Will tetrahydrocannabinol be formed from cannabidiol in gastric fluid? An in vivo experiment

Cannabidiol (CBD) products have ascribed an uprising trend for their health-promoting effects worldwide. In contrast to Δ⁹-tetrahydrocannabinol (THC), CBD exhibits no state of euphoria. Since conversion of CBD into THC in an acidic environment has been reported, it has not been proved whether this degradation will also occur in human gastric fluid. A total of 9 subjects ingested 400 mg CBD as a water-soluble liquid together with lecithin as an emulsifier and ethanol as a solubilizer. Blood samples were taken up to 4 h, and urine samples were submitted up to 48 h. THC, 11-hydroxy-Δ⁹-THC (THC-OH), 11-nor-9-carboxy-Δ⁹-THC (THC-COOH), CBD, 7-hydroxy cannabidiol (7-OH-CBD), and 7-carboxy cannabidiol (7-CBD-COOH) were determined in blood and THC-COOH and 7-CBD-COOH in urine by LC–MS/MS. Neither THC, THC-OH, nor THC-COOH were detectable in any serum specimen. Only two urine samples revealed THC-COOH values slightly above the threshold of 10 ng/ml, which could also be caused by trace amounts of THC being present in the CBD liquid. It can be concluded that negative consequences for participants of a drug testing program due to a conversion of CBD into THC in human gastric fluid appear unlikely, especially considering a single intake of dosages of less than 400 mg. Nevertheless, there is a reasonable risk for consumers of CBD products being tested positive for THC or THC metabolites. However, this is probably not caused by CBD cyclization into THC in human gastric fluid but is most likely due to THC being present as an impurity of CBD products.

     

Frequency of common bile duct motion artifacts caused by inferior vena cava pulsation on magnetic resonance cholangiopancreatography.

PURPOSE: We assessed the frequency of common bile duct (CBD) motion artifacts caused by inferior vena cava (IVC) pulsation on magnetic resonance cholangiopancreatography (MRCP). METHODS: We retrospectively evaluated CBD motion artifacts in 4 MRCP sequences from each of 115 consecutive patients. RESULTS: We observed 37 (32.2%) ghost artifacts at the ventral and dorsal aspects of the CBD on transaxial, half-Fourier acquisition single-shot turbo spin-echo (HASTE-ax) images; no such artifacts were observed on transaxial T(2)-weighted turbo spin-echo images. In 10 patients, we observed 9 (7.8%) pseudo-defects of the CBD on 3-dimensional T(2)-weighted turbo spin-echo with navigator-triggered prospective acquisition correction technique MRCP and 6 (5.2%) pseudo-defects on single-shot rapid acquisition with relaxation enhancement MRCP. Pseudo-defects were significantly more frequent in patients with ghost artifacts than without (9 of 37 [24.3%] versus one of 78 [1.3%]; P<0.01, McNemar test). CONCLUSION: Although uncommon, pseudo-defects of the CBD caused by IVC pulsation are observed on MRCP. MRCP interpretation that includes comparison with HASTE-ax images can diminish the potential misinterpretation of such CBD motion artifact as bile duct tumor or biliary stone.     

Differential inhibition of human cytochrome P450 2A6 and 2B6 by major phytocannabinoids

