Retinal specific measurement of dark-adapted visual function: validation of a modified microperimeter.
BMC Ophthalmol
; 11: 5, 2011 Feb 08.
Article
em En
| MEDLINE
| ID: mdl-21303544
ABSTRACT
BACKGROUND:
Scotopic function is an important marker of many retinal diseases and is increasingly used as an outcome measure in clinical trials, such as those investigating gene therapy for Lebers congenital amaurosis. Scotopic visual function has traditionally been measured using an adapted perimetry system such as the Humphrey field analyser (HFA). However this system does not control for fixation errors or poor fixation stability. Here we evaluate the use of an adapted microperimeter to measure visual function at defined retinal regions under scotopic conditions.METHODS:
A MP-1 microperimeter (Nidek Technologies, Italy) was modified by adding a 1 log unit Neutral Density filter and a 530 nm shortpass filter within the optical path of the instrument. Stray light was shielded. Fine matrix mapping perimetry was performed on five younger (< 35 years) and five older (> 65 years) subjects with no eye disease and good vision. All subjects were fully dark adapted before testing and pupils were dilated with 1% tropicamide. Tests was performed once on the modified MP-1 microperimeter and once using a modified HFA, in a counterbalanced order.RESULTS:
A foveal scotopic scotoma with a sensitivity reduction of >1 log unit was found using each instrument. In addition, the MP-1 system showed the retinal location of the foveal scotoma. Mean test time was 25 minutes for the MP-1 and 32 minutes for the HFA.DISCUSSION:
A modified MP-1 microperimeter can be used to measure scotopic retinal function, creating results which are comparable to the modified Humphrey field analyser. Advantages of the MP-1 system include the ability to track the retina through testing, retinal localisation of the scotoma and a faster test time.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Visão Ocular
/
Adaptação à Escuridão
/
Testes de Campo Visual
Tipo de estudo:
Diagnostic_studies
Limite:
Adult
/
Aged
/
Humans
Idioma:
En
Revista:
BMC Ophthalmol
Assunto da revista:
OFTALMOLOGIA
Ano de publicação:
2011
Tipo de documento:
Article
País de afiliação:
Reino Unido