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Biomedical subjects

Gen Murakami

Publications and source records attributed to Gen Murakami.

At least 19 recordsLinked to original sources
PubMed2007

A clinicoanatomical study of the novel nerve fibers linked to stress urinary incontinence: the first morphological description of a nerve descending properly along the anterior vaginal wall.

When performing anterior colporrhaphy for cystocele, most pelvic surgeons have not considered the neuroanatomy that contributes to urethral function. The aim of the study was to anatomically identify nerve fibers located in the anterior vagina associated with the pathogenesis of incontinence and pelvic organ prolapse. Anterior vaginal specimens were obtained from 17 female cadavers and 33 cases of clinical cystocele by anterior vaginal resection. The specimens were step-sectioned and stained with hematoxylin-eosin, S100 antibody, and tyrosine hydroxylase antibody. As a result, descending nerves 50-200 microm in thickness were identified between the urethra and vagina. They were located more than 10 mm medially from a cluster of nerves found almost along the lateral edge of the vagina and stained with S100 and tyrosine hydroxylase antibody, originated from the cranial part of the pelvic plexus, and appeared to terminate at the urethral smooth muscles. The authors classified the density of S100 positive nerve fibers in the anterior vaginal wall obtained from clinically operated cases of cystocele into three grades (Grade 1, nothing or a few thin nerves less than 20 microm in diameter; Grade 2, thick nerves more than 50 microm in diameter and thin nerves; Grade 3, more than 3 thick nerves in one field at an objective magnification of 40x). Mean urethral mobility (Q-tip) values (28.1 degrees +/-+/- 19.6 degrees ) observed in the Grade 3 cases was significantly lower than those (50.0 degrees +/-+/- 27.4 degrees and 59.4 degrees +/-+/- 19.9 degrees ) in Grade 2 and Grade 1, respectively. In addition, the presence of preoperative or postoperative stress urinary incontinence in the cases of Grade 1 was significantly higher than those of the cases with S100 positive stained nerves. In conclusion, the novel nerve fibers immunohistochemically identified in the anterior vaginal wall are different from those of the common nervous system or the pelvic floor and are associated with the pathogenesis of urethral hypermobility.

Aged↗
PubMed2007

Pelvic autonomic nerve mapping around the prostate by intraoperative electrical stimulation with simultaneous measurement of intracavernous and intraurethral pressure.

PURPOSE: In previous studies we noted that the neurovascular bundle was not identical to the bundle of the cavernous nerve fibers. In this study we sought to prove these anatomical findings electrophysiologically and map the autonomic nerve fibers by intraoperative simultaneous measurement of intracavernous pressure and intraurethral pressure. MATERIALS AND METHODS: Between January 2004 and May 2005 electrical stimulation was performed in 27 open pelvic surgeries, including 26 radical retropubic prostatectomies and 1 radical cystectomy, using an original bipolar electrode before prostate removal. Nerve stimulation was performed at the base of the so-called neurovascular bundle (point A) and the rectal wall about 1 cm posterolateral, apart from the neurovascular bundle (point B). Intracavernous pressure and intraurethral pressure were measured simultaneously. RESULTS: The mean +/- SD increase in intracavernous pressure was 9.8 +/- 6.3 cm H2O at point A and 13.5 +/- 7.3 cm H2O at point B. Intracavernous pressure at point B was significantly higher than at point A (p = 0.0240). The mean increase in intraurethral pressure was 17.0 +/- 9.4 cm H2O at point A and 11.2 +/- 8.1 cm H2O at point B. Intraurethral pressure at point A was significantly higher than at point B (p = 0.0353). CONCLUSIONS: The course of the cavernous nerves did not always agree with the surgically identified neurovascular bundle. The distribution of cavernous nerves was wider than our image of the neurovascular bundle and it existed on the rectal wall posterolateral, apart from the neurovascular bundle rather than the neurovascular bundle itself. The surgically identified neurovascular bundle contained the nerve fibers contributing to urinary continence.

