Three-dimensional morphometrical analysis of the M1 segment of the middle cerebral artery: potential clinical and neurosurgical implications

With an increase in the understanding of the formation and treatment of cerebral aneurysms and an improvement in imaging technology, actual standardized measurement values for the cerebral arteries are necessary. Therefore, the aim of this study was to provide a detailed assessment of the three-dimension (3D) morphology (vessel's curvature and trajectory) and 3D-morphometry of the M1 segment of the middle cerebral artery using computer tomography angiography (CTA) images. The DICOM files from CTA of 40 male and 75 female individuals with a mean age of 50.1 years were analyzed using an interactive postprocessing 3D volume-rendering algorithm. Specifically, the M1 segment was evaluated. Calculations included the length, internal diameter, volume, deviation (DI) and tortuosity indices (TI). The M1 segment had a mean internal diameter of 2.23 mm and was greater in men. M1 asymmetry was identified in 23.4% of the individuals and was more common in women. The mean length was 15.62 mm and the left M1 segments were a little longer. The mean volume of the M1 segments was 63.92 mm(3) , and this was typically greater in men and on the left sides. The mean TI and DI for the M1 segment were 0.91 and 2.17 mm, respectively. Therefore, the M1 segments are only slightly curved or straight in their course. In addition, the longest vascular M1 segments are more deviated (curved) and more tortuous. Such standardized data as presented herein may be useful in the preprocedural evaluation of patients with intracranial vascular pathology of the M1 segment.     

Relationship between the morphology of A-1 segment of anterior cerebral artery and anterior communicating artery aneurysms

Background

The anterior communicating artery (ACoA) is one of the most frequent sites for cerebral aneurysm. The peculiar directions of projection of aneurysms offer great challenges to clinical treatment.

Objetives

To establish the relationship between morphology of A-1 segment of anterior cerebral artery (ACA) and aneurismal projection.

Methods

Randomly selected digital subtraction angiography data of 264 anterior communicating artery aneurysms (ACoAA) cases and 296 cases of other cerebral vascular diseases in the same period were retrospectively analyzed.

Results

Among 264 ACoAA patients, the morphology of A-1 segment showed type 1a in 158 sides, type 1b in 11, type 2a in 35, type 1 2b in 87, type 3 in 171 and absence in 66. The morphology of A-1 segment in 296 patients with other cerebral vascular diseases displayed type 1a in 195 sides, type 1b in 20, type 2a in 47, type 2b in 74, type 3 in 217 and absence in 39. The non-visualization of A-1 segment in the group of ACoAA occurred more than in the control group (χ²=11.482, p=0.001). The classifications of ACoAAs in 264 patients were confirmed as anterior-superior type in 121 cases, anterior-inferior type in 105, complicated type in 16, posterior-inferior type in 12 and posterior-superior type in 10. The correlation between morphology of A-1 segment of ACA and classifications of ACoAA was significant (p=0.000; C=0.619, p=0.000). The direction of ACoAA was downward when the A-1 segment of ACA was Type 1a or Type 2a, and was upward when it was Type 1a or Type 2a and was upward or downward or complicated when it was Type 3.

Conclusion

The relationship between morphology of A-1 segment of ACA and classification of ACoAA is clarified in the present study, which is helpful to surgical treatment.     

Three‐dimensional visualization of the cutaneous angiosome using angiography

The purpose of this study was to establish the three‐dimensional (3D) architecture of the cutaneous angiosome for assessment and design of the perforator flaps. Two fresh cadavers were injected with carboxymethyl cellulose (CMC)/lead oxide and computed tomography (CT) scanned before and after the injection. The various parts of the cutaneous and subcutaneous tissue derived from one of the injected cadavers were also CT scanned. Three‐dimensional reconstruction of the cutaneous angiosome and the two flap designs were performed using Materialise's Interactive Medical Image Control System (MIMICS). Both the reconstructed cutaneous angiosomes and the digital flaps can be displayed independently or in conjunction with bones, source arteries, and skin. The 3D architecture of the cutaneous angiosome ensures clear display of the spatial location, distribution range, and anastomoses relationship of the cutaneous perforators. In addition, the caliber, length, and position of a particular source artery are illustrated in the exact spatial location. As a result, the technique provides visualization of the general area and the expandable direction of a respective flap. This technique has the potential to play an important role in assessing perforator blood supply territory and in the design of new flaps.Clin. Anat. 2013. © 2012 Wiley Periodicals, Inc.     

