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PubMed2004

Endoscopic and surgical management of bile duct injury after laparoscopic cholecystectomy.

Laparoscopic cholecystectomy has become the first choice of management for symptomatic cholecystolithiasis. While it is associated with decreased postoperative morbidity and mortality, bile duct injuries are reported to be more severe and more common (0-2.7%), when compared to open cholecystectomy (0.2-0.5%) [New Engl. J. Med. 234 (1991) 1073; Am. J. Surg. 165 (1993) 9; Surg. Clin. N Am. 80 (2000) 1127]. These bile duct injuries include leaks, strictures, transection and removal of (part of) the duct, with or without vascular damage. Bile duct injury might be due to misidentification of the biliary tract anatomy due to acute cholecystitis, large impacted stones, short cystic duct, anatomical variations, but also due to technical errors leading to bleeding with subsequent clipping and coagulation trauma [Ann. Surg. 237 (2003) 460]. Early recognition and adequate multidisciplinary approach is the cornerstone for the optimal final outcome. Suboptimal management of injuries often leads to more extensive damage to the biliary tree and its vasculature with as consequences biliary peritonitis, sepsis, abscesses, multiple organ failure, a more difficult (proximal) reconstruction and in the long run, secondary biliary cirrhosis, and liver failure. Despite increasing experience in performing laparoscopic cholecystectomy, the frequency of bile duct injuries has not decreased [Ann. Surg. 234 (2001) 549]. Therapy encompasses endoscopic stenting, percutaneous transhepatic dilatation (PTCD) and surgical reconstruction.

Bile Ducts↗

PubMed2004

A quantitative morphometric study of the human anterior cingulate cortex.

Morphometric alterations in the anterior cingulate cortex (ACC) have been reported in schizophrenia and mood disorders. Parameters affected include glial and neuronal density, neuronal size and cortical thickness. Some data, especially in mood disorders, suggest that the left subgenual ACC is preferentially involved. Qualitative studies show that the ACC cytoarchitecture is heterogeneous, but there are few quantitative data. We performed a quantitative morphometric study of five anatomical levels within the ACC (caudal and rostral subgenual [area 24b sg], rostral and intermediate supragenual [area 24b] and caudal supragenual [area 24b']) in both hemispheres of five normal brains. We measured cortical depth, layer depths, neuronal density, neuronal size, and glial density, using the optical disector and nucleator. Relative to the subgenual ACC, the supragenual ACC was thicker, with a deeper layer V. Supragenual neurons were substantially larger in all layers, and were less densely packed in layers V and VI, than subgenual neurons. Glial density, and the glia to neuron ratio, was higher in supragenual than subgenual ACC. Only minor differences were seen between left and right ACC, between caudal and rostral subgenual ACC, and between the three supragenual levels. These data complement the qualitative descriptions of the heterogeneity of human ACC cytoarchitecture, connections, and functions, especially between supragenual and subgenual regions. Our findings also indicate that care must be taken when selecting ACC tissue to be used for morphometric studies of psychiatric disorders, since the normal anatomical variation is of a similar magnitude as the reported disease-related alterations.

Adult↗

PubMed2004

Cardiac pacing systems and implantable cardiac defibrillators (ICDs): a radiological perspective of equipment, anatomy and complications.

Cardiac pacing is a proven and effective treatment in the management of many cardiac arrhythmias. Implantable cardiac defibrillators (ICDs) are beneficial for certain patient groups with a history of serious, recurrent ventricular dysrhythmias, with a high risk of sudden cardiac death. Pacemaker devices take many forms and are highly visible on the chest radiograph. The radiographic appearances of ICDs and pacemakers can be similar and are subject to similar complications. The anatomical approach to the implantation, the type of device used and anatomical variations will all affect the appearance of these devices on the chest film. Pacemaker complications identified radiographically include pneumothorax, lead malpositioning, lead displacement or fracture, fracture of outer conductor coil, loose connection between the lead and pacemaker connector block, lack of redundant loops in paediatric patients and excessive manipulation of the device by the patient (Twiddler's syndrome). This pictorial review highlights the role of chest radiography in the diagnosis of post-cardiac pacing and ICD insertion complications, as well as demonstrating the normal appearances of the most frequently implanted devices.

