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PubMed1992

[Measurements and variations in the region of the optic canal. CT and anatomy].

This investigation of the optic canal is based on measurements of 60 macerated adult European skulls from the Alexander-Ecker Collection at the Anatomy Department of the University of Freiburg. An indian skull is also described, in which the cranial end of the left optic canal is closed by a bony plate. Computer tomographical and anatomical measurements were compared in order to assess the correlation of the two methods of investigation and the accuracy of the CT representation of osseous structures. The coronal projection of the optic canal proved to be optimal for CT examination--the sections meet the optic canal at an angle of 85.5 degrees. The measurements of transverse diameters correlate poorly, whereas vertical diameters and distances correlate well. The extent to which anatomical variations can be assessed by CT was also investigated. All anatomical variants could be observed in coronal sections, except the bony lamina in the Indian skull, which could not be seen until a contrast medium was used. The so-called "keyhole anomaly" appeared in 3.3% in our material, the "figure-of-eight" variant in 2.5%, and a carotid clinoid canal in 13.3%.

Adult↗

PubMed1992

Non-invasive assessment of the Circle of Willis using transcranial pulsed Doppler ultrasound with angiographic correlation.

The ability of transcranial pulsed Doppler ultrasound (TCD) to provide a dynamic assessment of the functional capability of the Circle of Willis was assessed using conventional cerebral angiography for anatomic correlation. Eleven patients had normal four-vessel cerebral angiography prior to being investigated with ultrasound. Angiography and ultrasound both demonstrated a functional anterior communicating artery in nine of the eleven patients, giving complete agreement between the two techniques. Posterior communicating arteries were visualized angiographically in all eleven patients. Ultrasound identified bilateral functional vessels in nine, the other two patients having non-functional vessels. In these latter two patients, angiography demonstrated three of the four posterior communicating arteries to be hypoplastic and it was uncertain whether these vessels carried significant blood flow. The fourth posterior communicating artery was shown to have an absent proximal segment of the ipsilateral posterior cerebral artery, with a persistent fetal posterior communicating artery. This anatomical variation is a potential limitation of ultrasound for assessing functional posterior communicating arteries. These preliminary results indicate that a combination of the anatomical (angiographic) and dynamic (ultrasonic) data may prove to be complementary for assessing the Circle of Willis.

Adult↗

PubMed2001

Magnetic resonance imaging of the wrist ligaments.

The advent of small arthroscopes has enabled the hand surgeon to visualize the ligaments of the wrist directly with resultant increased accuracy in diagnosing and treating pathology. Orthopaedists are now demanding a preoperative assessment and this, in turn, has necessitated that radiologists have a comprehensive understanding of wrist anatomy. High resolution MR imaging can identify the wrist ligaments reliably and provide information concerning their integrity. Interpretation is not straightforward; there is considerable anatomic variation, and there are perforations, defects and degenerative tears that can be troublesome in diagnosing injury. However, with experience and attention to anatomic detail, the radiologist can provide useful information regarding structural abnormalities. When injured, the ligaments of the wrist behave as other joint ligaments do. Findings following injury include discontinuity of normal striated bands, incomplete disruption, irregularities and alteration in normal signal. Fluid pooling around a ligament and concomitant bone injury are other clues to injury. The identification of such structural abnormalities may help to explain altered biomechanics and improve the management of patients following wrist injury.

Humans↗

PubMed1989

Basic concepts of femoral neck anteversion: comparison of two definitions.

Femoral neck anteversion is determined by the neck, shaft and knee axes. It is commonly assumed that the neck axis is a straight line connecting the centre of the femoral head, the centre of the femoral neck and the axis of the femoral shaft. However, the line through the centre of the femoral head and neck crosses anterior to the axis of the femoral shaft. A distinction has therefore to be made between two principal different definitions of anteversion, denoted ANTEV 1 and ANTEV 2 in this paper, depending on the precise definition of the neck axis. Previous studies have indicated substantial differences between these definitions. The present study, using precise measuring methods, shows that the definitions have a systematic but small spread of differences. The large individual variation previously found between the two definitions is therefore caused mainly by the measuring methods and to a lesser extent by real anatomical variations.

Adult↗

PubMed1997

The meniscofemoral ligaments of the knee.

