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Extracorporeal life support (ECLS) is an important tool in managing severe cardio-circulatory and respiratory failures. The axillary and the femoral sites are the most frequently used for arterial cannulation. There is no current evidence favoring one site over the other. We tested the hypothesis that the axillary and femoral arterial cannulation site may have different effects on left ventricular (LV) outflow. Seven patients with femoro-axillary ECLS and 4 patients with femoro-femoral ECLS were prospectively studied using the Pulse-wave Doppler (PWD) velocity time integral (VTI) in the descending thoracic aorta (DTA VTI) at different short-time variations of ECLS flow rates during the ECLS weaning process. The measurements were safe and feasible in all patients. We found a directly proportional correlation between DTA VTI and ECLS flow rate for femoro-axillary cannulation (P < 0.05) and an inversely proportional correlation in the case of femoro-femoral cannulation (P < 0.05). This is the first reported utilization of DTA VTI during ECLS that could improve our understanding of the LV-aorta interactions in patients with ECLS. DTA VTI could be used as a tool, guiding weaning from ECLS.

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The subscapular, anterior circumflex, and posterior circumflex arteries arise from the third part of the axillary artery. During dissection of the right upper limb of the cadaver of a 70-year-old male, a common trunk was observed arising from the third part of the axillary artery which, after traveling for 0.5 cm, bifurcated into subscapular and posterior circumflex humeral arteries. The common trunk was crossed anteriorly by the radial nerve. The medial nerve was formed by medial and lateral roots on the medial side of the third part of the axillary artery, remaining medial to the brachial artery up to the cubital fossa and then following its usual course thereafter. Awareness of the vascular variations observed in the present case is important when conducting surgical procedures in the axilla, for radiologists interpreting angiographs, and for anatomy-pathologists studying rare findings

As artérias subescapular, circunflexa anterior e circunflexa posterior se originam da terceira parte da artéria axilar. Durante a dissecção de membro superior direito de um cadáver humano com 70 anos de idade, do sexo masculino, um tronco comum foi observado originando-se da terceira parte da artéria axilar, após um percurso de 0,5 cm, bifurcando-se em artéria subescapular e artéria circunflexa posterior do húmero. O tronco comum era cruzado anteriormente pelo nervo radial. O nervo medial era formado por raízes medial e lateral, no lado medial da terceira parte da artéria axilar, permanecendo em posição medial à artéria braquial até a fossa cubital e seguindo seu curso usual a partir de então. Conhecimento das variações vasculares observadas neste caso é importante ao executar procedimentos cirúrgicos na axila, para radiologistas que interpretam radiografias, e também para anatomo-patologistas que estudam achados raros

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OBJECTIVES: Neuroprotection is of paramount interest in cardiac surgery. Right axillary artery cannulation is well established in aortic surgery because it significantly improves survival and outcome, but malperfusion of the right brain after direct cannulation has been reported. Anatomically, 4 vessel segments are potentially amenable for cannulation of the subclavian and axillary arteries. Clinical studies vary widely in dissection sites and cannulation techniques. We investigated critical flow dynamics in the right brain caused by arterial inflow after direct cannulation and specified cannulation positions that provide optimal cerebral perfusion. METHODS: Distances from the lateral margin of the axillary artery and the subclavian artery to the origin of the vertebral artery were measured in 14 human corpses by a flexible ruler. We calculated the hemodynamics within the vertebral artery, depending on different positions of the cannula tip, in a computer-calculated model. RESULTS: The mean distance from the axillary artery to the vertebral artery was 8.5 cm, and the mean distance from the subclavian artery to the vertebral artery was 6.7 cm. Computed flow calculations demonstrated reversed flow in the vertebral artery when the cannula tip was positioned too close to its orifice. To ensure safe supra-aortic flow, a cannula can be inserted securely up to 6.0 cm into the axillary artery and 4.2 cm into the subclavian artery. CONCLUSIONS: Direct cannulation of the right axillary artery can lead to cerebral malperfusion, caused by an obstruction of the vertebral artery's orifice by the arterial cannula or a subclavian steal phenomenon due to flow reversal. The safety of direct axillary artery cannulation can be improved by a well-considered dissecting site and insertion length of the cannula.

