Pulsatile ocular blood flow during pregnancy

Estrogen dysregulation, intraocular pressure, and glaucoma risk

Characterized by optic nerve atrophy due to retinal ganglion cell (RGC) death, glaucoma is the leading cause of irreversible blindness worldwide. Of the major risk factors for glaucoma (age, ocular hypertension, and genetics), only elevated intraocular pressure (IOP) is modifiable, which is largely regulated by aqueous humor outflow through the trabecular meshwork. Glucocorticoids such as dexamethasone have long been known to elevate IOP and lead to glaucoma. However, several recent studies have reported that steroid hormone estrogen levels inversely correlate with glaucoma risk, and that variants in estrogen signaling genes have been associated with glaucoma. As a result, estrogen dysregulation may contribute to glaucoma pathogenesis, and estrogen signaling may protect against glaucoma. The mechanism for estrogen-related protection against glaucoma is not completely understood but likely involves both regulation of IOP homeostasis and neuroprotection of RGCs. Based upon its known activities, estrogen signaling may promote IOP homeostasis by affecting extracellular matrix turnover, focal adhesion assembly, actin stress fiber formation, mechanosensation, and nitric oxide production. In addition, estrogen receptors in the RGCs may mediate neuroprotective functions. As a result, the estrogen signaling pathway may offer a therapeutic target for both IOP control and neuroprotection. This review examines the evidence for a relationship between estrogen and IOP and explores the possible mechanisms by which estrogen maintains IOP homeostasis.

Evaluation of Choroidal Thickness during Pregnancy and Postpartum: A Longitudinal Study

Purpose

To assess the longitudinal changes of choroidal thickness using enhanced depth imaging optical coherence tomography (EDI-OCT) during pregnancy and postpartum.

Methods

The study included 23 eyes of 23 healthy pregnant women and 23 eyes of 23 healthy nonpregnant women. Choroidal thickness was measured manually with EDI-OCT at seven locations: The fovea, 500, 1000, and 1500 μm temporal (T) from the fovea and 500, 1000, and 1500 μm nasal (N) from the fovea. Measurements were obtained at each pregnancy trimester and 6 weeks postpartum and in the follicular phase of the menstrual cycle for the control group.

Results

The mean subfoveal choroidal thickness was 410.2 ± 82.4 μm, 434.8 ± 79.6 μm, 433.5 ± 80.3 μm, and 395.0 ± 71.1 μm in the first, second, and third trimesters and 6 weeks postpartum, respectively. In all seven measured locations, statistically significant changes were noted during pregnancy and postpartum in the choroidal thickness (P < 0.001). Choroidal thickness increased from the first trimester to the second and third trimester, after which it decreased at postpartum. Choroidal thickness was greater in the pregnant group during pregnancy and postpartum compared to the control group (P < 0.001).

Conclusions

This study indicated significant change in choroidal thickness at seven locations measured with EDI-OCT throughout pregnancy and 6 weeks after delivery. We showed that 6 weeks after delivery, choroidal thickness remains significantly higher than nonpregnant subjects.

The effect of postmenopausal hormonal drop on optic nerve head and peripapillary perfusion using optical coherence tomography angiography (OCTA)

We studied the effect of menopause with subsequent estrogen drop on optic nerve head structure and peripapillary vasculature. This cross-sectional analytic study was carried out on 100 eyes of 100 patients; patients were divided into a premenopausal group (50 eyes) and a postmenopausal group (50 eyes). Optical coherence tomography was done to evaluate retinal nerve fiber layer thickness (RNFLT) and optical coherence tomography angiography (OCTA) to assess the peripapillary capillary vessel density. RNFLT as well as the peripapillary vessel density (VD) were significantly lower in the postmenopausal group (P value < 0.001) with increasing age, hormonal drop, and higher intraocular pressure (IOP), specifically in the inferior quadrant. However, the negative correlation between IOP and VD (r = - 0.541) was stronger than its negative correlation with RNFLT (r = - 0.318). Postmenopausal hormonal changes lead to a significant rise in IOP-although still not glaucomatous- and a decrease in the RNFLT and perfusion of the optic nerve. This confirms the relation between hormonal drop and glaucoma in postmenopausal women. Changes in peripapillary vascular density were more evident than RNFL in correlation with IOP and age changes. So, OCTA can be used to detect early optic nerve affection.

Vascular Choroidal Alterations in Uncomplicated Third-Trimester Pregnancy

(1) Purpose: To evaluate the anatomy and perfusion of choroidal substructures in third-trimester pregnant women using optical coherence tomography (OCT) and OCT angiography (OCTA) imaging. (2) Methods: In this cross-sectional study, women in their third trimester of uncomplicated pregnancy and non-pregnant age-matched women were recruited. Participants underwent enhanced depth imaging (EDI) OCT and OCTA. Subfoveal choroidal thickness (SFCT), as well as choroidal sublayer perfusion, were compared between groups. (3) Results: In total, 26 eyes of 26 pregnant and 26 eyes of 26 non-pregnant women were included. The median age in both groups was 29 years. The median SFCT was 332 (211–469) µm in the pregnant group and 371.5 (224–466) µm in the non-pregnant cohort (p = 0.018). The median choriocapillaris perfusion (CCP) was significantly lower in the pregnant group (46% vs. 48%, p = 0.039). Moreover, Haller’s layer perfusion correlated significantly with mean arterial pressure in non-pregnant women (CC = 0.430, p = 0.028) but not in pregnant ones (CC = 0.054, p = 0.792). (4) Conclusions: SFCT was found to be thinner and CCP was lower in third-trimester pregnant women. Hormonal changes during pregnancy and consecutive impacts on autoregulation of small choroidal vessels might play an important role. Therefore, altered choroidal measurements during third-trimester pregnancy should be carefully evaluated as, to some extent, it could be a normal physiological change.

