ahp Flashcards
what is a normal head posture
When the body is erect and facing forwards
The median plane of the head is continuous with the median plane of the body
what is an ahp
Compensatory head posture’
Consist of:
Head turn to R or L (Face turn)
Chin elevation or depression (Head up/ Head down)
Head tilt to R or L shoulder
May exist singly or combined
Torticollis: AHP includes a head tilt
what are non ocular causes of ahps
Congenital
Contracture of sternocleidomastoid muscle in neck
Head tilt to affected side
Head turn to unaffected side
May adopt chin elevation (head up)
Acquired
Deafness - unilateral/ asymmetrical
Head turn to more affected side
Shyness
Often chin depression (Head down) and variable
Mental retardation
Often variable AHP
Habit
Neurological – brain tumour
Arthritis / rheumatism
Disorders/ injuries of spine
what are ocular causes of ahp
Obtain/ maintain BSV
Incomitant strabismus
A & V patterns
Separate diplopic images further
Insuperable diplopia
Gain foveal fixation
Infantile esotropia
Gross limitation preventing foveal fixation in PP
Optimise VA
Refractive errors
Nystagmus
DVD
Head tilt towards fixing eye appears to ↓ DVD
Centralise field of vision
Bilateral ptosis
Gaze palsies
Homonymous hemianopia
Avoid pain
Graves Ophthalmopathy
Blow-out #
what is the diagnostic value of ahp
Diagnostic
Aids in diagnosis of affected EOM in palsies
Aids in differential diagnosis of longstanding versus recently acquired palsies
Degree of AHP < in longstanding palsies
Patient less aware of AHP in longstanding
Presence of pre-existing BSV
how to assess ahp
Ensure patient sitting / standing straight
Observe patient on same level, directly in front
Note any facial asymmetry
Assess if one ear more visible than other
Check eyes are level
Observe chin position from side
Straighten head and allow patient to resume “normal” position
Observe AHP for 1/3m, 6m, when performing visual task
Old photos may identify duration of AHP
Ask patient if aware of AHP
how to differentially diagnose ahp
straightening head is difficult/ impossible for someone who has congenital non ocular
for ocular congenital straightening head is easy
congenital non ocular aware of ahp - may be
ocular - unaware - longtstanding - aware and without tech ache -acquired
congenital - non ocular - usually asymptomatic
congenital ocular may be symptomatic
congential non ocular have bsv without and without ahp
ocular bsv with ahp without ahp diplopia / suppress
ct congential non ocular nad
ocular congential- presence of strabismus / nystagmus
om are full in congenital non ocular in ocular muscle imbalance
hess is normal in congenital non ocular in ocular there is a muscle imbalance
how to differentially diagnose a ahp between congenital non ocular and ocular
when you occlude one eye of congenital non ocular they have non change in app
with ocular - head straightens on occlusion of paretic eye
ui ocular va testing -no change of ahp in congenital non ocular
ocular may change to improve va if presence of nystagmus
medical congenital ntial non ocular ppl have indications for reasons for adopting ahp example deafness aqs a pose to those with ocular problems that may be with illness relevant to muscle imbalance
how to record ahp
Define
Small, moderate, marked
Variable or alternating
Distance(s) AHP noted
Present with and without optical correction
how to manage ahp if asymptomatic
Asymptomatic
Small
relieve diplopia and/or pain
No active treatment
how to manage ahp if symptomatic
Symptomatic
Small-moderate AHP
Relieve using prisms, occlusion
Botulinum toxin injection
Surgery
how to manage ahp if they are symptomatic and have a marked ahp
Symptomatic
Marked AHP
Indication for surgery
Neurogenic palsies
Mechanical palsies
Nystagmus
Young children- prevent secondary contractural neck changes
Affect amount of surgery
Consider under-correct if longstanding
what are reasons for a head turn
Purpose
Move eyes away from field of action of paresed muscle
Move eyes to a position where deviation is least
Enable eye to fixate centrally – gross limitation
Permit the use of the nose as an occluder
Utilisation of VOR
Head turn L eyes move R
Paralytic strabismus:
Head turned in direction of paresed muscle
if someone has a right left palsy where will there head turn be
In right lateral rectus palsy, the affected eye will have difficulty moving outward towards the right side. To compensate for this, the person may adopt a head posture where they turn their head to the right to align their eyes and maintain binocular vision. This is known as a compensatory head turn. The head turn is usually towards the side of the affected eye, so in this case, the person would likely turn their head to the right.
if someone has a left superior rectus palsy where will there head turn be
Head turn left