Добавил:
Sekretar
kiopkiopkiop18@yandex.ru
t.me/Prokururor I Вовсе не секретарь, но почту проверяю
Опубликованный материал нарушает ваши авторские права? Сообщите нам.
Вуз:
Предмет:
Файл:Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_5780_Библиотеки_им_академика_М_И_Перельмана.pdf
11.3 Circumscribed Changes
Schmidt, Ultrasound © 2007 Thieme
All rights reserved. Usage subject to terms and conditions of license.
ab
Fig. 453a, b Finding mimicking a tumor in the tail of the pancreas (T, cursor), CT
diagnosis. a Initial ultrasound scan shows a hypoechoic mass. b Fluid filling and
serial ultrasound: Intermittent normal appearance of the pancreatic tail (PT)
excludes a tumor and identifies the finding as transient fluid filling of the duodenojejunal flexure. AO = aorta, L = liver, S = stomach, SV = splenic vein
Differential Diagnosis of a Dilated Pancreatic Duct
..............................................................................................................
n
Postprandial dilatation (Fig. 454a)
n
Pancreas divisum (Fig. 454b):
x
Cutoff or stenosis of the pancreatic duct with no visible obstruction
x
Detection of two ducts in the pancreatic head
x
Enlargement of the pancreatic head
n
Chronic pancreatitis (Fig. 454c):
x
Undulating course of the duct
x
Calcifications, duct stones
x
Obstructive duct stone
n
Pancreatic tumor:
x
Tumor mass with prestenotic ductectasia
x
No duct tortuosity
x
No duct stones
n
Autoimmune chronic pancreatitis:
x
Circumscribed enlargement of the pancreas
x
Glandular atrophy
x
No evidence of an obstruction
n
Misinterpretation: The hepatic artery may be misidentified as a dilated pancreatic
duct (Fig.
454d).
11
11
11
Pancreas
Pancreas
Pancreas
309
11.3 Circumscribed Changes
Schmidt, Ultrasound © 2007 Thieme
All rights reserved. Usage subject to terms and conditions of license.
11
11
11
a
Pancreas
Pancreas
Pancreas
c
Fig. 454a–d Differential diagnosis of a dilated pancreatic duct. a Postprandial
dilatation (arrows). b Pancreas divisum: cutoff of the duct (arrows) at its junction
with a narrow accessory pancreatic duct. The main duct (arrow) is incompletely
formed. c Chronic pancreatitis with an obstructing duct stone and distal acoustic
shadow (S). d Splenic artery (SA), which can mimic a dilated duct in the B-mode
image. L = liver, SV = splenic vein, HA = hepatic artery, P = pancreas, DP, D =
pancreatic duct, VC = vena cava, AO = aorta
b
d
Further Testing
..............................................................................................................
n
In patients with suspected acute pancreatitis:
x
CT: If findings are equivocal (calcified cyst; internal densities due to clotting,
debris, or pus; suspected tumor), CT angiography should be used to differentiate between viable and nonviable tissue.
x
Fine-needle aspiration: of necrosis or hemorrhage for cytology and bacteriology,
for enzyme assays, and for the treatment of complicated cysts. In cases with
intra- and peripancreatic fluids (the most severe form of pancreatitis), sites
distant from the pancreas (omental bursa, hepatorenal and splenorenal recess,
cul-de-sac, mesentery) should also be sampled.
n
In patients with suspected chronic pancreatitis: Chronic pancreatitis with duct
stones or calcifications is difficult to diagnose with ultrasound, but it can be accurately diagnosed by a highly experienced sonographer. The only pitfall is coexisting carcinoma (in approximately 1–5 % of cases). Cases with persistent pain should
undergo operative treatment (a tumor in chronic pancreatitis often cannot be
detected by ultrasound, CT, or even at operation).
x
CT: indicated if ultrasound findings are equivocal (even with an experienced
sonographer) or if a tumor is suspected
x
Fine-needle aspiration: usually unrewarding as a method of tumor detection
310
11.3 Circumscribed Changes
Schmidt, Ultrasound © 2007 Thieme
All rights reserved. Usage subject to terms and conditions of license.
x
Tumor marker: elevated even in an acute inflammatory episode. Falling titers
make carcinoma less likely.
n
In patients with suspected pancreatic carcinoma: Ultrasound has an overall
accuracy rate of 72 % (comparable to CT), but considerably less with tumors I 3cm
x
Tumor marker: Ca 19–9 is positive in approximately 80 % of cases.
x
FNAB: only with an inoperable tumor (vascular infiltration, distant metastases;
ultrasound staging has high sensitivity, see Fig.
(unless there is concomitant chronic pancreatitis). FNAB may be omitted in
patients with a resectable tumor.
x
CT or endosonography : for evaluating tumor extent and operability. Endosonography has a 100 % accuracy rate in tumor diagnosis.
x
Operation: After the exclusion of inoperable tumors (approximately 80 %), the
latest results at large centers suggest that 30–45 % of tumors are resectable
even when locoregional metastasis has occurred. Size is not a measure of operability. The 5 year survival rate after an R0 resection and lymph node dissection
in patients with operable tumors is 10–35 %.
n
In patients with a suspected pancreatic pseudocyst:
x
Fine-needle aspiration of the cyst contents (bacteriology, amylase determination, cytology)
x
Further diagnostic criteria are given in Fig. 455.
73, p. 54). High accuracy rate
11
11
11
Pancreas
Pancreas
Pancreas
Fig. 455 Therapeutic algorithm for pancreatic pseudocysts (after Schwerk)
311
12.1 Examination
Schmidt, Ultrasound © 2007 Thieme
All rights reserved. Usage subject to terms and conditions of license.
12
12
12
12 Spleen
Spleen
Spleen
Spleen
12.1 Examination
Scan Planes
..............................................................................................................
n
Left subcostal oblique scan (see p. 27)
n
High left-sided flank scan (see p. 26)
Sonographic Anatomy and Normal Findings
..............................................................................................................
n
Sonographic anatomy (Fig. 456):
x
The spleen is a subphrenic organ located in the left side of the abdomen. Its
longitudinal axis is generally oriented parallel to the 10th rib.
x
The visceral surface of the spleen is closely related to the left kidney and
adrenal gland and to the tail of the pancreas.
x
The spleen has smooth borders but is frequently notched at the hilum (crenate
margin).
Fig. 456 Topographic anatomy
of the spleen
n
Normal findings (Fig. 457):
x
The normal spleen has a uniformly hypoechoic echo pattern.
x
The spleen is crescent- or wedge-shaped in longitudinal section and elliptical in
cross section (left subcostal scan, visible only in a magnified view).
n
Normal dimensions: length I 110 mm, thickness I 50 mm, width I 70 mm.
312
12.2 Sonographic Findings
Schmidt, Ultrasound © 2007 Thieme
All rights reserved. Usage subject to terms and conditions of license.
a b
Fig. 457a, b Sonographic appearance of the spleen (S) in longitudinal section
(high flank scan on the left side)
Scanning Protocol
..............................................................................................................
n
Place the transducer in the left axillary line between the inferior costal margin and
the iliac crest, parallel to the longitudinal course of the ribs.
n
By angling the probe slightly cephalad with the breath held at inspiration, it is
almost always possible to define the entire spleen.
n
Scanning tips :
x
If the patient inhales too deeply, the upper pole of the spleen is often obscured
by overlying air in the costophrenic angle.
x
If the organ is small or difficult to define, raising the patient’s left arm in the
supine or right lateral decubitus position and scanning at full inspiration will
open up the intercostal spaces and aid in visualizing the spleen.
12.2 Sonographic Findings
12
12
12
Spleen
Spleen
Spleen
Basic Principles
..............................................................................................................
n
Scanning the spleen is a routine part of the upper abdominal ultrasound study. The
spleen is often difficult to evaluate clinically because of its location, in which case
ultrasound is the standard method for the assessment of splenic size. The interpretation of B-mode findings is strongly dependent on clinical data. Besides the detection of focal abnormalities, follow-up scans are often needed to make a definitive
evaluation.
n
Classification:
x
Diffuse splenic changes (see p. 314): Reflected mainly in splenic enlargement
(splenomegaly). The following causes should be considered:
– Infectious diseases
– Systemic lymphatic diseases
– Myeloproliferative diseases
– Congestive splenomegaly (liver disease, venous congestion)
– Storage diseases
x
Focal splenic changes (see p. 315): On ultrasound these lesions may appear predominantly anechoic, predominantly hypoechoic, or predominantly echogenic.
