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Clin Anat. 2012 Jul ;25 (5):609-18
21976364
Department of Anatomy, Otago School of Medical Sciences, University of Otago, Dunedin, New Zealand. mark.stringer@anatomy.otago.ac.nz.
The internal and external vertebral venous plexuses (VVP) extend the length of the vertebral column. Authoritative sources state that these veins are devoid of valves, permitting bidirectional blood flow and facilitating the hematogenous spread of malignant tumors that have venous connections with these plexuses. The aim of this investigation was to identify morphologic features that might influence blood flow in the VVP. The VVP of 12 adult cadavers (seven female, mean age 79.5 years) were examined by macro- and micro-dissection and representative veins removed for histology and immunohistochemistry (smooth muscle antibody staining). A total of 26, mostly bicuspid, valves were identified in 19 of 56 veins (34%) from the external VVP, all orientated to promote blood flow towards the internal VVP. The internal VVP was characterized by four main longitudinal channels with transverse interconnections; the maximum caliber of the longitudinal anterior internal VVP veins was significantly greater than their posterior counterparts (P < 0.001). The luminal architecture of the internal VVP veins was striking, consisting of numerous bridging trabeculae (cords, thin membranes and thick bridges) predominantly within the longitudinal venous channels. Trabeculae were composed of collagen and smooth muscle and also contained numerous small arteries and nerve fibers. A similar internal venous trabecular meshwork is known to exist within the dural venous sinuses of the skull. It may serve to prevent venous overdistension or collapse, to regulate the direction and velocity of venous blood flow, or is possibly involved in thermoregulation or other homeostatic processes. Clin. Anat. 25:609-618, 2012. © 2011 Wiley Periodicals, Inc.
Other papers by authors:
ANZ J Surg. 2012 Sep 17;:
22985390
Department of Anatomy, Otago School of Medical Sciences, Dunedin, New Zealand.
BACKGROUND: Gallstone disease is a worldwide problem causing morbidity, mortality and a drain on health-care resources. This prospective study aimed to investigate the spectrum of gallstone types in New Zealand and relate these to known risk factors. METHODS: Gallstone samples were collected from 107 patients undergoing surgery for gallstone disease at Auckland City Hospital between June 2009 and June 2010. Detailed chemical analyses were performed using Fourier Transform Raman spectroscopy. The relationship between gallstone type and age, gender, ethnicity, obesity and positive family history were analysed. RESULTS: Median age was 51 years (range 19-88), 75 (70%) were female, one third were obese (body mass index ≥ 30) and 41% had a positive family history. Major ethnic groups were European (51%), Asian (23%) and Māori/Pacific (18%). Gallstone types included pure or mixed cholesterol stones (74%), black pigment stones (20%) and brown pigment stones (5%). Asians had a higher proportion of black pigment stones and NZ Europeans had more cholesterol and mixed cholesterol stones (odds ratio 3.6 (95% CI 1.1 to 11.5)). The frequency of cholesterol/mixed cholesterol stones was not significantly different between NZ Europeans and Māori/Pacific groups (P = 0.7). Black pigment stones were more common in older patients (mean 68.0 years compared with 47.6 for cholesterol/mixed cholesterol stones)(P = 0.0001). There was no significant relationship between stone type and family history (P = 0.16) or gender (P = 0.17). CONCLUSION: This novel prospective study highlights risk factors and ethnic differences in gallstone composition in New Zealand. These may be important when considering gallstone prevention strategies.
N Z Med J. 2012 ;125 (1361):37-45
22960714
Department of Anatomy, Otago School of Medical Sciences, University of Otago, PO Box 913, Dunedin, New Zealand. mark.stringer@anatomy.otago.ac.nz.
