A reminder of the anatomy of the recurrent artery of heubner.

Previous accounts of the recurrent artery of Heubner show serious inconsistencies concerning the origins, dimensions and numbers of the artery. In the present study, based on 54 (38 male, 16 female) human autopsy brains the common type of the recurrent artery of Heubner was present bilaterally in 46 cases (85.2%), while in 6 (11.1%) cases it was present only on one side (4 on the right, 2 on the left). Unilateral vessels were seen only in the male autopsy brains. The recurrent artery of Heubner could not be identified in 2 brains (3.7%). Multiple Heubner arteries were not observed in the present study. No gender differences were observed regarding the origin and dimensions of the recurrent artery of Heubner. 76 recurrent arteries of Heubner arising from the junction of the anterior cerebral artery (ACA) and anterior communicating artery (ACoA) (79.2%) had a mean diameter of 0.66+/-0.11 mm. In 14 arteries the artery derived from the A2 segment of the ACA (14.6%) and the mean diameter was 0.66+/-0.17 mm; in 6 arteries it originated from the A1 segment of the ACA (6.2%) and the mean diameter was 0.47+/-0.15 mm. The average diameter was calculated as 0.67+/-0.12 mm and ranged between 0.40 and 0.90 mm, irrespective of sex or side. A detailed anatomical knowledge of the recurrent artery of Heubner is important when considering vascular surgery in this area.

Changing diameters of cerebral vessels with age in human autopsy specimens: possible relationships to atherosclerotic changes.

AIMS/OBJECTIVES: It has been previously recognized that the anatomy of arterial bifurcations influences blood flow and has a significant role in the development of vascular disease. MATERIAL AND METHODS: In the present study, we measured the average diameters of the internal carotid (ICA), anterior cerebral (ACA), and middle cerebral arteries (MCA) in autopsy cases. We also calculated the outflow to inflow area ratios for four distinct age groups and for each gender, using 33 adult autopsies and 7 fetuses. RESULTS: The area ratios decreased with age in both male and female samples. The decrease in the male (30%, p<0.05) was greater than the decrease for the female (17%, p > 0.05). The average diameter of the ACA, MCA and ICA of both female and male cases increased up to the 25-44 age group, decreased for the 45-64 age group, with a second increase above the age of 65. CONCLUSIONS: The decrease in the area ratios and the pattern of changes of the dimensions of the cerebral vessels with age are useful to examine the causal relationships of these pathologic conditions and raises novel questions about age and gender differences in the structure of the intracranial vessels.

Morphometric measurements of the caudal cranial nerves in the petroclival region.

OBJECTIVE: The dural zone of entry or exit of the caudal cranial nerves in the petroclival region does not have a constant localization. The present study aimed to measure the clival length, the distances between cranial nerve dural openings and the distance of cranial nerves from the mid-clival line in 30 human autopsy cases. MATERIAL AND METHODS: Thirty autopsy specimens (8 female, 22 male) from persons aged between 20-76 years (mean age 38.9 years) were studied. Autopsies with intracranial lesions were not included in the study. RESULTS: The average distances between the right and left dural openings of caudal cranial nerves in the petroclival region were as follows (mean+/-sd): trigeminal, 32.17+/-5.41 mm; abducent, 20.04+/-3.23 mm; facial and vestibulocochlear, 50.97+/-5.86 mm; glossopharyngeal, vagus, accessory, 41.59+/-6.46 mm and hypoglossal 26.8+/-4.33 mm. The measurements of the distances of the cranial nerve exits to the mid-clival line showed considerable asymmetries for the left and right trigeminal nerves. Furthermore, the distances between the trigeminal and the abducent nerves on the right and left differed significantly (p<0.029). The average distance between these two cranial nerves on the left was 8.44+/-3.66 mm and on the right was 7.31+/-2.41 mm. In addition, the average clival length was 56.96+/-5.91 mm (range: 42-71 mm). CONCLUSIONS: Most of the surgical procedures performed in this area are to remove tumors which significantly modify the local anatomy. Knowledge of morphometric variations can increase the success of cranial nerve preservation during surgical procedures of the posterior cranial fossa.

The anatomy of the carotico-clinoid foramen and its relation with the internal carotid artery.

The carotico-clinoid foramen is the result of ossification either of the carotico-clinoid ligament or of a dural fold extending between the anterior and middle clinoid processes of the sphenoid bone. It is anatomically important due to its relations with the cavernous sinus and its content, sphenoid sinus and pituitary gland. In this study the ossification state of the carotico-clinoid ligament, the diameter of the internal carotid artery and the carotico-clinoid foramen has been studied on 50 autopsy cases. Of the 100 carotico-clinoid foramina examined, in 27 sides (15 right, 12 left) the carotico-clinoid ligament was completely ossified, in 18 sides (9 right, 9 left) the carotico-clinoid ligament was incompletely ossified and in 55 sides (26 right, 29 left) it was a ligamentous structure. The correlation of the dimensions of the carotico-clinoid foramen and the internal carotid artery showed no statistical significance, except between the carotico-clinoid foramen with a fibrous carotico-clinoid ligament and the internal carotid artery on the right side (p=0.007, r=0.51). The existence of a bony carotico-clinoid foramen may cause compression, tightening or stretching of the internal carotid artery. Further, removing the anterior clinoid process is an important step in regional surgery; the presence of a bony carotico-clinoid foramen may have high risk. Therefore, detailed knowledge of the type of ossification between the anterior and middle clinoid processes can be necessary to increase the success of regional surgery.

Trifurcation of the left common carotid artery: a case report.

During dissection of the carotid triangle, a carotid trifurcation was encountered. The left common carotid artery gave off three terminal branches: external carotid, internal carotid, and occipital arteries. The level of trifurcation was 35 mm above the superior margin of the thyroid cartilage. Further, the superior thyroid artery arose from the common carotid artery instead of the external carotid. Herein, we describe the detailed anatomical features of the variant branching pattern of the left common carotid artery and its clinical implications.

A variation of coeliac trunk.

The anatomical variations of the coeliac trunk are due to developmental changes in the ventral splanchnic arteries. This report describes a case in which the left inferior phrenic artery and left gastric artery arose from the long coeliac trunk (4.3 cm.) via a common trunk. The arterial variations, like other anatomical variations, cannot be ignored during the operative procedures in abdomen. Therefore the different forms of variations concerning the coeliac trunk should be kept in mind during both surgical and non-surgical evaluations.