The thickness changes of retina in high myopia patients during the third trimester of pregnancy: a pilot study

Objectives

To observe and compare the difference in retinal thickness using optical coherence tomography (OCT) between patients with high myopia (HM) during the third trimester of pregnancy and age-matched HM non-pregnant women.

Methods

A case-control study. A total of 39 eyes from 39 HM women in the third trimester (study group) and 50 eyes of 50 age-matched non-pregnant women with HM (control group) were included. All subjects underwent SD-OCT examination. The built-in software was used to measure the retinal thickness in macular region. The data from two groups were compared using independent-samples t test.

Results

Among the 89 subjects in this study, the mean gestational age of the study group was 35.09 ± 2.44 weeks, and the average age was 32.24 ± 3.75 years. The average age of the control group was 34.04 ± 7.19 years old. Compared with the control group, the average thickness of parafoveal area, and the average thickness of parafoveal superior, inferior, temporal quadrants of the superficial retina and the average thickness of the foveal and parafoveal of the superficial retina were significantly decreased in the study group (P < 0.05). Compared with the control group, the average thickness of all quadrants of the retina in the parafoveal area except the nasal quadrant were significantly decreased in the study group (P < 0.05).

Conclusions

In this observational study, the retinal thickness of patients with high myopia during the third trimester of pregnancy was thinner than that of non-pregnant women with age-matched high myopia.

Identification of Estrogen Signaling in a Prioritization Study of Intraocular Pressure-Associated Genes

Elevated intraocular pressure (IOP) is the only modifiable risk factor for primary open-angle glaucoma (POAG). Herein we sought to prioritize a set of previously identified IOP-associated genes using novel and previously published datasets. We identified several genes for future study, including several involved in cytoskeletal/extracellular matrix reorganization, cell adhesion, angiogenesis, and TGF-β signaling. Our differential correlation analysis of IOP-associated genes identified 295 pairs of 201 genes with differential correlation. Pathway analysis identified β-estradiol as the top upstream regulator of these genes with ESR1 mediating 25 interactions. Several genes (i.e., EFEMP1, FOXC1, and SPTBN1) regulated by β-estradiol/ESR1 were highly expressed in non-glaucomatous human trabecular meshwork (TM) or Schlemm’s canal (SC) cells and specifically expressed in TM/SC cell clusters defined by single-cell RNA-sequencing. We confirmed ESR1 gene and protein expression in human TM cells and TM/SC tissue with quantitative real-time PCR and immunofluorescence, respectively. 17β-estradiol was identified in bovine, porcine, and human aqueous humor (AH) using ELISA. In conclusion, we have identified estrogen receptor signaling as a key modulator of several IOP-associated genes. The expression of ESR1 and these IOP-associated genes in TM/SC tissue and the presence of 17β-estradiol in AH supports a role for estrogen signaling in IOP regulation.

Case Report: Focal Choroidal Excavation: Conversion from Conforming to Nonconforming in a Pregnant Female

SIGNIFICANCE

Although rarely seen, clinicians should closely monitor patients, especially pregnant patients with focal choroidal excavation (FCE), as it can convert between subtypes and has been linked to pachychoroidal disease and potential for vision loss.

PURPOSE

This study aimed to report a case of the conversion of conforming FCE to nonconforming FCE with spontaneous resolution in a pregnant female.

CASE REPORT

A 35-year-old Indian woman presented with a slightly decreased vision in the right eye. The patient was 3 months pregnant at this visit. Her ocular history included stable conforming FCE in both eyes that was diagnosed 1 year earlier. Retinal pigmentary changes were noted in both eyes and consistent with previous examinations as being conforming FCEs in both eyes. Optical coherence tomography through the pigmented changes revealed FCE in the right eye with overlying serous fluid, with the left eye showing stable conforming FCE. She was diagnosed with a nonconforming FCE in the right eye secondary to her pregnancy. She was monitored with subsequent visits showing spontaneous resolution of the fluid and conversion back to a conforming FCE.

CONCLUSIONS

This case highlights the conversion of a conforming FCE to a nonconforming FCE with spontaneous resolution in a pregnant female. Similarities are seen in terms of pathophysiology with central serous chorioretinopathy, a fellow pachychoroidal disease, which also has pregnancy as a risk factor. Risk factors in pregnant patients such as increased cortisol and increased ocular blood flow may play an important part in the pathophysiology of the conditions, as they both result in choroidal hyperpermeability. Frequent monitoring and follow-up times are suggested for the patients. Lifelong monitoring is also indicated, as reoccurrences have been reported. Further research is needed at this time to elucidate the exact etiology of FCE and conversions between conforming and nonconforming FCE.