AIMS Ultrasound is a safe, non-invasive and versatile imaging modality used widely in clinical practice. Several studies have reported using ultrasound imaging to supplement teaching of clinical anatomy to medical students but most have attempted to teach basic ultrasound skills in addition to normal sonographic anatomy. These small group teaching sessions are labour intensive and need appropriate resourcing of equipment and personnel. We report experience of an alternative approach suitable for large classes with more limited resources. METHODS A single 1-hour ultrasound demonstration of 'living anatomy' of the abdomen, pelvis and neck was conducted using a young female model as the subject. Scans were performed by an experienced sonographer with images projected on to a large lecture theatre screen; medical student interaction was encouraged by two clinical anatomists. RESULTS Anonymous evaluation of 152 returned questionnaires (greater than and equal to 63% response rate) showed that more than 80% of respondents considered the session had stimulated and improved their understanding of anatomy. CONCLUSIONS Whilst this method of teaching anatomy using ultrasound does not offer hands-on experience, it does provide students with an introduction to the clinical utility of ultrasound and, by focusing on anatomic findings rather than the acquisition of technical imaging skills, reinforces the learning of clinical anatomy.
Clin Anat. 2012 Aug 24;:
22926984
Otago School of Medical Sciences, Department of Anatomy, Dunedin, Otago, New Zealand. abigail.moore@anatomy.otago.ac.nz.
J Clin Neurosci. 2012 Aug 14;:
22901503
Department of Anatomy, Otago School of Medical Sciences, University of Otago, PO Box 913, Dunedin, New Zealand.
Clin Anat. 2012 Aug 7;:
22887313
Department of Anatomy, Otago School of Medical Sciences, University of Otago, Dunedin, New Zealand.
Clin Anat. 2012 Jul 31;:
22855456
Department of Anatomy, Otago School of Medical Sciences, University of Otago, Dunedin, New Zealand. mark.stringer@anatomy.otago.ac.nz.
Clin Anat. 2012 Jul 26;:
22836507
Department of Anatomy, Otago School of Medical Sciences, University of Otago, Dunedin, New Zealand.
Vertebral levels of key landmarks in the neck are well documented in anatomy texts but are they accurate? This study aimed to investigate the vertebral levels of the hard palate, hyoid bone, thyroid cartilage, cricoid cartilage, and bifurcation of the common carotid artery (CCA) using computed tomography (CT). After excluding patients with distorting pathology, 52 CT scans of the neck from supine adults with a standardized head position (mean age 63 ± 17 years, range 30-94 years; 21 female) were available for analysis by dual consensus reporting. Only the vertebral level of the hard palate (C1) was consistent with contemporary descriptions. Other landmarks were located most frequently at the following vertebral levels: the center of the body of the hyoid bone at C4 (54% of cases); the superior limit of the laminae of the thyroid cartilage at C4 in women (60%) and C5 in men (52%)(P = 0.02); the inferior border of the cricoid cartilage in the midline anteriorly at C6 in women (37%) and C7 in men (47%)(P = 0.008); and the bifurcation of the left and right common carotid arteries at C3 (left 56%, right 62%). The bifurcation of the CCA was a mean of 1.6 ± 1.2 cm above the superior border of the thyroid laminae. Vertebral levels of key bony/cartilaginous structures in the neck differ from standard descriptions but in the absence of a standardized cervical axial plane have limited value and clinical utility. Clin. Anat. 2012. © 2012 Wiley Periodicals, Inc.
Clin Anat. 2012 Jun 28;:
22744875
Department of Anatomy, Otago School of Medical Sciences, University of Otago, Dunedin, New Zealand.
Descriptions of clinically important surface landmarks often vary between and within contemporary anatomical texts. The aim of this study was to investigate the surface anatomy of major abdominal vessels, kidneys, spleen, gastroesophageal junction, and duodenojejunal flexure in living adults using computed tomography (CT). After excluding patients with distorting space-occupying lesions, scoliosis, abnormal lordosis, and obvious visceromegaly, 108 abdominal CT scans of supine adults (mean age 60 years, range 18-97 years; 64 female) at end tidal inspiration were available for analysis by dual consensus reporting. Intra-observer agreement was assessed by repeat blind assessment of a random sample of scans. The vertebral level of the aortic bifurcation and almost all of its major branches, and the origin of the inferior vena cava were consistent with current descriptions. Important differences from contemporary descriptions of surface anatomy were as follows: the renal arteries were most commonly at the L1 vertebral level (left 55%, right 43%); the midpoint of the renal hila was most frequently at L2 (left 68%, right 40%); the 11th rib was a posterior relation of the left kidney in only 28% of scans; and the spleen was most frequently located between the 10th and 12th ribs (48%) with its long axis in line with the 11th rib (55%). Although the majority of vascular surface landmarks are consistent with standard descriptions, the surface anatomy of the kidneys, renal arteries, and spleen needs to be revised in accordance with observations using modern imaging techniques in vivo. © 2012 Wiley Periodicals, Inc.
