Care of the Patient with Strabismus: Esotropia and Exotropia

Total Page:16

File Type:pdf, Size:1020Kb

Care of the Patient with Strabismus: Esotropia and Exotropia OPTOMETRIC CLINICAL PRACTICE GUIDELINE OPTOMETRY: THE PRIMARY EYE CARE PROFESSION Doctors of optometry are independent primary health care providers who examine, diagnose, treat, and manage diseases and disorders of the visual system, the eye, and associated structures as well as diagnose related systemic conditions. Optometrists provide more than two-thirds of the primary eye care services in the United States. They are more widely distributed geographically than other eye care providers and are readily accessible for the delivery of eye and vision care services. There are approximately 36,000 full-time equivalent doctors of optometry currently in practice in the United States. Optometrists practice in more than 6,500 communities Care of the Patient with across the United States, serving as the sole primary eye care providers in more than 3,500 communities. Strabismus: The mission of the profession of optometry is to fulfill the vision and eye care needs of the public through clinical care, research, and education, all Esotropia and of which enhance the quality of life. Exotropia OPTOMETRIC CLINICAL PRACTICE GUIDELINE CARE OF THE PATIENT WITH STRABISMUS: ESOTROPIA AND EXOTROPIA Reference Guide for Clinicians Prepared by the American Optometric Association Consensus Panel on Care of the Patient with Strabismus: Robert P. Rutstein, O.D., Principal Author Martin S. Cogen, M.D. Susan A. Cotter, O.D. Kent M. Daum, O.D., Ph.D. Rochelle L. Mozlin, O.D. Julie M. Ryan, O.D. Edited by: Robert P. Rutstein, O.D., M.S. Reviewed by the AOA Clinical Guidelines Coordinating Committee: David A. Heath, O.D., Ed.M., Chair NOTE: Clinicians should not rely on the Clinical Diane T. Adamczyk, O.D. Guideline alone for patient care and management. John F. Amos, O.D., M.S. Refer to the listed references and other sources Brian E. Mathie, O.D. for a more detailed analysis and discussion of Stephen C. Miller, O.D. research and patient care information. The information in the Guideline is current as of the date of publication. It will be reviewed periodically Approved by the AOA Board of Trustees, June 28, 1995 and revised as needed. Revised 1999; reviewed 2004; revised 2010 © American Optometric Association, 2011 243 N. Lindbergh Blvd., St. Louis, MO 63141-7881 Printed in U.S.A. Strabismus: Esotropia and Exotropia iii iv Strabismus: Esotropia and Exotropia TABLE OF CONTENTS b. Signs, Symptoms, and Complications ............. 21 c. Early Detection and Prevention ....................... 21 INTRODUCTION ................................................................................... 1 6. Intermittent Exotropia ................................................ 21 a. Natural History ................................................ 21 I. STATEMENT OF THE PROBLEM ........................................... 2 b. Signs, Symptoms, and Complications ............. 21 A. Description and Classification of Strabismus ........................ 4 c. Early Detection and Prevention ....................... 22 1. Esotropia ...................................................................... 5 7. Mechanical Esotropia and Exotropia ......................... 22 a. Infantile Esotropia .............................................. 5 a. Natural History ................................................ 22 b. Acquired Esotropia ............................................ 5 b. Signs, Symptoms, and Complications ............. 23 c. Secondary Esotropia .......................................... 7 c. Early Detection and Prevention ....................... 23 d. Microesotropia ................................................... 8 8. Microtropia ................................................................ 23 2. Exotropia ..................................................................... 8 a. Natural History ................................................ 23 a. Infantile Exotropia ............................................. 9 b. Signs, Symptoms, and Complications ............. 23 b. Acquired Exotropia ............................................ 9 c. Early Detection and Prevention ....................... 24 c. Secondary Exotropia ........................................ 10 9. Sensory Esotropia ...................................................... 24 d. Microexotropia ................................................. 11 a. Natural History ................................................ 24 B. Epidemiology of Strabismus ............................................... 11 b. Signs, Symptoms, and Complications ............. 24 1. Incidence and Prevalence .......................................... 11 c. Early Detection and Prevention ....................... 24 2. Risk Factors ............................................................... 12 10. Sensory Exotropia ...................................................... 25 C. Clinical Background of Strabismus ..................................... 12 a. Natural History ................................................ 25 1. Accommodative Esotropia......................................... 12 b. Signs, Symptoms, and Complications ............. 25 a. Natural History ................................................ 12 c. Early Detection and Prevention ....................... 25 b. Signs, Symptoms, and Complications ............. 13 c. Early Detection and Prevention ....................... 14 II. CARE PROCESS ........................................................................ 26 2. Acute Esotropia and Exotropia .................................. 14 A. Diagnosis of Strabismus ...................................................... 