Investigation of Retinal Vascular Changes during Pregnancy Using Optical Coherence Tomography Angiography

Purpose: To investigate retinal vascular changes in pregnant women using optical coherence tomography angiography (OCTA).Materials and Methods: This prospective, cross-sectional study included 97 pregnant women and age-matched 34 healthy control subjects. The OCTA parameters of one eye (left) of pregnancy group and control group were compared. Besides, the OCTA parameters of three trimesters were compared between themselves and the control group. The foveal avascular zone (FAZ) area and the vessel density percentages of the superficial capillary plexus (SCP), deep capillary plexus (DCP), and radial peripapillary capillary (RPC) of all the groups were evaluated by OCTA.Results: In the pregnancy group, the vessel density of DCP was higher in all regions than the control group except the foveal region, but this difference could not reach statistical significance. On the other hand, the vessel density of SCP in the pregnancy group did not show a manifest change in all regions except the foveal region as in DCP. Although the FAZ area was wider in pregnancy group, this difference was not statistically significant (p:0.661). There was no statistically significant difference observed in vessel density of SCP, DCP, and RPC between the different trimesters and the control group, and none of these data correlated with the gestational week.Conclusion: This study showed retinal vascular changes secondary to pregnancy, especially in the vessel density of DCP. These results can provide information that should be taken into account in the evaluation and investigation of pregnancy-specific retinal vascular pathologies.

Comparison Between Central Choroidal Thickness in Pregnant Diabetic Females and Pregnant Non-Diabetic Females

Objective

To compare choroidal thickness in pregnant women with and without diabetes mellitus (DM).

Methods

Sixty pregnant females (60 eyes) were enrolled in this cross-sectional controlled study. They were divided into two groups: Group A (30 patients; 30 eyes) were pregestational diabetic pregnant females, while Group B (30 patients; 30 eyes) were non-diabetic pregnant females. Exclusion criteria were high-risk pregnancy, diabetic retinopathy in Group A subjects, systemic or ophthalmological pathology, drug intake other than vitamin supplements and diabetic medications, and large errors of refraction. All patients underwent full ophthalmological examination and enhanced depth imaging optical coherence tomography (EDI-OCT) to measure the choroidal thickness in the nine zones of the Early Treatment Diabetic Retinopathy Study (ETDRS) map.

Results

Our results show that Group A eyes (of pregnant diabetic females) had a highly significant greater choroidal thickness than Group B eyes (of pregnant non-diabetic females) in all nine zones of the ETDRS map (p-value <0.01). Moreover, we found a positive linear correlation between the duration of DM and the degree of choroidal thickening.

Conclusion

Pregnant diabetic females have a thicker choroid than that of pregnant non-diabetic females.

Evaluation of choroidal thickness and choroidal vascularity index during pregnancy

OBJECTIVE

To assess the choroidal structural characteristics in the first and third trimesters in pregnant women using enhanced depth imaging optical coherence tomography and binarization method.

DESIGN

Prospective study.

PARTICIPANTS

Twenty-five eyes of 25 pregnant women in the first trimester (group 1) and 25 eyes of 25 pregnant women in the third trimester (group 2) were examined. Healthy age-matched 25 participants were enrolled as a control group (group 3).

METHODS

The choroidal thickness (CT) was measured at 3 points; subfoveal, 1500 μm nasal to the fovea, and 1500 μm temporal to the fovea. Total choroidal area, luminal area, stromal area, stroma/lumen ratio, and choroidal vascularity index (CVI) were measured by Image-J software.

RESULTS

The mean subfoveal and nasal CT were statistically significantly increased in group 1 compared with controls (p = 0.005 and p = 0.004, respectively). The mean temporal CT was statistically significantly increased in group 1 compared with groups 2 and 3 (group 1 vs group 2, p = 0.043; group 1 vs group 3, p = 0.011). The mean total choroidal area, stromal area, and luminal area were significantly increased in groups 1 and 2 compared with control group (p < 0.001, p < 0.001, p < 0.001, and p < 0.001, p = 0.002, p = 0.002, respectively). There were no statistically significant differences among groups in terms of mean stroma/lumen ratio and CVI (p = 0.148 and p = 0.312, respectively).

CONCLUSIONS

There was a significant increase in subfoveal, temporal, and nasal CT in the first trimester. Total choroidal, stromal, and luminal areas were significantly increased in the first and third trimesters.

Ocular vascular changes during pregnancy: an optical coherence tomography angiography study

BACKGROUND

Pregnancy is a period presenting with many physiological adaptation mechanisms. One of the structures in which these mechanisms are observed is ocular tissues. The cornea, lacrimal and meibomian glands, and chorioretinal complex are all among the structures affected by changes during pregnancy. In this study we aimed to evaluate the macular and optic disc vessel density (VD) changes by Optical Coherence Tomography Angiography (OCTA) imaging in pregnancy.

METHODS

A total of 248 eyes from 124 pregnant women and 80 eyes from 40 healthy control women were involved. Vessel densities of macula were evaluated for superficial capillary plexus (SCP) and deep capillary plexus (DCP) in whole macula, foveal, parafoveal and perifoveal region. Peripapillary and whole optic disc VDs were also evaluated. Vessel densities of macula and optic disc were compared between control individuals and pregnant women. Vessel densities in different trimesters were also evaluated.