The meniscofemoral ligaments (MFL) of the knee have both functional and clinical importance, but have been poorly described. We examined 42 human cadaver knees: there was at least one MFL in every joint and both ligaments were present in 27. The anterior MFL was present in the knees in all 18 males and in 17 of the 24 females. The posterior MFL was present in 16 males and 22 females. Measurement of the ligaments showed that they were of significant size. The mean midpoint width for the anterior MFL was 5.09 +/- 1.41 mm in males and 2.99 +/- 1.29 mm in females. The mean width of the posterior MFL was 5.48 +/- 2.13 mm in males and 3.79 +/- 2.56 mm in females. The average length of the anterior MFL was 27.09 +/- 2.15 mm in males and 24.38 +/- 3.39 mm in females, and the posterior MFL was 31.13 +/- 2.54 mm and 27.59 +/- 3.74 mm, respectively. There were anatomical variations in 16 (38%) knees (62.5% female, 37.5% male), more commonly in the posterior ligament. We conclude that the meniscofemoral ligaments are anatomically and probably functionally important structures in the human knee.

Cadaver↗

PubMed2002

Operative management of skull base malignancies: choosing the appropriate approach.

Malignant tumors of the skull base are complex lesions. Identifying the indications and contraindications for resection is essential for the successful treatment of these lesions. This requires an understanding of the pathology, principles of resection, and nonsurgical therapeutic modalities. Choosing the appropriate surgical approach requires an understanding of the tumor and its association with the anatomy of the skull base. Preoperative assessment and preparation of the patient for the postoperative course, including functional and cosmetic deficits, are reviewed in the context of the specific approach. Anatomical variations encountered in the preoperative planning are discussed. A review of reconstructive alternatives is presented that is specific to the approach and anatomical violation. Finally, the use of a multidisciplinary team both in and out of the operating room is recommended, emphasizing a team approach during the resection itself.

Cerebrovascular Circulation↗

PubMed2002

[Preservation of the recurrent laryngeal nerve].

A strategy to protect the inferior laryngeal nerve (ILN, recurrent and non-recurrent) as well as the superior laryngeal nerve (SLN) includes the reason for and extend of the operation to avoid recurrent goiter, selection of an experienced institution and operating team, a cautious intubation, adequate and anatomical operating technique, recognition of risk factors and postoperative treatment with a sufficient dosage of hormone and/or iodine. The ILN should be dissected routinely in view of its anatomical variation. The "capsular dissection technique" should be applied. The "laterialisation technique" of the upper pole protects the SLN with regard to its anatomic variability. Neuromonitoring of both nerves can be helpful under difficult circumstances.

Humans↗

PubMedDate not supplied

Right gastric artery embolization prior to treatment with yttrium-90 microspheres.

PURPOSE: Intra-arterial infusion of yttrium-90 microspheres is a form of radiation treatment for unresectable hepatic neoplasms. Misdeposition of particles in the gastroduodenal area such as the right gastric artery (RGA) may occur with serious consequences. We present a series of patients who underwent a detailed vascular study followed by RGA embolization. Special emphasis is placed on anatomic variations and technical considerations. METHODS: In a 1 year period, 27 patients were treated. Initial vascular evaluation was performed, with careful attention to anatomic variants or extrahepatic arterial supply, especially to the gastroduodenal area. Embolization of such arteries was planned if needed. RGA embolization was performed antegradely from the hepatic artery or retrogradely via the left gastric artery (LGA). Postprocedural follow-up included clinical interview and gastroscopy if necessary. RESULTS: RGA embolization was performed in 9 patients presenting with primary (n = 3) or metastatic liver tumors (n = 6). Six patients underwent antegrade RGA embolization and 3 had embolization done retrogradely via the LGA. Retrograde access was chosen for anatomic reasons. None of the patients complained of gastroduodenal symptoms. CONCLUSION: RGA embolization can help minimize the gastroduodenal deposition of radioactive particles. RGA embolization should routinely be carried out. The procedure can be performed, with similar technical success, by both anterograde and retrograde approaches.

Antineoplastic Agents↗

PubMed1999

Morphometrical examinations of the mandibular ramus for the indication of lag screw osteosynthesis described by Eckelt in mandibular condylar fractures.

For several years, lag screw osteosynthesis as described by ECKELT has been used for the surgical treatment of condylar fractures with predominantly positive results. However anatomical variations occasionally do not permit the use of the lag screw. The aim of the present study was to re-examine the anatomical requirements for using ECKELT's lag screw osteosynthesis. Based on a detailed structural analysis of 140 isolated cadaver rami mandibulae, it can be seen that they principally meet the anatomical requirements for the treatment of mandibular condylar fractures with lag screw osteosynthesis using 2.0 mm diameter screws. Rare, extreme anatomical variants emphasize the need for a stricter preoperative determination of the indications. Using spiral computerized tomography, it is possible to exactly assess preoperatively the existing anatomical situation of the ascending mandibular ramus on the planned frontal plane of the lag screw.

Bone Screws↗

PubMed2003

The free deltoid flap: microscopic anatomy studies and clinical application to oral cavity reconstruction.

