The head structures are supplied by the common

carotid artery (A. carotis communis), one of the main

arteries of the body. In domestic mammals, except in

some species, the common carotid artery branches at

the base of the head, behind the curved ramus of the

mandible, into three terminals represented by the ex-

ternal carotid artery (A. carotis externa), internal ca-

rotid artery (A. carotis interna) and the occipital artery

(A. occipitalis) (3, 6). Of these, the most developed

branch is the external carotid artery, which distributes

through many branches to most parts of the head. The

internal carotid artery and the occipital artery supply

the brain especially and the anterior part of the spinal

cord (15, 21, 22).

The branching mode and the areas supplied by the

common carotid artery terminals show some morpho-

logical interspecific differences and also, between the

animals of the same species. The investigations of this

study had the goal to obtain comparative images of

the arterial vascularization in the head of rabbits using

complementary methods in order to describe the ana-

tomical peculiarities. To this end, the real anatomy was

analysed using dissection, we subsequently used ima-

gistic methods represented by the arterial angiogra-

phy and computerized tomography (CT) with contrast

substance. The research was carried out on 12 ani-

mals, both males and females. The main peculiarities

observed were: the variable detachment of the occi-

pital artery, being emitted by the external or internal

carotid artery, the separated detachment of the facial

and lingual artery from the external carotid artery, the

development of the superficial temporal trunk, of the

posterior auricular artery and of the transverse artery

of the face. The imagistic investigations have con-

firmed the results, latero-lateral arteriography sho-

wing in particular the branching mode of the common

carotid artery and the branches of the external carotid

artery, while, the dorso-ventral and ventro-dorsal ar-

teriography showed the distribution peculiarities of

the brain arteries. Imagistic details of the pathway of

the big arteries were obtained using CT technique.

Since the description of the vascular anatomy in small

species is more difficult using classic methods, the use

of the imagistic methods can offer additional data with

practical applicability, especially in the field of the ex-

perimental medicine.

Keywords: head arteries, rabbit, dissection,

arteriography, computerized tomography

Modul de ramificare și teritoriul deservit de termi-

nalele arterei carotide comune prezintă unele dife-

rențe morfologice inter-specii, dar și de la un individ la

altul din cadrul aceleiași specii. Investigațiile întreprin-

se în acest studiu au avut ca obiectiv obținerea unor

imagini comparative asupra vascularizației arteriale a

capului la iepure prin metode complementare de anali-

ză pentru evidențierea particularităților morfologice.

În acest scop, după descrierea morfologiei reale s-a

recurs la utilizarea tehnicilor de imagistică, respectiv

angiografie arterială și tomografie computerizată (CT)

cu substanță de contrast, cercetările efectuându-se pe

un număr de 12 animale. Principalele particularități

morfologice observate au fost desprinderea arterei

occipitale din artera carotidă externă sau internă, des-

prinderea separată a arterei linguale și faciale, dezvol-

tarea trunchiului temporal superficial, a arterei auricu-

lare posterioare și arterei transverse a feței. Investi-

gațiile imagistice au confirmat rezultatele obținute, ar-

teriografia latero-laterală evidențiind cu precădere

modul de ramificare a carotidei comune și distribuția

arterei carotide externe, in timp ce arteriografia dor-

so-ventrală și cea ventro-dorsală a permis observarea

particularităților distribuției arteriale la nivelul encefa-

lului. Detalii imagistice privind traseul marilor vase au

fost obținute prin utilizarea tehnicii CT. Întrucât la spe-

ciile de talie mică este mai dificilă descrierea morfolo-

giei vasculare prin metode clasice, utilizarea metode-

lor imagistice poate oferi date suplimentare cu aplica-

bilitate practică, în special în domeniul medicinei expe-

rimentale.

Cuvinte cheie: arterele capului, iepure, disecție,

arteriografie, computer tomograf

COMPARATIVE MORPHOLOGICAL AND IMAGISTIC ASPECTS

OF THE ARTERIAL VASCULARIZATION OF THE HEAD IN DOMESTIC RABBITS

ASPECTE COMPARATIVE DE MORFOLOGIE REALĂ ȘI IMAGISTICĂ

ALE VASCULARIZAȚIEI ARTERIALE A CAPULUI LA IEPURE

1),*) 1)C. T. COVAȘĂ , V. VULPE

Rev Rom Med Vet (2019) 29 | 4: 67-72 67

ISSN: 1220-3173; E-ISSN: 2457-7618

1) University of Agricultural Sciences and Veterinary Medicine ”Ion Ionescu de la Brad”, Faculty of Veterinary Medicine, Iasi, Romania*) Corresponding author: costica_covasa@yahoo.com

68 Rev Rom Med Vet (2019) 29 | 4

The detailed knowledge of the arterial vascula-

rization of the head is a necessity because of the im-

portance of the vascular pathology of the head and its

impact on the body health.