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Variations in the formation of the median nerve are of interest to anatomists, radiologists, and surgeons. These variations may be vulnerable to damage in surgical operations, but their knowledge also helps in the interpretation of a nervous compression having unexplained clinical symptoms. We studied the variation in the formation of the median nerve in 87 cadavers, i.e. 174 upper limbs of formalin preserved cadavers at the department of Anatomy, Subharti medical college. We observed an additional root taking part in the formation of the median nerve in 26.4% of upper limbs, unusual low formation of the median nerve in the arm in front of the brachial artery in 18.4% of upper limbs, and median nerve formation medial to the axillary artery in 10.3% of upper limbs. Knowledge of such anatomical variations is of interest to the anatomist and clinician alike. Surgeons who perform procedures involving neoplasm or trauma repair need to be aware of these variations.

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The superficial ulnar artery (SUA) is a rare anatomical variant that usually arises either in the axilla or the arm and runs a superficial course in the forearm, enters the hand, and participates in the formation of superficial palmar arch. During the routine dissection of cadavers in the department of anatomy, whilst preparing the specimen for medical students, an unusual bilateral branch of the axillary artery was found in one of the cadavers: a rare variant of the artery known as SUA, which originates from the 2nd part of the axillary arteries of both sides. The SUA is a known anatomical variant, but the bilateral high origin from the 2nd part of the axillary artery is extremely unusual. Its occurrence is of great clinical importance to the surgical and radiological departments.

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Axillary artery is one of the most important arteries of the upper limb, which is a continua- tion of the subclavian artery. It begins at the lateral border of the first rib and ends at the inferior border of the teres major where it becomes the brachial artery. Axillary artery has six important branches included: 1) Superior thoracic artery 2) Thoracoacromial artery 3) Lateral thoracic artery 4) Subscapular artery 5) Posterior circumflex humeral artery 6) Anterior circumflex humeral artery. Subscapular artery arises from the third part of axillary artery normally and then divides into cir- cumflex scapular artery that extremely enters the triangular space. The other branch of subscapular artery, the thoracodorsal artery, accompanies thracodorsal nerve to lateral border of scapula and supplies and innervates that region. In this case the subscapular artery was absent in both sides and instead of that the circumflex scapular artery was directly derived from axillary artery and the thoracodorsal artery is separated from circumflex scapular artery as a thin and short branch, too. It seemed that the lateral thoracic artery, which was thicker than its normal condition, supplied the muscles of the lateral part of scapula and the thoracodorsal muscle. Other branches of the axillary artery demonstrated without any abnormally. Since axillary artery has the highest rate of rapture and damage coming after the popliteal artery, knowing the variations is important and essential for surgeons, radiologist and anatomist.

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Maximal strength training with a focus on maximal mobilization of force in the concentric phase improves endurance performance that employs a large muscle mass. However, this has not been studied during work with a small muscle mass, which does not challenge convective oxygen supply. We therefore randomized 23 adult females with no arm-training history to either one-arm maximal strength training or a control group. The training group performed five sets of five repetitions of dynamic arm curls against a near-maximal load, 3 days a week for 8 weeks. This training increased maximal strength by 75% and improved rate of force development during both strength and endurance exercise, suggesting that each arm curl became more efficient. This coincided with a 17-18% reduction in oxygen cost at standardized submaximal workloads (work economy), and a 21% higher peak oxygen uptake and 30% higher peak load during maximal arm endurance exercise. Blood flow assessed by Doppler ultrasound in the axillary artery supplying the working biceps brachii and brachialis muscles could not explain the training-induced adaptations. These data suggest that maximal strength training improved work economy and endurance performance in the skeletal muscle, and that these effects are independent of convective oxygen supply.

