Arterial Pattern Research Articles

The mouse allantois: new insights at the embryonic-extraembryonic interface.

During the early development of Placentalia, a distinctive projection emerges at the posterior embryonic-extraembryonic interface of the conceptus; its fingerlike shape presages maturation into the placental umbilical cord, whose major role is to shuttle fetal blood to and from the chorion for exchange with the mother during pregnancy. Until recently, the biology of the cord's vital vascular anlage, called the body stalk/allantois in humans and simply the allantois in rodents, has been largely unknown. Here, new insights into the development of the mouse allantois are featured, from its origin and mechanism of arterial patterning through its union with the chorion. Key to generating the allantois and its critical functions are the primitive streak and visceral endoderm, which together are sufficient to create the entire fetal-placental connection. Their newly discovered roles at the embryonic-extraembryonic interface challenge conventional wisdom, including the physical limits of the primitive streak, its function as sole purveyor of mesoderm in the mouse, potency of visceral endoderm, and the putative role of the allantois in the germ line. With this working model of allantois development, understanding a plethora of hitherto poorly understood orphan diseases in humans is now within reach. This article is part of the theme issue 'Extraembryonic tissues: exploring concepts, definitions and functions across the animal kingdom'.

Vascular Safe Zones for Facial Soft Tissue Filler Injections.

The number of soft tissue filler injections performed by aesthetic injectors has continued to increase over the last few years. To provide a high standard of safety and achieve individualized, reproducible, and long-lasting outcomes, aesthetic injectors must have a solid foundation in anatomy, facial biomechanics, rheology, and injection biomechanics. Adverse events associated with soft tissue filler injections can be severe, especially if the aesthetic injector unintentionally injects the soft tissue filler into the patient's arterial vascular circulation and the administered product reaches the arterial bloodstream. Although the face has a rich arterial vascular supply that may seem overwhelmingly complex, it can be broken down systematically according to its internal and external vascular territories. To provide guidance for aesthetic practitioners performing minimally invasive facial injections for aesthetic purposes, this narrative article will discuss the course, depth, and branching pattern of the facial arteries based on the most frequently injected anatomical regions. In this article, we focus on vascular safe zones rather than danger zones .

Techniques and pitfalls of coronary arterial reimplantation in anatomical correction of transposition.

We assessed the anatomical variations in coronary arterial patterns relative to the techniques of reimplantation in the setting of the arterial switch operation, relating the variations to influences on outcomes. We reviewed pertinent published investigations, assessing events reported following varied surgical techniques for reimplantation of the coronary arteries in the setting of the arterial switch procedure. The prevalence of reported adverse events, subsequent to reimplantation, varied from 2% to 11%, with a bimodal presentation of high early and low late incidence. The intramural pattern continues to contribute to mortality, with some reports of 28% fatality. The presence of abnormal course relative to the arterial pedicles in the setting of single sinus origin was associated with a three-fold increase in mortality. Abnormal looping with bisinusal origin of arteries was not associated with increased risk. The techniques of transfer of the coronary arteries can be individually adapted to cater for the anatomical variations. Cardiac surgeons, therefore, need to be familiar with the myriad creative options available to achieve successful repair when there is challenging anatomy. Long-term follow-up will be required to affirm the superiority of any specific individual technique. Detailed multiplanar computed-tomographic scanning can now reveal all the variants, and elucidate the mechanisms of late complications. Coronary angioplasty or surgical revascularization may be considered in selected cases subsequent to the switch procedure.

Use of duplex echoencephalography to evaluate brain death in children: A novel approach to the diagnosis.

Brain death is defined as the irreversible cessation of brain function with a known etiology. This study aims to establish the value of duplex echoencephalography (DEG) in children fulfilling clinical brain death diagnostic criteria. DEG must show intracranial brain structures. Power Doppler is used to assess venous flow when feasible. Color Doppler patterns in all major arteries are assessed. Spectral analysis of arterial flow is divided into four grades: grade 1: inverted flow during entire diastole with time average peak velocity (TAPV) less or equal to zero; grade 2: disappearance of the inverted diastolic flow at the end of diastole; grade 3: oscillating pattern in early diastole; and grade 4: no diastolic flow with systolic blip. To fulfill diagnosis of brain death, brain perfusion must be lost for 30 minutes. DEG is performed in 41 pediatric patients. In infants, loss of venous flow occurs regardless of the etiology. Grade 1 is the most common arterial color flow pattern and TAPV is always below zero. A pulsatile color flow is associated with three other types of flow patterns (grades 2-4). TAPV is not calculated, when there is loss of diastolic flow. Diagnosis of brain death is validated using nuclear brain scan in 4patients. Two have a grade 1 flow pattern, while the other two have a grade 4 flow pattern. In children, DEG following a strict protocol can be used to confirm diagnosis of brain death in the appropriate clinical setting.