Aged↗
PubMed2006

Local neurosteroid production in the hippocampus: influence on synaptic plasticity of memory.

In neuroendocrinology, it is believed that steroid hormones are synthesized in the gonads and/or adrenal glands, and reach the brain via the blood circulation. In contrast to this view, we are in progress of demonstrating that estrogens and androgens are also synthesized locally by cytochrome P450s in the hippocampus, and that these steroids act rapidly to modulate neuronal synaptic plasticity. We demonstrated that estrogens were locally synthesized in the adult hippocampal neurons. In the pathway of steroidogenesis, cholesterol is converted to pregnenolone (by P450scc), dehydroepiandrosterone [by P450(17alpha)], androstenediol (by 17beta-hydroxysteroid dehydrogenase, 17beta-HSD), testosterone (by 3beta-HSD) and finally to estradiol (by P450arom) and dihydrotestosterone (by 5alpha-reductase). The basal concentration of estradiol in the hippocampus was approximately 1 nM, which was greater than that in blood plasma. Significant expression of mRNA for P450scc, P450(17alpha), P450arom, 17beta-HSD, 3beta-HSD and 5alpha-reductase was demonstrated by RT-PCR. Their mRNA levels in the hippocampus were 1/200-1/5,000 of those in the endocrine organs. Localization of P450(17alpha) and P450arom was observed in synapses in addition to endoplasmic reticulum of principal neurons using immunoelectron microscopy. Different from slow action of gonadal estradiol which reaches the brain via the blood circulation, hippocampal neuron-derived estradiol may act locally and rapidly within the neurons. For example, 1 nM 17beta-estradiol rapidly enhanced the long-term depression (LTD) not only in CA1 but also in CA3 and dentate gyrus. The density of thin spines was selectively increased within 2 h upon application of 1 nM estradiol in CA1 pyramidal neurons. Only ERalpha agonist propyl-pyrazole-trinyl-phenol induced the same enhancing effect as estradiol on both LTD and spinogenesis in the CA1. ERbeta agonist hydroxyphenyl-propionitrile suppressed LTD and did not affect spinogenesis. Localization of estrogen receptor ERalpha in spines in addition to nuclei of principal neurons implies that synaptic ERalpha can drive rapid modulation of synaptic plasticity by endogenous estradiol.

Androgens↗
PubMed2006

Comparison between basal and apical dendritic spines in estrogen-induced rapid spinogenesis of CA1 principal neurons in the adult hippocampus.

Modulation of hippocampal synaptic plasticity by estrogen has been attracting much attention. Here, we demonstrated the rapid effect of 17beta-estradiol on the density and morphology of spines in the stratum oriens (s.o., basal side) and in the stratum lacunosum-moleculare (s.l.m., apical side) by imaging Lucifer Yellow-injected CA1 neurons in adult male rat hippocampal slices, because spines in s.o. and s.l.m. have been poorly understood as compared with spines in the stratum radiatum. The application of 1nM estradiol-induced a rapid increase in the density of spines of pyramidal neurons within 2h. This increase by estradiol was blocked by Erk MAP kinase inhibitor and estrogen receptor inhibitor in both regions. Effect of blockade by agonists of AMPA receptors and NMDA receptors was different between s.o. and s.l.m. In both regions, ERalpha agonist PPT induced the same enhancing effect of spinogenesis as that induced by estradiol.

6-Cyano-7-nitroquinoxaline-2,3-dione↗
PubMed2006

Human pelvic extramural ganglion cells: a semiquantitative and immunohistochemical study.

