Splenic Trauma

Published on 20/07/2015 by admin

Filed under Radiology

Last modified 22/04/2025

Print this page

rate 1 star rate 2 star rate 3 star rate 4 star rate 5 star
Your rating: none, Average: 3 (1 votes)

This article have been viewed 4226 times

 Perisplenic hematoma: Located adjacent to spleen and implies disruption or rupture of splenic capsule

image Intraparenchymal hematoma: Typically round or irregular in shape
image Subcapsular hematoma: Constrained by splenic capsule and crescentic in shape
• Sentinel clot sign: Highest density blood localizes adjacent to spleen (or any site of injury)

image Indicates splenic injury even without demonstrable laceration
• Parenchymal laceration: Irregular linear, branching, or stellate area of nonenhancing low attenuation
• Splenic fracture: Deep laceration extending from outer capsule through splenic hilum
• Splenic infarction: Unusual (< 2% of cases) in the setting of trauma, and can be segmental or complete
• Active arterial extravasation: High-attenuation focus isodense with aorta, surrounded by lower attenuation clot or hematoma

image Distinction between active extravasation and pseudoaneurysm using delayed phase images

TOP DIFFERENTIAL DIAGNOSES

• Splenic cleft
• Splenic abscess
• Splenic infarct
• Splenic cyst
• Lymphoma and splenic tumors

CLINICAL ISSUES

• Most commonly injured solid abdominal organ in blunt trauma and most common abdominal organ injury requiring surgery
• Prone to develop delayed hemorrhage, but excellent prognosis with early intervention (surgery/embolization)
• Identification of active arterial extravasation or pseudoaneurysm best predictor of need for surgery and failure of nonoperative management
image
(Left) Axial CECT in an 87-year-old woman who fell at a nursing home demonstrates a splenic parenchymal laceration image and intraperitoneal blood image, as well as a lentiform heterogeneous and higher attenuation collection flattening the normal convex lateral splenic contour, representing a subcapsular hematoma image.

image
(Right) Axial CECT in a 23-year-old man injured in a motor vehicle accident shows a shattered spleen with a sentinel clot image in the perisplenic region and large hemoperitoneum image.
image
(Left) Axial CECT in a 19-year-old man who was an unrestrained passenger in a motor vehicle accident shows marked upper abdominal hemoperitoneum image, a shattered spleen with intrasplenic high-attenuation pseudoaneurysms image, and a focus of active arterial extravasation lateral to the spleen within the peritoneal cavity image.

image
(Right) Axial CECT in the same patient shows the active arterial extravasation image extending into the left paracolic gutter with surrounding hemoperitoneum image.

TERMINOLOGY

Synonyms

• Splenic laceration or splenic fracture

Definitions

• Splenic parenchymal injury ± capsule disruption

IMAGING

General Features

• Best diagnostic clue

image Low-attenuation splenic laceration with high-density active bleeding
• Morphology

image Lacerations: Linear or jagged edges
image Fracture: Laceration extending from outer cortex to hilum
image Subcapsular hematoma: Flattened contour of splenic parenchyma

Radiographic Findings

• Radiography

image Abdominal radiography

– Left upper quadrant soft tissue mass
– Signs of intraperitoneal fluid with widening of distance between flank strip and descending colon
– Fluid in pelvis with prominent pelvic “dog ears”
image Chest radiography demonstrates associated injuries

– Lower left lobe atelectasis &/or consolidation
– Left rib fractures, pneumothorax, pleural effusion

CT Findings

• NECT

image High-attenuation hemoperitoneum > 30 HU or perisplenic clot > 45 HU

– Perisplenic, intraparenchymal, or subcapsular hematoma

image Perisplenic hematoma: Located adjacent to spleen and implies disruption or rupture of splenic capsule
image Intraparenchymal hematoma: Typically round, ovoid, or irregular in shape
image Subcapsular hematoma: Constrained by splenic capsule; crescentic in shape and compresses lateral margin of parenchyma
image Sentinel clot sign: Highest density blood localizes adjacent to spleen (or any site of injury)

– Indicates splenic injury even in absence of demonstrable laceration
image Layered or lamellated clot if bleeding is intermittent
• CECT

image Parenchymal laceration: Irregular linear, branching, or stellate area of nonenhancing low attenuation within parenchyma

– May extend to splenic capsule resulting in capsular tear
– Should become less conspicuous on follow-up imaging
image Splenic fracture: Deep laceration extending from outer capsule through splenic hilum
image Splenic infarction: Unusual (< 2% of cases) in setting of trauma

– Can be segmental or complete
– Wedge-shaped area of hypoattenuation
– Due to arterial thrombosis after intimal injury
– Risk of delayed rupture or abscess formation
image Active arterial extravasation: High-attenuation focus isodense with aorta, surrounded by lower attenuation clot or hematoma

