Resume: A new study reveals that early changes in age-related macular degeneration (AMD) can lead to measurable local vision loss. Researchers used advanced imaging to discover that iRORA lesions, early signs of retinal damage, significantly reduce visual acuity.
This discovery could improve the monitoring and treatment of AMD, and potentially prevent serious vision loss. The findings offer hope for earlier intervention in this progressive eye disease.
Key Facts:
- Early detection: iRORA lesions in early AMD cause significant local visual loss.
- Advanced imaging: The high-resolution AOSLO method shows detailed retinal damage.
- Improved monitoring: Early detection can lead to better treatment and prevent serious vision loss.
Source: University of Bonn
New research from the University Hospital Bonn (UKB) in collaboration with the University of Bonn has shown for the first time that certain early changes in patients with age-related macular degeneration (AMD) can lead to measurable local vision loss.
This discovery could contribute to better treatment and monitoring of this eye disease in elderly patients, which otherwise slowly leads to central blindness. It could also help test new therapies.
AMD primarily affects older adults. If left untreated, the disease leads to progressive loss of central vision, which can significantly impede daily activities such as reading or driving. Researchers around the world are intensively searching for ways to improve early detection and treatment of this disease before major losses occur.
A research team from the UKB Eye Clinic, in collaboration with the University of Bonn and in close cooperation with basic and clinical scientists, specifically examined patients with early forms of AMD. The researchers focused on the so-called iRORA lesions, which are very early anatomical signs of damage to the retina.
The results will be published in BMJ Open Ophthalmology.
“We used the microperimetry method to precisely measure visual acuity in these affected areas of the retina,” explain Julius Ameln, Dr. Marlene Saßmannshausen and Dr. Leon von der Emde, who conducted the studies.
This measures the sensitivity of the retina to light stimuli to identify visual impairment. Because the affected retinal areas are smaller than 250 micrometers, routine clinical devices reach their limits.
A high-resolution research instrument developed in Bonn, the so-called adaptive optical scanning light ophthalmoscope (AOSLO), offers a solution.
“It enables imaging of the retina with microscopic resolution and allows functional testing of small areas down to individual photoreceptors,” says Dr. Wolf Harmening, head of the AOSLO laboratory at the UKB Eye Hospital and member of the Transdisciplinary Research Area (TRA) “Life & Health” at the University of Bonn.
The results were clear: visual acuity in the lesion areas was clearly reduced. With the standard method, the loss was on average 7 units compared to a control area. With the precise AOSLO method, the loss was 20, which corresponds to a reduction in light sensitivity by a factor of 100.
These results illustrate that iRORA lesions already have a significant impact on vision. This early retinal damage could serve as a marker to better monitor the progression of the disease and treat it at an early stage.
The results of this study represent a next step in better understanding how late-stage dry AMD develops and causes extensive damage to the retina.
“Our research shows that even these early lesions can contribute to a very local, but nevertheless significant, deterioration of vision in our patients,” explains Dr. Wolf Harmening.
“This makes them a potential marker that could help to better monitor the progression of AMD and treat it at an earlier stage,” adds Prof. Dr. Frank Holz, Director of the UKB Eye Clinic.
About this visual neuroscience research news
Author: Inka Väth
Source: University of Bonn
Contact: Inka Väth – University of Bonn
Image: The image is attributed to Neuroscience News
Original research: Open access.
“Assessment of local sensitivity in incomplete retinal pigment epithelium and outer retinal atrophy (iRORA) lesions in intermediate age-related macular degeneration (iAMD)” by Julius Ameln et al. BMJ Open Ophthalmology
Abstract
Assessment of local sensitivity in incomplete retinal pigment epithelium and outer retinal atrophy (iRORA) lesions in intermediate age-related macular degeneration (iAMD)
Lesions of incomplete retinal pigment epithelium and outer retinal atrophy (iRORA) are associated with disease progression in age-related macular degeneration. However, the corresponding functional impact of these precursor lesions is unknown.
We present a cross-sectional study of four patients using clinical MAIA (stimulus size: 0.43°, ~125 µm) and adaptive optics scanning light ophthalmoscope (AOSLO, stimulus size 0.07°, ~20 µm) based microperimetry (MP) to assess the specific impact of iRORA lesions on retinal sensitivity.
AOSLO imaging showed an overall decreased reflectivity of the photoreceptors and patches of hyporeflective regions in drusen with scattered hyperreflective foci in iRORA regions. MAIA-MP yielded a mean loss of retinal sensitivity of -7.3±3.1 dB in iRORA lesions compared to the in-eye control. With AOSLO-MP, the corresponding loss of sensitivity was 20.1±4.8 dB.
We have shown that iRORA lesions are associated with a severe reduction in retinal sensitivity. Larger cohort studies are needed to validate our findings.