应用MRA研究大脑前动脉A1段发育与交通动脉开放之间的关系

目的　探讨大脑前动脉A1段发育与前后交通动脉开放情况之间的关系。方法 回顾性分析了107例3.0T磁共振血管成像（MRA）无脑血管病的检查者和体检者。观察双侧大脑前动脉A1段发育、前交通动脉和双侧后交通动脉开放情况,测量双侧大脑前动脉A1段、前交通动脉及后交通动脉的管径,分析二者的相关性。  结果　①右侧大脑前动脉A1段发育不良占22.43%（24/107）,缺如占0.93%（1/107）,左侧大脑前动脉A1段发育不良占16.82%（18/107）,缺如占1.87%（2/107）。②前交通动脉开放占47.66%（51/107）。③单侧或双侧后交通动脉开放共有39例,其中双侧同时开放占21例,仅左侧开放占7例,仅右侧开放占11例。④大脑前动脉A1段发育不良与交通动脉开放相关（r=0.654,P＜0.01）。  结论 大脑前动脉A1段发育不良可引起交通动脉代偿性开放。     

320排螺旋CT三维重建大脑前动脉的临床影像解剖学研究

目的　观测大脑前动脉的起源、走行及分支分布规律,期为脑血管疾病的诊疗提供影像学依据。 方法　随机收集100例无血管疾病的脑部多层螺旋CTA影像资料,利用其自带工作站进行图像后处理,观察大脑前动脉的影像解剖学结构。 结果　（1）测得大脑前动脉各段的数值,大脑前动脉A1段长度、内径及A1-A2夹角左右侧有统计学差异;（2）大脑前动脉走形变异率20%（20/100）,其中左侧A1段优势征9%,右侧A1段优势征5%,左侧A1段缺如1%,双侧大脑前动脉发育不良1%,左侧A4、A5段代偿供血1%,右侧A1段优势征合并同侧A2~A5段狭窄（由左侧A2~A5段代偿供血）1%,A4、A5共干1%,双侧A1段畸形1%;（3）大脑前动脉单干型71%,双干型29%。 结论　多层螺旋CTA能清晰立体地显示大脑前动脉的全长和主要分支及其解剖变异;大脑前动脉的变异复杂,左右差异显著,可为临床病变的早期诊断和治疗提供可靠依据。     

纵裂入路处理大脑前动脉远段动脉瘤的外科策略-解剖研究

目的：通过对大脑前动脉远段的显微解剖,尤其是A3段下半胼周与胼缘动脉间关系,旨在提出处理大脑前动脉远段动脉瘤的外科策略。方法：在10具血管经彩色乳胶灌注的尸头上检查大脑前动脉远段区域的显微解剖,了解胼周动脉胼下段与胼缘动脉及胼周动脉A2段与额极动脉的关系,同时测量鼻根部与胼缘动脉起点处近端胼周动脉长轴延长线与额部交点（PC点）间的距离,并模拟外科入路至大脑前动脉远段动脉瘤。结果：胼周胼缘动脉结合部位于A3段的胼上段和胼下段分别占55％和45％,对于胼下型者,获得载瘤动脉的近端控制较为困难。在尸头标本和T2RMRI正中矢状位上,从鼻根部到PC点的平均距离分别是31.52 mm和34.64 mm。通过前纵裂入路接近PC点下方大脑前动脉远段的胼下动脉瘤并建立有效的控制仅有一有限的操作空间。结论：当在PC点上方入路时,在解剖和夹闭动脉瘤前要想建立有效的近端控制,切开胼胝体前端是必要的。PC点是计划胼下型大脑前动脉远段动脉瘤外科策略的重要外科标志。     

经额底纵裂入路前交通动脉复合体的显微解剖研究

目的探讨显微解剖下经额底纵裂入路及相应的前交通动脉复合体相关指标,分析前交通动脉复合体结构分布情况。方法选择完整浸泡于10%福尔马林的成人尸头标本15具(30侧),在显微镜下经额底纵裂入路进行解剖,检测和分析大脑前动脉远侧部位和前交通动脉复合体的显微解剖相关指标,观察重要动脉血管分布情况。结果大脑前动脉A1段的左侧管径(2.67±0.29)mm,长度(133.68±1.63)mm;右侧管径(2.24±0.35)mm,长度(13.21±1.31)mm;出现变异的标本有2例(13.3%)。A2段的左侧管径(2.48±0.43)mm,长度(19.24±3.27)mm;右侧管径(2.51±0.52)mm,长度(20.15±3.54)mm;均未见变异和不对称情况。前交通动脉的长度为0~8.9 mm,平均(3.51±0.88)mm;直径为0~4.0 mm,平均(1.24±0.61)mm。前交通动脉的穿通支有1~5支,平均(2.3±1.01)支。Heubner回返动脉未见发育异常,其长度为21.14~37.52 mm,平均(27.11±3.15)mm。结论经额底纵裂入路对人体头颅进行解剖,分析前交通动脉复合体相关指标,明确了该部位的解剖结构及分布情况,有助于指导该部位前交通动脉复合体的结构分析、病变探索和临床手术。     

