Optical Coherence Tomography-measured blood vessel characteristics of Port-Wine Birthmarks by depth: A cross-sectional study.

BACKGROUND: Port-Wine Birthmarks (PWB) are congenital capillary malformations requiring multiple treatments. Optical coherence tomography (OCT), a non-invasive imaging technique, characterizes vessels in cutaneous vascular lesions including PWBs. OBJECTIVE: To assess variability in blood vessel characteristics within and between individual PWBs. METHODS: OCT was used to measure blood vessel density (%) and modal vessel diameter (micrometres) at increments of 0.05 mm from skin surface to a depth of 0.50 mm at several adjacent spots of single PWBs in this cross-sectional study. Average ratios of vessel density and diameter in affected to control skin were obtained for each PWB by averaging data for all spots within a lesion. Statistical analysis was performed with linear mixed effects model using SPSS (IBM, Corp.). RESULTS: There was great variability in vessel density and diameter within and between PWBs. Depths where average ratios of vessel density were consistently greater in affected to control skin were shallow, between 0.15 - 0.2 mm deep from the skin surface. LIMITATIONS: Small sample size and device inability to measure diameters smaller than 20 micrometres. CONCLUSION: There is variability in vessel density and diameter within and between PWBs. Individualized treatment planning guided by OCT mapping should be studied further.

Artificial intelligence and hemodynamic studies in optical coherence tomography angiography for diabetic retinopathy evaluation: A review.

Diabetic retinopathy (DR) is a rapidly emerging retinal abnormality worldwide, which can cause significant vision loss by disrupting the vascular structure in the retina. Recently, optical coherence tomography angiography (OCTA) has emerged as an effective imaging tool for diagnosing and monitoring DR. OCTA produces high-quality 3-dimensional images and provides deeper visualization of retinal vessel capillaries and plexuses. The clinical relevance of OCTA in detecting, classifying, and planning therapeutic procedures for DR patients has been highlighted in various studies. Quantitative indicators obtained from OCTA, such as blood vessel segmentation of the retina, foveal avascular zone (FAZ) extraction, retinal blood vessel density, blood velocity, flow rate, capillary vessel pressure, and retinal oxygen extraction, have been identified as crucial hemodynamic features for screening DR using computer-aided systems in artificial intelligence (AI). AI has the potential to assist physicians and ophthalmologists in developing new treatment options. In this review, we explore how OCTA has impacted the future of DR screening and early diagnosis. It also focuses on how analysis methods have evolved over time in clinical trials. The future of OCTA imaging and its continued use in AI-assisted analysis is promising and will undoubtedly enhance the clinical management of DR.

Application of digital subtraction angiography in canine hindlimb arteriography.

OBJECTIVES: Research in the field of lower extremity vascular disease has increased in popularity over the years. To adequately characterize and validate the effectiveness of vascular interventions, in vivo experimentation in large animals is required. Thus, it is necessary to find a method to detect the shape and density of blood vessels in the lower extremities that can evaluate and verify the treatment measures' effectiveness and have high accuracy and repeatability. This study characterized factors that determined both the accuracy and overall value of digital subtraction angiography in lower limb arteriography using a canine animal model. METHODS: Six beagle dogs were anesthetized and immobilized on the motorized table. The femoral artery was accessed using an indwelling needle. A bolus of contrast agent was injected into the access site, and digital subtraction angiography with bolus chase technology was used to collect contrast images for analysis. At the end of the procedure, the anesthetized dogs were euthanized using an overdose of potassium chloride. After confirming the euthanasia of the dogs, the cadavers were taken to the experimental animal center of Xinjiang Medical University and processed by qualified institutional personnel. RESULTS: The final arteriographic images of the hind limbs from all six dogs were precise, and the branches of small vessels could be distinguished without any visible artifacts. CONCLUSIONS: These results suggested that arteriography using digital subtraction angiography could reveal the shape and density of blood vessels in canine animal models. This method has great potential to significantly improve research related to limb ischemia due to its simple and reproducible results.

Effects of different intensity aerobic exercises on macular retinal vascular density in patients with primary open angle glaucoma / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM: To explore the effects of different intensity aerobic exercises on macular retinal vascular density in patients with primary open angle glaucoma(POAG). <p>METHODS: Prospective case-control study, 88 eyes of 48 patients with POAG diagnosed in our hospital from January 2019 to April 2021 were included(POAG group), 43 cases(86 eyes)were included in the normal control group(control group). The fundus photographic examination without mydriasis was performed with a mydriatic fundus camera, and the operation and film reading were carried out by a special ophthalmologist. Macular vascular density was measured by macular vascular segmentation method. According to macular vascular density, 48 patients with POAG were divided into low vascular density group and high vascular density group, with 24 cases in each group. 48 patients with POAG were instructed to perform treadmill load exercise to compare the vascular density levels in macular area of patients with high intensity(76%-87% HRmax), moderate intensity(64%-75% HRmax)and low intensity(52%-63% HRmax).<p>RESULTS: The vascular density in macular area of control group was significantly higher than that of POAG group; Compared with the high vascular density group, the age and systolic blood pressure were significantly higher in the low vascular density group, and the body weight was significantly lower; In both low and high vascular density groups, the retinal vascular density of macular area under moderate intensity aerobic exercise was significantly higher than that of low intensity and high intensity aerobic exercise; Systolic blood pressure and aerobic exercise were the influencing factors of vascular density in macular area; the above results showed statistically significant differences(<i>P</i><0.05).<p>CONCLUSION: Systolic blood pressure and aerobic exercise are factors affecting macular vascular density, and moderate intensity aerobic exercise can significantly increase macular vascular density.

Relationship between blood vessel density in optic disc area and visual field index and visual field defect morphology in patients with normal tension glaucoma / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM: To study the relationship between the changes of blood vessel density in optic disc area of normal tension glaucoma(NTG)and visual field index(VFI)of glaucoma and morphological staging of visual field defect. <p>METHODS: Totally 106 patients(106 eyes)with NTG and 79 patients(79 eyes)with primary open angle glaucoma(POAG)in the hospital between December 2018 and December 2020 were selected for cross-sectional study. Among them, 1 eye of binocular disease was selected as the sample by the random number table method, and another 92 healthy subjects with physical examination in the hospital were selected as control group. All three groups completed the optic disc blood vessel density, VFI detection and visual field defect morphological staging, and the relationship between optic disc blood vessel density and VFI and visual field defect morphological staging were analyzed.<p>RESULTS: The intraocular pressure in POAG group was significantly higher than that in NTG group and control group(<i>P</i><0.05). The whole optic disc area blood vessel density, large vessel density and capillary density of NTG group and POAG group were significantly lower than those of control group(<i>P</i><0.05)while the density of avascular area was significantly higher than that of control group(<i>P</i><0.05), and there were differences in various indicators between NTG group and POAG group(<i>P</i><0.05). The VFI of NTG group and POAG group was significantly lower than that of control group(<i>P</i><0.05)while the mean visual field defect(MD)was significantly higher than that of control group(<i>P</i><0.05), and there were no statistical differences in VFI and MD between NTG group and POAG group(<i>P</i>>0.05). With the increase in visual field defect morphology staging, the whole optic disc area blood vessel density and capillary density of patients with NTG showed a significant decrease(<i>P</i><0.05). The whole optic disc area blood vessel density and capillary density of patients with NTG were positively correlated with VFI and negatively correlated with visual field defect staging, and avascular area density was negatively correlated with VFI and positively correlated with visual field defect staging(all <i>P</i><0.05). <p>CONCLUSION:Optic disc blood vessel density of patients with NTG is significantly lower than that of patients with POAG and normal people, and it is significantly correlated with VFI and visual field defect morphological staging. Among them, capillary density has the highest correlation. It can be seen that OCTA has important clinical significance for NTG diagnosis, treatment and follow-up.

