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An overview of the autonomic nervous system is given. The sympathetic innervation of the upper limb is presented, with specific emphasis on segmental nervous supply and anatomical variations. In addition, the physiology and pharmacology of the sympathetic nervous system is introduced and discussed.
The utilization of partial-liver grafts for transplantation of adults represents an evolution from strategies designed to increase pediatric organ supply that have been justified by increased organ-waiting times and morbidity of adult transplant candidates. These techniques, which include adult-to-adult living-donor and split-liver transplantation, mandate particular surgical and medical considerations, as partial-liver grafts predispose to unique complications resulting from anatomic variations, technical considerations, and recipient physiology. Adult-to-adult living-donor liver transplantation has been successfully reported throughout the world; however, the magnitude of the donor operation has resulted in serious morbidity and donor mortality that have stimulated an ethical debate as to the future of this procedure. The limitations encountered in the application of adult-to-adult, living-donor liver transplantation have renewed interest in the successful implementation of split-liver transplantation between two adults from one adult cadaver donor. This manuscript details current technical considerations for the performance of adult-to-adult living-donor and split-liver transplantation, summarizes current outcomes, and explores the ethical dilemma of living-donation.
Transesophageal echocardiography (TEE) is the most common imaging modality for the detection of acute aortic syndromes. However anomalous anatomic structures may be occasionally misunderstood as pathologic due of lack of familiarity with anatomical variations; false-positive diagnosis can result, potentially leading to unnecessary surgical intervention. It is crucial for echocardiographers to be aware of possible pitfalls which may create false positive findings, since the complementary use of other imaging modalities, such as multislice spiral computed tomography (MSCT), could improve the diagnostic accuracy of TEE. We report a case in which an image resembling an acute aortic dissection (AAD) on transthoracic (TTE) and transesophageal echocardiography was found in a patient with acute chest pain; MSCT detected an anomalous origin of the right coronary artery as cause of false aortic dissection image at echocardiography.
PURPOSE: EMD 121974, a potent cyclic RGD peptide inhibitor of alphav-integrins, demonstrated effectiveness in suppressing brain tumor growth in both preclinical models and phases I/II clinical trials. The ability to non-invasively evaluate alphav-integrin expression provides a novel and unique way to better understand brain tumor angiogenesis in relationship to alphav-integrin expression, and allow for direct assessment of anti-integrin treatment efficacy. PROCEDURES: We developed a F-18-labeled RGD peptide [F-18]FB-RGD and performed serial microPET imaging scans to follow brain tumor growth and angiogenesis as a function of time in an orthotopic U87MG glioblastoma xenograft model in athymic nude mice. RESULTS: The tumor was barely visible on microPET at the size of <or=1.5 mm diameter at which time no angiogenesis was evident on histological examination. When tumor started to grow exponentially by day 35 the activity accumulation in the brain tumor also increased accordingly, with best tumor-to-brain contrast seven weeks after inoculation of 10(5) U87MG cells into the mice forebrain. CONCLUSIONS: Longitudinal microPET imaging and [F-18]FB-RGD provides the sensitivity and resolution to visualize and quantify anatomical variations during brain tumor growth and angiogenesis, most likely through interaction with alphav-integrins expressed on tumor cells and angiogenic tumor vessels.