Clin Anat. 2012 Jun 4;:
22674662
Department of Anatomy, Otago School of Medical Sciences, University of Otago, Dunedin, New Zealand.
Anatomical planes used in clinical practice and teaching anatomy are largely derived from cadaver studies. Numerous inconsistencies in clinically important surface markings exist between and within anatomical reference texts. The aim of this study was to reassess the accuracy of common anatomical planes in vivo using computed tomographic (CT) imaging. CT scans of the trunk in supine adults at end tidal inspiration were analyzed by dual consensus reporting to determine the anatomy of five anatomical planes: sternal angle, transpyloric, subcostal, supracristal, and the plane of the pubic crest. Patients with kyphosis, scoliosis, or abnormal lordosis, distorting space-occupying lesions, or visceromegaly were excluded. Among 153 thoracic CT scans (mean age 63 years, 53% female), the sternal angle was most common at T4 (females) or T4/5 (males) vertebral level, and the tracheal bifurcation, aortic arch, and pulmonary trunk were most often below this plane. In 108 abdominal CT scans (mean age 60 years, 59% female), the subcostal and supracristal planes were most often at L2 (58%) and L4 (69%), respectively. In 52 thoracoabdominal CT scans (mean age 61 years, 56% female), the transpyloric plane was between lower L1 and upper L2 (75%); in this plane were the superior mesenteric artery (56%), formation of the portal vein (53%), tip of the ninth rib (60%), and the left renal hilum (54%), but the right renal hilum and gallbladder fundus were more often below. The surface anatomy of anatomical planes needs revising in the light of results from living subjects using modern imaging techniques. Clin. Anat. 2012. © 2012 Wiley Periodicals, Inc.
Clin Anat. 2012 May 10;:
22576938
Department of Anatomy, Otago School of Medical Sciences, University of Otago, Dunedin, New Zealand.
Accurate surface anatomy is essential for safe clinical practice. Numerous inconsistencies in clinically important surface markings exist between and within anatomical reference texts. The aim of this study was to investigate key thoracic surface anatomical landmarks in vivo using computed tomographic (CT) imaging. High-resolution thoracic CT scans from 153 supine adults (mean age 63, range 19-89 years; 53% female) taken at end tidal inspiration were analyzed by dual consensus reporting to determine the surface anatomy of the sternal angle, central veins, heart, lungs, and diaphragm. Patients with kyphosis/scoliosis, distorting space-occupying lesions, or visceromegaly were excluded. The position of the cardiac apex, formation of the brachiocephalic veins, and vertebral levels of the sternal angle, xiphisternal joint, and aortic hiatus were consistent with commonly accepted surface markings although there was a wide range of normal variation. In contrast, common surface markings were markedly inaccurate for the following: the position of the tracheal bifurcation, aortic arch, and azygos vein termination (below the plane of the sternal angle at T5-T6 vertebral level in most individuals); the superior vena cava/right atrial junction (most often behind the fourth costal cartilage); the lower border of the lung (adjacent to T12 vertebra posteriorly); and the level at which the inferior vena cava and esophagus traverse the diaphragm (T11 in most). Surface anatomy must be reappraised using modern imaging in vivo if it is to be evidence based and fit for purpose. The effects of gender, age, posture, respiration, build, and ethnicity also deserve greater emphasis. Clin. Anat. 2012. © 2012 Wiley Periodicals, Inc.
