Retinal Microvascular Density and Perfusion during an Insulin-Induced Hypoglycemia Episode: A Warning Call
Gerardo González-Saldivar1,2, José Gerardo González-González2,3, David Robert Chow4
1Department of Ophthalmology, Facultad de Medicina y Hospital Universitario "Dr. Jose E. González", Universidad Autónoma de Nuevo León, Av. Madero y Gonzalitos s/n, Colonia Mitras Centro, Monterrey, Nuevo Leon 64460, Mexico.
International Journal of Clinical Practice
|October 25, 2023
Summary
Acute hypoglycemia significantly impacts retinal vascularity in diabetes patients. This suggests repeated low blood sugar episodes may worsen diabetic retinopathy over time.
Area of Science:
- Ophthalmology
- Endocrinology
- Medical Imaging
Background:
- Diabetes mellitus (DM) is a systemic disease with significant ocular complications.
- Diabetic retinopathy (DR) is a leading cause of vision loss in diabetic patients.
- The impact of acute hypoglycemia on retinal vascularity is not fully understood.
Purpose of the Study:
- To evaluate changes in retinal vascular perfusion and density using optical coherence tomography angiography (OCTA).
- To assess these changes before, during, and after hypoglycemia in individuals with diabetes mellitus (DM).
- To compare findings in individuals with and without diabetic retinopathy (DR).
Main Methods:
- Participants underwent ophthalmological examination and OCTA at baseline, during hypoglycemia, and upon glucose normalization.
- Macular thickness, vascular perfusion, and density were measured using OCTA.
- Retinal vascular reactivity was analyzed by assessing superficial plexus vascular perfusion and density.
Main Results:
- A statistically significant difference in baseline vascular perfusion and density was observed between control and DM groups.
- Vascular perfusion and density were significantly reduced in all groups during hypoglycemia.
- An exception was noted in vascular density in DR cases, which did not significantly decrease.
Conclusions:
- Acute hypoglycemia significantly alters retinal vascularity in patients with DM, irrespective of DR status.
- Repeated episodes of acute hypoglycemia may contribute to the long-term exacerbation of diabetic retinopathy.
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