Cystic Diseases Flashcards
What is a cyst?
A walled-off collection of fluid.
What is the main difference between true and acquired cysts?
True cysts have an epithelial wall and acquired cysts do not.
When are true cysts formed?
Congenital
- Hereditary
- Developmental
How are acquired cysts formed? (4)
- Post traumatic (even just aging)
- Infectious process
- Parasitic
- Inflammatory (abscesses)
What features indicate that a cyst is “true”? (2)
- Multiple cysts in one organ
2. Multiple organs with cysts
What features indicate that a cyst is “acquired”?
History/signs/symptoms that indicate trauma, pain, infection or inflammatory processes.
What are the 4 sonographic criteria for a simple cyst?
- Anechoic
- Strong back wall
- Posterior acoustic enhancement
- Oval or round (refractive edge shadow)
What are the sonographic features of a complex cysts? (4)
- Internal echoes
- Septations
- Calcifications
- Thick wall or mural nodularity
What do internal echoes in a cyst indicate?
Hemorrhage or infection
What do septations in a cyst indicate? (4)
Malignancy, hemorrhage, infection or adjacent cysts
What do calcifications in a cyst indicate? (3)
Malignancy, Inflammatory reactions or milk of calcium
What do thick walls or mural nodularity in a cyst indicate?
Malignancy or benign thickening
What increases the occurrence of cysts (especially in the liver and kidneys)?
Age
What can multiple cysts indicate?
A genetic abnormality
What do the effects of cysts depend on?
The number, size and location
What are the possible effects of cysts?
- Asymptomatic
- Pain
- Pressure
- Increased lab values
- Jaundice
- Fever
What lab values would be increased by cysts?
Increased WBC’s (if the cyst is infected).
What lab values may be decreased in the presence of large liver cysts?
Decreased LFT’s
What type of cysts are found in the cortex of the kidneys?
Renal Cortical Cysts
Are Simple Renal Cortical Cysts concerning?
No, they may increase with age but they are typically benign and asymptomatic so they do not require follow-up.
Look at images of simple Renal Cortical Cysts in slides.
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What defines septations as irregular?
Greater than 1 mm in thickness or solid elements.
Does a complex cyst with septations require further imaging?
Yes, if the septations are irregular then the lesion must be presumed malignant until proven otherwise.
Look at the images of the complex Renal Cortical Cysts in the slides.
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What are the two types of polycystic kidney disease?
- Autosomal dominant
2. Autosomal recessive
What is ADPKD?
Autosomal Dominant Polycystic Kidney Disease
What is the most common hereditary renal disorder?
ADPKD
When does ADPKD usually manifest?
The 4th decade
What are the anomalies associated with ADPKD?
- Cerebral berry aneurysms
2. Liver, pancreas, splenic cysts
How often do patients with ADPKD develop renal failure?
50%
What are the signs/symptoms of ADPKD?
- Palpable mass
- Pain
- Hematuria
- Hypertension
- UTI’s
What is the sonographic appearance of ADPKD?
Renal enlargement and multiple cortical and medullary cysts bilaterally.
What lab tests would be affected by ADPKD?
Creatinine and BUN LFT
With respect to the kidneys, how does ADPKD differ from a cortical cyst?
There are multiple cysts seen in both the medulla and cortex.
What is ARPKD?
Autosomal Recessive Polycystic Kidney Disease
What do the different types of ARPKD depend on?
Age
What are the 4 types of ARPKD??
- Perinatal
- Neonatal
- Infantile
- Juvenile
What type of PKD is more serious?
Autosomal Recessive
What abnormalities are more prominent in younger children with ARPKD?
Renal abnormalities
What abnormalities are more prominent in older children with ARPKD?
Liver abnormalities (portal hypertension).
What disease is associated with all types of ARPKD?
Congenital Hepatic Fibrosis
What is the sonographic appearance of ARPKD?
- Massively enlarged echogenic kidneys
- Loss of cortex/medulla differentiation
- Macroscopic cysts (occasionally)
Look at the images of ADPKD and ARPKD in the slides.
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What is the origin of parapelvic cysts?
Believed to be lymphatic
Where are parapelvic cysts located?
In the renal sinus
What are the symptoms of parapelvic cysts?
Asymptomatic
What is the sonographic appearance of parapelvic cysts?
Well defined cysts in the sinus that do not connect with the collecting system.
What is used to differentiate between multiple parapelvic cysts and hydronephrosis?
Intravenous Pyelogram (X-ray) or contrast CT
What kidney condition is due to dilated collecting tubules?
Medullary Sponge Kidneys
What does ectatic mean?
Dilated or distended
What is the etiology of medullary sponge kidneys and when does it manifest?
Unknown etiology, manifests in the 3rd and 4th decade.
How often is medullary sponge kidney found in patients with renal stones?
12%
What is the sonographic appearance of medullary sponge kidneys?
Bilaterally echogenic pyramids that may have calcifications localized to the medullary pyramids.
Look at the images of medullary sponge kidneys.
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What is Medullary Cystic Disease?