RESULTS

Modest but significant differences in VDs of whole macula of SCP and DCP were observed in pregnancy group. Additionally, perifoveal and parafoveal region of SCP, whole disc and radial peripapillary capillary VD were significantly higher in pregnancy group. There was no correlation between VD ratios of macula and optic disc and pregnancy weeks and trimesters.

CONCLUSIONS

This is the first study focusing on the OCTA parameters in pregnant individuals. These findings suggest that physiological changes during pregnancy are not limited to the cornea, eyelids and the choroid but also to the retinal and optic disc vasculature.

Macular choroidal thickness in highly myopic women during pregnancy and postpartum: a longitudinal study

Background

High myopia, a cause of serious visual impairment, is a significant global public health concern. We investigate longitudinal changes in macular choroidal thickness (CT) during pregnancy and 6-months postpartum in women with high myopia (HM).

Methods

A prospective longitudinal study was conducted in HM-pregnant women during the course of pregnancy (n = 42 eyes, 42 patients) and 6 months postpartum (n = 40 eyes, 40 patients, two cases lost).Macular CT was measured via enhanced-depth imaging (EDI)-optical coherence tomography (OCT) (EDI-OCT). Intraocular pressure (IOP), axial length (AL), refractive error, mean arterial pressure (MAP), mean ocular perfusion pressure (MOPP), and body mass index (BMI) were also measured.

Results

Macular CTs of HM pregnant women (214.3 ± 52.3 μm) had increased significantly during the third trimester of pregnancy compared with postpartum women (192.7 ± 51.9 μm, p = 0.014). No significant differences in AL, refractive error, or MAP were found between pregnant and postpartum groups (p > 0.05 for all parameters).During pregnancy, macular CT was negatively correlated with AL (first trimester: p = 0.010; second trimester: p = 0.013; and third trimester: p = 0.008) and positively correlated with refractive error (first trimester: p = 0.038; second trimester: p = 0.024; and third trimester: p = 0.010). No correlations between macular CT and age, IOP, MOPP, MAP, or BMI were found.

Conclusions

Our study revealed the presence of a significantly thicker choroid during the third trimester of pregnancy compared with 6-mo postpartum in HM women. Macular CT positively correlated with refractive error and negatively correlated with AL during pregnancy, but did not correlate with gestational age, MOPP, IOP, MAP, or BMI.

Comparison of Visual Function and Ocular Hemodynamics between Pre- and Post-Menopausal Women

Purpose

The incidence of eye disease increases with age and can often be linked to worsening cardiovascular function and increasing intraocular pressure. Estrogen is known to have vasodilatory effects in the systemic circulation. Decreased estrogen levels during menopause may therefore complicate or contribute to ocular pathologies as estrogen receptors are found in both retinal and choroidal tissue. The purpose of this investigation was to determine the effects of menopause on visual function and cardiovascular and ocular hemodynamics.

Methods

Twelve premenopausal and 24 postmenopausal women were evaluated at the Indiana University School of Medicine during a single study visit. Vision screening and ocular blood flow evaluations were performed, including blood pressure, heart rate, visual acuity, contrast sensitivity, intraocular pressure, and retinal capillary and retrobulbar blood flow imaging. Vision and ocular hemodynamics were compared using unpaired Student t-tests with pp<0.05 regarded as statistically significant.

Results

The premenopausal group had significantly lower heart rate (-16.1 b/m, p=0.0001) and systolic blood pressure (-17.7 mmHg, p=0.003) than postmenopausal subjects. Contrast sensitivity was significantly higher (measured in log units) in premenopausal women in both the right (0.25, p=0.039; 0.16, p=0.039) and left (0.45, p=0.001; 0.27, p=0.032) eyes at 9 and 18 cycles per degree, respectively. Premenopausal women also had significantly lower intraocular pressure in both the right (-2.19 mmHg, p=0.024) and left (-1.74 mmHg, p=0.035) eyes. Total ocular perfusion was not significantly different between groups.

Conclusions

This pilot work suggests that postmenopausal women have lower contrast sensitivity detection and elevated intraocular pressures compared to premenopausal women. Premenopausal women have lower cardiovascular risk factors, while total ocular circulation was similar to post-menopausal women.

Choroidal Thickness in Women with Uncomplicated Pregnancy: Literature Review

Pregnancy is a time when many changes occur in a woman's body. The goal of these changes is the provision of optimum conditions for the development of the foetus. Pregnancy also affects eye physiology. Well recognized physiological changes include a reduced corneal sensitivity, an increase in its central thickness and curvature, and a decrease in intraocular pressure. The association between choroidal thickness and pregnancy is not clear. Haemodynamic and hormonal changes taking place during pregnancy and the question of whether these changes are reflected by choroidal thickness are especially important. It is assumed that the choroid, which is one of the most highly vascularized tissues characterized by the highest blood flow to tissue volume ratio in the whole body, should respond by an increase in its thickness to an increase in blood flow and drop in the value of peripheral resistance. Measurement of choroidal thickness using enhanced depth imaging optical coherence tomography (EDI-OCT) in women with uncomplicated pregnancy provides important information concerning the effects of physiological changes in the eye.

