Capillary Ring Research Articles

Macular retinal circulation in healthy eyes examined by optical coherence tomography angiography extended interscan time analysis.

To examine whether extended interscan time (IST) on optical coherence tomography angiography (OCTA) can detect slow retinal blood flow, which is undetectable on default IST, in the healthy macula. OCTA (OCT-A1, Canon Inc.) scanning of a macular area measuring 4 × 4 mm2 of 14 healthy eyes of 14 healthy volunteers with no history or evidence of systemic and macular diseases was performed. ISTs were set at 7.6 (IST7.6, default setting), 12.0 (IST12.0), and 20.6 msec (IST20.6). Ten OCTA images were acquired at each IST, and an averaged image was created. For each averaged OCTA image obtained at IST7.6, IST12.0, and IST20.6, we defined the area surrounded by the innermost capillary ring as the foveal avascular zone (FAZ). We qualitatively evaluated the delineation of the capillaries consisting of the FAZ and quantitatively measured the FAZ area at each IST. Extensions from IST7.6 to IST12.0 and IST20.6 could newly delineated retinal capillaries that were undetectable at the default IST; new capillaries were detected in 10 (71%) eyes at IST12.0 and 11 (78%) eyes at IST20.0. The FAZ areas were 0.334 ± 0.137 mm2, 0.320 ± 0.132 mm2, and 0.319 ± 0.129 mm2 for IST7.6, IST12.0, and IST20.0, respectively; the FAZ areas at IST12.0 and IST20.0 were significantly decreased compared with that at IST7.6 (p = 0.004 and 0.002, respectively). In OCTA for healthy participants, extensions of the ISTs newly detected retinal capillaries with slow blood flow around FAZ. The FAZ shapes varied with different ISTs. Thus, the blood flow dynamics are not physiologically uniform around FAZ. Compared with conventional OCTA, this protocol enables a more detailed evaluation of retinal circulation and provides a better understanding of the physiological circulatory status of the healthy retina, and may enable the assessment of circulation in the very early stages in diseased eyes.

Vasculature in the mouse colon and spatial relationships with the enteric nervous system, glia, and immune cells.

The distribution, morphology, and innervation of vasculature in different mouse colonic segments and layers, as well as spatial relationships of the vasculature with the enteric plexuses, glia, and macrophages are far from being complete. The vessels in the adult mouse colon were stained by the cardiovascular perfusion of wheat germ agglutinin (WGA)-Alexa Fluor 448 and by CD31 immunoreactivity. Nerve fibers, enteric glia, and macrophages were immunostained in the WGA-perfused colon. The blood vessels entered from the mesentery to the submucosa and branched into the capillary networks in the mucosa and muscularis externa. The capillary net formed anastomosed rings at the orifices of mucosa crypts, and the capillary rings surrounded the crypts individually in the proximal colon and more than two crypts in the distal colon. Microvessels in the muscularis externa with myenteric plexus were less dense than in the mucosa and formed loops. In the circular smooth muscle layer, microvessels were distributed in the proximal, but not the distal colon. Capillaries did not enter the enteric ganglia. There were no significant differences in microvascular volume per tissue volume between the proximal and distal colon either in the mucosa or muscularis externa containing the myenteric plexus. PGP9.5-, tyrosine hydroxylase-, and calcitonin gene-related peptide (CGRP)-immunoreactive nerve fibers were distributed along the vessels in the submucosa. In the mucosa, PGP9.5-, CGRP-, and vasoactive intestinal peptide (VIP)-immunoreactive nerves terminated close to the capillary rings, while cells and processes labeled by S100B and glial fibrillary acidic protein were distributed mainly in the lamina propria and lower portion of the mucosa. Dense Iba1 immunoreactive macrophages were closely adjacent to the mucosal capillary rings. There were a few macrophages, but no glia in apposition to microvessels in the submucosa and muscularis externa. In conclusion, in the mouse colon, (1) the differences in vasculature between the proximal and distal colon were associated with the morphology, but not the microvascular amount per tissue volume in the mucosa and muscle layers; (2) the colonic mucosa contained significantly more microvessels than the muscularis externa; and (3) there were more CGRP and VIP nerve fibers found close to microvessels in the mucosa and submucosa than in the muscle layers.

Design of highly sensitive biosensors using hollow-core microstructured fibers for plasma sensing in aids with human metabolism.