In pelvic surgery, much attention is paid to nerve bundles but not to ganglion cells. Using serial section histology of 14 postmortem-treated hemipelvis (eight males, six females; mean, 79 years old), we examined the population number, distribution, and tyrosine hydroxylase-immunoreactivity (TH-IR; suggesting sympathetic neurons) of extramural pelvic ganglion cells. All pelvic ganglion cells were uniformly sized (25-30 microm) contrasting with small intramural rectal neurons. Abundant ganglion cells (30,000-140,000 unilaterally) existed not only along the pelvic viscera except for the rectum, but also along the hypogastric nerve, pelvic splanchnic nerve, pelvic plexus, and associated branches excluding those within the mesorectum. The intrapelvic ganglion cells outside the sympathetic trunk did not form macroscopically identifiable ganglia, but made small clusters (0.1-2.0 mm of maximum diameter) or were diffusely scattered within nerve bundles. More than half of these cells appeared TH-IR positive, although the positive/negative proportion differed between nerves and specimens. Greater numbers of ganglion cells were found in dorsosuperior sites (e.g., around the seminal vesicle) rather than in ventroinferior sites (e.g., along the urethra) in males, and vice versa in females. However, in total cell numbers, interindividual variations were evident rather than intergender difference. Due to significant interindividual variations in cell number, differences are likely to exist between patients in "resistance" to surgical stresses. We hypothesized that pelvic ganglion cells are liable to be damaged due to drying along the surgical margin, hypoxia in venous bleeding, pressure from surgical retractors, extension stress with taping and excess traction and/or direct injury with electrical scalpels.

Aged↗
PubMed2006

Strain on the repaired supraspinatus tendon during manual traction and translational glide mobilization on the glenohumeral joint: a cadaveric biomechanics study.

There has been no report on the mechanical effects of joint mobilization on rotator cuffs. The purpose of this study was to determine whether it is safe to use grade 3 joint mobilization techniques after rotator cuff repair. Nine fresh frozen cadaveric shoulders were used in this study. The strains on the artificially repaired supraspinatus tendon during joint mobilization were measured at 0 degrees and 30 degrees of shoulder abduction and were compared with those at the maximal stretching position and relaxing position. Additionally, gap distances were measured during this experiment. The strain at 30 degrees of abduction of the repaired tendon during each joint mobilization was significantly smaller than that at 0 degrees abduction (P<0.05). At 30 degrees of abduction, the strain during joint mobilization was not statistically different from that of the shoulder in the relaxing position, except during the inferior glide technique. Gap distances were 0mm at 30 degrees , while the distances were 1.06-1.46 mm at 0 degrees. Our findings suggest that joint mobilization techniques, except inferior glide, can be performed safely without significantly straining the repaired tendon at 30 degrees of abduction, if rotator cuff repair is performed at 0 degrees of abduction.

Aged↗
PubMed2006

Preservation of the puboprostatic collar and puboperineoplasty for early recovery of urinary continence after robotic prostatectomy: anatomic basis and preliminary outcomes.

OBJECTIVES: The aims of the present study are to prove the hypothesis that the preservation of the puboprostatic collar and puboperineoplasty contribute to the early recovery of urinary continence after robotic radical prostatectomy. We reconfirm the anatomy of the periurethral supporting tissue and show the preliminary result on the early continence of patients undergoing this modification. METHODS: Using 10, male, fresh cadavers, we traced the endopelvic fascia, the fascia of levator ani, puboprostatic ligaments, rhabdosphincter, and puboperinealis muscle to devise strategies in preserving this complex. The modifications were then attempted by a single surgeon (A.K.T.) in 19 patients undergoing robotic prostatectomy during September 2005. RESULTS: After incision of the endopelvic fascia within the fascial tendinous arch of the pelvis, the puboprostatic collar and the levator ani could be separated laterally. The puboperinealis muscle attached to part of the pubic symphysis behind the puboprostatic ligament and terminated at the perineal body. We were able to preserve the puboprostatic collar in all attempted cases. Furthermore, puboperineoplasty took 5min to complete. The total continence rate was 63.2% at median follow-up of 38.1 d. Immediate continence rate just after catheter removal was 42.1%. The rate at 1 and 4 wk was 52.6% and 71.4%, respectively. The margins of the examined specimens were all negative for malignancy. CONCLUSIONS: This modification should preserve or allow for early recovery of urinary continence from an anatomic perspective. Further studies are necessary to elucidate the clinical impact on a patient's early continence.

