Superficial Vascular Plexus Research Articles

RAPID MACULAR CAPILLARY LOSS IN PATIENTS WITH UNCONTROLLED TYPE 1 DIABETES.

To analyze the evolution of macular vessel density (VD) over 1 year, during early worsening of diabetic retinopathy, in patients with uncontrolled Type 1 diabetes (T1D). Retrospective study of 12 eyes of 9 patients with T1D with early worsening of diabetic retinopathy imaged with optical coherence tomography angiography. The following data were collected at the time of pan retinal photocoagulation initiation and after 6 and 12 months: vessel density within three retinal plexuses-superficial vascular plexus, intermediate capillary plexus, and deep capillary plexus; foveal avascular zone area, acircularity index, and flow density (FD)-300; central macular thickness; and HbA1c levels. A history of rapid reduction in blood glucose was found in seven of nine cases. Vessel density was significantly decreased at 12 months in all plexuses: from 44.68 ± 4.75 to 40.23 ± 7.13 in the superficial vascular plexus (P = 0.008), from 42.72 ± 4.86 to 37.12 ± 8.64 in the intermediate capillary plexus (P = 0.03), and from 22.68 ± 3.93 to 19.66 ± 4.92 in the deep capillary plexus (P = 0.004). Intermediate capillary plexus and deep capillary plexus changes were strongly correlated (r = 0.86, P < 0.001) and were significant as early as 6 months. The mean foveal avascular zone area increased (P = 0.05) and the FD-300 decreased (P = 0.03). No significant change in acircularity index, central macular thickness, and visual acuity were observed over time. Early worsening of diabetic retinopathy induces a rapid macular capillary dropout mainly affecting the intermediate capillary plexus and deep capillary plexus.

Thresholding strategies to measure vessel density by optical coherence tomography angiography

ObjectiveA variety of binarization strategies have been used to measure vessel density by optical coherence tomography angiography (OCT-A), but it is uncertain if they produce similar results. The purpose of the study was to evaluate the impact of different thresholding methods and contrast and brightness adjustment on OCT-A vessel density metrics. DesignObservational, cross-sectional case series. ParticipantsConsecutive healthy volunteers. MethodsHealthy volunteers underwent fovea-centred 3 mm × 3 mm OCT-A scans using PlexElite 9000. Images of the superficial vascular plexus were generated using the instrument’s automated segmentation. Images were thresholded with 5 different threshold tools in ImageJ (Default, Huang, IsoDat, Mean, and Otsu), and the threshold grey level value defined by each method was recorded. Brightness and contrast were also increased or decreased by 50% compared with the default. Binarization was performed using the threshold values from each method, and vessel densities were computed and compared. Main outcome measuresSuperficial plexus vessel density was measured and compared using different adjust threshold tools and changing brightness and contrast. ResultsTwenty eyes of 20 healthy participants were included. Different threshold strategies produced measurements with different mean values (p < 0.0001). Pairwise comparisons revealed differences between all groups (p < 0.0001) except between the IsoData and Otsu thresholding approaches (p > 0.270). Increasing or decreasing the brightness or to 50% of the mean value also yielded statistically significant differences (p < 0.0001). ConclusionsThe method of thresholding and adjustments in contrast and brightness can significantly impact retinal vessel density measurements. These findings highlight the importance of using consistent thresholding strategies for clinical studies.

Optical coherence tomography angiography reveals vascular alterations in pediatric commotio retinae.

Aim of this study is to present the acute and long-term swept-source optical coherence tomography angiography findings in pediatric commotio retinae. Two children presented with reduced visual acuity and Berlin edema after blunt trauma. Swept-source optical coherence tomography revealed hyperreflectivity of the retinal nerve fiber layer and disruption of the ellipsoid zone and the retinal pigment epithelium. Swept-source optical coherence tomography angiography showed enlarged superficial foveal avascular zone in both cases. In the more severe case, there was enlargement of both superficial and deep foveal avascular zone, and reduction of the superficial vascular plexus density. The present findings suggest that pediatric commotio retinae may be associated with retinal vascular changes, that is, foveal avascular zone enlargement and decreased vessel density. The extent of the microvascular alterations is possibly related to trauma severity.