The deltoid free flap is a fasciocutaneous flap that should be thin, hairless, of an adequate size, and capable of sensory reinnervation. Because of its excellent color-matching and texture-matching characteristics, it has recently been widely used for the reconstruction of soft-tissue defects during oral and maxillofacial surgery. Furthermore, a characteristic of oral and maxillofacial soft-tissue defects is that they are not large; therefore, flap size will be small, allowing the donor site to be directly closed. Because of natural variation in parts of the anatomy, there has sometimes been great difficulty in clinical application. The authors decided to study this by performing anatomical studies of the deltoid region on 21 cadavers. The result indicates that the pedicle of the deltoid free flap penetrates the "quadrangular space" in 90 percent of cases but passes and does not penetrate the quadrangular space in the remaining cases. The authors also confirmed that the skin has a vascular network comprising five layers and, furthermore, that the vascular network of the deep fascia is dense. The authors also report six cases of its clinical use complicated by anatomic variation and local infection in which the deltoid flap showed a completely successful outcome.

Aged↗

PubMed2004

Innervation of the coracobrachialis muscle by a branch from the lateral root of the median nerve.

Anomalies of the brachial plexus have previously been described in the literature. The coracobrachialis muscle is typically innervated by the musculocutaneous nerve. During a gross anatomy dissection we found that the coracobrachialis muscle was innervated by a branch from the lateral root of the median nerve. Knowledge of the anatomical variations of the peripheral nervous system is important in interpreting unusual clinical presentations. This report will assist clinicians and surgeons by pointing out anatomical anomalies associated with the musculocutaneous nerve, the median nerve and their branches to the anterior compartment muscles of the upper arm.

Dissection↗

PubMed2003

Splenodiaphragmatic interposition of the descending colon.

We present a variation named splenodiaphragmatic or retrosplenic interposition of the colon in three patients aged 6, 70, and 71 years who suffered from different symptoms. The cases were found in 1,000 thoracoabdominal CT scans examined at the radiology clinic between 1999 and 2001. The upper part of descending colon was seen to be between the spleen and the left kidney on abdominal CT scans with contrast enema in the patient aged 71 years. In a 6 year-old child, part of the left colic flexure in the intestinal gas patterns was located between the left kidney and spleen, extending up to the diaphragm in the left hypochondrium on radiological examinations. The left colic flexure and the beginning of the descending colon were imaged on CT behind the spleen at the level of the 11th thoracic vertebra in the third patient aged 70 years. Hepatodiaphragmatic interposition of the colon has been reported previously in many patients; however, no detailed reports are available dealing with the interposition of the descending colon between the diaphragm and spleen. Three cases with retrosplenic colon variation were investigated in detail in the present study. The significance of retrosplenic colon is discussed. It is concluded that the identification of this anatomical variation could avoid unnecessary colon perforation during percutaneous nephrostomy, splenostomy, biopsy, or splenectomy.

Aged↗

PubMed2000

[Anatomy of the valve system of the internal jugular vein].

BACKGROUND: Central venous catheters (CVC) in the internal jugular vein have become an important adjunct to the overall management of intensive care patients, but their use is associated with frequent neck complications. In a review of the literature anatomical variation in size, form and function of the valve system of the internal vein was found. PURPOSE: This study macroscopically and microscopically investigates the anatomical variety of the vein valves of the inferior internal jugular vein. MATERIAL AND METHODS: 100 cadavers from legal autopsies were investigated. We selected 45 patients with an acute myocardial infarction death and a control group (55 patients) formed by different causes of death. The veins were prepared for light microscopic study, the specimens were serially sectioned (ca. 30 sections) and stained with hematoxylin and eosin. RESULTS: Anatomical variety was observed predominantly unilateral on the right side of the internal jugular vein. The valves were often bicuspid at the right side (92%) and tricuspid on the left side (64%) and mostly located ca. 2 cm above the subclavia-jugularis bifurcation. In the histological study, a variability of the net of collagen and elastin fibres in the tunica intima and media was observed. The structure of the adventitia was constant. 18 patients with a jugular valve vein incompetence (age over 60) appeared to have thickening of the tuberculum in the sinus of the valve. The cups of the valves were found rudimentary in these patients with advanced stages of tricuspid incompetence. CONCLUSION: The present study demonstrates the variety of the valves of the jugular vein. They play an important role to impede the retrograde flow during cardiopulmonary resuscitation as well as in jugular vein cannulation.

Adolescent↗

PubMed1990

Pelvic anatomy relative to lumbosacral instrumentation.

