OPHTHALMOLOGY CLINICS for

Postgraduates

New Delhi | London | PanamaThe Health Sciences Publisher

Editors

Prafulla Kumar Maharana MD DNBAssistant Professor

Dr Rajendra Prasad Centre for Ophthalmic Sciences All India Institute of Medical Sciences (AIIMS)

New Delhi, India

Namrata Sharma MDProfessor

Dr Rajendra Prasad Centre for Ophthalmic Sciences All India Institute of Medical Sciences (AIIMS)

New Delhi, India

Atul Kumar MD FAMSProfessor and Chief

Dr Rajendra Prasad Centre for Ophthalmic SciencesAll India Institute of Medical Sciences (AIIMS)

New Delhi, India

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Ophthalmology Clinics for PostgraduatesFirst Edition: 2017ISBN: 978-93-86322-89-0

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Dedicated toMy parents, Mr Devendra Maharana and Mrs Binadini Maharana

—Prafulla Kumar Maharana

My parents, Dr Ramesh C Sharma and Mrs Maitreyi Pushpa My husband, Dr Subhash Chandra; and, Daughter, Vasavdatta

—Namrata Sharma

My late parents, Mr Sanat Kumar and Mrs Swarna Kumar My wife, Mrs Parul Kumar; and, Children, Aman and Arshi

—Atul Kumar

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Contributors

Atul Kumar MD FAMS Professor and Chief Dr Rajendra Prasad Centre for Ophthalmic Sciences All India Institute of Medical Sciences New Delhi, India

Adarsh Shashni MD Senior Resident Dr Rajendra Prasad Centre for Ophthalmic Sciences All India Institute of Medical Sciences New Delhi, India

Aditi Dubey MBBS MS (Ophthal) Assistant Professor Department of Ophthalmology Gandhi Medical College Bhopal, Madhya Pradesh, India

Amar Pujari MD Senior Resident Dr Rajendra Prasad Centre for Ophthalmic Sciences All India Institute of Medical Sciences New Delhi, India

Ashish Markan MBBS Junior Resident Dr Rajendra Prasad Centre for Ophthalmic Sciences All India Institute of Medical Sciences New Delhi, India

Ashutosh Kumar Gupta MS Graded Specialist, Ophthalmology Military Hospital Agra, Uttar Pradesh, India

Aswini Kumar Behera MD Junior Resident Dr Rajendra Prasad Centre for Ophthalmic Sciences All India Institute of Medical Sciences New Delhi, India

Bijnya Birajita Panda MS FICO (UK) Consultant Kar Vision Eye Hospital Bhubaneswar, Odisha, India

Brijesh Takkar MD FICO FAICO Senior Research Associate Dr Rajendra Prasad Centre for Ophthalmic Sciences All India Institute of Medical Sciences New Delhi, India

Deepali Singhal MD Senior Resident Dr Rajendra Prasad Centre for Ophthalmic Sciences All India Institute of Medical Sciences New Delhi, India

Devesh Kumawat MD DNB Senior Resident Dr Rajendra Prasad Centre for Ophthalmic Sciences All India Institute of Medical Sciences New Delhi, India

Devika S Joshi MS Fellow Narayana Nethralaya Bengaluru, Karnataka, India

Dewang Angmo MD DNB MNAMS FRCS Assistant Professor Dr Rajendra Prasad Centre for Ophthalmic Sciences All India Institute of Medical Sciences New Delhi, India

Dhaval Patel MD Consultant Centre for Sight Vadodara, Gujarat, India

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Ophthalmology Clinics for Postgraduatesviii

Dheepak Sundar MD Senior Resident Dr Rajendra Prasad Centre for Ophthalmic Sciences All India Institute of Medical Sciences New Delhi, India

Divya Agarwal MBBS Junior Resident Dr Rajendra Prasad Centre for Ophthalmic Sciences All India Institute of Medical Sciences New Delhi, India

D Satyasudha MBBS Junior Resident Dr Rajendra Prasad Centre for Ophthalmic Sciences All India Institute of Medical Sciences New Delhi, India

Esha Agarwal MD Senior Resident Dr Rajendra Prasad Centre for Ophthalmic Sciences All India Institute of Medical Sciences New Delhi, India

Harathy Selvan MBBS Junior Resident Dr Rajendra Prasad Centre for Ophthalmic Sciences All India Institute of Medical Sciences New Delhi, India

Harika Regani MBBS Junior Resident Dr Rajendra Prasad Centre for Ophthalmic Sciences All India Institute of Medical Sciences New Delhi, India

Jeewan S Titiyal MD Professor Dr Rajendra Prasad Centre for Ophthalmic Sciences All India Institute of Medical Sciences New Delhi, India

Jennil Shetty MBBS DNB Resident LV Prasad Eye Institute Bhubaneswar, Odisha, India

Jyotiranjan Mallick MS (Ophthal) Senior Resident Department of Ophthalmology All India Institute of Medical Sciences Bhubaneswar, Odisha, India

Karthikeya R MD DNB Senior Resident Dr Rajendra Prasad Centre for Ophthalmic Sciences All India Institute of Medical Sciences New Delhi, India

Mandeep S Bajaj MD Professor Dr Rajendra Prasad Centre for Ophthalmic Sciences All India Institute of Medical Sciences New Delhi, India

Manpreet Kaur MD Senior Resident Dr Rajendra Prasad Centre for Ophthalmic Sciences All India Institute of Medical Sciences New Delhi, India

Namrata Sharma MD Professor Dr Rajendra Prasad Centre for Ophthalmic Sciences All India Institute of Medical Sciences New Delhi, India

Neelima Aron MD DNB FICO Senior Resident Dr Rajendra Prasad Cenre for Ophthalmic Sciences All India Institute of Medical Sciences New Delhi, India

Patil Mukesh Prakash MBBS MD FICO Senior Resident Dr Rajendra Prasad Centre for Ophthalmic Sciences All India Institute of Medical Sciences New Delhi, India

Prafulla Kumar Maharana MD DNB Assistant Professor Dr Rajendra Prasad Centre for Ophthalmic Sciences All India Institute of Medical Sciences New Delhi, India

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Contributors ix

Prakhar Goyal MBBS DNB Consultant Goyal Eye Hospital Narnaul, Haryana, India

Pranayi Behera MS Senior Resident Department of Ophthalmology All India Institute of Medical Sciences Bhubaneswar, Odisha, India

Pranita Sahay MD Senior Resident Dr Rajendra Prasad Cenre for Ophthalmic Sciences All India Institute of Medical Sciences New Delhi, India

Prateek Kakkar MD DNB FICO FAICO Senior Resident Dr Rajendra Prasad Centre for Ophthalmic Sciences All India Institute of Medical Sciences New Delhi, India