Changes in intraocular pressure and central corneal thickness during pregnancy: a systematic review and Meta-analysis

AIM

To conduct a Meta-analysis for investigating the variations in intraocular pressure (IOP) and central corneal thickness (CCT) during normal pregnancy.

METHODS

We searched for clinical trials published up to November 2015 without language or region restrictions in PubMed, EMBASE, Web of Science, the Cochrane Central Register of Controlled Trials, Ovid, EBSCO, Elsevier, the Chinese Biomedicine Database, WanFang, CNKI, CQVIP and Google Scholar. Studies of the ocular changes observed in pregnant women were selected. The main outcomes were assessed by changes in IOP and CCT.

RESULTS

Fifteen studies were included. In subgroup analyses, IOP was significantly decreased during the second MD=-1.53, 95%CI (-2.19, -0.87); P<0.00001, and third MD=-2.91, 95%CI (-3.74, -2.08); P<0.00001 trimesters of pregnancy. CCT was increased during the second MD=10.12, 95%CI (2.01, 18.22); P=0.01, trimester of pregnancy; moreover, during the third trimester of pregnancy, the CCT displayed an increasing trend, but the difference was not significant MD=5.98, 95%CI (-1.11, 13.07); P=0.1.

CONCLUSION

A decrease in IOP is accompanied by an increase in CCT in the second and third trimesters of a normal pregnancy in women.

Changes in Subfoveal Choroidal Thickness During Pregnancy and After Delivery

BACKGROUND AND OBJECTIVE

This study was performed to investigate longitudinal changes in the subfoveal choroidal thickness (SFCT) during pregnancy and after delivery.

PATIENTS AND METHODS

The SFCT was measured in the first and third trimesters, shortly after delivery, and 1 month after delivery in 25 eyes of 25 women. Enhanced depth imaging optical coherence tomography was used for measurement.

RESULTS

The mean SFCT was 347 μm ± 86 μm, 329 μm ± 81 μm, 333 μm ± 81 μm, and 330 μm ± 87 μm in the first and third trimesters, shortly after delivery, and 1 month after delivery, respectively. The SFCT in the first trimester was significantly greater than that in the third trimester, shortly after delivery, and 1 month after delivery.

CONCLUSIONS

This study indicates that the SFCT is greater in the first trimester and decreases in the third trimester of pregnancy. The SFCT does not subsequently change until 1 month after delivery. [Ophthalmic Surg Lasers Imaging Retina. 2017;48:816-821.].

Transient Monocular Vision Loss on Awakening: A Benign Amaurotic Phenomenon

BACKGROUND

Transient monocular vision loss (TMVL) is an alarming symptom owing to potentially serious etiologies such as thromboembolism or giant cell arteritis. Our objective is to describe the phenomenon of TMVL present on awakening, which may represent a distinct and benign entity.

METHODS

We performed a retrospective observational case series of 29 patients who experienced TMVL on awakening. Patients who described monocular dimming or blackout of vision were included, and those with blurred vision, concurrent eye pain, and binocular vision loss were excluded. Descriptive statistics were used to summarize the study population.

RESULTS

Of the 29 patients we studied, 90% (n = 26) were female and 48% had crowded discs (cup-to-disc ratio ≤0.2). The mean age was 45.4 years, although women were significantly younger than men (mean ages 43.4 and 62.7 years, respectively, P = 0.017). Brain magnetic resonance imaging and vascular imaging (magnetic resonance angiography, computed tomographic angiography, or carotid Doppler) were performed in 69% and 55% of cases, respectively, and were uniformly negative. In 14 patients for whom clear follow-up data could be obtained, no medically or visually significant sequelae of this syndrome were found, and 50% experienced resolution of symptoms.

CONCLUSIONS

Evaluation was uniformly negative when patients described waking with isolated vision loss in 1 eye with subsequent resolution, usually in less than 15 minutes. The natural history seems benign with symptoms frequently remitting spontaneously. This visual phenomenon may represent an autoregulatory failure resulting in a supply/demand mismatch during low-light conditions.

Comparison of subfoveal choroidal thickness in healthy pregnancy and pre-eclampsia

PURPOSE

Pregnancy is a known predisposing factor for central serous chorioretinopathy (CSC). Choroidal thickness (CT) increases in patients with CSC. This study was designed to evaluate CT in pregnant women.Patients and methodsThis was a prospective study. Fourteen healthy pregnant women and seven patients with pre-eclampsia were included. Twenty-one normal subjects were also recruited. CT was measured using enhanced-depth imaging optical coherence tomography.

RESULTS

The mean CT of normal subjects, healthy pregnant women and patients with pre-eclampsia were 264.95±21.03, 274.23±29.30 and 389.79±25.13 μm, respectively (normal subjects vs healthy gravidas: P>0.05; normal subjects vs pre-eclampsia: P<0.001; healthy gravidas vs pre-eclampsia: P<0.001). CT decreased from 381.05±22.96 μm to 335.17±9.97 μm 1 week after delivery in patients with pre-eclampsia.

CONCLUSIONS

Pregnancy itself did not increase CT, whereas pre-eclampsia did appear to result in increased CT. This suggests that additional unknown factors induce hyperpermeability in pregnant women.

