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PubMed1997

Diagnosis and operation for anomalous circumflex coronary artery.

BACKGROUND: Origin of the left circumflex coronary artery from the right sinus of Valsalva is the most common anatomic variation of the coronary artery circulation. However, there are few reports about the operative approach to this anomalous vessel. METHODS: Forty patients having this anomaly were identified from 10,216 adult cardiac catheterization procedures. Forty percent of the anomalous circumflex coronary arteries (ACCAs) had critical atherosclerotic lesions. Eighty cases needed bypass grafting. RESULTS: For diagnosis of ACCA, the aortic root sign was positive in 94.9% of the diagnosed patients and the nonperfused myocardium sign was found in 92.5%. Eighty percent of ACCAs were larger than 2 mm in radiographic diameter before their passage into the atrioventricular groove. However, after emerging from the atrioventricular groove, 70% measured less than 1.5 mm. Consequently, a technique was developed to bypass the proximal ACCA and was used in 2 cases. Six other patients with more distal disease and larger vessels underwent conventional bypass grafting. CONCLUSIONS: The aortic root sign and nonperfused myocardium are useful in diagnosing ACCA. The ACCA is usually too small for use of the conventional graft technique. Therefore, a technique was developed to graft more proximally and was applied successfully in 2 cases.

Adult↗

PubMed1998

Minimally invasive coronary artery bypass grafting: port-access approach versus off-pump techniques.

BACKGROUND: Within the past 5 years several surgical techniques have been developed for less invasive surgical treatment of coronary artery disease. The aim of this study was to define specific indications for the various minimally invasive coronary artery surgical procedures. METHODS: Minimally invasive direct coronary artery bypass grafting through a minithoracotomy was performed in 67 patients. The left internal mammary artery was anastomosed on the beating heart with the use of a pressure or suction stabilizer without the use of extracorporeal circulation. In 58 other patients with multivessel disease, the off-pump coronary artery bypass grafting technique through a sternotomy was applied with a left internal mammary artery to left anterior descending artery and additional vein grafts without extracorporeal circulation. In a third group, Port-Access (Heartport Inc, Redwood City, CA) coronary artery bypass grafting was performed through a left minithoracotomy with the use of an endovascular extracorporeal circulation system and cardioplegic arrest. Angiographic follow-up was complete in 64% of the patients. RESULTS: There was minimal perioperative or postoperative mortality (0.5%). The medium surgical procedure time for all minimally invasive and off-pump procedures was 2.5 hours; it was 4.5 hours for Port-Access procedures. The median postoperative intensive care unit stay was 1.0 days, and the median hospitalization was 5.0 days. Overall graft patency was 97.3%; in 8 patients (4.1%) a stenosis either at or distal to the graft anastomosis was dilated with coronary angioplasty. CONCLUSIONS: For single-vessel disease of the left anterior descending artery, the minimally invasive coronary artery bypass grafting procedure can be performed safely without the use of extracorporeal circulation. In case of hemodynamic instability or anatomic variation, the Port-Access procedure can be applied without additional necessity for sternotomy. For multivessel disease, the off-pump bypass grafting procedure with sternotomy can be recommended depending on the coronary arteries involved. In case of necessary grafts to the lateral marginal or circumflex branches, Port-Access grafting can be recommended and may play an important role in the future for the development of fully endoscopic robot-assisted coronary artery bypass grafting.

Adult↗

PubMed1998

Anatomy of inferior pulmonary vein should be clarified in lower lobectomy.

We successfully performed surgery for carcinoma of the lung on 2 patients with the anatomic variation of the middle lobe vein draining to the right inferior pulmonary vein. This variation is surgically important because division of the right inferior pulmonary vein may result in blockage of middle lobe vein drainage in right lower lobectomy. Surgeons must always pay attention to this variation when performing the right lower lobectomy.

Adenocarcinoma↗

PubMed2000

Structural basis of regional dysfunction in acutely ischemic myocardium.

