This document summarizes exotropia, an outward deviation of the eye. It discusses the different types of exotropia, including infantile exotropia characterized by a large angle constant exodeviation often first noticed before age 6 months. Intermittent exotropia, the most common type, involves occasional outward deviation that varies in frequency and duration. Evaluation of exotropia involves assessing visual acuity and eye alignment with cover tests. Treatment depends on the type but may include refractive correction, orthoptic exercises, patching, or strabismus surgery.
Purpose: We report a rare case of a 2 - year-old child with ectopia lentis and potential Marfan syndrome (MFS) and discuss her management.
Methods: A 2 - year - old female with no signifi cant past medical history was brought in by her mother after complaints that the child has recently been holding everything close to her eyes while simultaneously shifting her head down. Her mother reported no history of pain or trauma. The child’s family history was negative for ectopia lentis or MFS.
:Extraocular foreign bodies (EOFBs) are a common presentation to the emergency
department (ED). Given that inadequate management can result in severe complications including visual
impairment, ED clinicians may be overly cautious and often schedule patient reviews in the ED even
where it is unnecessary, placing a burden on hospital resources.
http://igolenses.co.uk
After reading the outcomes of the LORIC, CRAYON and SMART studies, two US opticians then undertook their own investigation into whether Overnight Vision Correction (OVC) can slow down or halt the further development of short-sightedness once patients are fitted with overnight ortho-k corrective contact lenses. T
Purpose: We report a rare case of a 2 - year-old child with ectopia lentis and potential Marfan syndrome (MFS) and discuss her management.
Methods: A 2 - year - old female with no signifi cant past medical history was brought in by her mother after complaints that the child has recently been holding everything close to her eyes while simultaneously shifting her head down. Her mother reported no history of pain or trauma. The child’s family history was negative for ectopia lentis or MFS.
:Extraocular foreign bodies (EOFBs) are a common presentation to the emergency
department (ED). Given that inadequate management can result in severe complications including visual
impairment, ED clinicians may be overly cautious and often schedule patient reviews in the ED even
where it is unnecessary, placing a burden on hospital resources.
http://igolenses.co.uk
After reading the outcomes of the LORIC, CRAYON and SMART studies, two US opticians then undertook their own investigation into whether Overnight Vision Correction (OVC) can slow down or halt the further development of short-sightedness once patients are fitted with overnight ortho-k corrective contact lenses. T
Myopic shift and preoperative axial length after congenital cataract surgery in Peruvian patients - The Association for Research in Vision and Ophthalmology Meeting (ARVO) 2018 Honolulu, Hawaii - Poster presentation
Background: Strabismic amblyopia is characterized by an imbalance of the sensorial and motor system. Differences between both
eyes due to squinting during 1st months of life can originate an entire fovea fixation and ARC, which is a binocular condition generated
by the absence of a correct bi-foveal fixation [2]. Accommodative esotropia usually presents between 2 and 4 years of age with an
increase in accommodative needs and is directly linked to the amount of hypermetropia [9]. Although patching remains the gold
standard therapy of amblyopia, several new treatment options have emerged over the years. These include refractive adaptation,
atropine penalization, and several binocular activities with varying success rates [10].
Case Report: 6-year-old male presented with complaints of inward deviation, and blurring of vision for distance and near. A proper
squint evaluation was performed to determine the presence of the type of squint. Accommodative esotropia with amblyopia in one
eye was reported. Synoptophorehaidinger brushes were recommended for foveal stimulation for the amblyopic eye followed by
patching. The patient reported good compliance and significant vision improvement in the amblyopic eye and no longer blur and
deviation with glasses were observed.
Conclusion: Accommodative esotropia with amblyopia showed substantial improvement with the help of Haidinger brushes in the
amblyopic eye. A combination of patching and Haidinger brushes is an efficacious approach for achieving an improvement in visual
acuity and binocular function in strabismic amblyopia.