Adult↗
PubMed2006

Anatomy of right recurrent nerve node: why does early metastasis of esophageal cancer occur in it?

Early, distant and/or skip metastasis of squamous-cell thoracic esophageal cancer frequently occurs in the right recurrent nerve node (recR). However, the specific lymphatic route without a nodal relay, such as the submucosal ascending route, was not known for the recR afferent. Using 20 donated cadavers, macroscopic, and histological observations were performed on the recR and its surrounding lymphatics, especially afferent routes from the esophagus to the recR. Most afferent vessels of the recR originated from the right paratracheal node. However, the recR often (12/20) received a major submucosal lymphatic drainage route ascending along the thoracic esophagus. The submucosal vessel came out of the esophagus and ran in a longitudinal connective tissue mass along the right tracheo-esophageal groove. A direct drainage route was often (13/20) seen from the recR to the venous system. Moreover, because of the specific histology, collaterals seemed to be present around the recR. In the regional nodes of the intrathoracic esophagus, the recR histology was characterized by the high proportion of lymphocyte accumulating areas or the cortex. From the midthoracic level, metastatic cancer cells seemed to reach the recR via esophageal submucosal vessels in the early stage. Large lymphocyte accumulating areas of the recR suggested higher filtration capacity than other distal nodes. However, the collateral of the recR and its direct drainage to the venous system suggested that the recR involvement often corresponds to a systemic disease.

Afferent Pathways↗
PubMed2006

The effect of arm position on stretching of the supraspinatus, infraspinatus, and posterior portion of deltoid muscles: a cadaveric study.

BACKGROUND: The stretching of the supraspinatus and infraspinatus muscles is important to prevent shoulder injuries. Although several authors have advocated various stretching techniques, a general opinion has not been reached owing to the lack of quantitative analysis. METHODS: Nine fresh cadaveric shoulders were used to measure the strain on the supraspinatus, the middle and inferior portions of the infraspinatus, and the posterior portion of the deltoid muscles during eleven arm positions. The strain on the muscles was measured by precise displacement sensors attached to the center of each muscle belly. FINDINGS: In case of the supraspinatus muscle, abduction at extension showed significantly larger strain than that in the neutral position (P < 0.05). Internal rotation at extension showed significantly larger strain in the middle portions of the infraspinatus (P < 0.05). Internal rotation at 30 degrees and 60 degrees elevation as well as extension showed significantly larger strain in the inferior portion of the infraspinatus (P<0.05). Adduction at 60 degrees elevation did not show large strain in the infraspinatus muscle; however, significantly larger strain was observed in the posterior portion of the deltoid muscle. INTERPRETATION: Shoulder stretching techniques that are based on these experimental data can enhance the selective stretching of the corresponding muscles. Application of these techniques is considered to be useful for the prevention and treatment of shoulder injuries.

Aged↗
PubMed2006

Histological and morphometric study of the arterial route from the intercostal/lumbar artery via the Adamkiewicz artery to the anterior spinal artery using elderly cadavers with or without aortic aneurysms.

