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New Cholangiographic
Sign of Common
Opacification
of Intrahepatic
EDWARD
AND
B. BLACK1
JOSEPH
A previously undescrlbed sign of common bile duct obstructlon durIng intravenous cholangiography-Initial visualization of proximal intrahepatic ducts - was observed in 26 patients with surgically proven obstructive disease of the distal cornmon duct. In all cases, opacification of intrahepatic biliary radicles occurred on standard Interval films prior to visualIzation of the extrahepatic common bile duct, the reverse of the normal sequence. The abnormal opaclfication pattern reflects stasis of bile flow in the presence of distal obstruction and seems analogous to the urographic finding of opacified intrarenal calyces as the initial manifestation of distal ureteral
obstruction.
Recognition
gIographic opacificatlon layed films to confirm obstructIon.
of the alteration the
Bile Duct Obstruction:
sequence diagnosis
in the initial
Initial
Ducts
T. FERRUCCI,
JR.1
study. The preponderance of benign conditions in this probably reflects the tendency of malignant strictures
velop early high grade nous cholangiography.
obstruction,
obviating
fruitful
series to de-
intrave-
Preliminary observations of the dynamics of unimpeded biliany contrast excretion were accumulated from innumerable routine examinations considered normal radiographically. (Ap-
proximately 10 intravenous cholangiograms have been performed weekly in our department during the 5 year period of this
study.)
fication
cholan-
100
More
detailed
sequences
analysis
was carried
cholangiograms
of normal
in which
the
official
normal or negative. Excretion patterns basis of the 10, 20, and 30 mm plain
signals the need for deof a distal choledochal
and characterized
and scored
biliary
duct
out in a retrospective
as follows:
opaci-
series
interpretation
of was
were analyzed on the sequential radiographs (1) initial
simultaneous
opacification
of intrahepatic ducts and common bile duct; (2) initial opacification of common duct; and (3) initial opacification of intrahepatic ducts alone. Intravenous cholangiography was performed with the patient
Introduction
Little has been added to the radiographic criteria for the diagnosis of common bile duct obstruction by intravenous cholangiography since the initial comprehensive descriptions of the technique by Wise and co-workers [1-3]. Signs useful in the indirect diagnosis of common duct obstruction include dilatation and loss of the normal tapering of the duct, delayed common duct opacification, and an abnormal time/density of opacification relationship, with more intense opacification of the common duct at 120 mm than at 60 mm [1-3]. Direct diagnosis of common duct obstruction can be made only by demonstration of the obstructing entity (e.g., focal stnictune, intraluminal filling defect). This report draws attention to the dynamic patterns of biliary contrast flow during intravenous cholangiography and records a previously undescnibed cholangiographic sign of common duct obstruction-initial opacification of the intrahepatic biliary ducts. Subjects
and
in a supine
during
routine
intravenous
fusion
position
using
and at 10, 20, and 30 mm after
a mixture
of 100 ml of
infusion
was begun.
were obtained
Linear
at 30 mm,
Results
Contrasting were identified schematically Normal
initial biliany duct opacification sequences in normal and abnormal cases and are portrayed in figure 1.
Opacification
Patterns
Visualization of the unobstructed biliary tree was shown on interval plain films either as simultaneous opacification of intrahepatic radicles and the common duct proper (fig. 1A) or, with lesser degrees of contrast excretion, opacification of the common duct alone with delayed or negligible opacification of intrahepatic nadides (fig. 1B). Simultaneous opacification of both intrahepatic and common bile duct occurred with considerably greater frequency (72 of 100 cases) than opacification of the common duct alone (28 of 100). It is likely that the poorer opacification in the latter group reflected some cases with minor degrees of hepatic cellular dysfunction, thus decreasing biliary contrast excretion. It is also of note that both normal excretion sequences were occasionally observed in other patients with nonobstructive biliary duct disease, especially with small common duct calculi and low grade peniampullary stenosis.
Methods
cholangiographic
oblique
tomograms of the right upper quadrant and delayed films when indicated.
