Drug combination of topical ripasudil and brimonidine enhances neuroprotection in a mouse model of optic nerve injury.

PURPOSE: To determine whether combination of topical ripasudil and brimonidine has more effective neuroprotection on retinal ganglion cells (RGCs) following injury to axons composing the optic nerve. METHODS: Topical ripasudil, brimonidine, or mixture of both drugs were administered to adult mice after optic nerve injury (ONI). The influence of drug conditions on RGC health were evaluated by the quantifications of surviving RGCs, phosphorylated p38 mitogen-activated protein kinase (phospho-p38), and expressions of trophic factors and proinflammatory mediators in the retina. RESULTS: Topical ripasudil and brimonidine suppressed ONI-induced RGC death respectively, and mixture of both drugs further stimulated RGC survival. Topical ripasudil and brimonidine suppressed ONI-induced phospho-p38 in the whole retina. In addition, topical ripasudil suppressed expression levels of TNFα, IL-1ß and monocyte chemotactic protein-1 (MCP-1), whereas topical brimonidine increased the expression level of basic fibroblast growth factor (bFGF). CONCLUSIONS: Combination of topical ripasudil and brimonidine may enhance RGC protection by modulating multiple signaling pathways in the retina.

Percutaneous intravascular micro-axial blood pump: current state and perspective from engineering view.

The utilization of a minimally invasively placed catheter-mounted intravascular micro-axial flow blood pump (IMFBP) is increasing in the population with advanced heart failure. The current development of IMFBPs dates back around the 1990s, namely the Hemopump with a wire-drive system and the Valvopump with a direct-drive system. The wire-drive IMFBPs can use a brushless motor in an external console unit to transmit rotational force through the drive wire rotating the impeller inside the body. The direct-drive IMFBPs require an ultra-miniature and high-power brushless motor. Additionally, the direct-drive system necessitates a mechanism to protect against blood immersion into the motor. Therefore, the direct-drive IMFBPs can be categorized into two types of devices: those with seal mechanisms or those with sealless mechanisms using magnetically coupling. The IMFBPs can be classified into two groups depending on their purpose. One group is for cardiogenic shock following a heart attack or for use in high-risk percutaneous coronary intervention (PCI), and the other group serves the purpose of acute decompensated heart failure. Both direct-drive IMFBPs and wire-drive IMFBPs have their own advantages and disadvantages, and efforts are being made to develop and improve, and clinically implement them, leveraging their own strengths. In addition, there is a possibility that innovative new devices may be invented. For researchers in the field of artificial heart development, IMFBPs offer a new area of research and development, providing a novel treatment option for severe heart failure.

Development and initial performance of a miniature axial flow blood pump using magnetic fluid shaft seal.

In this study, we developed a new catheter-mounted micro-axial flow blood pump (MFBP) using a new miniature magnetic fluid shaft seal (MFSS). The prototype of the catheter-mounted MFBP had a maximum diameter of 8 mm and a length of 50 mm. The new MFSS composed a neodymium magnet ring, an iron ring, and a magnetic fluid particularly designed for the MFSS. The new MFSS had outer and inner diameters of 4.0 mm and 2.6 mm, respectively, and a length of 3.0 mm. The sealing pressure of the MFSS was calculated to be 432 mmHg using FEM (Finite Element Method) result; therefore, the MFSS had sufficient sealing pressure for the catheter-mounted MFBP. The friction loss of the MFSS included the friction owing to the viscosity of the magnetic fluid and the magnetic force between the iron ring and ring magnet. The total friction loss of the MFSS was 0.08-0.09 W in the pump operational speed range from 22,000 to 35,000 rpm. From the in vitro experimental results, the catheter-mounted MFBP using the MFSS had a pump output of 3 L/min. against a differential pressure of 60 mmHg, and the pump characteristics of the MFBP were almost the same as those of Impella 5.0.

Binocular metamorphopsia in patients with branch retinal vein occlusion: a multi-center study.