26 a. Natural History ................................................ 14 1. Patient History ........................................................... 26 b. Signs, Symptoms, and Complications ............. 15 2. Ocular Examination ................................................... 27 c. Early Detection and Prevention ....................... 15 a. Visual Acuity .................................................. 27 3. Consecutive Esotropia and Exotropia ........................ 15 b. Ocular Motor Deviation ................................... 28 a. Natural History ................................................ 15 c. Monocular Fixation .......................................... 28 b. Signs, Symptoms, and Complications ............. 16 d. Extraocular Muscle Function ........................... 28 c. Early Detection and Prevention ....................... 16 e. Sensorimotor Fusion ........................................ 29 4. Infantile Esotropia ..................................................... 19 f. Accommodation ............................................... 29 a. Natural History ................................................ 19 g. Refraction......................................................... 30 b. Signs, Symptoms, and Complications ............. 19 h. Ocular Health Assessment and Systemic c. Early Detection and Prevention ....................... 19 Health Screening .............................................. 30 5. Infantile Exotropia ..................................................... 20 B. Management of Strabismus ................................................. 30 a. Natural History ................................................ 20 1. Basis for Treatment ................................................... 31 Strabismus: Esotropia and Exotropia v vi Strabismus: Esotropia and Exotropia 2. Available Treatment Options ..................................... 31 a. Optical Correction ............................................ 31 b. Added Lens Power ........................................... 32 c. Prisms .............................................................. 33 d. Vision Therapy ................................................ 34 e. Pharmacological Agents .................................. 35 f. Extraocular Muscle Surgery ............................ 36 g. Chemodenervation ........................................... 38 3. Management Strategies for Strabismus ..................... 38 a. Accommodative Esotropia ............................... 38 b. Acute Esotropia and Exotropia ........................ 40 c. Consecutive Esotropia and Exotropia .............. 40 d. Infantile Esotropia and Exotropia .................... 41 e. Intermittent Exotropia ...................................... 42 f. Mechanical Esotropia and Exotropia ............... 44 g. Microtropia ...................................................... 44 h. Sensory Esotropia and Exotropia ..................... 45 4. Patient Education ....................................................... 45 5. Prognosis and Follow-up ........................................... 46 CONCLUSION ..................................................................................... 47 III. REFERENCES ......................................................................... 48 IV. APPENDIX ............................................................................... 66 Figure 1: Optometric Management of the Patient with Strabismus: A Brief Flowchart ............................ 66 Figure 2: Frequency and Composition of Evaluation and Management Visits for Esotropia and Exotropia ... 67 Figure 3: ICD-10-CM Classification of Esotropia and Exotropia ............................................................. 69 Abbreviations of Commonly Used Terms ................................. 71 Glossary ..................................................................................... 72 Introduction 1 2 Strabismus: Esotropia and Exotropia INTRODUCTION
Recommended publications
  • Management of Microtropia
    Br J Ophthalmol: first published as 10.1136/bjo.58.3.281 on 1 March 1974. Downloaded from Brit. J. Ophthal. (I974) 58, 28 I Management of microtropia J. LANG Zirich, Switzerland Microtropia or microstrabismus may be briefly described as a manifest strabismus of less than 50 with harmonious anomalous correspondence. Three forms can be distinguished: primary constant, primary decompensating, and secondary. There are three situations in which the ophthalmologist may be confronted with micro- tropia: (i) Amblyopia without strabismus; (2) Hereditary and familial strabismus; (3) Residual strabismus after surgery. This may be called secondary microtropia, for everyone will admit that in most cases of convergent strabismus perfect parallelism and bifoveal fixation are not achieved even after expert treatment. Microtropia and similar conditions were not mentioned by such well-known early copyright. practitioners as Javal, Worth, Duane, and Bielschowsky. The views of Maddox (i898), that very small angles were extremely rare, and that the natural tendency to fusion was much too strong to allow small angles to exist, appear to be typical. The first to mention small residual angles was Pugh (I936), who wrote: "A patient with monocular squint who has been trained to have equal vision in each eye and full stereoscopic vision with good amplitude of fusion may in 3 months relapse into a slight deviation http://bjo.bmj.com/ in the weaker eye and the vision retrogresses". Similar observations of small residual angles have been made by Swan, Kirschberg, Jampolsky, Gittoes-Davis, Cashell, Lyle, Broadman, and Gortz. There has been much discussion in both the British Orthoptic Journal and the American Orthoptic journal on the cause of this condition and ways of avoiding it.