Priyanka Ramesh MBBS Junior Resident Dr Rajendra Prasad Centre for Ophthalmic Sciences All India Institute of Medical Sciences New Delhi, India

Pulak Agrawal MD Senior Resident Dr Rajendra Prasad Centre for Ophthalmic Sciences All India Institute of Medical Sciences New Delhi, India

Raghav Ravani MD Senior Resident Dr Rajendra Prasad Centre for Ophthalmic Sciences All India Institute of Medical Sciences New Delhi, India

Rajesh Pattebahadur MD Senior Resident Department of Ophthalmology All India Institute of Medical Sciences Bhopal, Madhya Pradesh, India

Rajesh Sinha MD Professor Dr Rajendra Prasad Centre for Ophthalmic Sciences All India Institute of Medical Sciences New Delhi, India

Ritika Mukhija MBBS Junior Resident Dr Rajendra Prasad Centre for Ophthalmic Sciences All India Institute of Medical Sciences New Delhi, India

Ritu Nagpal MD Fellow Cornea LV Prasad Eye Institute Hyderabad, Telangana, India

Ruchita Falera MD DNB FICO Senior Resident Dr Rajendra Prasad Centre for Ophthalmic Sciences All India Institute of Medical Sciences New Delhi, India

Ruchir Tewari MD Senior Resident Dr Rajendra Prasad Centre for Ophthalmic Sciences All India Institute of Medical Sciences New Delhi, India

Sagnik Sen MBBS Junior Resident Dr Rajendra Prasad Centre for Ophthalmic Sciences All India Institute of Medical Sciences New Delhi, India

Sandeep Gupta MS DNB MNAMS Associate Professor Department of Ophthalmology Armed Forces Medical College Pune, Maharashtra, India

Sapna Raghuwanshi MS Assistant Professor Department of Ophthalmology LN Medical College Bhopal, Madhya Pradesh, India

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Saranya Devi K MD DNB FICO Senior Resident Dr Rajendra Prasad Centre for Ophthalmic Sciences All India Institute of Medical Sciences New Delhi, India

Shipra Singhi MD Consultant ASG Eye Hospital Jodhpur, Rajasthan, India

Shorya Vardhan Azad MS Assistant Professor Dr Rajendra Prasad Centre for Ophthalmic Sciences All India Institute of Medical Sciences New Delhi, India

Shreyas Temkar MD DNB FICO FAICO Senior Resident Dr Rajendra Prasad Centre for Ophthalmic Sciences All India Institute of Medical Sciences New Delhi, India

Swati Phuljhale MD Assistant Professor Dr Rajendra Prasad Centre for Ophthalmic Sciences All India Institute of Medical Sciences New Delhi, India

Talvir Sidhu MD DNB Senior Resident Dr Rajendra Prasad Centre for Ophthalmic Sciences All India Institute of Medical Sciences New Delhi, India

Tushar Agarwal MD Professor Dr Rajendra Prasad Centre for Ophthalmic Sciences All India Institute of Medical Sciences New Delhi, India

Vaishali Ghanshyam Rai MBBS DNB Senior Resident Department of Ophthalmology All India Institute of Medical Sciences Bhopal, Madhya Pradesh, India

Varsha Varshney MBBS MS Senior Resident Department of Ophthalmology All India Institute of Medical Sciences Jodhpur, Rajasthan, India

Yamini Attiku MBBS Junior Resident Dr Rajendra Prasad Centre for Ophthalmic Sciences All India Institute of Medical Sciences New Delhi, India

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Preface

“The whole art of medicine is in observation”.—Sir William Osler

Postgraduate exam is one of the most difficult and stressful milestones in the medical profession. It entails tremendous amount of stress on the candidates who appear for the exam. The never-ending knowledge of ophthalmology makes it quite difficult to revise all the cases from the standard textbooks before the exams. Further, the presentation of cases—long case or short case—is completely in a different format from what is given in the standard textbooks. Most of the time, the candidate fails to present the case properly in spite of good theoretical knowledge. The primary reason for this is that the format in which a topic is discussed in textbooks is completely different from that required for a practical exam.

This book attempts to present the important topics in a format that is exactly same as required in the practical exams. The primary focus is on history taking and proper clinical examination of the cases. Every effort has been made to describe the procedures of clinical examinations in such a way that the candidate can perform these examination techniques accurately in front of the examiner. Special emphasis has been given to the differential diagnosis of the cases, which is often a favorite question amongst the examiner. Clinical photographs of the cases as well as the important signs and investigation findings have been provided that will help the students for better understanding of the cases. The cases are being selected after discussing with experts in this field as well as candidates who have recently appeared in various postgraduate exams. Each chapter ends with a section on viva-voce questions that will help the candidates to mentally prepare for the viva before the final exam. In addition, a chapter on instruments has been included which is invariably a part of all postgraduate practical exams. The editors and all the contributors have made sincere efforts to make things simple and concise and to facilitate quick and thorough revision. However, it must be remembered that this is not a substitute to standard textbooks. The readers are encouraged to read standard textbooks before going through this book. This will make their under standing and application of this book more rewarding.

The editors wish best of luck to the students for their exams!

Prafulla Kumar MaharanaNamrata Sharma

Atul Kumar

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Contents

1. OCULOPLASTY 1

Long Cases•  Proptosis 1

Varsha Varshney, Amar Pujari, Mandeep S Bajaj

•  Lid Tumors 9Sapna Raghuwanshi, Amar Pujari, Mandeep S Bajaj

•  Ptosis 15Aditi Dubey, Amar Pujari

•  Contracted Socket 25Varsha Vashney, Aditi Dubey, Amar Pujari

•  Blow out Fracture of Orbit 30Aditi Dubey, Amar Pujari

•  Thyroid-associated Ophthalmopathy 35Aditi Dubey, Prafulla Kumar Maharana

•  Lacrimal Gland Tumors 44Varsha Vashney, Amar Pujari

Short Cases

•  Congenital Ptosis 52Aditi Dubey, Amar Pujari

•  Ectropion 56Aditi Dubey, Bijnya Birajita Panda

•  Entropion 60Aditi Dubey, Ritu Nagpal

•  Blepharophimosis, Ptosis, Epicanthus Inversus Syndrome 63Amar Pujari, Aditi Dubey

•  Sebaceous Gland Carcinoma 67Amar Pujari, Sapna Raghuwanshi

•  Pyogenic Granuloma 71Sapna Raghuwanshi, Bijnya Birajita Panda

•  Lagophthalmos 72Varsha Varshney, Ritu Nagpal

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•  Dermoid Cyst 77Shipra Singhi, Deepali Singhal

