Retinal Temperature Determination Based on Photopic Porcine Electroretinogram.

Objective: Subthreshold retinal laser therapy (SLT) is a treatment modality where the temperature of the retinal pigment epithelium (RPE) is briefly elevated to trigger the therapeutic benefits of sublethal heat shock. However, the temperature elevation induced by a laser exposure varies between patients due to individual differences in RPE pigmentation and choroidal perfusion. This study describes an electroretinography (ERG)-based method for controlling the temperature elevation during SLT.

Induction of Heat Shock Protein 70 in Mouse RPE as an In Vivo Model of Transpupillary Thermal Stimulation.

The induction of heat shock response in the macula has been proposed as a useful therapeutic strategy for retinal neurodegenerative diseases by promoting proteostasis and enhancing protective chaperone mechanisms. We applied transpupillary 1064 nm long-duration laser heating to the mouse (C57Bl/6J) fundus to examine the heat shock response in vivo. The intensity and spatial distribution of heat shock protein (HSP) 70 expression along with the concomitant probability for damage were measured 24 h after laser irradiation in the mouse retinal pigment epithelium (RPE) as a function of laser power.

In vivo monitoring of mouse retinal temperature by ERG photoresponses.

Non-damaging heating of the retina and RPE provides a promising treatment for retinal diseases. However, the lack of proper control over the temperature hinders the development of safe and repeatable procedures. Here, we demonstrate with mice a non-invasive method for estimating the temperature changes in the retina and the RPE during a heating procedure.

A Novel Method for Mouse Retinal Temperature Determination Based on ERG Photoresponses.

This study introduces a novel retinal temperature determination method based on the temperature dependent properties of photoresponses recorded by electroretinography (ERG). The kinetics and amplitudes of ERG photoresponses depend on retinal temperature. Additionally, raising retinal temperature increases the probability of long-wavelength photon absorption, which manifests as temperature dependence of photoreceptor sensitivity.