Arrhythmias, Cardiac↗

PubMed2004

Transesophageal echocardiography to guide pulmonary vein mapping and ablation for atrial fibrillation.

BACKGROUND: This study describes the use and outcomes of transesophageal echocardiography to guide atrial fibrillation (AF) ablation procedures. METHODS: Under general anesthesia, 25 patients with a history of AF underwent multiplane transesophageal echocardiography in conjunction with catheter placement under fluoroscopy. RESULTS: In this series, a combined fluoroscopic/echocardiographic approach obviated the need for angiographic imaging. Anatomic variation in pulmonary veins (PV) was common; the shortest distance between the ostia ranged from 2 to 11 mm. Individual PV diameters did not predict the presence of ectopic foci. The number of radiofrequency pulses delivered per vein was 2.6 +/- 2.3 (range: 0-10). Mean fluoroscopy time per procedure was 31 +/- 13 minutes and mean procedure time was 110 +/- 31 minutes. At follow-up, 68% of patients were free from AF. CONCLUSIONS: Transesophageal echocardiography enables identification and cannulation of the ostia and proximal branches of PV during AF ablation. Fluoroscopy, procedure times, and outcomes compare favorably with series using PV angiography and, as such, suggest that a controlled trial is warranted.

Adult↗

PubMed2006

Venous variants and anomalies on routine abdominal multi-detector row CT.

OBJECTIVE: This study aims to determine the types and prevalence rates of anatomic variations of the hepatic veins, portal vein, inferior vena cava and renal veins, and to establish statistical correlations between various anomalies and frequency differences between male and female using multi-detector row computed tomography (CT). MATERIALS AND METHODS: One thousand one hundred and twenty patients (588 men, 532 women) were evaluated with routine abdominal CT. Frequencies of different variants were noted and compared, and correlations between three categories of variation were tested. RESULTS: In total, 1261 abdominal vein variants and anomalies were identified in 756 (67.5%) of 1120 patients. Six hundred and forty-two hepatic vein variants were detected in 468 (41.8%) patients. One or more inferior right hepatic veins were identified in 356 (31.8%) individuals, and tributary hepatic veins were detected in 147 (13.1%) patients. Portal vein variations and anomalies were observed in 307 (27.4%) cases. The most frequent of these was trifurcation (139 patients, 12.4%). A total of 311 inferior vena cava and renal vein variants were identified in 258 (23%) cases. Six patients (0.5%) exhibited inferior vena cava anomalies, 62 (5.5%) had circumaortic renal veins, 53 (4.7%) had retroaortic renal veins, and 210 (18.8%) had multiple renal veins. CONCLUSION: The prevalence of abdominal vein variations is high, and routine abdominal CT demonstrates these abnormalities very well. The data suggest that hepatic vein variants and multiple right renal veins are more frequent in women than in men, and that hepatic vein variation is correlated with portal vein variation.

Abdomen↗

PubMed2005

Mechanics of the subtalar joint and its function during walking.

Knowledge of the location of the subtalar joint axis in individual patients would permit clinical assessment of the forces and moments that produce frontal-plane foot and ankle deformities. Biomechanical analysis of the subtalar joint is hindered, however, by the inaccessibility of the talus, which makes locating the joint axis difficult, and by the high degree of intersubject anatomic variation. This article discusses work done with cadaver specimens and using invasive methods in vivo that has enhanced our understanding of the mechanics of the subtalar joint and its function during gait. Also reviewed are investigations of the actions of muscles that cross the subtalar joint.

Biomechanical Phenomena↗

PubMedDate not supplied

Transverse colon herniation through the foramen of Winslow presenting with unusual CT findings.

Bowel herniation through the foramen of Winslow is among the rarest of internal hernias, accounting for less than 0.8%. In its origin, a pivotal role is played by some anatomic variations, or anomalies such as the increased mobility of the right transverse colon, and maybe the exceedingly large bore of the foramen itself. The first case of hernia through the foramen of Winslow was reported by Blandin in 1834. Since then, no more that 200 new cases have been described. Diagnosis usually is established during surgery while treating a bowel obstruction. Only in an exceedingly small group of patients is diagnosis achieved preoperatively on the basis of radiological findings. We describe a preoperatively diagnosed case of transverse colon herniation through the foramen of Winslow, showing a portal vein narrowing and periportal lymphedema at computed tomography (CT). To the best of our knowledge, only a few cases of preoperative CT diagnosis of Winslow foramen hernia have been described in the past. None had the above-mentioned CT findings.

Colon, Transverse↗

PubMed2006

Sigmoid volvulus an update.

Sigmoid volvulus is the third most common cause of colonic obstruction in the United States after cancer and diverticulitis. Etiologic factors include anatomic variation, chronic constipation, neurologic disease, and megacolon. Management of sigmoid volvulus involves relief of obstruction and the prevention of recurrent attacks; the outcome depends on the population and selection of patients. Although volvulus is uncommon, it may be encountered during pregnancy and is a condition that poses significant risk to both mother and fetus requiring a management strategy that varies with each trimester.

Decompression, Surgical↗

PubMed2006

Idiopathic avascular necrosis of the scaphoid: Preiser's disease.

Preiser's disease, or idiopathic avascular necrosis of the scaphoid, is a rare, albeit often debilitating, condition. Although unknown, the etiology is probably multifactorial, with biomechanical or anatomical variations leading to an "at risk" scaphoid. Most commonly the diagnosis is made with the use of plain radiographs, but one should not hesitate to use MRI for both confirming the diagnosis and evaluating the stage of the disease. Current treatment algorithms are not standardized, and many scaphoids degenerate to a point that a salvage procedure is required. The authors attempt a revascularization procedure if the disease is caught early and the scaphoid has not yet gone on to collapse and degenerate. We save our salvage procedures for advanced cases with periscaphoid arthritis.

Humans↗

PubMed2004

False positive computed tomography findings in aortic dissection.

Dissection is the commonest acute catastrophe involving the aorta. Computed tomography (CT) is increasingly used in evaluating patients with suspected aortic dissection. Occasionally normal anatomic structures may be misconstrued as pathologic due of lack of familiarity with anatomical variations. In scanning two patients with suspected dissection, we encountered pitfalls that led to an erroneous diagnosis of dissection. The subsequent clinical course and evaluation confirmed that the CT findings were artefactual. This report illustrates these potential errors and discusses the mechanisms.

Journal Article↗

PubMed2005

A novel reporting approach to coronary angiography: "segmental coding system".

BACKGROUND: A new systematic reporting system for coronary angiography has been developed, which is capable of describing any visible intraluminal or extraluminal conditions with the exact coordinates. METHODS: In this method, called "segmental coding system"(SCS), the part of the artery that is located between its two subsequent branches is considered to be an "angiographic segment". Conditions are localized according to their relationship with these angiographic segments and the anatomic border of the segments (coronary ostiums, primary, secondary and tertiary branches, grafts and proximal and distal anastomosis sites). They are also described by using a special coding system that consists of letters, numbers and signs. SCS can supply the name (stenosis, occlusion, contour deformity, aneurysm, rupture, anatomical variation, existence of stent, etc.) and the exact localization (coordinates) of the condition with its properties; filling direction, and the collateral system that fills the vessel. RESULTS: We applied SCS to more than 500 cineangiograpies. According to our experience, SCS provides more objective, detailed, and even correct information than the current narrative reporting system. SCS also offers many extra advantages. (a) It can describe all imaginable types of lesion combinations. (b) All of the existing conditions can be listed without missing. (c) The definitions are very precise and clear. They can easily be understood by everyone in the same way. (d) It is more advantageous on archiving, searching the database, and comparing the subsequent reports for the same patient. (e) In the future, by using specially tailored software, personal and detailed angiographic images will be reproduced from the SCS data. CONCLUSIONS: By being introduced into clinical practice, we believe, SCS will prove a very useful tool for both surgeons and cardiologists.

Coronary Angiography↗

PubMed2005

Anomalous left anterior descending, absent circumflex and unusual dominant course of right coronary artery: a case report--R1.

A 40-years-old female presented with atypical chest pain. Selective coronary angiography revealed separate osteal origin of anomalous left anterior descending (LAD) and normal origin of right coronary artery (RCA) from right anterior coronary sinus. LAD had a septal course. Left circumflex (LCx) was absent. RCA, a dominant vessel, continued beyond the crux, along the entire length of atrioventricular groove as circumflex artery. There was no myocardial ischemia on stress thallium. As per our knowledge, this type of combination of anatomical variation of coronary circulation has not been described in the literature.

