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1.
The development of the venous drainage from the equine hypophysis cerebri was investigated in embryos and fetuses ca. 22nd to 270th day of gestation. The early venous drainage was represented by the right and left retrohypophysial veins which were tributaries of the primary head veins. In later development an anastomosis was formed between the contralateral retrohypophysial veins. This anastomosis was named the retrohypophysial sinus which was identical with the caudal intercavernous sinus of the postnatal animals. The development of the rostral intercavernous sinus was not observed. The right and left cavernous sinuses developed secondarily from the retrohypophysial sinus. The venous drainage was directed rostrolaterad into the ophthalmic veins. In addition to the rostrolateral route, a caudoventral route, represented by the right and left ventral petrosal sinuses, developed from the retrohypophysial sinus relatively late in the fetal period. Both the rostrolateral and caudoventral routes joined eventually the external jugular system basically resembling postnatal conditions.  相似文献   

2.
Dural sinuses in the pig and their extracranial venous connections   总被引:1,自引:0,他引:1  
The dural sinuses of the pig and their connections with veins of the head and neck have been described. The rostral epidural rete mirabile and the cavernous venous sinus complex have been described in detail, and speculation about their possible role in brain temperature regulation was made.  相似文献   

3.
Variations in intracranial dural venous sinus anatomy have been widely reported in humans, but there have been no studies reporting this in dogs. The purpose of this retrospective study was to describe variations in magnetic resonance (MR) venographic anatomy of the dorsal dural venous sinus system in a sample population of dogs with structurally normal brains. Medical records were searched for dogs with complete phase contrast, intracranial MR venograms and a diagnosis of idiopathic epilepsy. Magnetic resonance venograms were retrieved for each dog and characteristics of the dorsal dural sinuses, symmetry of the transverse sinuses and other anatomic variations were recorded. A total of 51 dogs were included. Transverse sinus asymmetry was present in 58.8% of the dogs, with transverse sinus hypoplasia seen in 39.2%, and aplasia in 23.5% of dogs. For 70.6% of dogs, at least one anatomic variation in the dorsal sagittal sinus was observed, including deviation from the midline (33.3%) and collateral branches from either the dorsal sagittal sinus or dorsal cerebral veins (54.9%). In 5 dogs (9.8%) a vessel was also identified running from the proximal transverse sinus to the distal sigmoid sinus, in a similar location to the occipital sinus previously reported in children. Findings from this study indicated that, as in humans, anatomic variations are common in the intracranial dural venous sinus system of dogs. These anatomic variations should be taken into consideration for surgical planning or diagnosis of cerebrovascular disease.  相似文献   

4.
5.
The dural sinuses of one-humped camel (Camelus dromedarius) and their connections with veins of the head and neck were described and, whenever possible, were compared with other domestic animals emphasizing species differences. Information obtained from gross dissection of embalmed camel heads was correlated with latex injected vascular casts, as well as venographs. Although the disposition of the dural sinuses, in general, was similar to those of other domestic animals, they were somewhat complex in the camel. An important venous flow mechanism which functions in the thermoregulation of the brain in the camel was described. The venous drainage of the nasal cavity and its surrounding areas had five connections with the ophthalmic plexus and the cavernous sinus: (1) the infraorbital vein----ophthalmic plexus; (2) the medial superior palpebral vein----ophthalmic plexus; (3) the medial inferior palpebral vein----ophthalmic plexus; (4) the angularis oculi----frontal----supraorbital----dorsal external ophthalmic----emissary vein of the foramen orbitorotundum----cavernous sinus; and (5) the deep facial vein----ventral external ophthalmic----emissary vein of the foramen orbitorotundum----cavernous sinus.  相似文献   

