Strabismus may persist or arise even in adulthood, when the decision to operate becomes very delicate, having to weigh both the potential functional and psycho-social benefits
Strabismus is an extremely common visual defect in children, but it can also sometimes be present in adulthood, either as a residual of a childhood strabismus or due to ex-novo onset in adulthood. About 4-5% of the population is affected by strabismus.
Strabismus consists of a deviation of the ocular axescaused by various causes, which can manifest itself as a convergent deviation (exotropy), divergent (exotropy), vertical (hyper- or hypotropia) or torsional (cyclotropy).
Motor impairments frequently result in correlated sensory changes, leading to changes in binocular vision, resulting from normal cooperation between the two eyes, and/or to a reduction in the visual acuity of one or both eyes (amblyopia).
Some forms of strabismus resolve spontaneously and do not require any treatment, while others require glasses, and in many cases surgery is the only solution.
Childhood squinting
Untreated childhood strabismus can cause a severe visual deficit in the deviated eye and the failure to develop normal binocular vision. Often, as a first resort, the use of an eye patch (occluder) applied to the 'straight' eye is recommended in order to stimulate the deviated eye and prevent the development of amblyopia, commonly referred to as 'lazy eye'.
In most cases, the strabismic child does not show any signs of visual difficulties, nor does he or she behave differently from any other child, which may lead the parent to mistakenly postpone the first visit to the beginning of primary school.
Squinting in adults
Strabismus arising in adulthood may be a consequence of metabolic disorders, or secondary to neurological disorders, or be the result of trauma or more or less significant sensory deficits. Sometimes, ageing causes a change in the soft tissue around the eye, which is among the contributing causes of strabismus in the elderly.
This type of strabismus generally has an acute symptomatology, particularly in cases of misalignment that appear suddenly in adulthood, patients almost always complain of double vision.
In adults, it is possible to adopt some of the corrective therapeutic approaches used for children, such as the use of prismatic glasses, the practice of specific exercises to regain coordination of both eyes (functional exercises) and, as a last resort, resorting to surgery.
Frequently, strabismus surgery is part of a complementary therapeutic course, which includes correction with glasses of any other refractive defect, rehabilitation therapy of any amblyopia through occlusion, or other non-surgical therapies that complement each other and prepare the patient for the best post-surgical outcome.
Cosmetic or functional surgery?
Strabismus correction surgery is usually performed in an outpatient setting and is not particularly painful. However, a very sensitive issue is whether the decision to surgically correct strabismus in adults should be guided primarily by a functional purpose or can be taken for psychological and aesthetic reasons.
Suffering from strabismus leads to so-called 'psychosocial symptoms', which result in a lower quality of life than people without the condition. Strabismus patients have been found to be 10 times more likely to suffer from clinical anxiety or depression, 'sociophobia' (social anxiety disorder) and a tendency to avoid all social contact, difficulty making eye contact and interacting with other people by looking at them, embarrassment, self-esteem, difficulty establishing friendships and social relationships
While from a functional point of view, surgical realignment of the eyes in adults aims to improve double vision, depth perception and sometimes the field of peripheral vision, on an emotional, social and psychological level, eye realignment can help restore a normal facial appearance and ensure a better quality of life.
A systematic review of the scientific literature available between 1946 and 2023 was published in April 2024, Strabismus Surgery for Psychosocial Reasons-A Literature Reviewto evaluate the evidence for postoperative outcomes in adult patients, aged 18 years and older, who underwent strabismus surgery for psychosocial reasons. Sixty-nine studies were considered, with reference to heterogeneous cohorts of surgical patients with strabismus.
The results show that the majority of adults who underwent strabismus surgery for psychosocial reasons achieved significantly better postoperative eye alignment and a subsequent improvement in related quality of life. Positive results were noted as early as three months after surgery. Other positive outcomes such as enlargement of the visual field, improvement of near and binocular vision, better performance in the movement of both eyes and in the performance of daily activities have been reported but not systematically investigated. Furthermore, it would be necessary to promote a consensus as to which objective parameters should be used to measure the postoperative success of strabismus surgery, especially if it is decided for psycho-social reasons.
Complications
The most common risks of complications of strabismus surgery are residual misalignment of the eyes and diplopia. Most diplopia after strabismus surgery is temporary. Persistent residual double vision is possible, which is corrected by the use of prisms. Fortunately, the most serious risks are rare and include complications of anaesthesia, scarring in the white part of the sclera, infection, eyelid numbness, bleeding, retinal detachment and reduced visual acuity.
In most cases, patients return to normal daily activities within a few days, while swimming and heavy physical activities should be avoided, at least for a few weeks after surgery.
On the subject of strabismus, see also:
- A frequent visual defect: strabismus - Oculista Italiano
- Strabismus heredity - Italian Ophthalmologist
- Arblaster G, Buckley D, Barnes S, Davis H. Strabismus Surgery for Psychosocial Reasons-A Literature Review. Br Ir Orthopt J. 2024 Apr 22;20(1):107-132. doi: 10.22599/bioj.352. PMID: 38681188; PMCID: PMC11049605.
- Beauchamp, GR, Black, BC, Coats, DK, Enzenauer, RW, Hutchinson, AK, Saunders, RA, ... Felius, J. 2003. The management of strabismus in adults-I. Clinical characteristics and treatment. J AAPOS, 7(4): 233-240. DOI: 10.1016/S1091-8531(03)00112-5
- Estes, KJ, Parrish, RK, Sinacore, J, Mumby, PB and McDonnell, JF. 2020. Effects of corrective strabismus surgery on social anxiety and self-consciousness in adults. J AAPOS, 24(5): 280.e281-280.e284. DOI: 10.1016/j.jaapos.2020.05.017
- Serafino, M, Granet, DB, Kushner, BJ, Dagi, LR, Kekunnaya, R and Nucci, P. 2019. Use of the Delphi process for defining successful outcomes for strabismus surgery. J AAPOS, 23(6): 309-312. DOI: 10.1016/j.jaapos.2019.07.006