This study is based on a review of radiographs and hospital records of 26 patients demonstrating the cholangiographic sign of initial intrahepatic duct opacification. All cases were observed
right
meglumine iodipamide (Cholegrafin, Squibb), containing 5.1 g of iodine and 10.3 g of meglumine iodipamide, administered by slow intravenous infusion over a period of about 10 mm. Plain films of the right upper quadrant were obtained prior to the in-
examina-
tion over a 5 year period (1971-1976) at Massachusetts General Hospital. Each case had symptoms, signs, and laboratory findings suggesting common duct obstruction. Partial common duct obstruction, found at laparotomy in all cases, resulted from choledocholithiasis and/or benign strictures in 22 cases and from neoplasm in four. Numerous other patients with nonobstructing common duct calculi or low grade stenosis at the choledochoduodenal junction who did not show initial opacification of intrahepatic ducts were not included in the Received
April 21 , 1977; accepted after revision September 20, 1977. at the annual meeting of the American Roentgen Ray Society, Boston, September 1977. Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts J. T. Ferrucci, Jr. Presented ,
Am J Roentgenol
© 1978 American
130:61-65, January 1978 Roentgen Ray Society
61
021 14. Address
0361 -803X/78/01
reprint
00-0061
requests
$02.00
to
Downloaded from www.ajronline.org by 119.93.77.101 on 10/14/15 from IP address 119.93.77.101. Copyright ARRS. For personal use only; all rights reserved
62
BLACK
AND
FERRUCCI
Fig. 1 . opacification ducts
Patterns of biliary duct . Normal unobstructed show either simultaneous vi-
sualization
-
of
intrahepatic
radicles
and common bile duct (a) on opacification of the common duct alone (b). With obstructive biliary disease (C), visualization of slightly dilated intrahepatic radicles may precede or exceed degree of common duct filling, reversing normal sequence.
a
b NORMAL
Obstructive
Opacification
Patterns
When biliary obstruction was present and duct opacification was sufficient to yield diagnostic quality studies, a consistent alteration of the normal dynamics of contrast excretion was encountered. In these cases opacification of intrahepatic ducts occurred before visualization of the common bile duct, the reverse of the usual sequence (fig. 1C). In all 26 patients, intrahepatic duct opacification preceded or exceeded the degree of cornmon duct opacification and thus appeared early or isolated (figs. 2-4). This reversal of the normal opacification sequence did not occur in the normal sample group, nor was this encountered as a false positive effect during the period of the study. On the contrary, moderately high grade obstructive disease was invariably present when this sign was evident. Initial intrahepatic duct opacification was often appanent on the early plain film series but was frequently shown better with tomography. Although the time and density of detection of these intrahepatic nadicles varied with the degree of distal obstruction, they were often dilated with distention of secondand third-order branches. In several instances the increased volume of contrast medium within the smaller proximal ducts nendered them dramatically visible on plain films and initially gave the impression of an obstructing lesion at the level of the common hepatic duct or porta hepatis. However, in the majority of cases the significance of this altered opacification sequence was recognized as the study was carried out1 and appropriate delayed films were obtained
C ABNORMAL
to confirm tion.
the
presence
of distal
choledochal
obstnuc-
Discussion
The sole cholangiographic criterion of common duct obstruction based on functional considerations is the time-density retention concept advanced by Wise and co-workers 20 years ago [1-3]. That thesis held that increased contrast density within the common bile duct on a 2 hr film in reference to the density on a 1 hr film was indicative of partial obstruction of the common duct. The sign described here deals with the earlier stages of the examination-the intrahepatic ducts-and thereby extends the tenets of Wise and associates to patients with greater degrees of biliary obstruction. Initial visualization of the intrahepatic ducts is Undoubtedly related to stasis of the contrast agent associated with the increased intrabiliary pressure and decreased bile flow which accompany common duct obstruction [3-6]. The effect has a close analogy to intnavenous urography, where distal ureteral obstruction may be first manifested by the familiar initial opacification of a dilated intranenal collecting system with visualization of the remainder of the ureter to the site of distal obstruction. Both cases seem to be an expression of a more universal hydnodynamic phenomenon, namely, introduction of a low volume of contrast agent into a lange volume nonturbulent space. This results in nonmixing and accumulation in gravitationally dependent locations. Therefore, it is important to analyze not only the extrahepatic common duct during intravenous cholangiogna-
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NEW
SIGN
OF
BILE
DUCT
OBSTRUCTION
Fig. 2. -Isolated early intrahepatic duct opacification in distal common duct obstruction. A, Film at 10 mm showing intrahepatic radicles. B, Film at 45 mm disclosing faceted calculus obstructing distal common duct (arrow).