Inhibitory effects of Δ⁹-tetrahydrocannabinol (Δ⁹-THC), cannabidiol (CBD), and cannabinol (CBN) on the catalytic activities of human recombinant cytochrome P450 (CYP) 2A6 and CYP2B6 were investigated. Δ⁹-THC, CBD, and CBN noncompetitively inhibited coumarin 7-hydroxylase activity of recombinant CYP2A6 with the apparent K _i values of 28.9, 55.0, and 39.8 μM, respectively. On the other hand, Δ⁹-THC, CBD, and CBN inhibited 7-benzoxyresorufin O-debenzylase activity of recombinant CYP2B6 in a mixed fashion with the K _i values of 2.81, 0.694, and 2.55 μM, respectively. Because the inhibition of CYP2B6 by CBD was the most potent, investigation was conducted to determine which moiety of the CBD structure was responsible for the inhibition. Olivetol and d-limonene, the partial structure of CBD, inhibited the CYP2B6 activity to some extent. Inhibitory effects of CBD-2′-monomethyl ether and CBD-2′,6′-dimethyl ether attenuated with the number of methylations on the phenolic hydroxyl groups in the resorcinol moiety of CBD. Cannabidivarin, a CBD analogue having a propyl side chain, inhibited the CYP2B6 activity less potently than CBD possessing a pentyl side chain. Therefore, both structures of pentylresorcinol and terpene moieties of CBD were suggested to play important roles in the CYP2B6 inhibition. Δ⁹-THC, CBD, and CBN showed metabolism-dependent inhibition for CYP2A6 but not for CYP2B6. Furthermore, Δ⁹-THC and CBN were characterized as mechanism-based inhibitors for CYP2A6. The k _inact and K _I values of Δ⁹-THC were 0.0169 min⁻¹ and 0.862 μM, respectively; the k _inact and K _I values of CBN were 0.00909 min⁻¹ and 1.01 μM, respectively. These results indicated that Δ⁹-THC, CBD, and CBN showed differential inhibition against CYP2A6 and CYP2B6.     

Urinary cannabinoid levels during nabiximols (Sativex<Superscript>®</Superscript>)-medicated inpatient cannabis withdrawal

Nabiximols (Sativex^®) is a buccal spray containing both ?⁹-tetrahydrocannabinol (THC) and cannabidiol (CBD). It has shown promise as an agonist substitution therapy for treating cannabis withdrawal and dependence. Monitoring urinary cannabinoid levels during treatment is important for determination of cannabinoid pharmacokinetics and for treatment adherence during clinical trials. Here, we use a recently described hydrolysis method to liberate urinary CBD from its glucuronide conjugate, and describe the trajectory of urinary CBD, THC, 11-nor-9-carboxy-THC (THC-COOH), and 11-hydroxy-THC (11-OH-THC) in patients receiving nabiximols treatment (or placebo) during cannabis withdrawal. Urine and plasma samples were taken before and during a 6-day inpatient treatment regime and during a 3-day drug-free washout. Urine was hydrolysed with red abalone β-glucuronidase, and CBD, THC, THC-COOH, and 11-OH-THC were quantified in daily urine using liquid chromatography-tandem mass spectrometry. Overall, urine and plasma cannabinoid levels followed similar trajectories and closely reflected the dosing schedule. During nabiximols treatment, CBD levels in urine and plasma rose markedly, while concentrations of THC and its metabolites remained at, or slightly above, pre-treatment levels. Following hydrolysis, urinary CBD was detected at levels 50 and 200 times as high as those in non-hydrolysed plasma and non-hydrolysed urine, respectively. THC, THC-COOH, and 11-OH-THC concentrations were also amplified by urinary hydrolysis. This method allows sensitive assessment of urinary CBD, and may prove useful in clinical studies involving nabiximols or other cannabinoid therapies.     

胆汁流动伪影的MR胆胰管成像表现

目的：探讨MR胆胰管成像(MRCP)上胆汁流动伪影的影像表现。方法 回顾性分析85例胆总管正常和95例胆总管扩张患者的MRCP资料,在MRCP原始薄层图像上观察记录胆汁流动伪影的表现,采用x2检验对各组胆汁流动伪影的发生率进行比较,采用Spearman等级相关分析检验胆总管直径和伪影表现形式的关系。结果 胆总管正常组流动伪影发生率38.8％ (33/85),扩张组流动伪影发牛率83.2％( 79/95),差异有统计学意义(x2 ＝37.512,P＝0.000)。胆总管直径(ψ)≤4mm时无流动伪影,4 mm ＜ψ≤8 mm时,流动伪影主要表现为单线征(52.6％,30/57)。胆总管轻度扩张时,流动伪影主要表现为三线征(85.7％,36/42);中度扩张时主要表现为多线征(84.6％,22/26),各组间表现差异有统计学意义(x2＝284.561,P＝0.000)。随胆总管直径增加,伪影的表现形式不同,二者有相关性(r ＝0.553,P＝0.000)。结论 胆总管正常组可以发生流动伪影;胆总管扩张组流动伪影发生率高于正常组;胆汁流动伪影的表现形式与胆总管直径有相关性。     