Targeting connexin37 alters angiogenesis and arteriovenous differentiation in the developing mouse retina.

Connexin37 (Cx37) forms intercellular channels between endothelial cells (EC), and contributes to coordinate the motor tone of vessels. We investigated the contribution of this protein during physiological angiogenesis. We show that, compared to WT littermates, mice lacking Cx37 (Cx37-/- ) featured (i) a decreased extension of the superficial vascular plexus during the first 4days after birth; (ii) an increased vascular density at the angiogenic front at P6, due to an increase in the proliferative rate of EC and in the sprouting of the venous compartment, as well as to a somewhat displaced position of tip cells; (iii) a decreased coverage of newly formed arteries and veins by mural cells; (iv) altered ERK-dependent endothelial cells proliferation through the EphB4 signaling pathway, which is involved in the specification of veins and arteries. In vitro studies documented that, in the absence of Cx37, human venous EC (HUVEC) released less platelet-derived growth factor (PDGF) and more Angiopoietin-2, two molecules involved in the recruitment of mural cells. Treatment of mice with DAPT, an inhibitor of the Notch pathway, decreased the expression of Cx37, and partially mimicked in WT retinas, the alterations observed in Cx37-/- mice. Thus, Cx37 contributes to (i) the early angiogenesis of retina, by interacting with the Notch pathway; (ii) the growth and maturation of neo-vessels, by modulating tip, stalk, and mural cells; (iii) the regulation of arteriovenous specification, thus, representing a novel target for treatments of retina diseases.

Deep iterative vessel segmentation in OCT angiography.

This paper addresses retinal vessel segmentation on optical coherence tomography angiography (OCT-A) images of the human retina. Our approach is motivated by the need for high precision image-guided delivery of regenerative therapies in vitreo-retinal surgery. OCT-A visualizes macular vasculature, the main landmark of the surgically targeted area, at a level of detail and spatial extent unattainable by other imaging modalities. Thus, automatic extraction of detailed vessel maps can ultimately inform surgical planning. We address the task of delineation of the Superficial Vascular Plexus in 2D Maximum Intensity Projections (MIP) of OCT-A using convolutional neural networks that iteratively refine the quality of the produced vessel segmentations. We demonstrate that the proposed approach compares favourably to alternative network baselines and graph-based methodologies through extensive experimental analysis, using data collected from 50 subjects, including both individuals that underwent surgery for structural macular abnormalities and healthy subjects. Additionally, we demonstrate generalization to 3D segmentation and narrower field-of-view OCT-A. In the future, the extracted vessel maps will be leveraged for surgical planning and semi-automated intraoperative navigation in vitreo-retinal surgery.

Does the Foveal Avascular Zone Change in Glaucoma?

The foveal avascular zone (FAZ) - with perimeter and acircularity index (AI) and surrounding vessel density - are measured in glaucomatous eyes in comparison to healthy eyes - with additional subdivision into visual field defects in different locations (central vs. peripheral). The data from 128 eyes were evaluated. Firstly, glaucomatous eyes (n = 74) were compared with healthy eyes (n = 54). In addition, glaucomatous eyes with a central visual field defect (ZGD, n = 19) and eyes with peripheral visual field defect (PGD, n = 34) were differentiated. The FAZ area, its perimeter and roundness, as well as the parafoveal vessel density (VD), were calculated by means of optical coherence tomography angiography in the superficial and deep vascular plexus. Glaucomatous eyes have no significant change in FAZ, its perimeter or the AI compared to healthy eyes. However, dividing the glaucomatous eye by visual field defect reveals that the eyes with a central defect have a significantly larger FAZ than those with a peripheral defect and the perimeter is also significantly larger. The AI shows no significant difference depending on the localisation of visual field defects. The macular/foveal VD is significantly lower in the ZDG group. In glaucoma, the FAZ enlarges when the visual field defect is centralised and VD decreases significantly in the area of fovea.