PURPOSE: The pathology of branch retinal vein occlusion (BRVO), a retinal circulatory disease, is related to monocular metamorphopsia-related vision impairment of the affected eyes, but the association of binocular metamorphopsia in such patients is unclear. This study aimed to examine the frequency of binocular metamorphopsia and its association with the clinical characteristics of patients with BRVO. METHODS: A total of 87 patients who were treated for BRVO-associated macular edema (ME) were included in this study. At baseline and 1 and 3 months after the initiation of anti-vascular endothelial growth factor (VEGF) treatment, we quantified metamorphopsia in the affected eyes and binocular metamorphopsia using the M-CHARTS® diagnostic tool. RESULTS: At baseline, 53 and 7 patients had metamorphopsia in the affected eyes and binocular metamorphopsia, respectively. Although the visual acuity improved significantly after the initiation of anti-VEGF treatment, the mean M-CHARTS score in the affected eyes did not change from the baseline score. At 3 months, 9 patients showed binocular metamorphopsia; it was significantly associated with metamorphopsia in the affected eyes with a 95% confidence interval of 0.021-0.122 (ß = 0.306, p = 0.006). CONCLUSION: Metamorphopsia in the affected eyes can cause binocular metamorphopsia in patients with BRVO-ME.

Ten-year changes in visual acuity at baseline and at 2 years after treatment in a Japanese population with age-related macular degeneration.

PURPOSE: We investigated 10-year changes in baseline best-corrected visual acuity (BCVA), as well as functional and anatomical changes at 1 and 2 years after initial treatment, in eyes with treatment-naïve neovascular age-related macular degeneration (nAMD). METHODS: This retrospective, multicenter, case series reviewed patients with treatment-naïve nAMD who underwent initial treatment from 2006 to 2015, using photodynamic therapy (PDT), anti-vascular endothelial growth factor (VEGF), or a combination of PDT and anti-VEGF. BCVA and central retinal subfield thickness (CRST), were measured at baseline and at 1 or 2 years of follow-up. RESULTS: In total, 3096 eyes of 3096 patients were included from 14 hospitals. Mean BCVA at baseline became significantly better over the 10-year study period (P < 0.001). BCVA at 1 year significantly improved from baseline in patients who underwent initial treatment from 2009 to 2015 (P = 0.001, 2009; P = 0.004, 2010; P = 0.01, 2011; P < 0.001, 2012-2015). BCVA at 2 years significantly improved from baseline in patients who underwent initial treatment from 2012 to 2015 (P < 0.001, 2012; P < 0.001, 2013-2015). CRST at 1 year decreased significantly from CRST at baseline, each year from 2006 to 2015 (P < 0.001, 2006-2015). CRST at 2 years decreased significantly from CRST at baseline, each year from 2006 to 2015 (P = 0.03, 2006; P < 0.001, 2007-2015). CONCLUSION: Baseline BCVA with treatment-naïve nAMD tended to become better during the study period. BCVA at 1 year improved in the era of anti-VEGF; BCVA at 2 years improved in patients who underwent initial treatment in 2012 or later; and CRST decreased in each year during the study period.

In vitro performance of trans-valve left ventricular assist device installed at aortic valve position.

In this study, we developed a trans-valve left ventricular assist device (LVAD) that unites a rear-impeller axial-flow blood pump (AFBP) and a polymer membrane valve placed at the aortic valve position. The diameter and length of the rear impeller AFBP was 12 and 63 mm, respectively. The polymer membrane valve was similar to the jelly-fish valve consisting of a valve leaflet made of silicone rubber (thickness 0.5 mm), valve ring (diameter: 25 mm), and valve spokes. The trans-valve LVAD was examined in a mock circulation. An implantable pulsatile flow (PF) VAD was connected to an atrial reservoir to simulate the left ventricle (LV), and the Hall valve was worn in the inflow port, and the trans-valve LVAD was placed in the outflow port as an outflow valve. When the motor rotational speed increased to 26 400 rpm, the mean aortic flow increased from 4.2 to 5.3 L/min, mean aortic pressure increased from 83.4 to 100 mm Hg, and mean motor current of the implantable PF VAD decreased from 1.18 to 0.94 A (unloading effect on LV -21%). The energy equivalent pressure increased from 85.2 to 102 mm Hg, and surplus hemodynamic energy (SHE) decreased by -15.4% from the baseline. In conclusion, the trans-valve LVAD has an advantage of preserving pulsatility without any complicated mechanism and is a novel and promising LV support device.