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BACKGROUND AND AIM OF THE STUDY: Unexpected sustained underestimation of the central aortic pressure by the radial arterial pressure commonly develops following cardiopulmonary bypass (CPB) in valvular heart surgery (VHS), leading to an inappropriate use of vasopressors. The study aim was to identify clinical predictors leading to a sustained inappropriate difference between the radial and femoral arterial pressure (IDRF) in VHS. METHODS: A total of 200 patients undergoing VHS was studied prospectively. Those patients who developed sustained IDRF (systolic IDRF > or =10 mmHg and/or mean IDRF > or =5 mmHg) from immediately after discontinuation of CPB until the end of the surgery were compared with patients who did not develop any IDRF. RESULTS: Data from seven patients who required second aortic cross-clamping and re-CPB were excluded from the analysis; thus, data from 193 patients were analyzed. In total, 53 patients (27.5%) developed sustained IDRF, whereas 80 patients (41.4%) did not develop any IDRF. In multivariate analysis, female gender, the presence of atrial fibrillation and diuretic use were identified as independent preoperative predictors; longer-duration aortic cross-clamping and use of larger amounts of vasopressin during CPB were identified as independent operative risk factors of the sustained IDRF. CONCLUSION: When an erroneously low radial arterial pressure is suspected following CPB in this subset of patients undergoing VHS, monitoring of the femoral or axillary arterial pressure should be considered to guide hemodynamic management, as there is an increased risk of persistence of this phenomenon.

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OBJECTIVES: The aim of this study was to determine changes in axillary artery diameter and peak systolic velocity in asymptomatic individuals during upper limb positioning commonly used to assess vascular pathology in athletes. DESIGN: Repeated measures observational study. SETTING: Physiology laboratory. PARTICIPANTS: Subjective and objective screening excluded individuals with past, or present, conditions related to neurovascular compression syndromes. Thirty-one subjects (21 females, 10 males; mean age: 25+/-4 years) were included in the final analysis. MAIN OUTCOME MEASURES: Sonographically determined axillary artery diameter and peak systolic velocity, as well as symptom production, were recorded for a series of 12 randomised arm positions, incorporating varying degrees of abduction, external rotation, and horizontal flexion/extension. RESULTS: The majority of arm positions revealed no change in artery diameter and peak systolic velocity. However, at the extreme of abduction, and arm positions incorporating 120 degrees abduction, significant (p<0.0005) reductions in axillary artery diameter were noted. All mean results masked wide heterogeneity: 13% demonstrating a greater than 50% reduction in diameter, 10%, a doubling of peak systolic velocity, and 42%, reporting symptoms. CONCLUSIONS: The number of individual clinically "positive" responses questions the specificity of individual diagnostic tests, such as the hyperabduction manoeuvre, and highlights the need to interpret test results in conjunction with the subjective assessment and other physical findings from the objective assessment.

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Axillary artery perfusion is an attractive alternative to reduce the frequency of atheroembolism in extensive atherosclerotic aorta and aortic aneurysms. This study was conducted to evaluate the flow dynamics of axillary artery perfusion. Transparent glass models of a normal aortic arch and an aortic arch aneurysm were used to evaluate hydrodynamic properties. Streamline analysis and distribution of the shear stress was evaluated using a particle image velocity method. In the normal aortic arch model, rapid flow of 80 cm/s from the right axillary artery ran out from the brachiocephalic artery and grazed the lesser curvature of the aortic arch. There was secondary reversed flow in the ascending aorta. Flow from left axillary perfusion went straight to the descending aorta. In the aortic arch aneurysm model, flow from both axillary arteries hit the lesser curvature of the aortic arch and went into the ascending aorta with vortical flow. Distribution of shear stress was high along the jet from the ostium of the brachiocephalic artery and left subclavian artery. Flow in the aortic arch and the ascending aorta was unexpectedly rapid. Special care must be taken when the patient has frail atheroma around arch vessels or the lesser curvature of the aortic arch during axillary artery perfusion.

