Congenital cataract- a riddle to be solved to prevent childhood blindness

Abstract

Introduction: Congenital cataract is a significant cause of visual disability in developing countries. It may present at birth or develop within first year of life. Common causes are genetic disorders, intra uterine infections, drug induced and others. Hence management protocol depends from case to case. Timely management of cataract and rehabilitation significantly prevents visual morbidity in children. Aims and Objectives: To asses visual outcomes in congenital cataract. Material and Methods: A prospective study was done from January 2017 to July 2018, including 40 patients with age ranging from 1 month to 12 years. Detailed history and thorough examination of each patient was done. After fulfilling inclusion criteria we have planned them for small incision cataract surgery (SICS) and phacoemulsification as per the financial status of family. Only cases less than 1 year were left aphakic. IOL power was calculated using SRK-II formula. Post operative visual acuity was noted on 7 day, 15 day and 1 month. Visual rehabilitation in the form of amblyopia therapy, secondary IOL and contact lenses was given. Result: It was found that squint (20%) and amblyopia (17.5%) was associated with cataract. All 40 eyes underwent cataract extraction by phacoemulsification (60%) and SICS (40%). Among them 25% cases were left aphakic. Visual improvement was almost similar in both surgeries. Visual rehabilitation in the form of spectacles (45%), contact lenses (5%), occlusion therapy (17.5%) and secondary IOL (22.5%) were given. Conclusion: Proper counseling of parents at diagnosis helps in prompt management and improves compliance which significantly reduces visual morbidity in children. Key wordsCongenital cataract, Visual outcome, Visual rehabilitation ................................................................................................................................................... Introduction Pediatric cataract is one of the major causes of preventable childhood blindness, affecting approximately 200,000 children worldwide, with an estimated prevalence ranging from three to six per 10,000 live births [1-3]. Pediatric cataracts may be congenital if present within the first year of life, developmental if present after infancy, or traumatic. Common causes are genetic disorders, intra uterine infections, drug induced and others. Early diagnosis and treatment are of crucial importance to prevent the development of irreversible stimulus deprivation amblyopia. The management of pediatric cataract should be customized depending upon the age of onset, laterality, morphology of the cataract, and other associated ocular and systemic co-morbidities. Manuscript received: 2 December 2018 Reviewed: 11 December 2018 Author Corrected: 16 December 2018 Accepted for Publication: 19 December 2018 Despite developments in surgical techniques and intraocular lenses, the management of unilateral pediatric cataracts is still clinically challenging. Better visual outcomes are usually obtained with early surgical correction and vigorous amblyopia treatment [4,5,6,7]. Visual system is developed in children as long as sharp, clear and focused images are formed on the retina of both eyes. Otherwise, amblyopia is observed. Therefore, early detection and surgery as well as follow-up visits have significant roles in the restoration of a child's vision in the case of congenital cataract with significant media opacity [8]. Unfortunately, in many cases, even after early surgery, long-term follow-up (at least up to the age of 10) is not properly instituted, and varying degrees of amblyopia have been reported despite wearing appropriate eye glasses, contact lenses, or implantation of intra ocular lenses (IOL) [9]. January – March 2019/ Vol 4/ Issue 1 Print ISSN : 2581-4907, Online ISSN : 2456-6454 Original Research Article Tropical Journal of Ophthalmology and Otolaryngology Available online at: www.medresearch.in 2|P a g e The first years of life are crucial for the development of a child’s vision and therefore irreversible amblyopia can be induced by blurred and distorted retinal image over that period [10,11]. Material and Methods Study DesignProspective interventional study Sample Size and DurationA prospective interventional study was done from January 2017 to July 2018, including 40 patients upto 12 years of age. There was a programme going on by government RBSK (Rashtriya Bal Swasthya Karyakram) to prevent childhood blindness, so we have taken 24 patients out of 40 from this programme. MethodologyThe following clinical variables were analysed: patient’s gender, age at diagnosis, presenting symptoms, laterality, morphology, aetiology, presence of other ocular and systemic abnormalities, family history of cataract, follow up time and treatment. In case of surgery, the following parameters were assessed: age at surgery, time from diagnosis to surgery, intra and postoperative complications and pre and postoperative visual acuity. Detailed history and thorough examination of each patient was done. Ocular Examination1. Visual acuity and best corrected visual acuity (by preferential looking behaviour in younger (upto 3 year) and Snellen’s chart in older children (above 3 year). 