Factors Affecting Repeatability of Foveal Avascular Zone Measurement Using Optical Coherence Tomography Angiography in Pathologic Eyes.

PurposeTo determine factors that may affect the repeatability of the foveal avascular zone (FAZ) measurement obtained using optical coherence tomography angiography (OCTA) including instrument type, image segmentation, image quality, and fundus pathology.Patients and MethodsThis prospective single-center study enrolled 43 subjects (85 eyes) with retinal vasculopathy, macular edema, optic pathology or normal contralateral eye. The macula was imaged twice using Optovue Angiovue and once using Cirrus Angioplex to obtain 3x3mm OCTA images centered on the fovea. Images were generated by the same operator within 30 mins. The FAZ size for the entire retinal thickness (“overall FAZ”) was measured automatically using the OCTA software. The FAZ size of the superficial and deep retinal vascular plexus layers was measured manually using the enface OCTA images of the segmented layers and Image J analysis. Intraclass correlations coefficient (ICC) was calculated to determine repeatability.ResultsFor the overall FAZ measurement, repeatability was excellent (ICC 0.953 right eye, 0.938, left eye) using the same machine (intra-instrument) and somewhat lower but still good to excellent (ICC 0.803 right eye, 0.917 left eye) using machines made by different vendors (inter-instrument). For the segmented layers, intra-instrument repeatability of FAZ measurement was excellent (ICC > 0.95) for both plexus layers. Inter-instrument repeatability was good for the superficial plexus layer (ICC 0.86 right eye, 0.88 left eye) but reduced for the deep plexus layer (ICC 0.63 right eye, 0.57 left eye). Suboptimal image quality and presence of retinal vasculopathy and macular edema tended to reduce FAZ repeatability but to a lesser degree.ConclusionInter- and intra-instrument repeatability of the overall FAZ measurement was high using commercial OCTA instruments and only mildly reduced by suboptimal image quality and fundus pathology. For segmented layers, intra-instrument repeatability remained high but inter-instrument repeatability was reduced for the deep plexus layer.

Retinal neurovascular changes in chronic kidney disease

To examine retinal neurovascular changes in patients with chronic kidney disease (CKD). Case-control study. A total of 171 CKD cases and 40 controls were recruited (mean age 62.9±10.3 versus 60.8±9.2, p=0.257). Retinal neural parameters, including parafoveal retinal thickness (PfRT), macular ganglion cell complex thickness (GCCt), global loss volume (GLV), focal loss volume (FLV) and peripapillary retinal nerve fibre layer thickness (RNFLt), were measured using optical coherence tomography (OCT). Microvascular parameters, including foveal avascular zone size, vessel density over the parafoveal superficial vascular plexus (SVP-VD), parafoveal deep vascular plexus (DVP-VD) and radial peripapillary capillary (RPC-VD), were measured using OCT angiography. Chronic kidney disease (CKD) patients showed reduced PfRT, GCCt and RNFLt and increased GLV and FLV compared with the controls (all p<0.005). Among patients with CKD, estimated glomerular filtration rate was an independent factor associated with PfRT (coefficient 0.19, p=0.015), GCCt (coefficient 0.10, p=0.006), GLV (coefficient-0.08, p=0.001), FLV (coefficient-0.02, p=0.006) and RNFLt (coefficient 0.15, p=0.002). Parafoveal retinal thickness (PfRT), GCCt, GLV, FLV and RNFLt were correlated with SVP-VD (all p<0.001) but not with DVP-VD (all p>0.1). Chronic kidney disease (CKD) patients demonstrated a significant reduction in macular thickness and changes in retinal neural parameters. These changes were associated with the severity of CKD and correlated with the microvascular rarefaction in the parafoveal SVP.

