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At least 73 records · Page 4Linked to original sources
PubMed2001

Cavernosal arterial anatomic variations and its effect on penile hemodynamic status.

OBJECTIVE: With continuous improvements in ultrasound technology, small vessels with remarkably slow blood flow that may not be assessed by color Doppler ultrasonography, can be evaluated using power Doppler ultrasonography. In the present study, penile arterial anatomic variations were determined with power Doppler ultrasonography and its impact on penile hemodynamic status. METHODS: A total of 54 patients with erectile dysfunction were evaluated with power Doppler ultrasonography. The effects of vascular anatomic variations and the structure of the corpora cavernosa and tunica albuginea on vascular status were assessed on both sides. RESULTS: A normal penile vascular system was observed in 35.2% and 25% of 54 patients (mean age: 46.6+/-11.5 years) at the radix and mid-shaft of the penis, respectively. Pure arterial component was observed in 40.7% (22/54) and 47.2% (17/36) of the patients at the base and mid-shaft of the penis, respectively. Penile arterial insufficiency was severe in 9.2 and 5.5% of the patients at the base and mid-shaft of the penis, respectively, whereas intrapenile truncus was found in six patients (5.5%), the ratio of single cavernosal artery, intrapenile and extrapenile bifurcations were 69.4, 7.4 and 12.0%, respectively. Twenty (18.5%) dorso-cavernosal perforators, 15 (13.9%) cavernoso-dorsal and 30 (27.8%) intercavernosal branches were found. Peak systolic blood flow velocity values were decreased in 12 of 36 patients (33.3%) distally, while increased blood flow was observed in 11 (30.5%). CONCLUSIONS: Hemodynamic parameters might be variable at either side of the penis and depend on intrapenile arterial anatomic variations. Parameters determined using power Doppler ultrasonography should be evaluated from the proximal to distal side of the penis to obtain reliable and standard results. However, variations of penile arterial anatomy and its effect on penile hemodynamic changes should not be overlooked especially in the patients who are candidates for penile reconstructive or vascular surgery.

Adult↗
PubMed1998

Anatomic variations and technical problems of the anterolateral thigh flap: a report of 74 cases.

We have transferred 74 free or pedicled anterolateral thigh flaps, including those combined with other flaps, for reconstruction of various types of defects. We report several anatomic variations of the lateral circumflex arterial system and discuss some technical problems with this flap. Septocutaneous perforators were found in 28 of 74 cases (37.8 percent), and no perforators were found in 4 cases (5.4 percent). In the 70 cases with perforators, 171 tiny cutaneous perforators (an average of 2.31 per case) were found. Musculocutaneous perforators (81.9 percent) were much more common than septocutaneous perforators (18.1 percent). Perforators were concentrated near the midpoint of the lateral thigh, and the selection of perforators as nutrient vessels for the anterolateral thigh flap was related to the length of the pedicle and the thickness of the skin flap. Anatomic variations of the branching pattern of perforators were classified into eight types. Flaps with perforators that arise directly from the profunda femoris artery are difficult to combine with other free flaps. Because the perforators are extremely small and tend to thrombose soon after congestion develops, these flaps are difficult to salvage with recirculation surgery. Therefore, several perforators should be included with the flap, if possible. The descending artery of the lateral circumflex femoral artery was always accompanied by two veins with different back-flow strengths. Therefore, veins for microsurgical anastomosis must be chosen carefully. Because it is nourished by several perforators arising from the descending artery, the vastus lateralis muscle can be combined with the anterolateral thigh flap. However, splitting the muscle longitudinally without harvesting its blood supply is complicated because its fibers are oblique. The rectus femoris muscle can also be combined with the anterolateral thigh flap, but its pedicle is short and its origin is very near the site of anastomosis. When the anterolateral thigh flap is combined with the tensor fasciae latae musculocutaneous flap, the large skin area of the lateral part of thigh can be transferred to repair the massive defects. The anterolateral thigh flap has many advantages and can be used to reconstruct many types of defect. However, anatomic variations must be considered if the flap is to be used safely and reliably.

Adolescent↗
PubMed2001

Anatomical variations in the human testicular blood vessels.