Changes of choroidal structure and circulation after water drinking test in normal eyes.

PURPOSE: To determine whether water drinking test (WDT) alters choroidal structure using binarization of enhanced depth imaging optical coherence tomographic (EDI-OCT) images. METHODS: We performed a prospective study of 57 eyes of 57 normal subjects. The intraocular pressure (IOP), EDI-OCT images, and laser speckle flowgraphic images were recorded at baseline, and at 15, 30, 45, and 120 min after the WDT. The EDI-OCT images were converted to binary images using ImageJ software, and we examined luminal area, interstitial area, whole choroidal area, the ratio of luminal area to whole choroidal area (L/W ratio), subfoveal choroidal thickness (SCT), and central retinal thickness (CRT). RESULTS: The luminal area, L/W ratio, whole choroidal area, and IOP were significantly increased 30 min after water drinking; levels returned to the baseline at 120 min. No significant changes were found in the CRT and interstitial area. The fluctuations in the SCT after water intake were significantly correlated with those in the L/W ratio and luminal area but not with those of the interstitial area. The choroidal blood flow velocity was significantly decreased at 30 min. Fluctuations in the luminal area, L/W ratio, and whole choroidal area were significantly correlated with IOP fluctuations. CONCLUSIONS: The changes in the SCT after water drinking were mainly due to the changes in the choroidal vascular space. Dilatations of the choroidal vessels after water drinking may lead to choroidal thickening and subsequent IOP elevation. These findings should be considered in the evaluation of choroidal structure in patients with retinal disease.

Development of rear-impeller axial flow blood pump for realization of axial flow blood pump installed at aortic valve position.

In this study, rear-impeller axial flow blood pumps (RIAFBP) were developed to realize a trans-valve axial ventricular assist device (VAD) which consists of the latter blood pump and a polymer monomembrane aortic valve, such as the jellyfish valve. The motor of the RIAFBP is installed in the left ventricle, and its impeller is placed at the aortic valve position. In the prototype RIAFBP, the rotation of the motor is sustained by polyethylene bushings. The RIAFBP has a length of 50 mm and diameter of 19.6 mm. The miniature RIAFBP has the same construction as that of the prototype; however, it employs a ceramic bearing and fin bearing to improve endurance and to reduce blood stagnation. The miniature RIAFBP has a length of 63 mm and diameter of 12 mm. Both RIAFBPs were examined by an in vitro experiment using a 33% glycerin solution. The prototype RIAFBP achieved a maximum pump outflow of 8.5 L/min against a pump head of 100 mm Hg at a rotational speed of 12 000 rpm. The miniature RIAFBP achieved 7 L/min against a pump head of 70 mm Hg at a rotational speed of 21 600 rpm. In conclusion, the miniature RIAFBP has enough pump performance to realize the trans-valve axial VAD.

CORRELATIONS BETWEEN CHOROIDAL STRUCTURES AND VISUAL FUNCTIONS IN EYES WITH RETINITIS PIGMENTOSA.

PURPOSE: To investigate the choroidal structures in the enhanced depth imaging optical coherence tomographic images in eyes with retinitis pigmentosa (RP) and to determine correlations between the choroidal structures and visual functions. METHODS: The enhanced depth imaging optical coherence tomographic images of 100 eyes with typical RP and 60 age-, sex-, and axial length-matched normal eyes were binarized using ImageJ. The cross-sectional luminal and stromal areas of the inner and outer subfoveal choroid of 1,500-µm width were measured. The inner choroid included the choriocapillaris and medium vessel layer, and the outer choroid included the larger vessel layer. RESULTS: In the inner choroid, the luminal area and the ratio of luminal/total choroidal area (L/C ratio) were significantly smaller in RP than in controls (P = 0.010, P < 0.001, respectively), whereas the stromal area was not significantly different (P = 0.114). The inner choroidal L/C ratio was significantly correlated with the best-corrected visual acuity, mean deviation, foveal sensitivity, width of the ellipsoid zone, and central foveal thickness in RP after adjusting for the axial length, age, and sex (all P < 0.005). CONCLUSION: The significant correlations between the inner choroidal structures and the visual functions and retinal structures indicate that the choroidal structures are altered in association with the progression of RP.

