Short Notes Flashcards
Types of UB injruy
Intraperitoneal bladder rupture (dome of the bladder)
Extraperitoneal bladder rupture (base of the bladder)
Imaging findings suggestive of ovarian simple cyst
Anechoic
Posterior acoustic enhancement
Thin invisible wall
No increased vascular flow on doppler
Surrounded by normal ovarian tissue
Mri: homogeneous, T1: low signal intensity (dark). T2: very high signal intensity (bright)
Post contrast : thin and featureless wall enhancement
Imaging findings suggestive of ovarian dermoid cyst
Hyperechoic mass
Distal acoustic shadowing with/without hyperechoic lines
Non dependent fliud level
Mri: T1: fat is T1 hyperintense, Fat suppression: loss of T1 signal. T2: hyperintense
Imaging findings suggestive of hemorrhagic cyst:
NB: hx of sudden onset of pelvic pain
US: thin walled complex cyst, often with fine septations appears as a reticular pattern “lacy”.
Multiple low level thin internal echoes, may show fluid-fluid level or clot retraction
Wall may be focally or diffusely thickened.
No blood flow within the cyst or the septations, may be seen peripherally
MRI: T1: iso to hyperintense T2: hyperintense
Characteristics of malignant nodule
Margin: irregular or spiculated margins
Diffuse and amorphous or punctate Calcification
Growth rate: doubling time is usually between 30 and 400 days
Contrast enhancement of >20 HU
Increased FDG uptake on PET
Causes of pulmonary embolism
DVT
C/S
Fracture of long bone
Difference between cystadenoma and cystadenocarcinoma
Cystadenoma:
Thin wall, single large cystic cavity, thin few spetations
cystadenocarcinoma:
Thick wall, solid nodule, thick&many septations, ++vascularity, ascitis, lymphadenopathy, liver metastasis, and pleural effusion.
Radiological signs of dermoid cyst:
By USS: complex partially cystic mass with high echogenic contents like fat, or teeth and bone, with posterior shadowing.
May show echogenic lines and dots (hair).
The fat is floating in the top of the lesion, forming fat fluid level
Little or no internal flow
+
Dot and dash or salt and papper
Tip of iceberg
Rokitansky nodule inside it
Fat
Tooth
Sac of marbles
BIRADS
BIRADS 0: incomplete assessment
BIRADS 1: negative
BIRADS 2: benign
BIRADS 3: Probably benign
BIRADS 4: probably malignant
BIRADS 5: malignant
BIRADS 6: biopsy proven malignancy
Difference between EDH and SDH
About EDH:
need sudden strong trauma, so it is associated with a skull fracture
Lens shaped hge
Always acute: hyperdense
Always unilateral (coup)
Cannot cross suture
Can cross falx cerebri
Common in young
Due to rupture of middle meningeal vessels (A>V)
Difference between EDH and SDH
About SDH:
Need repeated minor trauma( no skull fracture)
Crescent shaped hge
May be acute, subacute, or chronic
May be unilateral(coup) or bilateral( coup&countercoup)
Can cross sutures
Cannot cross falx cerebri
Common in old age due to brain atrophy(no support to veins)
Due to rupture of cortical bridge veins
Complicated Meningitis
Sub or epidural empyema
Ventriclitis
Brain infarction
Secondary hydrocephalus
DDs od ring enhanced lesion
Cerebral abscess
Neurocysticercosis
Metastasis
Glioblastoma
Causes of intraventricular hemorrhage (primary)
Anticoagulation
HTN
Aneurysm
Substance abuse
Trauma (less likely)
NB: Often will need an external ventricular drain
Acute vs chronic stroke
Pathology:
Acute: cytotoxic edema
Chronic: encephalomalacia: wallerian degeneration
density: both hypoattenuated
Acute: more dense than CSF
Chronic: CSF density
Mass effect:
Acute: positive (volume gain) sulci and gyri effacement and midline shift or herniation
Chronic: negative (volume loss) widened sulci, ex vacuo dilatation of ipsilateral ventricle
Mention three radiological modalities used in the dx of Pulmonary embolism
Chest X-ray (initial investigation, non specific)
CT Pul. Angiography (CTPA).
Ventilation/perfusiom lung scan
Pumonary angiography (gold standard)
Principles of radiation protection
Distance
Time
Shielding
Contraindications of MRI
- pacemaker or defibrillator
- Bullets or gunshot pellets
- Cerebral aneurysm clips
- Cochlear implant
Uses of Barium with names:
Oral route:
Barium swallow for esophagus
Barium meal for stomach
Barium follow through for small bowel
Retrograde rectum route
Barium enema for colon
Definition of stroke
Sudden, focal neurological deterioration due to a disturbance in the blood supply to the brain
Goals of imaging in acute stroke
Rule in or out other disease process.
Define location, extent, and age of infarction
Do so as rapid as possible
Imaging modalities for acute stroke
CT
MRI
DWI MRI
PWI MRI
DSA
Doppler carotid
Early signs of ischemic infarction
Dense artery sign
Effacement of sulci
Poor differentiation of gray-white matter
MRI T1appearance of blood according to the age of storke:
Hyperactute: isointense
Acute: isointense
Early subacute: bright
Late subacute: bright
Chronic: dark
MRI T2 appearance of blood according to the age of storke:
Hyperactute: bright
Acute: dark
Early subacute: dark
Late subacute: bright
Chronic: dark
Advantages of conventional radiography
Cheap
Fast
Low radiation
Protable machines
Still the most widely obtained imaging studies
Disadvantages of conventional radiography
Limited range of densities
Ionizing radiation
Advantages of Fluoroscopy
Widely available
Inexpensive
Functional and anatomical imaging
No sedation required
Disadvantages of Fluoroscopy
Requires: ingestion or injection of contrast medium (patient cooperation) and risks for allergy and renal insufficiency
Radiological hazard:
Time consuming
It is time-consuming because we are following contrast agents inside organs
X-ray uses medical field
Plain X-rays are mostly used to detect pathology in the skeletal system.
