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At least 793 records · Page 44Linked to original sources
PubMed1994

Laparoscopic sonography. An alternative to routine intraoperative cholangiography?

OBJECTIVE: To determine whether laparoscopic sonography (LS) could be a valid alternative to intraoperative cholangiography (IOC) in the detection of bile duct stones and anatomical variations. DESIGN: Prospective, controlled study comparing LS and IOC using intraoperative findings and/or postoperative endoscopic retrograde cholangiopancreatography as the gold standard. SETTING: Department of Surgery at Zürich University Hospital, Switzerland. PATIENTS: One hundred consecutive patients undergoing laparoscopic cholecystectomy between January 1992 and January 1993. Twenty-three patients were operated on for acute cholecystitis, while the remainder experienced symptomatic bile duct stones. Ninety-six patients underwent preoperative sonography and 85 underwent intravenous cholangiography. Laparoscopic sonography was performed in all patients after dissection of the cystic duct. INTERVENTIONS: A 5.5-MHz sector scanner with a 360 degrees angle and an optimal depth of 1 to 4 cm was used. After LS, IOC was performed with a 4F ureteric catheter and a modern fluoroscope. Patients with bile duct stones were sent for endoscopic retrograde cholangiopancreatography postoperatively or the stones were removed laparoscopically. RESULTS: Unsuspected common duct stones in three patients and several small calculi in the cystic duct in one patient were detected intraoperatively. Sensitivities and specificities for the detection of bile duct calculi were 100% and 98% by LS and 75% and 99% by IOC, respectively. Anatomical variations of the extrahepatic bile ducts were detected by LS in 20 patients and by IOC in 21 patients. Laparoscopic sonography visualized variations of the hepatic arteries in 22 patients. The average time consumption for LS was 5.4 minutes (range, 2 to 12 minutes) and 16.4 minutes for IOC (range, 4 to 37 minutes). CONCLUSIONS: Laparoscopic sonography is a quick and reliable intraoperative diagnostic tool and could replace IOC in laparoscopic cholecystectomy. Additional trials in a larger patient population are needed for a final assessment.

Acute Disease↗
PubMed2001

Ultrasonographic findings of the axillary part of the brachial plexus.

UNLABELLED: In this prospective study we sought to determine anatomic variations of the main brachial plexus nerves in the axilla and upper arm via high-resolution ultrasonography (US) examination. Positions of nerves were studied via US in three sectional levels of the upper arm in 69 healthy volunteers (31 men and 38 women, median age 28 yr). Analysis was done by subdividing the US picture into eight pie-chart sectors and matching sectors for the position of the ulnar, radial, and median nerves. Shortly after the nerves pass the pectoralis minor muscle, they begin to diverge. At the middle level 9%-13%, and at the distal level, 30%-81% of the nerves are not seen together with the artery in the US picture. At the usual level of axillary block approach, we found the ulnar nerve in the posterior medial position in 59% of the volunteers. The other two nerves had two peaks in distribution: the radial nerve in posterior lateral (38%) and anterior lateral (20%) position, and the median nerve in anterior medial (30%) and posterior medial (26%) position. Applying light pressure distally can displace nerves to the side, especially when they are positioned anterior to the axillary artery. We conclude that an axillary block should be attempted as proximal as possible to the axilla. IMPLICATIONS: This prospective ultrasonography study demonstrates significant anatomic variations of the main brachial plexus nerves in the axilla and upper arm, which may increase the difficulty in identifying neural structures. Applying light pressure on the plexus can move nerves to the side, especially when they are positioned anterior to the axillary artery.

Adolescent↗
PubMed1999

Noninvasive localization procedures in ectopic hyperfunctioning parathyroid tumors.

In primary hyperparathyroidism (pHPT), parathyroidectomy is the treatment of choice, but anatomic variations of ectopic glands may cause surgical failure. Reliable preoperative noninvasive localization procedures would have a positive impact on the operative time and increase recovery rate. We retrospectively evaluated 186 patients with pHPT who were studied before successful parathyroidectomy by double tracer scintigraphy (99mTc-pertechnetate+201TI chloride or 99mTc-pertechnetate +99mTc-sestamibi, 160 patients), ultrasonography (148 patients) and computerized tomography (CT) scan (92 patients). During bilateral neck exploration, 159 (85.5%) single adenomas, 6 (3.2%) parathyroid carcinomas, and 3 (1.6%) double adenomas were found. Moreover, 18 (9.7%) patients had diffuse chief cells parathyroid hyperplasia. Removed parathyroid glands were in ectopic sites in 41 (22.0%) cases, mainly localized in the upper mediastinum or behind the esophagus. The overall sensitivity was 83.5 and 85.2% for 99mTc-pertechnetate+201TI chloride and 99mTc-pertechnetate+99mTc-sestamibi scintigraphy respectively, 80.4% for CT scan and 81.1% for ultrasonography. In patients with ectopic glands, sensitivity was 81.2, 79.5, 73.3 and 81.6% respectively. In 36 out of 41 patients with ectopic glands in whom the removed parathyroids were correctly localized, mean operative time was 95 min, and in 5 patients without preoperative localization it was 260 min. In conclusion, in pHPT, preoperative localization of an enlarged parathyroid is helpful, especially in ectopic adenomas and in anatomic variations in location, and it has been proved to reduce operative time and morbidity rate.