Anatomical study of 72 pelves revealed that the most substantial area of bone that could best support a rod for surgical fixation is the body of the ilium, with the best part of the bone being the area above the sciatic notch. Placement of the rods into the body of the ilium provides good fixation but requires complex bending of the rods and a good three-dimensional perception of the osseous anatomy of the pelvis. This study was undertaken to define the intraosseous anatomy and the range of anatomical variation of the ilium. The results of this study are useful in developing a prebent spinal fixation rod, providing a better understanding of this anatomical area from a three-dimensional perspective and providing better lumbosacral spinal instrumentation.

Anthropometry↗

PubMed1993

[Reoperations in parathyroid surgery].

In a continuous series of 439 parathyroidectomies for primary or secondary hyperparathyroidism, 36 cases were reoperations. The initial operation had been a prior parathyroid exploration (PTx) in 17 cases, a thyroidectomy (Tx) in 17 cases, both operations in two cases. The incidence of parathyroid glands discovered at exploration was lower in both types of reoperations (67% after Tx, 72% after PTx) than in patients who were explored for the first time (94%). Anatomical variations and parathyroid pathologies were comparable in patients reoperated after Tx and in those explored for the first time. In patients reoperated after PTx, anatomical abnormalities (46% of glands in ectopic locations, 12% of supernumeray glands) and multiglandular pathologies (56% of hyperplasias) were much more frequently encountered. Long term results were satisfactory in patients explored for the first time (98% cures) and in reoperations after Tx (94% cures), but were less favourable in reoperations after PTx (78% cures).

Adult↗

PubMed1994

Absence of symmetry in superior articular facets on the first cervical vertebra in humans: implications for diagnosis and treatment.

OBJECTIVE: Little attention has been given to the craniovertebral articulations. Specifically, gross observations of variations of the superior articular facets on the atlas have not been described with respect to static and motion palpation findings. This study describes the anatomical variations of these facets and the clinical implications associated with asymmetrical structure. DESIGN: The superior articular facets of thirty human first cervical vertebrae were chosen for this study because the atlas constitutes the middle of the upper cervical complex and the atlanto-occipital joint contributes greatly to head movements. SETTING: The basic science research department of Logan College of Chiropractic, St. Louis, Missouri. SPECIMEN POPULATION: All available previously dissected anatomy laboratory and library specimens (30) were used in this study. All of the specimens were dry with intact facet surfaces and no regard was given to age, gender, or race. INTERVENTIONS: The atlases were studied out of situ and all soft tissue was removed so that the bony articular surfaces could be clearly viewed and photographed. MAIN OUTCOME MEASURES: Palpation and unaided visual examination were performed on 30 atlases. The shape, size, angle, texture, border, and number of superior articular facets on each atlas were recorded to determine symmetry. RESULTS: The classically described kidney-shaped facet was in fact an infrequent finding. Upon comparison of right and left sides, none (0%) of the facets were mirror images of symmetry, while 19 of the atlases (63%) had grossly asymmetrical facets, and 11 of 30 atlases (37%) had facets which were only slightly asymmetrical in regard to shape, border, depth and angle. Furthermore, 7 of the 19 grossly asymmetrical atlases (37%) had three or four separate superior articular facets. Three atlases had two facets on the left and one on the right, while two atlases had two facets on the right with a single facet on the left, and two atlases had four superior facets (two on each side). CONCLUSION: The validity of vertebral joint assessment based on the assumption of facet symmetry is challenged, impugning certain chiropractic theories and/or techniques which rely on symmetry as being "normal." To achieve symmetrical function, the anatomical structure must be symmetrical. Since true structural symmetry does not exist, true symmetry of segmental movement may not be possible.

Atlanto-Axial Joint↗

PubMed1982

The mechanism of transient myopia induced by sulfonamide therapy.

We performed acute and convalescent A-scan echographic ocular measurements documenting the anterior chamber depth, lens thickness, and axial length of a patient with acute transient sulfamethoxazole-induced myopia. Shallowing of the anterior chamber, independent of changes in the thickness of the lens, was the only anatomic variation found that could explain the myopia. Swelling of the ciliary body, with forward movement of the lens-iris diaphragm, could produce this transient anatomic change.

Adult↗

PubMed2002

[Blood supply of the lips].

An important study of lips arterial supply was enabled using multiple sources of information: anatomical dissection, cadaver and "in vivo" arteriography and phlebography. Literature was a great help, especially a recent analysis of lips microvascularisation done by H. Sick. The classical figure of labial circular artery was found out to be quite seldom, whereas an important number of anatomical variations where shown. Also there was a total independence between inferior and superior lip venous drainage, for embryological reasons. Finally lymph drainage was studied by anatomical dissection with the use of Gerota mass and the G. Hidden's work. It appeared that cutaneous and mucosal drainage were separate, since the nodes were different. All these information have been useful and confirmed during more than a thousand surgical procedures performed in our maxillo-facial surgery unit of Besançon medical school.

Arteries↗