    [Show full text]
  • Pediatric Anisometropia: Case Series and Review
    Pediatric Anisometropia: tacles, vision therapy, and occlusion. Case two Case Series and Review is anisometropia caused by organic vision loss from optic neuritis early in life. Case three is John D. Tassinari OD, FAAO, FCOVD an infant with hyperopic anisometropia and Diplomate Binocular Vision esotropia. The esotropia did not respond to Perception and Pediatric Optometry, spectacles and home based vision therapy. American Academy of Optometry Neonatal high bilateral hyperopia that Associate Professor Western converted to anisometropia because of early University of Health Sciences onset cosmetically invisible unilateral esotropia College of Optometry is speculated. Case four describes a boy Pomona, California diagnosed with hyperopic anisometropia at age 11 months coincident with a diagnosis of pseudoesotropia. His compliance with ARTICLE prescribed spectacles was spotty until age three years. An outstanding visual outcome ABSTRACT was achieved by age five years with spectacles Background only (no occlusion therapy). Case five concerns The etiology and natural course and history a boy who acquired hyperopic anisometropia of pediatric anisometropia are incompletely because one eye experienced increasing understood. This article reviews the literature hyperopia during his toddler years. His regarding pediatric anisometropia with much response to treatment, spectacles and part of the review integrated into a case series. time occlusion with home vision therapy, was The review and case reports are intended to outstanding. Case six is an infant diagnosed elevate clinical understanding of pediatric with 2.50 diopters of hyperopic anisometropia anisometropia including and especially at age six months. Monocular home based treatment outcomes. vison developmental activities, not glasses, were prescribed. Her anisometropia vanished Case Reports three months later.
    [Show full text]
  • Binocular Vision Disorders  Prescribing Guidelines
    Prescribing for Preverbal Children Valerie M. Kattouf O.D. FAAO, FCOVD Illinois College of Optometry Associate Professor Prescribing for Preverbal Children Issues to consider: Age Visual Function Refractive Error Norms Amblyogenic Risk Factors Birth History Family History Developmental History Emmetropization A process presumed to be operative in producing a greater frequency of occurrence of emmetropia than would be expected in terms of chance distribution, as may be explained by postulating that a mechanism coordinates the formation and the development of the various components of the human eye which contribute to the total refractive power Emmetropization Passive process = nature and genetics 60% chance of myopia if 2 parents myopic (Ciuffrieda) Active process = mediated by blur and visual system compensates for blur Refractive Error Norms Highest rate of emmetropization – 1st 12-17 months Hyperopia Average refractive error in infants = +2 D > 1.50 diopters hyperopia at 5 years old – often remain hyperopic Refractive Error Norms Myopia 25% of infants are myopic Myopic Newborns (Scharf) @ 7 years 54% still myopic @ 7 years 46% emmetropic @ 7 years no hyperopia Refractive Error Norms Astigmatism Against the rule astigmatism more prevalent switches to with-the-rule with development At 3 1/2 years old astigmatism is at adult levels INFANT REFRACTION NORMS AGE SPHERE CYL 0-1mo -0.90+/-3.17 -2.02+/-1.43 2-3mo -0.47+/-2.28 -2.02+/-1.17 4-6mo -0.00+/-1.31 -2.20+/-1.15 6-9mo +0.50+/-0.99 -2.20+/-1.15 9-12mo +0.60+/-1.30 -1.64+/-0.62
    [Show full text]
  • Vision Screening Training
    Vision Screening Training Child Health and Disability Prevention (CHDP) Program State of California CMS/CHDP Department of Health Care Services Revised 7/8/2013 Acknowledgements Vision Screening Training Workgroup – comprising Health Educators, Public Health Nurses, and CHDP Medical Consultants Dr. Selim Koseoglu, Pediatric Ophthalmologist Local CHDP Staff 2 Objectives By the end of the training, participants will be able to: Understand the basic anatomy of the eye and the pathway of vision Understand the importance of vision screening Recognize common vision disorders in children Identify the steps of vision screening Describe and implement the CHDP guidelines for referral and follow-up Properly document on the PM 160 vision screening results, referrals and follow-up 3 IMPORTANCE OF VISION SCREENING 4 Why Screen for Vision? Early diagnosis of: ◦ Refractive Errors (Nearsightedness, Farsightedness) ◦ Amblyopia (“lazy eye”) ◦ Strabismus (“crossed eyes”) Early intervention is the key to successful treatment 5 Why Screen for Vision? Vision problems often go undetected because: Young children may not realize they cannot see properly Many eye problems do not cause pain, therefore a child may not complain of discomfort Many eye problems may not be obvious, especially among young children The screening procedure may have been improperly performed 6 Screening vs. Diagnosis Screening Diagnosis 1. Identifies children at 1. Identifies the child’s risk for certain eye eye condition conditions or in need 2. Allows the eye of a professional
