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PubMed2004

Surgical anatomy of the bile ducts at the hepatic hilum as applied to living donor liver transplantation.

OBJECTIVE: To evaluate anatomic variations of the biliary tree as applied to living donor liver transplantation. SUMMARY BACKGROUND DATA: Anatomic variability is the rule rather than the exception in liver surgery. However, few studies have focused on the anatomic variations of the biliary tree in living donor liver transplantation in relation to biliary reconstruction. METHODS: From November 1992 to June 2002, 165 patients underwent major hepatectomy with extrahepatic bile duct resection; right-sided hepatectomy in 110 patients and left-sided hepatectomy in 55. Confluence patterns of the intrahepatic bile ducts at the hepatic hilum in the surgical specimens were studied. RESULTS: Confluence patterns of the right intrahepatic bile ducts were classified into 7 types. The right hepatic duct was absent in 4 of the 7 types and in 29 (26%) of the 110 livers. Confluence patterns of the left intrahepatic bile ducts were classified into 4 types. The left hepatic duct was absent in 1 of the 4 types and in 1 (2%) of the 55 livers. CONCLUSIONS: In harvesting the right liver from a donor without a right hepatic duct, 2 or more bile duct stumps will be present in the plane of transection in the graft in 3 patterns based on their relation to the portal vein. Accurate knowledge of the variations in the hepatic confluence is essential for successful living donor liver transplantation.

Bile Ducts↗

PubMed2003

Hepatic arteries in potential donors for living related liver transplantation: evaluation with multi-detector row CT angiography.

PURPOSE: To assess the accuracy of multi-detector row computed tomographic (CT) angiography in the evaluation of hepatic arterial anatomy in living related liver transplantation (LRLT) donors. MATERIALS AND METHODS: During a 10-month period, 62 potential LRLT donors were evaluated with CT and conventional angiography. Multi-detector row CT was performed after intravenous injection of 150 mL of contrast material at 3 mL/sec. CT angiograms of the hepatic arteries were generated by a radiologist who used volume rendering and maximum intensity projection techniques without knowledge of results of conventional angiography. Two reviewers reviewed CT and conventional angiograms retrospectively in consensus. The results of the two examinations were then compared. RESULTS: CT examinations were technically adequate in 56 (90%) donors. Respiratory motion artifact compromised detailed hepatic artery analysis in six donors (10%). Second-order branches of right hepatic arteries were visualized in 58 donors (94%), and second-order branches of left hepatic arteries were visualized in 51 (82%). A total of 27 hepatic arterial anatomic variations were detected in 22 donors at conventional angiography. CT angiography accurately depicted 25 (93%) anatomic variations in 20 donors (91%). CT angiography did not depict an accessory right hepatic artery in two donors. The number and origins of dominant arteries supplying segment IV were accurately identified at CT angiography in 51 donors (82%). Hepatic arterial anatomy depicted at CT angiography was identical to that at conventional angiography in 50 donors (81%). CONCLUSION: Multi-detector row CT angiography is useful but limited in its ability to depict the dominant artery supplying segment IV and small accessory hepatic arteries.

Adolescent↗

PubMed2000

A new approach to the classification of maxillary sinus hypoplasia with relevant clinical implications.

The purpose of this study was to discover the prevalence of maxillary sinus hypoplasia (MSH) and associated malformations. A total of 490 consecutive axial and coronal computerized tomographic (CT) scans of the paranasal sinuses were obtained from patients with chronic sinusitis. CT scans were assessed for the presence of MSH and associated anatomic variations. A new classification of MSH was made, and the diagnostic criteria listed. The frequency of anatomic variations coexisting with MSH was also estimated. MSH was encountered in 21 (4.2%) of the 490 patients. Unilateral types I, II and III MSH were seen in 7 (1.4%), 6 (1.2%) and 8 (1.6%) respectively. MSH was bilateral only in 3 (0.6%) patients, one of which was a bilateral type II. In the remaining two bilateral MSH cases, there was a type II MSH on one side and type III MSH on the other in each patient. Middle conchal pneumatization was the most common coexisting anatomic anomaly in MSH, followed by agger nasi cell, secondary middle concha, paradoxical middle concha and superior conchal pneumatization. A patient with MSH should be carefully evaluated prior to any sinus surgery in order to avoid surgical complications. With precise CT assessments, an MSH can be diagnosed and distinguished from other maxillary sinus anomalies. With the additional criterion of orbital enlargement, and the help of reproducible measurement techniques explained in this study, an objective diagnosis and classification can be made in further investigations of MSH.

Adolescent↗

PubMedDate not supplied

Surgical anatomy of the external branch of the superior laryngeal nerve.