It is a genetic disease that is the result of progressive renal tubular atrophy.
What forms does Medullary Cystic Disease have?
Recessive and Dominant
What is the sonographic appearance of Medullary Cystic Disease?
Small, echogenic kidneys with cysts at the pyramids measuring 0.1 - 1.0 cm.
What is MCDK?
Multicystic Dysplastic Kidney
What is Multicystic Dysplastic Kidney?
It is a non-hereditary, developmental condition due to an obstruction of a ureter in utero.
Who is most effected by Multicystic Dysplastic Kidney?
Both males and females, (left and right kidneys) are equally effected.
What happens if Multicystic Dysplastic Kidney is bilateral?
The fetus is incompatible with life and will not survive.
What is the sonographic appearance of Multicystic Dysplastic Kidney? (3)
- Small, malformed kidney unilaterally
- Multiple non-communicating cysts
- Absence of normal renal architecture
What is another name for Primary Congenital Cysts?
Epidermoid cysts of the spleen
What are primary congenital Cysts?
Rare, asymptomatic cyst of the spleen that is completely filled with echogenic internal echoes
What is a Choledochal Cyst?
A fusiform dilation of the extra hepatic bile duct (CBD) caused by an anomalous insertion of the CBD into the pancreatic duct.
Who does Choledochal cysts primarily effect?
Women in the east asian populaton.
What do Choledochal cysts have an association with?
Cholangiocarcinoma
What is the sonographic appearance of Choledochal cysts?
A cystic structure that may contain sludge, stones or a solid neoplasm in the area of the CBD.
What can be difficult to identify when a choledochal cyst is large?
The connection to the bile duct.
What is the most common type of choledochal cyst?
Type one (fusiform dilation of the extrahepatic duct)
What is Caroli’s Disease?
A rare congenital disease that causes dilation of the intrahepatic biliary tree
What does Caroli’s Disease result in? (4)
- Stasis
- Stones
- Cholangitis
- Sepsis
What is the sonographic appearance of Caroli’s Disease?
- Saccular or fusiform dilation of the intrahepatic ducts
- Often diffuse, may be focal
- Dilated ducts may contain stones and sludge
What is the difference between saccular and fusiform?
Saccular is a bulge (dilation) on one side of the vessel and fusiform is a dilation all around.
What other diseases is Caroli’s associated with?
- Autosomal Polycystic Disease
2. Medullary Sponge Kidneys
What is Cystic Fibrosis?
A genetic condition involving exocrine dysfunction.
What is the sonographic appearance of Cystic Fibrosis?
- Increased echogenicity of the pancreas
- Atrophy of the pancreas
- Small cysts (1-3mm) on the pancreas uncommonly seen on US
What are Peritoneal Inclusion Cysts?
Ovarian fluid trapped by adhesions (scars) that encase the ovary.
How do peritoneal inclusion cysts appear?
Simple to complex
What conditions can cause the adhesions of peritoneal inclusion cysts? (5)
- Surgery
- Trauma
- PID
- IBD
- Endometriosis
What are Mesenteric Cysts?
Rare cysts that vary in appearance and size that originate from the lymphatic system or mesothelial lining.
What are GI duplication cysts?
Well defined, double walled cysts that are filled with anechoic fluid.
What are the layers of the GI Duplication cysts?
Inner layer = mucosal layer
Outer layer = Muscular layer
What are Degenerative Prostatic Cysts?
Cysts located in the transitional zone of the prostate
What is the most common type of prostate cyst?
Degenerative Prostate Cyst
Refer to page 369/370 for Degenerative Prostatic Cyst
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What are Congenital Prostatic Cysts?
Mostly asymptomatic cysts around the prostate that are associated with infertility and hematospermia.
What are the types of Congenital Prostatic Cysts? (4)
- Utricle Cyst
- Mullerian Duct Cysts
- Ejaculatory Duct Cysts
- Seminal Vesicle Cysts
What Congenital Prostatic Cyst is associated with unilateral renal agenesis?
Utricle cyst
What Congenital Prostatic Cyst is midline and teardrop shaped?
Utricle Cyst
What Congenital Prostatic Cyst is teardrop shaped with a thick wall?
Mullerian Duct Cysts
Do Mullerian Duct Cysts contain spermatozoa?
No
What shape are ejaculatory duct cysts?
Fusiform
What do ejaculatory duct cysts contain?
Spermatozoa
What type of Congenital Prostatic Cyst is associated with infertility?
Ejaculatory Duct Cyst
What are Seminal Vesicle Cysts associated with?
Ipsilateral renal agenesis
What is the treatment for cysts?
- Cyst aspiration
- Alcohol ablation
- Surgical removal
- Organ transplant
What other methods are used in correlation with Ultrasound to diagnose cysts?
- Lab tests (Elevated WBC’s and LFTS)
- Aspiration/biopsy
- CT/X-ray
What are the layers of the bowel wall and their echogenicities?
- Lumen = hyper
- Mucosal = hypo
- Submucosal = hyper
- Muscularis = hypo
- Serosal = hyper
M’s are hypo (5 layers)
