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Updated: Jun 26, 2026
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Intravital Video Microscopy Measurements of Retinal Blood Flow in Mice
Published on: December 26, 2013
[Tibolone's effect on retinal and ophthalmic arteries flowmetry]
Marco Aurélio Martins de Souza1, Selmo Geber
1Universidade Estadual de Montes Claros, Montes Claros, MG, Brazil. marcoams@uai.com.br
Summary
Tibolone, a menopausal hormone therapy, did not alter Doppler velocimetry parameters in ophthalmic and retinal arteries. This study found no significant changes in resistance index or pulsatility index in women using tibolone compared to placebo.
Area of Science:
- Ophthalmology
- Endocrinology
- Vascular Medicine
Context:
- Menopausal hormone therapy (MHT) is widely used for symptom management.
- Tibolone is a synthetic steroid with tissue-specific estrogenic, androgenic, and progestogenic effects.
- Ocular vascular health is a concern during menopause.
Purpose:
- To investigate the impact of tibolone on Doppler velocimetric parameters of ophthalmic and retinal arteries.
- To assess changes in resistance index (RI), pulsatility index (PI), and systole/diastole ratio (S/D) before and after tibolone administration.
Summary:
- A randomized, placebo-controlled, triple-blind study involving 100 menopausal women (50 tibolone, 50 placebo) was conducted.
- Doppler velocimetry of ophthalmic and retinal arteries was performed before and 84 days after treatment.
- No significant differences in RI, PI, or S/D were observed between the tibolone and placebo groups in either artery.
Impact:
- The findings suggest that a 2.5 mg dose of tibolone does not adversely affect ocular hemodynamics in menopausal women.
- This research contributes to understanding the vascular safety profile of tibolone.
- Further studies may explore long-term effects or different tibolone dosages on ocular vasculature.
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