OBJECTIVE: Impaired systolic function in the normally perfused myocardium adjacent to an ischemic region - the functional border zone - is thought to result from mechanical interactions across the perfusion boundary. We investigated how segment orientation and vessel involved affect regional strains in the functional border zone and whether altered stresses associated with a step transition in contractility can explain the functional border zone. METHODS AND RESULTS: Regional epicardial strain distributions were obtained from measured displacements of radiopaque markers in open-chest anesthetized canines, and related to local myofiber angles and blood flows. The functional border zone for fiber strain was significantly narrower than that for cross-fiber strain and significantly wider for left anterior descending (LAD) than left circumflex (LCx) coronary occlusion (1.23 vs. 0.45 cm). A detailed three-dimensional computational model with a one-to-one relation between perfusion and myofilament activation and no transitional zone of intermediate contractility showed close agreement with these observations and significantly elevated stresses in the border zone. Differences between LAD and LCx occlusions in the model were due to differences in left ventricular systolic pressure and not to differences in perfusion boundary or muscle fiber orientation. The border zone was narrower for fiber strain than cross-fiber strain because systolic stiffness is greatest along the muscle fiber direction. CONCLUSION: Abnormal regional mechanics in the acute ischemic border arise from increased wall stresses without a transitional zone of intermediate contractility. Perfusion is more tightly coupled to fiber than cross-fiber strain, and a wider functional border zone of fiber strain during LAD than LCx occlusion is primarily due to higher regional wall stresses rather than anatomic variations.

Actin Cytoskeleton↗

PubMed1991

The distribution of recurrent varicose veins: a phlebographic study.

One hundred consecutive legs in 74 patients presenting with recurrent varicose veins were investigated by varicography. Forty recurrences occurred at the groin, 80 in the thigh and 97 in the calf. Within each group different anatomical variations were encountered, and we describe the frequency of these and of certain commonly observed combinations. We also suggest possible causes, and discuss how the results of varicography may assist in surgical management.

Adult↗

PubMed1977

Coronary arteriography; method of presentation of the arteriogram report and a scoring system.

A coronary arteriographic report presentation consisting of a diagram on which the radiologist draws the coronary arterial anatomy of each individual case is described. The diagram allows a clear visual presentation of all the information gained from the analysis of the original arteriographic study including anatomical variations, the position and importance of each artery in terms of the myocardium it supplies, the sites and severity of obstructions and the presence of collateral pathways. A myocardial scoring system which expresses the severity of left ventricular arterial obstructive disease is also presented. The myocardial score takes into account not only the degree of stenosis of any number of arterial branches, but also their importance in terms of the amount of myocardium supplied.

Angiography↗

PubMed1999

Curvilinear areas in the perinephric fat seen on MR images.

AIM: On magnetic resonance (MR) images, strands correspond to curvilinear areas running in the perinephric fat, and haloes to those lying on the renal surface. Our aim was to examine the diagnostic significance and histopathological basis of these areas. PATIENTS AND METHODS: MR images obtained in 46 patients without renal disease and 96 patients with renal disease were assessed for the signal intensity and extent of strands and haloes, and their degree of right-left asymmetry. RESULTS: Strands usually revealed low signal intensity on T1-weighted MR images and high signal intensity on fat-suppressed T2-weighted images and contrast-enhanced fat-suppressed T1-weighted images. Haloes revealed high signal intensity on fat-suppressed T2-weighted images, but most of haloes were not clearly depicted on T1-weighted images or contrast-enhanced fat-suppressed T1-weighted images. Strands and haloes were common and usually symmetrical or only mildly asymmetrical in both patient groups. However, in 11 of the 96 patients with renal disease, prominent strands and/or haloes appeared with remarkable asymmetry and likely represented definite changes in the perinephric fat. At histopathology, vascular loose fibrous tissue was found at the sites of strands and haloes. CONCLUSION: Strands and haloes usually represent normal anatomical variations. However, the presence of prominent strands or haloes with remarkable right-left asymmetry implies abnormality and may provide additional information in the evaluation of renal disease.

Adipose Tissue↗

PubMed2003

Motor axon migration: a long way to go.

Coordinated motor behaviors rely on a maze-like network of axonal connections between motoneurons and the body musculature. Since the time of the Renaissance, scientists have been fascinated by the question of how such complex, yet stereotypic, connectivity arises during embryogenesis. Here, we review the long journey of motor axons, which traverse diverse territories along predetermined routes riddled with a wealth of divergent pathway options. We conclude that motor axon migration occurs in a stepwise manner, with each step being controlled by local guidance cues, that motor axons rely on some of the same cues that also control axon migration within the CNS, and that, due to species-specific anatomical variations, the cell types providing such local cues may vary. Although studies of motor axon migration have not yet resulted in a complete understanding of the cellular and molecular mechanisms regulating this process, we have come a long way since the days of da Vinci.