    [Show full text]
  • Ophthalmological Findings in Children and Adolescents with Silver Russell
    Ophthalmological findings in children and adolescents with Silver Russell Syndrome Marita Andersson Gronlund, Jovanna Dahlgren, Eva Aring, Maria Kraemer, Ann Hellstrom To cite this version: Marita Andersson Gronlund, Jovanna Dahlgren, Eva Aring, Maria Kraemer, Ann Hellstrom. Oph- thalmological findings in children and adolescents with Silver Russell Syndrome. British Journal of Ophthalmology, BMJ Publishing Group, 2010, 95 (5), pp.637. 10.1136/bjo.2010.184457. hal- 00588358 HAL Id: hal-00588358 https://hal.archives-ouvertes.fr/hal-00588358 Submitted on 23 Apr 2011 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Ophthalmological findings in children and adolescents with Silver Russell Syndrome M Andersson Grönlund, MD, PhD1, J Dahlgren, MD, PhD2, E Aring, CO, PhD1, M Kraemer, MD1, A Hellström, MD, PhD1 1Institute of Neuroscience and Physiology/Ophthalmology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden. 2Institute for the Health of Women and Children, Gothenburg Paediatric Growth Research Centre (GP-GRC), The Sahlgrenska
    [Show full text]
  • Article • a Case Series in Optometric Management of Diverse Vertical
    Article • A Case Series in Optometric Management of Diverse Vertical Deviations Darah McDaniel-Chandler, OD • Southern College of Optometry Memphis, Tennessee ABSTRACT Background: Vertical deviations present in diverse patient populations with a multitude of puzzling symptoms and complaints. Many patients with vertical deviations have visited numerous doctors looking for an explanation for their symptoms of dizziness, headaches, motion sickness, and double vision. Vertical deviations may be apparent in the clinical optometric exam sequence, but at other times, additional testing must be performed to uncover a vertical heterophoria, including fixation disparity, vertical vergences, a period of diagnostic occlusion, or Maddox rod. Case Report: Three case reports are reviewed with diverse presentations of vertical deviations. The first case report outlines Patient A, a 51-year-old female who presented with dizziness along with a latent hyperphoria that was not apparent on the initial clinical examination. The second case report outlines Patient B, a 52-year-old female who presented with a longstanding large-angle vertical strabismus with strabismic amblyopia in the right eye. The third case report outlines Patient C, a 61-year-old female who presented with intermittent vertical diplopia following a cerebrovascular accident. The three cases all underwent vision therapy or vision therapy in combination with prismatic correction, and all three cases experienced symptom reduction following treatment with optometric vision rehabilitation. Conclusion:
    [Show full text]
  • Routine Eye Examination
    CET Continuing education Routine eye examination Part 3 – Binocular assessment In the third part of our series on the eye examination, Andrew Franklin and Bill Harvey look at the assessment and interpretation of binocular status. Module C8290, one general CET point, suitable for optometrists and DOs he assessment of binocular previous question. Leading questions function is often one of the should be avoided, especially when weaker areas of a routine, dealing with children. If they are out if observation of candidates of line ask the patient ‘Which one is out in the professional qualifica- of line with the X?’ Ttions examination is any guide. Tests are You should know before you start the done for no clearly logical reason, often test which line is seen by which eye. because they always have been, and in If you cannot remember it from last an order which defeats the object of the time, simply look at the target through testing. Binocular vision seems to be one the visor yourself (Figure 1). Even if of those areas that practitioners shy away you think you can remember, check from, and students often take an instant anyway, as it is possible for the polarisa- dislike to. Many retests and subsequent tion of the visor not to match that of the remakes of spectacles are the result of a Mallett Unit at distance or near or both, practitioner overlooking the effects of a Figure 1 A distance fixation disparity target especially if the visor is a replacement. change of prescription on the binocular If both eyes can see both bars, nobody status of the patient.
