doi:10.1111/jog.12673
J. Obstet. Gynaecol. Res. Vol. 41, No. 7: 1080–1086, July 2015
Ocular blood flow in polycystic ovary syndrome Nurgül Örnek1, Mikail I˙nal2, Özlem Banu Tulmaç3, Zeynep Özcan-Dag˘3 and Kemal Örnek1 Departments of 1Ophthalmology, 2Radiology and 3Gynecology and Obstetrics, Kırıkkale University School of Medicine, Kırıkkale, Turkey
Abstract Aim: The aim of this study was to evaluate whether the presence of polycystic ovary syndrome (PCOS) alters ocular blood flow parameters. Material and Methods: Color Doppler imaging of the orbital vessels was performed in 41 eyes of 41 patients with PCOS. Forty-eight eyes of 48 age-matched volunteers served as controls. The ophthalmic artery (OA), the central retinal artery and the posterior ciliary artery were examined. Ocular blood flow indices of the peak systolic velocity, diastolic velocity, end-diastolic velocity, systolic/diastolic ratio, resistive index and pulsatility index were computed. Results: The peak systolic velocity, diastolic velocity and end-diastolic velocity of the OA, central retinal artery and posterior ciliary artery were significantly increased in PCOS patients in comparison to the controls (all P < 0.001). The mean systolic/diastolic ratio, resistive index and pulsatility index of the OA in PCOS patients were significantly decreased (all P < 0.05). Ocular blood flow velocity was positively correlated with serum luteinizing hormone, follicle-stimulating hormone and total cholesterol levels. There was a significant negative correlation between serum glucose and insulin levels and ocular blood flow velocity. Conclusion: Ocular blood flow velocity is increased in PCOS patients and vascular resistance seems to decrease only in the OA. Key words: blood flow, ocular, polycystic ovary syndrome.
Introduction Polycystic ovary syndrome (PCOS) is the most common endocrine disorder affecting as many as 5–8% of women of reproductive age. Despite the various clinical and experimental data published, the pathogenesis of this syndrome remains unclear. It is characterized by the presence of polycystic ovary, oligoovulation, hyperandrogenism and/or hirsutism and the exclusion of the related disorders.1 Patients with PCOS seem to have a higher risk of insulin resistance, hyperinsulinemia, glucose intolerance, dyslipidemia, and an increased prothrombotic state, possibly resulting in a higher rate of diabetes mellitus, liver disease,
subclinical atherosclerosis, vascular dysfunction and finally cardiovascular disease and mortality.2–4 Previous reports have shown that suppression of androgen improves microvascular dilation via endothelin receptors and the nitric oxide system of the cutaneous microvascular system is impaired in patients with PCOS.2–4 Therefore, the vascular tone shifts towards vasoconstriction characterized by reduced vasorelaxation in the early phase of PCOS and these patients are at a greater risk of premature atherosclerosis.5 Moreover, a recent meta-analysis has found a two-fold risk of coronary heart disease and stroke for PCOS patients when compared to women without PCOS.6
Received: August 5 2014. Accepted: December 1 2014. Reprint request to: Dr Kemal Örnek, Kırıkkale Universitesi Tıp Fakültesi, Yahs¸ihan, Kırıkkale 71100, Turkey. Email:
[email protected]
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© 2015 The Authors Journal of Obstetrics and Gynaecology Research © 2015 Japan Society of Obstetrics and Gynecology
Ocular blood flow
Color Doppler imaging (CDI) of orbital vessels is a procedure that has been recently used for detecting various ocular disorders and is widely used for detecting and measuring blood flow velocities in the orbital vessels.7 Measurements of the flow velocity of the ophthalmic artery (OA), central retinal artery (CRA) and posterior ciliary artery (PCA) are possible using color Doppler ultrasonography.8 In the present study, we hypothesized that there may be alterations in the ocular blood flow (OBF) of patients with PCOS. To our knowledge, this is the first study evaluating OBF parameters in patients with PCOS.