Animals↗

PubMed2002

Mechanically induced electrical potentials of articular cartilage.

While there is increasing evidence that chondrocytes are affected by mechanically induced stimuli, endogenous force-related electrical potentials within articular cartilage have been so far observed only in-vitro. Using a porcine ex-vivo model (German Land Race), 8 knee joints were explanted and exposed to mechanical force (up to 800 N) using a special device. Electrodes were inserted into the cartilage matrix. With an amplifier and an A/D transducer the changes of electrical voltage between the electrodes as well as those of the force were recorded online and simultaneously on a computer. Additionally, we located one pair of electrodes on the surface of the cartilage tissue to detect electrical fields outside the cartilage tissue. In relation to the applied force we observed that electrical potentials derived from inside and outside the articular cartilage showed a correspondence. When an alternating force with an amplitude of 360 N and a frequency of about 0.2 Hz was periodically applied, we measured peak amplitudes ranging from 2.1 to 5.5 mV within the cartilage tissue with electrical negativity within the weight bearing area of the cartilage tissue. The measured voltages depended on the applied force, the location of the electrodes, and on anatomical variations. We found an almost linear relation between the magnitude of the applied force and the recorded voltage. With the help of the electrodes located outside and within the cartilage tissue, we were able to show that force dependent fields are generated inside the cartilage. There are several theories explaining the origin of these electrical phenomena, many of them focusing on the negative charges of the proteoglycans in relation to the flow of interstitial fluid and ions under compression. However, the consequences of these phenomena are yet not clear.

Animals↗

PubMed1989

The surgical management of persistent cloaca: results in 54 patients treated with a posterior sagittal approach.

This report describes the author's personal experience in the surgical treatment of 54 patients. The approach is called posterior sagittal ano recto vagino urethroplasty (PSARVUP). Forty patients underwent a primary procedure, and 14 a secondary operation. The anatomic variations found were multiple, integrating a wide spectrum of defects. The posterior sagittal approach proved to be a good initial approach, and permitted complete repair of the defect in 47 patients. Seven patients required a laparotomy in addition. The length of the common channel varied from 0.5 to 7 cm. Common channels longer than 3 cm usually required some technical alternative to replace the vagina. In at least 34 cases, the vagina was reconstructed primarily without any additional technical manoeuvres. Different degrees of vaginal and uterine septation were found in 25 of 50 cases. Hydrocolpos was an associated defect in 14 of 49 patients. Sixty-eight percent of the patients had an important associated urological defect. Twenty-six patients were clinically evaluated without medical management, twenty-one of whom had voluntary bowel movements by the age of 3 years, but most of them had minor episodes of soiling. Nineteen patients had a normal sacrum, and five had urinary incontinence that was successfully managed by intermittent catheterization. Seven patients had a very abnormal sacrum, and five of them had urinary incontinence. Twenty patients underwent a late postoperative vaginoscopy, 14 of whom showed an adequate introitus and vagina, whereas five had different degrees of narrowing of the introitus. Six patients had a urethrovaginal fistula. One ureter was accidentally divided and one vagina had complete ischaemic necrosis.

Adolescent↗

PubMed2006

What are the most powerful determinants of endoscopic vesicoureteral reflux correction? Multivariate analysis of a single institution experience during 6 years.

PURPOSE: As the indications for endoscopic correction of vesicoureteral reflux continue to expand, the emergence of potential predictive variables has been noted. We used univariate and multivariate statistical analyses to find the most significant predictors of correction to improve patient selection. MATERIALS AND METHODS: A consecutive series of patients treated at a single institution was reviewed. Between August 1998 and August 2004, 232 children endoscopically injected with polydimethylsiloxane were identified, representing 351 refluxing units. A total of 23 variables were subjected to statistical analysis to detect predictors of reflux correction after injection. All identified patients with complete data and followup evaluations were included irrespective of anatomical variations, previous interventions or comorbidities. RESULTS: The overall success rate by patient and renal unit was 65% and 72%, respectively. In patients with a single system low grade (1-3) vesicoureteral reflux who did not previously undergo injection this success rate increased to 80%. Univariate analysis demonstrated that higher physician experience, low preoperative vesicoureteral reflux grade, absent renal scars and no previous injections were statistically significant predictors of vesicoureteral reflux correction (p <0.05). A history of febrile urinary tract infections and a duplex system did not attain significance (p = 0.069 and 0.076, respectively). On multivariate statistical evaluation only physician experience, preoperative vesicoureteral reflux grade and the number of previous injections remained significant. CONCLUSIONS: Multivariate analysis of our data showed the most important determinants of vesicoureteral reflux correction after endoscopic injection. Prospective validation will allow us to generate nomograms to better select and counsel patients who would benefit from vesicoureteral reflux treatment.

