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.

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 diameters of common carotid artery and its branches in newborns.

The common carotid artery (CCA) bifurcation is of clinical importance due to its vascular access site for intravascular intervention. Additionally, it is also one of the most common sites of atherosclerotic plaque formation. There are numerous studies on the diameters of CCA, internal carotid artery (ICA), and external carotid artery (ECA) in adults, but few studies on newborns. Cadaver and angiographic studies have shown dimensional variations in the carotid arteries within/between individuals and also between different sexes. It is well known that the initial lesions of atherosclerosis begin very early in fetal life. Therefore, it is important to know the anatomical details of the CCA and its branches. In the present study, the neck regions of 20 (11 males and 9 females) fixed newborn cadavers were dissected. The CCAs were cut below the bulb of the carotid bifurcation further; ICA and ECA were cut above the bulb of the carotid bifurcation. The internal diameters of the CCA, ICA, and ECA were measured using a light microscopy. ECA/CCA, ICA/CCA, ICA/ECA ratios, and outflow to inflow area ratio were calculated. The mean outflow to inflow area ratio was 1.14+/-0.28. Our results highly correlated with the defined optimal ratio (1.15). The ECA/CCA, ICA/CCA, and ICA/ECA ratios were 0.78+/-0.12, 0.71+/-0.13, and 0.93+/-0.16, respectively. There were no statistically significant differences between male and female and also between right and left sides. These findings are of importance in understanding the anatomy of carotid artery during newborn period.