– May be linear (spurting vessel) or rounded (pseudoaneurysm): Distinction is made using delayed phase images

image Active extravasation (unlike pseudoaneurysm) changes in size and morphology between initial and delayed phases
image Although delayed images are not routinely included in most trauma protocols, addition of delayed images can be helpful if there is site of suspicion noted on initially acquired portal venous phase images

Ultrasonographic Findings

• Subtle laceration may be missed, as ultrasound is insensitive for parenchymal injury

image Lacerations can be hypoechoic or isoechoic to splenic parenchyma and can be very difficult to detect with US
• Free intraperitoneal fluid with low-level echoes representing hemoperitoneum and echogenic perisplenic clot
• Hematoma should be avascular

Angiographic Findings

• Avascular parenchymal laceration with amorphous parenchymal extravasation
• Flattened lateral contour of spleen due to subcapsular hematoma
• Rounded contrast collections (pseudoaneurysms)

Imaging Recommendations

• Best imaging tool

image CECT
• Protocol advice

image Arterial phase images more sensitive for active extravasation or pseudoaneurysm
image Portal venous phase images more sensitive for parenchymal injury (i.e., laceration)
image Delayed images to differentiate active arterial extravasation from pseudoaneurysm

DIFFERENTIAL DIAGNOSIS

Splenic Cleft

• Normal anatomic variant that appears as a thin, fissure-like band of low attenuation
• Most often occurs at upper or lower pole of spleen
• No evidence of adjacent hematoma, free fluid, or stranding

Splenic Abscess

• Rounded, irregular, low-attenuation collection within splenic parenchyma
• Clinical signs of infection: Fever, increased white blood cell count, left pleural effusion
• No history of trauma or hemoperitoneum

Splenic Infarct

• Wedge-shaped area of low attenuation usually located at periphery of spleen
• Associated with splenomegaly, systemic emboli (such as from endocarditis), and multiple other causes
• Typically no surrounding free fluid or hematoma (in the absence of rupture)
• Infarct may evolve into abscess

Splenic Cyst

• Rounded, nonenhancing cystic lesion with definable cyst wall ± peripheral calcification

Lymphoma

• Single or multiple hypodense lesions ± splenomegaly
• Hypoechoic on US with minimal color Doppler flow
• PET positive

Splenic Tumors

• Hemangioma

image Most common benign tumor: 0.3-14% of adults at autopsy
image Delayed retention of contrast on CECT, echogenic on US, and high T2 signal on MR
• Hamartoma

image Rounded, discrete mass in asymptomatic patient
image Often isodense on CECT and hyperintense on T2 MR sequence
• Lymphangioma

image Multifocal or multiseptate cystic mass
image Fibrous bands between dilated lymphatic spaces
image Mural calcifications on NECT
• Littoral cell angioma

image Multiple hypoattenuating masses typically seen in setting of splenomegaly
image Vascular channels lined with endothelial cells with dilated vascular spaces

PATHOLOGY

General Features

• Etiology

image Most commonly due to blunt trauma with blow to left upper quadrant (LUQ)

– Motor vehicle collisions most common cause
image Penetrating trauma to spleen less common
image Rarely iatrogenic trauma to spleen during surgery (particularly colon surgery)
image Increased risk of splenic injury in patients with splenomegaly (from any cause)
• Associated abnormalities

image Injuries to left thorax, tail of pancreas, left liver lobe, &/or mesentery

Staging, Grading, & Classification

• Grading may be misleading: “Minor” injuries may go on to devastating delayed bleed or delayed rupture
• AAST (American Association for Surgery of Trauma) grading system is based on extent of injury at laparotomy and applied to CT findings

image Does not take into account active extravasation and pseudoaneurysm formation
image I: Subcapsular hematoma (< 10% of surface area of spleen) or laceration < 1 cm
image II: Subcapsular hematoma (10-50% of surface area of spleen) or laceration 1-3 cm
image III: Subcapsular hematoma (> 50% of surface area of spleen), parenchymal hematoma > 5 cm or expanding laceration > 3 cm or involving trabecular vessels, ruptured subcapsular or parenchymal hematoma
image IV: Laceration involving segmental or hilar vessels with devascularization/infarct of at least 25% of spleen
image V: Shattered spleen; hilar vascular injury with complete devascularization/infarct of spleen
• Marmery MDCT-based grading system

image I: Subcapsular hematoma (< 1 cm thick), laceration (< 1 cm in depth), or parenchymal hematoma (< 1 cm in diameter)
image II: Subcapsular hematoma (1-3 cm thick), laceration (1-3 cm in depth), or parenchymal hematoma (1-3 cm in diameter)
image III: Subcapsular hematoma (> 3 cm thick), laceration (> 3 cm in depth), or parenchymal hematoma (> 3 cm in diameter); splenic capsular rupture
image IVA: Active extravasation in intraparenchymal or subcapsular hematoma; pseudoaneurysm or arteriovenous fistula; shattered spleen
image IVB: Active intraperitoneal bleeding