Diameters of the common bile duct in adults and postcholecystectomy patients: a study with 64-slice CT

This study aims to collect data by multidetector computed tomography (MDCT) on the diameter of the normal common bile duct (CBD) and the diameter of CBD after cholecystectomy. In this retrospective study, CBD measurements were performed on axial oblique images, perpendicular to the long axis of the distal CBD. The mean diameter of the normal CBD was measured in 604 patients without cholecystectomy. The patients were divided into 6 groups according to their age. Analysis of variance (ANOVA) was used to compare data obtained from the six age groups. The mean diameter of the CBD of 46 patients who had cholecystectomy was calculated. The results were compared with age matched control group by Student's t test. The largest diameter of CBD ranged from 1.8 to 11.8mm. The mean of the largest diameter of 604 subjects was 4.77 ± 1.81. The diameter of the CBD significantly increased with age. Mean largest CBD diameters of postcholecystectomy subjects (7.28 ± 2.37) were significantly greater than age matched control group. In conclusion the diameter of CBD shows a considerable increase with age. The largest diameter of the CBD is up to 6mm in most of the subjects. An upper limit of 8mm appears reasonable after the age of 50; and an upper limit of 10mm seems appropriate for cholescystectomized subjects.     

Reduced cardiac uptake and enhanced washout of 123I-MIBG in pure autonomic failure occurs conjointly with Parkinson's disease and dementia with Lewy bodies.

The purpose of this study was to investigate myocardial uptake of 123I-metaiodobenzylguanidine (MIBG) in patients with pure autonomic failure (PAF), which has pathologic features in common with idiopathic Parkinson's disease (IPD) and dementia with Lewy bodies (DLB). METHODS: Six patients with PAF, 130 with IPD, 21 with DLB, 9 with corticobasal degeneration (CBD), 11 with progressive supranuclear palsy (PSP), and 11 with multiple-system atrophy (MSA) underwent myocardial 123I-MIBG scintigraphy, as did 16 control patients. RESULTS: Resulting heart-to-mediastinum (H/M) ratios were significantly lower in patients with PAF, IPD, or DLB than in patients with CBD, PSP, or MSA and in the controls. H/M ratios were lower for delayed images than for early ones in patients with PAF, IPD, or DLB, whereas the ratios were higher for delayed images in patients with CBD and in the controls. CONCLUSION: Cardiac sympathetic denervation and enhanced washout of 123I-MIBG from sympathetic nerve terminals may develop in parallel in patients with PAF, IPD, or DLB.     

Reflux sign in cholescintigraphy after administration of a gallbladder contracting agent

This study reviewed 12 patients with the reflux sign in cholescintigraphy to assess its diagnostic usefulness in evaluating biliary passage. The reflux sign was determined by appearance or increase of the radioactivity in peripheral intrahepatic bile ducts after intramuscular injection of 10 micrograms of ceruletide diethylamine (caerulein). Of the 12 patients, there were common bile duct (CBD) stone in four, chronic pancreatitis in two, biliary dyskinesia in two, papillary adenoma of the CBD, dilated CBD, papillitis, and juxtapapillary duodenal diverticulum in one each. Cholangiographically, dilated caliber of the CBD more than or equal to 12 mm was found in five and equivocal caliber of 8 to 11 mm was in the remaining seven. Apparent stenosis of the CBD was found in four with dilated CBD. There were two patients who had CBD stone with equivocal caliber of the CBD. The reflux sign seems to be a sensitive finding indicating the presence of biliary dysfunction, and would be helpful for the detection of incomplete obstruction of the CBD or CBD stone, especially in a patient with equivocal caliber of the CBD.     