2. Slit lamp bio microscopy by 90D or 78D lens 3. Fundus Examinationby direct ophthalmoscopy and indirect ophthalmoscopy using 20D lens. 4. BScan ultrasonography – to evaluate posterior segment pathology 5. BiometryIOL power was calculated using SRK-II formula. Keratometry was done using bousch and lomb automated keratometer under general anaesthesia. Axial length of eye using A-scan 6. Examination under anaesthesia (if required)  Intra ocular pressure by Sciotz tonometry  Syringing for patency of lacrimal apparatus. All routine pre operative blood investigations were sent along with TORCH (Toxoplasma, rubella, cytomegalo virus, herpes virus) profile of mothers and children. Post operative ocular examination and visual acuity was noted on 7 day, 15 day and 1 month. Visual rehabilitation in the form of amblyopia therapy, secondary IOL and contact lenses was given accordingly. Inclusion Criteria  Patients aged less than 12 years.  Parents who are willing to follow up Exclusion Criteria Children with associated ocular condition like  Traumatic cataract  Retinopathy of prematurity  Microphthalmos  Persistent fetal vasculature  Children with other systemic diseases like Marfan syndrome, Lowe’s syndrome, Galactosemia, Hypothyroidism and those with learning disability were also excluded. After fulfilling inclusion criteria we have planned them for small incision cataract surgery (SICS) and phacoemulsification as per the financial status of family. Results Table-1: Demographic profile. S. No. Sex Number of patients % 1. Male 20 (50%) 2. Female 20 (50%) In our study equal sex distribution was observed. January – March 2019/ Vol 4/ Issue 1 Print ISSN : 2581-4907, Online ISSN : 2456-6454 Original Research Article Tropical Journal of Ophthalmology and Otolaryngology Available online at: www.medresearch.in 3|P a g e Table-2 Demographic profile. S. No Age group Number of patients % 1. <1 Year 10 25% 2. 1 -5 Years 10 25% 3. >5 Years 20 50% In our study 50% patients were age group more than 5 year. Table-3 Type of surgery Serial No. Procedure Number of patients % 1. SICS with PCIOL 12 30% 2. SICS + Anterior Vitrectomy 4 10% 3. Phacoemulsification with PCIOL 18 45% 4. Phacoemulsification + Anterior Vitrectomy 6 15% In our study 60% cases were of phacoemulsification (PCIOL/Anterior vitrectomy) Table-4: Pseudophakic/Aphakic. Procedure Number of patients % PCIOL Implanted 30 75% Aphakia 10 25% In our study PCIOL is implanted in most of the cases. Table-5: Laterality. Sex Children with Bilateral presentation Children with unilateral presentation Male 14(35%) 6(15%) Female 12(30%) 8(20%) Total 26 14 In our study bilateral presentation were more common. Table-6: Pre-operative visual acuity according to age group. Visual Acuity Age <1 Year % 1-5 Years % >5 Years % Uncooperative 6 15% 2 5% 0 0 FL TO CF 4 10% 4 10% 8 20% 1/60-6/60 0 0 3 7.5% 6 15% >6/60 0 0 1 2.5% 6 15% Total 10 10 20 Pre operative visual acuity were Following light to counting fingers in most of the cases. January – March 2019/ Vol 4/ Issue 1 Print ISSN : 2581-4907, Online ISSN : 2456-6454 Original Research Article Tropical Journal of Ophthalmology and Otolaryngology Available online at: www.medresearch.in 4|P a g e Table-7: Post operative best corrected visual acuity at 1 month Visual Acuity Age <1 Year % 1-5 Year % >5 Year % Uncooperative 2 5% 0 0 0 0 FL TO CF 8 20% 1 2.5% 2 5% 1/60-6/60 0 0 5 12.5% 8 20% >6/60 0 0 4 10% 10 25% Total 10 10 20 Post operative visual acuity was improved to more than 6/60 Table-8: Fundus evaluation in operated cases Fundus Appearance Number of patients Salt & pepper retinopathy 6 Myopic fundus 5 Normal 29 In our study, normal fundus were found in most of the cases Table-9: Type of cataract Type of Cataract Number of patients Lamellar cataract 5 Zonular cataract 7 Membranous cataract 28 We have found that 5 children came positive for TORCH infections. Among them one was positive for Rubella (Titre >1.1) and other 4 were positive for both Rubella as well as cytomegalovirus (Titre >1.1). Visual RehabilitationVisual rehabilitation was given in the form of spectacles, contact lenses, secondary IOL, occlusion therapy. Spectacles were the most commonly prescribed mode of visual rehabilitation followed by contact lenses January – March 2019/ Vol 4/ Issue 1 Print ISSN : 2581-4907, Online ISSN : 2456-6454 Original Research Article Tropical Journal of Ophthalmology and Otolaryngology Available online at: www.medresearch.in 5|P a g e Discussion In the present study, the clinical and surgical data of 40 patients with congenital cataract were taken. The youngest child in this study was 1 month old and eldest was 12 years old. Most of the cases in our study were operated at more than 5 year of age while