Keywords: Accommodative Esotropia; Strabismic Amblyopia; Haidinger Brushes; Synoptophore
April 2019 . Cataracts secondary to intraocular diseases are complicated cata...Vinitkumar MJ
DEMOGRAPHIC PROFILES AND AETIOLOGY OF COMPLICATED CATARACTS: A HOSPITAL BASED STUDY.
Aim: To study demographic profiles and aetiology of complicated cataracts in patients presenting to the Out-Patient Department of B. P. Koirala Lions Centre for Ophthalmic Studies (BPKLCOS).
Ocular hypotony following reenclavation of a partially dislocated (disenclavated) retropupillary iris-clipped intraocular lens in a child with Marfan Syndrome was presented and won best paper in the Pediatric Ophthalmology and Genetics Category at the 6th Asean Ophthalmology Congress in conjunction with the Philippine Academy of Ophthalmology Annual Convention, October 2023, SMX Convention Center, Pasay City, Philippines.
Corneal opacities in infants and children pose unique
management challenges. Penetrating Keratoplasty (PKP) has been used in order to clear the visual axis and prevent amblyopia, but has been historically associated with high rates of graft failure and other complications
Overview of glaucoma from an engineering perspective for ophthalmologic technology used for diagnosis, disease management and eventually for personalized medicine.
External download link: https://www.dropbox.com/s/i7qmd5ecj8c247x/glaucoma_overview.pdf?dl=0
Crouzon syndrome is the most common syndrome in the craniosynostosis group. Crouzon syndrome accounts for about 4.8 of all cases. It usually has autosomal dominant inheritance with full penetrance and variable expressiveness from subtle to severe forms and is caused by maxillary hypoplasia with craniosynostosis, proptosis, and relative mandibular protrusion. be characterized. Mutations in the fibroblast growth factor receptor 2 gene have been implicated in the development of this rare genetic disorder. Our work reports the diagnosis of this rare syndrome in young patients based on clinical and radiological features. Prompt and timely treatment of the syndrome has allowed this patient to lead a normal life despite the syndrome. Dr. Kala Barathi. S | Mr. Azrudheen. B "Crouzon Syndrome: A Case Report" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-7 | Issue-1 , February 2023, URL: https://www.ijtsrd.com/papers/ijtsrd53851.pdf Paper URL: https://www.ijtsrd.com/medicine/nursing/53851/crouzon-syndrome-a-case-report/dr-kala-barathi-s
Clinical study of fundal changes in high myopiaiosrjce
IOSR Journal of Dental and Medical Sciences is one of the speciality Journal in Dental Science and Medical Science published by International Organization of Scientific Research (IOSR). The Journal publishes papers of the highest scientific merit and widest possible scope work in all areas related to medical and dental science. The Journal welcome review articles, leading medical and clinical research articles, technical notes, case reports and others.
Congenital Glaucoma is one of the most common causes of irreversible childhood blindness. This presentation covers this topic in detail that can aid physicians in effective patient care.
PS: The slides in the preview look skewed, download the presentation to view the font used in Office 2012 and upwards.
PURPOSE: To evaluate the long-term safety and effica- cy of Ferrara intrastromal corneal ring segments (ICRS) (Ferrara Ring; AJL, Boecillo, Spain) in patients with kera- toconus.
This ppt will explain about how to write a grant proposal, the steps and what to lookout for. It provides help for those who are implementing a grant proposal
Myopic shift and preoperative axial length after congenital cataract surgery in Peruvian patients - The Association for Research in Vision and Ophthalmology Meeting (ARVO) 2018 Honolulu, Hawaii - Poster presentation
Background: Strabismic amblyopia is characterized by an imbalance of the sensorial and motor system. Differences between both
eyes due to squinting during 1st months of life can originate an entire fovea fixation and ARC, which is a binocular condition generated
by the absence of a correct bi-foveal fixation [2]. Accommodative esotropia usually presents between 2 and 4 years of age with an
increase in accommodative needs and is directly linked to the amount of hypermetropia [9]. Although patching remains the gold
standard therapy of amblyopia, several new treatment options have emerged over the years. These include refractive adaptation,
atropine penalization, and several binocular activities with varying success rates [10].
