Sir,

Myopia after blunt ocular trauma is usually transient, resolving within weeks of the injury, and may be caused by ciliochoroidal oedema and thickening of the crystalline lens.1 This condition is distinct from bilateral accommodative spasm occurring after closed head injury, which may involve one or more elements of the near synkinesis and has variable periods of recovery.2, 3 Here, we report a case of unilateral traumatic myopia that had not resolved 3 months after blunt ocular injury.

Case report

A 28-year-old woman had been struck in the left eye by hard, baseball-sized ball and presented with ocular pain and reduced vision. Her unaided acuities were 20/20 OD and counting fingers OS, but the injured eye improved to 20/30 with a −6.50 sph/−0.50 cyl × 90°. Cycloplegic retinoscopy and refraction revealed 20/30 vision OS with a plano/−0.50 cyl × 90° correction. The pupils were equal and reactive to light and accommodation. The anterior segments were clinically normal. The intraocular pressures were 10 mmHg OD and 12 mmHg OS, and the fundi were normal. Axial length was 24.18 mm in the right eye and 24.05 mm in the left. The anterior chamber depth was 2.85 and 2.94 mm and lens thickness was 3.68 and 4.60 mm in the right and left eyes, respectively.

After 3 months, the refractive findings were unchanged, and she was prescribed cyclopentolate 1% daily.

Discussion

Closed head trauma may cause bilateral accommodative spasm in young adults, which may be permanent.2 In addition, blunt ocular injury may cause a bilateral pseudo-myopia,4 which may be secondary to ciliary oedema and spasm.1 In our patient, the increased lens thickness was probably due to the induced accommodation. Given that the anterior chamber depth was greater in the injured eye, it is unlikely that the induced myopia was caused by anterior displacement of the lens iris diaphragm. To our knowledge, this form of traumatic myopia has not been previously reported to last more than several weeks. In this case, the pseudo-myopia was still present 3 months after the injury. Symptoms were relieved by cycloplegics.