– Overview: See Table
– Interpretive criteria: See Table
53.
54.
313
12.2 Sonographic Findings
Schmidt, Ultrasound © 2007 Thieme
All rights reserved. Usage subject to terms and conditions of license.
12
12
12
Table 53.Focal splenic changes
yyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy
Anechoic or hypoechoic Echogenic
Spleen
Spleen
Spleen
yyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy
Splenic cyst (p. 315)
Splenic abscess (p. 316) Splenic calcification (p. 319)
Splenic lymphoma (p. 316)
Splenic infarction (p. 317)
Splenic trauma (p. 317)
Splenic metastases (p. 318)
Table 54.Criteria for evaluating focal splenic lesions
yyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy
Criterion Description
yyyyyyyyyyyyyyyyyyyyyyyy
Echogenicity
Size Micronodular, macronodular (p. 316)
Margins Smooth, irregular (p. 315, 316)
Shape Round, oval, wedge-shaped, crescent-shaped (p. 317)
Internal echoes Mobile internal echoes on real-time observation (p. 318)
CDS Presence or absence of intralesional vascularity (p. 7)
Diffuse Changes
..............................................................................................................
n
Splenomegaly (Figs. 458 and 459): spleen i 12 cm in length q 5 cm in width.
x
Sonographic findings:
yyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy yyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy
Anechoic, hypoechoic (p. 315), echogenic (p. 318)
yyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy
Hemangioma, splenoma (p. 318)
– Diffuse changes usually have a homogeneous echo pattern
– Enlargement of the splenic poles
– Accentuation of the splenic vessels
x
Clinical findings : Often the clinical findings will suggest the correct diagnosis.
For example, infectious disease p inflammatory laboratory parameters and ser-
ologic findings; systemic lymphatic disease p generalized lymphadenopathy;
myeloproliferative syndromes p abnormal blood count and bone marrow findings; hemolytic anemia p laboratory hemolytic parameters; congestive spleno-
megaly p liver disease, portal hypertension, portosystemic collaterals, etc.
Fig. 458 Marked splenomegaly with
a homogeneous echo pattern of the
splenic parenchyma (S) in non-Hodgkin
lymphoma. The arrow points to an
accessory spleen. (NB: In this image
and the ones shown later in this chapter,
314
the transducer was rotated 180h)
12.2 Sonographic Findings
Schmidt, Ultrasound © 2007 Thieme
All rights reserved. Usage subject to terms and conditions of license.
Fig. 459 The size of the spleen
is determined by measuring its
greatest length (D1) and greate st
width (D2). (The third dimension,
depth, cannot be seen here.)
n
Small spleen (functional hypo-or asplenia): spleen I 7 cm in length q 3 cm in width
x
Sonographic findings:
– A small spleen will usually have a nonhomogeneous internal echo pattern
– Frequent nonvisualization of the splenic vessels
x
Clinical findings: differentiation from a physiologically small spleen due to
aging. More common in ulcerative colitis, sickle cell anemia, thorotrastosis,
immunologic diseases, and allogenic bone marrow transplantation
Focal Changes: Anechoic or Hypoechoic
..............................................................................................................
n
Splenic cyst (Figs. 460 and 461):
x
Sonographic criteria:
– Predominantly anechoic focus
– Variable size
– Smooth, round margins
12
12
12
Spleen
Spleen
Spleen
Fig. 460 Small, asymptomatic,
anechoic splenic cyst (Cy)
Fig. 461 Large anechoic cyst (Cy) with a
markedly thick wall, occupying almost
the entire spleen (S)
315
12.2 Sonographic Findings
Schmidt, Ultrasound © 2007 Thieme
All rights reserved. Usage subject to terms and conditions of license.