Ultrastructural and histological changes in tibial remnant of ruptured anterior cruciate ligament stumps: a transmission electron microscopy and immunochemistry-based observational study.

OBJECTIVES: Anterior cruciate ligament (ACL) rupture is a common injury and has a non-union rate of 40-100%. Important cellular events, such as fibroblast proliferation, angiogenesis and change in collagen fibril thickness in the ACL remnant, as described in other dense connective tissue, might have an implication in graft recovery following ACL reconstruction. Thus we conducted a study with an aim to characterize the ultrastructural and histological features of ruptured ACL tibial stump and correlate the same with the duration of injury. MATERIALS AND METHODS: This was a prospective observational study in which 60 ruptured human ACLs were evaluated for collagen fibril thickness, blood vessel density (per mm2) and fibroblast density (per mm2) with the help of transmission electron microscopy, immunohistochemistry via CD34 antibody staining and light microscopy (H&E staining). The findings were correlated with duration of injury. RESULTS: Fifty-four male and six female patients with a mean duration of the injury of 23.01 weeks (SD = 26.09; range 2-108 weeks) were included for the study and were divided on the basis of duration of injury as follows: Group I (≤ 6 weeks; N = 16), Group II (7-12 weeks; N = 18), Group III (13-20 weeks; N = 7), Group IV (21-50 weeks; N = 12), Group V (> 50 weeks; N = 7). A significant correlation was seen with blood vessel density (r = 0.303, p = 0.01) and fibroblast density (r = - 0.503, p = 0.001). Thickness of collagen fibril did not correlate with the duration of injury (r = 0.15, p = 0.23). The thickness of the collagen reached its peak after 50 weeks following injury, whereas highest density of blood vessel and fibroblast was seen at 12-20 weeks. Matched pair analysis revealed a significant decrease in collagen fibril thickness and an increase in fibroblast density at 7-12 weeks. CONCLUSION: Following injury to ACL, the ruptured tibial stump undergoes a series of changes at the cellular level vis-à-vis changes in collagen fibril thickness, vascular density and fibroblast density that possibly suggest an intrinsic healing response. This further may have implications on the functional outcome following ACL reconstruction with remnant preservation. LEVEL OF EVIDENCE: III.

Progress in glaucoma and microcirculation changes / 国际眼科杂志(Guoji Yanke Zazhi)

@#Glaucoma is a major cause of visual dysfunction worldwide. It is a group of diseases involving the optic nerve and related structures. It is characterized by visual field defects and optic disc depression, which ultimately lead to irreversible blindness. Many years of research have found that the pathogenesis of induced glaucoma is mainly mechanical compression theory and vascular theory(microcirculation). In view of the current clinical research and further development of diagnosis and treatment, the latter has become the focus and development direction of modern research. Patients with glaucoma will have a decrease in blood vessel density in the corresponding parts such as the optic papilla and optic disc. Examination techniques such as deep convolutional neural network and OCT-A can objectively explain the changes in the corresponding parameters of their microcirculation and can monitor the progress of glaucoma. Therefore, this article discusses from the aspects of glaucoma and microcirculation, aiming to expand the clinical understanding of glaucoma microcirculation, so as to further guide the clinical.

Changes in peripapillary blood vessel density in Graves' orbitopathy after orbital decompression surgery as measured by optical coherence tomography angiography.