Measurement of choroidal thickness and macular thickness during and after pregnancy

AIM

To investigate the effect of pregnancy on subfoveal choroidal thickness (SFCT) and macular thickness in both pregnant and not pregnant healthy women.

METHODS

Twenty-nine healthy pregnant women in their third trimester and 36 age-matched healthy women were enrolled in a prospective, cross-sectional study. Foveal and parafoveal thickness in the four quadrants and SFCT were measured by optical coherence tomography (OCT) in the healthy pregnant women (i.e. study group) and healthy women (i.e. control group). OCT measurements were again measured 3mo after delivery in the study group.

RESULTS

Mean SFCT measurements in the control group, pregnant women of the study group, and after delivery of the study group were 320.86±59.18 µm, 387.97±59.91 µm, and 332.40±26.03 µm, respectively. There was a statistically significant difference in the mean SFCT values between pregnant women of the study group and the control group (P=0.000). Foveal and parafoveal thickness values were not statistically significant in either the study or control group.

CONCLUSION

SFCT increases during pregnancy and returns to normal range in the three months after delivery. Macular thickness does not show any change during pregnancy.

Choroidal thickness in pregnant women measured by enhanced depth imaging optical coherence tomography

PURPOSE

To measure choroidal thickness in healthy pregnant women using enhanced depth imaging optical coherence tomography (EDI-OCT) and compare the measurements with those of healthy non-pregnant women.

METHODS

Choroidal thickness was measured at the fovea and at 3 mm superior, inferior, temporal, and nasal to the fovea using EDI-OCT in both healthy pregnant and non-pregnant women.

RESULTS

The mean choroidal thickness in pregnant women was 275 ± 84 μm at the subfoveal and 307 ± 89, 277 ± 89, 274 ± 74, and 159 ± 60 μm at 3 mm superior, inferior, temporal, and nasal to the fovea, respectively. In comparison, the mean choroidal thickness in non-pregnant women was 273 ± 92 μm at the subfoveal and 301 ± 73, 290 ± 76, 293 ± 77, and 149 ± 55 μm at 3 mm superior, inferior, temporal, and nasal to the fovea, respectively. No significant statistical differences were found for choroidal thickness between the pregnant and non-pregnant women at any of the measurement points.

CONCLUSIONS

The results of this study demonstrate that the choroidal thickness was not significantly different between healthy pregnant and non-pregnant women.

Effect of aging on retinal circulation in normotensive healthy subjects

Although it is important to investigate the effects of normal aging on the ocular circulation, few studies have examined the effects of aging on the retinal microcirculation in healthy subjects. The purpose of this study was to evaluate the effects of aging on the retinal microcirculation in healthy men. Forty-five healthy men were divided into three groups based on age (young, middle-aged, elderly). We measured vessel diameter and blood velocity and calculated the retinal blood flow (RBF) and wall shear rate (WSR) in the retinal arteries. We performed pulse wave analysis obtained from the retinal blood velocity measurements. We also divided the subjects into two groups based on the presence or absence of prehypertension defined as 120-139/80-89 mmHg. No significant differences in vessel diameter, blood velocity, RBF, and WSR were seen among the groups. Pulse wave analysis showed significant increases in upstroke time (UT) in elderly men compared with young men (P < 0.05). Multiple regression analysis showed that the UT was correlated with age in all subjects. A significant difference was seen only in the UT between subjects with and without prehypertension. The UT calculated from the retinal blood velocity profile is associated significantly with aging, suggesting that measurement of the UT may detect the changes in the retinal and the systemic vessels with increasing age. The UT is the only parameter that increased significantly in subjects with prehypertension compared with those without prehypertension, suggesting that the UT may indicate the effects of prehypertension on the retinal arterioles.

Sex steroid and tropic hormone levels may be associated with postoperative prognosis of vitrectomy in Korean postmenopausal women: a pilot study

OBJECTIVE

The aim of this study was to evaluate the postoperative prognostic value of sex hormones and related biochemical markers for vitrectomy in postmenopausal Korean women.

METHODS

Twenty-three postmenopausal women undergoing vitrectomy who had not received hormone therapy were recruited. Before vitrectomy, hormonal profile such as follicle-stimulating hormone, estradiol, testosterone, tumor markers, and biochemical markers including homocysteine, glycosylated hemoglobin, protein, albumin, and lipid panel was measured. These parameters were correlated with ophthalmologic outcomes such as intraocular pressure, preoperative and postoperative visual acuity, and the visual improvement after surgery.

RESULTS

Follicle-stimulating hormone showed a positive correlation with the logarithm of the minimal angle of resolution value of postoperative visual acuity (Pearson's correlation, 0.583; P = 0.009). This significance was maintained after age or preoperative visual acuity was adjusted (P = 0.006 and P = 0.013, respectively). Testosterone also showed a positive correlation with intraocular pressure before and after adjustment for age (P = 0.027 and P = 0.033, respectively).

CONCLUSIONS

Sex steroid and tropic hormones may be associated with postoperative ophthalmologic outcomes in the postmenopausal women undergoing vitrectomy. Further larger scale studies will be necessary to confirm these preliminary results.

The effects of raloxifene hydrochloride on ocular hemodynamics and visual function

OBJECTIVE

To assess the comprehensive effects of raloxifene hydrochloride on retinal, choroidal and retrobulbar hemodynamics and on visual function in post-menopausal women.

