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1.
《The ocular surface》2020,18(4):926-935
PurposeTo visualize and quantify vascular networks in individuals with ocular surface squamous neoplasia (OSSN) through optical coherence tomography angiography (OCTA).MethodCross-sectional study of OSSN patients. Vascular networks were measured by OCTA in the epithelium and sub-epithelial space in the tumors, adjacent tissue, and in the contralateral eye. Vessel area density (VAD, percent of blood vessels within 2.14 mm2), was calculated for each location. Total tumor density (TTD, percent of blood vessels within the entire tumor) was calculated. VAD was assessed separately for corneal and conjunctival locations and compared.ResultsFifteen patients with OSSN were included. The mean age was 61 ± 12 years and the majority were male (80%). The mean tumor area, volume, depth, and TTD were 28.0 ± 9.0 mm2 (range, 10.9–39.7), 9.1 ± 4.1 mm3 (range, 3.4–18.8), 334 ± 125 μm (range, 177–571), and 33.2% ± 11.0% (range, 18.7–58.8), respectively. The VAD was highest within the tumor (28.9% ± 8.7%) followed by the adjacent sub-epithelial tissue and the tissue underneath the conjunctival component of tumor. These densities were higher than the VAD in the tissues of the non-involved eye (all P < 0.05). The VAD within conjunctival component of tumor was significantly higher than those with corneal component (29.8% ± 9.5% vs. 21.1% ± 5.5%, p = 0.006). The VAD under conjunctival tumor was also significantly higher than under corneal component (24.1% ± 7.8% vs. 17.0% ± 6.1%, p = 0.024).ConclusionsOCTA imaging allowed for visualization and quantification of vessel structure and density within, under, and surrounding OSSN. 相似文献
2.
血管移植搭桥治疗巨大动脉瘤 总被引:1,自引:0,他引:1
目的探讨中、高流量血管搭桥方法对颅内巨大颅内动脉瘤的治疗。方法8例巨大和颅底复杂动脉瘤患者,主要表现头痛发病者5例,视力减退者2例,面部麻木者1例。未破裂动脉瘤6例,2例患者发生动脉瘤破裂,Hunt-Hess分级分别为Ⅰ级和Ⅱ级。血管造影证实:动脉瘤体位于颈内动脉海绵窦段(C4段)4例、床突上段(C1段)2例、大脑中动脉M2~M1段者2例动脉瘤大小为2.5~6.0cm,平均直径3.7cm。其中6例动脉瘤为梭形,2例为宽颈动脉瘤。8例患者均采用额颞开颅,骨瓣要尽可能低到颅底,以缩短搭桥移植血管在颅外走行长度。通常用7-0显微缝线吻合移植血管与颈外动脉,用8-0缝线吻合移植血管与颅内段颈内动脉和大脑中动脉。4例患者利用大隐静脉移植搭桥,4例患者利用桡动脉移植搭桥。颅内、外搭桥完毕后将动脉瘤近心端和远端的供血动脉结扎和夹闭,阻断动脉瘤的全部血供。对3例有压迫脑神经或颅内占位引起颅压高的患者,将动脉瘤切除。结果5例术后头痛消失,1例视力减退者明显改善,1例动眼神经麻痹恢复。5例术后行脑血管造影检查,3例行CT血管造影检查,7例搭桥吻合血管全部畅通,动脉瘤消失。2例术后出现暂时性一侧肢体力弱,肌力在Ⅱ~Ⅲ级之间,术后1个月完全恢复。结论中、高流量颅内外血管搭桥可作为治疗颅内巨大动脉瘤的有效方法。 相似文献
3.
急性肠系膜静脉血栓形成16例临床分析 总被引:1,自引:0,他引:1
目的 分析急性肠系膜静脉血栓形成 (ASMVT)的临床特征和诊断方法。方法 对北京友谊医院 1985年 10月至 2 0 0 2年 10月确诊的 16例ASMVT的临床资料进行分析 ,并结合文献 ,总结ASMVT的临床特征和诊断方法。结果 16例ASMVT患者 ,年龄 19~ 6 4岁 (平均 4 5 9岁 )。主要症状有腹痛 ( 16 / 16 )、腹胀 ( 16 / 16 )、呕吐 ( 10 / 16 )、发热 ( 8/ 16 ) ,主要体征有腹部膨隆 ( 16 / 16 )、腹膜刺激征( 16 / 16 )。误诊率 75 % ( 12 / 16 ) ,死亡率 4 4 % ( 7/ 16 )。结论 ASMVT的临床表现有一定的特征 ,早期彩色超声检查、诊断性腹腔穿刺、结合CT或肠系膜上动脉造影异常发现可对ASMVT做出正确的诊断 ,早期手术可以降低死亡率 相似文献
4.
Peter B. Arnold Chris A. Campbell George Rodeheaver Wyndell Merritt Raymond F. Morgan David B. Drake 《Hand (New York, N.Y.)》2009,4(3):302-307
The purpose of this study was to demonstrate that perivascularly applied botulinum toxin-A (BTX) increases the diameter of
treated blood vessels in a rat femoral vessel exposure model. Six adult Sprague–Dawley rats were used and bilateral femoral
artery and vein exposures were performed. Five units of BTX were applied to the experimental side and an equal volume of sterile
saline was applied to the control side. Digital images of the vessels were obtained at the following time points: pretreatment,
immediately posttreatment, and postoperative days (POD) 1, 14, and 28. Vessel diameters were equivalent at baseline and immediately
following application of BTX and saline. The BTX artery was significantly larger than the control artery on POD 1 and 14.
