Return to Diagnosis ListShow Learning Points most relevant to Phase 1:

Infant or child with strabismus

Clinical Discipline(s)/Organ System(s)
Ophthalmology, Paediatrics
Progress Test Topic(s)
Eyes
Description
A 3 year old Māori boy presents with a 4-6 week history of the eyes turning in ('cross-eyed') intermittently, but becoming more frequent. The parents note this is particularly obvious when the child is looking at near objects, or is tired. On examination the child's vision measures 6/36 in the right eye and 6/12 in the left eye with Kay pictures. The right corneal reflex is seen at the lateral iris margin. On cover test of the right eye the left eye holds in fixation. On occlusion of the left eye, the child is quite happy and the right eye moves out to take up fixation. The red reflex is normal and dilated examination shows clear ocular media and healthy looking optic nerves and retinas. Cycloplegic refraction shows hypermetropia of +8 dioptres for each eye. 
Progress Test-Type Questions:   Question 1 | Question 2
Applied Science for Medicine 
   - Anatomy and function of the extraocular muscles
   - Describe the near and accommodative reflex, with reference to accommodative esotropia
   - Normal visual development and maturation in infants
   - Optics of hypermetropia and defocus, and spectacle correction
   - Explain common terminology (phoria, tropia, exo, eso, ortho), underlying causes of, and treatment for strabismus
   - Describe the visual pathways, neurological development, pathology and treatment of amblyopia
Clinical and Communication Skills 
   - Elicit a relevant history of visual development and behaviour, including eye movements, onset of strabismus, including which eye, which direction, and time and duration of strabismus
   - Elicit pregnancy, neonatal and family histories with relevance to risk factors for strabismus
   - Perform a focused examination of visual behaviour in a child, visual acuity, eye movements, cover test, cover uncover test, and red reflex, particularly focusing on the signs of direction of strabismus, preferential fixation, correction with glasses, epicanthal folds
   - Clear description of the problem to child and family/whānau, to aid in adherence for glasses wearing; describe need to prevent and treat amblyopia, possibility of surgery
Personal and Professional Skills 
   - Team work: interaction with optometrists and orthoptists
   - Clinical reasoning: Consider differential diagnosis, other causes for strabismus, binocularity
Hauora Māori 
   - Ensure equal access to resources, including awareness of spectacle subsidies
Population Health 
   - Provision of preschool vision screening including well child, Plunket, and B4 school screening to detect children with vision and ocular abnormalities
Conditions to be considered relating to this scenario
Common
accommodative esotropia, leukocoria (must have red reflex to exclude retinoblastoma), congenital esotropia (non-accomodative, requiring surgical correction), extraocular muscle palsy associated with post-viral or posterior fossa compressive lesion, pseudostrabismus
Uncommon
sensory strabismus (congenital cataract or other intraocular lesion), Duane syndrome