DESIGN

Twenty-four post-menopausal women (age 55 +/- 3.8 years) were recruited for this cross-sectional study: 12 received placebo and 12 received raloxifene hydrochloride 60 mg once a day for 3 months. Baseline measurements of both groups included heart rate (HR), blood pressure (BP), visual acuity, contrast sensitivity and intraocular pressure (IOP) for both eyes. A comprehensive ocular blood flow (OBF) assessment was obtained for each patient in a randomly chosen study eye. Retinal blood flow data was obtained using confocal scanning laser Doppler flowmetry [Heidelberg Retinal Flowmeter (HRF)]. Color Doppler imaging (CDI) was used to assess retrobulbar hemodynamics in the ophthalmic, central retinal, short nasal and temporal posterior ciliary arteries. Baseline vision and hemodynamics in post-menopausal subjects were compared using paired Student's t tests, and the percentage change in baseline versus 3-month parameters was analyzed.

RESULTS

There were no statistically significant differences between 3 months of raloxifene therapy and placebo in terms of age, HR, arterial or mean BP, visual acuity, contrast sensitivity, IOP or retinal or retrobulbar blood flow.

CONCLUSION

Raloxifene therapy at 60 mg/day had no clinically significant impact on BP, IOP or OBF in post-menopausal women.

Does Postmenopausal Hormone Replacement Therapy Affect Intraocular Pressure?

PURPOSE

To assess the effects of postmenopausal hormone replacement therapy (HRT) on intraocular pressure (IOP).

PATIENTS AND METHODS

This was a cross-sectional controlled study, including 107 women aged 60 to 80 years receiving HRT and 107 controls who have never received HRT. All subjects underwent IOP assessment and funduscopic photography for cup-to-disc (C/D) ratios, and completed questionnaires regarding personal and family history of glaucoma, hormone replacement therapy, lifetime estrogen and progesterone exposure, and cardiovascular risk factors. Main Outcome Measures included IOP, prevalence of increased IOP, and C/D ratios.

RESULTS

The groups did not differ in mean IOP (15.3 versus 15.3 mm Hg), mean vertical (0.18 versus 0.21) and horizontal (0.17 versus 0.14) C/D ratios, and in prevalence of increased IOP (15% versus 14%), C/D ratio (7% versus 7%), or glaucoma (9% versus 11%). A personal history of ischemic heart disease was the only risk factor associated with increased IOP (O.R. = 4.63, P = 0.003). Lifetime estrogen and progesterone exposure, including pregnancies, deliveries, menstruation years, and the use of oral contraceptives did not significantly affect the risk for increased IOP.

CONCLUSION

Hormone replacement therapy and lifetime estrogen and progesterone exposure do not seem to affect IOP or the risk for increased IOP. A personal history of ischemic heart disease may be associated with a higher risk for this disorder.

Effect of the menstrual cycle on the optic nerve head in diabetes: analysis by confocal scanning laser ophthalmoscopy

BACKGROUND

The purpose of this study was to examine and compare menstrual-cycle-dependent topographic changes in the optic nerve head of normally menstruating women with different grades of type 2 diabetes mellitus.

METHODS

We studied the right eyes of 123 normally menstruating women (36 with severe nonproliferative diabetic retinopathy [NPDR], 42 with mild NPDR and 45 healthy subjects). All subjects underwent a complete ocular examination at baseline. At 4 hormonally distinct phases of the menstrual cycle (early follicular, late follicular, mid-luteal and late luteal), we analysed the topography of the optic nerve head, using a confocal scanning laser ophthalmoscope, and measured the serum levels of estradiol, progesterone and luteinizing hormone.

RESULTS

We excluded from analysis the data for 8 patients with severe NPDR, 10 patients with mild NPDR and 15 control subjects who were lost to follow-up examinations during the menstrual cycle. The mean age and optic disc area did not differ significantly among the 3 groups. The duration of diabetes was significantly longer in the patients with severe NPDR than in those with mild NPDR (p < 0.05). The women with severe NPDR had a significantly increased neuroretinal rim area and a significantly decreased cup-shape measure, linear cup/disc ratio, cup/disc area ratio and cup area in the late luteal phase compared with the other phases of the menstrual cycle (p < 0.05). Those with mild NPDR or a normal retina had no significant topographic changes in the optic nerve head during the menstrual cycle.

INTERPRETATION

Severe NPDR is associated with significant topographic changes in the rim and cup of the optic nerve head during the menstrual cycle. This must be considered in the evaluation of women with both diabetes and glaucoma. The normal fluctuations in serum sex hormone levels during the menstrual cycle of diabetic women seem to affect the optic nerve head more when the disease is advanced.

Branch retinal arterial occlusion associated with toxoplasmic chorioretinitis

BACKGROUND

Ocular toxoplasmosis can cause a variety of retinal vascular changes including branch retinal arterial occlusion, which is a rare complication of the disease.

PATIENT AND METHODS

We report a case of toxoplasmic chorioretinitis in a pregnant woman, who developed branch retinal arterial obstruction adjacent to the active chorioretinitis lesion.

