Causes and risk factors
Dislocation of lens can be a congenital anomaly. It can occur following trauma such as sports injury, severe blow to the eye or head injury or accidents. It can result from a systemic disease or ocular disease. It can occur as a result of a major eye surgery. Weakness of ligaments that support the lens [zonules] can also cause lens dislocation. Excessive stretching of zonules, degeneration of zonules, and tear of zonules can lead to dislocation of lens.
Clinical presentation
Patient presents with monocular diplopia [double vision in one eye]. There is dimness of vision for distant and nearer objects. Loss of accommodation is experienced. Signs like deep anterior chamber, jet black pupil are seen. There can be vibration or tremulousness of iris on movement of the eye [iridodonesis] or lens [phacodonesis]. Secondary glaucoma may be present in some cases. Uveitis may also be present. Photophobia, eye pain, headache may be accompanied symptoms. When lens is displaced in anterior chamber, it appears as an ‘oil globule.’ In posterior dislocation, lens can be seen lying at the bottom of vitreous cavity after dilatation of pupil.
Investigation
Medical history by the patient and clinical examination by the ophthalmologist helps in diagnosis. Routine ophthalmic examination is done. Visual field testing is recommended. Measurement of visual acuity is done.
Treatment
In anterior dislocation, immediate intracapsular extraction of lens and vitrectomy with or without implantation of anterior chamber IOL. In posterior dislocation, with no inflammatory signs, glasses to treat aphakia are prescribed. In complicated cases, extraction of lens and vitrectomy with implantation of anterior chamber IOL is carried out. Scleral fixation posterior chamber IOL [ SF PC IOL] can be done by experts. In addition to this, steroid eye drops, eye patch will contribute further to the treatment.