63
isolated
opacification
of dilated
Fig. 3. -Isolated intrahepatic duct opacification associated with calculus obstruction of biliary ducts in 59-year-old man with acute cholangitis. A, Film 30 mm after contrast infusion revealing opacification of bizarre intrahepatic duct structures containing lucent central defects. No common duct opacification is evident. B, Tomogram 3’/a hr after infusion disclosing marked diffuse duct dilatation and several intraluminal filling defects. At surgery, multiple common and intrahepatic duct calculi were found.
phy but, when common duct opacification is poor, to examine also the region of the liver itself for evidence of isolated small radicle opacification. When this appearance occurs, delayed serial filming is indicated for com-
plete evaluation of the extrahepatic biliary ducts. Awareness of this sign may prompt more careful scrutiny of cholangiognams with poor visualization in order to extract more subtle but still positive data.
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Fig. 4. -Early isolated intrahepatic duct visualization as sign of distal obstruction in 74-year-old woman with recurrent epigastnic pain, nausea, and vomiting. A, Plain film at 20 mm showing intrahepatic duct opacification without visualization of extrahepatic system. B, Tomogram at 30 mm showing marked dilatation of common duct with single large calculus in distal portion. At surgery, single 2.5 cm impacted calculus was found.
Fig.
5. -Transhepatic
obstructive with
jaundice
no opacification
showing
opacification
cholangiography.
1 1 days after Whipple distally.
Appearance
of markedly
dilated
Isolated
with distal common duct obstruction in 63-year-old man with film showing contrast confined to dilated intrahepatic radicles suggests peniportal block. Subcapsular contrast extravasation is evident medially. B, Delayed semierect film distal common duct. At surgery. iatrogenic ligature obstruction of distal common duct was found.
resection
opacification
of intrahepatic
for pancreatic
cancer.
radicles
A , Initial
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NEW
SIGN
OF
BILE
Similar alterations of contrast flow patterns in obstructive biliary disease have been noted during percutaneous transhepatic cholangiography [7, 8]. When high grade distal obstruction and elevated intraluminal pressures are present, contrast material deposited within intrahepatic ducts may appear stagnant and persist in the proximal duct system with little or no tendency to flow distally (fig. 5). Preliminary appearances after direct needle injection often simulate an obstruction in the proximal ducts and require delayed, prone, on semierect views to demonstrate the correct level and nature of the obstruction. Anatomically, it is also noteworthy that in this series duct opacification was most frequently and to a greater extent observed in the right hepatic duct and its branches. This is explained by the spatial arrangement of the intrahepatic ductal system [9]. With the patient in the customary supine or right posterior oblique position for intravenous cholangiography, the right hepatic duct and its branches are in a dependent position and will accumulate contrast material readily, while the left hepatic duct which courses ventrally is well drained by a gravitational effect. Thus gravity as well as elevated intraluminal pressures probably contribute to the prominent initial visualization of intrahepatic radicles in distal extrahepatic obstruction. Finally, since the wide range of diameters reported for unobstructed common ducts renders duct caliber an unreliable parameter of obstruction, identification of al-
DUCT
65
OBSTRUCTION
tered dynamics of biliary ualization of intrahepatic tional dynamic radiographic
contrast excretion initial visducts-affords a useful addisign of duct disease. -
REFERENCES RE: Intravenous Cholangiography. Springfield, III., Thomas, 1962 Wise RE, Johnston DO, Salzman FA: The intravenous cholangiographic diagnosis of partial obstruction of the common bile duct. Radiology 68 : 507-525, 1957 Wise RE, O’Brien AG: Interpretation of the intravenous cholangiogram.JAMA 160:819-827, 1956 Hopton D, White U: An evaluation of manometnic operative cholangiography in 100 patients with biliary disease. Surg Gynecol Obstet 1 33 : 949-954, 1971 Hopton D, White U: Radiomanometry, flow rates, and cholangiognaphy in the evaluation of common bile duct disease.AmJSurg 123:73-79, 1972 Burgener FA, Fischer HW, Adams JT: Intravenous cholangiography in different degrees of common bile duct obstnuction. An experimental study in the dog. Invest Radio!
1 . Wise
2.
3. 4.
5.
6.
7.