The purpose is to evaluate the utility of optical coherence tomography (OCT) angiography in the evaluation of Graves' orbitopathy (GO) and response to orbital decompression in patients with and without dysthyroid optic neuropathy (DON). This was a single-center, prospective case series in a cohort of 12 patients (24 orbits) with GO and ±DON, (6 orbits) who underwent bilateral orbital decompression. All patients underwent pre- and postoperative OCT angiography of the peripapillary area. Vessel density indices were calculated in a 4.5 mm × 4.5 mm ellipsoid centered on the optic disk using split-spectrum amplitude decorrelation angiography algorithm, producing the vessel density measurements. Mean change in vessel density indices was compared between pre- and postoperative sessions and between patients with and without DON. Patient 1, a 34-year-old male with GO and unilateral DON OD, showed a significant reduction in blood vessel density indices oculus dexter (OD) (DON eye) after decompression while a more modest reduction was found oculus sinister (OS) with the greatest change noted intrapapillary. Patient 2, a 50-year-old male with DON OU, showed worsening neuropathy following decompression OD that was confirmed by angiographic density indices. Patient 3, a 55-year-female with DON, showed a reduction in blood vessel density OD and increased density OS. Patients without DON showed overall less impressive changes in indices as compared to those with DON. Using OCT angiography, response to surgical treatment in GO orbits, more so in orbits with DON, can be demonstrated and quantified using vessel density indices with reproducibility.

Tumor angiogenesis as an important prognostic factor in advanced non-small cell lung cancer (Stage IIIA).

The aim of the present study was to evaluate angiogenesis by determining the micro vascular density (MVD) and the expression of vascular endothelial growth factor (VEGF-A) in advanced non-small cell lung cancer (NSCLC) tumor samples, and to analyze their associations with clinical parameters and survival. Tumor tissue specimens of fifty patients (41 males and 9 females), who underwent radical surgical treatment for NSCLC in stage IIIA (T1-3N2) were collected for immunohistochemical analysis. MVD evaluation was performed using an anti-CD31 monoclonal antibody and VEGF-A expression using a polyclonal anti-VEGF-A antibody. The results were associated with two-year survival. Statistical analysis revealed significant associations in the level of angiogenesis (high MVD) and shorter survival of patients with NSCLC (P=0.0007). VEGF-A expression showed no association with micro vascular density (P=0.51) or survival (P=0.68). There was no significant association between MVD and VEGF-A. The measurable, clinical MVD parameters could be used as a reliable prognostic factor for the survival of patients with advanced NSCLC.

Monitoring of Blood Vessel Density Using Contrast-Enhanced High Frequency Ultrasound May Facilitate Early Diagnosis of Lymph Node Metastasis.

Time-dependent alterations in the ultrasonography characteristics of lymph nodes during early-stage metastasis have not been compared with those of tumor-draining lymph nodes that do not develop tumor; this is partly due to the absence of an appropriate experimental model. In a previous study of lymph nodes with experimental early-stage metastasis, we used contrast-enhanced high-frequency ultrasound to demonstrate that an increase in lymph node blood vessel density preceded any changes in lymph node volume. In the present study, we used an experimental model of lymph node metastasis in which tumor cells metastasized from the subiliac lymph node to the proper axillary lymph node (the tumor-draining lymph node). We utilized contrast-enhanced high-frequency ultrasound to perform a longitudinal analysis of tumor-draining lymph nodes, comparing those at an early-stage of metastasis with those that did not develop detectable metastasis. We found that the normalized blood vessel density of an early-stage metastatic lymph node exhibited a progressive rise, whereas that of a tumor-draining lymph node not containing tumor began to increase later. For both types of lymph nodes, the normalized blood vessel density on the final day of experiments showed a trend towards being higher than that measured in controls. We further found that mice with an initially low value for lymph node blood vessel density subsequently showed a larger increase in the blood vessel density of the metastatic lymph node; this differed significantly from measurements in controls. The present study indicates that a longitudinal analysis of the blood vessel densities of tumor-draining lymph nodes, made using contrast-enhanced high-frequency ultrasound imaging, may be a potentially promising method for detecting early-stage lymph node metastasis in selected patients. Furthermore, our findings suggest that tumor in an upstream lymph node may induce alteration of the vascular structures in draining lymph nodes that do not contain tumor.