Iatrogenic lesions of the external branch of the superior laryngeal nerve (EBSLN) during thyroidectomies are not infrequent due to the possibility of anatomic variations of the relationships of this nerve with the superior thyroid vessels. Therefore, based on an anatomic analysis of 30 superior thyroid poles from 15 fresh cadavers, a new classification of the EBSLN was proposed, considering the jeopardy during a thyroidectomy. Thirty-seven percent of the nerves were type 2, ie, crossing the superior thyroid pedicle less than 1 cm above the superior thyroid pole. It is notable that 20% were type 2b, ie, crossing the vessels below the upper border of the pole, having been considered "high risk." This incidence was comparable with other series, which found dangerous anatomic variations of the EBSLN in the range of 15% to 68%, confirming that a significant proportion of these nerves might be at risk during surgery on the superior thyroid pole.

Adult↗

PubMed2002

Healing results of prolonged acute frontal sinusitis treated with endoscopic sinus surgery.

In a marked part of patients suffering from acute frontal sinusitis, the symptoms do not resolve after initial therapy (antibiotics and/or trephination). The prolongation of the healing or recurrences may be caused by persistent inflammation or by structural abnormalities at the nasofrontal connection. During the last decade endoscopic surgery (FES) has become a very useful method to restore the frontonasal drainage although long term results of this kind of population are rare. We evaluated the results of endoscopic surgery in two patient groups (total number of 50) both operated after prolongation (persistent symptoms after 4 weeks) of the initial acute phase of the frontal sinusitis. The first group (A, 15 patients, first trephined) was followed-up 4 years, the number of recurrences after the first FES was 60% and in the other group (B, no initial trephination) with over 6 months follow-up, 91% of patients had recurrences. In group A pre- and postoperative CT-scanning was used to determine the possible anatomical variations that could be causing the failures. All but 3 patients showed some kind of abnormal anatomical variation. In group B only preoperative CT was done. In most cases the reasons for recurrences of frontal sinusitis were polyps and/or chronic inflammation at the ethmoidal region.

Acute Disease↗

PubMed1998

Posterior interosseous flap and its variations for coverage of hand wounds.

BACKGROUND: Conventional posterior interosseous flap has the disadvantage of partial or even complete necrosis of the flap when there is anatomical variation or contusion around its distal pedicle. To make it a more reliable flap, three types of auxiliary procedures were designed. METHODS: (1) When there is congestion after inset of the distally based flap, an additional venous anastomosis was carried out. (2) When there is anatomical variation so that a distally based flap could not be raised without compromising the nerve branches, or when contusion was found around the distal pedicle, the flap was changed into a free flap. This design is also indicated for coverage of the distal fingers. (3) When the patient is elderly with possible peripheral arterial disease, the flap was raised with a wide base, incorporating the branches of both the anterior and posterior interosseous arteries. There were eight, 36, and five patients in each group, respectively. RESULTS: There was only one failure in the free flap group. No partial necrosis of the flap was found. Other complications were analyzed. CONCLUSION: With these backup procedures, the posterior interosseous flap can be more widely used with safety. By combining various reconstructive armaments, the result of a conventional procedure can be improved.

Adolescent↗

PubMed2004

Quadricuspid aortic valve: report of three cases.

Quadricuspid aortic valve (QAV) is a very rare congenital malformation. We have encountered three patients with QAV, of whom one patient may be the eldest reported patient with this particular anatomical abnormality. In another of our patients, there was aortic regurgitation, aortic stenosis, and healed infective endocarditis, with adhesion of the tips of the cusps. In all three patients, the cusps were all of equal size. Until now, there has been very little documented evidence about the anatomical variations in QAV or its relationship with infective endocarditis. From the available literature, we conclude that the anatomical variations in patients with QAV are similar to those in patients with quadricuspid pulmonary valve, and infective endocarditis may not be an uncommon complication.

Aged↗

PubMed1998

Variation of anatomic valve area during ejection in patients with valvular aortic stenosis evaluated by two-dimensional echocardiographic planimetry: comparison with traditional Doppler data.

OBJECTIVES: Flow variations can affect valve-area calculation in aortic stenosis and lead to inaccuracies in the evaluation of the stenosis. Knowing that transvalvular flow varies normally within one beat, we designed this study to assess the response of the valve to intrabeat variation of flow during systole. Results were compared with flow-derived measurements. BACKGROUND: Technological improvements now allow us to evaluate aortic valve area directly by short axis planimetry. This offers the possibility to perform serial planimetries during one ejection phase and analyze the intrabeat dynamic behavior of the stenotic-aortic valve and compare these measurements with flow-derived measurements. METHODS: Forty echocardiograms displaying different degrees of aortic stenosis were analyzed by frame-by-frame planimetry of the valve area from onset of opening to complete closure. Maximal-mean area, opening and closing rates and ejection times were obtained and compared with Doppler-derived data. RESULTS: Valve area varied during ejection. Stenotic valves opened and closed more slowly than normals and remained maximally open for a shorter period. Mean area by Doppler data corresponded more closely to maximal than to mean-planimetered area. Duration of flow was shorter than valve opening in severely stenotic valves. Discrepancies between Doppler-derived and two-dimensional (2D) measurements decreased in less stenotic valves. CONCLUSIONS: Our observations reveal striking differences between the dynamics of normal and stenotic valves. Surprisingly, Doppler-derived mean-valve area correlated better with maximal-anatomic area than with mean-anatomic area in patients with aortic stenosis. Discrepancies between duration of flow and valve opening could explain this phenomenon.

Aged↗

PubMed2006

Loose bodies in a sublabral recess: diagnosis and treatment.

A case of a 26-year-old male with symptoms resulting from loose bodies residing in a sublabral recess is presented. Operative intervention using the standard arthroscopic portals in addition to an accessory posterior portal was successful in removing the loose bodies and approximating the edges of the sublabral foramen. The shoulder is a complex region made up of numerous anatomic structures, which if damaged may be responsible for a patient's pathology. Normal anatomic variations also exist, which in certain situations, may contribute to a patient's presentation. One example of a normal anatomic variation is the sublabral foramen, which represents an unattached anterosuperior labrum.

Adult↗

PubMed2001

Extra-articular origin of biceps brachii.

We report a clinically relevant anatomic variation of the tendon of the long head of biceps brachii muscle. The clinical and historically relevant data regarding an anatomic finding observed in 1 patient are reviewed. The clinical outcome of the patient's care was successful. Recognition of the described anatomic variant of the biceps tendon can aid the surgeon in focusing the treatment on the actual pathology and not on aberrant anatomy. Several anatomic variations in the origin of the long head of the biceps brachii have been observed. Some of these anomalies have been implicated as having a role in rotator cuff tendinopathy or in exposure for shoulder surgery. We are reporting the observation that the long head of the biceps tendon may have a mesotendon or be incorporated in the extra-articular side of the glenohumeral joint capsule, making arthroscopic visualization and assessment of the tendon difficult.

Adolescent↗

PubMed1998

Sinonasal anatomy.

Recent advances in paranasal sinus imaging have been driven by the development of functional endoscopic sinus surgery. The goal of most sinus imaging is to provide a surgical road map delineating the anatomy, defining the obstructing lesions, and noting anatomic variations that may predispose to operative complications. We review the embryology and development of the nose and paranasal sinuses; review the radiographic anatomy of the adult sinuses and their drainage pathways; and point out variations in the normal anatomic pattern, concentrating on those variations that are significant for the functional endoscopic sinus surgeon.

Humans↗

PubMed2005

The arch of the great saphenous vein: anatomical bases for failures and recurrences after surgical treatment of varices in the pelvic limb. About 54 dissections.

The arch of the great saphenous vein presents numerous tributaries. Misappreciation of their anatomical variations might cause recurrence after surgical treatment of varices. We dissected 54 inguino-femoral regions of fresh, black African corpses. Our purpose was to study the anatomical variations in the vein confluents of the arch of the great saphenous vein; its positions in relation to the external pudendal artery; establish palpable anatomical markers for its surgical approach. The conventional type in a 'vein star' shape was not the most frequent. Upper or abdominal common vein produced through the merging of superficial veins of the anterior abdominal wall and genital or internal common vein were more frequent. An anterior saphenous vein was found in 23 cases. The external pudendal artery crossed beneath the arch of the great saphenous vein cross in 56% of cases and previously in 44% of cases. On average, the top of the arch of the great saphenous vein was projected out 10.88 cm from the ventral and cranial iliac spine, 3.83 cm from the pubic tubercle and 4.19 cm from the inguinal ligament. In view of our results, variations are real. Knowing and taking them into account are essential to prevent recurrences after surgical treatment of varices of the pelvic limb.

Cadaver↗

PubMed2003

Surgical anatomy of the extralaryngeal aspect of the superior laryngeal nerve.