10:342-350, 1975 Ferrucci JT Jr, Wittenbeng
J: Refinements
in Chiba
needle
transhepatic cholangiography. Am J Roentgenol 129:1116, 1977 8. Kittredge AD, Baer JW: Percutaneous transhepatic cholangiography: problems in interpretation. Am J Roentgenol 125:35-46,
1975
9. Stern WZ, Schein CJ, Jacobson HG: The significance of the lateral view in T-tube cholangiography. Am J Roentgenol
87:764-771,1961
New Cholangiographic
Sign of Common
Opacification
of Intrahepatic
EDWARD
AND
B. BLACK1
JOSEPH
A previously undescrlbed sign of common bile duct obstructlon durIng intravenous cholangiography-Initial visualization of proximal intrahepatic ducts - was observed in 26 patients with surgically proven obstructive disease of the distal cornmon duct. In all cases, opacification of intrahepatic biliary radicles occurred on standard Interval films prior to visualIzation of the extrahepatic common bile duct, the reverse of the normal sequence. The abnormal opaclfication pattern reflects stasis of bile flow in the presence of distal obstruction and seems analogous to the urographic finding of opacified intrarenal calyces as the initial manifestation of distal ureteral
obstruction.
Recognition
gIographic opacificatlon layed films to confirm obstructIon.
of the alteration the
Bile Duct Obstruction:
sequence diagnosis
in the initial
Initial
Ducts
T. FERRUCCI,
JR.1
study. The preponderance of benign conditions in this probably reflects the tendency of malignant strictures
velop early high grade nous cholangiography.
obstruction,
obviating
fruitful
series to de-
intrave-
Preliminary observations of the dynamics of unimpeded biliany contrast excretion were accumulated from innumerable routine examinations considered normal radiographically. (Ap-
proximately 10 intravenous cholangiograms have been performed weekly in our department during the 5 year period of this
study.)
fication
cholan-
100
More
detailed
sequences
analysis
was carried
cholangiograms
of normal
in which
the
official
normal or negative. Excretion patterns basis of the 10, 20, and 30 mm plain
signals the need for deof a distal choledochal
and characterized
and scored
biliary
duct
out in a retrospective
as follows:
opaci-
series
interpretation
of was
were analyzed on the sequential radiographs (1) initial
simultaneous
opacification
of intrahepatic ducts and common bile duct; (2) initial opacification of common duct; and (3) initial opacification of intrahepatic ducts alone. Intravenous cholangiography was performed with the patient
Introduction
Little has been added to the radiographic criteria for the diagnosis of common bile duct obstruction by intravenous cholangiography since the initial comprehensive descriptions of the technique by Wise and co-workers [1-3]. Signs useful in the indirect diagnosis of common duct obstruction include dilatation and loss of the normal tapering of the duct, delayed common duct opacification, and an abnormal time/density of opacification relationship, with more intense opacification of the common duct at 120 mm than at 60 mm [1-3]. Direct diagnosis of common duct obstruction can be made only by demonstration of the obstructing entity (e.g., focal stnictune, intraluminal filling defect). This report draws attention to the dynamic patterns of biliary contrast flow during intravenous cholangiography and records a previously undescnibed cholangiographic sign of common duct obstruction-initial opacification of the intrahepatic biliary ducts. Subjects
and
in a supine
during
routine
intravenous
fusion
position
using
and at 10, 20, and 30 mm after
a mixture
of 100 ml of
infusion
was begun.
were obtained
Linear
at 30 mm,
Results
Contrasting were identified schematically Normal
initial biliany duct opacification sequences in normal and abnormal cases and are portrayed in figure 1.
Opacification
Patterns
Visualization of the unobstructed biliary tree was shown on interval plain films either as simultaneous opacification of intrahepatic radicles and the common duct proper (fig. 1A) or, with lesser degrees of contrast excretion, opacification of the common duct alone with delayed or negligible opacification of intrahepatic nadides (fig. 1B). Simultaneous opacification of both intrahepatic and common bile duct occurred with considerably greater frequency (72 of 100 cases) than opacification of the common duct alone (28 of 100). It is likely that the poorer opacification in the latter group reflected some cases with minor degrees of hepatic cellular dysfunction, thus decreasing biliary contrast excretion. It is also of note that both normal excretion sequences were occasionally observed in other patients with nonobstructive biliary duct disease, especially with small common duct calculi and low grade peniampullary stenosis.
Methods
cholangiographic
oblique
tomograms of the right upper quadrant and delayed films when indicated.