Child↗

PubMed1993

The transplantation of difficult donor kidneys and recipients: helpful surgical techniques.

Due to the current shortage of organ donors a coalescence of surgical techniques has been applied in an attempt to use all compatible organs that may have been discarded due to anatomical variations, disease or damage, and to transplant them into higher surgical risk recipients. Selected cases have been chosen that illustrate some of these techniques, and the various types of recipients and donor kidneys. Cases 1 and 2 illustrate applications of the orthotopic technique of renal transplantation, as well as reconstructive measures that may be necessary for success. Renal transplantation in perhaps one of the more commonly encountered difficult recipients, the patient with severe atherosclerotic vascular disease, is addressed by cases 1 and 3. The use of unusual donor organs, such as horseshoe kidneys and pediatric donor en block kidneys, is particularly pertinent in the attempt to transplant all viable organs and is demonstrated in cases 4 and 5. These cases illustrate the application of various surgical techniques in which either a difficult recipient or a damaged and/or diseased donor kidney may have otherwise precluded renal transplantation.

Adult↗

PubMed1987

Cephalad renal movement during percutaneous nephrostolithotomy.

The change in the position of the kidney during percutaneous nephrostomy is a major concern to urologists who participate in percutaneous stone removal. We report that the majority of kidneys ascend an average of 2.2 cm. when the patient turns from a supine to a prone position. This change in position is more marked on the right side and is more common in male patients. Knowledge of this anatomical variation is important to determine which patients are suitable candidates for percutaneous nephrostolithotomy and to plan a percutaneous approach to a renal or ureteral calculus.

Adult↗

PubMed1979

Are excretory urograms necessary in evaluating women with urinary tract infection?

Of 164 excretory urograms obtained from women with a history of recurrent urinary tract infections 88 per cent were perfectly normal. Eleven (6.7 per cent) had minor, normal, anatomic variations. Nine (5.5 per cent) were considered to have positive findings but in no case a significant finding present that required surgical intervention or altered the therapeutic approach. The total cost of the studies to the patients involved was $17,930. Thus, an extremely negative cost-benefit ratio emerged. The routine use of excretory urograms as part of the evaluation of a woman with a urinary tract infection is expensive, unrewarding and has little justification.

Cost-Benefit Analysis↗

PubMed1976

Hepatorenal artery bypass in the management of renovascular hypertension.

Infrequently, when the aorta cannot be used for a standard renal bypass operation because of a previous aortic operation, severe degenerative atherosclerosis or complete aortic thrombosis, a unilateral (hepatic) or bilateral (hepatic and splenic) visceral bypass should be contemplated. Patients with abdominal aortic aneurysms extending above the renal arteries might benefit from concomitant bilateral visceral bypass procedures followed by aortic replacement during the same operative session. The hepatic circulation with its common anatomic variations, indications, surgical technique and effects of hepatorenal artery bypass on the renal and hepatic circulation are discussed.

Female↗

PubMed2004

Management of intracranial complications of sinus surgery.

Endoscopic sinus surgery has an impressive and continually im-proving safety record. Increasing surgical experience and improved techniques and equipment make this procedure fundamentally safe. Anatomic variations, extensive disease, and the tight confines that the sinuses occupy between the skull base and orbits, however, do allow the possibility of untoward events. Many of these complications are minor, but the potential for significant morbidity, including blindness, diplopia, cerebrospinal fluid fistula with or without meningitis, intracranial brain injury, and hemorrhage from internal carotid artery injury, is real. This article discusses the avoidance and management of these complications.