Association Between Clinical Biomarkers and Optical Coherence Tomography Angiography Parameters in Type 2 Diabetes Mellitus.

PurposeTo investigate the clinical significance of the changes in the macular microvasculature in patients with diabetes mellitus type 2 without diabetic retinopathy.MethodsFifty-five patients with diabetes mellitus type 2 without diabetic retinopathy and 48 healthy individuals were enrolled in a prospective cross-sectional study. We identified the changes of optical coherence tomography angiography parameters (foveal avascular zone [FAZ] area and circularity, vessel density, and perfusion index) of the 6 × 6-mm macular scan. Correlation and multiple regression analyses were performed between optical coherence tomography angiography parameters and previously known diabetes mellitus type 2-related demographic and systemic characteristics, and serum biochemical markers.ResultsFAZ parameters and perfusion index of the superficial and deep vascular plexus showed significant correlation with serum insulin level, and homeostasis model assessment indices. In multiple linear regression analysis, low insulin levels predicted increased FAZ areas in both the superficial (β = –0.007; P = 0.030) and deep layers (β = –0.010; P = 0.018) and a decreased perfusion index in the deep layer (β = 0.003; P = 0.001).ConclusionsThe expansion and loss of circularity of the FAZ and the decrease in the perfusion index may be affected by insulin resistance and secretory capacity in patients with diabetes mellitus type 2 with no diabetic retinopathy.

Asymmetry analysis of macular optical coherence tomography angiography in patients with glaucoma and healthy subjects

Background/aimsQuantitative analysis of optical coherence tomography angiography (OCT-A) images requires a reproducible approach that accounts for sectoral loss. The objective of this study was to determine whether an index that...

Response of the Trilaminar Retinal Vessel Network to Intraocular Pressure Elevation in Rat Eyes.

PurposeThe purpose of this study was to test the hypothesis that the superficial, intermediate, and deep retinal vascular plexus show different responses to intraocular pressure (IOP) elevation.MethodsAnesthetized adult Long Evans rats (n = 14) were imaged using optical coherence tomography angiography (OCTA; Spectralis) at baseline (IOP 10 mm Hg) and in follow-up mode to examine the vasculature during IOP elevation (10 to 110 mm Hg, 10 mm Hg steps, each step 3 minutes). A 20° × 10° field was imaged. Vessel density within a 2D projection image was determined (%) for the superficial vascular complex (SVC), intermediate capillary plexus (ICP), and deep capillary plexus (DCP). Comparisons were made between layers using 2-way repeated measures ANOVA (layer versus IOP) following normalization to baseline (% relative to 10 mm Hg).ResultsThe three vascular layers responded differently to IOP elevation. For IOPs between 40 and 60 mm Hg, DCP and ICP capillaries were significantly more resistant to IOP elevation than those in the SVC. When IOP was elevated above 70 mm Hg, all layers showed reduced vessel density. IOP induced change in SVC vessel density closely followed reductions in thickness of the inner retinal layers (nerve fiber, ganglion cell, and inner plexiform layer). This close relationship between reductions in tissue thickness and vessel density was less apparent for the ICP and DCP.ConclusionsThese data show that the intermediate and deep vascular plexus in the rat retina have a greater capacity for autoregulation against mild IOP elevation but are more affected at high IOP.

Transient effect of suction on the retinal neurovasculature in myopic patients after small-incision lenticule extraction.