Detection of low index liquid analytes in real-time, in-situ, and with high accuracy is of great importance in various scientific fields, particularly in medicine and biology. Accurate detection of plasma concentration in blood samples is one of the most significant usages of biosensors in medicine. In this paper, we report a highly sensitive biosensor using hollow core microstructure optical fibers (HC-MOFs) to detect low index liquid analytes with a particular focus on detection of plasma concentration in blood samples. We demonstrate how variations in plasma concentration in blood can change transmission spectra of the HC-MOF due to the photonic bandgap mechanism. We use the finite element approach to explore how the biosensor's performance depends on the number of capillary rings encircling the hollow core of the fibre. An average spectral and amplitude sensitivity of 8928.57nm/RIU and 1.21 dB/RIU is reported for the optimized design of HC-MOF for five capillary rings with a refractive index detection range of 1.333 to 1.3385 for different ratios of plasma in blood serum. The proposed biosensor can have potential application in liquid analyte detection in medicine, chemistry, and biology where real-time and accurate data about liquid analytes are necessary for human metabolism.

High-Throughput DNA Analysis Platform Based on an Optofluidic Ring Resonator Laser

We demonstrate an optofluidic laser using DNA microdroplets, an intercalating dye, and a glass capillary ring resonator. Only the target DNA emits the laser signal, while the non-target DNA, including those with single-base mismatches, exhibits zero optical signals. Subsequently, a single laser emission detected within a few milliseconds can distinguish the target DNA from others, allowing for truly digital DNA sequence analysis from an optical point of view. In addition, the microdroplets could be individually investigated using our optofluidic system. These advances in laser-based DNA analysis make our proposed scheme a promising, rapid, and high-throughput DNA sequence analysis platform.

Strong circular dichroism for the HE11 mode in twisted single-ring hollow-core photonic crystal fiber: erratum

Recent work has revealed that the dispersion relation, given in Optica 5, 1315 (2018)10.1364/OPTICA.5.001315, for helical Bloch modes in a ring of capillaries surrounding a central hollow core, is incorrect. Here we correct this error and provide a revised version of Fig. 2. The overall conclusions of the original paper are unaffected.

Prevention of trichinellosis on fur farms

The purpose of the research is analysing a complex of veterinary and sanitary preventive measures against trichinellosis on fur farms.Materials and methods. The system of measures against trichinellosis is based on creating conditions on fur farms that are aimed at prevention of the invasion, and includes occasional immunological screening of animals, examination of dead animals for trichinellosis and observation of veterinary, sanitary and zootechnical requirements for animal management.Results and discussion. The sero-epizootic monitoring methods of elderly animals implemented on farms based on ELISA and Capillary Ring Precipitin Test allows us to identify infected animals and exclude them from the technology system of maintenance and breeding. The general situation of trichinellosis can be determined by results of studies by a compression or enzyme methods of animal carcasses during the period of mass slaughter for fur.

The Role of Discrete Capillary Rings in Mass Transfer From the Surface of a Drying Capillary Porous Medium

The mass exchange between the surface of a model capillary porous medium and the adjacent gas-side boundary layer is studied in the limiting condition of isothermal, slow drying. In order to quantify the role and significance of liquid films in the mass exchange process, three-dimensional pore network Monte Carlo simulations are carried out systematically in the presence and absence of discrete capillary rings. The pore network simulations performed with capillary rings show a noticeable delay in transition from the capillary-supported regime to the diffusion-controlled regime. These simulation results differ significantly from the predictions of classical pore network models without liquid films, and they appear to be more consistent with the experiments conducted with real porous systems. As compared to classical pore network models, the pore network model with rings seems to predict favorably the spatiotemporal evolution of wet and dry patches at the medium surface as well as of their relative contributions to the net mass exchange rate. This is apparent when the analytical solution of the commonly used Schlünder’s model is examined against the numerical simulations conducted using classical and ring pore network models.

Butt-Coupling of 4.5 μm Quantum Cascade Lasers to Silica Hollow Core Anti-Resonant Fibers

We report on experimental characterization of butt-coupling between a quantum cascade laser operating around the wavelength of 4.5 μm and a silica hollow core anti-resonant fiber. The used fiber has a single ring of non-touching capillaries surrounding a 42.5 μm dimeter air core and a mid-infrared transmission window in the wavelength range of 2.8 to 4.7 μm. A lens-less butt-coupling interconnection is established and coupling efficiency of 22% is achieved with over 100 mW of power at the fiber output. Bending losses in this test-bed system are verified depending on radius with the loss remaining below 1 dB/m for 20 mm loops, while bend losses exceeding 10 dB/m are observed when the fiber is bent down to a 5-mm radius. The presented coupling dramatically improves the output beam quality of the quantum cascade laser with a measured NA = 0.45. The beam at the fiber output has a circular shape, measured M <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> = 1.04 and uniform numerical aperture of NA = 0.13. Together with the hollow core fiber geometry, the proposed system would be suitable for simple implementations of absorption spectroscopy of popular atmospheric agents, like N <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O.