Latest similar papers:
Department of Radiodiagnosis, Dr Rajendra Prasad Government Medical College-Tanda, Set No A3, Type IV Quarters, Kangra, Himachal Pradesh, India. narvirschauhan@yahoo.com
Emissary veins are valveless veins which pass through the cranial apertures and connect the dural venous sinuses and the extracranial veins. The clinical importance of emissary veins is increasingly being appreciated. Some emissary veins like the petrosquamosal sinus and mastoid emissary vein may cause significant bleeding during middle ear and skull base surgeries. A dilated mastoid emissary vein or condylar emissary vein can sometimes be a rare cause of tinnitus. Radiological identification of these venous channels has been described in recent years and assumes significance in light of their clinical importance. We describe the CT and MRI findings of a rare case that had persistence of multiple emissary veins and presented clinically with tinnitus. The radiological findings included a dilated left mastoid emissary vein, bilateral petrosquamosal sinuses, posterior condylar veins, occipital emissary veins and an intrapetrous venule. The left petrosquamosal sinus had an unusual origin from the dilated mastoid emissary vein. The patient also had major anomalies of posterior fossa venous sinuses which are discussed. A relevant review of literature is included.
J Morphol. 2011 Mar ;272 (3):280-6
21312227
Anatomy and Histology, Department of Biomedical Sciences, Stellenbosch University, South Africa. shk@sun.ac.za
Bathyergus suillus are subterranean rodents found in the Western Cape of South Africa, where they inhabit sandy, humid burrows. Vertebral venous plexuses around the vertebral column have been implicated in aiding the maintenance of a constant central nervous system temperature via its connections with muscles and interscapular brown adipose tissue. The morphology of the vertebral venous plexuses and its connections in B.suillus were investigated. Frozen (n = 10) animals were defrosted; the venous system injected with latex and the vertebral venous plexuses, azygos- and intercostal veins dissected along the dorsal and ventral aspects of the vertebral column. Specimens (n = 4) were used for histological serial cross sections of the thoracic vertebrae. Veins drained from the interscapular brown adipose tissue to the external vertebral venous plexus, via a dorsal vein at the spinous process of T2 which might represent the "vein of Sulzer" described in rats. The intercostal veins cranial to the level of T8 drained directly into the ventral external vertebral venous plexus instead of into the azygos vein as seen in rats. The azygos vein was situated ventrally on the thoracic vertebral bodies in the median plane as opposed to most rodents that have a left sided azygos vein. The internal vertebral venous plexus consisted of two ventrolateraly placed longitudinal veins in the spinal epidural space. Veins from the forelimbs entered the internal vertebral venous plexus directly at the levels of C7 and T1 and have not been described in other rodents. Serial histological sections, revealed no regulatory valves in vessels leading toward the internal vertebral venous plexus, allowing blood to presumably move in both directions within the vertebral venous plexus. The vertebral venous plexus of B. suillus shows similarities to that of the rat but the vessels from the forelimbs draining directly into to the internal vertebral venous plexus and the position of the azygos vein and the intercostal veins draining into the external vertebral venous plexus are notable exceptions.
Daniele Zaccone,
Adrian C Grimes,
Alessandra Sfacteria,
Marta Jaroszewska,
Giuseppa Caristina,
Mauro Manganaro,
Anthony P Farrell,
Giacomo Zaccone,
Konrad Dabrowski,
Fabio Marino
Department of Animal Biology and Marine Ecology, Faculty of Science, University of Messina, Italy.
Anatomical and functional studies of the autonomic innervation in the conus arteriosus of the garfishes are lacking. This study reveals that the conus arteriosus of the longnose gar is primarily myocardial in nature, but additionally, large numbers of smooth muscle cells are present in the subendocardium. A well-developed system of adrenergic, cholinergic, substance P (SP) and neuronal nitric oxide synthase (nNOS) positive nerve terminals are found in the wall of the conus arteriosus. Coronary blood vessels running in the adventitia receive a rich supply of nNOS positive nerve fibers, thus suggesting their importance in the nitrergic control of blood flow in the conus arteriosus. The present data show that the patterns of autonomic innervation of the garfish conus arteriosus are more complex than previously appreciated.
Department of Anatomy and Structural Biology, University of Otago, Dunedin, New Zealand.