6.
The anatomy of the dura mater's venous sinuses is important in the veterinary clinical and surgical area, for cranial procedures and interventions of wild animals, in addition to assisting in the management of neurological diseases, which can prevent serious complications. The macroscopic anatomy of the venous sinuses of the dura mater of Alouatta belzebul was studied. Five adult specimens, males and females, were dissected and fixed in 10% formaldehyde solution. In the dura mater of the Alouatta belzebul, nine venous sinuses were observed, being them dorsal sagittal sinus, ventral sagittal sinus, transverse sinus, straight sinus, sigmoid sinus, temporal sinus, parietal sinus, basilar sinus and cavernous sinus, with morphological similarities in origin, path and destination of blood flow to the internal jugular vein, assisting in the venous drainage function of the brain in this species. These data are similar to those found in other species of non-human and human primates such as Saimiri sciureus, Sapajus libidinosus and Homo sapiens. Of the venous sinuses observed, the cavernous sinus was of considerable clinical and surgical importance in Alouatta belzebul due to its topographic arrangement next to the internal carotid artery and pituitary gland, data that corroborate Sapajus libidinosus, Macaca fascicularis, Macaca mulatta, Papio ursinus, Cercopithecus pygerithrus and Galago senegalensis. In this context, the knowledge of the macroscopic anatomy of the venous sinuses of the dura mater may contribute to the role of veterinarians in less invasive surgical procedures in non-human primates such as Alouatta belzebul and other mammals.  相似文献   

7.
The veins of the corpus cavernosum penis (ccp) were examined in 34 calves aged one to three weeks, 38 calves aged three to four months, five bulls aged 10 to 14 months and six bulls aged two-and-a-half to five-and-a-half years. Shortly after birth, the cavernous spaces of the ccp within the body of the penis drain into the dorsal venous system. The veins increase in size up to three to four months old, but by 10 to 14 months they have regressed markedly, both in numbers and in size. In normal bulls, over two-and-a-half years, there is no venous drainage of the ccp within the body of the penis. The thickness of the tunica albuginea does not seem important in determining the location of the veins that traverse it to drain the ccp or in facilitating the development of venous drainage during the first three or four months of post natal life. These findings are discussed in relation to impotence associated with distal venous drainage of the ccp in young and adult bulls.  相似文献   

8.
Gross and histologic features of the rostral epidural rete mirabile (carotid rete) and the cavernous sinus in one-humped camels were studied. It was evident that the branches of the carotid rete share a common tunica adventitia with the veins of the cavernous sinus. Transmission electron microscopy of the rostral epidural rete mirabile and the cavernous sinus revealed gap junctions in endothelial cells lining the walls of the arterial rete branches and veins. The internal elastic lamina of rete branches were fenestrated. Some of these structural features could facilitate countercurrent heat exchange between the rete branches and the venous plexus of the cavernous sinus to regulate brain temperature.  相似文献   

9.
Computed tomographic anatomy of the normal canine ethmoid region using both transverse and dorsal imaging plane is described. In the transverse plane, the cribriform plate appears as an irregular heart-shaped to rectangular structure that is generally visualized on no more than one to two contiguous 4-mm slices. In the dorsal plane, the cribriform plate appears as a discrete "V"-shaped structure and can be visualized on four to five contiguous slices. Successful visualization of the cribriform was less dependent on patient positioning for the dorsal plane imaging studies. Computed tomographic findings in four dogs with chronic nasal disease and complete postmortem examination of the ethmoid region indicate that the dorsal imaging plane allows a more accurate assessment of cribriform plate involvement than the transverse imaging plane.  相似文献   

10.
11.
Priapism in a stallion with generalized malignant melanoma   总被引:2,自引:0,他引:2  
A Thoroughbred stallion developed priapism that was unresponsive to medical treatment and lavage of the corpus cavernosum penis with heparinized 0.9% NaCl solution. Three weeks after onset of priapism, the penis was firm and noncompliant, and penile pain sensation and ability to retract the penis were lost. Ultrasonography confirmed thrombosis of the corpus cavernosum penis. The stallion was euthanatized because of poor prognosis for return to breeding soundness. Necropsy revealed enlargement of numerous lymph nodes. The dorsal penile nerves were demyelinated distal to the crura of the penis. A diagnosis of generalized malignant melanoma was made; however, neither metastasis to the vertebral canal nor compression of spinal nerve roots as they exited the vertebral foramen was found. Priapism is a persistent erection without sexual arousal and is initially unassociated with penile paralysis, but if prolonged, leads to irreversible venous occlusion where collecting veins join the cavernous spaces. Damage to the dorsal penile nerves may explain the long-term penile paralysis and loss of sensation that accompanied priapism in this stallion. Priapism unassociated with the use of phenothiazine-derivative tranquilizers is uncommon in horses.  相似文献   