Sometimes used for soft tissue:
-Chest X-ray to identify lung disease like pneumonia or lung cancer
-abdominal X-ray to detect intestinal obstruction?, free air or free fluid.
Disadvantages of CT
Expensive
Need large space
Ionizing radiation
Usually requires IV contrast
Can’t detect intra articular abnormalities
Dense bone (petrous ridge for example) and metal cause severe artifact.
Major benefite of CT scanning over conventional radiography
Ability to expand the gray scale
Multislices CT scanner permits very fast imaging
New applications: virtual colonoscopy and vitrual bronchoscopy, cardiac ca scoring, CT coronary angiography
Advantages of US
Doppler for flow
No radiation l
Can be portable
Relatively inexpensive
Disadvantages of US
Highly dependent on patients body size and US operator
Air or bowel gas prevents visualization of structures
Common calcified structures in CNS
Pineal gland
Basal ganglia
Choroidal plexus
Signs of pulmonary embolism
Localized area of consolidation
Localized area of collapse
Pleural effusion
Advantages of MRI
non Ionizing radiation
Produce much higher contrast bt different types of soft tissues than even CT
MRI is widely used in neurologic imaging (sensitive in soft tissue imaging)
Disadvantages of MRI
Expensive
Not widely available
Uncooperative patients need sedation or aensthesia
Modern implants may cause black artifact
Radiological findings of pulmonary edema
Bilateral opacifications (Bat wings signs)
Bilateral consolidation
kerley B line
++cardiac thoracic ratio
CXR trauma findings
Hemothorax
Pneumothorax
Ribs fractures (Flail chest)
Pulmonary contusions
Subcutaneous emphysema
Mediastinal widening (possibe aortic injury)
Contraindications of IVU
Renal insufficiency
Multiple consecutive contrast study
H/O allergy
Cardiac disease
Patients who are on stop the drug 48hr before contrast injection
IVU good for
Show the renal function
UT obstruction
Renal and bladder mass
Congenital anomalies
Localization of ectopic kidney
The cause of UT obstruction :
In men: BPH or prostatic cancer
In women: gynecological cancers and pregnancy
In young adults: calculi is most common
In children: reflux and ureteropelvic junction obstruction
Types of nephrocalcinosis
Medullary nephrocalcinosis (95%)
Cortical nephrocalcinosis (5%)
Pratial, combined
Radiographic features of Chronic pyelonephritis
Renal scarring
Renal atrophy
Renal cortical thinning
Compensatory hypertrophy of residual normal tissues
Calyceal Clubbing
Thickening and dilatation of the calyceal system
Overall renal asymmetry
Conditions associated with autosomal dominant polycystic kidney disease
Cerebral berry aneurysms
HTN
Colonic diverticulosis
Bicuspid aortic valve
Mitral valve prolapse
Aortic dissection
Causes of bladder Calcification
Stone
Calcification in the wall is rare (due to schistosomiasis or bladder tumor)
Two type of neurogenic bladder
Large atonic
Hypertrophic type
Causes of bladder outlet obstruction :
3 bladdr
3 prostate
2 urethra
Bladder tumor
Bladder neck stenosis
Neurogenic Bladder
BPH
Prostatic cancer
Prostatitis
Urethral stone
Urethral strictures
Normal indentations of the esophagus
Aortic arch (22.5 cm)
Left bronchus (27.5 cm)
Enlarged left atrium
Signs of peptic stricture
Short
Smooth outline
Tapering ends
Ulcer may be seen close to stricture
Cuases of esophageal stricture
Peptic (GERD)
Carcinoma
Achalasia
Corrosive
Surgery
Modalities and radiological signs of congenital hypertrophic pyloric stenosis
X-ray: single bubble sign
Barium meal: string sign, Shoulder sign, mucosal nipple sign, mushroom sign, 🤷♂️also umbrella sign, tram track sign
USS (best): cervix sign, antral nipple sign, target sign
US measurement in congenital hypertrophic pyloric stenosis
Pyloric muslce wall thickness >3mm
Pyloric transverse diameter >14mm with closed Pyloric channel
Elongated pyloric canal >17 mm in length
Exaggerated peristaltic waves
Examples of extramural lesions compressing the esophagus
Carcinoma of the bronchus
Enlarged mediastinal lymph node
Aneurysm of aorta
Features suggesting malignant gastric ulcer
Doesn’t protrude beyond the gastric contour (endoluminal)
Irregular and shallow ulcer crater
Nodular and angular ulcer mound
Nodular gastric folds
Carman meniscus sign
More often along the greater curvature
Features suggesting benign gastric ulcer
Site: along lesser curvature in gastirc body and antrum
Outpouching of ulcer crater beyond the gastric contour
Smooth rounded and deep ulcer crater
Smooth ulcer mound
Smooth gastric folds
Hampton’s line