Gross Pathologic & Surgical Features

• Varies according to extent of injury

image Laceration, fractures, or subcapsular hematoma

Microscopic Features

• Necrotic injured tissue with surrounding hematoma

CLINICAL ISSUES

Presentation

• Most common signs/symptoms

image Blunt abdominal trauma, LUQ pain, hypotension

– Often associated with left chest pain due to rib fractures, left lower lobe lung consolidation, or left hemothorax
– Injury to other abdominal organs in 36.5%
– 80% with splenic injury have extra-abdominal injuries

Demographics

• Epidemiology

image Most commonly injured solid abdominal organ in blunt trauma
image Most common abdominal organ injury requiring surgery

Natural History & Prognosis

• Prone to develop delayed hemorrhage, but excellent prognosis with early intervention (surgery/embolization)
• Identification of active arterial extravasation or pseudoaneurysm best predictor of need for surgery and failure of nonoperative management

Treatment

• Hemodynamically unstable patients with splenic injury undergo surgery if focused assessment with sonography for trauma (FAST) scan or diagnostic peritoneal lavage (DPL) are positive.

image 29% of all patients and 40% of children may not have hemoperitoneum and DPL/FAST may be falsely negative
• Hemodynamically stable patients with AAST grade I-III splenic injury and without other injuries often conservatively (observation or embolization) managed

image Conservative management in up to 70% of cases
image Avoids risks of surgery and post-splenectomy sepsis
image Active extravasation, pseudoaneurysm, or hemoperitoneum in hemodynamically stable patients managed with embolization
image Embolization generally not utilized for higher grade (> III) injuries and older patients → splenectomy
image Splenectomy in higher grade injuries, hemodynamic instability, or failed conservative management (delayed splenic rupture)
• Nonoperative management generally preferred in pediatric patients

DIAGNOSTIC CHECKLIST

Consider

• Consider congenital splenic cleft (rather than laceration) in absence of perisplenic hematoma or free fluid
• Innocuous splenic injuries may lead to life-threatening delayed hemorrhage, especially with anticoagulation
image
(Left) Axial CECT in a 39-year-old woman who sustained multiple injuries in a motor vehicle accident shows the irregular and linear areas of decreased enhancement image within the spleen.

image
(Right) Axial CECT in the same patient again illustrates the areas of decreased enhancement within the spleen image, as well as a small perisplenic hematoma image in this typical case of splenic laceration.
image
(Left) Axial CECT shows a splenic fracture with active extravasation. Note the fracture of the lower pole image featuring a site of high-attenuation arterial extravasation image.

image
(Right) Axial CECT in the same patient demonstrates a large perisplenic hematoma image and extensive arterial extravasation image.
image
(Left) Axial CECT in a young man injured in a motor vehicle accident shows a splenic parenchymal laceration image with a high density clot image adjacent to the spleen.

image
(Right) Axial CECT in the same patient again illustrates the clot adjacent to the spleen image, as well as lower density and more homogeneous blood elsewhere within the peritoneal cavity image. This is characteristic of the sentinel clot sign. The injury healed without surgical intervention.
image
Axial CECT shows a shattered spleen following blunt trauma. Note the multiple areas of active arterial extravasation within the poorly enhancing spleen image.

image
Axial CECT at a more caudal level in the same patient shows massive arterial extravasation into the peritoneal cavity image. Note the thickened small bowel loops image and flattened inferior vena cava (IVC) indicating hypoperfusion syndrome.
image
Axial CECT shows multiple deep splenic lacerations image following blunt trauma. Note the small amount of perisplenic blood image.
image
Axial CECT in the same patient shows moderate pelvic hemoperitoneum image. Despite hemodynamic stability during the scan, this patient had massive delayed bleeding 24 hours later, requiring urgent surgery.
image
Axial CECT shows a subcapsular hematoma with flattening of the lateral contour of the spleen image.
image
Axial CECT at a more caudal level in the same patient demonstrates active arterial extravasation into the subcapsular hematoma image.
image
Axial CECT showing a splenic fracture with active bleeding. Note the area of high-attenuation arterial extravasation image.
image
Axial CECT of a splenic fracture shows a jet of active hemorrhage image in the left paracolic gutter.
image
Axial CECT of a splenic laceration with active bleeding. Note the low attenuation area of parenchymal laceration image with adjacent active bleeding image.
image
Axial CECT of a splenic fracture with active bleeding. Note the nonenhancing area of splenic fracture image and high-density active bleeding image.

Share this: