Vertebral artery (VA), the main element of the posterior brain circulation, has many anatomical variations which generally were widely investigated. However, available data vary in wide ranges, reflecting very different sample sizes, lack of data about left-right or sex differences, and about possible ethnic, regionally specific or genetic differences. Certain new findings suggest possible involvement of some environmental factors in VA variations. Accurate anatomical data about VA variations in different regions of the world, including Balkans countries, are still lacking. Therefore we investigated morphological variability of VA origin and its entrance level into cervical transverse foramina in population of Republika Srpska (Bosnia and Herzegovina), including data about the sex and side. Anatomy of VA was investigated in 112 persons (224 arteries) of both sexes (58 males, 54 females; age 19 - 83 years), using 64-slice CT scanner. Origin of VA from subclavian artery (SCA) we found in 95.08% of arteries (52 males, 49 females). Only in one male (0.45 %) left VA and left SCA had an specific origin from aortic arch (AA), which we named as an "common area of origin". All other observed variations in origin were only of left VA, originating from AA in 4.47 % (5 males, 5 females). Left VA Most often (usual) entrance level into transverse foramen we found at C6 (87.5%), followed by C5 (8.93 %), C4 (3.12 %), and in one case at level C7 (0.45 %). Entry levels at C5 both, on right and on the left side, were 3 times more frequent in males than in females. Wide ranges of differences between the data we obtained on a sample in Republika Srpska (Bosnia and Herzegovina) and the data from many other studies require further and wider investigations.

Background: The available anatomical data about diameters of inflow vessels to the circle of Willis reflect various diagnostic and imaging methods used, sample sizes, levels of measurements, and lack of possible specific ethnic, regional or genetic data. Additionally, the data are often without distinctions about left-right or sex. Materials and methods: Therefore, using computed tomography angiography (CTA) we investigated diameters of internal carotid (ICA) and vertebral (VA) arteries in 70 adult persons (28-75 years) of both sexes (34 males and 36 females), at predefined cervical parts of ICA (2 cm above carotid bifurcation) and of VA (5 mm before VA penetrated the dura). Results: Sex differences were expressed as highly significant larger diameters of left VA (LVA) in males (3.49 mm) than in females (3.00 mm), and as significantly larger diameters of right VA (RVA) in males (3.20 mm) than in females (2.82 mm), as well as of right ICA (RICA) diameters in males (5.04 mm) than in females (4.56 mm), but without such difference for left ICA (LICA) between males (4.82 mm) and females (4.60 mm). Intrasex (in males or in females) left-right differences of ICA and VA diameters were not significant. Significant positive correlations were found in females between RICA and RVA, and in males between RICA and LICA. Calculated mean sum of ipsilateral diameters of right arteries (RAA = RICA + RVA) was in males 8.25 mm, in females 7.38 mm, and of left arteries (LAA = LICA + LVA) was in males 8.31, and in females 7.60 mm, without statistically significant difference between RAA and LAA, neither in males, nor in females. Statistically highly significant larger sums of diameters were in males than in females for both, RAA and LAA. Conclusions: Our findings, as the first data about diameters of ICA and VA systematically obtained by CTA in the population of western Balkans, suggest that in the studies of these diameters is absolutely necessary to analyse separately the data for sex, and to use defined standard levels.

Background: We investigated diameters of prevertebral-V1, and atlantic-V3 parts of extradural segment of vertebral artery (VA). Variable results from the literature about VA diameters reflect variety of diagnostic and imaging methods, various sample sizes, different levels of measurements, and lack of possible specific ethnic, regional or genetic data. Additionally, the data are often without distinctions of left-right or of sex. Materials and methods: For this computed tomography (CT) angiographic study 91 adult people (182 VAs) of both sexes (47 males and 44 females) and of age between 33 and 75 years were selected. Diameters were measured at fixed predefined points of VA, marked as inferior (A) point (at V1 part in region of VA origin), as middle (B) point (the end of V1 part), and superior (C) point, at V3 part-5 mm before VA penetrated the dura. Inferior (A) and middle (B) points actually represent locations at beginning (A) and at terminal (B) regions of V1 part of VA, and superior point C represents terminal part of V3. Results: In total sample ipsilateral (both left [L] and right [R] sided) diameters on investigated levels of VA showed progressive and highly significant decreases. The mean values were on the right side at point A-3.63 mm, at B point-3.31 mm, and at C point-3.08 mm. On the left side, mean values were at point A-3.76 mm, at B point-3.50 mm, and at point C-3.21 mm. Pattern of increasing sex differences in diameters of VA, was ranging from no differences (point A), trough significant (point B), to highly significant differences (point C). For inferior point (A) we did not find significant differences in VA diameters between males

Kratak sadržajUvod. Ektraskeletalni Ewing-ov sarkom (EES) je neuroektodermalni tumor koštanog porijekla, koji se najčešće javlja u drugoj deceniji života. EES je izuzetno rijedak tumor. Cilj rada je prikazati RTG i CT nalaze kod rijetkog oblika torakalne lokalizacije EES kao što je slučaj kod našeg pacijenta.Prikaz bolesnika. U radu predstavljamo EES porijekla lijeve visceralne pleure, koji je dijagnostikovan kod dvadesetjednogodišnjeg muškarca, sa neodređenim bolom u ramenu. Inicijalno je načinjena radiografija grudnog koša, na kojoj je uočena pleuralna efuzija i jasno ograničena mekotkivna masa duž lijevog lateralnog torakalnog zida. Neposredno urađena je kompjuterizovana tomografija grudnog koša, koja jasnije prikazuje difuznu distribuciju multiplih nodularnih mekotkivnih zadebljanja pleure lijevog hemitoraksa. Histološki je dokazan EES visceralne pleure.Zaključak. EES -primitivni neuroektodermalni tumor je rijedak tumor koji treba razlikovati od drugih tumora malih okruglih ćelija na osnovu njegove morfologije i laboratorijskih nalaza. Iako je ekstremno rijedak , EES treba da bude uzet u obzir u diferencijalnoj dijagnozi primarnih tumora zida grudnog koša.Ključne riječi: ektraskeletalni Ewing-ov sarkom, tumori torakalnog zida