Case Report: 6-year-old male presented with complaints of inward deviation, and blurring of vision for distance and near. A proper
squint evaluation was performed to determine the presence of the type of squint. Accommodative esotropia with amblyopia in one
eye was reported. Synoptophorehaidinger brushes were recommended for foveal stimulation for the amblyopic eye followed by
patching. The patient reported good compliance and significant vision improvement in the amblyopic eye and no longer blur and
deviation with glasses were observed.
Conclusion: Accommodative esotropia with amblyopia showed substantial improvement with the help of Haidinger brushes in the
amblyopic eye. A combination of patching and Haidinger brushes is an efficacious approach for achieving an improvement in visual
acuity and binocular function in strabismic amblyopia.
Keywords: Accommodative Esotropia; Strabismic Amblyopia; Haidinger Brushes; Synoptophore
April 2019 . Cataracts secondary to intraocular diseases are complicated cata...Vinitkumar MJ
DEMOGRAPHIC PROFILES AND AETIOLOGY OF COMPLICATED CATARACTS: A HOSPITAL BASED STUDY.
Aim: To study demographic profiles and aetiology of complicated cataracts in patients presenting to the Out-Patient Department of B. P. Koirala Lions Centre for Ophthalmic Studies (BPKLCOS).
Ocular hypotony following reenclavation of a partially dislocated (disenclavated) retropupillary iris-clipped intraocular lens in a child with Marfan Syndrome was presented and won best paper in the Pediatric Ophthalmology and Genetics Category at the 6th Asean Ophthalmology Congress in conjunction with the Philippine Academy of Ophthalmology Annual Convention, October 2023, SMX Convention Center, Pasay City, Philippines.
Corneal opacities in infants and children pose unique
management challenges. Penetrating Keratoplasty (PKP) has been used in order to clear the visual axis and prevent amblyopia, but has been historically associated with high rates of graft failure and other complications
Overview of glaucoma from an engineering perspective for ophthalmologic technology used for diagnosis, disease management and eventually for personalized medicine.
External download link: https://www.dropbox.com/s/i7qmd5ecj8c247x/glaucoma_overview.pdf?dl=0
Crouzon syndrome is the most common syndrome in the craniosynostosis group. Crouzon syndrome accounts for about 4.8 of all cases. It usually has autosomal dominant inheritance with full penetrance and variable expressiveness from subtle to severe forms and is caused by maxillary hypoplasia with craniosynostosis, proptosis, and relative mandibular protrusion. be characterized. Mutations in the fibroblast growth factor receptor 2 gene have been implicated in the development of this rare genetic disorder. Our work reports the diagnosis of this rare syndrome in young patients based on clinical and radiological features. Prompt and timely treatment of the syndrome has allowed this patient to lead a normal life despite the syndrome. Dr. Kala Barathi. S | Mr. Azrudheen. B "Crouzon Syndrome: A Case Report" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-7 | Issue-1 , February 2023, URL: https://www.ijtsrd.com/papers/ijtsrd53851.pdf Paper URL: https://www.ijtsrd.com/medicine/nursing/53851/crouzon-syndrome-a-case-report/dr-kala-barathi-s
Clinical study of fundal changes in high myopiaiosrjce
IOSR Journal of Dental and Medical Sciences is one of the speciality Journal in Dental Science and Medical Science published by International Organization of Scientific Research (IOSR). The Journal publishes papers of the highest scientific merit and widest possible scope work in all areas related to medical and dental science. The Journal welcome review articles, leading medical and clinical research articles, technical notes, case reports and others.
Congenital Glaucoma is one of the most common causes of irreversible childhood blindness. This presentation covers this topic in detail that can aid physicians in effective patient care.
PS: The slides in the preview look skewed, download the presentation to view the font used in Office 2012 and upwards.
PURPOSE: To evaluate the long-term safety and effica- cy of Ferrara intrastromal corneal ring segments (ICRS) (Ferrara Ring; AJL, Boecillo, Spain) in patients with kera- toconus.
