Small Intestine

Добавил:

Sekretar kiopkiopkiop18@yandex.ru t.me/Prokururor I Вовсе не секретарь, но почту проверяю Опубликованный материал нарушает ваши авторские права? Сообщите нам.

Вуз:

Ростовский Государственный Медицинский Университет

Предмет:

Медицина общая

Файл:

Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_5780_Библиотеки_им_академика_М_И_Перельмана.pdf

Скачиваний:

Добавлен:

30.08.2026

Размер:

42 Мб

Скачать

☆

<<< < Предыдущая 25 26 27 28 29 30 31 32 33 34 35 36 3738 / 4938 39 40 41 42 43 44 45 46 47 48 49 > Следующая >>>

15.2 Stomach

Malignant gastric lymphoma: has the same appearance as diffuse lymphoma

(see above) or gastric carcinoma

Mesenchymal tumors: leiomyoma, neurinoma, gastrointestinal stromal tumors

(GIST)

Benign:

– I 6cm – No detectable vascularity

Malignant (Fig. 526a, b) : Leiomyosarcoma, GIST – Usually i 6cm – Tumor vascularity – Possible metastases

Fig. 526a, b a Flat, asymmetrical polypoid tumor (T) deeply invading and transgressin g the gastric wall: gastrointestinal stromal tumor (GIST), in this case malignant and already

metastasized. A = antrum. b Endoscopic appearance. Biopsies were negative

Luminal Widening or Narrowing

..............................................................................................................

Impaired gastric emptying due to bowel obstruction or diabetic gastroparesis :

Distended, fluid-filled stomach with no wall changes

Mechanical outflow obstruction:

Cicatricial stricture or inflammatory stenosis: no significant wall thickening

Tumor-related stenosis: significant concentric wall thickening (see Fig. 522, p. 357)

Evaluation and Further Testing

..............................................................................................................

Sonography: If the ultrasound beam is tangential to the gastric wall and encoun-

ters a series of multiple rugal folds, this may create the erroneous appearance of a thickened wall (Fig. missed, even in a patient with clinical manifestations (anorexia, weight loss, bloating, aversion to roasted foods), if all portions of the stomach are not visualized (left subcostal oblique scan to evaluate the body of the stomach, high paramedian longitudinal scan over the aortic hiatus to demonstrate the cardia and gastric inlet; see Fig.

524).

Gastroscopy with biopsies (may include loop biopsy) is indicated:

Whenever ultrasound detects wall thickening (e.g., in Ménétrier disease, chronic gastritis, carcinoma, lymphoma)

527). On the other hand, massive wall swelling may be

359

Gastrointestinal Tract

15.3 Small Intestine

Gastrointestinal Tract

Fig. 527 Multiple rugal folds can mimic wall thickening when they are tangential to the ultrasound beam

Even if findings suggest a benign tumor (smooth surface, marginal folds, folds lifted with a forceps for a submucosal lesion)

CT or endosonography: used for tumor staging or to evaluate tumor extent in

cases where ultrasound findings are equivocal. Locoregional metastases are generally detected at an early stage.

15.3 Small Intestine

Overview (Table 63):

..............................................................................................................

Table 63.Abnormal findings in the small intestine

yyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy

Functional disorders Thickening of the bowel

yyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy

(Gastro)enteritis Crohn disease of the

Sprue (p. 361) Acute febrile enteritis

Autonomic diabetic neuropathy (p. 361)

Partial or complete mechanical bowel obstruction (p. 361)

Intussusception (p. 362) Amyloidosis (p. 365)

Partial or complete paralytic ileus (p. 362)

wall

Long segmental thickening

terminal ileum (p. 363)

(p. 364)

Small bowel hematoma (p. 365)

Mesenteric vascular occlusion (p. 365)

yyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy

Circumscribed thickening

Benign tumors of the small intestine (adenoma, leiomyoma, p. 365)

Malignant tumors of the small intestine (duodenal carcinoma, carcinoid, p. 365)

360

15.3 Small Intestine

Functional Disorders

..............................................................................................................

(Gastro)enteritis (Fig. 528a):

Secretory fluid collection

Increased intraluminal bowel contents, may be anechoic to echogenic (depending on the contents)

Dilated bowel loops

Hyperperistalsis

Accentuated wall

Fig. 528a, b Functional disorders of the small intestine. a Acute enteritis : fluid-filled bowel loops (B). b Sprue: the “washing machine” sign

Sprue (Fig. 528b):

Hypoechoic wall thickening (edema)

Distention of the fluid-filled lumen

Real-time ultrasound: “washing machine” sign

Diabetic autonomic neuropathy (Fig. 529): common in patients with a i 8 year

history of diabetes, accompanied by other diabetic sequelae. Patients present clinically with refractory diarrhea and steatorrhea. Many cases show cardiopathy with tachycardia and peripheral neuropathies.

