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PubMed1998

Sonographically guided placement of peripherally inserted central venous catheters: review of 355 procedures.

OBJECTIVE: This paper reviews our experience using sonographic guidance in the insertion of peripherally inserted central venous catheters (PICCs). SUBJECTS AND METHODS: Three hundred fifty-five PICCs were placed in 262 patients, 19-92 years old, over a 24-month period using sonographic guidance for the initial venous cannulation. RESULTS: The average number of punctures was 1.2, with an average procedure time of 21 min. Our overall success rate to achieve the initial venous access was 99%. I.v. contrast material was used in only 2% of the cases, after successful initial venous access with sonographic guidance alone, to allow demonstration of anatomic variations or lesions that interfered with the completion of the procedure. Two immediate minor complications occurred. A high margin of safety was provided by avoiding the use of iodinated contrast medium and by visualizing the artery and its anatomic relation to the vein before and during needle placement. CONCLUSION: Sonographic guidance yielded superior three-dimensional localization of the selected vein and its precise anatomic relationship to the artery. Our experience has led us to conclude that sonographically guided placement of PICCs is a fast, safe, efficient, and inexpensive technique and should be the preferred method for PICC placement, especially in patients with no clinically identifiable peripheral vein.

Adult↗

PubMed2003

Microscopic anatomy of the infraorbital canal, nerve, and foramen.

OBJECTIVE: We performed this study to investigate the morphologic and topographic anatomy, and variations of the infraorbital canal (IOC), infraorbital nerve (ION), and infraorbital foramen (IOF). STUDY DESIGN AND SETTING: This study was performed at the Anatomy Department of Ankara University School of Medicine between 1999 and 2000. The morphometry of these anatomic areas on cadaver heads were studied microscopically. The morphologic and topograpic anatomies of IOC, ION, and IOF were carried out microscopically with x 25 to x 40 magnification on 10 cadaver heads (20 sides). RESULTS: We found the shape of the IOF as oval in 30% (6 sides), round in 40% (8 sides), and semilunar in 30% (6 sides) of the cadaver heads. We detected the IOF as single in 90% (18 sides), double in 5% (1 side), and triple in 5% (1 side) of the cases. We determined a complete roof (we called it as "canal") in 50% of cases and groove plus canal in 50% of the heads. The mediolateral relationship of the vessels to the nerve while emerging from the IOF was investigated, and the artery was always found in a mediosuperior position and the vein was inferior to it. In all specimens, the ION was found to be consisting of 3 to 8 fascicles interwoven with the artery and the vein in the loose connective tissue sheath. CONCLUSION: A detailed knowledge of the anatomic morphometry of this area is necessary for a surgeon while performing maxillofacial surgery and regional block anesthesia. Anatomic variations on this area may take place and a surgeon must take this into consideration so as to increase the surgical success.

Female↗

PubMed2001

Morphometric study of the human lumbar spine for operation-workspace specifications.

STUDY DESIGN: The anatomy of the lumbar vertebrae of 55 patients was measured by use of data provided by computed tomography. On the basis of these measurements, the location of puncture points and the orientation of the surgical instruments for pedicle, vertebral body, and disc entry points were calculated for open as well as percutaneous surgery. OBJECTIVE: Normal anatomic variations of the lumbar spine were investigated to define the workspace for several spinal procedures and to define the workspace of a robot designed to guide the physician during those procedures. SUMMARY OF BACKGROUND: Several comprehensive studies of vertebrae dimensions have been conducted in the past, but they lack several dimensions that are needed to determine the exact location of the entry point and orientation of the tool, in particular when a computerized guidance system is used. METHODS: Fifty-five spinal columns (L1-L5, total 250 vertebrae) were measured by computed tomography. These data provide geometric relations that determine entry points and tool orientations for different spinal interventions. RESULTS: The workspace for spinal operations was defined on the basis of anatomic data taken from computed tomography scans. The data included 15 measurements for each vertebra that defined its shape. The processed data provided puncture points for several spinal procedures in both open and percutaneous surgery. CONCLUSIONS: This study provides additional information on vertebral structure needed to calculate accurately the entry point and tool orientation in various spinal procedures. These statistical data are also valuable for model and implant designs and for workspace specifications for a robot-assisted surgery system.

Adult↗

PubMed2005

Rare variations of the left subclavian artery.

