Considerations on the morphology of the thyroid ima artery.

PURPOSE AND BACKGROUND: Detailed knowledge of the thyroid ima artery is essential for surgeons consequently we conducted an analysis investigating the arterial vasculature of the thyroid gland in 290 cases by dissection of formalin-fixed cadavers and by studying computed tomography angiographies. METHODS: Our study was conducted on 82 cases obtained from the dissection of formalin-fixed cadavers while 208 cases were computed tomography angiographies. The following aspects were observed: the frequency of the thyroid ima artery, its origin, course, and diameter. All were studied, comparing right to left and according to sex. RESULTS: Following the study of thyroid gland vasculature on a number of 290 cases, the thyroid ima artery was discovered in 16 cases (5.52% of cases), from which 3.45% of cases were in male subjects, and 2.07% of cases in female subjects. Of these, 4.14% of the total cases were left thyroid ima artery, and 1.38% of cases were on the right, found only in female subjects. In 5.17% of the total cases, the thyroid ima artery originated from the aortic arch, of which 3.45% were in the male sex and 1.72% were in the female sex. In one case only (0.35%) in the female sex did the thyroid ima artery originate from the brachiocephalic trunk. In 2.76% of cases, the thyroid ima artery existed with a left-sided inferior thyroid artery originating from the subclavian artery, either directly or from a thyrocervical trunk. CONCLUSIONS: The thyroid ima artery has proven to be one of the highly variable arteries in terms of its presence and origin and the knowledge surrounding it is useful for surgical interventions.

Considerations on the origin of the inferior thyroid artery emerging from the subclavian artery determined by CT examination.

PURPOSE AND BACKGROUND: The specialized literature has a low degree of information regarding the origin of the inferior thyroid artery (ITA). Our study was performed on computed tomography angiographies (CTAs), and the following aspects were observed: the origin of the ITA from the subclavian artery (SCA) or thyrocervical trunk (TCT), taking note of the distance of the origin of the ITA in relation to the origin of the SCA or the corresponding TCT, as well as the origin of the ITA, comparing right to left and according to gender. METHODS: Our study was realized on a total of 108 ITA (64 on the right side and 44 on the left, with 48 in male subjects and 60 in females), analyzed on CTA. RESULTS: From the 108 arteries, we found the origin of ITA directly from the SCA in 31.48% of cases, and in 68.52% from the TCT. The distance between the origin of the right SCA and the origin of the corresponding ITA, was between 29.1 and 53.1 mm, while on the left side, the same distance was between 43.7 and 68.1 mm. The distance between the right TCT and the origin of the right SCA, was between 22.5 and 75.0 mm, and for the left side, it's between 48.7 and 56.8 mm. CONCLUSIONS: The inferior thyroid artery is one of the arteries most susceptible to variations in terms of origin and size. With differences between the two sides (right and left), as well as differences related to gender.

Computed tomography-assessed variations of the carotid sinus.

PURPOSE AND BACKGROUND: Previous studies have identified variations regarding the morphology and location of the carotid sinus, a phenomenon still not commonly approached or studied on computed tomography angiography (CTA). Detailed characterization of the carotid sinus was performed on CTAs, determining its position, diameter and length. METHODS: The study group included 43 patients with disease-free carotid trunks subjected to cervical CTA. We measured the terminal caliber of the common carotid artery (CCA), as well as the calibers of the internal (ICA) and external carotid arteries (ECA) at their origin. The diameters were correlated with the location and the shape of the carotid sinus. We also measured the length of the sinus dilatation (carotid bulb), in regard to its location on the terminal branches of the common carotid artery. RESULTS: Mean diameters of the studied arteries were 7.39 ± 1.04 mm for the CCA, 6.71 ± 1.49 mm for the ICA and, respectively, 4.27 ± 0.75 mm for the ECA. The classical position of the carotid sinus was seen in 80% of cases, the rest being considered anatomical variants. The length of the carotid bulb on the ICA was 9.99 ± 2.22 mm, showing variability between genders. CONCLUSIONS: The carotid sinus does not always extend to the ICA, presenting different distribution patterns that might be relevant in sinus pathology from a clinical point of view, respectively from a surgical point of view during invasive or minimally invasive interventions on the carotid axis.

Axial and para-axial loading response evaluation on human cadaver-harvested lumbar vertebral blocks: In vitro experiment with possible clinical implications for clinical practice.