12.
A method for systematic examination of the livers was developed, based on identification of the hepatic and portal veins in sixteen dogs. The right medial, quadrate, left medial and lateral hepatic veins and the hepatic branches of the portal veins were easily located with the dog in dorsal recumbency. The right lateral and caudate hepatic veins were identified more easily from the right side with the transducer positioned between the ninth to the eleventh intercostal spaces. Visibility was affected by the fullness of the stomach but this effect could be minimized by changing the position of the transducer to select a more suitable anatomical approach. Identification of the two systems depended on their echogenicity, the anatomical position of the main branches and their pattern of distribution. As in humans, the portal veins were in general, more echogenic than the hepatic veins and the hepatic veins could be traced from their junctions with the caudal vena cava. Identification of the branches of the hepatic and portal veins was complicated by the anatomical shape, the nutritional status and respiratory stage of the animal. A systemic approach based on a knowledge of the distribution patterns produced by the hepatic and portal veins ensures that all liver lobes are identified and all important structures are assessed.  相似文献   

13.
The system of the paranasal sinuses morphologically represents one of the most complex parts of the equine body. A clear understanding of spatial relationships is needed for correct diagnosis and treatment. The purpose of this study was to describe the anatomy and volume of equine paranasal sinuses using three‐dimensional (3D) reformatted renderings of computed tomography (CT) slices. Heads of 18 cadaver horses, aged 2–25 years, were analyzed by the use of separate semi‐automated segmentation of the following bilateral paranasal sinus compartments: rostral maxillary sinus (Sinus maxillaris rostralis), ventral conchal sinus (Sinus conchae ventralis), caudal maxillary sinus (Sinus maxillaris caudalis), dorsal conchal sinus (Sinus conchae dorsalis), frontal sinus (Sinus frontalis), sphenopalatine sinus (Sinus sphenopalatinus), and middle conchal sinus (Sinus conchae mediae). Reconstructed structures were displayed separately, grouped, or altogether as transparent or solid elements to visualize individual paranasal sinus morphology. The paranasal sinuses appeared to be divided into two systems by the maxillary septum (Septum sinuum maxillarium). The first or rostral system included the rostral maxillary and ventral conchal sinus. The second or caudal system included the caudal maxillary, dorsal conchal, frontal, sphenopalatine, and middle conchal sinuses. These two systems overlapped and were interlocked due to the oblique orientation of the maxillary septum. Total volumes of the paranasal sinuses ranged from 911.50 to 1502.00 ml (mean ± SD, 1151.00 ± 186.30 ml). 3D renderings of equine paranasal sinuses by use of semi‐automated segmentation of CT‐datasets improved understanding of this anatomically challenging region.  相似文献   

14.
Diseases of paranasal sinuses and nasal passages in horses can be a diagnostic challenge because of the complex anatomy of the head and limitations of many diagnostic modalities. Our hypothesis was that magnetic resonance (MR) imaging would provide excellent anatomical detail and soft tissue resolution, and would be accurate in the diagnosis of diseases of the paranasal sinuses and nasal passages in horses. Fourteen horses were imaged. Inclusion criteria were lesions located to the sinuses or nasal passages that underwent MR imaging and subsequent surgical intervention and/or histopathologic examination. A low field, 0.3 tesla open magnet was used. Sequences in the standard protocol were fast spin echo T2 sagittal and transverse, spin echo T1 transverse, short‐tau inversion recovery (STIR) dorsal, gradient echo 3D T1 MPR dorsal (plain and contrast enhanced), spin echo T1 fatsat (contrast enhanced). Mean scan time to complete the examination was 53 min (range 39–99 min). Lesions identified were primary or secondary sinusitis (six horses), paranasal sinus cyst (four horses), progressive ethmoid hematoma (two horses), and neoplasia (two horses). The most useful sequences were fast spin echo T2 transverse and sagittal, STIR dorsal and FE3D MPR (survey and contrast enhanced). Fluid accumulation, mucosal thickening, presence of encapsulated contents, bone deformation, and thickening were common findings observed in MR imaging. In selected horses, magnetic resonance imaging is a useful tool in diagnosing lesions of the paranasal sinuses and nasal passages.  相似文献   