The subclavian artery is a major constituent of the blood circulatory system. Its position in the root of the neck and its course through the interscalene triangle are significant. Its branches supply divers areas in the body from the brain to the thorax. This case report describes an unusual range of anatomical variations of the course of the left subclavian artery, the origin, and absence of some of its branches and the concomitant abnormal course of the phrenic nerve. Clinical syndromes related to certain variations are reviewed.

Aged↗

PubMed1988

[Can skin texture serve as a guide in the course and variation of the median nerve?].

Human palms and soles are textured with skin different to that of the other body surface. Instead of sebaceous glands or hairs, there are sweat glands opening into the epidermal ridges. This is only common in primates. For a long time, a connection between dermatoglyphics and medical disorders has been known, but anatomic investigations are rare. In this study, the relationship between anatomic variations of the median nerve and dermatoglyphic patterns is explored.

Carpal Tunnel Syndrome↗

PubMed1999

Loading technique comparison in permanent 125I prostate implants.

Treatment of prostate cancer utilizing iodine 125 (125I) interstitial seed implants has become an accepted and widely used modality. Numerous variations in 125I seed implant loading distribution techniques have developed as a result of the preferences of individual institutions implementing the modality. No particular universal standard is currently used for 1251 seed implants. A major concern with 125I seed implants is coverage of the prostate with the desired dose and the minimization of dose to the urethra. A variation of seed distribution per individual anatomy is desirable. Historically, brachytherapy relied on dosimetry systems, such as the Paris, Quimby, and Manchester systems to achieve the desired dose distribution. Use of various peripherally loaded 125I seed implant distributions to accommodate anatomic variations within the same institution prompted the interest of how the results compare to the Manchester system.

Brachytherapy↗

PubMed2001

Ultrasound diagnosis and Doppler monitoring of a pelvic spleen in pregnancy.

We describe a patient with a pelvic spleen diagnosed during pregnancy and monitored through gestation which we believe to be the first reported case. A 40-year-old woman was referred at 8 weeks of gestation because of a chronic intense pain in the left iliac cavity which had spread to her lower back. Clinical examination revealed a poorly defined pelvic mass. Pelvic ultrasound demonstrated a gestational sac containing a viable embryo whose size was consistent with the period of amenorrhea. While the splenic area in the left hypocondrium was found to be empty, a homogeneous and elongate mass measuring 152 x 123 mm with a maximum thickness of 53.4 mm was observed in the left iliac cavity above the uterus. This mass, the ectopic spleen, was monitored by Doppler velocimetry at monthly intervals until delivery and no variation throughout gestation was observed; therefore, despite the occasional occurrence of heavy pain, it was possible to exclude circulatory complications such as thrombosis or torsion. Doppler ultrasound proved to be a useful tool for the differential diagnosis of this rare anatomical variation.

Adult↗

PubMed1998

Diagnostic imaging in pediatric trauma.

In the head and neck, the futility of skull radiography is again reemphasized as a poorer predictor of intracranial injury than is a neurologic examination, though controversy continues as to which neurologic criteria should be the ones leading to a cranial computed tomography scan. Understanding the anatomic variations in the radiography of the cervical spine in small infants and children can help avoid overdiagnosis in this group and can obviate the need for additional unwarranted computed tomography studies and undue clinical concern. Magnetic resonance imaging can show anatomically exquisite portrayals of growing skull fractures for neurosurgical planning, but its routine use for imaging the cervical cord in shaken, abused infants without clinical abnormality appears unwarranted. Within the chest, the radiograph remains a highly accurate and low cost cornerstone in traumatized patients. The use of ultrasound imaging to detect pleural fluid is being investigated and has been found to be accurate but cannot compare to all of the information gleaned from the radiograph. The pericardium is clearly an exception. Abdominal trauma in children is triaged vastly differently from that of adults. Imaging of adults looks for signs to diagnose significant bleeding and need for operation, while pediatric trauma imaging has its greatest effect in reducing the intensity of care. Administration of oral contrast has not been very effective in aiding diagnosis of hollow visceral perforations and is being used less in blunt abdominal trauma computed tomography. Children with microscopic hematuria and no evidence of multiple system trauma seem to be helped little by imaging. The utility of finding and extracting subcutaneous foreign material, usually in extremities, by ultrasound imaging remains controversial. Experience, equipment, and effort all seem to play a role.

Abdominal Injuries↗

PubMed2003

Clinical assessment and surgical implications of anatomic challenges in the anterior mandible.

BACKGROUND: The anterior mandible is generally considered a rather safe surgical area, involving few risks of damage to vital anatomic structures. Nevertheless, both neurosensory disturbances and hemorrhages have been reported after implant surgery in that particular area. PURPOSE: With the increasing demand for oral implant placement, the anatomy of the anterior mandible should receive more attention. This review will focus on the anatomic peculiarities of the anterior mandible and the related clinical implications. METHODS: The scientific evidence on the anatomic, histologic, physiologic, and clinical aspects of the neurovascularization of the anterior mandible will be reviewed. RESULTS: Surgical complications may be attributed to the existence of a mandibular incisive canal with a true neurovascular supply. Potential risks may also be related to the presence of the lingual foramen and anatomic variations, such as an anterior looping of the mental nerve. CONCLUSIONS: Preoperative radiographic planning for oral implant placement in the anterior mandible should therefore not only consider all esthetic and functional demands but should also pay particular attention to the anatomic peculiarities of this region to avoid any neurovascular complications.

Arteries↗

PubMed2005

Improving long-term breast shape with the medial pedicle wise pattern breast reduction.

BACKGROUND: Reduction mammaplasty has both a reconstructive and an aesthetic component. Relief of neck, back, and shoulder pain, as well as psychosocial improvement, is the main indication for intervention. Patient satisfaction is high, with early improvement in most cases. Preoperative planning confirms the anatomical variations as well as the best technique to achieve optimal cosmetic and functional results. Techniques for breast reduction have evolved in response to the great variety of challenges. The surgeon must tailor the surgical approach by considering a wide range of anatomic deformities, from gigantomastia to mild ptosis. Medial pedicle techniques have been shown to be reliable in severe breast hypertrophy. METHODS: The authors present a series of 88 consecutive patients who underwent reduction mammaplasty using a medial pedicle technique with a Wise pattern skin resection. The purpose of the study was to evaluate the complication rate, operative time, and long-term effects on pseudoptosis. RESULTS: The average weight reduction was 1814 g (both breasts combined), and the average operative time was 104.5 minutes. Patients were followed up for a minimum of 1 year, and the complication rate was 6.8 percent. The distance from the inframammary fold to the nipple was measured in patients with more than 1 year of follow-up. The results exhibited an average increase in this length of only 11 percent for reductions between 500 and 1200 g per side and of 34 percent for reductions greater than 1200 g per side. CONCLUSIONS: The authors conclude that this technique is an effective and reliable approach to a wide range of breast hypertrophy, with reproducible breast weight reduction and less long-term pseudoptosis or "bottoming out." In addition, the operative time is short and the complication rate is acceptably low.

Adult↗

PubMed2004

Pulmonary vein dimensions and variation of branching pattern in patients with paroxysmal atrial fibrillation using magnetic resonance angiography.

UNLABELLED: Pulmonary veins are the most frequent origin of focal and paroxysmal atrial fibrillation. Although radiofrequency ablation has been attempted for the treatment of focal and paroxysmal atrial fibrillation, the anatomy of the pulmonary vein is still not fully understood. To investigate the dimensions and anatomical variation of the pulmonary vein in patients with paroxysmal atrial fibrillation, we performed breath-hold gadolinium enhanced magnetic resonance (MR) angiography using a 1.5 T cardiac MR imager (GE CV/i) in 32 patients with paroxysmal atrial fibrillation (61 +/- 8 years old), 11 patients with chronic atrial fibrillation (64 +/- 9 years old), and 26 patients with normal sinus rhythm (55 +/- 15 years old). Three dimensional images of the pulmonary veins were thus obtained, and the diameters of the most proximal portion of the left or right superior pulmonary vein and left or right inferior pulmonary vein were measured. Pulmonary vein branching variations were determined by a visual qualitative analysis by two separate readers' agreements, who were blinded to any clinical information. We focused on the existence of a complex-branching pattern draining into the orifice of four pulmonary veins. Patients with either paroxysmal atrial fibrillation or chronic atrial fibrillation showed larger superior pulmonary veins than those with normal sinus rhythm (mean +/- SD; in the left superior pulmonary vein, 20 +/- 3 mm, 23 +/- 3 mm vs 16 +/- 3 mm, P < 0.05; in right superior pulmonary vein, 19 +/- 4 mm, 19 +/- 2 mm vs 16 +/- 2 mm, P < 0.05). Complex-branching pattern was frequently observed in inferior pulmonary veins in patients with either paroxysmal atrial fibrillation or chronic atrial fibrillation; 25/32 patients with paroxysmal atrial fibrillation, 11/11 patients with chronic atrial fibrillation, compared to 7/26 patients with normal sinus rhythm. Complex-branching patterns were not observed in superior pulmonary veins in any patients in this cohort. CONCLUSION: In patients with paroxysmal atrial fibrillation or chronic atrial fibrillation, significant pulmonary vein dilation occurred mainly in the superior pulmonary veins, while a complex-branching pattern was frequently observed in the inferior pulmonary veins. These MR angiographic findings might be useful when performing radiofrequency ablation procedures and catheter manipulation for the treatment of paroxysmal atrial fibrillation.