To characterize retinal neurovasculature changes after small-incision lenticule extraction (SMILE) in myopic patients. Ophthalmic Center, the Second Affiliated Hospital of Guangzhou Medical University, China. Prospective interventional study. The corrected distance visual acuity/uncorrected distance visual acuity, corrected intraocular pressure (CIOP), and corneal tomography were evaluated at baseline (PRE), postoperative day (POD) 1, and POD 7. Ganglion cell-inner plexiform layer (GCIPL) and peripapillary retinal nerve fiber layer (pRNFL) thicknesses were measured. The vessel area densities (VADs, %), vessel skeleton densities (VSDs, %), vessel diameter index (VDI), and fractal dimensions (Dbox) of the superficial vascular plexus (SVP) and deep vascular plexus (DVP) were measured in a circular area (ϕ 2.5 mm) centered on the fovea. A total of 38 myopic patients were recruited. The GCIPL thickness was increased after SMILE at POD 1 and POD 7 (P < .01) but no significant changes in the pRNFL thickness. The VAD, VSD, and Dbox of the SVP were decreased at POD 1 (P < .01), but not at POD 7. The VDI in small vessels of the SVP and DVP was decreased at POD 1 (P < .05) and increased at POD 7 (P < .05). Changes in CIOP were positively correlated with changes in the GCIPL thickness. Changes in CIOP were negatively correlated with changes in the VAD of small vessels and the Dbox of total vessels in the DVP. Changes in CIOP were negatively correlated with the VSD and VDI of small vessels in the DVP and changes in the VDI of big vessels in the SVP. The transient fluctuations in the retinal neurovasculature after SMILE may represent a characteristic homeostasis pattern in patients after refractive surgery.

Retinal Capillary Plexus Pattern and Density from Fovea to Periphery Measured in Healthy Eyes with Swept-Source Optical Coherence Tomography Angiography

Optical coherence tomography angiography is evolving towards wider fields of view. As single widefield acquisitions have a lower resolution, preventing an accurate segmentation of vascular plexuses in the periphery, we examined the retinal vascularisation from the macula to the periphery in all retinal quadrants, using 3 × 3-mm volume scans, to obtain montages with sufficient image resolution up to 11 mm from the foveal centre. Images were qualitatively and quantitatively analysed, using C- and B-scan approaches to calculate the capillary density (CD) and the interplexus distance (IPD). Three vascular plexuses (i.e., superficial vascular plexus: SVP, intermediate capillary plexus: ICP, and deep capillary plexus: DCP) were observed up to the mid-periphery in all sectors. The CD of the SVP decreased from about 5 mm of eccentricity, along with ganglion cell density decrease. The CD of the ICP progressively decreased from the fovea towards the periphery, along with the retinal thinning and then vanished from 8 to 9 mm of eccentricity, becoming undetectable beyond. This ICP disappearance resulted in an increased IPD between the SVP and the DCP in an area known to be frequently affected by capillary drop-out in diabetic retinopathy. The DCP only showed a slightly decreased CD towards the retinal periphery.

Transient Effect of Suction on Retinal Neuro-vasculature in Myopic Patients after Small Incision Lenticule Extraction

In Brief Purpose: To characterize retinal neurovasculature changes after small-incision lenticule extraction (SMILE) in myopic patients. Setting: Ophthalmic Center, the Second Affiliated Hospital of Guangzhou Medical University, China. Design: Prospective interventional study. Methods: The corrected distance visual acuity/uncorrected distance visual acuity, corrected intraocular pressure (CIOP), and corneal tomography were evaluated at baseline (PRE), postoperative day (POD) 1, and POD 7. Ganglion cell-inner plexiform layer (GCIPL) and peripapillary retinal nerve fiber layer (pRNFL) thicknesses were measured. The vessel area densities (VADs, %), vessel skeleton densities (VSDs, %), vessel diameter index (VDI), and fractal dimensions (Dbox) of the superficial vascular plexus (SVP) and deep vascular plexus (DVP) were measured in a circular area (ϕ 2.5 mm) centered on the fovea. Results: A total of 38 myopic patients were recruited. The GCIPL thickness was increased after SMILE at POD 1 and POD 7 (P < .01) but no significant changes in the pRNFL thickness. The VAD, VSD, and Dbox of the SVP were decreased at POD 1 (P < .01), but not at POD 7. The VDI in small vessels of the SVP and DVP was decreased at POD 1 (P < .05) and increased at POD 7 (P < .05). Changes in CIOP were positively correlated with changes in the GCIPL thickness. Changes in CIOP were negatively correlated with changes in the VAD of small vessels and the Dbox of total vessels in the DVP. Changes in CIOP were negatively correlated with the VSD and VDI of small vessels in the DVP and changes in the VDI of big vessels in the SVP. Conclusions: The transient fluctuations in the retinal neurovasculature after SMILE may represent a characteristic homeostasis pattern in patients after refractive surgery. There are transient retinal neurovasculature fluctuations after SMILE. Changes in the GCIPL thickness were positively correlated with changes in CIOP. Changes in the vasculature of the SVP and DVP were negatively correlated with changes in CIOP.

