Microvasculature of the avian eye: studies on the eye of the duckling with microcorrosion casting, scanning electron microscopy, and stereology

The microvasculature of the eye of the duckling was studied with microcorrosion casting, scanning electron microscopy, and stereology. Most blood to the eyeball first passes through the arterial ophthalmic rete mirabile, a complex of small arteries which intermixes with a similar complex of veins (venous ophthalmic rete mirabile) at the ventrotemporal angle of the eye. The present study reveals the ultrastructural anatomy and the compact, three-dimensional arrangement of vessels in this rete, which had been shown by previous investigators to function as a countercurrent heat exchanger. Vessels from this rete include the supraorbital and infraorbital arteries, which supply the eyeball anteriorly, and the ophthalmotemporal artery, which supplies the eyeball posteriorly. The internal ophthalmic and ethmoidal arteries, branches of the cerebral carotid artery, anastomose with the ophthalmotemporal artery posteriorly. Blood is distributed to the eyeball anteriorly by two ring arteries: the iridial ring artery, which circumscribes the iris and which receives blood from the long ciliary and infraorbital arteries; and the more peripheral, ciliary ring artery, which receives blood mostly from the infraorbital and ethmoidal arteries. Within the iris is a dense, freely anastomosing bed of capillaries which extends to the edge of the pupil and then loops back beneath the ciliary body. The vasculature of the ciliary body consists of radially arranged plates of anastomosing capillaries of irregular bore which mimic the contours of that organ, but permit changes in pupil diameter. The present study demonstrates the three-dimensional anatomy of the very dense capillary net of the choriocapillaris deep to the retina and the capillary mass of the pecten, and thus supports the finding of earlier investigators that nutrients diffusing from these structures nourish the avascular retina. The pecten consists of a pleated sheet of freely anastomosing capillaries which protrudes into the vitreous body from near the optic nerve. The choriocapillaris and the pecten are supplied by branches of the ophthalmotemporal artery: the former by numerous short posterior ciliary arteries, the latter by two or three arteries which further divide into one or two smaller vessels for each of its folds. Veins of the choroid layer at the periphery of the anterior surface of the eyeball, and to some extent on its lateral walls, are revealed by the corrosion-casting technique as unusual, flattened vessels of large caliber which lie in closely spaced parallel arrays. The large surface area thus created may function in heat dissipation.(ABSTRACT TRUNCATED AT 400 WORDS)     

树鼩(Tupaia belangeri chinensis)的脑底动脉环

用25只树鼩,从升主动脉灌注带色的橡胶乳液,在解剖显微镜下进行解剖观察,用目测微尺进行测量。大多数树鼩(22只)有完整的脑底动脉环。由左、右大脑前动脉向内侧各发一前交通动脉组成大脑前总动脉。前交通动脉口径为大脑前动脉的75～85％。后交通动脉口径与大脑后动脉相近,连于颈内动脉与大脑后动脉(基底动脉的分支)之间。测量了组成脑底动脉环有关动脉的口径。由于后交通动脉足够粗大,只有中断左、右颈总动脉和左、右椎动脉,才能造成全脑缺血。     

Anatomical variations of the cystic artery

Thorough knowledge about the origin of the cystic artery is surgically important, especially when intraoperative or post-operative bleeding occurs in the gallbladder fossa. The arterial supply of the gallbladder was studied in 81 livers. The gallbladder was supplied by one cystic artery in 86% and by two arteries in 14% of cases. When a single artery was present, it originated from the right hepatic artery in 53% of livers. Other origins included the anterior or the posterior sectional hepatic artery, the replacing right hepatic artery, and in 5% of cases, segmental arteries for segments 4, 5, 6 and 8. When two cystic arteries supplied the gallbladder, both most commonly originated from the right hepatic artery (7% incidence). In 1% of cases, a subsegmental branch for segment 6 and a subsegmental branch for segment 5 respectively, originated from the cystic artery.     