The testis is an important organ upon which the survival of the human species depends. The testicular arteries and veins play major roles in the thermo-regulation that is essential for the efficient functioning of this organ. However, very little is found in the literature about the veins and their anatomical variations. Therefore the testicular veins and arteries in 150 dissection room cadavers at the University of the Witwatersrand, Johannesburg and University of Zimbabwe, Harare were examined for anatomical variations from the usual descriptions in textbooks of Anatomy. Variations were found more frequently in the testicular veins than in the accompanying arteries. The variations, which were more common on the left side, were seen in 32 (21.3%) of the cadavers. In 6 (18.8%) of these cases, the variations were present bilaterally. The veins were either completely or partially duplicated, with or without beading. The duplicated veins terminated in the corresponding renal veins either separately or after combining into one vein. In two cases, the right testicular vein terminated in the right renal vein, rather than in the inferior vena cava. Anatomical variations of the testicular artery were present in 4.7% of cases and were associated with their origin, which were either from unusually high levels of the abdominal aorta or from the renal artery.

Arteries↗
PubMed1989

Closed intramedullary nailing of diaphyseal fractures of the femur. Problems related to anatomical variations of the greater trochanter.

An examination of the radiographs of 100 normal femurs revealed an anatomical variation consisting of lateralization of the trochanteric mass in relation to the femoral diaphysis. This involves disalignment of the apex of the greater trochanter in relation to the medullary canal, with consequent complications during closed intramedullary nailing such as varus of the fracture segments, valgus of the nail, fracture of the medial cortex. Since becoming aware of this anatomical variation and its possible consequences, the authors now carry out routine preoperative A.P. radiographs of the contralateral femur and if lateralization of the trochanteric mass is observed, the nail is not inserted at the apex of the greater trochanter but at the base of the femoral neck in order to restore alignment of the nail with the femoral diaphysis.

Adult↗
PubMed2006

Brachial loop: transradial technique to overcome this rare anatomic variation.

A brachial loop is a rare anatomic variation and can result in the failure of transradial coronary procedures. We report a brachial loop encountered in a patient undergoing a coronary angiogram. During this angiogram, a 0.035'' J-tipped Teflon-coated guidewire met with resistance in the brachial artery because of this rare vascular loop. In this case report, we discuss the technique we used to manage this rare condition. Interventional cardiologists should keep in mind that resistance of the guidewire can result in major vessel complications during the transradial approach.

Aged, 80 and over↗
PubMed2006

Common hepatic artery arising from the left gastric artery: a rare anatomic variation identified on a cadaveric liver donor.

Anatomical variations of the arterial supply of the liver are not uncommon. The typical normal "textbook" anatomy of the hepatic artery is found only in approximately half of the cases. Some of the variations such as the presence of a right or left hepatic branch are more common, but other ones are extremely rare. We describe here a rare case in which the common hepatic artery arose from the left gastric artery, found during a cadaveric liver donor harvesting and confirmed with imaging studies. Cases like this one highlight the importance of knowing the hepatic arterial anatomy and the possibility of its numerous variations by the transplant and hepatobiliary surgeon.

Cadaver↗
PubMed2004

Anatomic variations in right liver living donors.

BACKGROUND: Anatomic knowledge is crucial in right liver living donor transplantation. STUDY DESIGN: We reviewed radiologic and surgical findings in right liver donors. Arterial and portal anatomy was assessed in 96 donors, biliary anatomy in 77, and hepatic venous anatomy in 65. RESULTS: Portal vein (PV): 86.4% had classic anatomy; 6.3% had a trifurcated PV; 7.3% had a right anterior PV taken off the left PV. Hepatic artery (HA): 70.8% had classic anatomy; 12.5% had a left HA arising from the left gastric artery; 13.5% had a right HA arising from the superior mesenteric artery; 2.1% had a double replaced left HA and right HA; and in 1.0% the common HA arose from the superior mesenteric artery. Biliary tree: 55.8% had normal anatomy; 14.3% had a trifurcated biliary anatomy; in 5.2% the right anterior bile duct and in 15.6% the right posterior bile duct opened into the left bile duct; in 2.6% the right anterior and in 6.5% the right posterior ducts opened into the common bile duct. Hepatic veins: S5 and S8 accessory hepatic veins had incidences of 43% and 49%, respectively. The incidence of S6 or S7 short hepatic vein was 38%. CONCLUSIONS: Anatomic variations are common but do not contraindicate donation; surgeons should be prepared to recognize and manage them.