OBJECTIVES: To describe the topography of the superior laryngeal nerve (SLN) and to evaluate the influence of gender, ethnicity, side of the neck, and individual height on the topography of the SLN. DESIGN: Anatomical study of human cadavers. SUBJECTS: Fifty fresh human cadavers (19 female subjects and 31 male subjects; age range, 22-89 years; mean age, 61 years) were randomly selected for this study. The subjects were divided into nonwhite (n = 18) and white (n = 32) ethnic groups. The t test and linear regression were used for statistical analysis of data. RESULTS: All SLNs emerged medially to the vagus nerve. The SLNs mostly divided into internal (ibSLN) and external (ebSLN) branches distally from their origin (94%). The mean +/- SE length of the SLN trunk was 16.7 +/- 0.9 mm and was affected by gender (P =.01) but not ethnicity (P =.57), side of the neck (P =.96), or individual height (R2 = 0.01; P =.33). The length of the ibSLN reached 44.9 +/- 1.0 mm and was unaffected by gender (P =.91), ethnicity (P =.24), side (P =.40), or height (R2<0.01; P =.71). The length of the ebSLN measured 62.6 +/- 1.2 mm and was unaffected by gender (P =.69), ethnicity (P =.42), side (P =.26), or height (R2<0.01; P =.85). The mean +/- SE angle between the ibSLN and the tracheoesophageal sulcus was 49 degrees +/- 1 degrees and was unaffected by gender (P =.35), ethnicity (P =.11), side (P =.26), or height (R2<0.01; P =.96). Only 1 subject demonstrated a bilateral anatomical variation of the ibSLN close to its entrance into the thyrohyoid membrane. CONCLUSIONS: The topography of the SLN has a few anatomical variations and is unaffected by gender, ethnicity, side of the neck, and individual height, except that the SLN is longer in males than in females. These findings are important in that they can help in the prevention of SLN injuries during operations such as laryngectomy and neck dissection, as well as in the planning of laryngeal reinnervation and transplantation.

Adult↗

PubMed2006

Hepatocellular carcinoma: transcatheter arterial chemoembolization of the gonadal artery.

Over the past 9 years, the authors have identified gonadal arteries supplying hepatocellular carcinoma in seven of 4,438 patients (0.16%) whom they attempted to treat by transcatheter arterial chemoembolization. All seven patients had tumors in the Couinaud segment 6 (S6) of the liver (mean size, 6.8 cm). The gonadal arteries in all seven patients showed anatomic variations, including a high origin (n = 3) and a common trunk with the adrenal artery (n = 4). The gonadal artery with anatomic variation may supply hepatocellular carcinomas located in liver S6.

Adult↗

PubMed2002

[Surgical anatomy of the liver: what you need to know].

A precise knowledge of arterial, portal, hepatic and biliary anatomical variations is mandatory when a liver surgery is planned. However, only certain variations must be searched when a precise intervention is planned. The main liver resection and biliary interventions will be precised. Related anatomical variations will be precised.

Cholecystectomy↗

PubMed1997

Statistical methods in computational anatomy.

This paper reviews recent developments by the Washington/Brown groups for the study of anatomical shape in the emerging new discipline of computational anatomy. Parametric representations of anatomical variation for computational anatomy are reviewed, restricted to the assumption of small deformations. The generation of covariance operators for probabilistic measures of anatomical variation on coordinatized submanifolds is formulated as an empirical procedure. Populations of brains are mapped to common coordinate systems, from which template coordinate systems are constructed which are closest to the population of anatomies in a minimum distance sense. Variation of several one-, two- and three-dimensional manifolds, i.e. sulci, surfaces and brain volumes are examined via Gaussian measures with mean and covariances estimated directly from maps of templates to targets. Methods are presented for estimating the covariances of vector fields from a family of empirically generated maps, posed as generalized spectrum estimation indexed over the submanifolds. Covariance estimation is made parametric, analogous to autoregressive modelling, by introducing small deformation linear operators for constraining the spectrum of the fields.

Algorithms↗

PubMed1989

Surgical significance of persistent cholecystohepatic ducts.

Anatomical variations of the biliary tract occur frequently enough so as to worry the general surgeon dealing with this problem. Generally speaking, these anatomical variations are not identified prior to surgery. Anomalous drainage of the common hepatic duct into the gall bladder was identified while performing a cholecystectomy. The common bile duct proximal to the cystic duct was atretic. The problem described above was successfully managed by hepatico-jejunostomy.

Adolescent↗

PubMed2003

Persistent left superior vena cava: a reason for pseudodisplacement of a port catheter.

Port catheters have been increasingly used in recent years. Using one case as an example, we demonstrate how an anatomic variation can easily become a pitfall when inserting a central venous catheter, port catheter, pacemaker or Swan-Ganz catheter. We report a case of persistent left superior vena cava, the most common variation in the thoracic venous system. Since these procedures are increasingly being performed, surgeons, anesthesiologists and radiologists should be aware of the possible anatomic variations.

Catheterization, Central Venous↗