    [Show full text]
  • Cranial Nerve Palsy
    Cranial Nerve Palsy What is a cranial nerve? Cranial nerves are nerves that lead directly from the brain to parts of our head, face, and trunk. There are 12 pairs of cranial nerves and some are involved in special senses (sight, smell, hearing, taste, feeling) while others control muscles and glands. Which cranial nerves pertain to the eyes? The second cranial nerve is called the optic nerve. It sends visual information from the eye to the brain. The third cranial nerve is called the oculomotor nerve. It is involved with eye movement, eyelid movement, and the function of the pupil and lens inside the eye. The fourth cranial nerve is called the trochlear nerve and the sixth cranial nerve is called the abducens nerve. They each innervate an eye muscle involved in eye movement. The fifth cranial nerve is called the trigeminal nerve. It provides facial touch sensation (including sensation on the eye). What is a cranial nerve palsy? A palsy is a lack of function of a nerve. A cranial nerve palsy may cause a complete or partial weakness or paralysis of the areas served by the affected nerve. In the case of a cranial nerve that has multiple functions (such as the oculomotor nerve), it is possible for a palsy to affect all of the various functions or only some of the functions of that nerve. What are some causes of a cranial nerve palsy? A cranial nerve palsy can occur due to a variety of causes. It can be congenital (present at birth), traumatic, or due to blood vessel disease (hypertension, diabetes, strokes, aneurysms, etc).
    [Show full text]
  • Strabismus, Amblyopia & Leukocoria
    Strabismus, Amblyopia & Leukocoria [ Color index: Important | Notes: F1, F2 | Extra ] EDITING FILE ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Objectives: ➢ Not given. Done by: Jwaher Alharbi, Farrah Mendoza. ​ ​ Revised by: Rawan Aldhuwayhi ​ Resources: Slides + Notes + 434 team. ​ ​ NOTE: F1& F2 doctors are different, the doctor who gave F2 said she is in the exam committee so focus on her notes Amblyopia ● Definition Decrease in visual acuity of one eye without the presence of an organic cause that explains that decrease ​ ​ in visual acuity. He never complaints of anything and his family never noticed any abnormalities ​ ● Incidence The most common cause of visual loss under 20 years of life (2-4% of the general population) ● How? Cortical ignorance of one eye. This will end up having a lazy eye ​ ● binocular vision It is achieved by the use of the two eyes together so that separate and slightly dissimilar images arising in each eye are appreciated as a single image by the process of fusion. It’s importance 1. Stereopsis 2. Larger field If there is no coordination between the two eyes the person will have double vision and confusion so as a compensatory mechanism for double vision the brain will cause suppression. The visual pathway is a plastic system that continues to develop during childhood until around 6-9 years of age. During this time, the wiring between the retina and visual cortex is still developing. Any visual problem during this critical period, such as a refractive error or strabismus can mess up this developmental wiring, resulting in permanent visual loss that can't be fixed by any corrective means when they are older Why fusion may fail ? 1.