Adult↗

PubMed2004

A population-based atlas and clinical target volume for the head-and-neck lymph nodes.

PURPOSE: To develop a population-based three-dimensional lymph node target volume of the head and neck. METHODS AND MATERIALS: The T2 weighted axial magnetic resonance imaging (MRI) images of 35 patients with known head and neck cancer were reviewed. An experienced head and neck radiologist marked each lymph node (LN) electronically. The images were distributed to one of 12 axial levels of the head and neck with each level representing a distinct portion of the neck based on external contours and the presence of anatomic structures. The LNs were marked with five different symbols to distinguish the superior/inferior extent of each LN within each level. With the categorization of each image into a different superior/inferior level of the neck, the registration of the images was limited to two dimensions. Nonlinear transformation accounted for inter-patient differences although no local warping was used. The co-registration used recognizable anatomic landmarks (vertebral body, mandible, maxilla, clivus as well as the sternocleidomastoid muscle, external skin contour, spinal cord) to match the patient anatomy. RESULTS: In total, 503 images were co-registered with the baseline images. The majority of the co-registrations were of good quality; 361, 122, and 20 image co-registrations scored as global, limited, and poor co-registrations respectively. One thousand and fifty seven LNs were marked, with 122 LNs marked as submandibular and submental LN. Among the levels A, B, C, D, E, F, G, H, 22, 44, 206, 199, 196, 175, 63, 35 LN were marked respectively. Noteworthy anatomic variation was observed among the different nodal groups that are summarized in the representative baseline images. CONCLUSIONS: Image registration of a series of head and neck images generates a valuable population-based lymph node map that can be used to guide the three-dimensional delineation of the elective lymph node target volume. Significant variation in the lymph node location was seen in all LN groups. The medial border of the internal jugular vein can be used as an important landmark structure in delineating the jugular LN clinical target volume and, for that reason, intravenous contrast is recommended to improve visualization. The location of the submandibular LN appear to be limited to the space anterior and lateral to the submandibular gland and are found mostly along the inferior edge of the mandible. The location of the retropharyngeal LN does vary but their location does not appear to vary with any other recognizable axial structure. The lymph node map provides another collaborating piece of evidence in defining the head and neck LN clinical target volume.

Adolescent↗

PubMed2006

Dose-modeling study to compare external beam techniques from protocol NSABP B-39/RTOG 0413 for patients with highly unfavorable cardiac anatomy.

PURPOSE: The aim of this study was to select patients with heart anatomy that is specifically unfavorable for tangential irradiation in whole-breast radiotherapy (WBRT), to be used as an experimental cohort to compare cardiac dosimetric and radiobiological parameters of three-dimensional conformal external beam accelerated partial breast irradiation (3D-CRT APBI) to WBRT with techniques as defined by the National Surgical Adjuvant Breast and Bowel Project (NSABP) B-39/Radiation Therapy Oncology Group (RTOG) 0413 clinical trial. METHODS AND MATERIALS: A dosimetric modeling study that compared WBRT and 3D-CRT APBI was performed on CT planning data from 8 patients with left-sided breast cancer. Highly unfavorable cardiac anatomy was defined by the measured contact of the myocardium with the anterior chest wall in the axial and para-sagittal planes. Treatment plans of WBRT and 3D-CRT APBI were generated for each patient in accordance with NSABP B-39/RTOG 0413 protocol. Dose-volume relationships of the heart, including the V5min (minimum dose delivered to 5% of the cardiac volume), biological effective dose (BED) of the V5min, and normal tissue complication probability (NTCP) were analyzed and compared. RESULTS: Despite expected anatomic variation, significantly large differences were found favoring 3D-CRT APBI in cumulative dose-volume histograms (p < 0.01), dose to the entire heart (mean difference 3.85 Gy, p < 0.01), NTCP (median difference, 1.00 Gy; p < 0.01), V5min (mean difference, 24.53 Gy; p < 0.01), and proportional reduction in radiobiological effect on the V5min (85%, p < 0.01). CONCLUSIONS: Use of 3D-CRT APBI can demonstrate improved sparing of the heart in select patients with highly unfavorable cardiac anatomy for WBRT, and may result in reduced risk of cardiac morbidity and mortality.

