segment, leading to the diagnosis of anterior megalophthalmos. It is astounding the patient remained undiagnosed during previous examinations, with his megalocornea and remarkably deep anterior chamber so apparent.

INTERVENTIONS AND OUTCOMES

We performed standard phacoemulsification procedure, with 3 piece posterior chamber intraocular lens (PCIOL) implantation into the lens capsule. The surgery was uneventful, with postoperative BCVA of 20/20 in the right eye, and no dislocation of the lens in 9-month observation period.

LESSONS

Complicated cataract in patients with anterior megalophthalmos can be successfully treated with standard phacoemulsification procedure followed by the bag PCIOL implantation.Care needs to be taken during cataract surgery in these patients, as zonular abnormalities and lens enlargement are common, resulting in increased rate of intra- and postoperative complications. As patients with anterior megalophthalmos require a more careful follow-up.

Surgical Management of a Patient with Anterior Megalophthalmos, Lens Subluxation, and a High Risk of Retinal Detachment

The early development of lens opacities and lens subluxation are the most common causes of vision loss in patients with anterior megalophthalmos (AM). Cataract surgery in such patients is challenging, however, because of anatomical abnormalities. Intraocular lens dislocation is the most common postoperative complication. Patients with AM also seem to be affected by a type of vitreoretinopathy that predisposes them to retinal detachment. We here present the case of a 36-year-old man with bilateral AM misdiagnosed as simple megalocornea. He had a history of amaurosis in the right eye due to retinal detachment. He presented with vision loss in the left eye due to lens subluxation. Following the removal of the subluxated lens, it was deemed necessary to perform a vitrectomy in order to prevent retinal detachment. Seven months after surgery, an Artisan^® Aphakia iris-claw lens was implanted in the anterior chamber. Fifteen months of follow-up data are provided.

Pediatric cataract surgery in buphthalmos

PURPOSE

The pediatric eye offers many inherent surgical difficulties and when associated with a large buphthalmic eyeball, acts as a challenging ground for cataract surgeons. The purpose of our study is to describe the surgical outcome of cataract surgery in 6 children with buphthalmos.

METHODS

Eight eyes of 6 children with congenital glaucoma (buphthalmos) underwent phacoaspiration with or without intraocular lens (IOL) implantation. Demographic data, history of glaucoma surgery, intraocular pressure, biometry, surgical steps, and intraoperative and surgical outcome were noted for all patients from medical records. Postoperative outcome in terms of IOL stability, centration, visual acuity, and intraocular pressure were evaluated.

RESULTS

Pediatric cataract surgery was performed in 8 eyes with buphthalmos. Implantation of IOL was possible in 7/8 eyes. Primary posterior capsulorhexis (PPC) was done in 2/8 eyes. The IOL was implanted in the bag in 3 eyes and captured in 4 eyes. Decentration of IOL occurred in 100% of eyes where PPC was performed. Membranectomy for visual axis obscuration was done in 3 eyes.

CONCLUSIONS

Standard IOLs remain stable and centered with endocapsular implantation or rhexis fixation of IOL after pediatric cataract surgery in buphthalmos. However, PPC should not be attempted in the same sitting, as it leads to decentration.

Hereditary anterior megalophthalmos with posterior vitreoretinopathy: a surgical challenge

Anterior megalophthalmos is an inherited condition characterised by enlargement of the anterior segment with associated glaucoma and vitreoretinopathy. These associations make surgical management very challenging. A 12-year-old boy, diagnosed and operated elsewhere for congenital glaucoma in both eyes, presented with raised intraocular pressure. Investigations revealed enlarged corneal diameter, increased anterior chamber depth with thick, clear cornea and no Haab striae while fundus evaluation revealed posteriorly dislocated cataractous lens with total rhegmatogenous retinal detachment in both eyes. The surgical challenges in management are highlighted in this case where appropriate investigations can aid in the selection of appropriate surgeries with good visual outcome.

Successful visual rehabilitation in a case of anterior megalophthalmos

We report a case of 40-year-old female who presented with diminution of vision in both eyes. Ocular evaluation showed presence of bilateral megalocornea with deep anterior chamber, iridodonesis, cataract, and anterior embryotoxon. She was diagnosed with bilateral anterior megalophthalmos. She underwent an uneventful cataract extraction with standard posterior chamber intraocular lens implantation of overall large diameter in the left eye. Zonular dialysis was not evident intraoperatively despite the presence of iridodonesis. Postoperatively the intraocular lens was well centered throughout follow up. This case report reviews this rare disorder and highlights successful visual rehabilitation.

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.

Application of ultrasound biomicroscopy in the planning of cataract surgery in anterior megalophthalmos

Anterior megalophthalmos, a rare hereditary disorder, is macrocornea (horizontal corneal diameter more than 13 mm) in association with enlarged lens-iris diaphragm and ciliary ring. One of the major challenging issues in the cataract surgery of these patients is preventing intraocular lens (IOL) malposition, because of probable large capsular bag. Several approaches have been selected by previous surgeons, such as, custom-made anterior chamber IOLs. In this study, we show a normal capsular bag diameter despite ciliary ring enlargement, with application of ultrasound biomicroscopy (UMB). We suggest that in cases of anterior megalophthalmos without phacodonesis, UBM could measure the actual size of the capsular bag and obviate the need for further procedures.

Vitreoretinal Disorders in Anterior Megalophthalmos

PURPOSE

To describe vitreoretinal abnormalities in patients with anterior megalophthalmos (AM) and to report the results of vitreoretinal surgery in these cases.

METHODS

In a retrospective, noncomparative case series, a diagnosis of AM was made according to the following criteria: megalocornea, iris hypoplasia, lens subluxation, cataract formation at an early age, and absence of congenital glaucoma. Vitreous biomicroscopy and funduscopy were performed in all patients. Patient records were also reviewed.

RESULTS

Twenty-four patients with AM (12 male, 12 female), aged 4 months to 64 years, were included in this study. Funduscopy was possible in 46 eyes. Vitreous degeneration was the most common abnormal posterior segment finding, present in 34 eyes (73.9%). Nine eyes (19.5%) had optically empty vitreous with strands. Lattice degeneration was seen in five eyes (10.8%). Spontaneous vitreous hemorrhage occurred in three eyes, and peripheral retinal neovascularization was detected in two. Retinal detachment occurred in 18 eyes (37.5%); retinal breaks were detected in eight of these before surgery. Thirteen eyes underwent a total of 18 procedures. Retinal reattachment was finally achieved in 12 of the 13 eyes.

CONCLUSIONS

Anterior megalophthalmic eyes seem to be affected by a type of vitreoretinopathy predisposing to retinal detachment. Current vitreoretinal surgical techniques usually achieve good anatomic results in these cases.

Phacoemulsification in anterior megalophthalmos

This case outlines the phacoemulsification technique used to overcome the challenge of the hyperdeep anterior chamber, weak zonules, abnormal anterior capsule, and large capsular bag. Key steps included trypan blue staining of the anterior capsule, a large capsulorhexis, prolapse of the nucleus into the anterior chamber with phacoemulsification anterior to the capsulorhexis, and a posterior chamber-placed iris-clip intraocular lens. Successful visual rehabilitation is achievable in these anatomically challenging eyes.

Anterior megalophthalmos in a family with 3 female siblings

This report describes different modes of management in 3 sisters with anterior megalophthalmos. We report our management of the anterior megalophthalmos and a new technique of anterior chamber intraocular lens implantation, which was used in 1 case.