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The motive for this research was the use of the muscles of the scapular region in transposition, transplantation and reparative surgery and the need for more detailed knowledge of the blood supply to these muscles. In addition, the subscapular arterial tree may be used as a source of microvascular grafts to replace damaged or diseased portions of arteries, particularly in the hand and forearm. The research was conducted on 60 sides of corpses of adults of both sexes. It was noticed that the subscapular artery was present in 96.7% of cases and originated laterally to the pectoralis minor muscle in 76.7% of cases. The average calibre was 5.0 mm, and in 73.2% of cases it measured between 4.0 and 5.9 mm. The average length was 18.0 mm, ranging from 10.0 to 29.9 mm (76.7%). It presented in its course important relations with the axillary nerve (69%) and with the radial nerve (82.8%). Its branches were collateral (subscapular muscle - 61.3%) and terminal (except for the circumflex scapular artery), leading to the following muscles: serratus anterior (43.9%), latissimus dorsi (27.6%), and subscapular (23.3%). The thoracodorsal artery, one of the terminal branches, most frequently showed a calibre of between 2.0 and 3.9 mm (70.3%), collateral branches in 85.0%, was mainly distributed to the subscapular muscle (36.7%) and to the serratus anterior muscle (29.0%) and had terminal branches to the following muscles: latissimus dorsi (44.1%), serratus anterior (40.5%) and the subscapular (12.5%). The serratus anterior muscle received one branch in 39.5% and two branches in 41.9%, while the latissimus dorsi muscle received one branch in 66.7% and two branches in 23.1%.

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The goal of this research was to study some particular hemodynamic parameters and the endothelium-dependent vasodilation condition in patients with inherent forms of platelet dysfunction. The discovered changes in some particular hemodynamic blood stream characteristics increase the existing qualitative defect of platelets and have prohemorrhagic directivity.

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We investigated the quantitative contribution of all local conduit arterial, blood, and distal load properties to the pressure transfer function from brachial artery to aorta. The model was based on anatomical data, Young's modulus, wall viscosity, blood viscosity, and blood density. A three-element windkessel represented the distal arterial tree. Sensitivity analysis was performed in terms of frequency and magnitude of the peak of the transfer function and in terms of systolic, diastolic, and pulse pressure in the aorta. The root mean square error (RMSE) described the accuracy in wave-shape prediction. The percent change of these variables for a 25% alteration of each of the model parameters was calculated. Vessel length and diameter are found to be the most important parameters determining pressure transfer. Systolic and diastolic pressure changed <3% and RMSE <1.8 mmHg for a 25% change in vessel length and diameter. To investigate how arterial tapering influences the pressure transfer, a single uniform lossless tube was modeled. This simplification introduced only small errors in systolic and diastolic pressures (1% and 0%, respectively), and wave shape was less well described (RMSE, approximately 2.1 mmHg). Local (arm) vasodilation affects the transfer function little, because it has limited effect on the reflection coefficient. Since vessel length and diameter translate into travel time, this parameter can describe the transfer accurately. We suggest that with a, preferably, noninvasively measured travel time, an accurate individualized description of pressure transfer can be obtained.

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BACKGROUND: The goal of the study was to compare stroke volume (SV) and respiratory stroke volume variation (SVV) measured by pulse-contour analysis and aortic Doppler. METHODS: These were measured by pulse-contour analysis and thermodilution (PiCCO) and by aortic pulsed wave Doppler with transoesophageal echocardiography in patients undergoing abdominal aortic surgery. Simultaneous measurements were done at different times of surgery. All data were recorded on PiCCOwin software and videotape and analysed off-line by a blinded investigator. RESULTS: A total of 114 measurements were achieved in 20 patients. There was a good correlation and small bias between the PiCCO and the echo-Doppler values of the mean SV [r=0.885; bias=0.2 (8) ml], and between the minimum [r=0.842; bias=1 (9) ml] and maximum SV [r=0.840; bias=2 (10) ml] values. CONCLUSIONS: There is a fair correlation between pulse-contour analysis and aortic Doppler for beat-by-beat measurement of SV but not for calculation of SV respiratory ventilation.