Distended bowel loops

Hypo- or hyperperistalsis

Partial or complete mechanical bowel obstruction : The bowel may be

obstructed by adhesions, a gallstone or foreign body, etc. (Figs. see also Figs. lated as a result of intussusception or volvulus.

110 and 111, p. 82, 83). The obstructed bowel may become strangu-

530 and 531;

Gastrointestinal Tract

Fig. 529 Diabetic autonomic neuropathic enteropathy: dilated loops of terminal ileum (TI) with hyperperistalsis and no wall thickening. The patient had a long clinical history of type II diabetes mellitus with recurrent diarrhea. AI = iliac artery

361

15.3 Small Intestine

Gastrointestinal Tract

Fig. 530a, b Partial or complete bowel obstruction. a Fluid-filled bowel loops with a “keyboard sign.” b “Stepladder sign ” of bowel obstruction

Fig. 531 Adhesive bowel obstruction: distended, fluid-filled terminal ileum. A keyboard or stepladder sign is not observed because of the absence of valvulae conniventes

Dilated bowel loops

Increased intraluminal fluid (anechoic to hyperechoic contents)

As a rule, peristalsis is initially increased but later is diminished or absent (bidirectional peristalsis)

“Keyboard sign” and “stepladder sign ” (fluid-outlined valvulae conniventes in the jejunum). The bowel loops have a keyboard-like appearance when imaged in longitudinal section and a stepladder-like appearance when imaged tangentially (Fig.

530). Valvulae conniventes are absent in the ileum, where the

dilated bowel loops present an essentially smooth inner surface (Fig.

Possible circumscribed free fluid

Obstruction by a gallstone or bezoar (Fig. 112, p. 83): signs of obstruction prox- imal to the stenosis. The obstructing object can be identified as an intraluminal mass (stone: typical stone features with distal shadowing; bezoar: nonshadowing hypoechoic mass)

Obstruction due to intussusception:

– The telescoped bowel segments appear as concentric outer and inner hypoe-

choic rings with a hyperechoic middle ring (“target-in-a-target” pattern;

common with polyps, tumors, and lymph nodes) – Slight wall thickening, possibly with a thin fluid rim – Absence of peristalsis in the intussusceptum

Partial or complete paralytic ileus (see Fig. 114, p. 84):

Caution: Paralytic ileus is frequently associated with peritonitis.

Dilated, atonic bowel loops crowded close together

Echogenic contents

Peristalsis is usually absent

Bowel wall layers are delineated

362

Possible circumscribed free fluid

531).

15.3 Small Intestine

Long Segmental Wall Thickening

..............................................................................................................

Crohn disease of the terminal ileum: –

Clinical features: diarrhea, pain in the right lower quadrant of the abdomen, elevated ESR; possible iron deficiency anemia, steatorrhea, vitamin B bile acid loss syndrome with chologenic diarrhea

Possible complications:

– Stenosis – Fistula formation: Fistulae may be enterocutaneous, enterovesical, entero-

mesenteric, or enterouterine

Caution: Fistulae may also occur with intestinal tumors.

– Hypoechoic inflammatory mesenteric reaction – Abscess formation – Bowel obstruction

Sonographic findings (Figs. 532–534): – Thickening of the terminal ileal wall to i 4 mm (for severity of inflamma-

tion, see Table – Increased intraluminal fluid with wall thickening (fluid due to decreased

absorption, unlike the secretory fluid collection in viral or bacterial enteritis) – Rigid bowel loop with absent or decreased peristalsis – Polypous inner wall with a “cobblestone” appearance

64)

deficiency,

Gastrointestinal Tract

Fig. 532a, b Crohn disease of the terminal ileum (TI), highly active form with stenosis. a B-mode image: very hypoechoic, swollen bowel walls (BW) with obliterated wall layers. CE = cecum. b CDS: marked inflammatory vascularity

Fig. 533a, b Crohn disease : markedly thickened wall of the terminal ileum (cursors) with an echogenic middle layer (isoechoic to submucosa) and luminal narrowing. a Lower abdominal longitudinal scan, b transverse scan. BW = bowel wall

363

15.3 Small Intestine

Gastrointestinal Tract

Fig. 534 Crohn disease of the terminal ileum: hypoechoic wall swelling (TI). Fistulous tracts (F), some terminating blindly, pass through the peritoneum (P) to the anterior abdominal wall (AW)

Table 64.Relationship of sonographic wall structure to the severity of

yyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy

Wall structure Degree of inflammation

yyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy

Accentuated

Echogenic layering with a broadened middle layer Moderate inflammation

Hypoechoic wall with obliterated layers Severe inflammation

inflammation in Crohn’s disease

yyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy

Mild inflammation

– Frequent accompanying mesenteritis – Signs of partial bowel obstruction – Possible free fluid, lymphadenopathy – CDS: color flow signals indicating inflammatory hyperperfusion (Fig.