Adult↗
PubMed1990

Anatomic variations of the midcarpal joint.

Two distinct anatomic variations in the human midcarpal joint have been identified. In type I the triquetrohamate joint is on a smooth oblique plane with the capitolunate joint. In type 2 the triquetrohamate joint is separated from the capitolunate joint by a concave transition facet on the hamate and lunate. Degenerative change occurring at the proximal pole of the hamate and the opposing transition facet on the lunate have been identified as characteristic of both a type 2 joint and lunotriquetral interosseous ligament tears.

Aged↗
PubMedDate not supplied

Anatomic variations of the chorda tympani canal.

The anatomic variations of the facial recess are of interest in certain otosurgical procedures. The medial border of the recess is the mastoid portion of the facial nerve canal, and the lateral border is the bony canal of the chorda tympani. These two structures were investigated in 64 polyester casts of temporal bone specimens. The point of exit of the chorda tympani canal from the facial canal was assessed together with the angle, formed between these two nerve channels. As a further way of describing the spaciousness at the facial recess, the distance between the sulcus of the stapedius muscle and the chorda tympani canal was evaluated.

Chorda Tympani Nerve↗
PubMedDate not supplied

Anatomical variations of the abducent nerve in humans.

Anatomical variation of the nervus abducens in human encephali were found and described. They consisted of (1) an unusual trifurcation of the abducent nerve, limited to the extradural portion of the neural trunk (1.4% of the cases) and (2) the duplicity (11.1%) of the neural trunk, starting before reaching the orbit and ending before reaching the m. rectus lateralis. The possibility of correlating these variations with clinical aspects and forensic interpretations is mentioned.

Abducens Nerve↗
PubMed1977

[Anatomical variations and taxonomic relatedness in Hominoidea].

31 anatomical variations were examined in 125 Pan paniscus and 96 Gorilla gorilla beringei skulls. Comparisons with published data of Hominoidea show that differences in their frequencies are proportional and parallel to taxonomic relationships on the subspecific, specific and generic level.

Animals↗
PubMed2000

Anatomic variations of anterior cerebral artery cortical branches.

The anterior cerebral artery (ACA) is a major vessel responsible for the blood supply to the interhemispheric region. The ACA segment after the anterior communicating artery (AComA) origin is called the distal ACA and has central and cortical branches. The cortical branches are distributed in the different regions of the orbital and medial part of the brain. The objects of this study are the anatomical variations found in the distal ACA. In 76 hemispheres the ACA distal branches were injected with latex and dissected under microscope magnification. Vessel diameters and distances between vessel origins and anterior communicating artery were recorded and analyzed. Microsurgical dissection was carried out to demonstrate anatomic variations of these vessels. Average diameter of ACA at origin was 2.61 +/- 0.34 mm and average diameter of cortical branches diameter ranged from 0.79 +/- 0.27 mm to 1.84 +/- 0.3 mm. Distances between vessel origin and AComA ranged from 7.68 +/- 3.91 mm (orbitofrontal) to 112.6 +/- 11.63 mm (inferior internal parietal). This study found anatomical variations: a single (azygos) ACA was present in one case and three in three cases. Crossing branches of the distal ACA to the contralateral hemisphere were present in 26% of the cases. In some cases a single ACA may supply the posterior hemispheric region through crossing branches. This calls attention to potential bilateral brain infarcts due to a single unilateral ACA occlusion.

Anterior Cerebral Artery↗
PubMed1991

Anatomical variations of internal jugular vein location: impact on central venous access.