Breast Neoplasms↗

PubMed2003

Brachial plexus injury following subclavian vein catheterization: a case report.

Subclavian vein cannulation may be complicated by lesions of the peripheral nervous system, such as injury to the recurrent laryngeal nerve, phrenic nerve, and brachial plexus. We describe a case of lesion of the upper trunk of the brachial plexus during multiple attempts at subclavian vein catheterization. This type of complication, ascribed to erroneous application of procedures or anatomical variations, may be minimized by abstaining from multiple attempts at venipuncture.

Brachial Plexus↗

PubMed2006

Variant location of the musculocutaneous nerve during axillary nerve block.

We present the case of a 56-year-old man who underwent axillary nerve block for a wrist arthroscopy procedure, with real-time ultrasound and peripheral nerve stimulator guidance. The ulnar nerve and radial nerve were located medial and posterior to the brachial artery, respectively. A large complex structure was noted in the position typically occupied by the median nerve. Contact of this structure with the stimulating needle produced strong biceps contraction, and slight adjustment of the needle resulted in forearm pronation. After injection of 10 mL of local anesthetic near this structure, it appeared to consist of two separate components on ultrasound. We believe that these components represented the median and musculocutaneous nerves lying together, lateral to the artery. Radial, median, ulnar, and musculocutaneous nerve block ensued, and wrist arthroscopy was carried out uneventfully. Knowledge of this anatomical variation may improve anesthesiologists' ability to provide effective axillary block.

Arthroscopy↗

PubMed2006

Cyanoacrylate adhesive for closing sinus membrane perforations during sinus lifts.

INTRODUCTION: Sinus lift procedures depend greatly on fragile structures and anatomical variations. The procedure may cause sinus membrane perforations, which can lead to graft infection and early failure. AIM: To assess the efficacy of cyanoacrylate adhesive in the management of large perforations of the maxillary sinus membrane during sinus lifts. MATERIAL AND METHODS: Six rabbits were used in the study. Sinus membrane perforations (about 1.5 cm in length) were repaired with cyanoacrylate adhesive on one side of the maxillary sinus. On the contralateral side, an identical laceration was not repaired. Histological evaluation was performed 2 weeks after the operation. RESULTS: Wounds repaired with cyanoacrylate adhesive showed newly formed continuous epithelium across the previous perforation site and there was sinusitis on the contralateral side. CONCLUSION: These results support the clinical use of cyanoacrylate adhesive for repairing sinus membrane perforations.

Animals↗

PubMed2005

Wrist denervation and the anterior interosseous nerve: anatomic considerations.

PURPOSE: Wrist denervation via resection of the distal anterior interosseous nerve (AIN) and the posterior interosseous nerve (PIN) is an effective treatment for chronic wrist pain. When performing this procedure through a dorsal approach we have been impressed by anatomic variations of the AIN. This has raised concerns about potential denervation of the pronator quadratus (PQ). The purpose of this study was to elucidate the anatomy of the AIN and PIN as encountered through a dorsal distal forearm incision. METHODS: Ten fresh-frozen cadavers were dissected. Before dissection radiographs were obtained to ensure accurate localization of the proximal ulnar head with a radiopaque marker. A dorsal approach to the distal forearm was made to identify the anatomy of the PIN and AIN. The location and diameter of all AIN branches were noted by using an operating stereoscopic microscope at x 25 magnification and a precision caliper. The PIN anatomy and size also were noted. RESULTS: The anatomy of the AIN was variable. The average AIN diameter proximal to the PQ was 1.5 mm. The average number of AIN motor branches was 4.2. The largest PQ motor branch was the first motor branch and was located at an average distance of 37.9 mm from the proximal ulnar head. The last motor branch was found an average of 23.9 mm from the proximal ulnar head. In 9 of 10 specimens the sensory branch tunneled radially through the distal PQ and innervated the periosteum of the volar distal radius. In 4 of 10 specimens a separate branch to the distal radioulnar joint was present. We found an average PIN diameter of 0.87 mm. CONCLUSIONS: Resection of the AIN at a point 4 cm proximal to the proximal point of the ulnar head would denervate completely the PQ in our cadaver population. Division of the AIN 2 cm proximal to the ulnar head would spare most of the PQ motor branches.

Aged↗