Abnormal Head Posture due to Ocular Problems- A Review

摘要

An abnormal head posture (AHP), or torticollis, is a common condition in children, with an estimated incidence of 1.3%. This condition is encountered commonly by primary care family pediatricians. AHP can be congenital or acquired. The cause of the AHP can be ocular, orthopedic and neurologic. The orthopedic causes of AHP include congenital muscular torticollis due to tightness of the sternocleidomastoid muscle, Klippel- Feil anomaly and brachial plexus injury.nnNeurologic causes of AHP are mainly related to brain tumors, postinflammatory central nervous system conditions, psychomotor delay and focal dystonia. Other less common reasons for AHP are: Sandifer syndrome (hiatal hernia associated with gastro- esophageal reflux) and unilateral hearing loss.nnNumerous ocular conditions can cause AHP or “ocular torticollis”. Among them: superior oblique muscle palsy, lateral rectus muscle palsy, nystagmus, vertically incomitant horizontal strabismus (A or V patterns), Brown's syndrome, Duane's syndrome, refractive errors and DVD.nnThe AHP can take the form of head tilt, face turn, chin up, chin down or combined, depending on the specific etiology. However, there are many variations and the type of the head posture cannot reliably predict the underlying cause.nnSince the etiology is not always obvious, these patients must be carefully evaluated, and sometimes a multidisciplinary approach is needed, including examinations by ophthalmologist, neurologist and orthopedist.nnOcular AHP is usually an attempt to improve visual acuity or binocularity. Some patients adopt the head posture to avoid diplopia caused by incomitant strabismus, those with nystagmus adopt a head position that brings the eyes to the null point (where the oscillations dampen or markedly diminish). Ocular AHP is usually a binocular phenomenon. Rarely, abnormal head position can be acquired following visual loss in one eye.nnThe majority of these ocular conditions require eye muscle surgery. Different ocular etiologies of AHP require different surgical strategy, for this reason careful etiological diagnosis is important.nnThe purpose of this article is to review the ocular conditions that cause AHP, their relative frequency, indication for surgery and the appropriate surgical treatment.