•  Orbital Hemangioma 82Aditi Dubey, Ritika Mukhija, Rajesh Pattebahadur

•  Coloboma of Eyelid 86Shipra Singhi, Amar Pujari

2. CORNEA AND CONJUNCTIVA 90

Long Cases•  Corneal Ulcer 90

Shipra Singhi, Tushar Agarwal, Prafulla Kumar Maharana, Namrata Sharma

•  Keratoconus 106Prafulla Kumar Maharana, Sapna Raghuwanshi, Manpreet Kaur, Namrata Sharma

•  Corneal Stromal Dystrophy 117Shipra Singhi, Divya Agarwal, Prafulla Kumar Maharana, Rajesh Sinha

•  Fuchs’ Endothelial Corneal Dystrophy 128Sapna Raghuwanshi, Ritu Nagpal, Prafulla Kumar Maharana, Namrata Sharma

•  Acute Graft Rejection 134Ritu Nagpal, Vaishali Ghanshyam Rai, Prafulla Kumar Maharana, Manpreet Kaur

Short Cases•  Keratoglobus 141

Prafulla Kumar Maharana, Sapna Raghuwanshi, Namrata Sharma

•  Pellucid Marginal Degeneration 144Sapna Raghuwanshi, Manpreet Kaur, Namrata Sharma

•  Band-shaped Keratopathy 148Manpreet Kaur, Sapna Raghuwanshi, Ritu Nagpal

•  Spheroidal Degeneration 150Sapna Raghuwanshi, Neelima Aron, Namrata Sharma

•  Congenital Hereditary Endothelial Dystrophy 153Prafulla Kumar Maharana, Vaishali Ghanshyam Rai, Manpreet Kaur

•  Iridocorneal Endothelial Syndrome 157Vaishali Ghanshyam Rai, Neelima Aron, Prafulla Kumar Maharana

•  Peters’ Anomaly 160Shipra Singhi, Neelima Aron, Manpreet Kaur

•  Limbal Dermoid 163Shipra Singhi, Deepali Singhal, Neelima Aron

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3. GLAUCOMA 171

Long Cases•  Primary Open Angle Glaucoma 171

Dewang Angmo, Vaishali Ghanshyam Rai, Ritika Mukhija

•  Primary Angle Closure Glaucoma 178Vaishali Ghanshyam Rai, Talvir Sidhu, Dewang Angmo

Short Cases

•  Sturge-Weber Syndrome 185Vaishali Ghanshyam Rai, Ritika Mukhija, Dewang Angmo

•  Buphthalmos 188Vaishali Ghanshyam Rai, Dewang Angmo

•  Neovascular Glaucoma 192Jennil Shetty, Talvir Sidhu

•  Angle-recession Glaucoma 197Prakhar Goyal, Divya Agarwal, Talvir Sidhu

•  Steroid-induced Glaucoma 200Vaishali Ghanshyam Rai, Talvir Sidhu

•  Pseudoexfoliation Glaucoma 203Vaishali Ghanshyam Rai, Dewang Angmo

4. RETINA 208

Long Cases•  Vitreous Hemorrhage  208

Shipra Singhi, Brijesh Takkar

•  Central Retinal Vein Occlusion 216Ashish Markan, Esha Agarwal, Brijesh Takkar

•  Branch Retinal Vein Occlusion 223Pulak Agrawal, Shorya Vardhan Azad

•  Proliferative Diabetic Retinopathy 229Brijesh Takkar, Dhaval Patel, Rajesh Pattebahadur

•  Nonproliferative Diabetic Retinopathy  236Dhaval Patel, Brijesh Takkar, Rajesh Pattebahadur

•  Retinitis Pigmentosa 244Jyotiranjan Mallick, Prafulla Kumar Maharana

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•  Macular Hole 252Vaishali Ghanshyam Rai, Brijesh Takkar

•  Retinal Detachment 260Pranayi Behera, Rajesh Pattebahadur, Raghav Ravani

•  Age-related Macular Degeneration 272Shipra Singhi, Raghav Ravani, Brijesh Takkar

•  Intermediate Uveitis 285Raghav Ravani, Karthikeya R, Harathy Selvan, Atul Kumar

•  Choroidal Melanoma 291Karthikeya R, Raghav Ravani, Prateek Kakkar, Atul Kumar

Short Cases

•  Cherry-red Spot 300Rajesh Pattebahadur, Brijesh Takkar

•  Central Serous Chorioretinopathy 303Vaishali Ghanshyam Rai, Raghav Ravani

•  Diabetic Macular Edema 308Brijesh Takkar, Dhaval Patel

•  Epiretinal Membrane 314Dhaval Patel, Brijesh Takkar

•  Fundal Coloboma 318D Satyasudha, Ruchir Tewari, Atul Kumar

•  Giant Retinal Tear 325Shipra Singhi, Brijesh Takkar

•  Posterior Segment Cysticercosis 329Harika Regani, Karthikeya R, Yamini Attiku, Atul Kumar

•  Cataract in Silicone Oil-filled Eyes 332Sagnik Sen, Esha Agarwal, Raghav Ravani, Atul Kumar

•  Silicone Oil-induced Secondary Glaucoma 337Ashish Markan, Esha Agarwal, Raghav Ravani, Atul Kumar

•  Posterior Dislocated Lens 341Shipra Singhi, Brijesh Takkar

•  Stargardt Disease 346Aswini Kumar Behera, Ruchir Tewari

•  Traumatic Retinal Detachment 350Priyanka Ramesh, Shreyas Temkar, Dheepak Sundar, Atul Kumar

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Contents xvii

5. NEURO-OPHTHALMOLOGY AND STRABISMUS 356

Long Cases•  Third Cranial Nerve Palsy 356

Adarsh Shashni, Shipra Singhi

•  Sixth Cranial Nerve Palsy 364Shipra Singhi, Swati Phuljhale

•  Fourth Cranial Nerve Palsy 371Swati Phuljhale, Shipra Singhi, Patil Mukesh Prakash

•  Optic Neuritis 377Ritu Nagpal, Adarsh Shashni

•  Esodeviation 384Shipra Singhi, Ritika Mukhija, Adarsh Shashni

•  Exodeviation 395Shipra Singhi, Adarsh Shashni

Short Cases•  Duane Retraction Syndrome 400

Shipra Singhi, Saranya Devi K

•  Ocular Myasthenia Gravis 403Shipra Singhi, Adarsh Shashni

6. LENS 409

Long Cases•  Zonular Cataract 409

Manpreet Kaur, Ashutosh Kumar Gupta, Jeewan S Titiyal

•  Ectopia Lentis 414Ruchita Falera, Manpreet Kaur, Prafulla Kumar Maharana

Short Cases

•  Lenticonus 421Manpreet Kaur, Prafulla Kumar Maharana, Jeewan S Titiyal

•  Posterior Polar Cataract 424Manpreet Kaur, Devika S Joshi, Jeewan S Titiyal, Sandeep Gupta

•  Microspherophakia 428Manpreet Kaur, Devika S Joshi, Prafulla Kumar Maharana

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•  Posterior Capsular Opacification 431Prafulla Kumar Maharana, Manpreet Kaur

•  Traumatic Cataract 435Deepali Singhal, Ruchita Falera, Manpreet Kaur

7. INSTRUMENTS 440

•  Ophthalmic Instruments 440Pranita Sahay, Devesh Kumawat

Index 463

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Lens

CHAPTER

6

LONG CASES

INTRODUCTION

Zonular cataract is the most common visually significant variant of pediatric cataract. It may be congenital or occur at a later stage of development, and is characterized by an opacity which occupies a discrete zone in the lens. It is usually bilateral, and has an autosomal dominant inheritance pattern.