This ppt will explain about how to write a grant proposal, the steps and what to lookout for. It provides help for those who are implementing a grant proposal
VITREOUS AND RETINA PEDIATRIC OCULAR DIESEASES.pptxreshmasu
This ppt explains about the various pediatric ocular diseases of retina and vitreous:
1.Retinoblastoma
2.Persistent hyperplastic primary vitreous (PHPV)
3.Best disease
4.Coats disease
5.Retinopathy of prematurity
6.Stargardts disease
7.Juvenile retinoschisis
8.Familial exudative vitreoretinopathy
CARE AND MAINTANENCE OF SOFT CONTACT LENS.pptxreshmasu
This ppt will explain in detail regarding the disinfection system including hydrogen peroxide system and other methods of care and maintenance of soft contact lens
Nutraceutical market, scope and growth: Herbal drug technologyLokesh Patil
As consumer awareness of health and wellness rises, the nutraceutical market—which includes goods like functional meals, drinks, and dietary supplements that provide health advantages beyond basic nutrition—is growing significantly. As healthcare expenses rise, the population ages, and people want natural and preventative health solutions more and more, this industry is increasing quickly. Further driving market expansion are product formulation innovations and the use of cutting-edge technology for customized nutrition. With its worldwide reach, the nutraceutical industry is expected to keep growing and provide significant chances for research and investment in a number of categories, including vitamins, minerals, probiotics, and herbal supplements.
Richard's aventures in two entangled wonderlandsRichard Gill
Since the loophole-free Bell experiments of 2020 and the Nobel prizes in physics of 2022, critics of Bell's work have retreated to the fortress of super-determinism. Now, super-determinism is a derogatory word - it just means "determinism". Palmer, Hance and Hossenfelder argue that quantum mechanics and determinism are not incompatible, using a sophisticated mathematical construction based on a subtle thinning of allowed states and measurements in quantum mechanics, such that what is left appears to make Bell's argument fail, without altering the empirical predictions of quantum mechanics. I think however that it is a smoke screen, and the slogan "lost in math" comes to my mind. I will discuss some other recent disproofs of Bell's theorem using the language of causality based on causal graphs. Causal thinking is also central to law and justice. I will mention surprising connections to my work on serial killer nurse cases, in particular the Dutch case of Lucia de Berk and the current UK case of Lucy Letby.
Seminar of U.V. Spectroscopy by SAMIR PANDASAMIR PANDA
Spectroscopy is a branch of science dealing the study of interaction of electromagnetic radiation with matter.
Ultraviolet-visible spectroscopy refers to absorption spectroscopy or reflect spectroscopy in the UV-VIS spectral region.
Ultraviolet-visible spectroscopy is an analytical method that can measure the amount of light received by the analyte.
This presentation explores a brief idea about the structural and functional attributes of nucleotides, the structure and function of genetic materials along with the impact of UV rays and pH upon them.
Earliest Galaxies in the JADES Origins Field: Luminosity Function and Cosmic ...Sérgio Sacani
We characterize the earliest galaxy population in the JADES Origins Field (JOF), the deepest
imaging field observed with JWST. We make use of the ancillary Hubble optical images (5 filters
spanning 0.4−0.9µm) and novel JWST images with 14 filters spanning 0.8−5µm, including 7 mediumband filters, and reaching total exposure times of up to 46 hours per filter. We combine all our data
at > 2.3µm to construct an ultradeep image, reaching as deep as ≈ 31.4 AB mag in the stack and
30.3-31.0 AB mag (5σ, r = 0.1” circular aperture) in individual filters. We measure photometric
redshifts and use robust selection criteria to identify a sample of eight galaxy candidates at redshifts
z = 11.5 − 15. These objects show compact half-light radii of R1/2 ∼ 50 − 200pc, stellar masses of
M⋆ ∼ 107−108M⊙, and star-formation rates of SFR ∼ 0.1−1 M⊙ yr−1
. Our search finds no candidates
at 15 < z < 20, placing upper limits at these redshifts. We develop a forward modeling approach to
infer the properties of the evolving luminosity function without binning in redshift or luminosity that
marginalizes over the photometric redshift uncertainty of our candidate galaxies and incorporates the
impact of non-detections. We find a z = 12 luminosity function in good agreement with prior results,
and that the luminosity function normalization and UV luminosity density decline by a factor of ∼ 2.5
from z = 12 to z = 14. We discuss the possible implications of our results in the context of theoretical
models for evolution of the dark matter halo mass function.