HASH(0x27bc8ff0)
Department of Orthopaedic Surgery, Kochi University, Oko-cho Kohasu, Nankoku 783-8505, Japan.
OBJECTIVES This study aims to investigate the effects of thromboprophylactic transcutaneous electrical nerve stimulation (TpTENS) of the peroneal nerve on venous blood flow in the limbs of volunteers. TpTENS might be considered for use in preventing venous stasis during surgical treatment. METHODS In 10 volunteers, peak venous velocity (PV) and flow volume (FV) in the popliteal vein were measured using duplex ultrasonography during calf-muscle stimulation. The effects of TpTENS of the peroneal nerve were compared with those of other mechanical methods, including electrical muscle stimulation, intermittent pneumatic compression, active ankle motion and calf squeeze, used to prevent venous stasis and achieve thromboprophylaxis. RESULTS TpTENS had similar effects on popliteal vein blood flow in comparison with other established methods of thromboprophylaxis. The PV increased its basal flow by 3.9 times (p < 0.01) and FV by 2.7 times (p < 0.01), respectively, compared with baseline values. CONCLUSIONS TpTENS is as effective as other electrical and mechanical methods of calf-muscle pump activation in achieving acceleration of venous flow in the lower limb.
Department of Neurological Surgery, Oregon Health & Science University, Portland, Oregon 97239, USA.
The anterior condylar confluence (ACC) is located on the external orifice of the canal of the hypoglossal nerve and provides multiple connections with the dural venous sinuses of the posterior fossa, internal jugular vein, and the vertebral venous plexus. Dural arteriovenous fistulas (DAVFs) of the ACC and hypoglossal canal (anterior condylar vein) are extremely rare. The authors present a case involving an ACC DAVF and hypoglossal canal that mimicked a hypervascular jugular bulb tumor. This 53-year-old man presented with right hypoglossal nerve palsy. A right pulsatile tinnitus had resolved several months previously. Magnetic resonance imaging demonstrated an enhancing right-sided jugular foramen lesion involving the hypoglossal canal. Cerebral angiography revealed a hypervascular lesion at the jugular bulb, with early venous drainage into the extracranial vertebral venous plexus. This was thought to represent either a glomus jugulare tumor or a DAVF. The patient underwent preoperative transarterial embolization followed by surgical exploration via a far-lateral transcondylar approach. At surgery, a DAVF was identified draining into the ACC and hypoglossal canal. The fistula was surgically obliterated, and this was confirmed on postoperative angiography. The patient's hypoglossal nerve palsy resolved. Dural arteriovenous fistulas of the ACC and hypoglossal canal are rare lesions that can present with isolated hypoglossal nerve palsies. They should be included in the differential diagnosis of hypervascular jugular bulb lesions. The authors review the anatomy of the ACC and discuss the literature on DAVFs involving the hypoglossal canal.
Tissue Cell. 1990 ;22 (4):547-69
18620321
Cit:4
Department of Biological Sciences, University of California, Riverside, California 92521, U.S.A.
Injections of dye, latex and India ink were used to reveal the path of hemolymph circulation through the scorpion booklungs. Fine, branched arteries carry blood directly to muscle and other organs. The blood returns through venous channels to the ventral mesosoma where it passes laterally through the booklungs and into the pneumocardial veins just beneath the pleural cuticle. Blood flows dorsally through these veins to the pericardial sinus and heart. The scorpion has four pairs of booklungs located in the anterior segments of the ventral mesosoma. Each booklung has a spiracle which opens into an atrium enclosed by cuticular membrane. Air passes from the atrium into the booklung lamellae. Agitation of the animal or application of CO(2) causes retraction of the anterior and posterior atrial membrane. This expands the atrial chamber and allows gas exchange in the booklung lamellae. The posterior atrial membrane has a specialized region which forms a springy valve. This normally closes the spiracle unless pulled open by contraction of the attached poststigmaticus muscle. The pectens and receptors within the atrium may mediate the responses to CO(2). Slender hypocardial ligaments containing muscle fibers extend from the heart (dorsal mesosoma) to the booklungs in the ventral mesosoma. Heart movements thus cause dorso-ventral movement of the booklungs. The significance of these movements is as yet unclear. They may increase ventilation, help force blood to the heart and/or agitate the blood and booklung lamellae and thereby aid gas exchange. Passage of blood through the booklungs is regulated by dorsal and ventral muscles attached to the atrium at the lateral edge of the booklung. Contraction of the ventral atrial muscle closes the excurrent channel for passage of blood from the booklung into the pneumocardial vein. Electrical stimulation of the segmentai nerves from the subesophageal and first three abdominal ganglia causes spiracle opening and contraction of muscles attached to the atrial membrane. A previous study showed that these same segmental nerves also modulate heart activity. They thus provide a major pathway for regulation of the respiratory and circulatory systems.