This study is based on a review of radiographs and hospital records of 26 patients demonstrating the cholangiographic sign of initial intrahepatic duct opacification. All cases were observed
right
meglumine iodipamide (Cholegrafin, Squibb), containing 5.1 g of iodine and 10.3 g of meglumine iodipamide, administered by slow intravenous infusion over a period of about 10 mm. Plain films of the right upper quadrant were obtained prior to the in-
examina-
tion over a 5 year period (1971-1976) at Massachusetts General Hospital. Each case had symptoms, signs, and laboratory findings suggesting common duct obstruction. Partial common duct obstruction, found at laparotomy in all cases, resulted from choledocholithiasis and/or benign strictures in 22 cases and from neoplasm in four. Numerous other patients with nonobstructing common duct calculi or low grade stenosis at the choledochoduodenal junction who did not show initial opacification of intrahepatic ducts were not included in the Received
April 21 , 1977; accepted after revision September 20, 1977. at the annual meeting of the American Roentgen Ray Society, Boston, September 1977. Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts J. T. Ferrucci, Jr. Presented ,
Am J Roentgenol
© 1978 American
130:61-65, January 1978 Roentgen Ray Society
61
021 14. Address
0361 -803X/78/01
reprint
00-0061
requests
$02.00
to
Downloaded from www.ajronline.org by 119.93.77.101 on 10/14/15 from IP address 119.93.77.101. Copyright ARRS. For personal use only; all rights reserved
62
BLACK
AND
FERRUCCI
Fig. 1 . opacification ducts
Patterns of biliary duct . Normal unobstructed show either simultaneous vi-
sualization
-
of
intrahepatic
radicles
and common bile duct (a) on opacification of the common duct alone (b). With obstructive biliary disease (C), visualization of slightly dilated intrahepatic radicles may precede or exceed degree of common duct filling, reversing normal sequence.
a
b NORMAL
Obstructive
Opacification
Patterns
When biliary obstruction was present and duct opacification was sufficient to yield diagnostic quality studies, a consistent alteration of the normal dynamics of contrast excretion was encountered. In these cases opacification of intrahepatic ducts occurred before visualization of the common bile duct, the reverse of the usual sequence (fig. 1C). In all 26 patients, intrahepatic duct opacification preceded or exceeded the degree of cornmon duct opacification and thus appeared early or isolated (figs. 2-4). This reversal of the normal opacification sequence did not occur in the normal sample group, nor was this encountered as a false positive effect during the period of the study. On the contrary, moderately high grade obstructive disease was invariably present when this sign was evident. Initial intrahepatic duct opacification was often appanent on the early plain film series but was frequently shown better with tomography. Although the time and density of detection of these intrahepatic nadicles varied with the degree of distal obstruction, they were often dilated with distention of secondand third-order branches. In several instances the increased volume of contrast medium within the smaller proximal ducts nendered them dramatically visible on plain films and initially gave the impression of an obstructing lesion at the level of the common hepatic duct or porta hepatis. However, in the majority of cases the significance of this altered opacification sequence was recognized as the study was carried out1 and appropriate delayed films were obtained
C ABNORMAL
to confirm tion.
the
presence
of distal
choledochal
obstnuc-
Discussion
The sole cholangiographic criterion of common duct obstruction based on functional considerations is the time-density retention concept advanced by Wise and co-workers 20 years ago [1-3]. That thesis held that increased contrast density within the common bile duct on a 2 hr film in reference to the density on a 1 hr film was indicative of partial obstruction of the common duct. The sign described here deals with the earlier stages of the examination-the intrahepatic ducts-and thereby extends the tenets of Wise and associates to patients with greater degrees of biliary obstruction. Initial visualization of the intrahepatic ducts is Undoubtedly related to stasis of the contrast agent associated with the increased intrabiliary pressure and decreased bile flow which accompany common duct obstruction [3-6]. The effect has a close analogy to intnavenous urography, where distal ureteral obstruction may be first manifested by the familiar initial opacification of a dilated intranenal collecting system with visualization of the remainder of the ureter to the site of distal obstruction. Both cases seem to be an expression of a more universal hydnodynamic phenomenon, namely, introduction of a low volume of contrast agent into a lange volume nonturbulent space. This results in nonmixing and accumulation in gravitationally dependent locations. Therefore, it is important to analyze not only the extrahepatic common duct during intravenous cholangiogna-
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NEW
SIGN
OF
BILE
DUCT
OBSTRUCTION
Fig. 2. -Isolated early intrahepatic duct opacification in distal common duct obstruction. A, Film at 10 mm showing intrahepatic radicles. B, Film at 45 mm disclosing faceted calculus obstructing distal common duct (arrow).