Adenoma↗
PubMed2004

The varying distribution of intra- and inter-vertebral height ratios determines the prevalence of vertebral fractures.

Credible inferences regarding the burden of vertebral fractures (VFs) cannot be made without a globally accepted quantitative definition of 'fracture'. Currently, differences in anterior, middle, or posterior vertebral heights (VHs) within a vertebra, or between adjacent vertebrae, are used to define 'fracture'. However, VH differences are essential for the construction of thoracolumbar curves, evolutionary adaptations that provide stability in bipedal stance and gait. As there is no reference standard to distinguish anatomical variation from fracture, approaches to defining a VF use a reference range of VH ratios derived in premenopausal women or derived by trimming, a method that iteratively removes the tails of a distribution of VH ratios to produce a normal distribution. From this, reference ranges of VH ratio means and standard deviations (SDs) are obtained and a nominal deviation of 15% or more, or 3 SD or more is regarded as a 'fracture'. We measured VHs by quantitative vertebral morphometry (QVM) and bone mineral density (BMD) by dual energy X-ray absorptiometry in 697 Lebanese women (age 20-89 years) to compare the prevalence of VF ascertained by published methods and a new method that uses the premenopausal range (without trimming) and requires two VH abnormalities. VF prevalence using published methods reached 60% to 70% in pre- and post-menopausal women, and in women with normal or high BMD because VH ratios were not normally distributed and cut-offs used to define VF fracture fell within the observed distribution of the data. The new method resulted in a VF prevalence of 3.3% in younger and 14% in older women, 7% (high), 10% (middle), and 20% (low) BMD tertiles consistent with the notion that the method detected VF due to bone fragility. We suggest that using a fixed trimming method to define reference range and cut-offs or applying fixed cut-offs to identify VFs in populations, where these ratios are not normally distributed, may result in the capture of anatomical variation, not structural failure. Thus, group differences in the VF prevalence may reflect differences in methodology, not bone fragility. Improved criteria to define VF are needed before credible inferences can be made regarding the burden of VFs in women and men, and between sexes, races, countries, decades, and placebo arms of clinical trials.

Absorptiometry, Photon↗
PubMed2006

Variability in conduction of the lateral femoral cutaneous nerve.

The purpose of this study was to establish a reliable technique for assessing conduction in the lateral femoral cutaneous nerve (LFCN), bearing in mind its anatomical variation. Based on our anatomical study, normative values were obtained in 40 healthy nerves. The optimal stimulation site was located 1 cm or more media 16470526 l to the anterior superior iliac spine (ASIS) in 93% of cases and over the ASIS in 7%. Sensory nerve action potentials (SNAPs) were recorded simultaneously along an imaginary line between the ASIS and the lateral border of the patella and 2 cm medial to this line. Side-to-side variability in amplitude was 31% for the recording from the line and 30% for the medial recording. The variability significantly decreased to 16% when the higher value of each side was compared. Therefore, the measurement of higher amplitude recorded at two different sites may minimize interside variability and improve the diagnostic utility of the LFCN conduction study.

Action Potentials↗
PubMed2004

Intersection syndrome: MR imaging with anatomic comparison of the distal forearm.