Deep Behavioral Phenotyping in Systems Neuroscience for Functional Atlasing a...Ana Luísa Pinho
Functional Magnetic Resonance Imaging (fMRI) provides means to characterize brain activations in response to behavior. However, cognitive neuroscience has been limited to group-level effects referring to the performance of specific tasks. To obtain the functional profile of elementary cognitive mechanisms, the combination of brain responses to many tasks is required. Yet, to date, both structural atlases and parcellation-based activations do not fully account for cognitive function and still present several limitations. Further, they do not adapt overall to individual characteristics. In this talk, I will give an account of deep-behavioral phenotyping strategies, namely data-driven methods in large task-fMRI datasets, to optimize functional brain-data collection and improve inference of effects-of-interest related to mental processes. Key to this approach is the employment of fast multi-functional paradigms rich on features that can be well parametrized and, consequently, facilitate the creation of psycho-physiological constructs to be modelled with imaging data. Particular emphasis will be given to music stimuli when studying high-order cognitive mechanisms, due to their ecological nature and quality to enable complex behavior compounded by discrete entities. I will also discuss how deep-behavioral phenotyping and individualized models applied to neuroimaging data can better account for the subject-specific organization of domain-general cognitive systems in the human brain. Finally, the accumulation of functional brain signatures brings the possibility to clarify relationships among tasks and create a univocal link between brain systems and mental functions through: (1) the development of ontologies proposing an organization of cognitive processes; and (2) brain-network taxonomies describing functional specialization. To this end, tools to improve commensurability in cognitive science are necessary, such as public repositories, ontology-based platforms and automated meta-analysis tools. I will thus discuss some brain-atlasing resources currently under development, and their applicability in cognitive as well as clinical neuroscience.
2. INTRODUCTION
Outward deviation of the eye
Visual axis deviated laterally and fovea is rotated nasally
Exodeviations=Divergent strabismus
10/24/2023
2
3. PREVALENCE
The estimated prevalence of any strabismus, exotropia, and esotropia
was 1.93% (1.64-2.21), 1.23% (1.00-1.46), and 0.77% (0.59-0.95),
respectively (1)
Intermittent exotropia is the most common type of exotropia, affecting
nearly 1% of the population
Exotropia has been reported to be more prevalent among Asian and
African American populations than among Caucasians women comprise
60 -70% of patients with exotropia (2)
10/24/2023
1. Hashemi H, Pakzad R, Heydarian S, Yekta A, Aghamirsalim M, Shokrollahzadeh F, Khoshhal F, Pakbin M, Ramin S, Khabazkhoob M. Global and regional
prevalence of strabismus: a comprehensive systematic review and meta-analysis. Strabismus. 2019
2. Azam P, Nausheen N, Fahim MF. Prevalence of Strabismus and its type in Pediatric age group 6-15 years in a tertiary eye care hospital, Karachi. Biom
Biostat Int J. 2019
3
4. SYMPTOMS
Eyes turned outward some or all the time
Decreased vision in the deviated eye
Squinting
Eyestrain
Headaches
Double vision
Decreased depth perception
10/24/2023
Von Noorden, Binocular vision and ocular motility, sixth edition
4
7. EVALUATION
Visual acuity
Cycloplegic refraction
Hirschberg test
Cover test
Prism bar cover test
Binocular vision test
Stereopsis
Fusional amplitudes
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7
8. PSEUDOEXOTROPIA
The term pseudoexotropia refers to a false appearance
of exodeviation when in fact the eyes are properly
aligned
Wide inter pupillary distance
Large angle positive kappa – hyperopia/ROP
Due to anatomical or mechanical factors within the orbit
Can be due to excessive tonic divergence
No treatment is required for pseudoexotropia.