Humans↗

PubMed2005

[Transverse radioulnar branch of the dorsal ulnar nerve: anatomic description and arthroscopic implications from 45 cadaveric dissections].

PURPOSE OF THE STUDY: We conducted an anatomic study of the transverse branch of the dorsal ulnar nerve to describe its morphology and position in relation to arthroscopic exploration portals. MATERIAL AND METHODS: Forty-five non-side-matched anatomic specimens of unknown age and gender were preserved in formol. The dorsal branch of the ulnar nerve was identified and dissected proximally to distally in order to reveal the different terminal branches. The morphometric analysis included measurement of the length and diameter of the transverse branch and measurement of wrist width. We also measured the smallest distance between the transverse branch and the ulnar styloid process, and between the branch and usual arthroscopic portals (4-5, 6R, 6U) in the axis of the forearm. RESULTS: The transverse branch was inconstant. It was found in 12 of the 45 dissection specimens (27%). In two-thirds of the specimens, the branch ran over less than 50% of the wrist width, tangentially to the radiocarpal joint. Mean nerve diameter was 1 mm. It was found 5-6 mm from the ulnar styloid process and was distal to it in 83% of the specimens. The dissections demonstrated two anatomic variants. Type A corresponded to a branch running distally to the ulnar styloid process, parallel to the joint line (10/12 specimens). Type B exhibited a trajectory proximal to the ulnar styloid process, crossing the ulnar head (2/12 specimens). The relations with the arthroscopic portals (4-5, 6R, 6U) showed that the mean distance from the branch to the portal was 3.75 mm for the 4-5 portal (distally in 11/12 specimens), 3.68 mm for the 6R portal (distally in 10/12 specimens), and 4.83 mm for the 6U portal (distally in 7 specimens and proximally in 5). DISCUSSION: To our knowledge, there has been only one report specifically devoted to this transverse branch. Two other reports simply mention its existence. According to the literature, the transverse branch of the dorsal ulnar nerve occurs in 60-80% of the cases. We found two anatomic variations different than those described in the literature. Based on our findings and data reported previously, we propose a new classification, describing two main types. In Type 1, the transverse branch arises proximally to the ulnar styloid process;type 1A and type IB are described in relation to the direction of the branch. In Type II, the branch arises distally to the ulnar styloid process;type IIA and type IIB again being described in relation to the direction of the branch. On the tangential trajectory over the radiocarpal joint, the morphometric data show a zone of risk described by a rectangle measuring 10 mm wide (6 mm distal and 4 mm proximal to the ulnar styloid process) and covering 50% of the wrist width. The relations with arthroscopic portals describe a zone of risk corresponding to a 5-7 mm radius circle centered on the portals (4-5, 6R, 6U), which includes 83% of the transverse branches.

Arm↗

PubMed1997

Hepatic vein reconstruction in 152 living-related donor liver transplantation patients.

BACKGROUND: Hepatic vein (HV) reconstruction is crucial in partial liver transplantation in which the inferior vena cava (IVC) is preserved. METHODS: We reviewed the medical records of 152 living-related donor liver transplantations (LRDLTs) in 150 children (45 left lobe grafts, 106 lateral segment grafts, and 1 right lobe graft) monitored for 12 months or longer. RESULTS: A standard technique was a wide end-to-side anastomosis between the donor HV and cuffs, consisting of the recipient middle and left HV and an incision to the IVC. In 15 of 22 partial grafts with two separated HVs the two vessels were reformed by back table surgery to have a common anastomotic orifice, and two separate anastomoses of the individual vessels were made for the remaining seven grafts. Four patients with an absence of infrahepatic IVCs and two with completely obstructed IVCs had end-to-end anastomoses with recipient IVCs. Four patients with stenotic IVCs had end-to-side anastomoses with new orifices on the IVCs. Two patients had acute HV obstruction caused by twisting of the HV that required laparotomy, and six had late-onset HV obstruction that required radiologic intervention. A tissue expander was placed prophylactically in the right subphrenic space in 10 patients to prevent the dislocation of the graft into the right subphrenic space. CONCLUSIONS: It is important in HV reconstruction in partial liver transplantation to make wide orifices and to adapt each graft to its orthotopic place, taking into consideration graft shape, size of the abdominal cavity of the recipient, and anatomic variations in vessels.

Adolescent↗