Our study evaluated the blood flow rates of retrobulbar vascular structures
and elasticity of the eye in MVP patients. The results indicated that MVP patients had higher ROF/S values compared with the healthy participants. In the comparison of the MVP patients with a control group, statistically significant differences were found in the EDV, and PSV values of the PCA and CRA. A significant relationship was releated with ocular elasticity. MVP may occur as a result of various pathological mechanisms involving any of the functional components of the mitral valve apparatus. Primary MVP, which is seen as a result of valvular collagen disruption and myxomatous infiltration, is the prominent condition among them. MVP may be familial, sporadic, non-syndromic, or part of a well-defined syndrome of heritable connective tissue disorders, such as Marfan syndrome, Ehlers-Danlos syndrome, polycystic kidney disease among others.
Patients with primary MVP have excessive connective tissue, which causes thickening of the spongiosa layer due to the excess of dermatan sulfate, which is a glycosaminoglycan. This condition weakens the structure of the mitral leaflets and adjacent tissues, resulting in elongation of the chordae tendineae.
Ocular involvement can potentially lead to vision threatening disease. MVP can be associated with ophthalmological diseases such as keratoconus (KC), glaucoma, chronic progressive external ophthalmoplegia, and retinal artery embolism.
According to the literature information some studies showing a relationship between MVP and ocular involvement. Duru et al. reported thinning of Bowman layer in the inferior half of the cornea in patients with MVP.Lichter et al. found 22.2% keratoconus patients with MVP. Akcay et al. reported that KC prevalence is higher than control individuals in MVP patients and the biomechanical properties of the cornea are altered in patients with MVP.
Chiang SJ et al. reported that MVP is a significant predictor for the development of Open angle glaucoma, after adjusting for possible confounding factors. In MVP, the disease duration induces scleral tissue alterations which can lead to scleral destruction. Thus can be related with ocular involvement in MVP disease.
Previous studies have demonstrated the elastographic characteristics of ocular tissue
Ünal et al. investaged the optic nerve head (ONH) characteristics in patients with primary open angle glaucoma (POAG) using real-time elastography. They found that human scleral rigidity of POAG patients was greater than the control eyes. Agladioglu et al. reported the correlation between primary open angle glaucoma and ocular elasticity in adults and demonstrated that anterior vitreous/posterior vitreous strain ratio increases in glaucoma patients. Kazemi et al. found that ocular rigidity was significantly lower in glaucomatous eyes than control eyes.
In addition to these associated with ophthalmological diseases, involvement of retinal vasculer manifestations retinal embolizm and retinal vascular occlusive disorders.
Previous studies have reported abnormal elastic properties of the vascular systems in MVP. Kardesoglu et al. found that the aortic stiffness index was increased. Erolu et al. reported that increased elasticty of the aorta in childhood.
To the best of our knowledge, our study is the first to compare the blood flow rates of retrobulbar vascular structures and elasticity of the eye at the same time in MVP patients. This study demonstrated that MVP patients has a statistically significant difference scleral elasticity. The mean ROF/S values were significantly increased in patients with MVP as compared to the control group. The results of this study showed a significant difference between the control, and MVP groups in respect of the EDV and PSV values of PCA, and CRA. From these results, it can be said that vascular extracellular matrix changing in the vessels feeding the eye. This histological alteration can cause the feeding of tissues will be impaired with a reduced flow and consequently more ocular complications will be seen such as retinal vascular occlusive disorders. Nevertheless, there is a need for further studies to evaluate the importance of early determination of ocular vascular damage in MVP with CDI and RTE.