It may be given as a long or short case in postgraduate/DNB/Diploma examination.

HISTORY

Chief Complaints

The informants are usually the parents who notice few or all of the following symptoms:zz Child does not recognize objects, toys or

parents (diminution of vision)zz White pupillary reflex (leukocoria)zz Involuntary continuous rhythmic movements

of the eye (nystagmus)zz Deviation of eye (Strabismus).

History of Present Illness

Etiology and genetics: It is usually hereditary with an autosomal dominant genetic pattern. This type of congenital cataract may be caused by mutations

in the heat-shock transcription factor-4 gene (HSF4) located at 16q21-q22.1.

An environmental form of zonular cataract may occur and is associated with vitamin D deficiency. Occasionally, maternal rubella infection contracted between 7th and 8th week of gestation may also cause zonular (lamellar) cataract.

Age at presentation: Patients with zonular cataract usually present in early childhood, though occasionally, they may present soon after birth.

Presenting features: Bilateral involvement is characteristic of zonular cataracts. Since the patients are often in the pre-school age group, a definitive history of diminution of vision may be difficult to elicit. The parents usually notice that the child is unable to see toys placed nearby, stumbles often and does not recognize faces of familiar persons. The parents may notice a white reflex or leukocoria. In cases where there is an asymmetric involvement of both eyes, strabismus may be the presenting complaint. Congenital cases may have associated involuntary ocular movements due to impaired development of fixation.

Antenatal and perinatal history: A history of fever associated with rash may be present in the mother in the antenatal period, which may point towards

ZONULAR CATARACTManpreet Kaur, Ashutosh Kumar Gupta, Jeewan S Titiyal

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Ophthalmology Clinics for Postgraduates410

rubella as the causative etiology. It is essential to rule out maternal malnutrition and history of drug or toxin intake in the antenatal period. Recurrent neonatal infections and malnutrition should be ruled out.

Family history: A positive family history of congenital or developmental cataract is present.

EXAMINATION

General Examination/Specific Systemic ExaminationZonular cataract is familial and usually not associated with any underlying systemic disorder.

However, a detailed examination is essential to rule out systemic disorders that are commonly associated with bilateral congenital cataracts, such as Toxoplasmosis, Other Agents, Rubella, Cytomegalovirus, and Herpes simplex (TORCH) syndrome, galactosemia and various mutational syndromes. The presence of microcephaly, d e a f n e s s, c a rd i a c a b n o r m a l i t i e s a n d developmental delay point towards an underlying systemic etiology and warrants a need for further investigations.

Ocular ExaminationVisual acuity: Visual acuity may be difficult to establish in very young children. Indirect evidence of diminution of vision include:zz Child does not follow objects or lightzz Inability to maintain central steady fixationzz Child resists occlusion of the good eyezz Strabismus (usually convergent squint)zz Nystagmus

Objective assessment of visual acuity may be made by the following tests:zz Infants: Preferential looking tests, Teller

acuity cards, Catford drum test, Optokinetic nystagmus and visual-evoked responses

zz 1–2 years: Worth’s ivory ball test, Sheridan’s ball test, Boek’s Candy test

zz 2–5 years: Dot acuity test, Miniature toy test, Sheridan-Gardiner test (HOTV) test, Tumbling E test, Allen picture cards, Beale-Collins picture chart tests, Kay picture test, Landolt C test, Snellen’s chart

Eyeball: Strabismus may be present, usually convergent squint. Nystagmus is present in cases with congenital onset of cataract

Eyelids, conjunctiva, cornea, sclera, iris, and pupil: Examination is usually unremarkable. Microcornea may be present in cases with underlying systemic syndrome.

Intraocular pressure is usually normal.

Lens: Typically, zonular cataract occurs in the zone of fetal nucleus surrounding the embryonic nucleus. The main mass of the lens internal and external to the zone of cataract is clear, except for small linear opacities like spokes of a wheel (riders), which may be seen towards the equator (Figs 1 and 2).

Vitreous and fundus: Examination is usually normal in bilateral zonular cataract. Salt and

Fig. 1: Zonular cataract with clear periphery and riders

Fig. 2: Zonular cataract retroillumination

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Lens 411

pepper retinopathy may be present in congenital rubella syndrome. Persistent hyperplastic primary vitreous may be associated, especially in unilateral cases.

DIFFERENTIAL DIAGNOSIS

zz Persistent hyperplastic primary vitreouszz Retinoblastomazz Endophthalmitiszz Retinal detachmentzz Toxocariasiszz Coat’s diseasezz Retinopathy of prematurityzz Astrocytic hamartomazz Vitreous hemorrhage.

INVESTIGATIONS

Systemic InvestigationsZonular cataract with positive family history and established hereditary basis for the cataract does not warrant any further investigation.

In other cases with bilateral cataract, the investigations should include the following:zz Serology for intrauterine infections: TORCH

titres (TORCH = toxoplasmosis, rubella, cytomegalovirus, herpes simplex virus, other viruses such as varicella), VDRL titres for syphilis.

zz Urine examination: Urinalysis for the presence of reducing sugars (galactosemia); urine chromatography for amino acids (Lowe’s syndrome).

zz Serum electrolytes (serum calcium and phosphorus)

zz Fasting blood glucosezz Serum galactokinase zz Thyroid function testszz Referral to a pediatrician may be warranted

for dysmorphic features or suspicion of other systemic diseases. Genetic testing and chromosome analysis may be useful in this context.

Ocular Investigations

zz Visual evoked responses (VER): To assess visual acuity and estimate visual potential

zz Biometry: Axial length and keratometry measurements for IOL power calculation

zz A-scan ultrasonography to give an estimate of axial length in infants and children uncooperative for biometry

zz B-scan ultrasonography: To rule out any posterior segment pathology.