Fusion Splicing of Silica Hollow Core Anti-Resonant Fibers With Polarization Maintaining Fibers

Fusion splicing of solid-core microstructured silica fibers has been one of the key enablers which opened practical applications of these structures in ultrafast light sources or fiber-based sensors. Anti-resonant hollow core fibers are special in this context, because their optical properties critically depend on single-micron or sub-micron thin wall membranes. This corresponds to high thermal isolation of their cladding structure and makes thermal processing of these fibers challenging. We investigate fusion splicing feasibility of a single capillary ring anti-resonant hollow core fiber made of silica glass. We begin by splicing pairs consisting of standard single mode and hollow core fibers, followed by pairs of polarization maintaining and hollow core fibers. Splice loss is determined within the 1450-2000 nm transmission window of the fiber at around 1-2 dB, depending on wavelength along the transmission window, in the transmission direction from the step index fiber into the hollow core fiber. Maintenance of polarization is verified and polarization extinction ratio of no less than 10 dB is recorded for the ARF spliced with a polarization maintaining fiber. Mechanical robustness of the fabricated splices is verified with standard pull tests returning damage thresholds of 140 g (32 kpsi) and 100 g (24 kpsi) for hollow core fibers spliced to single mode and polarization maintaining fibers, respectively.

The relationship between perifoveal capillary ring alterations and visual acuity in diabetic retinopathy

Background/Aim. The relationship between the foveal avascular zone (FAV) and visual acuity (VA) in retinal dis-eases remains a matter of discussion. The aim of this study was to determine the impact of diabetic macular ischemia (DMI) on VA through the analysis of the perifoveal capillary network in various stages of diabetic retinopathy - DR (non-proliferative diabetic retinopathy ? NPDR and proliferative diabetic retinopathy ? PDR). Methods. Qualitative and quantitative analysis of 143 angiograms of patients with different stages of DR was performed. The degree of macular ischemia was assessed by the analysis of 2 parameters: perifoveal capillary ring, ie, the FAZ outline irregularity, and capillary loss. Finally, a comparison was made between the degree of macular ischemia with the best-corrected VA, depending on macular thickness. Results. In the eyes with mild and moderate NPDR, without significant macular thickening, no statistically significant decrease in VA caused by macular ischemia was noticed (p = 0.81). Opposite, in a subgroup with severe NPDR and PDR, without significant macular thickening, a statistically significant difference was presented among eyes with moderate and severe macular ischemia compared to eyes with lower grades of macular ischemia (p = 0.021 and p = 0.018, respectively). In the eyes with moderate NPDR and mild macular ischemia, the increase in macular thickness resulted in a statistically insignificant decrease in VA compared to eyes with a normal macular thickness (p = 0.088). However, in the eyes with severe NPDR, every pathological increase in macular thickness caused a statistically significant decrease in VA, regardless of the degree of macular ischemia (p = 0.018?0.040). A similar relationship was also found in the eyes with PDR (p = 0.017?0.042). In the eyes with a statistically significant decrease in VA, most of the examined eyes (98%) had the FAZ outline irregularity in the nasal perifoveal subfield. Conclusion. In the absence of significant macular thickening, the destruction of one-half of the perifoveal capillary network, or greater, is associated with reduced VA. The location of macular ischemic changes in the nasal parts of the perifoveal capillary ring plays a crucial role in its effects on visual function.

