[Treatment of fusional disorders in patients with brain damage]

Abstract

Background: We trained fusional convergence systematically using 3 orthoptic devices (fusion trainer, prisms, cheiroscope) in brain damaged patients with a severe deficit of convergent fusion.

Patients and methods: 12 patients were selected, 6 with vascular cerebral lesions and 6 with traumatic brain damage. The chronicity (time since lesion) was 15.8 months (range: 2-108). Near and far visual acuity, accommodation, convergent fusional range, stereopsis (Titmus and TNO test), maximal reading duration and subjective complaints (e.g. eye strain, headache) were evaluated. To separate improvements during treatment from spontaneous recovery of function or measurement artefacts we performed repeated measurements before treatment (baseline period) during a time span of 4-6 weeks. Follow-up measurements could be performed in 9 of 9 patients 10 months after cessation of treatment.

Results: No improvements were seen during the baseline period. 11 of 12 patients showed a significant recovery of fusional range during training which remained stable during the 10-month follow-up period. 10 of 11 patients showed significant improvements of local stereopsis (Titmus test) and 4 of 5 patients of global stereopsis (TNO test). All patients showed a significant increase of near visual acuity of about 10% (decimal visual acuity), improved reading ability and a reduction of subjective symptoms resulting from fusional deficiency, e.g. eye strain, headache.

Conclusions: These results suggest a considerable potential for recovery of oculomotor and visual functions in brain damaged patients after training.