15.
The present work aimed to describe the normal computed tomography (CT) and cross‐sectional anatomy of the nasal and paranasal sinuses in sheep and to correlate these features with the relevant clinical practices. Twenty apparent healthy heads of Egyptian native breed of sheep (Baladi sheep) of both sexes were used for studying these sinuses. CT images and their closely identical cross sections of the same head were selected and serially labelled in a progression from the rostral nasal region to the caudal aspect of the head using cheek teeth as landmarks. The current investigation reported seven sinuses in sheep, including maxillary, frontal, lacrimal and sphenoidal as paranasal, as well as dorsal and middle conchal and ethmoidal as nasal with unnoticeable palatine and ventral nasal conchal sinuses. The boundaries, extension, structure and communications of these sinuses were fully described. The current study provided anatomical guidelines for surgical interference in the frontal and maxillary sinuses during trephination, dehorning and sinuscopy. Also, an acceptable anatomical explanation was reported in this study for the high incidence of maxillary sinusitis than other sinuses. CT and cross‐sectional anatomy could be used as helpful database for diagnosis and clinical interference of the nasal and paranasal sinuses in sheep.  相似文献   

16.
利用Pie Data SC-400型超声扫描仪,对12头临床健康牛进行肝胆超声断层扫描的反复实验。结果:牛肝脏可在右侧第8~12肋间显示,呈均匀的弱回声影像,肝下缘切面轮廓为锐角的楔状图像,肝壁面及脏面整齐、清晰:门静脉和肝静脉能在多数牛的第10~12肋间显示,并可根据其管壁回声强弱等加以分辨;胆囊多在右侧第11或10肋间探到,为边缘光滑整齐、轮廓清晰的类三角形或椭圆形无回声液性暗区。并测定了试验  相似文献   

17.
The nasal venous blood may be directed through the facial vein into the systemic circulation or through the frontal vein into the venous cavernous sinus of the perihypophyseal vascular complex, where hormones and pheromones permeate from the venous blood into the arterial blood supplying the brain and hypophysis. The present study was designed to determine the effect of noradrenaline (NA) on the tension of the nasal, frontal and facial veins of cycling gilts, and influence of ovarian steroid hormones on NA-mediated contractile reactivity. Additionally, the enzyme dopamine-beta-hydroxylase catalysing the conversion of dopamine to noradrenaline (DbetaH) was immunolocalized in these vessels. Among three studied veins, the frontal proximal vein, that fulfill a key role in the supply of the nasal venous blood into the venous cavernous sinus, reacted to NA most strongly (P < 0.001) and this reaction was weaker in the periestrous period than in luteal phase (P < 0.001). Inversely, the reaction to NA of the facial proximal vein, that carry blood to the peripheral circulation, was stronger in the periestrous period than in luteal phase (P < 0.05). P4, E2 and T significantly lowered NA-mediated tension of the frontal proximal vein during the periestrous period (P < 0.001), while in the luteal phase P4 might antagonize relaxing effect of E2 to this vessel. The result suggests that supply of the nasal venous blood into the venous cavernous sinus is greater during the periestrous period than during the luteal phase. DbetaH was clearly expressed in the muscular layer of the isolated superficial nasal and facial veins of gilts in both studied stages of the estrous cycle. We suggest that the reactivity of the superficial veins of the nose and face to NA combined with the previously demonstrated reactivity of these veins to steroid ovarian hormones and male steroid pheromones may regulate the access of priming pheromone androstenol (resorebed in the nasal cavity) to the brain of gilts during periestrous period via humoral local destination transfer.  相似文献   

18.
The structure of paranasal sinuses in cattle is difficult to understand due to its complexity, age-related changes, and insufficient published data. In this prospective, anatomic study, we described the anatomy of the paranasal sinuses in the Holstein cow using computed tomography (CT) and cross-sectional anatomic slices. Twelve healthy adult Holstein cow heads were used for this study. The heads were scanned using CT, and frozen anatomical sections were taken. The locations, borders, and relationships of the paranasal sinuses were defined on the anatomical sections and CT images. The paranasal sinuses on each side of the head consisted of conchal (dorsal, middle, and ventral), maxillary, lacrimal, palatine, frontal, sphenoid sinuses, and ethmoidal cells. The frontal sinus pneumatized all bones surrounding the cranial cavity, except for the ethmoidal and body of basisphenoid bones. The sphenoid and ventral conchal sinuses were the most asymmetrical, and the middle conchal sinus was the simplest. The ventral conchal sinus was detected in eleven animals, one of which was unilateral. This sinus communicated with the middle nasal meatus (13/21) and ventral nasal meatus (8/21). Findings can be used as background for interpreting CT studies of cattle with clinical signs of sinonasal region diseases. Future cross-sectional radiological and reconstructive anatomical studies and investigation of the postnatal development of related structures in cattle are needed.  相似文献   