Correlation between macular edema recurrence and macular capillary network destruction in branch retinal vein occlusion

BackgroundThe aim of this study was to evaluate the correlation between changes in the macular capillary network and macular edema (ME) recurrence with branch retinal vein occlusion (BRVO) using swept-source optical coherence tomography angiography (SS-OCTA).MethodsWe reviewed the data for 43 patients with treatment-naïve ME associated with BRVO. Patients who received intravitreal bevacizumab injection were divided into two groups based on ME recurrence at 6 months after edema resolution. The perifoveal capillary morphology and the macular capillary vessel density (VD) were retrospectively analyzed using en face SS-OCTA after ME resolution.ResultsThe perifoveal capillary ring loss in the superficial capillary plexus (SCP) and deep capillary plexus (DCP) was more common in the ME recurrence group (n = 22) than in the no ME recurrence group (p = 0.047 and p = 0.002). Relative to the findings in the no ME recurrence groups, the destruction of the perifoveal capillary ring was more severe in the DCP (30.0° vs 87.3°, p = 0.001) than in the SCP (17.3° vs 69.5°, p = 0.006) in the ME recurrence group. The hemi-VD disparity between the affected and the unaffected areas in the SCP and DCP showed significant differences (p = 0.031 and p = 0.017), while macular VD showed no differences between the groups.ConclusionsDestruction of the perifoveal capillary ring and hemi-VD disparity could be related to ME recurrence in BRVO. Therefore, these factors may be helpful in predicting ME recurrence.

Instability of finite-amplitude gravity–capillary progressive ring waves by an oscillating surface-piercing body

We investigate the instability of finite-amplitude progressive ring waves in deep water, which are radiated by the time-periodic oscillation of a half-submerged sphere (with radius ), under the influence of gravity and surface tension. We use direct numerical simulations of fully nonlinear wave–body interactions to quantify the temporal–spatial evolution of the base and perturbed outgoing ring wave fields, from which the stability of ring waves is analysed. The numerical simulation is based on a mixed Euler–Lagrangian quadratic boundary-element method and accounts for fully nonlinear wave–wave and wave–body interactions in the context of potential flow. We find that the progressive gravity–capillary ring waves (with frequency ) become unstable to (small-amplitude) radial cross-wave disturbances when the body-motion parameter exceeds the threshold value , where is the amplitude of body oscillation and is the wavenumber of the ring wave at subharmonic frequency . The predicted from nonlinear simulations under the assumption of ideal fluid, which decreases with increasing , is generally smaller than the experimental measurement of Tatsuno et al. (Rep. Res. Inst. Appl. Mech. Kyushu University, vol. 17, 1969, pp. 195–215) by approximately 50 %. When the viscous effects in body-surface and free-surface boundary layers are taken into account, the predicted matches the experimental data excellently. The unstable modes are characterized as the progressive radial cross-waves at the subharmonic frequency ( ) with the growth rates generally increasing with . The maximum growth rate is achieved for the cross-wave mode with the azimuthal wavenumber . These distinctive features of instability obtained in numerical simulations are consistent with the experimental observations. From the comparison with the weakly nonlinear analysis of Shen & Liu (J. Fluid Mech., vol. 869, 2019, pp. 439–467), it is found that inclusion of finite-amplitude ring wave effects generally reduces the growth rate of unstable modes but has an insignificant influence on the shape of unstable modes and the value of . Moreover, for moderately steep ring waves, nonlinear interactions of a few unstable modes can excite broadbanded unstable subharmonic cross-wave modes, leading to the formation/observation of distinctive non-axisymmetric wave patterns during long-time evolutions.

Topographic Distribution of Contractile Protein in the Human Macular Microvasculature.

We studied the topographic distribution of contractile protein in different orders of the human macular microvasculature to further understanding of the sites for capillary blood flow regulation. Nine donor eyes from eight donors were cannulated at the central retinal artery and perfusion labeled for alpha smooth muscle actin (αSMA) and filamentous actin (F-actin). Confocal images were collected from the macula region, viewed, projected, and converted to a 255 grayscale for measurements. The mean intensity was measured for macular arterioles, venules, and capillary segments. The diameter of each vessel segment measured was recorded. The normalized mean intensity values from all images were ranked according to vessel types and size with a total of nine categories. F-actin was present throughout the macular microvasculature whereas αSMA labeling showed variations. Overall, αSMA has a more prominent presence in the macular arterioles than in the macular capillaries and venules, and αSMA strongly labeled the smaller macular arterioles. Some capillaries also labeled positive for αSMA, including some of the capillaries in the innermost capillary ring surrounding the foveola. It was weakly present in the capillaries on the venous side and larger venules. In the larger macular arterioles closer to 100 μm in diameter, αSMA labeling was weakly present and not as ubiquitous as in the smaller arterioles. Nonuniform distribution of contractile proteins in the different types, orders, and sizes of macular microvasculature indicates that these vessels may have different contractile capability and roles in macular flow regulation.