∆9-Tetrahydrocannabinol,a major marijuana component,enhances the anesthetic effect of pentobarbital through the CB1 receptor

Purpose

?⁹-Tetrahydrocannabinol (?⁹-THC) and cannabidiol (CBD), major psychoactive constituents of marijuana, induce potentiation of pentobarbital-induced sleep in mice. We have elucidated the mechanism of enhancement of the anesthetic effect of pentobarbital by cannabinoids.

Methods

We carried out pharmacological experiment and cannabinoid₁ (CB₁) receptor binding assay using CB₁ antagonists to clarify whether the CB₁ receptor is involved in the synergism or not. The affinities of cannabinoids for the CB₁ receptor in the mouse brain synaptic membrane were evaluated using a specific CB₁ ligand, [³H]CP55940.

Results

Although the potentiating effect of ?⁹-THC on pentobarbital-induced sleep was attenuated by co-administration of CB₁ receptor antagonists, such as SR141716A and AM251, at a dose of 2 mg/kg, intravenously (i.v.) to mice, the CBD-enhanced pentobarbital-induced sleep was not inhibited by SR141716A. The inhibitory constant (Ki) values of ?⁹-THC and CBD were 6.62 and 2010 nM, respectively, showing a high affinity of ?⁹-THC and a low affinity of CBD for the CB₁ receptor, respectively. A high concentration of pentobarbital (1 mM) did not affect specific [³H]CP55940 binding on the mouse brain synaptic membrane.

Conclusions

These results suggest that binding of ?⁹-THC to the CB₁ receptor is involved in the synergism with pentobarbital, and that potentiating effect of CBD with pentobarbital may differ from that of ?⁹-THC. We successfully demonstrated that ?⁹-THC enhanced the anesthetic effect of pentobarbital through the CB₁ receptor.

     

Differentiating malignant from benign common bile duct stricture with multiphasic helical CT

PURPOSE: To evaluate retrospectively the use of multiphasic helical computed tomography (CT) to differentiate malignant and benign common bile duct (CBD) strictures in patients with only a focal CBD stricture and to determine predictors for this differentiation. MATERIALS AND METHODS: Institutional review board approval and informed patient consent were not required. Fifty patients (35 men, 15 women; age range, 35-87 years; mean age, 61.6 years) with only a focal CBD stricture comprised the sample for this study (32 malignant and 18 benign strictures). The diagnosis of all malignant and five benign CBD strictures was confirmed by reviewing patients' surgical and pathology records; in 13 benign CBD strictures, the diagnosis was confirmed by means of clinical features. Multiphasic CT findings were analyzed with regard to the wall thickness, location, length, and enhancement pattern of the involved CBD, the upstream CBD diameter, and other findings. CT features to identify benign and malignant CBD strictures were compared by means of univariate analysis and multivariable stepwise logistic regression analysis. RESULTS: Malignant strictures were longer (17.9 mm +/- 6.6 [+/- standard deviation]) than benign strictures (8.9 mm +/- 6.8) (P < .0001), and upstream CBD diameters were larger in malignant cases (22.0 mm +/- 5.4) than in benign cases (17.8 mm +/- 4.6) (P = .033). The involved wall thickness was more than 1.5 mm in 26 malignant cases and three benign cases (P < .0001). During both hepatic arterial and portal venous phases, greater enhancement than that in the normal CBD were more frequently observed in malignant cases (in 27 and 30 patients for hepatic arterial and portal venous phase scans, respectively) than in benign cases (in two and three patients, respectively) (P < .0001). Results of multivariable stepwise logistic regression analysis showed that hyperenhancement of the involved CBD during the portal venous phase was the only variable that could be used to independently differentiate malignant from benign strictures. CONCLUSION: Hyperenhancement of the involved CBD during the portal venous phase is the main factor distinguishing malignant from benign CBD strictures.     