RESULTS

The patient received an appropriate steroid and antibiotic treatment and the retinitis lesion resolved over a six-week period. At two months after diagnosis, visual acuity in her right eye was 20/30 and there was a hyperpigmented scar at the site where active retinitis had been observed.

CONCLUSION

Especially in young patients with branch retinal vascular occlusion associated with posterior uveitis, the diagnosis of ocular toxoplasmosis should be kept in mind and serologic test results should be obtained.

The influence of sex hormones on ocular blood flow in women

PURPOSE

To investigate the influence of sex hormones on ocular haemodynamics, blood flow velocities in the ophthalmic and central retinal arteries and serum levels of sex hormones were measured in pre- and postmenopausal women.

METHODS

Colour Doppler imaging (CDI) was used to determine the flow velocities (peak systolic velocity [PSV] and end-diastolic velocity [EDV]) and the resistive index (RI) in the ophthalmic and central retinal arteries in 22 premenopausal and 32 postmenopausal women, who had never received hormone replacement therapy. Serum levels were measured for oestradiol, free testosterone and follicle-stimulating hormone. The CDI parameters were compared between the two groups and the influence of serum levels of oestradiol and testosterone on blood flow velocities and the resistive indices were analysed.

RESULTS

After correcting for age and mean arterial blood pressure, an analysis of covariance disclosed a significantly lower EDV (p=0.02) and a significantly higher RI (p=0.01) in the central retinal artery of postmenopausal women compared with premenopausal women. Partial correlation analysis, controlling for age, revealed significant correlations between the CDI parameters and serum levels of oestradiol and testosterone. For premenopausal women, PSV (r=0.58, p=0.04) and EDV (r=0.73, p=0.006) in the ophthalmic artery correlated positively with serum oestradiol levels. The RI in the central retinal artery decreased with increasing oestradiol levels in both groups (premenopausal r= -0.40, p=0.04; postmenopausal r= -0.32, p=0.05). Peak systolic velocity in the central retinal artery correlated negatively (r= -0.49, p=0.04), whereas the RI correlated positively (r=0.53, p=0.02) with testosterone levels in the premenopausal group. Postmenopausal women with higher testosterone levels had lower EDV (r= -0.53, p=0.007) in the central retinal artery and higher RI in both vessels (ophthalmic artery r=0.48, p=0.01; central retinal artery r=0.61, p=0.002).

CONCLUSION

Our data provide evidence of a relationship between serum sex hormone levels and blood flow velocities and resistive indices in retrobulbar arteries. Oestradiol appears to have beneficial effects on ocular haemodynamics, whereas testosterone may act as an antagonistic to the effects of oestrogen.

Evaluating pulsatile ocular blood flow analysis in normal and treated glaucomatous eyes

PURPOSE

To evaluate pulsatile ocular blood flow (POBF) analysis in normal subjects and glaucoma patients by comparison of POBF measurements with functional (as determined by visual field [VF]) and structural (as determined by optical coherence tomography [OCT]) measures.

DESIGN

Prospective, cross-sectional study.

METHODS

Forty-one eyes of 24 consecutive glaucoma patients and 20 eyes of 10 healthy subjects were studied; POBF analysis was performed on all subjects at the same visit as VF testing and OCT retinal nerve fiber layer (NFL) thickness measurement. The mean results of normal and glaucomatous eyes were compared for each method. Correlation between measurements obtained with each modality and the discriminating power using receiver operator characteristic curves was tested.

RESULTS

The mean POBF (standard deviation [SD]) in the normal group was 1,010.4 (292.8) microl/min and 989.3 (305.5) microl/min in the glaucoma group (P =.90). Significant differences between groups were found for VF mean deviation and pattern standard deviation (P =.02, P =.004, respectively) and OCT mean NFL thickness (P <.0001). No correlation was found between POBF parameters and intraocular pressure, VF, or OCT variables except for intraocular pressure in glaucoma group (r = -.43, P =.003). The area under the receiver operator characteristic curves was higher for VF indexes and OCT mean NFL thickness than POBF parameters for distinguishing between normal and glaucomatous eyes.

CONCLUSIONS

The wide range of normal values and the low discriminating power of POBF between normal and glaucomatous eyes limits the clinical use of the device for glaucoma patients.

Ocular changes in pregnancy

Visual changes in pregnancy are common, and many are specifically associated with the pregnancy itself. Serous retinal detachments and blindness occur more frequently during preeclampsia and often subside postpartum. Pregnant women are at increased risk for the progression of preexisting proliferative diabetic retinopathy, and diabetic women should see an ophthalmologist before pregnancy or early in the first trimester. The results of refractive eye surgery before, during, or immediately after pregnancy are unpredictable, and refractive surgery should be postponed until there is a stable postpartum refraction. A decreased tolerance to contact lenses also is common during pregnancy; therefore, it is advisable to fit contact lenses postpartum. Furthermore, pregnancy is associated with a decreased intraocular pressure in healthy eyes, and the effects of glaucoma medications on the fetus and breast-fed infant are largely unknown.

TARGET AUDIENCE

Obstetricians & Gynecologists, Family Physicians.

LEARNING OBJECTIVES

After completion of this article, the reader will be able to list the various ocular changes that occur during pregnancy, summarize the ocular disturbances that occur with preeclampsia and diabetes, and describe the management of some ocular problems during pregnancy.