AN ON TABLE DIAGNOSIS OF BRITTLE CORNEA SYNDROME

Chief Author: Dr Ronak Solanki Co Authors: Dr Seema Ramakrishnan

Aravind Eye Hospital, PondicherryE-Poster 0050

INTRODUCTION• The Brittle Cornea Syndrome (BCS) is a generalized

connective tissue disorder characterized by corneal rupture following only minor trauma

• Associated keratoconus or keratoglobus, blue sclerae, hyperelasticity of the skin without excessive fragility, and hypermobility of the joints.

• It is inherited as an autosomal recessive trait and mutations in the Zinc-Finger-469 (ZNF469) gene are believed to be causative for BCS

• The BCS is sometimes confused with the kyphoscoliotic type of Ehlers–Danlos syndrome (EDS VI; MIM 225400)

CASE REPORT• A 36 Year male patient came to

us with the chief complains of – Pain and sudden onset Loss of

vision in the Right eye (RE) – after an alleged minor trauma with

finger nail of his brother’s 8 year old daughter previous night.

• Previous Significant history ( as per the old hospital records ) of– Total loss of vision in Left eye (LE)

in childhood and disfigurement ( Clinically Pthisis Bulbi ) due to trauma while playing

– documented Blue Sclera in RE on one of his previous visit for checkup.

CLINICAL FEATURES

• LE showed features of Phthisis bulbi.

• Visual acuity in RE was Perception of Light + , PR accurate

• Lid edema , Proptosis• Chemosis congestion • Full thickness linear corneal tear of 9.5 mm in

the inferior peripheral cornea almost from limbus to limbus extent ( keeping in mind the minor trauma with a finger nail )

• Associated Flat anterior chamber without any iris prolapse and obscured other details .

GENERAL EXAMINATION

• Slurry verbal responses to raise a suspicion of some form of mental retardation confirmed by family members.

• Born to parents with non Consanguineous marriage

• Apparent Dentinogenesis Imperfecta like features

• Short stubby nose • Hearing Loss and the

use of Hearing Aid

• Mild contractures of fingers (5th finger) clinodactyly

• Small joint hypermobility

OPERATIVE PROCEDURE

• A Corneal tear repair under local peribulbar anesthesia was undertaken• An additional side port entry was planned and made which spontaneously

extended into a larger linear tear than the expected size .

Subsequent cheese wiring of sutures and difficulty in sealing the wound under air and viscoselastics helped us make a diagnosis of Brittle Cornea Syndrome while operating on the patient in the RE.

• Repaired Corneal Tear

• Repaired Extended side port.

DISCUSSION• In cases of corneal rupture primary repair is required. • Surgical repair of spontaneous corneal ruptures in brittle cornea

syndrome is difficult. • Corneal sealing can be achieved by a combination of

– cheese wiring sutures with bandage contact lens– pressure patches for one week– systemic carboanhydrase inhibitors

• Alternatively repair of corneal perforations has been described using– tissue adhesives in dry operative field,– viscoelastic agents,– onlay epikeratoplasty,– and gas(c3f8)/air tamponade.

• Intraoperative optical coherence tomography can be of great value to examine these patients with reduced visibility of anterior segment structures

MANAGEMENT CHECKLIST• OPHTHALMIC

– Ensure ongoing ophthalmology follow-up – Education and lifestyle advice: patient, family, school and other careers – Protective polycarbonate spectacles– Serial corneal scanning

• AUDIOLOGICAL– Serial pure tone audiometry and tympanography

• MUSCULOSKELETAl– newborns and children under 2 years: screening for hip dysplasia.– Monitor for scoliosis – Joint protection advice

• OTHER CLINICAL MANAGEMENT– Consider echocardiography, low threshold for cardiac investigation

• FAMILY IMPLICATIONS– Molecular testing for confirmation of diagnosis – Assessment and genetic testing of other at-risk individuals in family – Consider above interventions for heterozygous mutation carriers

CONCLUSION

• PREVENTION IS ALWAYS BETTER THAN CURE !!

• BCS is a condition that is important to recognise, in order to permit appropriate management, including avoidance of misattribution of corneal damage to non-accidental injury, and to facilitate genetic counselling.

BIBLIOGRAPHY1. Davidson AE, Borasio E, Liskova P, Khan AO, Hassan H, Cheetham ME et

al. Brittle cornea syndrome ZNF469 mutation carrier phenotype and segregation analysis of rare ZNF469 variants in familial keratoconus. Invest Ophthalmol Vis Sci. 2015 Jan 6;56(1):578-86.

2. Avgitidou G, Siebelmann S, Bachmann B, Kohlhase J, Heindl LM, Cursiefen C. Brittle Cornea Syndrome:Case Report with Novel Mutation in the PRDM5 Gene and Review of the Literature. Case Rep Ophthalmol Med. 2015;2015:637084.

3. Hailah Al-Hussain, Steffen M. Zeisberger, Peter R. Huber, Cecilia Giunta and Beat Steinmann. Brittle Cornea Syndrome and Its Delineation From the Kyphoscoliotic Type of Ehlers–Danlos Syndrome (EDS VI): Report on 23 Patients and Review of the Literature. American Journal of Medical Genetics 124A:28–34 (2004).