The usefulness of subclassifying the anatomic variations of straddling and overriding atrioventricular (AV) valve by 2-dimensional echocardiographic observation were evaluated. Chordae straddling into a contralateral ventricle were subdivided into type A (chordae inserting into the contralateral ventricle near the crest of the ventricular septum), type B (chordae inserting along the contralateral ventricular septum) and type C (chordae inserting into the free wall or papillary muscles of the contralateral ventricle). Overriding AV valve anulus was described as minor (less than 50% of the anulus committed to the contralateral ventricle), major (about 50% of the anulus committed to each ventricle), and double-inlet ventricle (greater than 50% of both AV valves committed to a single ventricular chamber). In 52 patients straddling AV valve was diagnosed by echocardiography and confirmed by direct examination at surgery or autopsy. In 60 of 66 straddling AV valves (91%), the diagnosis and the degree of straddling (type A, B or C) were correctly identified by 2-D echocardiography. Major associated cardiac defects included double-outlet right ventricle (31%), complete transposition (23%), corrected transposition (19%), double-inlet ventricle (19%) and other complex defects (8%). Twenty-two patients (42%) had right-sided straddling, 21 (40%) had left-sided straddling and 9 (17%) had straddling of both AV valves. In 41% of the patients, straddling AV valve had a major impact on the type of surgery or the surgical outcome. Of these valves, 52% were type C (severe), 26% type B and 22% type A straddling.(ABSTRACT TRUNCATED AT 250 WORDS)
Electrocardiographically gated magnetic resonance imaging (MRI) was successfully performed in 9 patients with atrioventricular (AV) septal defect: 6 had complete AV canal and 3 had partial AV canal. The defect was readily visualized in all patients on transverse scans taken at the level of the AV valve. The size and extent of the defect could be easily determined. All patients demonstrated a similar underlying morphologic pattern on MRI scans, consisting of deficiency of the primum atrial septum and inlet ventricular septum and a "common" AV valve ring with absence of the cardiac crux. The 3 patients with isolated atrial septal defect could be distinguished from the 6 with complete AV canal by the dense, fibromuscular bridging tissue, which coursed from the AV valve to the crest of the ventricular septum, obliterating the interventricular communication. Four patients had angiographically proved ventricular hypoplasia, which was also detected by MRI. AV valves and their patterns of chordal attachment were accurately imaged in 7 patients on systolic sections; accessory chordae were identified in 6 patients. MRI is a useful noninvasive imaging modality that can depict the underlying morphologic abnormalities in AV septal defect as well as important anatomic variations.
Twenty-two hirsute women underwent percutaneous adrenal and ovarian vein catheterization to differentiate and localize excessive hormonal output. All studies were done under fluoroscopic control; catheter placement was verified by venography, and blood samples were withdrawn for hormonal analysis. The right ovarian vein was successfully sampled in 42 per cent of attempts; the left ovarian vein, in 75 per cent; the right adrenal vein, in 56 per cent; and the left adrenal vein, in 100 per cent. Bilateral catheterization did not prove clinically useful. First, anatomic variations in venous size and drainage made catheterization and bilateral sampling difficult. Second, adrenal secretion is both episodic and parallel, necessitating both simultaneous catheterization and serial sampling for adequate diagnosis. The stress of the procedure may provoke increased adrenal output. Third, since ovarian secretion is not parallel, and since increased hormone output has been documented in that ovary containing developing follicles or a corpus luteum, distinguishing ovarian dysfunction proved difficult. Finally, for a time-consuming procedure, patient discomfort cannot be disregarded. This technique has not proved to be a reliable means of determining the site of androgen hypersecretion and thus cannot be recommended in the routine evaluation of female hirsutism.
This communication describes a technique of sonographically monitored uterine curettage. This method is of particular value in the management of postabortal endomyometritis associated with retained products of conception or in any situation in which anatomic variation (for instance, retroversion) makes curette insertion difficult.
1. Of forty-one patients with biliary tract problems studied by endoscopic retrograde choledochopancreatography, interpretation of ductograms or endoscopic observations in ten could not be accomplished with ease for one or several reasons. 2. Although incomplete filling of the bile ducts usually signifies organic obstruction, this occasionally is not true. The specific origin and histologic character of the lesion causing bile duct obstruction are not delineated by retrograde endoscopic cholangiography. 3. Other occasional limitations of endoscopic cholangiography include difficulties in demonstrating minute stones, in recognizing confusing anatomic variations, and in defining the status of recurrent strictures. 4. Inflammatory changes in the duodenal papilla can simulate carcinoma, or vice versa, on the basis of observation by the endoscopist. The capability of achieving a pancreatogram does not rule out the presence of carcinoma at the ampulla producing jaundice. Current technics for biopsy of the papilla or ampulla are in some instances inadequate, making results of such procedures unreliable. 5. Although endoscopic retrograde cholangiopancreatography frequently permits acquisition of vital information for the surgeon and occasionally provides unexpected information of significance, interpretative difficulties in some instances always necessitate the correlation of findings with other available clinical information.
Radioimmunoassay of parathyroid hormone on samples obtained from the large veins of the neck and thorax was utilized for localization in twenty-one patients with hyperparathyroidism. In seventeen of these patients, as many of the thyroid and mediastinal veins as possible were also sampled. This study reveals that sampling of the large veins of the neck and thorax is an insensitive means of adenoma from hyperplasia. Anatomic variations in the drainage of the inferior thyroid veins and dilution of the parathyroid venous effluent by the large veins of the neck and thorax seem to explain this insensitivity and the occasionally misleading results of large vein sampling. Sampling of the small thyroid veins, however, is a sensitive and specific means of localization and permitted preoperative differentiation of adenoma from hyperplasia in fourteen of our seventeen patients. Communications between the inferior thyroid and thymic veins and the fact that mediastinal adenomas frequently bring their blood supply down from the cerevical area suggest that sampling of the small thyroid veins may be of only limited value in identifying a mediastinal adenoma.
Thirty-six of 403 deaths after tracheotomy were direct complications of that procedure. Arterial hemorrhage caused three deaths, venous bleeding, seven. Airway obstruction resulted in six fatalities. Tracheoesophageal fistula caused five deaths. Eight deaths were due to infection and sepsis. Tension pneumothorax developed in one patient and the remaining six deaths were due to cardiopulmonary collapse. Many of the complications of tracheotomy can be avoided with accurate knowledge of anatomic variations, ideal operating conditions, proper technic, careful arterial and venous hemostasis, routine postoperative chest x-ray films, sterile suction technic, proper use of soft cuffed tracheotomy tubes, adequate humidification, and careful postoperative blood gas monitoring.
A patient with an anomalous insertion of the right hepatic duct into the cystic duct was noted during cholecystectomy and confirmed by operative cholangiography. This case and related anomalies of the bile ducts are of sufficient importance that, because of the technical difficulties and dangers incidental to their presence, no surgeon who operates on the gallbladder and bile ducts can afford to be unaware of their existence. Adequate exposure, careful dissection, and accurate knowledge of the regional anatomy plus a realization of the frequency and multiplicity of abnormalities of the extrahepatic biliary tree are requisites for safe biliary tract surgery. In addition, carefully performed operative cholangiography can be an indispensable aid in the clarification of anatomic variations. In case of recognized operative injury to the extrahepatic biliary tree, primary repair or biliary-intestinal anastomosis can usually be carried out with good results.
Hypercalcemia with and without clinical manifestation appears to be diagnosed with increasing frequency. If hypercalcemia persists with no other obvious reasons, hyperparathyroidism can be suspected with a high degree of certainty. Surgical treatment requires confidence, patience and a thorough knowledge of the embryologic peculiarities and anatomic variations of these glands. In 88 percent of our 71 patients, a solitary benign parathyroid adenoma was diagnosed by light microscopy. Parathyroid four-gland hyperplasia was found in 5.6 percent of the patients and multiple adenoma in 3 percent. The cause of hypercalcemia was not found in 3 percent. All patients treated with parathyroidectomy responded well, with calcium levels returning to normal. Our results confirm that this conservative approach to parathyroidectomy without multiple gland biopsy is the better and more acceptable method of dealing with hyperparathyroidism. Multiple gland dissection biopsy, chest exploration and parathyroid implantation are necessary only in very difficult cases.
Abnormal persistent of the embryonic axial blood supply to the leg, the sciatic artery, is a rare but often clinically important condition. The sciatic artery may vary from a small collateral in the upper thigh to a very large vessel that is the leg's sole arterial blood supply. The abnormal artery is prone to aneurysmal dilatation and atherosclerotic occlusion, and different patterns of anatomic development in the sciatic and femoral artery systems pose significant diagnostic and therapeutic problems. Advances in preoperative hemodynamic assessment, arteriography, and vascular surgical technique have improved the results of management of persistent sciatic artery and its complications. The world literature has been reviewed, including one additional case, with emphasis on embryologic development, anatomic variations, and clinical presentation, as well as diagnosis, therapy, and results.