Aged↗

PubMed2005

Clinical significance of variations in the interconnections between flexor digitorum longus and flexor hallucis longus in the region of the knot of Henry.

Tendon transfer of the flexor digitorum longus tendon (FDLT) or the flexor hallucis longus tendon (FHLT) into the tibialis posterior tendon is carried out in patients with tibialis posterior dysfunction. FDLT and FHLT are connected in the region of the knot of Henry. The present study has investigated the anatomical variations of this tendinous interconnection. The results could be used to determine which of the two tendons should be transected proximal to the region of the knot of Henry in the surgical treatment of tibialis posterior dysfunction. In over two-thirds of cadaver specimens investigated, tension applied solely to FHLT resulted in flexion of all digits and the hallux. On the basis of these results, we propose that identification of the tendon to be transected should be decided at the time of surgery depending on the anatomical pattern. Based on the evidence provided by 16 cadaveric dissections, transection of FDLT proximal to the region of the knot of Henry for the repair of tibialis posterior dysfunction would result in retention of function of the hallux and lesser digits in the majority of cases.

Cadaver↗

PubMedDate not supplied

Planning of liver surgery using three dimensional imaging techniques.

In the simplified Couinaud classification, in which the liver is divided into eight segments, each supplied by a central vasculo-biliary sheath, little attention is given to the high prevalence of anatomical variations which occur, especially in the right hemiliver. Using volumetric acquisition techniques, such as magnetic resonance imaging or spiral computed tomography scanning, detailed insight into the individual segmental anatomy can now be obtained in a non-invasive manner. The significance of this anatomical insight lies in the planning of anatomical resections, whereby the relationship between tumour and individual segmental anatomy can be depicted in a three-dimensional format. As such, three dimensional (3D) liver imaging helps to design an individualised resection, tailored to the topographical relationship between individual segmental anatomy and tumour tissue present. Three dimensional liver imaging is of most practical value if a resection of one or more segments or sectors is considered, especially in the right hemiliver. In these cases, 3D liver imaging can demonstrate the precise location of the scissuras to the surgeon pre-operatively.

Colorectal Neoplasms↗

PubMed1977

The middle cranial fossa approach to the internal auditory canal -- an anatomical study stressing critical distances between surgical landmarks.

The middle cranial fossa approach to the internal auditory canal and petrous apex has proven to be an extremely useful otologic surgical procedure. Ths historical evolution of this approach and its present day application were reviewed. The purpose of the study was to describe the normal anatomical variations encountered during the course of the middle cranial fossa approach to the internal auditory canal. Measurements between surgical landmarks were made on 20 dissected, and 41 histologically sectioned temporal bones. The values obtained were statistically analyzed. Finally, the practical implication of the observed anatomical measurements and of the statistical evaluations were discussed.

Adolescent↗

PubMed1993

Anatomical differences of port-wine stains in response to treatment with the pulsed dye laser.

BACKGROUND AND DESIGN: Anecdotal reports and clinical observations have suggested that the response of port-wine stains to treatment with the pulsed dye laser is variable and dependent on the anatomical location of the lesion. To investigate anatomical variation in response to treatment, a retrospective study of 259 adults and children with port-wine stains of the head and neck treated with the pulsed dye laser was undertaken. Evaluation was performed by comparing simultaneously projected pretreatment and completion-treatment photographs. Anatomical differences in response were evaluated in three ways: (1) by anatomical subdivision of the head and neck into regions, (2) by dermatomal distribution, and (3) by response for midline lesions. The head and neck was subdivided into eight anatomical regions, which were independently evaluated for response. In addition, response for individual dermatomes and for midline lesions was evaluated. Response in all cases was assessed by determining the percentage of lightening from 0% to 100% (where 100% represents complete response) at the completion of treatment. Response grades were also assigned, using grades poor (0% to 25% lightening), fair (26% to 50% lightening), good (51% to 75% lightening), or excellent (76% to 100% lightening). RESULTS: One hundred thirty-seven adults and 122 children were included in the study. Evaluation by subdivision of the head and neck into regions revealed that in adults and children the centrofacial regions (medial aspect of the cheek, upper cutaneous lip, and nose) responded less favorably than the other grouped regions (periorbital, forehead/temple, lateral aspect of the cheek, neck, and chin); the centrofacial regions showed a good response (mean lightening, 70.7%) while the other grouped regions of the head and neck showed an excellent response (mean lightening, 82.3%). Evaluation by dermatomal distribution revealed that dermatome V2 showed a good response (mean lightening of 73.8%), while combined dermatomes V1, V3, and C2/C3 showed an excellent response (mean lightening of 82.4%). Evaluation of midline lesions revealed excellent responses in adults and children (mean lightening, 92.4%). CONCLUSIONS: Port-wine stains of the head and neck in adults and children demonstrate differences in response to treatment with the pulsed dye laser according to their anatomical location. Centrofacial lesions and lesions involving dermatome V2 in adults and children respond less favorably than lesions located elsewhere on the head and neck. Midline lesions respond very favorably in adults and children.