MANAGEMENT

Conservative ManagementPartial cataracts, cataracts with less than 3 mm diameter and pericentral cataracts may not immediately require surgery and can be observed. Pupillary dilatation with 2.5% phenylephrine and part time occlusion of good eye may be tried in unilateral partial cataracts.

Surgical Management

Indications for Treatmentzz Cataract >3 mm diameterzz Dense nuclear cataract obstructing view of

funduszz Associated strabismus/nystagmuszz VA < 20/80.

Time of Surgical Interventionzz Bilateral dense cataracts require early

surgery within 6–8 weeks of age to prevent the development of stimulus deprivation amblyopia. In asymmetrical cataract, the eye with the denser cataract should be addressed first.

zz Unilateral dense cataract should be operated as soon as possible, ideally before 4–6 weeks of age. Results are often poor due to dense amblyopia and non-compliance with occlusion therapy.

zz Bilateral partial cataracts may not require surgery until later, if at all. In case of doubt, it may be prudent to defer surgery. Monitor lens opacities and visual function and intervene later, if vision deteriorates.

zz Partial unilateral cataract can usually be observed or treated non-surgically with mydriasis, and possibly part-time contralateral occlusion to prevent amblyopia.

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Biometry and IOL Power CalculationAccurate measurements of axial length and keratometry may be difficult in the preoperative period because of poor patient cooperation and poor fixation. Usually, examination under anesthesia has to be performed to determine axial length and keratometry. Immersion biometry is more predictable than the contact method for IOL-power calculation.

An under-correction of the IOL power is usually recommended in cases of pediatric cataract to account for the myopic shift following IOL implantation. Dahan et al. suggest an under-correction of 10% in children between 2 to 8 years and under-correction of 20% in children less than 2 years of age. They also suggested IOL power selection based on axial length alone (Table 1).

In cases with unilateral cataract, emmetropia may be aimed for to minimize the risk of amblyopia. Piggyback IOL or IOL exchange may be needed at a later date in such cases.

Surgical ProcedureThe primary surgical management consists of lens aspiration or lensectomy. Coaxial or bimanual lens aspiration via limbal route is preferred. Pars plana lensectomy may be undertaken in cases where IOL implantation is not planned.

Anterior capsulorhexis may pose a challenge due to the elastic pediatric anterior capsule, which has a propensity to extend. Cohesive OVD such as Healon GV facilitates anterior capsulorhexis as it maintains anterior chamber stability and offsets the vitreous upthrust.

Posterior continuous curvilinear capsulorhexis (PCCC) with limited anterior vitrectomy is recommended for children less than 7 years of age

to minimize the risk of visual axis opacification (VAO) and subsequent additional surgical procedures. In children older than 7 years, lens aspiration with IOL implantation is performed.

Primary IOL implantation is preferred in all unilateral cataract cases as well as bilateral cases when possible. In-the-bag implantation of single-piece hydrophobic IOL is preferred. Multipiece IOL in the sulcus may be implanted when in-the-bag IOL implantation is not possible.

Wound closure by stromal hydration alone may be inadequate because of low scleral rigidity, and sutures are often required to effectively seal the corneal incisions.

Postoperative Visual Rehabilitation Postoperative occlusion therapy and visual rehabilitation is essential to achieve optimal outcomes, as postoperative amblyopia may limit the visual potential in even a well-done cataract surgery. Optical correction in an aphakic child depends upon the patient age and laterality of aphakia.zz Aphakic glasses are effective for visual

rehabilitation in older children with bilateral aphakia. However, they result in unacceptable anisometropia and aniseikonia in unilateral aphakia. Aphakic glasses are heavy, cosmetically unattractive and result in spherical as well as prismatic aberrations.

zz Contact lenses provide a superior optical solution for both unilateral and bilateral aphakia. Tolerance is usually reasonable until the age of about 2 years; problems with compliance may start after this period as the child becomes more active and independent. Contact lens may become dislodged or lost, leading to periods of visual deprivation with the risk of amblyopia. Maintenance of hygiene may be problematic in young children, leading to a risk of microbial keratitis. The maintenance issues and financial cost limits the widespread usage of contact lenses.

zz IOL implantation is increasingly being performed in young children and even infants, and appears to be effective and safe in selected cases. Awareness of the rate of myopic shift, which occurs in the developing eye, combined with accurate biometry, allows the

Table 1 IOL power based on axial length (Dahan’s formula)

Axial length (mm) IOL power (D)

17 mm 28 D

18 mm 27 D

19 mm 26 D

20 mm 24 D

21 mm 22 D

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calculation of an IOL power targeted at initial hypermetropia (correctable with spectacles), which will ideally regress towards emmetropia later in life. However, final refraction is variable and emmetropia in adulthood cannot be guaranteed.

zz Occlusion therapy to prevent and treat amblyopia is vital in order to achieve optimal outcomes, especially in cases that have undergone unilateral cataract surgery. Atropine penalization may also be considered.

Complications

zz Visual axis opacification (VAO) is nearly universal, if the posterior capsule is retained in a child under the age of 6 years. An intact anterior hyaloid phase provides a scaffold for proliferation of lens epithelial cells and may result in VAO despite posterior capsulorhexis. The incidence of opacification is reduced when posterior capsulorhexis is combined with vitrectomy. Surgical membranectomy via limbal or pars plana route is required for management. Nd: YAG capsulotomy may be tried in cooperative children.

zz Secondary membranes may form across the pupil, particularly in microphthalmic eyes or those with associated chronic uveitis. A fibrinous postoperative uveitis in an otherwise normal eye, unless vigorously treated, may also result in membrane formation. Thin membranes can be treated with laser capsulotomy, thick membranes may require surgical excision.

zz Secondary glaucoma may develop in 3–32% of eyes undergoing pediatric cataract surgery. Pupillary block glaucoma may occur in the immediate postoperative period, especially in microphthalmic eyes. Secondary open-angle glaucoma may also develop years after the initial surgery. It is therefore important to monitor the intraocular pressure regularly for many years.

zz Retinal detachment is an uncommon and late complication after cataract surgery. The incidence of retinal detachment following cataract surgery has been reported between 1% and 1.5%.

VIVA QUESTIONS

Q.1. What is the etiology of congenital cataracts?

Ans. Etiology of bilateral cataracts: • Idiopathic • Familial(hereditary);usuallyautosomal

dominant • Chromosomalabnormality—Trisomy-21

( D ow n ) , T r i s o my - 1 8 ( Ed wa rd ) , Trisomy-13 (Patau). Other translocations, deletions, and duplications

• Craniofacial syndromes: Hallermann-Streiff, Rubinstein-Taybi, Smith- Lemli-Opitz.