19.
REASONS FOR PERFORMING STUDY: Disorders of the equine sphenopalatine sinus, including empyema and neoplasia, have been reported to cause damage to cranial nerves II and V. However, the clinical anatomy of these sinuses is not well described in horses. OBJECTIVE: To examine the anatomy of the sphenopalatine sinuses in a range of equidae and, in particular, to examine the relationship of these sinuses to adjacent major nerves and vessels. METHODS: The anatomy of the sphenoidal and palatine paranasal sinuses was examined in 16 equidae, primarily using transverse skull sections. Relevant structures were documented and photographed. RESULTS: There was much variation between individual horses in sphenopalatine sinus anatomy. The sphenoidal sinuses were small in young horses and appeared to become larger and more complex with age. Variation was present in the extent that the sphenopalatine sinus extended into the basisphenoid bone. The septum dividing left and right sphenoidal sinuses was frequently not midline, but was intact in all cases. The sphenoidal and palatine sinuses communicated in most horses. In such cases, what could accurately be termed the (combined) sphenopalatine sinuses usually drained directly into the caudal maxillary sinuses. Additionally, in 5 out of 16 cases, some compartments of the sphenoidal sinus also drained into the ethmoidal sinus. The dorsal and lateral walls of the sphenoidal sinus were very thin and directly adjacent to cranial nerves II, III, IV, V and VI and major blood vessels. CONCLUSIONS: The equine sphenoidal and palatine sinuses are very variable in their anatomy, but are always in close proximity to multiple cranial nerves and major blood vessels. POTENTIAL RELEVANCE: Many cranial nerves and blood vessels could be damaged with disorders involving the sphenopalatine sinus, potentially causing major and variable neurological syndromes, haemorrhage and extension of sepsis.  相似文献   

20.
The objective of the study was to determine whether the local permeability of luteinizing hormone-releasing hormone (LHRH) from the venous blood of the perihypophyseal cavernous sinus into the arterial blood of the carotid rete, supplying the brain and hypophysis in gilts, depends on the day of the estrous cycle, as well as to determine whether this transfer exists when LH concentration in the blood is reduced (the experimental short-loop negative feedback for LH secretion after estradiol injection in ovariectomized gilts). Experiments were conducted on isolated gilt heads with necks, on chosen days of the estrous cycle (n = 40), and on previously ovariectomized gilts treated with estradiol benzoate (EB) (n = 5) or corn oil (n = 3). After exsanguination, the gilt heads with necks were disarticulated and about 30–45 min later were supplied with autologous, oxygenated, and heated blood at a stable blood flow and pressure through the left carotid artery for 30 min. 125I-LHRH was infused into both cavernous sinuses through the cannulated angularis oculi veins for 5 min. After 125I-LHRH infusion, radiolabeled LHRH was found (P < 0.001) in arterial blood taken from the carotid rete through the open right carotid artery in all animals used in the experiment: on Days 1–2 (six gilts), on Days 12–14 (seven gilts) of the estrous cycle, and in five ovariectomized gilts during negative feedback for LH surge (40 hr after EB). No significant radioactivity of 125I-LHRH was found in the arterial blood on Days 3–5 (n = 6), 9–11 (n = 4), and 15–21 (n = 17) of the estrous cycle. A very low level of radioactivity was found in the ovariectomized control group after the injection of corn oil (n = 3). These results provide evidence for the permeability of LHRH from the venous to the arterial blood and its retrograde transport with the arterial blood to the hypophysis and brain, after the ovulation period (Days 1–2) and on Days 12–14 of the estrous cycle. This suggests that a close relationship exists between the day of the estrous cycle and LHRH permeability from the venous to the arterial blood in the perihypophyseal cavernous sinus—the carotid rete complex in gilts—and that this mechanism may be included in a short-loop feedback for LHRH secretion.  相似文献   

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