1. The Hong Kong Polytechnic University,
Management of achromatopsia. Prescribe or not: A case report
Presented by
K.M. Law,
School of Optometry,
The Hong Kong Polytechnic University,
Hong Kong, China

2. Background
Achromatopsia is a congenital, inherited visual disorder in which cone function is either absent or reduced.

3. Clinical characteristics of achromatopsia
Reduce VA
Photophobia
Significant refractive error
Reduce or complete loss of colour discrimination

4. Case history
A 34-year-old accountant diagnosed of achromatopsia since childhood.
Subjective refraction
OD: DS (VA: 10/100-)
OS: / X 180 (VA: 10/100-)
Abnormal colour vision
Reduced contrast sensitivity
Corning 527X filter was used to reduce light sensitivity currently

5. Fundus OD OS

6. Contact lens fitting OD (Flexcon Red Prosthetic) Fig. 3
OS (Opulens 42C)
Fig. 4
BC / Dia /
Power
8.80 / 14.5 /
-11.50
8.90 / 14.5 /
/ x 180
Coverage / Centration
Full / Centre
Rotation
N/A
No rotation
Fitting
Acceptable VA
10 / 80+
10 / 80
Remarks: No significant improvement in colour vision , contrast sensitivity and VA but with increased visual comfort with red lens.

7. OD with prosthetic red lens
Contact lenses
OD with prosthetic red lens
OS with clear lens

8. Discussions
Photophobia is a common complain of people suffered from achromatopsia.
Symptoms of photophobia in patients with achromatopsia may be relieved due to attenuate light reaching the retina with the use of tinted contact lens.
Tinted contact lens may provide better visual comfort than tinted spectacle as it could limit periphery glare, eliminate back surface reflections and align visual axis better than spectacles.1

9. Conclusions
Tinted contact lenses should be considered if patient found significant improvement in visual comfort even though the improvement of visual acuity was minimal clinically.
Tinted zone of contact lenses should cover and well beyond the pupil margin under dim and bright conditions.
Extra care should be needed to minimize contact lens complications.

10. Reference
Red contact lenses for alleviation of photophobia in patients with cone disorders. Park WL. Sunness JS. American Journal of Ophthalmology. 137(4):774-5, 2004 Apr.