Pier Lorenzo

Costa,

MD

Gabriella

Righetti,

#{149}

Air In the Main Demonstration

MD

Pancreatic with US’

I

Duct:

Air in the pancreas-nearly always related to an abscess or a pancreatic fistula-is rarely demonstrated. Over a 3-year period, the authors detected air in the main pancreatic duct with ultrasonography (US) in 11 patients.

modalities frequently demonstrate air in the bibiary tree in patients with spontaneous on sungicabby created biliary-enteric anastomo-

The ductal caliber was normal in five patients and dilated in six. At US, air

related

in the

main

terized

by

these conditions, two other cases of gas in the pancreatic duct have been reported: One patient had “innocent” gas in the main pancreatic duct, as demonstrated with computed tomography (CT) (2), while the other-who had undergone transampulbary septectomy-had air in the pancreatic duct demonstrated with ultrasound

pancreatic strongly

echogemc

lines

duct echogenic

in the duct,

is characfoci or

casting

acoustic shadows or producing reverberation artifacts. It is likely that in patients who have biliary-enteric anastomoses or have undergone sphincterotomy, air in the duct of Wirsung is the result of biliary-pan-

creatic refiux. not undergone likely

cause

In patients who have such operations, the of pancreatic gas is duo-

denal-pancreatic

duct

atic gas may be related other than a pancreatic it is therefore

fistula;

clinicians ductal

seen

secondary sphincter

on US images

to prior of Oddi

Pancre-

to causes abscess or

may be

surgery or due dysfunction.

ses (1). In contrast, is seldom demonstrated

(US)

to

pancreas is usually

on an enteric-

fistula.

In addition

to

(3).

of 11 patients,

to correlate

this

finding with previous surgery of the biiary-pancreatic system and with endoscopic retrograde cholangiopancreatography (ERCP), and to discuss the possible mechanisms by which gas enters the ious pathologic

duct of Wirsung conditions.

PATIENTS

AND

in van-

METHODS

1989,

October

air in the

observed

in

1986 and October

main

pancreatic

11 patients

(10

age

of 55.5 years

asymptomatic,

Seven

with

were

a mean

years). Conventional US examination was performed after an overnight fast and in the early morning,

(range,

was

without

any

27-73

special

Patients were imaged in the supine, right, and lateral decubitus positions high-resolution real-time instruments 920,

440,

Italy) nation From

the

Unit

of Ultrasonography,

Depart-

Medicine and Gastroenterology, G. B. Morgagni Hospital, FonlI, Italy. Received February 25, 1991; revision requested April 1; revision received July 1; accepted July 8. Address reprint requests to P.L.C., Via degli Orgogliosi 19, 47100 ForlI, Italy. 0

of Internal

RSNA,

1991

or 450; Esaote-Hitachi,

with a 3.5-MHz probe; was video recorded.

eight of the patients ERCP within 5 days

underwent after

upwith (AU

Genoa, each examiIn addition,

successful

sonography.

US

and

endoscopic

tab caliber,

measured

with

sonogra-

phy, was normal (within 2 mm) in five patients and enlarged in the remaining six (in two patients the ductab diameter

varied

during

the

exami-

nation, from 3 mm to 6-8 mm). In none of our patients was the presence of ductab gas an impediment to ductab caliber measurement, since no duct was

completely

filled

with

gas.

Nine

of the 11 patients underwent a second examination, and gas in the pancreatic duct was demonstrated again in only five. Sonographicalby, air in the main pancreatic duct was characterized by strongly echogenic foci on a noncontinuous echogenic line in the duct. These were irregularly distributed, always floated in the most anterion duct segments, cast acoustic shadon produced

(Fig

reverberation

1), and

patient’s

movement. 100 U of synthetic

un; Hoechst Germany) and caused Wirsung

duodenum

preparation.

and

findings are summarized in the Table. Pneumobilia was present in all the patients whose biliany system was operated on and absent in the other five. In four of the five patients who were not operated on, ERCP showed anatomic and/on inflammatory alterations of the papilla of Vater. Obviousby, gas in the duct of Wirsung was present in all of the patients. The duc-

artifacts

duct

one with acute pancreatitis). men and four were women,

ment

surgeries,

ows

Between 1991; 181:801-803

in the and

The purpose of this report is to describe the presence of gas in the pancreatic duct as detected with US in a

Index terms: Pancreas, abnormalities, 774.78 Pancreas, US studies, 774.12981 #{149} Pancreatic ducts, 774.78 Radiology

air

to an abscess

pseudocyst

series

important for that pancreatic

to realize gas

reflux.

MAGING

moved

with

the

In one patient, secretin (Sekneto-

AG, Frankfurt am Main, was intravenously injected dilatation of the duct of with expulsion of air into the (Fig 2).

DISCUSSION To our knowledge, no other series of patients with air in the pancreatic duct has been reported. The sonographic demonstration of gas in the

RESULTS The tories,

patients’ previous

principal clinical hisbiiary and pancreatic

Abbreviation: ERCP cholangiopancreatography.

=

endoscopic

retrograde

Clinical

an d Sonographic

Data Patient/

and Endoscopi

c Findings

Principal

Sex/Age

(y)

Clinical

1/F/57

Previous

History

Biliary colic, acute pancreatitis

Biliary/

Pancreatic

recurrent

US Findings

ERCP Findings

Pneumobilia; CHD = 6, W = 2; secretin test per-

Patent LLCJ; PDS at upper limits of normal, with delayed drainage of contrast

Surgery

C and LLCJ

formed

medium 2/M/38

Biliary

3/F/66

pancreatitis Biliary colic

4/M/51

Acute

5/M/73

None

colic, acute

alcoholic

recurrent

pancreatitis

C and LLCD

Pneumobilia; W = 5

CHD

=

13,

C and S

Pneumobilia;

CHD