Strong circular dichroism for the HE11 mode in twisted single-ring hollow-core photonic crystal fiber

We report a series of experimental, analytical, and numerical studies demonstrating strong circular dichroism for the HE11-like core mode in helically twisted hollow-core single-ring photonic crystal fiber (SR-PCF), formed by spinning the preform during fiber drawing. In the SR-PCFs studied, the hollow core is surrounded by a single ring of nontouching capillaries. Coupling between these capillaries results in the formation of helical Bloch modes carrying orbital angular momentum. When twisted, strong circular birefringence appears in the ring, so that coupling to the core mode is possible for only one circular polarization state. The result is a SR-PCF that acts as a circular polarizer, offering 1.4 dB/m for the low-loss polarization state and 9.7 dB/m for the high-loss state over a 25 nm band centered at 1593 nm wavelength. In addition, we report for the first time that the vector fields of the helical Bloch modes are perfectly periodic when evaluated in cylindrical coordinates. Such fibers have many potential applications, such as generating circularly polarized light in gas-filled SR-PCF and realizing polarizing elements in the deep and vacuum ultraviolet.

Effect of Nested Elements on Avoided Crossing between the Higher-Order Core Modes and the Air-Capillary Modes in Hollow-Core Antiresonant Optical Fibers

Optimal suppression of higher-order modes (HOMs) in hollow-core antiresonant fibers comprising a single ring of thin-walled capillaries was previously studied, and can be achieved when the condition on the capillary-to-core diameter ratio is satisfied (d/D≈0.68). Here we report on the conditions for maximizing the leakage losses of HOMs in hollow-core nested antiresonant node-less fibers, while preserving low confinement loss for the fundamental mode. Using an analytical model based on coupled capillary waveguides, as well as full-vector finite element modeling, we show that optimal d/D value leading to high leakage losses of HOMs, is strongly correlated to the size of nested capillaries. We also show that extremely high value of degree of HOM suppression (∼1200) at the resonant coupling is almost unchanged on a wide range of nested capillary diameter dNested values. These results therefore suggest the possibility of designing antiresonant fibers with nested elements, which show optimal guiding performances in terms of the HOM loss compared to that of the fundamental mode, for clearly defined paired values of the ratios dNested/d and d/D. These can also tend towards a single-mode behavior only when the dimensionless parameter dNested/d is less than 0.30, with identical wall thicknesses for all of the capillaries.

Higher-order mode suppression in twisted single-ring hollow-core photonic crystal fibers.

A hollow-core single-ring photonic crystal fiber (SR-PCF) consists of a ring of capillaries arranged around a central hollow core. Spinning the preform during drawing introduces a continuous helical twist, offering a novel means of controlling the modal properties of hollow-core SR-PCF. For example, twisting geometrically increases the effective axial propagation constant of the LP01-like modes of the capillaries, providing a means of optimizing the suppression of HOMs, which occurs when the LP11-like core mode phase-matches to the LP01-like modes of the surrounding capillaries. (In a straight fiber, optimum suppression occurs for a capillary-to-core diameter ratio d/D=0.682.) Twisting also introduces circular birefringence (to be studied in a future Letter) and has a remarkable effect on the transverse intensity profiles of the higher-order core modes, forcing the two-lobed LP11-like mode in the untwisted fiber to become three-fold symmetric in the twisted case. These phenomena are explored by means of extensive numerical modeling, an analytical model, and a series of experiments. Prism-assisted side-coupling is used to measure the losses, refractive indices, and near-field patterns of individual fiber modes in both the straight and twisted cases.

Hollow-core microstructured ‘revolver’ fibre for the UV spectral range

We report the first silica-based hollow-core microstructured fibre for the UV spectral range, with a reflective cladding formed by a single ring of capillaries. The optical loss in the fibre at a wavelength of is . We demonstrate distinctions between the propagation of high-order modes and the fundamental mode of the hollow core of a ‘revolver’ fibre with noncontacting cladding capillaries and examine the effect of multimode excitation on the transmission bandwidth of the fibre. Based on experimental data and numerical simulation results, we formulate recommendations how to reduce the level of losses and extend transmission bands in a hollow-core revolver fibre in the UV spectral range.