Anatomy of the coronary arteries in Eurasian wild boar (Sus scrofa)

Abstract Coronary circulation determines the proper functioning of the heart muscle and blood circulation in the body. Cardiovascular diseases in humans are creating an ever-increasing demand for more research into their pathogenesis, diagnosis and treatment. Animal models of organs are an indispensable part of research for the development of human medicine. Due to the high genetic similarity, the most commonly used donor is the domestic pig. The Eurasian wild boar is the ancestor of the domestic pig and an invasive species not covered by European protection programmes. Given its analogous structure and genotype to the pig, it could potentially also become an organ donor. The aim of this study was to analyse the normal coronary anatomy of the Eurasian wild boar and compare it to humans, domestic pigs and other animal species. The study was conducted on 60 wild boar hearts. Twenty-eight slides were prepared using acrylic, while liquid latex was injected into 32 hearts. The blood vessels were then manually prepared using surgical instruments for examination. Both the right coronary artery and the left coronary artery of the boar diverge from the ascending aorta from opposite aortic sinuses. The left coronary artery begins its course in the left aortic sinus, starting between the left appendage and the pulmonary trunk. It then heads inferiorly. The right coronary artery supplies blood to the right atrium and right ventricle. The study points to the wild boar coronary system’s individual morphological features and notes the common arterial patterns in mammals.

A rare bifurcation of the external iliac artery into femoral and deep femoral arteries

The current cadaveric report describes a quite rare unilateral bifurcation of the external iliac artery (EIA) into two femoral arteries (FAs) of almost equal diameter and parallel course, at the level of the inguinal ligament (IL). The variant FAs were identified on a 75-year-old formalin-embalmed female cadaver, derived from a body donation program after a signed informed consent. The EIA bifurcated into a FA and a deep femoral artery (DFA). The DFA extremely high origin was identified at the IL level. Both lateral and medial circumflex femoral arteries originated from the DFA. The in-depth knowledge of the FA variant origin is of paramount importance to vascular surgeons and interventional radiologists during vessel catheterization and attempts to interpret the angiographic findings. In particular, the DFA's high origin from the EIA and the coexistence of two FAs in a parallel course may pose problems to clinicians during angiographic procedures leading to diagnostic errors. The DFA high origin may also complicate femoral arterial and venous puncture and femoral nerve blocks, due to the close neurovascular relationship. There is a possibility for the FA to be mistaken for a vein leading to accidental intra-arterial injection and consequently thrombosis. Thus, variable arterial pattern is important to be identified preoperatively using Doppler ultrasound imaging.

CT Angiographic Study on the Variations of the Hepatic Arteries in the Living Liver Donors of the South Indian Population.

Living liver donor transplantation is the last option for the end stage liver diseases. The variations in the hepatic artery of the liver donor may lead to poor outcome, or may end with major post-operative complications such as hepatic artery thrombosis. To prevent the post-operative complications and to increase the success rate of the liver transplant surgeries, CT evaluation of the hepatic arteries is essential. Thus, the present study was aimed to study the variations of the hepatic arteries in the living liver donors. A total of 200 CT angiograms were collected from the department of Radiology from August 2018 to December 2021, and the evaluation was carried out in the Department of Anatomy, Deccan College of Medical Sciences, Hyderabad. All the CT angiograms were studied for the variations of hepatic arterial system, and the observed variations were noted and the incidence was calculated. The normal anatomy was observed in 62.5% liver donors and 37.55% of liver donors showed variations in hepatic arterial pattern. The incidence of the replaced left hepatic retry, replaced right artery, replaced left along with replaced right hepatic artery was observed as 11.5%, 9.5% and 3% respectively. The incidence of left and right accessory hepatic arteries was 7% and 4% respectively and the replaced right hepatic artery with accessory left hepatic artery was observed in 1.5% cases. The variations observed in the hepatic arterial pattern observed in this study could be helpful to the surgeons, while planning and selecting the suitable liver donors and also may minimise the risk and increase the success rate.Â

Lower Nose Arterial Plexus and Implications for Safe Filler Injections.

