Abstract
Purpose: :
Dopamine beta-hydroxylase (DBH) deficiency is a rare type of autonomic failure caused by a disturbance in the normal synthesis of the enzyme that converts dopamine to norepinephrine. Previous reports have described ptosis and miosis in patients with DBH deficiency, but the spectrum of ophthalmologic findings in this disease is not well characterized. We report the ophthalmic findings in three patients with DBH deficiency and assess them in the context of other reports in an attempt to discern if a screening protocol for this disorder would benefit from the inclusion of ophthalmic criteria.
Methods: :
A complete ophthalmic examination was completed on three patients with DBH deficiency who were being followed in the inpatient clinical research unit at our institution. Specific ophthalmic findings studied included intraocular pressure (IOP) in various positions, eyelid and pupillary measurements and the response of the latter two to sympathomimetic drops.
Results: :
The mean age of the three patients was 19.7 ± 3.06 years. Two patients were male and one was female. The two males were siblings. The mean age at diagnosis was 18.7 ± 3.79 years, though all patients had symptom onset in early childhood. Mean IOP (in mm Hg) in these patients while standing, sitting and supine was 7.67 ± 2.25, 15.0 ± 3.58 and 15.8 ± 0.98, respectively. Mean palpebral fissure (PF), levator function, and margin-reflex distance (in mm) were 8.17 ± 0.98, 16.0 ± 0 and 2.75 ± 0.61, respectively. The mean PF increased to 9.50 mm ± 0.55 with instillation of 2.5% phenylephrine drops. Significant miosis and papillary supersensitvity to 2.5% phenylephrine were not observed.
Conclusions: :
The ophthalmologic findings of the three patients in this case series are not striking as might be expected given the complete lack of intrinsic sympathetic function. The eyelid measurements are consistent with those seen with Horner’s syndrome, but the pupillary function and intraocular pressure changes noted do not seem markedly different from the overall population. Overall, this suggests that there is phenotypic variation in the ophthalmic findings of DBH deficient patients. A meticulous exam would be required to observe these findings in the context of a screening test for DBH deficiency.
Keywords: intraocular pressure • eyelid • pupil