Evaluation of cortical atrophy between progressive supranuclear palsy and corticobasal degeneration by hemispheric surface display of MR images

BACKGROUND AND PURPOSE: Three-dimensional imaging and hemispheric volumetry are useful for the assessment of degenerative cortical atrophy. Our purpose was to determine the features of cortical atrophy in progressive supranuclear palsy (PSP) and corticobasal degeneration (CBD) by means of a hemispheric surface display generated with MR images. METHODS: The extent of cortical atrophy was evaluated with automated MR hemispheric surface display and volumetry in 19 patients with PSP and 19 with CBD. RESULTS: Most cortical regions were less atrophic in PSP than in CBD. The parietal lobe, paracentral regions, anterior middle frontal lobe, and posterior inferior frontal lobe were significantly more atrophic in CBD than in PSP, whereas the brainstem was significantly more atrophic in PSP. The mean hemisphere-to-intracranial volume ratio was significantly greater in patients with PSP (74.5%) than in those with CBD (71.4%), whereas the mean brainstem-to-intracranial volume ratio was significantly smaller in PSP (1.4%) than in CBD (1.6%). Asymmetry of hemispheric volume was significantly larger in the CBD group than in the PSP group. CONCLUSION: Hemispheric surface display and volumetry are generally helpful and especially useful for the differentiation of PSP and CBD.     

The width of the common bile duct in relation to age and stone disease. An ultrasonographic study

The common bile duct (CBD) was measured in 600 ultrasound studies. In normal patients the mean width of the CBD increased from 2.8 mm in the age group 20 years or younger to 4.1 mm in patients 71 years of age or older. The mean width of the CBD for all age groups in normal cases was 3.4 (range 2 to 11 mm). In presence of cholelithiasis the mean width of the CBD was 4.5 mm (range 2 to 15 mm). There was no further increase of the CBD after cholecystectomy (mean width 4.6 mm, range 2 to 12 mm). The CBD in patients with hepatocellular disease was wider than normals (mean 4.4 mm) and markedly increased in patients with pancreatic disease (mean 6.2 mm, range 2 to 21 mm) due to obstruction in several cases.     

Common bile duct stones: reassessment of criteria for CT diagnosis

To evaluate the specificity of previously suggested computed tomographic (CT) criteria for diagnosing common bile duct (CBD) stones, CT scans of 38 patients with CBD stones were compared with scans of 32 patients with carcinoma obstructing the CBD and 28 nonobstructed patients. The CBD stone was directly visualized as a target sign or densely calcified structure in 29 of 38 patients with stones (76%); one with carcinoma showed a similar target sign. A rim of increased density in the distal CBD was found without accompanying target sign in six patients with stones (16%), compared with 12 with carcinoma (38%) and 15 nonobstructed patients (54%). Irregular intraluminal densities without a detectable target sign were noted in four patients with stones (11%), compared with eight with carcinoma (25%) and nine nonobstructed patients (32%). Abrupt termination of the CBD without a mass was more common as an isolated finding in patients with carcinoma (31%) than in patients with stones (13%). CT is accurate in detecting CBD stones in certain patient populations, but direct visualization of the stone is required.     

Common bile duct diameter in an asymptomatic population: A magnetic resonance imaging study

AIM: To measure the common bile duct (CBD) diameter by magnetic resonance cholangiopancreatography (MRCP) in a large asymptomatic population and analyze its some affecting factors.METHODS: This study included 862 asymptomatic subjects who underwent MRCP. The CBD diameter was measured at its widest visible portion on regular end-expiration MRCP for all subjects. Among these 862 subjects, 221 volunteers also underwent end-inspiration MRCP to study the effect of respiration on the CBD diameter. The age, sex, respiration, body length, body weight, body mass index (BMI), portal vein diameter (PVD), length of the extrahepatic duct and CBD, cystic junction radial orientation and location were recorded. The subjects were divided into 7 groups according to age. All of the above factors were compared with the CBD diameter on end-expiration MRCP.RESULTS: Among the 862 subjects, the CBD diameter was 4.13 ± 1.11 mm (range, 1.76-9.45 mm) and was correlated with age (r = 0.484; P < 0.05), with a dilation of 0.033 mm per year. The upper limit of the 95% reference range was 5.95 mm, resulting in a reasonable upper limit of 6 mm for the asymptomatic population. Respiration and other factors, including sex, body length, body weight, BMI, PVD, length of the extrahepatic duct and CBD, cystic junction radial orientation and location, were not related to the CBD diameter.CONCLUSION: We established a reference range for the CBD diameter on MRCP for an asymptomatic population. The CBD diameter is correlated with age. Respiration did not affect the non-dilated CBD diameter.     