The rodents represent a distinct group of mam-

mals which presents various peculiarities of the ske-

leton, muscles, internal organs and also the circulato-

ry system (10, 23, 25, 26).

Although the studies on the vascular morphology

in the rabbit are relatively rare, some of them showed

many intraspecific variations regarding the origin and

the distribution area of some arteries, like the case of

the brachiocephalic trunk, subclavian artery and o-

thers (1, 2, 4, 13, 18). Similarly, other studies have

highlighted a large variability of the distribution area

of the common carotid artery and its branches at the

level of the head (5, 16, 17). Most of the studies on the

brain vascularization in rabbits were performed for ex-

perimental purposes. From this point of view, the rab-

bit represents one of the species with a high degree of

usage for experimental models in many fields (8).

Such animals are used for physiopathology studies,

hemodynamic studies, surgical and endovascular

technique. Often, these animals are used for the expe-

rimental studies of the saccular aneurysm or the

ischemic stroke. In the last period, the rabbits (Ory-

ctolagus cuniculus) have become the favourable ani-

mals for this kind of studies because their coagulation

mechanism is similar with that of the human (11, 12,

19, 20). Most of these studies are based on various

imagistic methods of investigation. In this regard, in

accordance with other studies (9, 24, 27), for impro-

ving the knowledge on the arterial morphology of the

rabbit head, we consider that, besides the dissection,

the usage of the imagistic techniques can help the des-

cription of the anatomical peculiarities and can offer

additional data on this species with practical applica-

bility.

MATERIAL AND METHODS

The research was carried out on 12 domestic rab-

bits, adults, both sexes, 8 males and 4 females, aged

1-3 years.

Anaesthesia was performed before slaughtering

the rabbits. Firstly, for the description of the real mor-

phology, a gelatine suspension colored with Chinese

India ink was injected inside the common carotid ar-

teries. After that, the dissection was performed to

high-light the branches of distribution. For pictures,

we used the Olimpus x25 Camera.

To complete the description, we used the imagis-

tic techniques, angiography and CT examination, res-

pectively. Arterial angiography of the head was carried

out on 4 animals. For this purpose, the inside of the

common carotid artery was injected with a contrasting

substance in a variable volume, 3-5 ml. The contras-TMting substance used was the Omnipaque , and after

the injection we obtained the radiographic images. For

examination, we used the latero-lateral profile, the

dorso-ventral and ventro-dorsal one. Also, unilateral

examinations were performed on the sagittal sections

of the head.

The detailed aspect of the arterial vascularization

in the head of rabbits was analysed using the CT scan-

ning technology with a contrasting substance. The ani-

mals were subjected to the scans using the Siemens

SOMATOM CT Apparatus, Emotion 16-slice configura-

tion, the sections being performed at a plan of 0.5 mm.

The obtained images were examined in a compa-

rative way to analyse as completely as possible the

morphological details. To describe these aspects, we

used the terms in accordance with the NAV, Sixth Edi-

tion, 2017 (14).

RESULTS AND DISSCUTIONS

The previous research (7), including this study,

has shown that, after the detachment of the cranial

thyroid artery (A.thyroidea cranialis), the common ca-

rotid artery (A. carotis communis) ends with the exter-

nal carotid artery and internal carotid artery, the occipi-

tal artery being a branch of one of these two. In accor-

dance with the data in the field (1, 2, 16, 17), in the ani-

mals examined displayed a variability of the detach-

ment of the occipital artery. Thus, 7 animals exhibited

the detachment of the occipital artery from the internal

carotid artery, close or very close to its origin. In 4 ani-

mals, we observed the detachment of the occipital ar-

tery from the external carotid artery, close to its origin.

In addition to the occipital artery when appropri-

ate, the main collaterals of the external carotid artery

are represented by the lingual artery (A. lingualis) and

facial artery (A.facialis), separately detached and then

ending with the maxillary artery (A.maxillaris) and the

superficial temporal trunk (A. temporalis superficialis).