TRAFFIC ACCIDENT-RELATED OPEN GLOBE INJURIES.

PURPOSE: To evaluate the clinical characteristics and visual outcomes of patients with traffic accident-related open globe injuries, and to examine preoperative factors influencing the visual prognosis after pars plana vitrectomy, as compared with common open globe injuries. METHODS: Patients with open globe injuries, who underwent pars plana vitrectomy, were identified. Patients' demographic and clinical data were entered into a computerized database for review and analysis; data included age, sex, initial visual acuity, duration between onset of injury and surgery, information about the type and cause of injury, wound location and length, presence of ocular complications, and final visual acuity. RESULTS: Of the 355 open globe injuries, 14 were sustained during a traffic-related accident; the average age was 50.4 years (range: 20-85) and most (78.6%) were men. Of these 14 patients, 9 (64.3%) presented with rupture and 5 (35.7%) with laceration. Injuries were caused while driving (6 eyes; 42.9%), riding a bicycle (5 eyes; 35.7%), involved in car accident while walking (2 eyes; 14.3%), and riding a motorbike (1 eye; 7.1%). Initial visual acuity was significantly related to final visual acuity (P = 0.003, R = 0.80). The final visual acuity in patients with traffic accident-related open globe injuries was significantly better than that of the total group (P = 0.01). CONCLUSION: Traffic accident-related open globe injuries had better visual outcomes than common open globe injuries. Visual outcomes in patients with traffic accident-related open globe injuries were related to the initial visual acuity. No eyes developed endophthalmitis in patients with traffic accident-related open globe injuries.

Accuracy of ultrawide-field fundus ophthalmoscopy-assisted deep learning for detecting treatment-naïve proliferative diabetic retinopathy.

PURPOSE: We investigated using ultrawide-field fundus images with a deep convolutional neural network (DCNN), which is a machine learning technology, to detect treatment-naïve proliferative diabetic retinopathy (PDR). METHODS: We conducted training with the DCNN using 378 photographic images (132 PDR and 246 non-PDR) and constructed a deep learning model. The area under the curve (AUC), sensitivity, and specificity were examined. RESULT: The constructed deep learning model demonstrated a high sensitivity of 94.7% and a high specificity of 97.2%, with an AUC of 0.969. CONCLUSION: Our findings suggested that PDR could be diagnosed using wide-angle camera images and deep learning.

Histological investigation of the titanium fiber mesh with one side sealed with non-porous material for its application to the artificial heart system.

In this study, we investigated tissue-inducing characteristics of a titanium fiber mesh disk with one surface sealed with a non-porous material. We used sintered titanium fiber mesh (Hi-Lex Co., Zellez™, Hyogo, Japan) having a titanium fiber diameter of 50 µm and volumetric porosity of the titanium fiber mesh of 87% with an average pore size of 200 µm. The titanium fiber mesh is disk-shaped with a dimeter of 5 mm and a thickness of 1.5 mm. One side of the titanium fiber mesh disk was sealed with silicone rubber adhesive that has no venomousness and the sealed titanium fiber mesh disks were implanted in rats under the skin of the dorsal region, and they were extracted in the 4th and 12th postoperative weeks. We investigated the distribution of capillaries; also we estimated the extent of the spread of oxygen from capillaries using the diffusion equation. Microscopic observation showed that the distribution of capillaries was mainly confined to the area around the sealed titanium fiber mesh disk and that connective tissue inside the sealed titanium fiber mesh disk seemed to be in a poor condition. From estimation of the extent of the spread of oxygen from capillaries, an area in which oxygen was poorly supplied may exist in the center of the sealed titanium fiber mesh disk. In conclusion, for application of the sealed titanium fiber mesh to an artificial heart system, the thickness of the titanium fiber mesh is an important factor for keeping the inside tissue in a healthy condition.

Effect of fluid-air exchange on reducing residual silicone oil after silicone oil removal.