Primary Malt Lymphoma of the Common Bile Duct

Primary mucosa-associated lymphoid tissue (MALT) lymphoma arising in the common bile duct (CBD) is extremely rare. In our case of MALT lymphoma, CT and MRI showed long, segmental, irregular wall thickening of the CBD and minimal dilatation of the upstream bile duct. A preoperative diagnosis of cholangiocarcinoma was made, but histologic evaluation confirmed MALT lymphoma of the CBD. We herein present a rare case of MALT lymphoma of the CBD with CT and MRI findings.     

Imaging early-stage corticobasal degeneration with [99mTc]TRODAT-1 SPET

AIM: The aim of this study was to investigate the nigrostriatal dopaminergic function in patients with corticobasal degeneration (CBD) using [2-[[2-[[[3-(4-chlorophenyl)-8-methyl-8-azabicyclo[3.2.1]oct-2-yl]methyl](2-mercaptoethyl)amino]ethyl]amino]ethanethiolato(3-)-N2,N2',S2,S2']oxo-[1R-(exo-exo)]-[99mTc]technetium ([99mTc]TRODAT-1) brain single-photon emission tomography (SPET). METHODS: Five patients with probable CBD, 10 age- and duration-matched patients with idiopathic Parkinson's disease (IPD) and 10 age-matched healthy volunteers completed the SPET study. The images were obtained 4 h after intravenous injection of 925 MBq of [99mTc]TRODAT-1. Using a magnetic resonance imaging atlas of the striatum, the ratios of specific striatal binding to non-specific occipital binding were calculated. RESULTS: Clinical analysis showed that the CBD patients obtained significantly higher scores on the Unified Parkinson's Disease Rating Scale and a significantly worse score for activities of daily living. In the CBD and IPD groups, striatum-occipital/occipital, caudate nucleus-occipital/occipital and putamen-occipital/occipital ratios decreased significantly relative to those of healthy subjects. No statistical difference could be found between the CBD and IPD groups for these ratios, although relatively even, decreased uptakes in the caudate nucleus and putamen were found in the CBD group. On further analysis of the index of binding reduction, the differences between the caudate nucleus and putamen were significantly lower in the CBD group than in the IPD group. The striatal uptake of [99mTc]TRODAT-1 showed a distinct asymmetry in both the CBD and IPD patients. CONCLUSION: From this study, it can be concluded that early-stage CBD patients have a worse performance and more difficulties with daily activities than IPD patients. CBD patients demonstrated essentially similar patterns of [99mTc]TRODAT-1 binding as those with IPD. However, there was relatively more homogeneous involvement of the caudate nucleus and putamen in the CBD patients. This provides information about the differences between these patients in the early stages.     

Dynamic test in the echographic evaluation of the common bile duct

Common bile duct (CBD) diameter was measured with ultrasonography in 396 patients (131 had previous cholecystectomy) before and 40 minutes after the ingestion of a fatty meal. CBD diameter reduced in 177 cases, remained unchanged in 175, increased in 44. The increasing of CBD diameter always means obstructive choledochal pathology, caused by stones or other pathologic conditions. Caliber reduction or other pathologic conditions. Caliber reduction is physiologic. When CBD remains unchanged, in 10% of the cases there are stones in the duct.     