OBJECTIVE: To evaluate whether underlying anatomical variations in the position of the internal jugular vein may account for difficulty in obtaining central venous access in individual patients. DESIGN: Consecutive series. SETTING: Cardiac catheterization laboratory, coronary care unit, and ICU. PATIENTS: Two hundred patients (52 +/- 7 yrs, 147 males) who were undergoing internal jugular vein cannulation for hemodynamic monitoring or endomyocardial biopsy. INTERVENTION: The internal jugular vein and carotid artery were visualized with two-dimensional ultrasound and their position was compared with their projected location from external landmarks. RESULTS: In 183 (92%) patients, the position of the internal jugular vein was lateral and anterior to the carotid artery and increased in diameter during a Valsalva maneuver. In five (2.5%) patients, the internal jugular vein was not visualized and was probably thrombosed, as the internal jugular vein was normal on the other side. In six (3%) patients, the internal jugular vein was unusually small and did not increase in diameter during the Valsalva maneuver. In two (1%) patients, the internal jugular vein was positioned greater than 1 cm lateral to the carotid artery. Four (2%) patients had a medially positioned internal jugular vein overlying the carotid artery. In 5.5% of the patients, the position of the internal jugular vein was outside the path that had been predicted by the external landmarks. CONCLUSIONS: These findings suggest that anatomical variation may partly account for the inability to cannulate the internal jugular vein in certain patients. In these cases, ultrasound examination quickly establishes the position of the internal jugular vein and may allow for easy and rapid access.

Carotid Arteries↗
PubMed1993

[Surgical applications of anatomical variations of the median nerve at the wrist].

After a brief report of median nerve anatomy at wrist, authors describe terminal variations of its distribution. Classic description of five terminal sensitive and motor median nerve branches is not constant. Many anatomic variations have been reported and so many, classifications proposed. Lantz' classification is useful, it may be divided in four groups. Other anatomic variations concern cutaneous palmar nerve branch and different nervous anastomosis. Advantage of this anatomic study is incidence of variations on surgical access of carpal tunnel. Those nervous variations of median nerve at wrist are frequent, unknown and wrong indexed and may be so many "anatomic traps" for surgeon.

Anatomy, Regional↗
PubMed2006

Anatomical variations of the V2 segment of the vertebral artery.

OBJECTIVE: Our goal was to evaluate the incidence of anatomic variations of the V2 segment (from its entrance into the transverse canal to C2) of the vertebral artery. Ignoring such variations during anterior or lateral approach to the cervical spine can lead to inadvertent injury and potentially serious complications. METHODS: We studied the course of 500 vertebral arteries on 200 magnetic resonance imaging and 50 contrast-enhanced computed tomographic scans. RESULTS: The vertebral artery entered the C6 transverse foramen in 93.0% of all specimens. An abnormal level of entrance was observed in 7.0% of specimens (35 courses), with a level of entrance into the C3, C4, C5, or C7 transverse foramen, respectively, in 0.2% (n = 1; 2.9% of all anomalies), 1.0% (n = 5; 14.3% of all anomalies), 5.0% (n = 25; 71.4% of all anomalies), and 0.8% (n = 4; 11.4% of all anomalies) of all specimens. Seventeen (48.6%) abnormalities were right-sided and 18 (51.4%) were left-sided. Thirty-one out of 250 patients (12.4%) had a unilateral anomaly and two had a bilateral anomaly (0.8%). In cases of abnormal entrance into the transverse foramen on computed tomographic images (n = 6), the area of the unfilled transverse foramens was significantly smaller than the contralateral filled foramen (P < 0.0001) and was significantly smaller than the filled foramen of all patients at the same level (P < 0.0001). In five patients (2.0%), the vertebral artery formed a medial loop either into an unusually large transverse foramen whose internal border was medial to the uncovertebral joint or into the intervertebral foramen. CONCLUSION: The incidence of anatomic variations of the vertebral artery V2 segment is high. Potentially dangerous conditions can be detected on preoperative imaging.

Anthropometry↗
PubMed2005

Anatomical variations of rami communicantes in the upper thoracic sympathetic trunk.