12
12
12
– Frequent peripheral calcification
– Occasional mobile internal echoes
– CDS: absence of vascularity
Spleen
Spleen
Spleen
x
Clinical findings: usually asymptomatic. Most primary cysts are congenital;
secondary cysts may result from antecedent trauma, infarction, pancreatitis,
or echinococciasis.
n
Splenic abscess :
x
Sonographic criteria:
– Predominantly hypoechoic focus
– Variable size
– Irregular margins, variable shape
– Occasional mixed echogenicity with air echoes and mobile internal echoes
– CDS: absence of vascularity
x
Clinical findings: Most patients are seriously ill, with pronounced signs of
inflammation. Microabscesses (Fig.
plenic candidiasis.
n
Splenic lymphoma (Fig. 463):
x
Sonographic criteria:
– Predominantly hypoechoic focus
– Variable size
– Smooth margins, often rounded
– Occasional diffuse nonhomogeneity
on real-time observation
462) most commonly result from hepatos-
Fig. 462 Multiple small, almost
anechoic microcysts (arrows) in
hepatosplenic candidiasis
abc
Fig. 463a–c Different patterns of splenic infiltration by malignant lymphoma.
a The entire spleen is diffusely permeated by very small, hypoechoic foci.
b Small hypoechoic foci, some with irregular margins. c Larger hypoechoic
316
lymphoma masses (L) occupying almost the entire spleen (S)
12.2 Sonographic Findings
Schmidt, Ultrasound © 2007 Thieme
All rights reserved. Usage subject to terms and conditions of license.
– CDS: vascularity
– Frequent splenomegaly
x
Clinical findings: Most patients have a known history of systematic lymphatic
disease (non-Hodgkin lymphoma, Hodgkin disease). Systemic manifestations
(fever, night sweats, weight loss), occasional LDH elevation
n
Splenic infarction (Fig. 464):
x
Sonographic criteria:
– Variable echogenicity, usually a hypoechoic focus
– Variable size; irregular margins, occasionally wedge-shaped
– Occasional free fluid in the abdomen
– Possible subcapsular hematoma
– CDS: absence of vascularity in the infarcted area
x
Clinical findings : Pain may be localized, diffuse, or absent. Splenic rub? Endocarditis? Sepsis? Myeloproliferative disease?
n
Splenic trauma (Figs. 465 and 466):
Fig. 464 Small, hypoechoic, wedgeshaped area of splenic infarction (Inf) in
a setting of myeloproliferative disease
x
Sonographic criteria:
– Predominantly hypoechoic focus; echogenic in the acute stage
– Variable size, irregular margins
– Occasional crescent-shaped subcapsular hematoma
– Occasional free fluid in the abdomen
– Liquid areas may contain mobile internal echoes
– CDS: absence of vascularity
12
12
12
Spleen
Spleen
Spleen
Fig. 465 Spontaneous subcapsular
hematoma formation (H) in a patient
with varicella sepsis. S = spleen
Fig. 466 Large posttraumatic intrasplenic hemorrhage (H), occupying almost
the entire spleen. AO = aorta
317
12.2 Sonographic Findings
Schmidt, Ultrasound © 2007 Thieme
All rights reserved. Usage subject to terms and conditions of license.
12
12
12
x
Clinical findings: history of trauma or underlying splenic disease (infection,
hematologic disease, congestive splenomegaly, splenic infarction, splenic
metastasis, etc.)
Spleen
Spleen
Spleen
n
Splenic metastases (Fig. 467):
x
Sonographic criteria:
– Predominantly hypoechoic focus, sometimes echogenic; occasional hypoe-
– Variable size and margins
– Occasional central necrosis
– CDS: vascularity
x
Clinical findings: Splenic metastases are rare and are usually due to hematogenous spread from an advanced malignancy. Direct infiltration of the spleen
(by gastric carcinoma, pancreatic carcinoma, etc., see Fig.
choic rim
468) is also rare.
Fig. 467 Solitary echogenic splenic
metastasis (arrows) with a peripheral
halo and central liquefaction in a
patient with colon carcinoma
Focal Changes: Echogenic
..............................................................................................................
n
Hemangioma, splenoma (Fig. 469): may resemble splenic metastases (Fig. 470),
littoral cell angioma, fresh hematoma, storage diseases, and hemangiosarcoma
x
Sonographic criteria:
– Predominantly echogenic focus
– Variable size
Fig. 468 Histologically confirmed gastric carcinoma. The tumor (TU) has
invaded the spleen (S) by contiguous
spread. ST = stomach, LU = lung
Fig. 469 Solitary echogenic mass,
detected incidentally in an asymptomatic patient. The mass remained
unchanged for 3 years, consistent with
318
a benign splenoma or hemangioma