The lower nose has abundant blood supply; however, nasal tip necrosis still occurs following filler injections. This study revealed the complicated pattern of the arterial supply of the lower nose. The arterial pattern of the lower nose was studied in 40 cadavers using conventional dissections and translucent modified Sihler staining. Two arterial rings were connected in a figure of eight. The upper ring (nasal arterial circle) consisted of the lateral nasal and the subalar arteries encircling the nasal tip and alae. The lower ring (arterial plexus of the upper lip) was more important because of the contribution of the facial and superior labial arteries. This specific feature had not been mentioned elsewhere. Understanding this specific feature of the blood supply of the lower nose is essential for aesthetic physicians to perform the appropriate techniques during filler injection procedures in the nasal and perioral regions.

Unconventional Obturator Artery Nutrient Branch: Image of an Anatomical Variation.

Variations in vascular anatomy are of great concern to surgeons, as proper identification of aberrant arteries can reduce the risk of iatrogenic injury and improve patient outcomes. Several studies have highlighted the irregular branching pattern of pelvic arteries, with a recent focus on the obturator artery (OA). The OA has an inconstant origin from the internal iliac artery, external iliac artery, or inferior epigastric artery. Within the pelvis, the OA can give off muscular branches and nutrient vessels to the ilium and pubis. Though occasionally described in text, few resources employ images of human donors that depict branches arising from the OAs. Out of the 34 hemisected pelves studied, we identified 1 individual with a substantial nutrient vessel branching unilaterally from the OA. Herein, we present the first image of this unconventional nutrient artery. This vessel should be highlighted given that its size and course make it particularly vulnerable during intrapelvic surgeries such as pelvic lymph node dissection or in procedures requiring arterial embolization of the OA.

Role of preoperative prediction of microvascular invasion in hepatocellular carcinoma based on the texture of FDG PET image: A comparison of quantitative metabolic parameters and MRI.

Objective: To investigate the role of prediction microvascular invasion (mVI) in hepatocellular carcinoma (HCC) by 18F-FDG PET image texture analysis and hybrid criteria combining PET/CT and multi-parameter MRI. Materials and methods: Ninety-seven patients with HCC who received the examinations of MRI and 18F-FDG PET/CT were retrospectively included in this study and were randomized into training and testing cohorts. The lesion image texture features of 18F-FDG PET were extracted using MaZda software. The optimal predictive texture features of mVI were selected, and the classification procedure was conducted. The predictive performance of mVI by radiomics classier in training and testing cohorts was respectively recorded. Next, the hybrid model was developed by integrating the 18F-FDG PET image texture, metabolic parameters, and MRI parameters to predict mVI through logistic regression. Furthermore, the diagnostic performance of each time was recorded. Results: The 18F-FDG PET image radiomics classier showed good predicted performance in both training and testing cohorts to discriminate HCC with/without mVI, with an AUC of 0.917 (95% CI: 0.824–0.970) and 0.771 (95% CI: 0.578, 0.905). The hybrid model, which combines radiomics classier, SUVmax, ADC, hypovascular arterial phase enhancement pattern on contrast-enhanced MRI, and non-smooth tumor margin, also yielded better predictive performance with an AUC of 0.996 (95% CI: 0.939, 1.000) and 0.953 (95% CI: 0.883, 1.000). The differences in AUCs between radiomics classier and hybrid classier were significant in both training and testing cohorts (DeLong test, both p < 0.05). Conclusion: The radiomics classier based on 18F-FDG PET image texture and the hybrid classier incorporating 18F-FDG PET/CT and MRI yielded good predictive performance, which might provide a precise prediction of HCC mVI preoperatively.

The acute effect of maximal exercise on arterial stiffness in adults with and without intellectual and developmental disabilities.