OBJECTIVE: The aim of this study was to clearly delineate the anatomical variations of the communicating rami in the upper thoracic sympathetic nervous system and to help develop better surgical method for essential palmar hyperhidrosis. METHODS: Anatomical dissections of the upper thoracic sympathetic chains with sympathetic ganglia and communicating rami have been carried out in 42 adult Korean cadavers (male 26, female 16). The rami communicantes were classified into three types (Normal: transverse or oblique rami connected to the intercostal nerve of the same level; AR: ascending rami connected to the higher level; DR: descending rami to the lower level) based on the anatomical relationship of the thoracic sympathetic ganglia to the intercostal nerves. Both sides of the upper thoracic sympathetic nervous system were compared in the same individual. The number of the communicating rami was recorded in 32 cadavers (64 sides). The distance from the rami communicantes to the sympathetic trunk was measured in 26 cadavers (52 sides). RESULTS: The incidence of AR (ascending rami) and DR (descending rami) arising from the second sympathetic ganglion was 53.6% (45/84), 46.4% (39/84). From the third thoracic sympathetic ganglion, the incidence of AR was 5.9% (5/84) and that of DR was 26.2% (22/84). And in the fourth thoracic sympathetic ganglion, the incidence of AR was 4.8% (4/84) and DR was 8.3% (7/84), respectively. When we compared anatomical structures of both sides among the 42 cadavers dissected, only 14.3% (6/42) had similar anatomy of the rami communicantes bilaterally. Among 32 cadavers (64 sides), the mean number of rami communicantes at the second thoracic sympathetic ganglion was 2.1/2.5 in the left and the right side. At the third and the fourth thoracic sympathetic ganglion, the mean number was 1.9/1.6 and 1.7/1.7 in each side. The mean distance from the thoracic sympathetic chain to the most distal communicating rami of the left and right side at the second intercostal nerve was 7.81/9.40 mm among 26 cadavers. The mean distance of each side was 6.81/7.94 mm at the level of the third intercostal nerve. And at the level of the fourth intercostal nerve, the mean distance was 7.48/10.92 mm, respectively. CONCLUSION: On the basis of this study, the anatomical variations of communicating rami could explain some surgical failures and recurrences. Moreover, in addition to the conventional surgical methods (sympathectomy, sympathicotomy, clipping of sympathetic chain and ramicotomy), dividing the inconstant sympathetic pathways (nerve of Kuntz, ascending or descending rami communicantes) on the second, the third and the fourth ribs will help to get better surgical effect.

Adult↗
PubMedDate not supplied

[Role of anatomic variations and methods of hepatic artery reconstruction in the incidence of thrombosis following liver transplantation].

AIM: The aim of this study was to investigate the incidence of anatomic variations of hepatic artery (HA) in order to evaluate if anatomical anomalies may be associated with an increased incidence of hepatic artery thrombosis (HAT) after orthotopic liver transplantation (OLT). Moreover, we focused on arterial reconstructive technique associated with a low incidence of HAT. METHODS: We reported a consecutive series of 687 OLT in 601 patients (1986-1999). Hepatic arterial reconstruction was variable and dependent upon donor and recipient anatomy, even if arterial anastomosis was mainly of two types: the end-to-end anastomosis (EEA), used in 340/687 OLT (49.4%) and the branch patch anastomosis (BPA), performed in 347/687 OLT (50.5%). Interrupted sutures of 7/0 polypropylene always were used. RESULTS: The diagnosis of HAT was made in 17/687 patients (2.47%). Anomalous hepatic arteries were found in 5/17 cases (29.4%). In the EEA group HAT occurred in 12/340 patients (3.53%), whereas in the BPA group HAT was diagnosed in 5/347 cases (1.44%) (p = 0.078). DISCUSSION: Anatomic variations of HA, most frequently observed, were the left hepatic artery originating from the left gastric artery (9.7-18%) and the right hepatic artery originating from the superior mesenteric artery (7.5-18%). There was no increased incidence of HA complications in the presence of HA anomalies in the donor. Moreover, the existence of an anomaly in the recipient HA was not important if it had appropriate size anf flow. CONCLUSIONS: In our series, the branch patch technique, using the hepatic-gastroduodenal bifurcation, was our current preferred method of arterial anastomosis, with a HAT-rate of 1.44%.

Adult↗