金丝猴(RHINOPITHECUS)的动脉

动脉在体内的分支情况与机体各部分的结构和功能及其发育情况是相适应的,随着物种的分化,动脉的分支情况也产生了差异,并在一定程度上反映出动物在进化过程中所处的地位。所以,研究动脉的分支是推导动物演化趋向的根据之一。 关于灵长类动脉的研究,已涉及绝大多数种类,但在猴科中,尚未做过金丝猴动脉的研究。本文报导了金丝猴的动脉,并与有关种类的动脉分支情况作了比较。     

Pathway of nerves with vasoactive intestinal polypeptide-like immunoreactivity to the major cerebral arteries of the rat

Summary The pathway of nerves with vasoactive intestinal polypeptide(VIP)-like immunoreactivity to the major cerebral arteries was studied in rats by means of the indirect immunofluorescent method. The fibers are densely distributed in the ethmoidal nerves and in the adventitia of both the external and internal ethmoidal arteries. Section of both ethmoidal nerves and external ethmoidal arteries before they enter the cranial cavity induced a marked reduction of VIP-like immunoreactive fibers in the walls of the vessels of the circle of Willis and its major branches. However, section of the external ethmoidal artery alone did not result in visible changes of the nerves around major cerebral arteries. The present study suggests that VIP-like immunoreactive fibers surrounding major cerebral arteries of the rat arise from fibers in the ethmoidal nerve showing immunoreactivity to VIP.     

Meningeal arteries in rhesus macaques (Macaca mulatta): implications for vascular evolution in anthropoids.

The branching patterns of meningeal arteries are reported for 200 endocast hemispheres representing rhesus monkeys (Macaca mulatta) of known cranial capacity. We detect five basic patterns for the branching of the anterior division of the middle meningeal artery and its relationship with the anterior meningeal artery. These results confirm and elaborate trends published for much smaller samples that were based on direct dissections of rhesus monkey arterial patterns. The most common pattern is that in which the anterior meningeal artery dominates the blood supply above the rostral part of the middle cranial fossa. Analysis of cranial capacities reveals that presence of this pattern on both sides of endocasts is associated with increased cranial capacity. When studied in light of published reports of anatomical dissections of cranial arteries in apes and human embryological data, the anterior meningeal artery in rhesus monkeys appears to be a possible homologue of the lacrimal meningeal artery in apes and the anterior branch of the middle meningeal artery in humans. This finding provides a step towards understanding cranial vasculature homologies that may be useful for accurately scoring the branching patterns of the meningeal arteries in monkeys, apes, and humans.     

金钱豹和猪獾冠状动脉的解剖

为了阐明金钱豹(Panthera pardus)和猪獾(Arctonyx collaris)心冠状动脉的分支分布特征及血供情况,为心脏生物学及动物学研究提供结构基础资料,利用血管铸型和组织透明方法观察研究了金钱豹与猪獾心左、右冠状动脉的分支分布.结果表明,金钱豹和猪獾的心均由左右冠状动脉营养.金钱豹左冠状动脉分为室间隔支、前降支和旋支.前降支又分出左室上支、左室中支和左室下支.右冠状动脉沿途分出右室前支、右室后下支和右室后上支.猪獾左冠状动脉分为前降支和旋支.前降支又分出室间隔支和左室前支,旋支又分出左缘支和左室后支.其右冠状动脉沿途分出右室前支、右缘支和右室后支.金钱豹和猪獾心的室间隔均由发自左冠状动脉的独立的室间隔支营养,二者左右冠状动脉在膈壁的分布属于均衡型.     

Detailed neurovascular anatomy of the serratus anterior muscle: implications for a functional muscle flap with multiple independent force vectors

A functional muscle free flap with multiple muscle segments that could be oriented independently to produce different force vectors would be beneficial in facial reanimation and upper extremity reconstruction. The serratus anterior muscle has this potential because two or more individual muscle slips can be transferred on a single vascular pedicle. Although serratus anterior muscular anatomy has been studied previously, little attention has been given to the intramuscular anatomy. Muscle slips 5 through 9 (and 10, if present) in 50 specimens from 27 cadavers were studied following intraarterial latex injection. Eight specimens were injected with a radiopaque material (latex/diatrizoate/lead mixture) for x-ray delineation of the intramuscular vascular pattern. Slips 5 through 9 are consistently supplied by a single dominant branch of the thoracodorsal artery and innervated by the long thoracic nerve. Dissection revealed that the long thoracic nerve and its branches invariably follow the artery and divide proximal to the corresponding arterial division. There is a consistent vascular pattern to each muscle slip, in which the serratus artery gives rise to common slip arteries, each of which supplies adjacent muscle slips. The mean length of a muscle slip from its origin on the rib periosteum to the division of the common slip artery is 9.6 cm. These findings imply that the slips may be separated to the level of these common slip arteries, with up to five slips transferred on a single neurovascular pedicle and each slip oriented independently to provide multiple muscle force vectors. With these possibilities, the reconstructive surgeon may be able to restore more natural facial animation and better intrinsic muscle function in the upper extremity.     