The Adamkiewicz artery originates from the lower intercostal/lumbar artery, runs along the vertebral roots of the spinal nerve, and communicates with the anterior spinal artery. In graft replacement for an aortic aneurysm, the lower intercostal/lumbar artery should be reconstructed to maintain the arterial blood supply to the lumbar spinal cord via the Adamkiewicz artery. To date, there are few reports on the histological characteristics of the arterial pathway from the aorta to the anterior spinal artery via the Adamkiewicz artery as well as the pathway in the Adamkiewicz artery. In addition, there is a possibility that this arterial pathway was degenerated by the aortic aneurysm. In this study, we attempted to reveal the histological characteristics of the arterial pathway by using elderly cadavers with or without unruptured aortic aneurysm. Specimens were obtained from 190 elderly cadavers (fixed in 10% formalin). These cadavers included 16 cases of aortic aneurysms. We collected fragments of the intercostal/lumbar artery, its dorsal branch, the Adamkiewicz artery, and the anterior spinal artery. After routine histological procedures, several staining procedures were performed for each section. A morphometric study was conducted at the light-microscopic level. The Adamkiewicz artery is composed of a thick intima that contains multiple thick elastic fiber layers and, probably, numerous intimal smooth muscle cells. Among the cadavers, the intimal thickness varied significantly in the intercostal/lumbar artery and the Adamkiewicz artery; it tended to be constant, irrespective of luminar dilatation in the Adamkiewicz artery, in contrast to other arteries. No significant difference was observed between the specimens with or without unruptured aortic aneurysms in all the parameters that were measured. The Adamkiewicz artery appeared to be capable of adapting to acute and chronic changes in systemic status that develop with aging because of its thick intima that contained numerous smooth muscles and elastic fibers. Against various events of systemic circulatory dysfunctions such as hypertension, its unique morphology suggested that this artery may play the critical role of a modulator, or even a barrier, that is intercalated along the arterial route to the lumbar cord.

Actins↗
PubMed2006

Operating behind Denonvilliers' fascia for reliable preservation of urogenital autonomic nerves in total mesorectal excision: a histologic study using cadaveric specimens, including a surgical experiment using fresh cadaveric models.

PURPOSE: Little is known about which urogenital nerves are liable to be injured along surgical planes in front of or behind Denonvilliers' fascia. METHODS AND RESULTS: Using semiserial histology for five fixed male pelves, we demonstrated that: 1) left/right communicating branches of bilateral pelvic plexuses run immediately in front of Denonvilliers' fascia; and 2) a lateral continuation of Denonvilliers' fascia separates the urogenital neurovascular bundle from the mesorectum. Notably, the mesorectum contains no or few extramural ganglion cells. At the level of the seminal vesicles, incision in front of Denonvilliers' fascia seems likely to injure superior parts of the pelvic plexus and the left/right communication. Moreover, at the prostate level, this incision misleads the surgical plane into the neurovascular bundle. Fresh cadaveric dissections of five unfixed male pelves confirmed that the surgical plane in front of Denonvilliers' fascia continues to a fascial space for the pelvic plexus containing ganglion cell clusters lateral and/or inferior to the seminal vesicles. CONCLUSIONS: To preserve all autonomic nerves for urogenital function, optimal total mesorectal excision for rectal cancer requires dissection behind Denonvilliers' fascia.

Aged↗
PubMed2006

Morphometrical study of arteries and veins in the human sheet-like muscles (pectoralis major, latissimus dorsi, gluteus maximus and trapezius) with special reference to a paradoxical venous merging pattern of the trapezius.

The trapezius is one of the critical targets of physical therapy for shoulder functional disorder because this muscle plays a great role in fixation and elevation of the shoulder. Trapezius (n = 63), latissimus dorsi (n = 5), pectoralis major (n = 7) and gluteus maximus (n = 7) muscles were obtained from 43 donated cadavers, and vascular morphologies were compared. An artery without a concomitant vein was found in 35 of 63 trapezius muscles. Moreover, twice as many venous merging sites as arterial branching sites were present in the trapezius. Notably, peripheral or distal venous tributaries were larger in caliber than the proximally located vein in 6.2% of all 404 venous merging sites in the trapezius. Moreover, similar paradoxical venous merging, in which tributaries were relatively thicker than drainage capacity of the venous trunk after merging according to Poisueille's law (peripheral or distal thickness >0.85 x proximal thickness), was observed in 39.1% (158 of 404 merging sites) in the trapezius, compared to 8-9% in the other 3 muscles. Given this vascular morphology, trapezius muscle seems likely to frequently display venous blood retention. Interestingly, venous valves were not observed in the trapezius, compared to 1-7 valves per one of the other 3 muscles. Abundant venous mergings without valves might form a venous network acting as a reservoir. Therefore, for the trapezius, collateral venous routes such as the external vertebral plexus are essential to provide additional peripheral drainage. However, sufficient muscle-pump function does not seem to be expected for trapezius muscle, given the venous courses parallel to muscle fibers.