We compared central and peripheral arterial stiffness response patterns between persons with and without intellectual and developmental disabilities (IDD) of different age groups at rest and following a cardiopulmonary exercise test (CPET). Fifteen young adults with and without IDD, and 15 middle-aged adults without IDD performed a CPET. Central and peripheral arterial stiffness were measured at rest and following CPET using estimates of carotid-femoral (cfPWV), carotid-radial (crPWV), and carotid-ankle (cdPWV) pulse wave velocity derived from piezoelectric mechano-transducers. cfPWV remained unchanged following CPET in adults with and without IDD but increased in middle-aged adults (d=0.85; 95% CI: 0.27-1.42m·s-1, p=0.005), whereas cdPWV was similarly reduced (d= -0.77; 95% CI: -1.06 to -0.48m·s-1, p<0.001) in all groups. crPWV remained unchanged in all groups. These results were independent of exercise-related changes in mean arterial pressure. Overall group differences suggested that persons with IDD (d = -1.78; 95% CI: -3.20 to -0.37m·s-1, p=0.009) and without IDD (d = -1.84; 95% CI: -3.26 to -0.43m·s-1, p=0.007) had lower cfPWV than middle-aged adults. We found no evidence of early vascular aging and diminished vascular reserve following CPET in adults with IDD.

Study of Arterial Blood Gas Analysis in Moderate-to-Severe COVID-19 Patients.

BackgroundThe high prevalence of pneumonia and renal involvement in coronavirus disease 2019 (COVID-19) leads to frequent acid-base abnormalities in serious patients and affects prognosis. In this study, we aimed to assess the arterial blood gas (ABG) and acid-base patterns in COVID-19 patients admitted to a tertiary care hospital.MethodologyA retrospective observational study was conducted in a designated COVID-19 hospital involving 267 reverse transcription-polymerasechain reaction-positive COVID-19 patients. Demographic and laboratory data including ABG data within the first day after admission and in patients with multiple ABG analyses, only the first measurement was collected and analyzed statistically, including its association with comorbidities.ResultsThe most common age group of the patients was 51-60 years (30.8%), with a male predominance (male:female = 2.7:1). The most common comorbidities were hypertension, diabetes mellitus, and chronic obstructive pulmonary disease found in 147 (55%) COVID-19 patients. Alkalosis and acidosis were observed in 145 (54.3%) and 50 (18.7%) patients, respectively. The most common ABG abnormality observed was primary respiratory alkalosis with secondary metabolic acidosis in 67 (25.1%) patients, followed by primary respiratory alkalosis with secondary metabolic alkalosis in 54 (20.2%) patients. Statistically significant negative correlation was found with PaCO2 and pH (r = -0.530, p < 0.0001), statistically significant positive correlation was found between pH and base (r = 0.533, p < 0.0001), pH and TCO2 (r = 0.260, p < 0.0001), and pH and HCO3 (r = 0.354, p < 0.0001).ConclusionsAcid-base abnormalities are commonly encountered in COVID-19 patients. Respiratory alkalosis as a part of a single or mixed pattern on ABG was the most common pattern found in critically ill COVID-19 patients. ABG on admission in moderate-to-severe COVID-19 patients can help in the early correction of metabolic abnormalities leading to improved patient outcomes.

Study on arterial patterns of human heart and their variations by using post-mortem coronary arteriogram in Tirupathi population

Background: The impact of post-mortem angiography increases because of the rapid evaluation of organ-specific vascular patterns, vascular alteration under pathologic and physiologic conditions and tissue changes induced by artificial and unnatural causes. Aim: To study the human heart arterial patterns and their variation by using post-mortem arteriogram. Materials and Methods: Eighty human fresh heart specimens were obtained from the Forensic Department, S.V. Medical College, Tirupati. The hearts were perfused with normal saline followed by injection of barium sulphate suspension and ligated at the proximal end of coronary arteries. Skiagrams were taken in different views and studied. Results: we have observed all the branches of right and left coronary arteries. The right and left dominance pattern, Vieussens annulus, anastomosis between the great blood vessels and posterior interventricular branches, AV nodal, SA nodal branches and variations of branches were noted in our study Conclusion: Our study will be useful in analyzing the arterial system of the heart and gives valuable supplement to conventional autopsy procedures.