The aim of the present study conducted on the lumbar spine was to confirm that the pronounced decrease in resistance in the system is a phenomenon that can be eminently affected by the adaptive changes that occur at the level of the intervertebral disc at axial mechanical stresses. The biomechanical trial was carried out on 11 lumbar segments L1-L5, gathered from adult human cadavers. The dissection considered the complete keeping of all bone, disc, articulated and ligamentous components in their anatomical position. All 11 samples were frozen 24 h prior to the performance of the biomechanical measurement. The specimens were placed in the testing device, their placement being conditioned by the estimated dimensional values. Thus, to calculate the load and axial resistance, the models were placed vertically, central between the test machine ferries. The testing was carried out by applying variable forces and displacement supervision. The displacement interval was represented by a segment of 0-10 mm with surveillance every 2 mm. Mobility in the sagittal plane (flexion earlier in our case) was much higher than that in the frontal plane, obviously limiting mobility via the intervertebral disc and articular complex through the presence of arches. Statistical analysis demonstrated the lack of any correlation values between the two types of movements (R2=0.005507), underlining the absence of any prediction elements. A noteworthy aspect is that the correlations appeared low, statistically insignificant, even within the same movement in the sagittal plane between the two levels, L1-L3 and L3-L5 (R2=0.610427), which may lead to the possibility of the emergence of significant differences in mobility between respective levels. The behavior type of the monitored specimens and the results obtained allowed the mapping of objective parallelism between the values obtained and the behavior in vivo of the lumbar vertebral segment.

Morphometry of the Entire Internal Carotid Artery on CT Angiography.

Background and Objectives: Knowledge of the internal carotid artery's (ICA) morphometric features is influential in outlining surgical and minimally invasive procedures in the neurovascular field. Many studies have shown divisive numbers regarding the ICA's caliber, with the measuring point of the artery sometimes differing. This study presents ICA dimensions based on computed tomography angiography in each of its seven segments as per Bouthillier's classification, correlating vascular dimensions with anthropometric parameters. Materials and Methods: A thorough CT angiography analysis was performed on 70 patients with internal carotid vessels unaffected by atherosclerotic disease. The extracranial part of the ICA was measured in four locations-carotid bulb, post-bulbar dilation, at its cervical midpoint, and below its entrance into the carotid foramen. Single landmarks were used for measurements in the intracranial segments. ICA length was assessed in the neck region and also in the cranial cavity. Craniometric measurements were performed on sagittal and coronal CT reconstructions. Patient height was taken into consideration. Results: The largest ICA portion is near its origin in the carotid sinus area (7.59 ± 1.00 mm), with a steep decline in caliber following its extracranial course. Distal ICA presented values somewhat similar to its proximal intracranial segment diameters (4.67 ± 0.47 mm). Dimensions of the ICA in the intracranial segments start from a value of 4.53 ± 0.47 mm and decrease by approximately 40% when reaching the origin of the middle cerebral artery (2.71 ± 0.37 mm), showing a marked decrease in caliber after the emergence of the most critical collateral artery, the ophthalmic branch. The length of the ICA varies between genders, with the male ICA being about 10 mm longer in total length than female ICA; this difference is also correlated with patient height and skull dimensions. Conclusions: Both intra- and extracranial ICA have variable dimensions and length related to gender and anthropometric parameters, with no significant differences obtained concerning side or age.

Morphological assessments on the arteries of the superior renal segment.

The study was performed on 461 renal arteries in order to assess some morphological aspects regarding the arteries that supply the superior renal segment using as study methods: dissection, injection of contrast medium, injection of plastic followed by corrosion together with the examination of MRI and renal angiographies (simple and angio CT). The posterior arteries of the superior renal segment originate mostly from the posterior terminal branch of the renal artery as 1-3 arterial branches. In only 42 cases, we found posterior branches that do not participate in the supply of the superior renal pole. In 190 cases, the anterior arteries of the superior segment originated from the anterior division of the renal artery and in 73 cases directly from the trunk of the renal artery. 34 cases were assessed as a terminal division of the renal artery, while the origin from the posterior division of the renal artery was encountered in 18 cases. In 138 cases, the artery of the superior segment originated from a supplementary renal artery, double (118 cases) or triple (20 cases); in this situation, from the polar artery started the inferior suprarenal artery, except five cases where it originated from the aorta. Of the total of 461 samples, in 244 cases the renal approach was performed above the renal hilum, as proper superior polar arteries and in 217 cases the artery entered through the upper part of the hilum as an apical artery. The morphology of the arteries of the superior renal segment shows a significant degree of variability mostly in what concerns the anterior ones. Frequently we encountered a clear delimitation of the superior renal segment (in 61% of the cases), a situation that allows a relatively facile nephrectomy.