Heterotopic segmental pancreatic autotransplantation in dogs is more appropriate than allograft models for the investigation of several problems associated with transplantation. We have defined the anatomic variations of blood supply in the pancreatic tail and designed various modifications of vascular anastomosis to the iliac vessels in order to eliminate technical failures, such as thrombosis, as much as possible. In 187 of 240 dogs (77.9 percent), the pancreatic artery originated from the splenic artery and the pancreatic vein entered the splenic vein (normal anatomy). The main venous variation was direct confluence of the pancreatic and portal veins (12.1 percent), and the main arterial variation was origin of the pancreatic artery from the superior mesenteric artery (10 percent). Ninety-seven animals with normal anatomy qualified for a comparative study of seven methods of segmental pancreatic autotransplantation. Venous anastomoses were always performed in an end-to-side fashion between the splenic and external iliac veins. Arterial anastomosis techniques follow. Group I: interposition of the splenic artery into the external iliac artery; (14 days, failure rate 50 percent), Group II: end-to-end arterial anastomosis of the splenic artery to a long external iliac artery segment with the graft directed caudad, resulting in an acute curve to the vessel loop (8 dogs, failure rate 38 percent); Group III: end-to-end arterial anastomosis to a long external iliac artery with the graft directed cephalad, resulting in a gentle curve to the vessel loop (11 dogs, failure rate 36 percent); Group IV: end-to-end arterial anastomosis to a short external iliac artery stump (20 dogs, failure rate 20 percent); Group V: same as in Group IV with the addition of a distal splenic arteriovenous fistula (12 dogs, failure rate 17 percent); Group VI: end-to-side anastomosis of the splenic artery to the external iliac artery (31 dogs, failure rate 6 percent); Group VII: same as in Group VI but with the addition of an arteriovenous fistula of the distal splenic vessels (1 dog, failure rate 0). The end-to-side technique proved to be straight-forward and reliable. The low failure rate with this method allows metabolic preservation and other aspects of pancreatic transplantation to be studied and the results to be interpreted without the influence of a high complication rate from the operation itself.
The Greenfield filter can be used with a low complication rate provided one adheres to certain principles. First, preoperative venography to define the inferior vena caval anatomy will help avoid difficulties associated with anatomic variations. At the time the study is carried out, it would be extremely useful if the radiologist places a radiopaque marker at the level of the renal veins. This will ensure that filters will be placed in the infrarenal position when appropriate, thus preventing occasional inadvertent discharge, particularly into the right renal vein. Second, use of a guide wire greatly facilitates passage of the introducer and accurate intracaval positioning. Third, intraoperative technical errors must be recognized and promptly corrected. Finally, meticulous postoperative follow-up is essential, and recurrent embolism or any change in filter position requires repeat roentgenography of the vena cava to guide appropriate corrective treatment.
A modification of the technique of using the subclavian-sparing advancement flap for severe coarctation of the aorta was successfully used in 7 neonates ranging in age from 3 to 30 days (mean age, 12 days). Four of the 7 patients had associated cardiac defects with congestive heart failure. The procedure was performed through a left thoracotomy incision, and the coarctation repair was performed by advancing the origin of the left subclavian artery as a flap while preserving flow to the left arm. No deaths occurred, and there was patency of the repair in all patients at follow-up ranging from 1 1/2 to 2 1/4 years (mean, 2 years). In 7 of the 8 patients there was no clinically significant gradient either by examination or Doppler echocardiography at follow-up. One patient underwent balloon angioplasty at the time of catheterization to evaluate other cardiac defects 1 year postoperatively, at which time he was noted to have a peak systolic gradient of 30 mm Hg across the repair site. The technique of subclavian-sparing advancement is a reasonable addition to the surgical armamentarium for coarctation repair in neonates. It provides the advantages of subclavian flap aortoplasty without sacrificing the blood supply to the left arm. Because of the unique anatomic variations associated with coarctation of the aorta, we suggest that the choice of repair be individualized for patients with this condition.
We have examined 38 hearts with a double-outlet right ventricle with a subpulmonary ventricular septal defect. We divided the hearts into three groups according to the angle between the planes formed between the outlet septum and the remainder of the muscular ventricular septum; namely, at approximately right angles (15 hearts), parallel (11 hearts), and at an acute angle (12 hearts). The coronary arterial pattern corresponding to that seen in the normal heart was present in 11 hearts (73%) of the "right angle" group, in only one heart (8%) of the "acute angle" group, and in none of the "parallel" group. In contrast, the most common pattern in the setting of complete transposition was observed in none, 8%, and 91% of each group, respectively. Other diverse patterns were recognized in the hearts in the acute angle group, and the incidence of abnormal branching was significantly higher in this than in the other groups (p < 0.01). Knowledge of these anatomic variations in the course of the coronary arteries, some of which would cause problems at either definitive repair or reoperation, are essential for those seeking to achieve optimal surgical repair.