63
isolated
opacification
of dilated
Fig. 3. -Isolated intrahepatic duct opacification associated with calculus obstruction of biliary ducts in 59-year-old man with acute cholangitis. A, Film 30 mm after contrast infusion revealing opacification of bizarre intrahepatic duct structures containing lucent central defects. No common duct opacification is evident. B, Tomogram 3’/a hr after infusion disclosing marked diffuse duct dilatation and several intraluminal filling defects. At surgery, multiple common and intrahepatic duct calculi were found.
phy but, when common duct opacification is poor, to examine also the region of the liver itself for evidence of isolated small radicle opacification. When this appearance occurs, delayed serial filming is indicated for com-
plete evaluation of the extrahepatic biliary ducts. Awareness of this sign may prompt more careful scrutiny of cholangiognams with poor visualization in order to extract more subtle but still positive data.
Downloaded from www.ajronline.org by 119.93.77.101 on 10/14/15 from IP address 119.93.77.101. Copyright ARRS. For personal use only; all rights reserved
Fig. 4. -Early isolated intrahepatic duct visualization as sign of distal obstruction in 74-year-old woman with recurrent epigastnic pain, nausea, and vomiting. A, Plain film at 20 mm showing intrahepatic duct opacification without visualization of extrahepatic system. B, Tomogram at 30 mm showing marked dilatation of common duct with single large calculus in distal portion. At surgery, single 2.5 cm impacted calculus was found.
Fig.
5. -Transhepatic
obstructive with
jaundice
no opacification
showing
opacification
cholangiography.
1 1 days after Whipple distally.
Appearance
of markedly
dilated
Isolated
with distal common duct obstruction in 63-year-old man with film showing contrast confined to dilated intrahepatic radicles suggests peniportal block. Subcapsular contrast extravasation is evident medially. B, Delayed semierect film distal common duct. At surgery. iatrogenic ligature obstruction of distal common duct was found.
resection
opacification
of intrahepatic
for pancreatic
cancer.
radicles
A , Initial
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NEW
SIGN
OF
BILE
Similar alterations of contrast flow patterns in obstructive biliary disease have been noted during percutaneous transhepatic cholangiography [7, 8]. When high grade distal obstruction and elevated intraluminal pressures are present, contrast material deposited within intrahepatic ducts may appear stagnant and persist in the proximal duct system with little or no tendency to flow distally (fig. 5). Preliminary appearances after direct needle injection often simulate an obstruction in the proximal ducts and require delayed, prone, on semierect views to demonstrate the correct level and nature of the obstruction. Anatomically, it is also noteworthy that in this series duct opacification was most frequently and to a greater extent observed in the right hepatic duct and its branches. This is explained by the spatial arrangement of the intrahepatic ductal system [9]. With the patient in the customary supine or right posterior oblique position for intravenous cholangiography, the right hepatic duct and its branches are in a dependent position and will accumulate contrast material readily, while the left hepatic duct which courses ventrally is well drained by a gravitational effect. Thus gravity as well as elevated intraluminal pressures probably contribute to the prominent initial visualization of intrahepatic radicles in distal extrahepatic obstruction. Finally, since the wide range of diameters reported for unobstructed common ducts renders duct caliber an unreliable parameter of obstruction, identification of al-
DUCT
65
OBSTRUCTION
tered dynamics of biliary ualization of intrahepatic tional dynamic radiographic
contrast excretion initial visducts-affords a useful addisign of duct disease. -
REFERENCES RE: Intravenous Cholangiography. Springfield, III., Thomas, 1962 Wise RE, Johnston DO, Salzman FA: The intravenous cholangiographic diagnosis of partial obstruction of the common bile duct. Radiology 68 : 507-525, 1957 Wise RE, O’Brien AG: Interpretation of the intravenous cholangiogram.JAMA 160:819-827, 1956 Hopton D, White U: An evaluation of manometnic operative cholangiography in 100 patients with biliary disease. Surg Gynecol Obstet 1 33 : 949-954, 1971 Hopton D, White U: Radiomanometry, flow rates, and cholangiognaphy in the evaluation of common bile duct disease.AmJSurg 123:73-79, 1972 Burgener FA, Fischer HW, Adams JT: Intravenous cholangiography in different degrees of common bile duct obstnuction. An experimental study in the dog. Invest Radio!
1 . Wise
2.
3. 4.
5.
6.
7.
10:342-350, 1975 Ferrucci JT Jr, Wittenbeng
J: Refinements
in Chiba
needle
transhepatic cholangiography. Am J Roentgenol 129:1116, 1977 8. Kittredge AD, Baer JW: Percutaneous transhepatic cholangiography: problems in interpretation. Am J Roentgenol 125:35-46,
1975
9. Stern WZ, Schein CJ, Jacobson HG: The significance of the lateral view in T-tube cholangiography. Am J Roentgenol
87:764-771,1961