Detection of common bile duct stones by hepatobiliary scintigraphy

Hepatobiliary scintigraphy and direct X-ray cholangiography were compared in 29 patients with common bile duct (CBD) stones confirmed at surgery. The scintigraphic findings included no visualization of the biliary system (NV), pooling of bile in the biliary system (PB), prolonged transit time over 60 min (PTT), filling defect in the CBD image (FD), and reflux of bile toward the intrahepatic ducts after gallbladder stimulation (RB). The positive rates of NV, PB, PTT, FD, and RB in patients with CBD stones were 7%, 31%, 17%, 48%, and 14%, respectively. One or more of these five findings was found in 83%. Although the NV was a useful finding suggesting complete obstruction of the CBD, it shared little in the diagnosis of CBD stone. The positive rate of the PB was relatively high and it would be a useful finding as an indication of the presence of passage disturbance of the CBD. The PB was usually accompanied by the FD. The PTT had some usefulness in the detection of incomplete obstruction of the CBD in patients with a visualized gallbladder. In patients with no visualization of the gallbladder, however, the transit time tended to be shorter than that of gallbladder visualized patients. Therefore, the judgment of PTT in patients with no visualized gallbladder needed another criteria. The FD was the most frequent among the five findings and the sites of FD correlated well with CBD stones on direct X-ray cholangiography. The FD would be a reliable finding indicating CBD stone or CBD stenosis. Although the RB was a finding limited in patients with a visualized gallbladder, it seemed to be a helpful findings for the detection of CBD stone in patients with a mildly dilated CBD.     

Asymmetrical cerebral perfusion demonstrated by noninvasive arterial spin-labeling perfusion imaging in a patient with corticobasal degeneration

This is to report arterial spin-labeling (ASL) regional cerebral blood flow (rCBF) mapping findings in a case of corticobasal degeneration (CBD). A 68-year-old man gradually developed limb-kinetic apraxia, myoclonus, and rigidity in the left hand and was diagnosed as having CBD. Magnetic resonance imaging and single photon emission computed tomography revealed atrophy and decreased blood flow, respectively, in the right hemisphere, findings that were compatible with CBD. In addition, ASL rCBF mapping demonstrated asymmetrical hypoperfusion areas in locations typical for CBD, proving its potential usefulness for routine clinical differential diagnosis.     

Diagnostic value of the reflux sign in cholescintigraphy after administration of a gallbladder contracting agent--a comparison with X-ray cholangiography

This study reviewed 25 patients with the reflux sign in cholescintigraphy to assess its diagnostic value in evaluating biliary passage. After at least 4-hour fasting 5 mCi of 99mTcPMT or p-butyl IDA was injected intravenously and serial images were recorded before and after intramuscular injection of 10 micrograms of ceruletide diethylamine (caerulein). The reflux sign was determined positive when increased radioactivities in the left hepatic duct (minor reflux; MIR) or more peripheral intrahepatic ducts (major reflux; MAR) were recognized after injection of caerulein. The reflux sign was found in 28 of 237 (12%) studies. Direct and/or indirect X-ray cholangiograms were available in 25 (MIR; 15, MAR; 10). They included common bile duct (CBD) stone in 4, dilated CBD in 4, biliary dyskinesia (BD) in 4, chronic pancreatitis (CP) in 4, gallbladder (GB) stone in 3, duodenal ulcer (DU) in 2, CBD adenoma, pancreatic pseudocyst (PP), duodenal diverticle (DD), and acute cholangitis (AC) in 1 each. Their serum bilirubin levels were within normal limit in all but 2 at the time of cholescintigraphy. Transit time of radionuclides to the duodenum was found prolonged more than 60 min in 17 (68%) patients and persistent pooling in the CBD was found in 8 (28%) patients on scintigrams. The diameter of the CBD on X-ray cholangiogram was ranged 4 to 17 mm. Dilated CBD of more than 10 mm was found in 13 (52%) patients and apparent stenosis of the CBD in 6 (24%) patients. MAR seemed to correspond to increased diameter of the common hepatic more than 2 mm after caerulein injection in DIC. No abnormal findings in X-ray cholangiography was found in 10 (40%) patients including 3 with BD, 2 with GB stone, 2 with DU, 1 each with CP, PP, and AC. All those patients demonstrated MIR. We concluded that major reflux (MAR) sign was helpful in detecting an incomplete obstruction of the CBD, especially in patients with slightly to mildly dilated CBD.