Methods Forty-one PCOS patients and 48 healthy age-matched volunteers with regular menstrual cycle as a control group were enrolled into this study. PCOS was diagnosed according to the 2003 Rotterdam Consensus Workshop by expert obstetricians when two of the following criteria were recognized: oligomenorrhea and/or anovulation, clinical or biochemical signs of hyperandrogenism and ultrasound findings of polycystic ovary.9 Informed consent was obtained from all subjects before examination. The study was approved by the Institutional Review Board of Kırıkkale University and was conducted in accordance with the Declaration of Helsinki. Exclusion criteria of the study were systemic hypertension, coronary artery disease, diabetes mellitus, disorders of fat metabolism, any history of cerebrovascular or cardiovascular event, obesity (body mass index [BMI] > 30 kg/m2), history of smoking, use of systemic or local medications, high myopia, amblyopia, history of intraocular surgery, glaucoma, prior laser treatment, and retinal or optic nerve disorders. Each participant underwent a complete ophthalmological examination, including best-corrected visual acuity, intraocular pressure measurement, and slit-lamp examination including fundus examination. Doppler ultrasonography was performed in the morning between days 4 and 7 in oligomenorrhoeic and control women. One eye of each participant was randomly assigned to the study. A single radiologist experienced in Doppler ultrasonography performed all examinations. He was blinded to the presence of PCOS or any relevant clinical data about the patients and the controls. The patients were examined in a supine position with both eyes closed. The color Doppler imaging measurements were performed using an ultrasonographic device (LOGIQ 9) with a
12-(9–14)-MHz linear transducer. The transducer was applied to the closed eyelid using a coupling gel without applying any positive pressure on the globe. Real-time gray-scale and color-flow images were obtained. Angle correction was applied to the pulsed Doppler recordings to minimize errors in the measured velocities. The OA, the CRA, nasal posterior ciliary arteries (nPCA) and temporal posterior ciliary arteries (tPCA) were examined. The location of the optic nerve (ON) was identified initially, which is the most useful landmark for other retrobulbar vessels. The OA was identified approximately 15–20 mm posterior to the globe and the CRA was examined within the ON shadow. The nPCA were identified along the nasal side and tPCA along the temporal side of the ON behind the posterior sclera. Ocular blood flow indices of the peak systolic velocity (Vmax), diastolic velocity (Vd), end-diastolic velocity (Vmin), systolic/diastolic ratio (S/D), resistive index (RI), and pulsatility index (PI) were computed. Vascular resistance measurements expressed by the RI and PI were calculated automatically by the device. Blood pressure (BP) was measured in all subjects using an automatic device until systolic and diastolic blood pressures varied by less than 5 mmHg over three readings. Height and weight measurements were used to calculate the BMI. Peripheral blood samples were obtained from each participant and serum levels of luteinizing hormone (LH), folliclestimulating hormone (FSH), total testosterone, estradiol (E2), cholesterol, triglyceride (TRG), high-density lipoprotein (HDL), low-density lipoprotein (LDL), glucose and insulin were measured. All data were expressed as mean ± standard deviation (±SD). Statistical analyses were carried out using spss. The paired t-test was used to compare the variables between the PCOS group and controls and correlations were performed using Pearson’s correlation coefficient. A P-value < 0.05 was considered statistically significant.
Results The study included 41 eyes of 41 women with PCOS and 48 eyes of 48 healthy controls. Demographic characteristics, rate of amenorrhea and mean blood pressure measurements of the study groups are shown in Table 1. While the mean age was 21.49 ± 4.57 years (15–34 years) in the PCOS group, it was 21.10 ± 3.53 years
© 2015 The Authors Journal of Obstetrics and Gynaecology Research © 2015 Japan Society of Obstetrics and Gynecology
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Table 1 Clinical background of patients with PCOS and controls
Age (years) Height (cm) Weight (kg) Body mass index (kg/m2) Oligomenorrhea (%) Amenorrhea (%) Systolic blood pressure (mmHg) Diastolic blood pressure (mmHg)
PCOS group (n = 41)
Controls (n = 48)
P-value
21.49 ± 4.57 154.91 ± 5.34 66.40 ± 6.9 27.85 ± 5.37 29 (71) 12 (29) 121.90 ± 6.77 69.37 ± 2.92
21.10 ± 3.53 156.8 ± 5.41 62.81 ± 4.14 25.51 ± 2.78 0 0 110.27 ± 6.36 63.21 ± 2.92
0.656 0.496 0.351 0.224