Arteries↗
PubMed2006

The blood supply of the hilar bile duct and its relationship to the communicating arcade located between the right and left hepatic arteries.

BACKGROUND: There is an increasing demand for living donor liver transplants. However, the biliary complication rates are still high. METHODS: The anatomy of the communicating arcade (CA) between the right and left livers and its relevance to the blood supply of the hilar bile duct was evaluated using adult cadaveric livers and cast specimens. RESULTS: In all specimens that were of sufficient quality for evaluation, the CA was found to be located extrahepatically in the hilar plate with thin tributaries branching to the hilar bile duct. On the left side, 55% of the CA originated from a segment IV artery. On the right side, 73% of the CA originated from the right anterior hepatic artery. CONCLUSIONS: To maintain an adequate blood supply for the hilar bile duct of the donor graft during living donor liver transplantation, the branching point of the CA should be preserved.

Adult↗
PubMed2006

Role of cytochrome p450 in synaptocrinology: endogenous estrogen synthesis in the brain hippocampus.

In the hippocampus, the center for learning and memory, cytochrome P450s (P450scc, P450(17alpha), and P450arom) as well as 17beta-, 3beta-hydroxysteroid dehydrogenases, and 5alpha-reductase participate in the synthesis of brain steroids from endogenous cholesterol. These brain steroids include pregnenolone, dehydroepiandrosterone, testosterone, dihydrotestosterone, and 17beta-estradiol. Both estrogens and androgens are synthesized in the adult male hippocampal neurons. Although the expression levels of steroidogenic enzymes are as low as 1/200 to 1/50,000 of those in testis or ovary, the levels of synthesized steroids are sufficient for the local usage within small neurons (i.e., intracrine system). This intracrine system contrasts with the endocrine system in which high expression levels of steroidogenic enzymes are necessary in endocrine organs in order to supply steroids to many other organs via blood circulation. Endogenous synthesis of sex steroids in the hypothalamus is also discussed. Rapid modulation by estrogens and xenoestrogens is discussed concerning synaptic plasticity such as the long-term potentiation, the long-term depression, or spinogenesis. Synaptic expression of P450(17alpha), P450arom, and estrogen receptors suggests "synaptocrine" mechanisms of brain steroids, which are synthesized at synapses and act as synaptic modulators.

Animals↗
PubMed2006

Human situs inversus of the thoracoabdominal structures.

Situs inversus totalis is well known, but its comprehensive description has been rare, especially on the internal view of the heart. For discussions based on recent results in developmental biology, the present study demonstrates a region- or part-specific manner of the inverted morphology found in a male donated cadaver and discusses the pathogenetic mechanisms of situs inversus in the human. Therein, clearly inverted morphologies existed in the coronary vessels, the apex position (dextracardia), connections between the heart and great vessels, the internal view of the atrium, the aortic arch with the three major branches, lung and liver segments and abdominal gastrointestinal tract. However, the ventricular internal view suggested incomplete laterality, such as tricuspid atrioventricular valves for both ventricles. The cardiac conductive system appeared not to be inverted but abnormal. The thoracic aorta and pulmonary artery took an L-spiral position with modifications. The inferior vena cava was located on the right side of the abdominal aorta. However, the left-sided kidney was located superior to the right-sided kidney. Similarly, the testicular vessels did not exhibit a clearly inverted morphology, but were almost normal. Therefore, the posterior mediastinal and retroperitoneal structures appeared to exhibit neutral laterality, incomplete inverted morphology or even normal morphology. According to the personal history and present histology, this specimen was unlikely to correspond to Kartagener's syndrome. The present observations seem to be consistent with recent findings in mutant models of laterality disturbances, in which a single gene or molecule is responsible for the changes in a region-specific manner.