Vascularization of the corpus callosum in humans

The blood supply of the corpus callosum is studied in 20 brains by injecting the vascular system with gelatinous Indian ink. The arterial vascularization derives mainly from the anterior cerebral arteries, accessed from the median artery of the corpus callosum or from the terminal and choroidal branches of the posterior cerebral arteries. The various arteries give off perforating branches which are direct or indirect, short, of middle length or long. All these arteries concentrate on the peripheral wall of the corpus callosum. Inside of it these various arteries give off numerous terminal and collateral branches running between the nervous fibres and forming a characteristic vascular network which nourishes the capillary network. The venous vascularization of the corpus callosum is tributary to the deep venous system of the brain and concentrates on the central wall of the commissure.     

The dorsal arterial network of the wrist with reference to the blood supply of the carpal bones.

The gross examination of 50 minium injected specimens showed us the various patterns of the posterior arterial network of the wrist. This is chiefly provided by the radial artery which gives off a constant dorsal carpal branch over the posterior aspect of the trapezium. This vessel crosses the carpus transversely to the inner border of the hand and is joined in half of the cases by the interosseous artery; contribution of the posterior carpal branch of the ulnar artery was more rarely found than usually described (25%). From the arch thus formed are given off short branches which run upwards along the intercarpal joints and enter the posterior aspects of the proximal carpal bones whose lower halves seem to be the most favorably supplied. On the contrary, the distal carpal bones receive several short twigs which penetrate their posterior surfaces. Although the arrangement of the pedicles may undergo many a variation, attention must be drawn to the fact that the dorsal arteries are smaller but denser than the volar, except for the hamate. Therefore 2 different patterns of arterial supply can be described at the carpus: the blood supply of the outer and axial bones--scaphoid, trapezium, lunate, capitate--derives from the radial and the interosseous arteries and is probably shared equally by volar and dorsal branches; the inner bones--triquetrum, hamate--are primarily supplied by volar or medial branches coming almost exclusively from the ulnar artery.     

Arterial supply of the atrio-ventricular bundle and its right branch by the first diagonal artery: a dual vascularization

A case is described in which a septal artery originating from the first artery contributed to the vascular supply of the atrio-ventricular bundle, its right branch, the moderator band and the anterior papillary muscle of the right ventricle. Postmortem coronary angiograms and microdissection were use to determine the course of the arteries. The different patterns of origin of the anterior septal arteries were reviewed, and the role of these arteries as an anastomotic route in situations of proximal stenosis of the anterior interventricular artery is discussed.     

筛动脉及其分支、筛孔的显微解剖学研究

目的：从显微解剖学角度探讨筛动脉及其分支起源和走行。方法：采用固定和灌注过的成人头部标本25具50侧。显微镜下解剖筛动脉及其分支的起源和走行。观察并测量筛孔数目iDacryon点与筛前孔（DA）、筛中孔（DM）、筛后孔（DP）、视神经管眶口（DO）的距离,筛前后孔之间的距离（AP）,筛后孔与视神经管眶口之间的距离（PO）,对所得数据作统计分析。结果：筛前动脉主要起自04段,有36支（72．00％）,眶内段长（5．16±1．24）mm,管径为（0．56±0．17）mm;筛后动脉主要起自02段,有26支（56．52％）,眶内段长（9．08±2．29）mm,管径为（0．37±0．14）mm。筛孔数目以双孔最多（占54侧）,其次为三孔（占40侧）,单孔和四孔各占3侧。DA：（17．28±2．24）mm;DM：（25．46±2．74）mm;DP：（30．48±2．27）mm;DO：（36．26±2．32）mm;AP：（13．20±2．19）mm;PO：（5．78±2．17）mm。结论：获得了筛动脉及其分支起源和走行的显微解剖学数据,为影像诊断和神经外科、眼科等手术方案的制定以及介入治疗提供了解剖学依据。     

Absence of foramen spinosum and abnormal middle meningeal artery in cranial series

In comparative and evolutionary aspects in humans, the middle meningeal artery enters the cranium through the foramen spinosum, whereas in great apes the middle meningeal artery can enter the cranium through foramen spinosum, through foramen ovale or through petrosphenoid fissure. Generally, in nonhuman primates the anterior meningeal system is associated with the ophthalmic branch of the internal carotid artery. The vessels joining the two systems pass through the additional channels: the superior orbital fissure or through the cranio-orbital foramen. In anatomically modern humans, the absence of foramen spinosum involves abnormal development and course of the middle meningeal artery and it is usually accompanied with replacement of the conventional middle meningeal artery with such, arising from the ophthalmic artery system. In these cases the middle meningeal artery most often enters the middle cranial fossa through the superior orbital fissure and rarely through the meningo-orbital foramen. All skulls, investigated in the present study, belonged to adult individuals of both sexes, conditionally grouped into three cranial series--contemporary male, medieval male, and medieval female series. The absence of foramen spinosum was established only among the medieval male and female series--in 1 (0.70%) male and in 1 (0.72%) female skull on the right side and in 3 (2.13%) female skulls on the left side. In 1 (0.72%) female skull, a small atypically located foramen spinosum was established on the right side. In all of the described cases, the intracranial meningeal grooves started from the lateral edge of the superior orbital fissure and probably reflect the ophthalmic origin of the middle meningeal artery.     