EVALUATION OF AN OPTIMIZING PROTOCOL FOR FABRICATING A SCAFFOLD DERIVED FROM PORCINE SKELETAL MUSCLE EXTRACELLULAR MATRIX

To explore an optimized protocol of decellularization to fabricate an ideal scaffold derived from porcine skeletal muscle acellular matrix. Serial-step protocol of homogenating-milling-detergent method was used to fabricate decellularized porcine muscle tissue (DPMT) derived from native porcine skeletal muscle tissue from adult pig waist. Histological method was used to assess the effects of decellularization and degreasing. Sirius red staining was used to analyze collagen components. Scanning electron microscopy, BCA assay, and PicoGreen assay were used to evaluate the ultrastructure, total protein content, and DNA content in DPMT. The adipose derived stem cells (ADSCs), NIH3T3 cells, and human umbilical vein endothelial cells (HUVECs) were cultured in extraction liquor of DPMT in different concentrations for 1, 3, and 5 days, then the relative growth rate was calculated with cell counting kit 8 to assess the toxicity in vitro. Live/dead cell staining was used to evaluate the cytocompatibility by seeding HUVECs on the surface of DPMT and co-cultured in vitro for 3 days. For in vivo test, DPMT was subcutaneously implanted at dorsal site of male specific-pathogen free Sprague Dawley rats and harvested after 3, 7, 14, and 28 days. Gross obersvation was done and transverse diameter of remained DPMT in vivo was determined. HE staining and immunohistochemical staining of CD31 were used to assess inflammatory response and new capillary rings formation. Decellularization of the porcine skeletal muscle tissue by homogenating-milling-detergent serial steps protocol was effective, time-saving, and simple, which could be finished within only 1 day. The decellularizarion and degreasing effect of DPMT was complete. The main component of DPMT was collagen type I and type IV. The DNA content in DPMT was (15.902±1.392) ng/mg dry weight, the total protein content was 68.94% of DPMT dry weight, which was significantly less than those of fresh skeletal muscle tissue[(140.727±10.422) ng/mg and 93.14%] (P<0.05). The microstructure of DPMT was homogeneous and porous. The result of cytocompatibility revealed that the cytotoxicity of DPMT was 0-1 grade, and HUVECs could stably grow on DPMT. In vivo study revealed DPMT could almost maintain its structural integrity at 14 days and it degraded completely at 28 days after implantation. The inflammatory response peaked at 3 days after implantation, and reduced obviously at 7 days. Difference was significant in the number of inflammatory cells between 2 time points (P<0.05). Neovascularization was observed at 7 days after implantation and the number of new vessels increased at 14 days, showing significant difference between at 7 and 14 days (P<0.05). The homogenating-milling-detergent serial-steps protocol is effective, time-saving, and reproducible. The DPMT reveals to be cell and lipid free, with highly preserved protein component. DPMT has good biocompatibility both in vitro and in vivo and may also have potential in promoting neovascularization.

Propagation of femtosecond pulses in a hollow-core revolver fibre

We have studied for the first time the propagation of femtosecond pulses through an optical fibre with an air-filled hollow core and a cladding in the form of one ring of noncontacting cylindrical capillaries for high-power radiation transmission in the telecom range. Numerical analysis results demonstrate that the parameters of the fibre enable radiation transmission in the form of megawatt-power Raman solitons through up to a length of the fibre and tuning of the emission wavelength over . We have experimentally demonstrated femtosecond pulse transmission through fibres up to in length in the linear propagation regime, without distortions of the pulse spectrum, with a dispersion-induced temporal pulse broadening within 20 %.

Factors correlated with the resolution of macular oedema after one dose injection of intravitreal triamcinolone acetonide treatment in branch retinal vein occlusion.

ObjectiveTo investigate the predictive baseline factors for a successful outcome following one dose of intravitreal triamcinolone acetonide (IVTA) in patients with macular oedema (ME) caused by branch retinal vein occlusion (BRVO).MethodsThis retrospective study enrolled patients with ME (macular retinal thickness [MRT] ≥ 300 µm) due to BRVO who still had ME 3 months after grid laser photocoagulation. Patients were divided according to treatment into an IVTA group and a laser-only group. The resolution of ME was documented at months 3 and 6.ResultsA total of 154 eyes with ME were investigated: IVTA group (90 eyes) and laser-only group (64 eyes). Predictive factors for successful IVTA treatment were younger age, shorter duration of ME, initial onset ME, accompanied by serous retinal detachment, few concomitant systemic diseases and nonischaemic BRVO. A broken foveal capillary ring was related to a poor treatment outcome. Eyes with cystoid spaces in the outer plexiform layer were more likely to have a good treatment response.ConclusionIVTA is effective for resolving ME due to BRVO after grid laser photocoagulation treatment.