10/24/2023
8
9. ESSENTIAL INFANTILE EXOTROPIA
Onset is before age 6 months and persists beyond this age
It is classified as primary infantile exotropia
Parents and other persons usually see the exodeviation because of the
large degree of deviation
early onset intermittent exotropia
10/24/2023
AAO. Strabismus: Infantile Exotropia. ByAlvina Pauline D. Santiago, MD.
2015
9
10. Features:
• Large angle constant exodeviation is mostly more than 35PD
• Fusion will be poor
• It occurs in patients with craniofacial anomalies, cerebral palsy,
developmental delay
10/24/2023
10
11. 10/24/2023
AAO. Strabismus: Infantile Exotropia. ByAlvina Pauline D.
Santiago, MD. 2015
11
Infantile exotropia. A, This 10-month-old infant with
infantile exotropia also shows developmental
delay. B, Krimsky testing using 2 base-in prisms to
measure the large exotropia.
12. Amblyopia therapy should be started at the earliest possible.
Surgical treatment should be planned after six months of age and usually
better before 24 months.
There are few studies of infantile exotropia treated with botox
Bilateral lateral rectus recession or unilateral recession- resection
procedure may be preferred in the amblyopic or the non-dominant eye.
10/24/2023
12
13. INTERMITTENT EXOTROPIA
Intermittent exotropia is the most common type of strabismus
It is characterized by occasional outward deviation of one or alternate
eyes.
Frequency, duration of deviation, and control vary from individual to
individual
Manifest with attention, fatigue, end of the day (loose ability to convert)
Exposure to bright light cause reflex closure of one eye
10/24/2023
Kaur K, Gurnani B. Intermittent Exotropia. [Updated 2022 Dec 6]. In: StatPearls [Internet]. Treasure
Island (FL): StatPearls Publishing; 2022 Jan-.
13
16. IDS-CONTROL SCORE
1. The Newcastle control score
It was developed by incorporating subjective (home control) and objective (clinic
control) criteria into a control rating scale. (1)
2. The PEDIG IXT score
Pediatric eye disease investigator group
This new scale for assessing control in children with intermittent exotropia can be
easily applied in the office setting and characterizes the wide range of control in this
disorder. (2)
10/24/2023
1. Haggerty H, Richardson S, Hrisos S, Strong NP, Clarke MP. The Newcastle Control Score: a new method of grading the severity of intermittent distance exotropia. Br
J Ophthalmol. 2004 Feb;88(2):233-5. doi: 10.1136/bjo.2003.027615. PMID: 14736781; PMCID: PMC1772020.
2. Mohney BG, Holmes JM. An office-based scale for assessing control in intermittent exotropia. Strabismus. 2006 Sep;14(3):147-50. doi: 10.1080/09273970600894716.
PMID: 16950743; PMCID: PMC2699414
16
19. 10/24/2023
19
PBCT (N) 20PD
PBCT (D) 35 PD
remeasure
Yes
PBCT (N) 30PD
PBCT (D)35 PD
No
PBCT (N) becomes
higher-pseudo
divergence excess
True
divergence
excess
PBCT (N)
same after +3
lens – normal
AC/A
PBCT (N)
higher after +3
lens – high
AC/A
Monocular
patch test
(45 min)
Change in findings?
20. Refractive error: overcorrecting minus lens
Orthoptics: These may be used to improve the control of the deviation
Part-time occlusion of the non-deviating eye may improve control in some
patients
Base in prisms
Unilateral lateral rectus recession and medial rectus resection
10/24/2023
Kaur K, Gurnani B. Exotropia. [Updated 2023 Feb 13]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls
Publishing; 2023 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK578185/
20
21. SENSORY EXOTROPIA
Secondary (sensory) exotropia is the result of monocular
or binocular visual impairment by acquired lesions, such
as cataract or other media opacity
Treatment consists of correction of the visual deficit, if
possible, followed by surgery if appropriate
A minority of patients develop intractable diplopia due to
loss of fusion
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21
22. CONSECUTIVE EXOTROPIA
This occurs when a person who was
formerly esotropic becomes exotropic.