PURPOSE: Our purpose was to determine the effect of fluid-air exchange on the amount of silicone oil (SO) droplets remaining in the vitreous cavity after removal of the main body of the SO. METHODS: This was a retrospective comparative study of 56 eyes of 56 patients that had undergone vitrectomy with SO tamponade. Fluid-air exchange was performed during surgery in 30 eyes [Air Ex(+) group] and was not done in 26 eyes [Air Ex(-) group]. All of the eyes were examined by ultrasonography, and the images were converted to binarized image. The amount of residual SO droplets/vitreal area in the images was expressed as the, "silicone oil index (SOI)". The correlations between SOI and clinical findings were determined. RESULTS: The SOI was significantly correlated with the axial length (AL, R = 0.444, P = 0.023). The SOI in the Air Ex(+) group was significantly higher (7.4 ± 2.6%) than in the Air Ex(-) group (4.9 ± 3.4%; P = 0.004). Multiple linear regression analyses showed that the SOI was independently and significantly correlated with the AL and the Air Ex(+) group (P = 0.003, P = 0.006, respectively). CONCLUSIONS: Fluid-air exchange during vitrectomy to remove residual SO is not effective. Our findings indicate that it may increase the amount of residual SO droplets.

Measurement of hemodynamic changes with the axial flow blood pump installed in descending aorta.

We have developed various axial flow blood pumps to realize the concept of the Valvo pump, and we have studied hemodynamic changes under cardiac assistance using an axial flow blood pump in series with the natural heart. In this study, we measured hemodynamic changes of not only systemic circulation but also cerebral circulation and coronary circulation under cardiac support using our latest axial flow blood pump placed in the descending aorta in an acute animal experiment. The axial flow blood pump was installed at the thoracic descending aorta through a left thoracotomy of a goat (43.8 kg, female). When the pump was on, the aortic pressure and aortic flow downstream of the pump increased with preservation of pulsatilities. The pressure drop upstream of the pump caused reduction of afterload pressure, and it may lead to reduction of left ventricular wall stress. However, cerebral blood flow and coronary blood flow were decreased when the pump was on. The axial flow blood pump enables more effective blood perfusion into systemic circulation, but it has the potential risk of blood perfusion disturbance into cerebral circulation and coronary circulation. The results indicate that the position before the coronary ostia might be suitable for implantation of the axial flow blood pump in series with the natural heart to avoid blood perfusion disturbances.

Two-year results of metamorphopsia, visual acuity, and optical coherence tomographic parameters after epiretinal membrane surgery.

PURPOSE: To determine the 2-year results of metamorphopsia, visual acuity, and optical coherence tomographic (OCT) parameters after epiretinal membrane (ERM) removal, and to evaluate the correlations among them. METHODS: We studied 75 eyes of 75 patients with an ERM who underwent vitrectomy and membrane peeling. The best-corrected visual acuity (BCVA), metamorphopsia scores, and OCT parameters were measured at the baseline, and 1, 3, 6, 9, 12, 18, and 24 months postoperatively. M-CHARTS were used to quantify the degree of metamorphopsia. RESULTS: The mean BCVA, degree of metamorphopsia, and all of the OCT parameters except the photoreceptor outer segment (PROS) length improved significantly from that at the baseline at 24 months (P < 0.001). However, they were not significantly different from those at 12 months. The better BCVA at 24 months was correlated with the longer PROS length at the baseline (P < 0.01). The degree of metamorphopsia at 24 months was significantly correlated with that at baseline (P < 0.01). CONCLUSIONS: A postoperative follow-up period of 12 months may be sufficient to assess the improvements induced by the ERM surgery. The preoperative PROS length was the prognostic factor for the postoperative BCVA. The preoperative degree of metamorphopsia was the prognostic factor for the postoperative degree of metamorphopsia, suggesting that surgery for ERM should be performed before development of severe metamorphopsia.

Correlation between optic nerve head circulation and visual function before and after anti-VEGF therapy for central retinal vein occlusion: prospective, interventional case series.