The BTX treated artery was significantly larger than all other vessels on POD 14 (p < 0.05) as well as all prior time points (p < 0.01). Direct perivascular application of BTX increases the diameter of rat femoral vessels as early as POD 1. The affect
is most robust on POD 14 where the artery was significantly larger than all other vessels at all time points. It is likely
that the increased diameter of blood vessels results in an increased blood flow across the area of dilation. Such an increase
in flow may serve to improve end-organ perfusion in microvascular procedures. 相似文献
5.
F. D. Knollmann J. C. Bck S. Teltenktter W. Wlodarczyk A. Mühler Th. J. Vogl R. Felix 《Journal of magnetic resonance imaging : JMRI》1997,7(1):191-196
The purpose of our research was to determine the effects of superparamagnetic iron oxide on MR imaging of the portal venous system. Eight piglets were examined in deep anaesthesia and respiratory arrest using a time-of-flight magnetic resonance fast low angle shot, two-dimensional angiography sequence at 1.5T. MR angiograms were acquired precontrast and after intravenous administration of a cumulative dose of 10, 20 and 40 μmol/kg SHU 555A, a superparamagnetic iron oxide contrast agent for MR imaging with a particle size of 60 nm. For each dose, two subsequent sets of scans were obtained and reconstructed by a maximum-intensity-projection algorithm. Hepatic parenchymal and portal venous signal intensities were measured, and portal vein contrast calculated for each set of scans. All examinations were visually rated as to portal vein contrast and homogeneity by two blinded observers. Receiver operating characteristics of both observers were analyzed. The contrast agent reduced hepatic parenchymal signal in a dose-dependent way. After a cumulative dose of 10 μmol iron oxide, hepatic parenchymal signal intensity decreased to 63 ± 6% (average of measurements at 4 and 14 minutes, mean ± standard error of the mean), after 20 μmol to 24 ± 3%, and after 40 μmol to 12 ± 1% of control. Intra-vascular signal in the left main portal vein branch increased to 117 ± 6%, 127 ± 10%, and 133 ± 9% of control, respectively. The contrast-to-noise ratio of the portal vein improved (521 ± 90%, 891 ± 178%, and 995 ± 201% of control in the left portal vein main branch). Intravascular signal intensities increased slightly. The combined effect improved contrast of the portal vein stem and its branches. Receiver operating characteristics analysis documented dose-dependency of contrast medium effects on portal venous contrast and intravascular homogeneity. Visual rating also indicated a positive effect on portal venous contrast. The superparamagnetic iron oxide agent improved portal venous contrast with surrounding hepatic parenchyma in this normal animal model, and could potentially result in more accurate diagnosis of portal venous pathology. 相似文献
6.
7.
以猪作为动物模型,通过分层抽样,制作各向同性切片,在图像分析仪下对超薄皮瓣的血管密度进行了观察。结果表明:超薄皮瓣血管密度于术后第5天开始出现显著性变化。这种变化首先出现在超薄皮瓣存活部分的远端,之后渐至近端。这种变化在超薄皮瓣血运重建过程中起主要作用。 相似文献
8.
W. D. Boeckx V. V. Vijay Haribhakti L. Bosmans J. A. Gruwez 《European journal of plastic surgery》1992,15(3):127-132
Summary In 50 rats, different types of end-to-side carotid artery anastomoses were compared. In one technique, a longitudinal split in the long axis of the vessel was performed to enhance the diameter of the anastomosis. This theoretical advantage was not confirmed in this series. The clamping time, anastomoses time, and tamponade time were increased significantly when compared with a simple, slightly oblique end-to-side anastomosis. This study highlighted that the most simple type of end-to-side anastomosis gave less bleeding, achieved a quicker water-tight anastomosis and decreased the risk of late problems. 相似文献
9.
Although tumour vasculature constitutes a biological factor playing a crucial role in the radiation response of tumours, the current procedures of assessment are semiquantitative, typically employing visual examination of stained histological material. Such techniques are also time consuming, and inefficient of extracting essential information on the vascular network. Image analysis has yet to contribute significantly in this direction, and most studies to date focus on blood vessel segmentation through empirical, user-selected thresholds. The present paper proposes an alternative segmentation approach, based on a probabilistic relaxation algorithm, applied in microscopic images of stained tissues. After image partitioning various information is obtained, such as vascular domains and geometrical characteristics of vessels. 相似文献
10.
Significant association of strictures and internal fistula formation in Crohn’s disease 总被引:1,自引:0,他引:1
Oberhuber G Stangl PC Vogelsang H Schober E Herbst F Gasche C 《Virchows Archiv : an international journal of pathology》2000,437(3):293-297
Intestinal inflammation in Crohn’s disease (CD) may be complicated by the occurrence of strictures and fistulae. The pathogenesis
of fistula formation is unknown. We therefore wanted to determine whether mechanical factors might contribute to the development
of fistulae. Furthermore, we tried to define the path of internal fistulae through the muscular layer. For this purpose, surgical
resection specimens from 42 consecutive patients with CD were prospectively studied. In gross examination the whole bowel
was cut into circumferential cross sections 0.3 cm thick. Abnormal areas were histologically examined. Strictures were found
in 38 patients (90.5%), and fistulae were observed in 27 (64.3%) patients. In 11 (40.7%) specimens fistulae were found within
a stricture, in 15 (55.6%) at the proximal end, and in 1 (3.7%) no stricture was found. In 7 (25.9%) cases with fistulae,
herniated mucosa was found within the muscularis propria or the subserosa. In 7 (25.9%) cases a blood vessel was identified
near a fistula traversing the muscularis propria. From these findings we conclude that that mechanical factors may contribute
to fistula formation. This is further supported by the fact that fistulae appear to traverse the muscular layer along piercing
vessels.
Received: 21 January 2000 / Accepted: 7 March 2000 相似文献