    [Show full text]
  • Updates on Myopia
    Updates on Myopia A Clinical Perspective Marcus Ang Tien Y. Wong Editors Updates on Myopia Marcus Ang • Tien Y. Wong Editors Updates on Myopia A Clinical Perspective Editors Marcus Ang Tien Y. Wong Singapore National Eye Center Singapore National Eye Center Duke-NUS Medical School Duke-NUS Medical School National University of Singapore National University of Singapore Singapore Singapore This book is an open access publication. ISBN 978-981-13-8490-5 ISBN 978-981-13-8491-2 (eBook) https://doi.org/10.1007/978-981-13-8491-2 © The Editor(s) (if applicable) and The Author(s) 2020, corrected publication 2020 Open Access This book is licensed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license and indicate if changes were made. The images or other third party material in this book are included in the book's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the book's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. The use of general descriptive names, registered names, trademarks, service marks, etc. in this publication does not imply, even in the absence of a specifc statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use.
    [Show full text]
  • Approved and Unapproved Abbreviations and Symbols For
    Facility: Illinois College of Optometry and Illinois Eye Institute Policy: Approved And Unapproved Abbreviations and Symbols for Medical Records Manual: Information Management Effective: January 1999 Revised: March 2009 (M.Butz) Review Dates: March 2003 (V.Conrad) March 2008 (M.Butz) APPROVED AND UNAPPROVED ABBREVIATIONS AND SYMBOLS FOR MEDICAL RECORDS PURPOSE: To establish a database of acceptable ocular and medical abbreviations for patient medical records. To list the abbreviations that are NOT approved for use in patient medical records. POLICY: Following is the list of abbreviations that are NOT approved – never to be used – for use in patient medical records, all orders, and all medication-related documentation that is either hand-written (including free-text computer entry) or pre-printed: DO NOT USE POTENTIAL PROBLEM USE INSTEAD U (unit) Mistaken for “0” (zero), the Write “unit” number “4”, or “cc” IU (international unit) Mistaken for “IV” (intravenous) Write “international unit” or the number 10 (ten). Q.D., QD, q.d., qd (daily) Mistaken for each other Write “daily” Q.O.D., QOD, q.o.d., qod Period after the Q mistaken for Write (“every other day”) (every other day) “I” and the “O” mistaken for “I” Trailing zero (X.0 mg) ** Decimal point is missed. Write X mg Lack of leading zero (.X mg) Decimal point is missed. Write 0.X mg MS Can mean morphine sulfate or Write “morphine sulfate” or magnesium sulfate “magnesium sulfate” MSO4 and MgSO4 Confused for one another Write “morphine sulfate” or “magnesium sulfate” ** Exception: A trailing zero may be used only where required to demonstrate the level of precision of the value being reported, such as for laboratory results, imaging studies that report size of lesions, or catheter/tube sizes.
    [Show full text]
  • Management of Vith Nerve Palsy-Avoiding Unnecessary Surgery
    MANAGEMENT OF VITH NERVE PALSY-AVOIDING UNNECESSARY SURGERY P. RIORDAN-E VA and J. P. LEE London SUMMARY for unrecovered VIth nerve palsy must involve a trans­ Unresolved Vlth nerve palsy that is not adequately con­ position procedure3.4. The availability of botulinum toxin trolled by an abnormal head posture or prisms can be to overcome the contracture of the ipsilateral medial rectus 5 very suitably treated by surgery. It is however essential to now allows for full tendon transplantation techniques -7, differentiate partially recovered palsies, which are with the potential for greatly increased improvements in amenable to horizontal rectus surgery, from unrecovered final fields of binocular single vision, and deferment of palsies, which must be treated initially by a vertical any necessary surgery to the medial recti, which is also muscle transposition procedure. Botulinum toxin is a likely to improve the final outcome. valuable tool in making this distinction. It also facilitates This study provides definite evidence, from a large full tendon transposition in unrecovered palsies, which series of patients, of the potential functional outcome from appears to produce the best functional outcome of all the the surgical treatment of unresolved VIth nerve palsy, transposition procedures, with a reduction in the need for together with clear guidance as to the forms of surgery that further surgery. A study of the surgical management of 12 should be undertaken in specific cases. The fundamental patients with partially recovered Vlth nerve palsy and 59 role of botulinum toxin in establishing the degree of lateral patients with unrecovered palsy provides clear guidelines rectus function and hence the correct choice of initial sur­ on how to attain a successful functional outcome with the gery, and as an adjunct to transposition surgery for unre­ minimum amount of surgery.
    [Show full text]