Median Arcuate Ligament Syndrome with Common Hepatic and Splenic Arteries Directly Originating from the Abdominal Aorta: A Case Report

Introduction: Knowledge of the unpaired abdominal vasculature is important for uncomplicated operations. The absent celiac trunk has previously been reported; however, developmental alterations can result in a variety of branching patterns of the downstream arteries from the abdominal aorta. Case Presentation: A 53-year-old female patient with lymphoma underwent abdominopelvic computed tomography (CT) for staging. She had a history of postprandial off-and-on abdominal pain since her youth. CT scan revealed an absent celiac trunk with common hepatic and splenic arteries directly originating from the abdominal aorta. Compression of the median arcuate ligament had narrowed and angulated the 2 branches. Conclusions: When the celiac trunk is absent, its main branches may separately arise from the abdominal aorta. Also, due to the displacement of these branches, their path and diameter can vary from the normal.

An Unusual Presentation of Congenital Megacolon with A Rare Vascular Anomaly: A Case Report

Congenital megacolon also referred to as Hirschsprung’s disease or aganglionic megacolon is characterized by the absence of nerve plexus in the colon, it rarely affects the small intestine. Whereas acquired megacolon is a constant dilatation of the large intestine in the absence of disease but occurs due to various factors such as infections, emotional disturbances, stress, or secondary to inflammatory bowel diseases (IBD) such as ulcerative colitis, Crohn’s disease, and proctocolitis. In the present case, we report here an unusual form of megacolon. The sigmoid colon was significantly enlarged but twisting or volvulus was not detected. The ascending, transverse, and remaining part of descending colon and mesentery appeared normal, The possibility of false rotation of the gut was excluded. Interestingly, the artery supplying the left one-third of the transverse colon and descending colon originated from a branch of the middle colic artery. This anomalous artery was found to form a communication with the trunk of the inferior mesenteric artery, the Arc of Riolan, and gave branches that supplied the descending colon. The left colic artery was absent. The transverse colon showed a stricture between its right 2/3rd and left 1/3rd, confirming with vascular accidents, resulting in anomalous blood supply and aganglionosis. The dilated part of the sigmoid colon was found to be with ganglion cells, while the distal part after the megacolon, lacked ganglion cells in all layers of the sigmoid colon. This case documents a very rare finding which will make the surgeons aware of a newer arterial pattern associated with congenital megacolon. KEYWORDS: Sigmoid colon, Hirschsprung’s disease, Arc of Riolan.

Collateral aortic branches in the collared peccary (Pecari tajacu Linnaeus, 1758).

The determination of arterial vascular distribution patterns can contribute to more detailed knowledge on arterial systems. In this context, the aim of the present study was to describe the collateral aortic branches in the collared peccary, aiming to define a standard model for this species, providing information through comparative anatomy for analysis of some evolutionary aspects of the order Artiodactyla. Ten young male animals were employed. The vascular system was washed with a saline solution and then perfused with Neoprene 450 latex coloured with red or yellow pigment, followed by collateral aorta branch dissections and analyses. The contrasted digital radiography technique was applied to two animals, which were initially perfused with a barium sulphate solution (1 g/ml) and Neoprene 450 latex at a 1:3 ratio, and subsequently, the digital radiographic examination was performed. The aortic arch of the collared peccary emitted the brachiocephalic trunk and the left subclavian artery, while eight symmetric pairs of dorsal intercostal arteries originated from the thoracic aorta. The abdominal aorta, in turn, exhibited the celiac, cranial mesenteric, renal, caudal mesenteric, testicular, external iliac, internal iliac and sacral arteries as the collateral branches in all studied animals. Therefore, no relevant variations were observed regarding the arrangement of the arterial distribution of the aorta, thus suggesting a static standard model in the collared peccary.

Anatomical variants in prostatic artery embolization in treatment of benign prostatic hyperplasia