In most cases this occurs from a surgical
overcorrection of the esotropia (beyond 3-4
weeks)
Treatment is correction of refractive error if
present. Surgery can be done for cosmetic
purposes.
10/24/2023
22
23. INCOMITANT EXOTROPIA
Incomitant deviation implies that the divergent deviation of the visual axis
is variable in different gazes.
These are often associated with the limitation of extraocular movements
resulting either from paralytic or a restrictive etiology.
Incomitant Exotropia Differentials
• Third nerve palsy
• Duane retraction syndrome
• Crouzon syndrome
• Restrictive pathologies (thyroid eye disease, medial wall blowout
fracture, myositis, myasthenia gravis)
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23
Kaur K, Gurnani B. Exotropia. [Updated 2023 Feb 13]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls
Publishing; 2023 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK578185/
Concomitant deviation means that the divergent deviation of the visual axis remains the same in all positions of gaze. Incomitant deviation implies that the divergent deviation of the visual axis is variable in different gazes.
A patient with exotropia should undergo a detailed physical and ocular examination. The crucial clinical evaluation points in any patient with exotropia should include the following:
Visual acuity – It is imperative to record the visual acuity or fixation patterns using age-appropriate methods. Any anisometropia or amblyopia should always be ruled out.
Cycloplegic refraction - should ideally be repeated every six months in any patient presenting squinting eyes.
Corneal reflex/Hirschberg test should assess the ocular alignment at 1/3 meter, 6 meters, and far distance.
Cover test – should be done to assess eyes' alignment following breakage of fusion. This also needs to be done at 1/3 meter, 6 meters, and far distance.
Prism cover test – prism bar cover test should be performed in all cardinal positions of gaze and for both near and distance. It is essential to look for lateral gaze incomitance or any associated A or V pattern. Lateral gaze incomitance is diagnosed when there is a 20% reduction in squint angle in the lateral gazes.
Measurement of squint should also be done at a far distance beyond 6 meters. At times a larger angle of deviation may be detected when tested at a far distance.
Binocular single vision (BSV) – Should be assessed for distance and near separately with worth four dots test. BSV should be repeated at each visit and documented, as it might worsen over time.
Stereopsis – Should be tested during the phoric phase. A progressive decline significantly in the distance stereopsis is an early indication for surgical intervention.
An occlusion test is essential when the patient presents with an intermittent exotropia that is present only for distance or a distance deviation that exceeds near deviation by 15 prism diopters or more. In this test, one eye is occluded for a minimum of 45 minutes duration, and the squint measurements are repeated using the prism bar cover test. 18929306 If the post occlusion near the angle of deviation increases markedly, this is labeled as simulated divergence excess exotropia. If the near deviation remains unchanged, this is labeled as true divergence excess exotropia. This helps in differentiating between true and simulated divergence excess.
+3 diopter spherical lens test – In this test, the exodeviations for near are measured with and without a +3 diopter spherical lens placed in front of the exotropic eye while using an accommodative target, and the AC/A ratio can be estimated. The AC/A ratio predicts how a patient will respond to plus lenses should a surgical overcorrection result.[19]
Fusional amplitudes – Convergence and divergence amplitudes should be measured. Most patients with intermittent exotropia have good convergence amplitudes for near and poor to good amplitudes for distance. Divergence amplitudes are normal in these patients.
Positive angle kappa without other ocular abnormalities.
Positive angle kappa together with other abnormalities such as temporal dragging of the macula in ROP.