Lymphatic and blood vasculature in primary cutaneous melanomas of the scalp and neck.

BACKGROUND: Scalp/neck melanomas have a poor prognosis, possibly because of a rich vascular supply that prompts tumor cells' dissemination. METHODS: We compared the accuracy of immunohistochemical (IHC) staining with morphology for the identification of lymphovascular invasion in 156 scalp/neck melanomas. We then analyzed the association of vessel invasion and density with pathological features and survival. RESULTS: IHC-detected lymphatic vessel invasion (LVI) and blood vessel invasion (BVI) were identified in 34.6% and 13.5% of cases, respectively. IHC increased the LVI/BVI detection compared to morphology (40.4% vs 16.6%; p < .001). The degree of peritumoral and intratumoral blood vessel density (BVD) was greater than lymphatic vessel density (LVD). Ulceration was the only factor independently associated with intratumoral (p = .029) and peritumoral (p = .047) BVD. Tumor thickness was the only independent predictor of survival (p = .002). CONCLUSION: IHC allows accurate assessment of lymphovascular invasion in scalp/neck melanomas. In these tumors, we observed a high incidence of BVI, which deserves further investigations.

Experimental study on repairing spinal cord injury by human umbilical cord blood CD34+cell transplantation at different time points / 天津医药

Objective To investigate the effect of transplantation of human umbilical cord blood CD34+cells on spinal cord injury. Methods CD34+cells were separated from fresh human umbilical cord blood by magnetic cell sorting. Ninety-six female Wistar rats were injured at T10 by IMPACTOR MODEL-Ⅱ, and then randomly assigned to three groups:Cyclo?sporin A (CsA)+Dexamethasone (Dex) treated group (Ⅰ, n=32), local transplantation of cells+CsA+Dex treated group (Ⅱ) at the first day after operation (DAO 1, n=32), local transplantation of cells+CsA+Dex treated group (Ⅲ) at DAO 6 (n=32). BBB locomotor scoring system was used to assess the recovery of the lower limbs. The survival and neural differentiation of transplanted cells at the injury site were observed by double immunofluorescence. The tissue vitality at the injury site was ob?served by 2,3,5-triphenyl-2H-tetrazolium chloride (TTC) staining, and the blood vessel density was observed by infusing mixture of Chinese ink and glutin followed by HE staining. Results BBB score at DAO 8-56 was significantly higher inⅡgroup than that of other two groups (P<0.05). TTC staining showed that the proportion of decreased vitality area was signifi?cantly smaller inⅡgroup than that of other two groups (P<0.01). The result of gelatin ink perfusion showed that the blood vessel density at the injury site was significantly bigger inⅡgroup than that of other two groups (P<0.01). There were more survival transplanted cells inⅡgroup than those of III group (per visual field, 7.51 ± 1.00 vs 5.51 ± 0.89,t=6.051, P<0.01). All the transplanted cells didn’t differentiate into neural cells. Conclusion Human umbilical cord blood CD34+cells can promote the recovery of the lower limbs after spinal cord injury by repairing blood vessels to increase tissue vitality at the in?jury site in rats.

Contrast-enhanced high-frequency ultrasound imaging of early stage liver metastasis in a preclinical mouse model.

Monitoring angiogenesis is potentially an effective strategy for the early detection of cancer. In this study, early detection was achieved by evaluating blood vessel density in the liver using a three-dimensional contrast-enhanced high-frequency ultrasound (CE-HFUS) system and Sonazoid microbubbles. Three-dimensional CE-HFUS detected an increase in blood vessel density in the liver after intrasplenic injection of breast tumor cells into mice. The results were in agreement with immunohistochemical analysis of blood vessel density. Three-dimensional CE-HFUS using microbubbles is an attractive, novel approach for the early detection of liver metastases through quantification of new, pathological vascular growth (i.e. tumor angiogenesis).