BackgroundBenign prostatic hyperplasia (BPH) is the most prevalent benign tumor in aged men, and its prevalence is rising with age reaching 8% in the fourth decade of life and up to 90% in the ninth decade. PAE has long been considered as a safe and effective minimally invasive therapy option for individuals with moderate to severe lower urinary tract symptoms caused by prostatic hypertrophy. Because of the varying degrees of atherosclerosis seen in the elderly, PAE is generally a difficult treatment that necessitates a particular amount of knowledge of anatomy and a specific set of abilities. It is critical to emphasize anatomical information about PA that is required for a successful PAE, as well as radiation exposure factors that can be helpful in such a protracted treatment. This thesis provides a pictorial review of PA anatomy and prevalence of related anatomical variants, besides additional anatomical and radiation dosage concerns, and knows the important effect of the anastomosis on non-target embolization as in our study we included large number of cases (83 patients) to cover all types of variations and different types of anastomosis all were covered.ResultsA total of 83 patients (166 sides) were analyzed. Double arterial supply on the same side was noted in 1 patient (1.2%). In 3 patients (3.6%), only a unilateral PA was identified. PA origin frequencies were computed. Penile, rectal, vesical anastomoses, and anastomosis with the other side were identified with 7 (8.4%), 3 (3.6%), 2 (2.4%), and 8 (9.6%) of PAs, respectively. Mean skin radiation dose was 479 mGy.ConclusionsWhen treating BPH with PAE, understanding PA anatomy is critical for achieving the best results. The anatomy of the PA is critical for preventing non-target embolization and is directly related to the correct identification of the anatomical pattern of the prostate arteries, and we should also take into account the presence of contralateral anastomoses; it is possible to achieve both prostate lobes through catheterization of the prostatic artery on only one side.

Hybrid Leg Revascularization: Remote Endarterectomy and Deep Vein Bypass to Posterior Tibial Artery

Early endovascular intervention for intermittent claudication is a common practice and is associated with progression to chronic limb-threatening ischemia and elevated amputation risk. When failure for this common approach ultimately occurs, the result is a complex arterial occlusive pattern. Coupled with absent autologous vein conduit, the risk of amputation for this patient profile is high. Remote endarterectomy with endovascular stent explant is a reliable technique to treat chronic total occlusion of the superficial femoral artery (SFA) and restore inflow.

Analysis of the Variations in the Colic Branching Pattern of the Superior Mesenteric Artery: A Cadaveric Study With Proposal to Modify Its Current Anatomical Classification

Background: Vascular anatomy of the ascending colon is more complex and variable as compared to the left. Variations range from the mode of origin, branching to territorial supply. The present study was undertaken to learn the anatomical variations of the superior mesenteric artery (SMA) and its colic branches in detail.Materials and methods: The study included 50 formalin fixed cadavers aged between 40 and 65 years. The colic branches arising from SMA were dissected to trace their mode of origin, branching pattern, and territorial supply. Based on the mode of origin of the colic branches, the SMA anatomy was classified into four patterns: I; II a, b, c; III; and IV.Results: SMA itself showed variations in its origin (as celiacomesenteric and hepatomesenteric trunk), so the colic branches arising from it. In most of the cases, middle (MCA), right (RCA), and ileocolic artery (ICA) originated independently from SMA (I). A common stem (CS) was reported between MCA and RCA (IIa) in seven cases; RCA and ICA in one (IIb); MCA and LCA in one. MCA originated from the coeliac trunk (CT) in one case. In one case, each of absent RCA (III) and accessory artery arising from SMA (IV) was also noticed. In one case, the right branch of MCA gave origin to RCA. Additionally, close association was observed between pattern IIa and incomplete inter-colic anastomosis.Conclusion: Variations in the origin of SMA may potentially influence branching patterns of colic arteries. MCA is the most variant and ICA is the most consistent branch of SMA. Distinctive variations like MCA arising from CT or arising as CS with LCA and incomplete inter-colic anastomosis in pattern IIa are of outrageous importance for operating surgeons during surgical procedures of colon. Based on study results, we propose a modification in the classification of SMA anatomy to include the CS of MCA and LCA as type IId; however, its success relies upon universal acceptance.

Variations in origin of inferior pancreaticoduodenal artery

Coeliac trunk and Superior Mesenteric arteries are very much susceptible to variations and were described by Tandler in 1904. Abdominal aorta branches are classified as single double or visceral parietal. Double visceral branches are middle suprarenal, renal and testicular arteries and single visceral branches are coeliac trunk, superior mesenteric and inferior mesenteric arteries. Materials and Methods: After obtaining ethical committee approval, we observed the origin, course and branching pattern of pancreatico duodenal arteries in 50 cadavers kept for dissection from 2019-2022 in Rohilkand Medical College and Hospital and Ayaan Institute of Medical Sciences. Results: In a male cadaver aged approximately 60 years, we observed that inferior pancreatico duodenal artery is absent. In another male cadaver aged about 70 years, we observed an additional inferior pancreatico duodenal artery. In remaining specimens, we observed the branching pattern very much normal.