No treatment is required for pseudoexotropia. Parents can be reassured that their child most likely will outgrow the condition. Infants should be observed and reevaluated every 6 months
It is classified as primary infantile exotropia, where patients are healthy with no evidence of systemic or ocular disease
Parents and other persons who have regular contact with the patient usually reliably see the exodeviation because of the large degree of deviation: it almost always exceeds 30 prism diopters (pd), and may be a large as 90pd
Those who improve with occlusion therapy of the dominant eye are more likely to have early onset intermittent exotropia than true infantile exotropia
Botulinum toxin injection to the lateral rectus (LR) muscle, typically 2.5-5.0 units to both lateral rectus muscles, can be offered as an alternative to surgery. This technique minimizes secondary vertical deviation and ptosis that sometimes accompany higher doses or unilateral injections.18 The experience with botulinum is obtained mostly from the more common intermittent exotropia, and is fraught with recurrence.19 There are few studies of infantile exotropia treated with botox. Fewer than 50% of patients with constant exotropia responded to botulinum toxin injection of one LR muscle.20
To differentiate between true and pseudo:
Do monocular occlusion for 45 min. if near PD did not change. It is true DXT.
If near PBCT gets higher (difference between N and D >10PD) it is pseudo DXT
After the patch test with eyes being still dissociated, the measurements are repeated for near with a +3D add
Add bilateral +3.00 lens. If near PD gets higher about 20PD after +3 then it is true with high AC/A ratio.
If near PD didn’t change, it is true with normal AC/A ratio
Refractive error: overcorrecting minus lens, This is based on the principle of stimulating accommodative convergence and thus reducing an exodeviation. Full correction.
Orthoptics: These may be used to improve the control of the deviation. The aim is to make the patient aware of the manifest deviation
Part-time occlusion of the non-deviating eye may improve control in some patients. Alternate patching if no visual preference
Base in prisms
Unilateral lateral rectus recession and medial rectus resection are generally preferred except in true distance exotropia when bilateral lateral rectus recessions are more usual
Refractive error correction – Cycloplegic refraction should be done to assess any underlying myopia, hyperopia, astigmatism, or anisometropia. If refractive errors are not rectified, they can impair fusion and thus lead to a manifest deviation. Minus lenses, in particular, helps in regaining the fusion control. These patients need to be followed up closely at a gap of 3 months to check compliance and improvement in control after spectacle usage.
Over minus therapy – Minus lenses work by stimulating the accommodative convergence. This is particularly useful in patients with a high AC/A ratio.[21]
Antisuppression exercises – In the form of part-time occlusion, are particularly beneficial for very young children who cannot perform active orthoptic exercises. This may help in improving the stage of intermittent exotropia to exophoria. Occlusion can be advised for either the dominant eye or an alternate eye occlusion in patients with alternating exotropia t prevent amblyopia. These passive antisupression exercises are also helpful during waiting periods before surgical correction or in young children until accurate measurements are recorded.
Prismotherapy – Prisms have a limited role in patients with intermittent exotropia. These are used to promote fusional convergence. Base in prisms are used to promote bifoveal stimulation. Prims might also be useful in the immediate postoperative period as a temporary measure if patients complaint of transient disturbing diplopia.[22]
Orthoptics – Active anti-suppression exercises and diplopia awareness exercises like bar reading, cheiroscope, or synaptophore help make the patient aware whenever the deviation becomes manifest.[23] This helps in promoting the fusional convergence amplitudes. The aim is to obtain a near-normal point of convergence.
Surgical intervention might be needed when the exodeviation occurs for more than 50% of the waking hours, and there is a recorded gradual loss of fusional control, progressive increase of primary deviation, asthenopic symptoms not relieved by convergence, or fusional exercises, development of suppression or gradual deterioration of distance stereopsis.
This often results from poor visual acuity in one eye. Sensory exotropia is more common when unilateral vision loss occurs in infancy or adulthood. It may appear secondary to anisometropia, unilateral medial opacity secondary to corneal opacity or lenticular changes, unilateral aphakia, optic atrophy, or macular pathology.
A minority of patients develop intractable diplopia due to loss of fusion, even when good visual acuity is restored to both eyes and the eyes are realigned
Consecutive exotropia may result from a surgical overcorrection of esotropia or a spontaneous change of esotropia to exotropia
Incomitant exotropia is divided into paralytic (third nerve paralysis, isolated medial rectus paralysis, paralysis of convergence), A, V, or X pattern, or restrictive (Duane retraction syndrome, thyroid myopathy, restriction due to trauma or following surgery).