联合或者单独使用利伐沙班治疗青斑样血管病三例

Livedoid vasculopathy is a rare chronic ischemic necrotic skin disease caused by microvascular thrombosis in superficial vascular plexuses. Effective treatments are lacking. Efficacy of anticoagulants has been clinically proven in the treatment of this disease, but the administration route and adverse reactions limit their extensive application. The new oral factor Xa inhibitor rivaroxaban, which has many advantages, such as no need for coagulation monitoring, few adverse reactions and convenient oral administration, can be used in the prevention and treatment of thrombosis and post-thrombotic ulcers. In this article, 3 patients with livedoid vasculopathy were treated with rivaroxaban alone or in combination, and satisfactory efficacy was obtained. Key words: Skin diseases, vascular; Anticoagulants; Treatment outcome; Livedoid vasculopathy; Rivaroxaban

Visual Function and Disability Are Associated with Increased Retinal Volumetric Vessel Density in Patients with Multiple Sclerosis

The goal of this study was to determine the volumetric vessel density (VVD) in the intraretinal layers and its relationship with visual function and disability in patients with multiple sclerosis (MS). Cross-sectional study. A total of 80 patients with relapsing-remitting MS and 99 age- and sex-matched healthy controls (HC) were recruited. The retinal microvascular network in the macular area was imaged using optical coherence tomography angiography in 123 eyes without a history of optic neuritis (ON) (MSNON) and 36 eyes with a history of ON (MSON). The VVD was calculated as the vessel densities in the retinal vascular network (RVN), superficial vascular plexus (SVP), or deep vascular plexus (DVP) of an annulus (0.6-2.5mm in diameter), divided by the corresponding tissue volume of the intraretinal layers respectively. The VVD of RVN and DVP in MSNON were significantly higher than in HC (P < .05). The VVD of RVN, SVP, and DVP in MSON were significantly higher than in MSNON and HC (P < .05). The VVD in both RVN and SVP were positively related to EDSS and disease duration, but negatively related to low-contrast letter acuity (P < .05). The VVD measurements were also negatively and strongly related to the corresponding tissue volumes (P < .05). This is the first study to reveal increased retinal VVD in patients with relapsing-remitting MS. The measurements of VVD in the RVN and SVP were related to disability and visual function, which may be developed as image markers for tracking disease progression.

Optical Coherence Tomography Angiography Contributions in Classification of Nonproliferative Diabetic Retinopathy.