BACKGROUND: To determine the correlation between the optic nerve head (ONH) circulation determined by laser speckle flowgraphy and the best-corrected visual acuity or retinal sensitivity before and after intravitreal bevacizumab or ranibizumab for central retinal vein occlusion. METHODS: Thirty-one eyes of 31 patients were treated with intravitreal bevacizumab or ranibizumab for macular edema due to a central retinal vein occlusion. The blood flow in the large vessels on the ONH, the best-corrected visual acuity, and retinal sensitivity were measured at the baseline, and at 1, 3, and 6 months after treatment. The arteriovenous passage time on fluorescein angiography was determined. The venous tortuosity index was calculated on color fundus photograph by dividing the length of the tortuous retinal vein by the chord length of the same segment. The blood flow was represented by the mean blur rate (MBR) determined by laser speckle flowgraphy. To exclude the influence of systemic circulation and blood flow in the ONH tissue, the corrected MBR was calculated as MBR of ONH vessel area - MBR of ONH tissue area in the affected eye divided by the vascular MBR - tissue MBR in the unaffected eye. Pearson's correlation tests were used to determine the significance of correlations between the MBR and the best-corrected visual acuity, retinal sensitivity, arteriovenous passage time, or venous tortuosity index. RESULTS: At the baseline, the corrected MBR was significantly correlated with the arteriovenous passage time and venous tortuosity index (r = -0.807, P < 0.001; r = -0.716, P < 0.001; respectively). The corrected MBR was significantly correlated with the best-corrected visual acuity and retinal sensitivity at the baseline, and at 1, 3, and 6 months (all P < 0.050). The corrected MBR at the baseline was significantly correlated with the best-corrected visual acuity at 6 months (r = -0.651, P < 0.001) and retinal sensitivity at 6 months (r = 0.485, P = 0.005). CONCLUSIONS: The pre-treatment blood flow velocity of ONH can be used as a predictive factor for the best-corrected visual acuity and retinal sensitivity after anti-VEGF therapy for central retinal vein occlusion. TRIAL REGISTRATION NUMBER: UMIN000009072. Date of registration: 10/15/2012.

Electrical characteristic of the titanium mesh electrode for transcutaneous intrabody communication to monitor implantable artificial organs.

We have developed a tissue-inducing electrode using titanium mesh to obtain mechanically and electrically stable contact with the tissue for a new transcutaneous communication system using the human body as a conductive medium. In this study, we investigated the electrical properties of the titanium mesh electrode by measuring electrode-tissue interface resistance in vivo. The titanium mesh electrode (Hi-Lex Co., Zellez, Hyogo, Japan) consisted of titanium fibers (diameter of 50 µm), and it has an average pore size of 200 µm and 87 % porosity. The titanium mesh electrode has a diameter of 5 mm and thickness of 1.5 mm. Three titanium mesh electrodes were implanted separately into the dorsal region of the rat. We measured the electrode-electrode impedance using an LCR meter for 12 weeks, and we calculated the tissue resistivity and electrode-tissue interface resistance. The electrode-tissue interface resistance of the titanium mesh electrode decreased slightly until the third POD and then continuously increased to 75 Ω. The electrode-tissue interface resistance of the titanium mesh electrode is stable and it has lower electrode-tissue interface resistance than that of a titanium disk electrode. The extracted titanium mesh electrode after 12 weeks implantation was fixed in 10 % buffered formalin solution and stained with hematoxylin-eosin. Light microscopic observation showed that the titanium mesh electrode was filled with connective tissue, inflammatory cells and fibroblasts with some capillaries in the pores of the titanium mesh. The results indicate that the titanium mesh electrode is a promising electrode for the new transcutaneous communication system.

Initial Acute Animal Experiment Using a New Miniature Axial Flow Pump in Series With the Natural Heart.

We have advocated an axial flow blood pump called "valvo pump" that is implanted at the aortic valve position, and we have developed axial flow blood pumps to realize the concept of the valvo pump. The latest model of the axial flow blood pump mainly consists of a stator, a directly driven impeller, and a hydrodynamic bearing. The axial flow blood pump has a diameter of 33 mm and length of 74 mm, and the length of anatomical occupation is 33 mm. The axial flow blood pump is anastomosed to the aorta with polytetrafluoroethylene (PTFE) cuffs worn on the inflow and outflow ports. Dp-Q curves of the axial flow blood pump are flatter than those of ordinary axial flow pumps, and pump outflow of 5 L/min was obtained against a pressure difference of 50 mm Hg at a rotational speed of 9000 rpm in vitro. The axial flow blood pump was installed in a goat by anastomosing with the thoracic descending aorta using PTFE cuffs, and it was rotated at a rotational speed of 8000 rpm. Unlike in case of the ventricular assistance in parallel with the natural heart, pulsatilities of aortic pressure and aortic flow were preserved even when the pump was on, and mean aortic flow was increased by 1.5 L/min with increase in mean aortic pressure of 30 mm Hg. In conclusion, circulatory assistance in series with the natural heart using the axial flow blood pump was able to improve hemodynamic pulsatility, and it would contribute to improvement of end-organ circulation. .