Homologies of the stapedial artery in humans, with a reconstruction of the primitive stapedial artery configuration of Euprimates

Data drawn from the perspectives of paleontology, comparative anatomy, embryology, teratology, and normal adult variation were analyzed with nine homology criteria in order to determine the homologues of the stapedial artery in adult humans. It was determined that 1) the stem of the stapedial artery does not persist within the cranial cavity; 2) the stem of the ramus inferior is retained in its entirety and forms the upper portion of the stem of the middle meningeal artery; 3) the proximal part of the ramus infraorbitalis is normally absent and is replaced by a collateral shunt arising from the ramus mandibularis; 4) the ramus mandibularis is retained and forms the lower portion of the middle meningeal stem and the inferior alveolar artery; 5) the most proximal portion of the maxillary artery is formed by an anastomotic shunt connecting the external carotid artery to the ramus mandibularis; 6) the anterior division of the ramus superior is normally present and well developed; 7) the posterior division of the ramus superior is present in many individuals; and 8) the junction of the two divisions of the ramus superior with the ramus inferior usually migrates to the floor of the middle cranial fossa. The range of human arterial patterns, and those of all other euprimates, can be derived from a hypothetical primitive pattern that is very similar to that of primitive rodents. In this pattern, the stapedial artery stem enters the middle cranial fossa and trifurcates into the anterior and posterior divisions of the ramus superior and the ramus inferior. In their evolution, strepsirhines initially lose the ramus inferior and haplorhines initially reduce the stapedial artery stem.     

The Anatomy of the Circulatory System in the Arminid Nudibranch Armina maculata Rafinesque, 1814 (Gastropoda: Opisthobranchia)

In Armina maculata the heart lies anteriorly and has a large muscular ventricle and a delicate auricle running obliquely to the antero-posterior axis. The auriculoventricular valve and the aortic valve are disposed at the anterior end of the auricle and ventricle respectively. The aortic trunk is located just anterior to the ventricle and gives off several arteries, which extend through the whole body. The main arteries are: the cephalic artery (to the buccal apparatus); the posterior artery (to the notum, digestive glands, ovotestis and renal chamber); the pedal artery (to the foot); and the genital arteries (supplying the different organs of the reproductive system). These data are compared with those of other arminacean species.     

Anterior spinal arteries. Origin and distribution in man

This study was designed to extend our present knowledge of the origin and distribution of anterior spinal arteries and was carried our using 31 human cadavers with arterial injections of natural latex. The conclusions reached are that there are always one or two anterior spinal arteries (right or left), which proceed from the intracranial segment of the vertebral arteries. These arteries have a descending course, with distribution into the ventral face of the medulla oblongata and the first cervical segments of the medulla spinalis. In cases where there are two anterior spinal arteries, they anastomose with each other to form the common, unpaired and median anterior spinal artery. The different observed locations of the origins of anterior spinal arteries may be systematised into three types. Each of these types has differential characteristics: bilateral origin (type I; 77.4%), unilateral origin (type II; 9.7%) and origin in an intervertebral transversal anastomosis (type III; 12.9%). We do however subdivide the bilateral origin group, according to the calibre of the arteries, into the subtypes 'balanced' (type Ia; 22.6%), 'right dominated' (type Ib; 32.2%) and 'left dominated' (type Ic; 22.6%). The collaterals of the anterior spinal arteries which distribute into the ventral face of the medulla oblongata are described.     