Three‐dimensional computer graphics‐based ankle morphometry with computerized tomography for total ankle replacement design and positioning

Morphometry of the bones of the ankle joint is important for the design of joint replacements and their surgical implantations. However, very little three‐dimensional (3D) data are available and not a single study has addressed the Chinese population. Fifty‐eight fresh frozen Chinese cadaveric ankle specimens, 26 females, and 32 males, were CT‐scanned in the neutral position and their 3D computer graphics‐based models were reconstructed. The 3D morphology of the distal tibia/fibula segment and the full talus was analyzed by measuring 31 parameters, defining the relevant dimensions, areas, and volumes from the models. The measurements were compared statistically between sexes and with previously reported data from Caucasian subjects. The results showed that, within a general similarity of ankle morphology between the current Chinese and previous Caucasian subjects groups, there were significant differences in 9 out of the 31 parameters analyzed. From a quantitative comparison with available prostheses designed for the Caucasian population, few of these designs have both tibial and talar components suitable in dimension for the Chinese population. The current data will be helpful for the sizing, design, and surgical positioning of ankle replacements and for surgical instruments, especially for the Chinese population. Clin. Anat. 659–668, 2014. © 2013 Wiley Periodicals, Inc.     

Anatomic basis for surgical approach to the distal segment of the posterior cerebral artery

Summary The distal segment of the posterior cerebral artery (PCA), which extends from the junction with the posterior communicating artery to its terminal division into the parieto-occipital and calcarine arteries, was examined in 37 brains. Three types of distal segment were distinguished. In the first type (42.9 %), the terminal division was located either in the calcarine sulcus or in the quadrigeminal cistern. In the second type (41.4 %), the terminal division had the same position, but the distal segment, in addition to its terminal stems, also gave off the common temporal artery. In the third type (15.7 %), the terminal division was seen in the ambient cistern. The distal segment of the PCA gave rise to several collateral branches: the collicular artery (2.8 %), the anterior (28.6 %), middle (30.0 %), and posterior (28.6 %) hippocampal arteries, the proximal (82.9 %) and distal (20.0 %) lateral posterior choroidal arteries, the proximal (40.0 %) and distal (41.4 %) medial posterior choroidal arteries, the peduncular, thalamogeniculate and splenial branches, the lingual gyri artery and the temporal arteries. Several anatomic variants of the distal segment were observed in this study: fenestration of the distal segment (1.4 %), location of the distal segment dorsal to the uncus (2.8 %), origin of the collicular (2.8 %) and anterior choroidal arteries (1.4 %) from the distal segment, and protrusion of the parieto-occipital arterial loop into the lateral ventricle (2.8 %). The authors discuss the clinical significance of these anatomic data.

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Bases anatomiques de l'abord chirurgical du segment distal de l'a. cérébrale postérieure

Résumé Le segment distal de l'a. cérébrale postérieure (ACP) s'étend de la jonction avec l'a. communicante postérieure à sa division terminale en a. pariétooccipitale et a. calcarine. Trente-sept cerveaux ont été disséqués dans cette région. Trois types de segment distal ont été distingués. Dans le premier type (42,9 %), la division terminale était localisée dans la fissure calcarine ou dans la citerne quadrigéminale. Dans le 2e type (41,4 %), la division était localisée dans la même région mais, indépendamment des deux systèmes terminaux, il existait un tronc commun temporal. Dans le troisième type (15,7 %), la division terminale de l'a. vertébrale postérieure était localisée dans la citerne ambiante. La portion distale de l'a. cérébrale postérieure donne naissance à plusieurs collatérales: l'a. quadrigéminale (2,8 %), les a. hippocampiques antérieure (28,6 %), moyenne (30 %) et postérieure (28,6 %), les a. choroïdiennes postéro-latérale proximale (82,9 %) et distale (20 %), les a. choroïdiennes postéro-médiale proximales (40 %) et distale (41 %), les a. pédonculaire, thalamogéniculée et spléniale, et enfin l'a. du gyrus lingual et les artères temporales. Plusieurs variétés anatomiques du segment distal de l'ACP ont été observées au cours de cette étude: fénestration (1,4 %), segment distal dorsal par rapport à l'uncus (2,8 %), origine distale de l'a. colliculaire (2,8 %), origine cérébrale postérieure et de l'a. choroïdienne antérieure (1,4 %), protrusion intraventriculaire de l'artère pariétooccipitale (2,8 %). Les auteurs discutent les conséquences cliniques de cette étude anatomique.