• Musculoskeletal—Conradi, Albright,myotonic dystrophy

• Renal—Lowe,Alport • Metabolic—Galactosemia, Fabry,

Wilson, mannosidosis, diabetes mellitus • Maternalinfection(TORCHdiseases)—

Rubella, cytomegalovirus, varicella, syphilis, toxoplasmosis

• Ocular anomalies—Aniridia, Anteriorsegment dysgenesis syndrome

• Iatrogenic—Corticosteroids, Radiation(may also be unilateral)

Etiology of unilateral cataracts: • Idiopathic • Ocular anomalies—Persistent fetal

vasculature (PFV), anterior segment dysgenesis, retinal detachment

• Traumatic(ruleoutchildabuse)

Q.2. What are the contraindications for IOL implantation in pediatric cataract?

Ans. Contraindications of IOL implantation are: • Microphthalmos • Rubellacataract • Aniridia • Uveitis

Q.3. What are the surgical challenges faced in pediatric cataracts?

Ans. The intraoperative challenges faced in pediatric cataracts are:

• Difficultyincapsulorhexisformation • Positiveintravitrealpressure • Intraoperativemiosis • Woundleak

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Q.4. What are characteristic morphological variants of pediatric cataracts associated with systemic diseases?

Ans. Refer Table 2.

Q.5. Explain IOL power calculations in pediatric patients.

Ans. Refer text.

BIBLIOGRAPHY 1. Bradford GM, Keech RV, Scott WE. Factors

affecting visual outcome after surgery for bilateral congenital cataracts. Am J Ophthalmol. 1994;117:58-64.

2. Kugelberg M, Zetterström C. Pediatric cataract surgery with or without anterior vitrectomy. J Cataract Refract Surg. 2002;28(10):1770-3.

3. Lambert SR, Drack AV. Infantile cataracts. Surv Ophthalmol. 1996;40:427-58.

4. Medsinge A, Nischal KK. Pediatric cataract: challenges and future directions. Clinical Ophthalmology (Auckland, NZ). 2015;9:77-90.

5. Ram J, Brar GS, Kaushik S, Gupta A. Role of posterior capsulotomy with vitrectomy and intraocular lens design and material in reducing posterior capsule opacification after pediatric cataract surgery. J Cataract Refract Surg. 2003;29:1579-84.

ECTOPIA LENTISRuchita Falera, Manpreet Kaur, Prafulla Kumar Maharana

INTRODUCTION

Ectopia Lentis (subluxation of lens) is characterized by partial displacement of the lens from the patellar fossa. The first case of lens dislocation was reported by Berryat in 1749 and the term Ectopia Lentis was coined by Stellwag in 1856.1 The terms ectopia lentis and subluxated lens have been used interchangeably in literature, it is however, preferable to use ectopia lentis in cases of subluxation secondary to inheritable causes. Lens subluxation may be heritable without associated systemic syndrome, heritable with associated systemic syndrome, in association with ocular comorbidities or because of trauma (Table 1).

The most common cause of lens subluxation is trauma, which accounts for nearly 50% of all cases.

Table 2 Morphological variants of pediatric cataract associated with systemic diseases

Systemic disease Cataract morphology Associated findings

Fabry syndrome Spoke-like Corneal whorls

Mannosidosis Spoke-like Hepatosplenomegaly

Diabetes Vacuoles ↑ Blood glucose level

Hypoparathyroidism Multicolor flecks ↓serum calcium

Myotonic dystrophy Multicolor flecks Characteristic facial features, tonic “grip”

Wilson disease Green “sunflower” Kayser-Fleischer corneal ring

Lowe syndrome Thin disciform Hypotonia, glaucoma

Marfan’s syndrome is the most common heritable cause of ectopia lentis. Disruption or dysfunction of the zonular fibers of the lens is the underlying pathophysiology of ectopia lentis, regardless of cause (trauma or heritable condition). The degree of zonular impairment determines the degree of lens displacement.

It is given as a long or short case in post-graduate/DNB/Diploma examination.

HISTORY

EpidemiologyEctopia lentis can occur at any age. It may be present at birth, or it may manifest late in life. A male preponderance is reported, as males appear more prone to ocular trauma than

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females. Isolated ectopia lentis and Marfan’s syndrome have an autosomal dominant mode of inheritance.

Chief complaints: The patients may present with the following symptoms:zz Decreased or fluctuating visionzz Photophobiazz Glarezz Monocular diplopia zz Suboptimal correction with spectacles

History of present illness: Heritable ectopia lentis is bilateral, symmetric and stable from early childhood. Time of onset of disease, its progression and its effect on visual function should be noted. There is frequent change in glasses with a progressive increase in the power of glasses. Subluxation of lens associated with trauma can present with sudden diminution of vision or other symptoms like photophobia and monocular diplopia.

Past medical history: Ectopia lentis may be associated with underlying systemic disorders and a careful history must be elicited regarding the following:zz Any history of previous cardiac illness must

be taken. Cardiovascular manifestations

of Marfan’s syndrome include aortic and pulmonary artery dilatation, mitral and tricuspid valve prolapse with or without regurgitation. Dilatation of the sinus of Valsalva is found in 60–80% of adult and mitral valve prolapse (MVP) is present in 80% patients.1,2

zz Homocystinuria is a recessively inherited disorder caused by deficiency of cystathionine synthase leading to accumulation of homocysteine and methionine. Affected persons have tall, thin habitus similar to Marfan’s syndrome patients but infrequent arachnodactyly. Any history of developmental delay or mental retardation should be elicited as homocystinuria is associated with subnormal intelligence.

zz History of recurrent fractures, hip dislocation or any musculoskeletal abnormalities should be asked to rule out presence of any connective tissue diseases such as Ehlers- Danlos syndrome.

Family HistoryA three generation pedigree chart must be prepared. History of similar complaints in siblings and parents should be specifically asked.

EXAMINATION

Systemic ExaminationA careful systemic examination must be carried out and the findings suggestive of underlying systemic disorders must be noted.