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BACKGROUND: Flushing of radial arterial catheters may be associated with retrograde embolization of air or thrombus into the cerebral circulation. For embolization into the central circulation to occur, sufficient pressure must be generated during the flushing process to reverse antegrade blood flow in the arterial blood vessels of the upper extremity. This ultrasound study was designed to examine whether routine radial catheter flushing practices produce retrograde blood flow patterns in the brachial and proximal axillary arteries. METHODS: Duplex ultrasound examinations of the brachial and axillary arteries were conducted in 100 surgical patients to quantify direction and velocity of blood flow during catheter flushing. After obtaining Doppler spectral images of brachial and axillary arterial flow patterns, manual flushing was performed by injecting 10 ml flush solution using a syringe at a rate reflecting standard clinical practices. The flow-regulating device on the pressurized (300 mmHg) arterial flushing-sampling system was then opened for 10 s to deliver a rapid bolus of fluid (flush valve opening). RESULTS: The rate of manual flush solution injection through the radial arterial catheter was related to the probability of retrograde flow in the axillary artery (P < 0.001). Reversed arterial flow was noted in the majority of subjects (33 of 51) at a manual flush rate of less than 9 s and in no subjects (0 of 48) at a rate 9 s or greater. Retrograde flow was observed less frequently during flush valve opening (2 of 99 patients; P < 0.001 vs. manual flushing). CONCLUSIONS: Rapid manual flushing of radial arterial catheters at rates faster than 1 ml/s produces retrograde flow in the proximal axillary artery.

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BACKGROUND: The aim of our anatomic study was to assess whether the commonly used method of perfusion through the right axillary artery is sufficient in providing uniform distribution of blood to both hemispheres of the brain in patients undergoing surgery of the aortic arch. We considered that critical arteries to examine are anterior and left posterior communicating arteries of the circle of Willis because the absence or insufficiency of either one would drastically endanger perfusion to the left hemisphere of the brain. The existence and the diameters of these arteries were studied. METHODS: The material was collected as a part of normal forensic medicine autopsies. The anatomy of the cerebral arteries of 87 deceased individuals was assessed by angiography and permanent silicone casts. A new classification was created for this study. According to a recent observation in the literature we defined the minimum threshold of arterial diameter that allows cross flow to be 0.5 mm. We also repeated analyses using 1 mm as a threshold, which has also been recommended. RESULTS: In our material 22% of the anterior communicating arteries and 46% of the left posterior communicating arteries were missing. In this anatomic population the perfusion to the left hemisphere might have been insufficient in 14% of the patients at a threshold of 0.5 mm and in 17% at a threshold of 1 mm. CONCLUSIONS: When the right axillary artery is used for perfusion, the circulation to the contralateral hemisphere seems to be good for most patients undergoing operations of the aortic arch, but additional means of brain protection are still needed.

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BACKGROUND AND OBJECTIVE: Inaccurate measurements of body temperature following cardiopulmonary bypass may be associated with serious complications. The purpose of this study was to determine whether axillary and tympanic temperature measurements correlate with the urinary bladder temperature in the early postcardiac surgery period. METHODS: Forty-nine adult patients who underwent cardiac surgery under cardiopulmonary bypass at our institution were prospectively studied. Urinary bladder, right axillary, right tympanic and left tympanic temperature measurements were simultaneously recorded at 0, 6, 12 and 18 h following cardiopulmonary bypass. Patients had one to four sets of recordings and a total of 629 temperature measurements were recorded. The mean difference (bias) between the bladder and each of the other methods and limits of agreement were calculated using Bland and Altman method. RESULTS: The mean core body temperature recorded from the bladder on admission to the intensive care unit was 36.4 degrees C. After 6, 12 and 18 h the mean core body temperature was 37.4 degrees C (range: 35.2-39.0), 37.5 degrees C and 37.45 degrees C, respectively. The mean differences (bias) between the bladder temperature and the other three methods were: left tympanic, 0.65 degrees C (95% CI: -0.24 to 1.58); right tympanic, 0.57 degrees C (95% CI: -0.48 to 1.63) and right axillary, 0.55 degrees C (95% CI: -0.27 to 1.36). CONCLUSIONS: The axilla and tympanic membrane are unreliable sites for core body temperature measurement early after cardiopulmonary bypass in adult patients and clinical decisions should be based on more reliable methods.

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BACKGROUND: This study was undertaken to identify preoperative and postoperative predictors of hospital death of patients with acute type A aortic dissection. METHODS: Between May 1,1992, and July 31, 2004, 106 consecutive patients (59 male and 47 female, mean age 62.2 +/- 12.1 years) with acute type A aortic dissection underwent surgery with open technique and cerebral protection by antegrade selective cerebral perfusion. The external iliac artery or femoral artery alone was used for arterial cannulation in 37 patients; however, the right axillary artery was cannulated in 69 patients. Univariate analysis of potential risk factors was performed to identify risk factors for hospital death and was followed by multivariate analysis by a stepwise logistic regression model to identify independent risk factors. RESULTS: Sixteen patients died postoperatively, and the overall hospital mortality rate was 15.1%. Univariate analysis revealed shock (p = 0.020), visceral ischemia (p = 0.007), root replacement (p = 0.041), and absence of axillary artery perfusion (p = 0.003) as significant risk factors for hospital death. Multivariate analysis revealed visceral ischemia (p = 0.0028, odds ratio 18.4) and absence of axillary artery perfusion (p = 0.0014, odds ratio 8.2) as independent preoperative and intraoperative predictors of hospital death. CONCLUSIONS: Achievement of greater success in the surgical treatment of acute type A dissection will require axillary artery cannulation and measures to prevent visceral malperfusion.

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BACKGROUND AND OBJECTIVES: Short reports have noted that percutaneous prelocation is helpful in determining the anatomic course of a peripheral nerve, and, thereby, may serve as a guide for block needle insertion. We prospectively studied percutaneous electrode guidance to assist axillary brachial plexus blocks. METHODS: In 131 consecutive patients, the tip of an insulated needle emitting 5 mA was placed on the skin above and below the axillary artery to obtain a hand motor response characteristic of the median, ulnar, and radial nerves in succession. The current was reduced until all movement had ceased. The needle was then inserted toward the nerve to be blocked, decreasing the intensity from 2 mA to 0.5 mA, so that the same selected motor response was still obtained. The length of the needle inserted was noted, and 1.5% lidocaine was injected. Pain verbal analogic score (VAS) values were noted during both procedures. Complete sensory blockade was evaluated at 30 min. RESULTS: Rates of successful percutaneous electrode guidance were 94.6% for the median nerve, 89.4% for the radial nerve, 88.5% for the ulnar nerve, and 85.5% for all 3 nerves together. A significant correlation was found between the lowest percutaneous current applied and the depth of the nerve stimulated at 0.5 mA. Pain VAS values were significantly lower during percutaneous stimulation than during needle insertion (P <.05). Sensory block for all 3 nerves was noted in 92% of patients. CONCLUSIONS: Percutaneous electrode guidance using the insulated needle enabled clinicians to locate the terminal branches of the plexus in the axilla and appreciate their depth. This method could, therefore, minimize patient discomfort and perhaps the risk of nerve trauma.

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STUDY DESIGN: Prospective comparative study. OBJECTIVE: To establish the use of Color Doppler Ultrasonography to investigate internal mammary artery. SUMMARY OF BACKGROUND DATA: Breast asymmetry in female adolescents with right convex idiopathic scoliosis was supposed to be linked with anatomic and functional asymmetry of the internal mammary artery that is the main supplier to the mammary gland. However, no measurements of anatomic and hemodynamic parameters of internal mammary artery have been made to justify or to reject the hypothesis of asymmetric blood flow volume to the breasts and costosternal junction in female adolescent scoliotics. Color Doppler Ultrasonography is a well established noninvasive method to assess vessel anatomy and hemodynamics. METHODS: Twenty female adolescents with right thoracic scoliosis and 16 comparable female individuals without spine deformity were examined with Color Doppler Ultrasonography to measure at the origin of internal mammary artery lumen diameter, cross sectional area, time average mean flow and flow volume per minute and were compared each other. RESULTS: The reliability of Color Doppler Ultrasonography was high and the intraobserver variability low (ANOVA, P = 0.92-0.94). There was no statistically significant difference in the ultrasonographic parameters of the internal mammary artery between right and left side in each individual as well as between scoliotics and controls. CONCLUSIONS: Color Doppler Ultrasonography applied to assess anatomic or hemodynamic blood flow parameters at the origin of internal mammary artery was proven a highly reliable method. Color Doppler Ultrasonography disclosed no side-differences, while there were no differences between scoliotics and controls. Thus, it seems that this study cannot justify previous theories for development of right thoracic scoliosis in female adolescents.

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