Changes of choroidal structure after treatment for primary intraocular lymphoma: retrospective, observational case series.

BACKGROUND: We report changes of choroidal structure determined by binarization of enhanced depth imaging optical coherence tomographic (EDI-OCT) images after treatment for primary intraocular lymphoma (PIOL). METHODS: Five eyes of four patients with PIOL were examined by EDI-OCT before and 6 months after intravitreal methotrexate injections. In addition, 15 eyes of 15 normal individuals controlled by age and refractive error were examined by EDI-OCT. Binarization of the EDI-OCT images was performed using publicly accessible software (ImageJ). The examined area of the subfoveal choroid was 1,500 µm wide, and the dark areas that represented the luminal areas were traced by the Niblack method. Wilcoxon signed rank test was used to determine the significance of changes in the subfoveal choroidal thickness, interstitial area, and luminal area. Mann-Whitney U test was used to compare the parameters in the eyes with pretreatment PIOL and normal control eyes. RESULTS: The subfoveal choroidal thickness was significantly decreased after treatment (P = 0.0431). In the binarized images, the interstitial area was significantly decreased after treatment (P = 0.0431), while the luminal area was not significantly changed (P = 0.8927). After delayed onset of PIOL, increased interstitial area, thickened choroid and unchanged luminal area were observed in one eye. The interstitial area and choroidal thickness were significantly increased in the eyes with pretreatment PIOL compared with the normal control eyes (P = 0.0207, P = 0.0495, respectively), while the luminal area was not significantly different (P = 0.2752). CONCLUSIONS: After treatment for PIOL, the EDI-OCT images showed a thinner choroid, and binarization of the EDI-OCT images showed significantly decreased interstitial areas compared with the luminal areas. The binarized EDI-OCT images can provide useful information on choroidal structure in eyes with PIOL, and combining these images with intraocular interleukin levels or fundus autofluorescence images should provide valuable information for determining the PIOL activity.

Binarization of enhanced depth imaging optical coherence tomographic images of an eye with Wyburn-Mason syndrome: a case report.

BACKGROUND: To report a thicker choroid and larger choroidal luminal area in an eye with Wyburn-Mason syndrome. To the best of our knowledge, this is the first report demonstrating an increase in the choroidal thickness and the luminal area in a case of Wyburn-Mason syndrome. In addition, we report the changing appearance of retinal arteriovenous malformations over a 16-year period. CASE PRESENTATION: A 27-year-old woman, who was diagnosed with Wyburn-Mason syndrome at age 11 years, visited our clinic. Her best-corrected visual acuity was 20/12.5 in the right eye and light perception in the left eye. Severely dilated, tortuous vascular loops were distributed from the optic disc over all four quadrants of the left fundus. The vascular loops in some areas were more dilated and tortuous than 16 years earlier. Optical coherence tomography (OCT) showed retinal edema with cystic changes and enlarged choroidal vessel lumens in the left eye. The subfoveal choroidal thickness was manually measured by the caliper function in the enhanced depth imaging OCT (EDI-OCT) images. Binarization of the EDI-OCT images was performed with publicly accessible ImageJ software. The examined area of the subfoveal choroid was 1,500 µm wide, and the dark areas representing the luminal areas were traced by the Niblack method. After determining the distance of each pixel, the luminal area was automatically calculated. The subfoveal choroidal thickness was 250 µm in the right eye and 462 µm in the left eye. The luminal area of the 1,500-µm-wide subfoveal choroid was computed to be 307,165.6 µm(2) in the right eye and 545,780.7 µm(2) in the left eye. CONCLUSIONS: The EDI-OCT images showed a thicker choroid, and binarization of the EDI-OCT images showed that the luminal areas were significantly larger in the affected eye, suggesting a dilatation of the choroidal vessels. The results demonstrated that conversion of EDI-OCT images to binary images was a useful method to quantify the choroidal structure.