Human femoral artery diameter in relation to knee extensor muscle mass, peak blood flow, and oxygen uptake

It is not known whether the diameter of peripheral conduit arteries may impose a limitation on muscle blood flow and oxygen uptake at peak effort in humans, and it is not clear whether these arteries are dimensioned in relation to the tissue volume they supply or, rather, to the type and intensity of muscular activity. In this study, eight humans, with a peak pulmonary oxygen uptake of 3.90 +/- 0.31 (range 2.29-5.03) l/min during ergometer cycle exercise, performed one-legged dynamic knee extensor exercise up to peak effort at 68 +/- 7 W (range 55-100 W). Peak values for knee extensor blood flow (thermodilution) and oxygen uptake of 6.06 +/- 0.74 (range 4.75-9.52) l/min and 874 +/- 124 (range 590-1,521) ml/min, respectively, were achieved. Pulmonary oxygen uptake reached a peak of 1.72 +/- 0.19 (range 1.54-2.33) l/min. Diameters of common and profunda femoral arteries determined by ultrasound Doppler were 10.6 +/- 0.4 (range 8.2-12.7) and 6.0 +/- 0.4 (range 4.5-8.0) mm, respectively. Thigh and quadriceps muscle volume measured by computer tomography were 10.06 +/- 0.66 (range 6.18-10.95) and 2.36 +/- 0.19 (range 1.31-3.27) liters, respectively. The common femoral artery diameter, but not that of the profunda branch, correlated with the thigh volume and quadriceps muscle mass. There were no relationships between either of the diameters and the absolute or muscle mass-related resting and peak values of blood flow and oxygen uptake, peak pulmonary oxygen uptake, or peak power output during knee extensor exercise. However, common femoral artery diameter correlated to peak pulmonary oxygen uptake during ergometer cycle exercise. In conclusion, common and profunda femoral artery diameters are sufficient to ensure delivery to the quadriceps muscle. However, the common branch may impose a limitation during ergometer cycle exercise.     

Angiology of the brain of the baboon Papio ursinus, the vervet monkey Cercopithecus pygerithrus, and the bushbaby Galago senegalensis

The investigation was undertaken to compare the blood supply and venous drainage of the brain of the baboon P. ursinus, the vervet monkey C. pygerithrus, and the bushbaby G. senegalensis with that of man, because these animals are extensively used as research models. The blood supply of the three primates was found to be similar in each case. Like man they have a complete circulus arteriosus; but they have a single anterior cerebral artery, whereas man has paired anterior cerebral arteries. The arterial supply to the cerebellum in the primates is similar to that in man, the main difference being a "common inferior cerebellar artery" which bifurcates to form the anterior inferior cerebellar and posterior inferior cerebellar arteries. In man, these arteries arise separately from the basilar artery and vertebral arteries, respectively. The dural venous drainage was also found to be similar in these primates but was far more extensive than in man. The primates have additional sinuses--the more important of these being the "basisphenoid sinus" and the petrosquamous sinus. The former drains the basilar sinus and is itself drained via the vertebral venous plexus and internal jugular vein. The latter drains via the petrosquamous foramen into the retromandibular vein. The petrosquamous sinus has a rostral extension which drains through the foramen ovale and two lateral and medial connecting sinuses which drain the cavernous and basilar sinuses, respectively. These sinuses are not found in man.     

The vascular territories of the superior epigastric and the deep inferior epigastric systems

The vascular territories of the superior and the deep inferior epigastric arteries were investigated by dye injection, dissection, and barium radiographic studies. By these means it was established that the deep inferior epigastric artery was more significant than the superior epigastric artery in supplying the skin of the anterior abdominal wall. Segmental branches of the deep epigastric system pass upward and outward into the neurovascular plane of the lateral abdominal wall, where they anastomose with the terminal branches of the lower six intercostal arteries and the ascending branch of the deep circumflex iliac artery. The anastomoses consist of multiple narrow "choke" vessels. Similar connections are seen between the superior and the deep inferior epigastric arteries within the rectus abdominis muscle well above the level of the umbilicus. Many perforating arteries emerge through the anterior rectus sheath, but the highest concentration of major perforators is in the paraumbilical area. These vessels are terminal branches of the deep inferior epigastric artery. They feed into a subcutaneous vascular network that radiates from the umbilicus like the spokes of a wheel. Once again, choke connections exist with adjacent territories: inferiorly with the superficial inferior epigastric artery, inferolaterally with the superficial circumflex iliac artery, and superiorly with the superficial superior epigastric artery. The dominant connections, however, are superolaterally with the lateral cutaneous branches of the intercostal arteries. For breast reconstruction, it would appear that prior ligation of the deep inferior epigastric artery would be of advantage when elevating the lower abdominal skin on a superiorly based rectus abdominis musculocutaneous flap. The vascularity of this flap would be further increased by positioning some part of the skin paddle over the dense pack of large paraumbilical perforators. Based on these anatomic studies, the relative merits of the superior and deep inferior epigastric arteries with respect to local and distant tissue transfer using various elements of the abdominal wall are discussed in detail.