Introduction:To show the importance of optical coherence tomography (OCT) angiography imaging of superficial and deep capillary network in patients with non-proliferative diabetic retinopathy (NPDR), and to show the correlation between blood glucose level and changes in the foveal microvasculature.Methods:A cross-sectional study was performed on eyes with NPDR and healthy subjects using a highspeed 840-nm-wavelength spectral-domain optical coherence tomography instrument (RTVue XR Avanti; Optovue, Inc, Fremont, California, USA). Blood flow was detected using the split-spectrum amplitude-decorrelation angiography algorithm. A fully automated microstructural analysis of the foveal avascular zone (FAZ) and avascular surfaces was performed. Quantitative values from diabetic patients were compared with those of healthy subjects. Data about blood status in diabetic patients and healthy subjects were taken from patients’ medical history.Results:Size of both, FAZ and vascular dropout are significantly different between healthy patients and patients with NPDR. OCT angiography detected enlargement and distortion of the foveal avascular zone, retinal capillary dropout, and a higher number of vascular loops and microaneurysms. Sizes of FAZ and vascular dropout increase with the duration of disease. Central macular thickness (CMT) is not significantly different between healthy patients and patients with NPDR. A study has proven a positive correlation between the size of FAZ and the size of vascular dropout in superficial vascular plexus in patients that have DM over 10 years.Conclusion:A qualitative and quantitative OCT angiography approach to retinal vascular status can offer objective data on monitoring patients with non-proliferative diabetic retinopathy as well as indicate the progression of the disease.

Choroidal blood flow in glaucoma patients in conditions of ophthalmic hypertension and compensated intraocular pressure

Purpose. To evaluate changes in chorioretinal blood flow in the early postoperative period after non-penetrating deep sclerectomy (NPDS) in patients with primary open-angle glaucoma (POAG) and determine their relationship with the level of Goldman intraocular pressure (IOPg). Material and methods. The study included 36 patients with primary open-angle glaucoma of stage 1–2, with an IOP level above 21 mm Hg at the maximum hypotensive mode. All patients underwent glaucoma surgery (NPDS) by a single surgeon. IOP measurement was performed by dynamic bidirectional applanation using the Ocular Response Analyzer (Reichert Inc., USA). When evaluating the results, the Goldman IOP indicators (IOPg) were taken into account. The ophthalmic examination included optical coherence tomography of the optic disk and macular area, as well as assessment of the blood flow of these structures using optical coherence tomography in angio mode (OCTA) (RTVue XR Avanti, Optovue Inc., США). The thickness of the choroid was estimated using crossline protocols performed through the center of the fovea in the horizontal and vertical meridians. Results. Based on the assessment of changes in the indicators of ocular blood flow in the postoperative period, all patients were divided into 2 groups: group 1 – 28 patients (28 eyes) who showed improvement in OCTA after surgery, group 2 – 8 patients (8 eyes) who, according to OCTA data, showed no changes or decreased indicators of ocular blood flow after surgery. In patients of both groups, the level of IOPg before surgical treatment was comparable. On the 3rd day after NPDS IOPg in the group 1 decreased to 9.3 ± 1.2 mm Hg, while in group 2 hypotonia was detected (IOPg 3,6 ± 1,3 mm Hg, р = 0,001). All patients showed an increase in the thickness of the choroid in the central area and peripapillary after glaucoma surgery: in group 1 by 23 and 26 %, in group 2 by 48 and 62 %, respectively. In group 2 there was a significant increase in the large vessels caliber and the vascular membrane thickness as a whole to 115.4 % of the original. In group 1 patients, against the background of normalization of ophthalmotonus, there was a tendency to increase the capillary density of the superficial vascular plexus (from 40.9 ± 5.38 to 41.1 ± 3.56 %) and the deep vascular plexus (from 43.9 ± 6.1 to 44.7 ± 5.97 %). There was a positive trend of increasing capillary density in the radial peripapillary plexus (from 46.6 ± 8.9 to 47.2 ± 9.0 %). In patients of group 2, capillary density significantly decreased: from 39.9 ± 3.64 to 37.6 ± 2.48 % in the superficial vascular plexus and from 41.1 ± 4.72 to 38.7 ± 3.51 % in the deep vascular plexus. Conclusion. A decrease in the level of ophthalmotonus after NPDS was accompanied, in most cases, by a moderate increase in the thickness of the choroid and a tendency to improve blood flow in the retinal plexuses. Postoperative hypotension is characterized by dysregulation of choroidal blood flow, decompression violation of topographic relationships, which generally leads to the formation of choroidal effusion and vascular detachment.