The research described the possibility of common or

separate detachments of the facial artery and the su-

perficial temporal trunk (9). The superficial temporal

trunk, with a sinuous trajectory (7), emits the posterior

auricular artery (A. auricularis caudalis) and ends with

the transverse artery of the face (A. transversa faciei)

Rev Rom Med Vet (2019) 29 | 4 69

and the anterior auricular artery (A. auricularis rostra-

lis). All the terminal branches of the superficial tempo-

ral trunk are developed, distinguishing the posterior

auricular artery which ramifies at the level of the auri-

cular concha after the detachment of the deep auricular

artery (A. auricularis profunda).

The main branches of the maxillary artery are re-

presented by the alveolomandibular artery (A. alveo-

laris inferior), buccal artery (A. buccalis), middle me-

ningeal artery (A. meningea media), external ophthal-

mic artery (A. ophtalmica externa), infraorbital artery

(A. infraorbitalis) and major palatin artery (A. palatina

major) (Fig. 1.)

The latero-lateral arterial angiography (Fig. 2, Fig.

3) highlights the terminal branches of the common ca-

rotid artery (CC), together with its main branches in re-

lation to the osseous substrate. Also, one can observe

the path of the alveolomandibular (AM) artery inside of

70 Rev Rom Med Vet (2019) 29 | 4

the alveolomandibular canal, of the major palatin ar-

tery (MP), the inside of the palatin canal and palatin

groove, the infraorbital artery (IF), the inside of the

infraorbital canal, the sinuous path of the lingual artery,

the inside of the lingual body and apex, the buccal arte-

ry (B), the branches of the external ophthalmic artery

(EO) - the ethmoidal artery (E) and frontal artery (F).

Some branches of the facial artery (F) can be seen: the

sublingual artery (S) having a sinuous trajectory, and

the labiomaxillary artery (LMX). The pathway of the oc-

cipital artery (O) is highlighted towards the atlas wing

and that of the internal carotid artery (IC) towards and

inside of the cranial cavity.

By the dorso-ventral angiography (Fig. 4) and

particularly the ventro-dorsal angiography (Fig. 5, Fig.

6) we aimed to analyse especially the brain vasculari-

zation. It allows an overview of the intracranial path of

the internal carotid arteries (IC) with their cranial

(CRIC) and caudal (CDIC) branches and their contri-

bution to the formation of the Circle of Willis (WC). It is

highlighted the anastomosis of the vertebral (V) and

occipital (O) arteries and the formation of the first spi-

nal nerve arteries (FSN); from their anastomosis, ros-

trally results the basilar artery (B) and the middle spi-

nal artery, caudally. The basilar artery, placed in the

median plan, ends at the level of the Circle of Willis.

The main branches detached from the Willis Circle are

represented by the superior cerebellar arteries (SC)

and the posterior cerebral arteries (PC).

The ventro-dorsal angiography also facilitates the

observation of the pathway of these branches of the

external carotid artery: the lingual artery (L), maxilla-

ry artery (M) in the alar duct, the posterior auricular

artery (PA), the anterior auricular artery (AA), the

transverse artery of the face (TAF), the labiomaxillary

artery (LMX) and labiomandibulary artery (LMB).

The CT examination revealed the main arteries in

relation to the neighboring tissues, the most relevant

aspects being obtained in the transversal plan, espe-

cially in those sections between the middle and caudal

third of the head, corresponding to the cranial cavity,

the blood vessels being positioned symmetrically. The

arteries which can be tracked are: the lingual arteries,

Rev Rom Med Vet (2019) 29 | 4 71

the facial arteries, the maxillary arteries, the internal

carotid arteries, the middle and anterior cerebral arte-

ries, the infraorbital arteries (Fig. 7, Fig. 8).

The images in the sagittal and horizontal plan pro-

vided data especially for the pathway of the maxillary

arteries (Fig. 9, Fig. 10).

CONCLUSIONS

The vascular morphology represents a field which

requires many investigations, the small animals being

preferred due to their accessibility. In addition to the

classic methods for morphological investigations, the

72 Rev Rom Med Vet (2019) 29 | 4

modern methods, like the imagistic ones, can be suc-

cessfully used to observe the peculiarities of a struc-

ture including the variation of arterial branches, which

in the case of the rabbit revealed many differences.

The elucidations of some peculiarities of the vascu-

larization using complementary methods is morphologi-

cally important, but also clinically, the rabbit being one

of the most used species to investigate some vascular

pathogenetic mechanisms, especially for the head.

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