A 56-years-old man with good medical health presented with bilateral blurring of vision over 10 years. Slitlamp examination revealed a bilateral cataracta membranacea mainly on the periphery, but involving his visual axes. Cataract extraction and intraocular lens implantation were performed on both eyes. Anterior capsules were not intact in both eyes preoperatively. Anterior vitrectomy was performed in the left eye in view of posterior capsule rupture intraoperatively. Intraocular lens were inserted in sulcus in the left eye and in the bag in the right eye. Postoperatively, his visual acuity improved in both eyes but only moderately. The indication, timing of surgery and the surgical techniques will be discussed.
A Patient with Bilateral Cataracta Membranacea
From the United Christian Hospital, Kwun Tong, Hong Kong, SAR.
The authors have no financial or proprietary interest in the materials presented herein.
Address correspondence to Jeffrey C.F. Pong.
Accepted: July 20, 2009
Posted Online: March 09, 2010
Cataracta membranacea was first reported by the German doctor von Ammon in 1833.1 Since then there were only scanty case reports and they belonged to the category of congenital cataract. It is characterized by the liquefaction and resorption of the degenerated lens fibers. Patients usually develop total or subtotal lens opacification at birth. Years lader, with the absorption of lens fibers, only the anterior and posterior capsules are left with the rudimentary lens fibres.2,3 Till now, there has been no consensus as to the incidence, pathogenesis, and management of such cataract. In this report, a Chinese patient with bilateral cataracta membranacea is presented. According to the literature, it is the first report of a bilateral cataract membranacea in an Asian patient.
This is a 56-years-old man who first presented in 2000 with gradual deterioration of vision for around 10 years. Medical and familial histories were both unremarkable. His presenting visual acuity (VA) was 0.1 in both eyes, and the intraocular pressure was normal. Ocular movements were normal and there were no nystagmus. Slitlamp examinations revealed cataract in both eyes with partial resorption of cortical matter at the center. The anterior lens capsules appeared thin in the center, but there was no lens material found in the anterior chamber. Both the anterior chambers were quiet with no signs of uveitis (Figs. 1 and 2). Ultrasound B-scan and fundal examinations were essentially normal.
Figure 1. Slitlamp Photo of RE Preoperatively (with Pupil Dilatation).
Figure 2. Slitlamp Photo of RE Postoperatively.
Both eyes were operated with a superior corneal approach. Intraoperatively, the anterior capsules were already partially ruptured in both eyes. Capsulor-rhexes were tried under viscoelastics but were only partially complete. Lens aspiration was performed with a Symcoe cannula and some of the cortical material was removed successfully. Viscoelastics were used to facilitate the residual cortex removal. The posterior capsule was ruptured during irrigation and aspiration in the left eye with vitreous prolapse, and anterior vitrectomy was performed. The intraocular lens was implanted in the sulcus in the left and the capsular bag in the right. Postoperatively, both eyes recovered well on topical G. Nadexin (dexamethasone and chloramphenicol). Despite a decrease in corneal endothelial counts post-operatively (600 cells/mm2 on LE and 1200 cells/mm2 on RE), both eyes demonstrated clear corneas, quiet anterior chambers, and good centration of intraocular lens, with an improvement of VA to 0.2 in both eyes at 6 months postoperatively.
Histologically, the anterior capsule was stained positive with PAS on the basement membrane with a monolayer of cuboidal epithelium on the surface. The lens material revealed degenerative changes with occasional globules within the lens material. Both specimens did not show other abnormalities.
Congential cataract embraces a variety of morphologies, and its pathogenesis is variable. Causes such as hereditary, metabolic diseases, maternal or intrauterine infections, trauma, and drugs have all been suggested. Intrauterine iridocyclitis has also been proposed as a cause of membranous cataract.3 Our patient has no family history of cataract and no known diseases during gestation and childhood. He denied previous trauma and other systemic diseases. Although his presenting VA was already poor, his premorbid VA was subjectively better, and there were no signs of nystagmus indicating poor VA in childhood. It is possible that the membranous cataract was only partial in childhood, but the lens resorption slowly progressed during the years of young adulthood, which has further deprived his VA subsequently. In this case, cataract extraction was attempted without capsular staining. However, we believe that the use of dyes such as vision blue can facilitate capsulorhexis and surgical outcome.
This case serves as a demonstration on the management of a bilateral cataracta membranacea, its indication and timing for surgery, and surgical techniques. It is important to be aware that albeit its rarity, cataracta membranacea can worsen in adulthood and necessitates surgery at a later stage.
- von Ammon. Die angeborene Cataracta in pathologischanatomischer, in pathogenetischer und in operativer Hinsicht. Ein Sendschreiben des Herausgebers an den Herrn Ober-Medicinalrath Dr Bauer in Kassel. Z Ophthal. 1833;3:70–99.
- Duke-Elder S. System of ophthalmology, vol III. In Part 2: Normal and abnormal development; congenital deformities. St Louis, MO: CV Mosby, 1964; 750–756.
- Heuring AH, Menkhaus S, et al. Cataract surgery in cataracta membranacea. J Cataract Refract Surg. 2002;28: 1065–1068. doi:10.1016/S0886-3350(01)01217-2 [CrossRef]