     

大脑前动脉A1段的显微解剖与数字减影血管造影对照观测及临床意义

目的 为临床选择颅内血管支架的类型和放置部位提供解剖学基础。方法 选取尸头标本20具,经双侧翼点入路显微解剖观测大脑前动脉A1段及其穿支血管。选取无病变的全脑DSA 100例,观测大脑前动脉A1段的走行及其穿支的开口部位。结果 显微解剖大脑前动脉A1段的长度和直径分别为（13.55±1.43） mm、（2.43±0.37） mm,DSA血管造影的长度和直径分别为（13.42±1.57） mm、（2.28±0.40） mm,显微解剖与DSA血管造影直径的差异有统计学意义（P〈0.05）。大脑前动脉A1段的穿支发自其后上壁,近侧段穿支数目（2.55±0.39）支,中间段（0.52±0.46）支,远侧段（1.12±0.11）支,近侧、中间、远侧段的穿支数目的差异均有统计学意义（P值均〈0.05）。男性较女性的大脑前动脉A1段长、直径粗,两者差异均有统计学意义（P值均〈0.05）。结论 大脑前动脉A1段的显微解剖与数字减影血管造影对照观测对临床选择颅内血管支架的类型和放置部位,避免血管支架阻塞穿支开口处,防止术后穿支供应区域缺血等具有重要的临床意义。     

以胫前返血管为蒂腓骨上段移植的应用解剖

目的:为胫前返血管蒂腓骨瓣的设计提供解剖学基础。方法:30侧经动脉红色乳胶灌注的成人下肢标本,解剖观测胫前返动脉的起始、走行、分支及分布。结果:胫前返动脉始于胫前动脉,起始点距腓骨头尖下(4.5±0.7)cm(3.0～6.0cm),动脉主干长(0.5±0.2)cm(0.2～1.2cm),外径(2.0±0.4)mm(1.3～3.0mm),伴行静脉2条,外径为(2.1±0.5)mm(1.5～3.0mm)和(2.6±0.4)mm(1.7～3.2mm)。胫前返动脉腓骨头支1～2支,外径(1.7±1.3)mm(0.6～2.1mm),分布于腓骨头的前内侧面骨膜,并与其它来源的腓骨上段骨膜支构成动脉网。腓骨头支起始点至胫前返动脉起始点长度为(1.0±0.4)cm(0.3～1.8cm),其中长度≥1.0cm者占46.7%。腓骨头支起始点以远1.5cm处的胫前返动脉外径为(1.4±0.5)mm(0.8～2.1mm)。结论:胫前返血管蒂腓骨瓣的的设计具有可行性,为临床带血管腓骨上段移植提供一种新的可供选择的血管蒂。     

大脑前动脉的A1优势征及在前交通动脉瘤脑血管造影诊断中的意义

目的：探讨A1优势征的影像学表现及其出现率与大脑前交通动脉瘤的关系.方法：回顾性分析128例脑动脉瘤数字减影脑血管造影的影像学资料.以大脑前交通动脉瘤作为试验组,其他部位的动脉瘤作为对照组.结果：128例病人中,共139个动脉瘤.前交通动脉瘤49个,后交通动脉瘤41个,基底动脉瘤29个,大脑中动脉瘤14个,颈内动脉瘤6个.A1优势征58例,A1对称75例.结论：前交通动脉瘤Al优势征多见,其出现率与其他部位脑动脉瘤之间存在显著差异（P＜0.05）.     