OBJECTIVE: To correlate the anatomic and MR imaging characteristics of the area of intersection of the first and the second dorsal extensor tendon compartments (DETC) in the distal forearm in an attempt to improve the design of MR imaging protocols used for the evaluation of intersection syndrome. DESIGN AND PATIENTS: Ten forearms of nine cadavers underwent MR imaging in the axial and sagittal-oblique planes before and after tenography with direct injection of a gadolinium-containing contrast agent into the first DETC in four forearms, the second DETC in four forearms, and both compartments in the remaining two forearms. The area of intersection between the first and second DETC was identified in each case as well as its distance from Lister's tubercle. Subsequently all forearms were sectioned in the axial (8 forearms) or sagittal-oblique planes (2 remaining forearms) to parallel the imaging planes. Detailed examination of each of the anatomic slices was performed in a search for anatomic variations and for possible anatomic connections of the tendons sheaths. One forearm was dissected to identify the area of intersection. RESULTS: The area of intersection between the first and second DETC occurred between 3.5 cm and 4.8 cm (mean 4.18 cm) proximal to Lister's tubercle. After tenography, gadolinium solution was noted in the third DETC in two of four specimens in which the second DETC was injected and in one of two specimens in which both the first and second DETC were injected. Extension of the gadolinium solution between the first and second DETC was noted during isolated injections of either compartment, although this finding may have related to iatrogenic injection effects. The axial plane was the most valuable for assessment of the area of intersection of the first and second DETC. CONCLUSION: MR imaging is a noninvasive method that can be used for the evaluation of distal forearm and wrist pain. Standard wrist protocols do not include the area of intersection between the first and second DETC and, in those cases in which intersection syndrome is suspected, the MR examination must be tailored to include the forearm.

Aged↗
PubMed2000

Anatomical aspects of sinus floor elevations.

Inadequate bone height in the lateral part of the maxilla forms a contra-indication for implant surgery. This condition can be treated with an internal augmentation of the maxillary sinus floor. This sinus floor elevation, formerly called sinus lifting, consists of a surgical procedure in which a top hinge door in the lateral maxillary sinus wall is prepared and internally rotated to a horizontal position. The new elevated sinus floor, together with the inner maxillary mucosa, will create a space that can be filled with graft material. Sinus lift procedures depend greatly on fragile structures and anatomical variations. The variety of anatomical modalities in shape of the inner aspect of the maxillary sinus defines the surgical approach. Conditions such as sinus floor convolutions, sinus septum, transient mucosa swelling and narrow sinus may form a (usually relative) contra-indication for sinus floor elevation. Absolute contra-indications are maxillary sinus diseases (tumors) and destructive former sinus surgery (like the Caldwell-Luc operation). The lateral sinus wall is usually a thin bone plate, which is easily penetrated with rotating or sharp instruments. The fragile Schneiderian membrane plays an important role for the containment of the bonegraft. The surgical procedure of preparing the trap door and luxating it, together with the preparation of the sinus mucosa, may cause a mucosa tear. Usually, when these perforations are not too large, they will fold together when turning the trap door inward and upward, or they can be glued with a fibrin sealant, or they can be covered with a resorbable membrane. If the perforation is too large, a cortico-spongious block graft can be considered. However, in most cases the sinus floor elevation will be deleted. Perforations may also occur due to irregularities in the sinus floor or even due to immediate contact of sinus mucosa with oral mucosa. Obstruction of the antro-nasal foramen is, due to its high location, not a likely complication, nor is the occurrence of severe haemorrhages since the trap door is in the periphery of the supplying vessels. Apart from these two aspects, a number of anatomical considerations are described in connection with sinus floor elevation.

Bone Transplantation↗
PubMed1991

Anatomy of the gonadal veins: a reappraisal.

Variations in anatomy were found quite frequently during bilateral gonadal vein dissection and resection for pelvic varices in the past 5 years (120 cases). In about one fourth of the cases, routine gonadal phlebography was not technically feasible or did not correlate exactly with the operative findings. Some cases of male varicocele showed recurrence after surgery. These facts, in addition to the scarce information provided by anatomy textbooks, induced us to study thoroughly the gonadal veins. One hundred cadaver dissections (200 veins) were done for length, diameter, number, and location of valves and collaterals, number of trunks in each side, and mode of termination in the renal vein and vena cava. Topographic division of the veins by thirds facilitated the information. Variations from the classic anatomic description were encountered frequently. As to the number of trunks, at the middle third, where the vein is usually divided, only 60% have one trunk on the left and only 75% have one on the right side. The rest are multiple; as many as four and six trunks in the lower third were found. The knowledge of these anatomic variations, not clearly described before, is of great importance to both surgeons and invasive radiologists and conducive to successful results.

Adolescent↗
PubMed1980

In vivo transepidermal water loss and epidermal occlusive hydration in newborn infants: anatomical region variation.

Transepidermal water loss (TEWL) was measured from the abdomen, buttock, and central forearm in 13 term infants by employing an electrolytic water analyzer (Meeco). The hydration level (HL) at these sites following one hour of occlusion and the resulting post-occlusion TEWL were measured. No apparent difference in TEWL was found between regional sites. The forearm and buttock HL appeared similar, while the abdomen values tended to differ considerably from both. Post-occlusion TEWL appeared significantly higher than normal TEWL. Since the buttock and forearm TEWL reflected similarly structured stratum corneum, future studies on the more accessible forarm may be extended by application to the buttock.

Abdomen↗