Ital J Anat Embryol. ;113 (1):1-8
18491449
Cit:1
Veronica Macchi,
Andrea Porzionato,
Massimo Iafrate,
Ejituru Ebugheme,
Antonio Paoli,
Enrico Vigato,
Anna Parenti,
Vincenzo Ficarra,
Walter Artibani,
Raffaele De Caro
Department of Human Anatomy and Physiology, University of Padova, Italy.
Varicocele, a dilatation of the pampiniform plexus and/or the intrascrotal tract of the internal spermatic veins, is considered as a potential cause of male infertility. The mechanism of varicocele development is yet an object of debate. Aim of the work was to analyse the structure of the internal spermatic veins in 13 normal subjects (mean age: 26 years old) and its modification in 24 subjects with different grades of varicocele (mean age: 25.5 years old) through a morphological study. The presence of apoptotic cells was also evaluated by the terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) assay. The wall of the pampiniform plexus veins is constituted by a complex smooth muscle structure, organized in longitudinal bundles of smooth muscle cells within the tunica adventitia (median thickness of 95micron) and circularly running smooth muscle cells within the tunica media (median thickness of 120micron). Obliquely running muscle fibers bridge the outer longitudinal bundles of smooth muscle cells and the inner circular smooth muscle layer of the venous wall. The coordinated activity of such muscular structure is responsible for the propulsive mechanism which allows the antigravitational blood flow towards the left renal vein and the inferior vena cava. The reduction of the outer longitudinal and of the intermediate oblique smooth muscle cells, the increase of connective component and decrease of the circular smooth muscle cells of the tunica media are the main morphological changes that can be found in the wall of the spermatic veins of the patients with varicocele.
Morfologiia. 2006 ;130 (6):51-5
17338217
Changes of liver blood vessel structure were studied in 23 pups with the model of compensated pulmonary trunk stenosis and in 8 animals with decompensated stenosis during 6-24 months after the establishment of stenosis. The liver of 10 age-matched dogs was used as a control. Material was studied using histological, morphometric and stereometric methods. It was found that after the establishment of pulmonary trunk stenosis and compromise to venous blood outflow from the liver, the tone of the arteries increased as well as the resistance to the blood flow. Besides the venous-arterial reaction, the bundles of oblique-longitudinal smooth muscle cells and musculo-elastic sphincters were shown to be formed in the intima of the afferent vessels, while in the efferent vessels the hypertrophy of the muscular folds took place. In decompensated stenosis, the hypoxia was combined with the relaxation of the walls of both afferent and efferent vessels, the number of arteries with the adaptational structures was decreased, while the muscular folds of hepatic veins underwent atrophy. The failure of adaptation mechanisms resulted in the development of chronic liver venous congestion.
Eur Neurol. 2006 ;56 (2):136-8
16960456
Cit:4
Emeritus Consultant Neurologist, Department of Neurology, Hull Royal Infirmary, Hull, UK.
The valveless craniospinal venous system consists of veins and plexuses that communicate freely and whose flow is bidirectional. It comprises (1) the intracranial-cortical veins, dural sinuses, cavernous sinuses and ophthalmic veins, and (2) the vertebral venous plexuses, which freely anastomose with the intracranial venous system. The vertebral venous plexuses anastamose with the sacral, pelvic and prostatic venous plexus. It is clinically important since it provides a route for the spread of tumours, infection or emboli. This route may go unrecognised.
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