Morphologic characteristics of sacra associated with assimilation of the last lumbar vertebra.

BACKGROUND: The impact of lumbosacral transitional states on biomechanics of load transmission between the spine and the legs has been sporadically reported. The aims of the study were to identify morphostructural alterations of sacra associated with assimilation of the last lumbar vertebra and to analyse them in the light of their biomechanical impact. MATERIALS AND METHODS: Linear dimensions of sacrum, its body and base and articular surfaces were measured in 31 normal and 41 transitory sacra. Nineteen sacra presented articular and 22 osseous fusion of the last lumbar vertebra. Measured parameters were compared between normal sacra and the two variations of transitory sacra. RESULTS: Sacra with articular fusion of the last lumbar vertebra showed more pronounced concavity of the sacral curvature and wider than long sacral bodies. The first sacral segment was modified, broaden, ventrally wider and elevated. Almost the whole segment bore at its sides auricular surfaces. Very small portion of the segment was non-articular with less pronounced wedging. Sacra with osseous fusion of the last lumbar vertebra showed similar concavity of the sacral curvature as normal sacra, but longer than wide sacral bodies. The ventral sloping half of the newly formed first segment bore auricular surfaces. The non-articular part was enlarged with pronounced wedging. CONCLUSIONS: The term "sacralisation" includes both types of transitory sacra with mutually different morphostructural characteristics in contrast to the normal sacra. Analysis of these morphologic variations may help in understanding the different biomechanical properties and patterns of load transmission.

Anatomy of coronary sinus ostium.

BACKGROUND: The coronary sinus is the main cardiac vein and it has become a clinically important structure especially through its role in providing access for different cardiac procedures. MATERIALS AND METHODS: The study was carried out on 100 randomly selected adult human cadaver hearts fixed in 10% formalin. The transverse and craniocaudal diameters of the coronary sinus ostium (CSO) were directly measured. The presence of the Thebesian valve was noted and the anatomical details of the valve were documented in each case in terms of the shape and extent of coverage of the CSO. RESULTS: Considerable variations in the diameter of the CSO were observed. The mean craniocaudal diameter of the CSO was 8.1 ± 1.51 mm, and the mean transverse diameter was 7.67 ± 1.72 mm. Heart specimens without Thebesian valve tended to have larger ostia. The mean craniocaudal diameter and the mean transverse diameter of the CSO were statistically larger in the specimens without Thebesian valves (p = 0.000 and p = 0.001, respectively). CONCLUSIONS: The Thebesian valves were observed in 86 hearts, and a wide variety of their morphology was seen. The majority of the Thebesian valves were semilunar in shape (74.42%). The extent to which the valve covered the ostium was variable, including remnant valves that covered < 15% of the CSO (35%), and valves that were large and covered at least 75% of the CSO (22.09%). In 3 specimens the valve completely occluded the ostium.

Morphological characteristics of the superior cerebellar artery.

With the introduction of new techniques in diagnostic and interventional radiology and progress in micro neurosurgery, accurate knowledge of the brain blood vessels is essential for daily clinical work. The aim of this study was to describe the morphological characteristics of the superior cerebellar artery and to emphasize their clinical significance. In this study we examined radiographs of 109 patients who had CT angiography at the University Clinic for Radiology in Skopje, R. Macedonia. This study included 49 females and 60 males, ranging in age from 27 to 83 years; mean age 57.4 ± 11.8 years. In 105 patients SCA arose from the basilar artery on both sides as a single vessel. In two patients SCA arose as a duplicate trunk from the basilar artery. We found unilateral duplication on the right SCA in one patient, and bilateral duplication in one patient. In two patients was noticed origin of the SCA from PCA as a single trunk from adult type of the PCA. Through knowledge of the anatomy and variations of SCA is important for clinicians as well as basic scientists who deal with problems related to intracranial vasculature in daily basis for save performance of diagnostic and interventional procedures.

Morphological characteristics of the first part of the vertebral artery.

Because of their anatomical localization, vertebral arteries were neglected in research for a long period of time. Vertebral arteries are responsible for about 30% of the brain blood supply. The aim of this study was to examine the vertebral artery's course in the first segment, and to define the anatomic variations and percentage of their appearance in the adult population using CT angiography. The data derived from this study may find useful application in a wide range of medical fields, such as anatomy, radiology and surgery. For that purpose during a 6-month period we examined 30 patients with CT angiography. The origin of the vertebral artery in all 30 patients was from the subclavian artery. The diameter of the left vertebral artery was from 1.6-5.20 mm., average 3.35 mm. The diameter of the right vertebral artery was from 1.64-5.40 mm., average 3.19 mm. Hypoplasia of the vessel was found in four patients. We found no aplasia of the vessel in this series. A contorted course was found in 12 (40%) patients. In all 30 (100%) patients the vertebral artery entered the foramen transversum at the level of the sixth cervical vertebra. Although the incidence of anatomical variations is rare, their presence is significant in the diagnostic and surgical procedures in the head and neck region. Insufficient knowledge can lead to serious iatrogenic injures.

Basilar artery fenestration.

The posterior circulation of the brain constitutes the vertebrobasilar system and its branches, which are responsible for about 30% of the brain's blood supply. The aim of this study was to describe the anomalies of the basilar artery, especially fenestrations. For that purpose, we examined 50 patients with computed tomography (CT) angiography during an 8-month period. In the CT reports of 2 (4%) patients of the 50 analysed, fenestration was found at the proximal basilar trunk. The two fenestrations in our series were not associated with aneurysms. No collateral branches originated from the two limbs of the fenestration. In conclusion, basilar artery fenestrations are a rare finding. The data derived from this study are useful teaching material for anatomists, and for the radiologists and neurosurgeons they are important for diagnostic and intervention procedures such as CT, magnetic resonance imaging, angiography, and surgical and endovascular procedures.