Aged↗
PubMed2006

Which morphology of dry bone articular surfaces suggests so-called fibrous ankylosis in the elderly human sacroiliac joint?

Usually, joint degeneration with aging results in articular cartilage defects, which results in bony ankylosis. However, the sacroiliac articular cartilage is maintained even in the elderly and the fibrous tissues make so-called 'fibrous ankylosis'. Macroscopically and histologically, we observed two sacroiliac joints obtained from one young cadaver as well as 23 sacroiliac joints from 23 elderly cadavers. Each joint was divided into two pieces along the long axis: one half was processed for routine histology after decalcification, whereas the other half was macerated to provide a dry bone specimen. The articular cartilage consistently contained abundant fibers and some of the fibers connected to tight intra-articular fiber bands. Fiber insertion into the thin subchondral bone displayed a tidemark in a spotty manner. Thus, the calcified fibrocartilage seemed to be present and seemed to provide fine granularity on the dry bone specimen. The joint cavity was sometimes closed with fibrocartilage-like tissues: we termed this complete fibrous ankylosis. The dry bone specimen corresponding to complete fibrous ankylosis exhibited significant microporosity and granularity because of fragmented subchondral bone. Moreover, bony ankylosis along the sacroiliac joint margin also contained fibrocartilage-like tissues. Therefore, complete fibrous ankylosis is also likely to be the preliminary step to bony ankylosis in the entire joint area. Consequently, microporosity with granularity seemed to be the most critical anthropological characteristic for estimation of sacroiliac joint movability.

Adult↗
PubMed2006

Types and frequencies of biliary tract variations associated with a major portal venous anomaly: analysis with multi-detector row CT cholangiography.

PURPOSE: To retrospectively determine whether major portal venous variation was more frequently associated with biliary variants, with consideration of the types and frequencies of biliary tract variations in the right and left liver lobes. MATERIALS AND METHODS: Before undergoing computed tomographic (CT) cholangiography, patients gave informed consent. The retrospective research protocol was approved, and informed consent was waived by the ethics committee. Forty-four patients aged 29-80 years who underwent multi-detector row CT cholangiography had a major portal vein variation in which the main portal vein diverged into the common trunk of the left portal vein and right anterior sectorial portal vein. One hundred fifty-eight consecutive patients aged 26-89 years who did not have this variation served as the control group. Three radiologists retrospectively evaluated the confluence pattern of the bile duct, the relationship between this pattern and the portal vein, and the major branching pattern of the portal vein. Pearson chi2 and Fisher exact tests were performed to identify significant differences between the two patient groups. RESULTS: The classic hilar confluence pattern, where the right posterior sectorial duct connects supraportally with the right anterior sectorial duct, was less frequent in the patients with the portal vein variation than in the control subjects (32% vs 73%, P < .05). The following biliary tract variations were identified more frequently in the variation group than in the control group (P < .05): right posterior sectorial duct joining left hepatic duct with a supraportal course (34% vs 12%), right posterior sectorial duct joining right anterior sectorial duct with an infraportal course (13% vs 4%), right posterior sectorial duct following an infraportal course (23% vs 8%), and left lateral segmental ducts caudal to the umbilical portion of the portal vein (14% vs 3%). The right hepatic duct, which receives all biliary ducts from the right lobe, was significantly less frequently developed in the variation group (46% vs 79%, P < .05). In addition, retroportal bile ducts were seen in four patients with the portal vein variation (P < .05). CONCLUSION: Bile duct configurations in patients with portal vein variation were significantly different from those in control subjects.

Adult↗