Marfan’s syndrome may present with the following systemic signs:zz Long thin limbszz Arachnodactyly-long spider like fingerszz Arm span: Height ratio > 1.05zz Upper segment of body (Head to pubic bone):

Lower segment ratio <0.86zz Scoliosiszz Chest wall deformities (Pectus excavatum/

Pectus carinatum)zz Thumb sign (The thumb sign is positive when

the entire distal phalanx of the adducted thumb extends beyond the ulnar border of the palm)

zz Wrist sign (The wrist sign is positive when the tip of the thumb covers the entire fingernail

Table 1 Etiology of subluxated lens

•  Traumatic subluxation of lens•  Hereditary causes without systemic associations

– Isolated ectopia lentis– Ectopia lentis et pupillae

•  Hereditary causes with systemic associations– Marfan’s syndrome– Homocystinuria– Weill-Marchesani Syndrome– Hyperlysinemia– Sulfite oxide deficiency– Ehlers-Danlos syndrome– Crouzon’s syndrome– Oxycephaly

•  Associated with other ocular diseases– Mature or hypermature cataract– Buphthalmos– High myopia– Megalocornea– Pseudoexfoliation– Retinitis pigmentosa– Eales disease– Retinal detachment

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of the fifth finger when wrapped around the contralateral wrist.)

zz High-arched palateMusculoskeletal anomalies are also present in

homocystinuria, Weill-Marchesani syndrome and connective tissue disorders.

Cardiovascular examination should be performed to rule out underlying valvular heart defects in Marfan’s syndrome

Homocystinuria may have associated mental retardation and may necessitate IQ testing and evaluation of higher mental functions.

Ocular Examination

Visual acuity: Visual acuity should be carefully assessed considering the following points:zz Uncorrected visual acuity and BCVA must be

assessed in all caseszz Near vision should be documentedzz Refraction should be carried out through

phakic and aphakic zones (Fig. 1).

Eyeballs: Strabismus may be associated with Marfan’s syndrome, and if uncorrected in children can result into amblyopia. It may be a presenting sign of the disorder. Delayed and inadequate correction of refractive errors as well as deficient fibrillin in extraocular muscle pulleys causing their instability may explain the high incidence of strabismus in Marfan’s patients.

Conjunctiva is usually normal.

Cornea: Patients with Marfan’s syndrome can present with flat cornea (cornea plana) or steep cornea. Associated keratoconus may be present.

Sclera: Thinning of sclera may be present, giving it a bluish hue in Marfan’s Disease as well as in cases of connective tissue disorders such as osteogenesis Imperfecta and Ehler-Danlos syndrome.

Anterior chamber and angle:zz Ectopia lentis is usually associated with a deep

anterior chamber, however, it may be irregularzz Gonioscopy must be done in all cases to

rule out angle recession (in post-traumatic subluxation of lens)

Pupil:zz The pupil may be eccentrically placed as in

cases of ectopia lentis et pupillae where the pupil is displaced opposite to the direction of subluxation.

zz The pupil may be poorly dilating on account of hypoplastic dilator muscles

zz Relation of the lens with respect to the undilated pupil should be noted.

Lens:zz Any evidence of phacodonesis should be

documentedzz Evidence of cataract, if any should be

documentedzz Extent of subluxation should be noted in clock

hours.zz Direction of subluxation (Fig. 2) must be

noted.zz Zonules: Condition of the zonules should be

documented as they may be stretched in cases of Marfan’s disease (Fig. 3) or broken in case of homocystinuriaThe subluxation of the lens is generally

superotemporal in cases of Marfan’s syndrome.

Fig. 2: Superotemporal displacementFig. 1: Phakic and aphakic zones in ectopia lentis

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Fundus examination:zz Distant direct ophthalmoscopy examination:

A crescent-shaped reflex seen on distant direct ophthalmoscope is pathognomic of subluxated lens.

zz Detailed fundus examination is mandatory in all cases. Retinal detachment may occur in 5–11% of patients with Marfan’s syndrome, and its incidence increases to 8–38% in the presence of ectopia lentis.1 Unstable subluxated or dislocated lens capsule exerts traction on the vitreous base, leading to small tears or holes in the retinal periphery. Axial myopia presents in Marfan’s syndrome predisposes to early vitreous liquefaction and posterior vitreous detachment, retinal thinning, lattice degeneration, and peripheral breaks.

DIFFERENTIAL DIAGNOSIS

Ectopia lentis is diagnosed clinically on the basis of slit-lamp examination. Various etiologies responsible for ectopia lentis are tabulated in Table 1. Marfan’s syndrome and homocystinuria are common heritable systemic disorders associated with ectopia lentis and their differentiating features are summarized in Table 2.

INVESTIGATIONS

Systemic InvestigationsA case of ectopia lentis must be managed with a multidisciplinary approach along with a pediatrician, cardiologist and orthopedician.

Table 2 Differentiating features of Marfan’s disease and homocystinuria

Clinical features Marfan’s disease Homocystinuria

Etiology Fibrillin-1 (FBN1) gene mutation on chromosome 15

Deficiency of cystathionine synthase leading to accumulation of homocysteine and methionine

Mode of inheritance Autosomal dominant Autosomal recessive

Mental retardation Absent Present

Direction of subluxation Superotemporal subluxation of lens

Inferonasal subluxation of lens

Condition of zonules Primarily present with stretched zonules

Absent and broken zonules

Fig. 3: Stretched zonules in cases of Marfan’s disease

Preferential focusing of ultraviolet B light on the inferonasal quadrant of the crystalline lens is hypothesized to explain the predominantly supero-temporal dislocation (Fig. 2) of the lens in Marfan syndrome, while it is inferonasal in cases of homocystinuria. However, the direction of subluxation is not pathognomic, and it may occur in any direction. Premature cataracts and other lens and capsule opacities are commonly found in Marfan’s syndrome with presentation at a younger age (30–50s) compared to the general population.

In some cases, the patients may be aphakic with posterior dislocation of the lens into the vitreous cavity.

Intraocular pressure: Intraocular pressure should be documented in all cases. Primary open-angle glaucoma is most common, but glaucoma can be secondary to anterior lens dislocation or anterior chamber angle abnormalities.

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It should be evaluated for underlying systemic abnormalities.zz X-ray Chest/ECG/2D Echo should be done in

all cases to rule out cardiac abnormalities in Marfan’s syndrome.

zz Sodium nitroprusside test (in urine) must be done to rule out homocystinuria.

zz X-ray of spine and extremities are undertaken to evaluate the skeletal deformities

Ocular Investigationszz Biometry should be done to calculate IOL

powerzz B-scan ultrasonography: In cases of mature

cataract where the fundal view is obscured, a USG must be done to rule out retinal detachment or any posterior segment pathology.

MANAGEMENT

Conservative Managementzz A complete refraction considering the

undilated central pupillary position, size of the phakic and aphakic zones and preferred visual axis needs to be done.

zz Appropriate spectacle correction, aphakic glasses or contact lens can be given.

zz Other methods such as miotics to minimize diplopia or mydriatics to enlarge the aphakic zone are rarely used these days.