Acute febrile enteritis (enterocolitis):

Clinical features: shows a predilection for the ileum but may also affect the jejunum. Acute right lower quadrant pain resembling appendicitis

Causative organisms: viruses (especially rotaviruses), Yersinia, Campylobacter, staphylococci, salmonellae (invasive microbial pathogens such as Shigella in the colon)

Sonographic criteria (Fig. 535; see also Fig. 544, p. 369): – Thickened wall with alternating hypoechoic, hyperechoic, and hypoechoic

layers; often shows “gyration” and concomitant involvement of the cecal pole – Local tenderness to bowel compression – Local free fluid

532b)

Fig. 535a, b Acute enteritis. a Swollen wall of the terminal ileum (cursors) with a distinct layered structure. b CDS: mesenteric lymph nodes (LN) anterior to the iliac artery and vein (A, V); mesenteric lymphadenitis

364

15.3 Small Intestine

– Frequent enlargement of mesenteric lymph nodes

(“mesenteric lymphadenitis”) – CDS: inflammatory hypervascularity

Small-bowel hematoma (Fig. 536): may result from anticoagulant medication or

a hemorrhagic diathesis

Thickened bowel walls

Pronounced, very hypoechoic wall swelling with luminal narrowing (“garden hose” appearance)

Fig. 536 Small-bowel hematoma in a patient on anticoagulant medication. Ultrasound shows intensely hypoechoic swelling of the bowel wall (BW)

Mesenteric vascular occlusion (see also Fig. 115, p. 85):

Hypoechoic “standing” small-bowel loop of variable length (hemorrhagic intestinal necrosis, superinfection)

Loss of layered wall structure

Signs of partial or complete bowel obstruction (see p. 353)

Doppler evidence of mesenteric vascular stenosis or occlusion

Amyloidosis: mild thickening involving a long segment of the bowel wall (intest-

inal amyloidosis may also occur without significant wall thickening)

Circumscribed Wall Thickening

..............................................................................................................

Benign tumors: Examples are adenoma, leiomyoma, and neurofibroma. Occasion-

ally the tumor can be directly visualized with ultrasound, based on the findings of contrast radiography.

Polypoid swelling of the bowel wall

Malignant tumors (Figs. 537 and 538) : Examples are duodenal carcinoma, small

bowel carcinoma, carcinoid, malignant lymphoma, and metastases

Gastrointestinal Tract

Fig. 537a, b Duodenal carcinoma. a Extensive tumor (T) with a prestenotic fluid collection. FL = fluid, LN = lymph node metastases. b Massive luminal widening of the duodenal bulb and antrum caused by the stenosis. PY = pylorus

365

15.4 Large Intestine

Gastrointestinal Tract

Fig. 538a, b Diffuse mesenteric metastases, CDS. a Metastatic carci-

noid: The metastasis (T) is infiltrating and destroying the superior mesenteric artery (SMA). b Diffuse mesenteric metastasis (T) with small-bowel wall thickening (BW) in a patient with rectal carcinoma. Cursors: normal wall thickness

Circumferential, infiltrative wall thickening with a target sign and clinical manifestations of stenosis

Detectable metastases may be present (Fig. 538)

Evaluation and Further Testing

..............................................................................................................

See p. 372.

15.4 Large Intestine

Overview (Table 65):

..............................................................................................................

Table 65.Abnormal findings in the large intestine

yyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy

Long segmental wall thickening Circumscribed wall thickening

yyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy

Crohn disease

Ulcerative colitis (p. 367) Polyps (p. 371)

Ischemic colitis (p. 368) Incarcerated epiploic appendix (p. 371)

Pseudomembranous (antibiotic-associated) colitis (p. 368)

Acute infectious colitis (p. 368) Carcinoid (p. 372)

Appendicitis (p. 369) Malignant lymphoma (p. 372)

Diverticulitis (p. 369)

Carcinoma (diffuse infiltration, p. 370)

Lymphoma (diffuse spread, p. 370)

yyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy yyyyyyyyy

Diverticula, diverticulitis (p. 371)

Colorectal carcinoma (p. 371)

Long Segmental Wall Thickening

..............................................................................................................