Adolescent↗

PubMed1986

Methods for the study of the human foetal arterial system.

Microarteriography followed by enlargement of the photographs, resin cast preparation and serial sections were techniques applied to study the arterial system of the human foetal abdomen from 12 to 20 weeks ovulation age. In order to illustrate the advantages of these techniques, the blood supply of the second portion of the duodenum of the developing foetus was demonstrated for the first time. Particular attention was directed to the recognition of anatomical variations. Vascular patterns were found to be complete in the age group studied.

Abdomen↗

PubMed2006

Relationship between variations in the circle of Willis and flow rates in internal carotid and basilar arteries determined by means of magnetic resonance imaging with semiautomated lumen segmentation: reference data from 125 healthy volunteers.

BACKGROUND AND PURPOSE: Volume flow rates in the feeding arteries of the brain are measured to evaluate blood flow dynamics in vascular disease. Although these flow values are thought to be effected by anatomic variations in the circle of Willis, few reports have described the effect. This study reports on the relationship between variations in the circle of Willis and volume flow rates in the bilateral internal carotid and basilar arteries of normal volunteers. METHODS: We prospectively examined 125 healthy volunteers by MR imaging. Variations in the circle of Willis were classified as "textbook" type, hypoplasia of the precommunicating segment of the anterior cerebral artery (A1), hypoplasia of the precommunicating segment of the posterior cerebral artery (P1), or "other." Volume flow rates were measured by 2D cine phase-contrast MR imaging. Lumen boundaries and volume flow rates were semiautomatically determined by pulsatility-based segmentation. RESULTS: Of the 117 subjects (61 men, 56 women; mean age, 23.6 years) considered suitable for flow measurement, 105 showed textbook type, and 6 each showed A1 hypoplasia and P1 hypoplasia. Total flow rates for the 3 variations were 781 +/- 151 mL/min (mean +/- SD), 744 +/- 119, and 763 +/- 129, respectively. Relative contributions by flow rates of the internal carotid arteries and the basilar artery for the 3 variations were 39.8%:38.9%:21.3%, 31.8%:49.1%:19.0%, and 46.6%:41.6%:11.7%, respectively, showing statistically significant differences. CONCLUSIONS: Variations in the circle of Willis correlate significantly with relative contributions by the flow rates of the bilateral internal carotid and basilar arteries.

Adult↗

PubMed2004

Skin blood flow pattern in burns outcomes.

Functional microcirculatory aspects of burned sites were examined including areas of self-healed burns, and grafted areas. Donor areas were also examined. In 10 patients with burns in the lower limbs, both self-healed and with grafts, the microcirculatory response was evaluated by Laser Doppler flowmetry (LDF) measuring for each site the resting flux at 36 degrees, the postural venular-arteriolar reflex (VAR) and the flux at 41 degrees (heating). The first evaluation was carried out on discharge, and subsequently at approximately 45 day intervals during uniform therapy follow-up (elastocompression). The burn-affected area (self-healed, graft) and those donor areas present should increase resting flux by comparison with control areas. This was particularly so in the self-healed burn, which does however tend to converge in time towards control values. Response to stress tests (VAR and heating) presents percentage variations similar to normal skin in the various areas, with the exception of the grafted areas which present a reduced response in the 1st weeks following engraftment. No significant differences in response to heating were detected. It can be suggested that these differences are due to anatomic variations in revascularization and healing in the different areas as well as to alterations in microvascular innervation and local response to vasoactive substances.

Adult↗