Surgical Management

Indications for Surgeryzz Subluxated lens bisects the pupil leading to

a phakic and aphakic zone in an undilated pupillary axis

zz Cataractous lenszz Associated complications like glaucoma or

pupillary blockzz Presence of lenticular astigmatismzz Anteriorly or posteriorly dislocated lens

Surgical management of subluxated lens depends on the degree of subluxation. The following are the modalities of management are mainly for secondary causes of lens subluxation.zz Subluxation < 3 clock hours: In cases of lens

subluxation of less than 3 clock hours, slow

motion phacoemulsification with PCIOL implantation in the bag can be attempted. Slow motion phacoemulsification includes phacoemulsification at low flow rate, low vacuum and low infusion bottle height in order to minimize stress on the zonules

zz Subluxation of 3–5 clock hours: In case of lens subluxation of 3–5 clock hours, slow motion phacoemulsification can be done. Insertion of capsular tension ring (CTR) or capsule tension segments (CTS) may be needed to support the bag. With the use of CTR, any force that is transmitted to the capsule does not directly impact the adjacent zonules, but is rather distributed to the entire zonular apparatus.

zz Subluxation of 5–7 clock hours: Slow motion phacoemulsification with the use of Cionni ring with PCIOL implantation can be attempted in cases of severe or progressive zonular weakness. Cionni ring has a hook, which needs to be kept opposite to the direction of decentration. A transcleral suture applied to it allows it to be pulled peripherally thereby counteracting the capsular bag decentration.

zz Subluxation of > 7 clock hours: Intracapsular cataract extraction (ICCE) with sclera fixated IOL or ACIOL implantation can be done in cases with extensively subluxated cataractous lens.

zz In cases with significant posterior subluxation of lens, pars plana lensectomy (PPL) with pars plana vitrectomy (PPV) can be done, followed by IOL implantation in the anterior chamber or sulcus-fixated IOL.The use of capsular support devices is not

preferred in cases of progressive zonular weakness. These are of particular importance in secondary causes of subluxation such as post-traumatic subluxation of lens and pseudoexfoliation where the basic zonular anatomy is not compromised.

In heritable ectopia lentis with or without underlying systemic disorders, intralenticular lens aspiration (Figs 4A to D) is the preferred technique, which is described as follows:zz In this technique, two openings are made

in the lens capsule with a microvitreoretinal (MVR) blade and the lens matter is aspirated using a bimanual irrigation and aspiration system.

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zz The capsular bag is then cut and aspirated using a vitrectomy probe.

This technique has several advantages such as:zz The lens can be stabilized with the irrigation

cannula, the area to be aspirated can be brought into focus, and a complete lens aspiration can be easily performed.

zz Additionally, the irrigation cannula hydrates the cortical matter, enabling complete aspiration.

zz Furthermore, creating two small capsular openings in the midperiphery of the lens that are directly visible often eliminates the problem of poor visibility.

zz There is less chance of vitreous becoming hydrated and lens matter falling into the vitreous cavity, as aspiration is intralenticular.

zz Another added advantage is that the capsular rim is left intact. This may allow IOL implantation in the sulcus once the capsular

Figs 4A to D: Intralenticular lens aspiration

rim fibroses, thus avoiding the complications and difficulties associated with anterior chamber and sulcus-fixated IOLs.

VIVA QUESTIONS

Q.1. What is the etiopathogenesis of Marfan’s disease?

Ans. Marfan’s syndrome is an autosomal dominant disorder with near complete penetrance and variable expression. There is a mutation in the Fibrillin locus (FBN1), which lies on the long arm of chromosome 15 (15q21). This results in abnormal biosynthesis of fibrillin, a 350 kd cysteine rich glycoprotein which is a major constituent of microfibrils present in connective tissue of suspensory ligaments of crystalline lens.

A

C

B

D

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Q.2. What are the differences between Homocystinuria and Marfan’s disease?

Ans. Refer Table 2.

Q.3. Type of astigmatism seen in subluxation of lens.

Ans. Irregular/compound myopic astigmatism is seen due to following mechanism:

• Weak zonules lead to relaxation of lenscapsule (which is normally in a state of stretch by zonules) making the lens more spherical along the axis with increased lens power and consequent myopia.

• Areawherezonulesarestillintact,thelensremains as such or may slightly bulge.

• Therefore,thereismoremyopiainoneaxiswhile less myopia in other axis.

Q.4. What are the diagnostic criteria for Marfan’s syndrome?

Ans. Marfan’s Disease is diagnosed according to Modified Ghent’s Criteria

In absence of family history: • Aortic root dilation (Z score >2) and

Ectopia lentis • AorticrootdilationandFBN1mutation • Aorticrootdilationandsystemicscore>7

points • Ectopia lentis and FBN1 with known

aortic root dilation In presence of family history: • Ectopia lentis and family history:

Marfan’s syndrome • Systemic score (>7 points) and family

history of Marfan’s syndrome • Aortic dilation and family history of

Marfan’s syndrome Systemic score: • Wristandthumbsign–3(Wristorthumb

sign –1) • Pectuscarinatumdeformity–2 (pectus

excavatum or chest asymmetry –1)

• Hind foot deformity–2 (plain pes planus –1)

• Pneumothorax–2 • Duralectasia–2 • Protrusioacetabuli–2 • Reduced US/LS and increased arm/

height and no severe scoliosis –1 • Scoliosisorthoracolumbarkyphosis–1 • Reducedelbowextension–1 • Facialfeatures(3/5)–1(dolichocephaly,

enophthalmos, down-slanting palpebral fissures, malar hyoplasia, retrognathia)

• Skinstriae–1 • Myopia>3diopters–1 • Mitralvalveprolapse(alltypes)–1 Maximum total: 20 points; score ≥ 7

indicates systemic involvement.

BIBLIOGRAPHY

1. Anteby I, Isaac M, BenEzra D. Hereditary subluxated lenses: Visual performances and long-term follow-up after surgery. Ophthalmology. 2003;110:1344-8.

2. Loeys BL, et al. Revised Ghent criteria for the diagnosis of Marfan syndrome (MFS) and related conditions. J Med Genet. 2010;47:476-85.

3. Nelson LB, Maumenee IH. Ectopia lentis. Surv Ophthalmol. 1982;27:143-60.

4. Nemet AY, Assia EI, Apple DJ, Barequet IS. Current concepts of ocular manifestations in Marfan syndrome. Surv Ophthalmol. 2006;51:561-75.

5. Rubin SE, Nelson LB. Ocular manifestations of autosomal dominant systemic conditions. Duane’s Clinical Ophthalmology on CD-ROM. Vol. 3. Ch. 58. Philadelphia: Lippincott Williams & Wilkins, 2006.

6. Sinha R, Sharma N, Vajpayee RB. Intralenticular bimanual irrigation: aspiration for subluxated lens in Marfan’s syndrome. J Cataract Refract Surg. 2005;31(7):1283-6.Ja

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