大脑前动脉和中动脉水平段的立体定位及其临床意义

在100套正常成人脑血管造影正、侧位 X 线片上,测量了颈内动脉分杈点和大脑前、中动脉由水平位转向上的转角点在立体坐标中的位置。该坐标的原点位于外耳门前上缘,向前至眶下缘最低点的连线为 x 轴;向上的垂线为 y 轴:伸向内侧垂线为 z 轴。在 xoy 平面上可确定大脑前、中动脉在颅侧面投影位置,在 z 轴上的数值可确定它们在颅侧面的深度。     

The supreme intercostal artery includes the last cervical intersegmental artery (C7) ‐ angiographic validation of the intersegmental nomenclature proposed by Dorcas Padget in 1954

In 1954, Dorcas Padget wrote a note that settled the debate over the labeling of the intersegmental arteries (ISAs) and the level of origin of the subclavian artery (SubA), in agreement with earlier observations made by Hochstetter in the rabbit (1890) and Schmeidel in man (1932). In her proposed nomenclature, Padget introduced the name of proatlantal artery and confirmed that the SubA was associated with the sixth ISA rather than the seventh. However, a generally unnoticed consequence of this now widely accepted terminology lays in its incompatibility with the traditional view of the costocervical trunk (CT), regarding in particular the anatomy of the supreme intercostal artery (SIA). If the SubA derives from the sixth cervical ISA (ISA 6), and the CT provides the first and second posterior IAs (ISA 8 and 9), the seventh cervical ISA (ISA 7) then remains unaccounted for. The purpose of this study was to examine Padget's nomenclature in the light of modern angiographic material to identify the missing seventh ISA. Our findings validate the terminology used by Padget, including the addition of a pro‐atlantal artery and the identification of the ISA most commonly associated with the SubA as the sixth ISA, but they also emphasize the need to redefine the anatomy of the SIA to incorporate the seventh cervical ISA. Anat Rec, 297:810–818, 2014. © 2014 Wiley Periodicals, Inc.     

Three‐dimensional orientation of the acetabulum

This study was designed specifically to determine the normal acetabular orientation and femoral head covering, and whether these are affected by age or sex. Computed tomographic images of normal Japanese hip joints were used (males 60, females 60; mean age 48.3 years, range 15–79 years). Male and female age profiles were matched. The reconstructed 3‐D pelvic images were aligned in the anatomical pelvic coordinate system. The acetabular orientation angles and femoral covering angles were measured in the sagittal, coronal, and horizontal planes. In the sagittal plane, the acetabular orientation angle was operative anteversion (O‐av), and the femoral covering angles were the anterior and posterior center‐edge angles (ACE and PCE). In the coronal plane, they were the Sharp angle (SA) and the lateral center‐edge angle (LCE). In the horizontal plane, they were anatomical anteversion (A‐av) and the anterior and posterior sector angles (ASA and PSA). The O‐av, SA, and A‐av were smaller in the male than the female acetabulum (P < 0.01). SA in both males and females was inversely correlated with age (P < 0.01). Both male PCE and PSA were significantly smaller than those of females, while male ASA was larger than female ASA (P < 0.05). The male acetabulum is directed further outward and downward than the female one. However, this does not indicate that the male acetabulum covers the femoral head more, because there is no significant sex difference in the LCE. Femoral coverage is more posteriorly biased in females than in males owing to pelvic inclination. Clin. Anat. 30:753–760, 2017. © 2017Wiley Periodicals, Inc.     

胫前动脉踝上皮支皮瓣的显微外科解剖

目的 :报道胫前动脉踝上皮支皮瓣的显微外科解剖学基础。方法 :在 14侧经动脉灌注红色乳胶成人下肢标本 ,解剖观测胫前动脉踝上皮支的起始、走行、外径、长度及分支等 ,2侧成人下肢标本灌注墨汁观察该皮支的墨染范围。结果 :胫前动脉踝上皮支于踝间连线上方 ( 3 .5± 0 .6)cm自胫前动脉发出 ,然后向小腿内侧方向绕过胫骨前缘分出升支和降支 ,升支紧贴胫骨前内侧骨面 ,向内上方向行至一段距离后穿深筋膜入皮。踝上皮支长 ( 2 .1± 0 .6)cm ,起点外径 ( 1.1± 0 .2 )mm ,伴行静脉 2条。升支入筋膜前外径 ( 0 .4± 0 .1)mm。降支向内下方向走行 ,并与踝前血管网吻合。结论 :胫前动脉踝上皮支是胫前动脉在小腿踝上部的主要皮血管 ,分支营养骨膜 ,可在小腿中下段设计以此血管为蒂的皮瓣、骨膜瓣、骨膜皮瓣或骨皮瓣。