Crohn disease (Fig. 539): segmental involvement with a predilection for the

cecum. Up to 50 % of cases show colonic involvement. Only 25 % of patients have disease limited to the large intestine.

366

15.4 Large Intestine

Fig. 539a, b Crohn disease. a Of the terminal ileum (TI), here with preservation of the wall layers. b Of the cecum. CDS: hypoechoic polypoid swelling of the bowel wall (BW). Histology demonstrated high activity. CE = cecum

Sonographic findings are similar to those in Crohn disease of the terminal ileum (see p. 363).

Spread to the cecal pole is marked by a dilated, fluid-filled cecum. (Wall thickening can be detected and distinguished from fluid only by the sonographic observation of mobility and compression.)

Wall may show irregular swelling or polypoid changes, or it may be sharply delineated (accentuated).

Ulcerative colitis (Figs. 540 and 541): diffuse involvement with a predilection for

the rectum and the left half of the colon

Uniform wall thickening

Gastrointestinal Tract

Fig. 540 Ulcerative colitis without inflammatory activity : accentuated wall (BW, cursors). CDS does not show increased vascularity

Fig. 541a, b Ulcerative colitis, high activity. a B-mode image: thickened, layered wall and intraluminal fluid causing high-grade luminal narrowing. b CDS: Transverse scan shows marked inflammatory vascularity

367

15.4 Large Intestine

Acute exacerbation is marked by intensive wall thickening with a distinct layered structure (echogenic middle layer) and possible circumscribed free fluid

Ulcerative colitis of low activity or in remission: long segmental accentuation of the bowel wall

Ischemic colitis (Fig. 542):

Irregular hypoechoic wall thickening

Segmental involvement, usually affecting the left transverse and descending colon

Loss of anatomical wall layers (echogenicity of the layers may vary as a result of

Gastrointestinal Tract

frequent bacterial superinfection)

CDS: absence of color signals, or only peripheral vascularity

Fig. 542a, b Ischemic colitis (occlusion of the superior mesenteric artery, stenosis of the celiac trunk), CDS. a Sharply delineated starting point of the hypoechoic wall thickening (arrows). b Sharply delineated end point at the junction with the descending colon. Only peripheral vessels can be detected (arrow)

Pseudomembranous (antibiotic-associated) colitis (Fig. 543):

Extensive, occasionally grotesque wall thickening with luminal narrowing

Hypoechoic to heterogeneous echo pattern

Fig. 543 Severe pseudomembranous antibiotic-associated colitis: massive polypoid swelling of the bowel wall (BW) with luminal obliteration. Clinical picture of toxic megacolon

Acute infectious colitis (Fig. 544):

Accentuated wall thickening (high activity is marked by layered wall thickening with luminal narrowing and local free fluid)

Bowel dilatation due to increased fluid secretion

368

<<< < Предыдущая 25 26 27 28 29 30 31 32 33 34 35 36 3738 / 4938 39 40 41 42 43 44 45 46 47 48 49 > Следующая >>>

Соседние файлы в папке Библиотека им академика М.И. Перельмана

#
30.08.202653 Мб0Книга_5776_Библиотеки_им_академика_М_И_Перельмана.pdf
#
30.08.202651 Мб0Книга_5777_Библиотеки_им_академика_М_И_Перельмана.pdf
#
30.08.202648 Мб0Книга_5778_Библиотеки_им_академика_М_И_Перельмана.pdf
#
30.08.202642 Мб0Книга_5779_Библиотеки_им_академика_М_И_Перельмана.pdf
#
30.08.202678 Мб0Книга_578_Библиотеки_им_академика_М_И_Перельмана.pdf
#
30.08.202642 Мб0Книга_5780_Библиотеки_им_академика_М_И_Перельмана.pdf
#
30.08.202641 Мб0Книга_5781_Библиотеки_им_академика_М_И_Перельмана.pdf
#
31.08.202641 Мб0Книга_5782_Библиотеки_им_академика_М_И_Перельмана.pdf
#
31.08.202640 Мб0Книга_5783_Библиотеки_им_академика_М_И_Перельмана.pdf
#
31.08.202640 Мб0Книга_5784_Библиотеки_им_академика_М_И_Перельмана.pdf
#
31.08.202639 Мб0Книга_5785_Библиотеки_им_академика_М_И_Перельмана.djvu