Assessment of Retinal Microangiopathy in Chronic Kidney Disease Patients.

Introduction:Optical coherence tomography angiography (OCT-A) is a useful diagnostic tool for assessing eyes’ health in patients with chronic diseases, such as diabetes, hypertension, Parkinson’s disease and chronic kidney disease (CKD).Aim:To detect changes in macular structure and retinal vascular meshwork in the macular area and peripapillary in patients with chronic kidney disease (CKD).Methods:This cross-sectional study included 80 eyes of patients with CKD in stages 2, 3 or 4, who were followed-up in the Nephrology Clinic of University Clinical Center Sarajevo. All patients were categorized according to the stage of CKD. All patients were scanned by a high-speed 840-nm-wavelength spectral-domain optical coherence tomography instrument (RTVue XR Avanti; Optovue, Inc, Fremont, California, USA). Blood flow was detected using a split-spectrum amplitude-decorrelation angiography algorithm. A fully automated microstructural analysis of the foveal avascular zone (FAZ), FAZ perimeter, foveal vessel density in a 300-μm area around the FAZ (FD), nonflow area, flow index in superficial and deep vascular plexus, choriocapillary flow, vascular density, radial peripapillary capillary density was performed.Results:When comparing patients with CKD stage 2 and stage 3 there were no statistically significant changes in microvascular parameters on OCT angiography, as well as when comparing patients with CKD stage 3 and stage 4. But in the comparison between patients with less developed CKD (stage 2) and terminal CKD (stage 4) there was a significant difference between some microvascular parameters such as FAZ area, FAZ perimeter, choriocapillary flow.Conclusion:Many studies demonstrated that evaluation of the microvascular changes in different retinal layers using SS-OCTA may be considered as a key to assessing the systemic perfusion status. Evaluation of retinal microvasculature may ease the management and approach of patients with CKD, having in mind that the retinal and the kidney vascular network are, concerning structure, development and the function, very similar.

Keratosis Pilaris Rubra Totalis: Clinical and Histopathological Study with New insights

Background: Keratosis pilaris rubra (KPR) is a common but unrecognized follicular keratinizatioin. It is a common skin problem among Iraqi population and most cases were misdiagnosed as dermatitis as there are few reports in medical literature. Objective: To do full clinical and histopathological evaluation of KPR in Iraqi population. Patients and Methods: This is case descriptive, clinico-histopathological outpatient based study. It was done in the Center of Dermatology and Venereology, Baghdad Teaching Hospital, Medical City, Iraq during the period from March 2016 to October 2017. Sixty patients were enrolled in this study. History and dermatological examination were carried out for all patients. Skin biopsy was done for 10 patients for histopathological study using Hematoxylin and Eosin stain. Results: A total of the 60 patients were diagnosed as KPR during the study period. Thirty nine (65%) males and 21 (35%) females. The age at onset of disease ranged from since birth to 8 (2.9± 2.17) years . Facial involvement included the cheeks in 60 (100%) patients. Other sites of involvement included the arms where the lateral aspects involved in 60 (100%) patients and the medial aspect 11 (18.3%), thighs including the buttocks in 51 (85%), trunk 25 (41.6%), legs 22 (36.6%) and the neck 15 (25%).The rash was erythematous all over but most obvious on the sides of face presenting as red, rough face. Histopathological evaluation showed follicular plugging in (100%) with dilatation of both superficial and deep vascular plexus in (75%) of cases. Limitation: The main limitation of this study was the lack of follow up data related to the subject of the study. Conclusion: KPR is a common condition among Iraqi population and this study is the largest study carried out all over the world. As most areas of body are involved, the name keratosis pilaris rubra totalis is suggested.