SA Medical - General Medicine And Imaging of Disease

An approach to soft tissue masses. Clinical examination and ultrasound review of soft tissue masses may lead to: A specific diagnosis A mass like lesion No sonographic abnormality Specific diagnosis include a foreign body, henia, ganglion cyst, lymph node, Bone and calcifications, epidermal cysts, abscess and hematoma. Mass like lesions may either be superficial and less than 5cm Characteristic of a lipoma ; consider clinical follow up or MRI Not characteristic of a lipoma; consider excision, needle biopsy, or MRI. Mass like lesions may be deep or greater than 5cm in depth.  Please consider an MRI of the extremity in question or a CT of the CHEST and ABDOMEN. In the event of a suspicious  clinical examination, but No sonographic abnormality ; consider MRI or CT. Specific diagnosis  on US:  a foreign body : including wood, glass and metal may be visualised on US. Wood usually has a echogenic focus with abnormal shadowing deep to the foreign body.

Baker cysts are most often found incidentally when the knee is imaged for other reasons. Baker cysts , or  popliteal cysts: Location: They are usually located at or below the joint line; arising in the popliteal fossa  between the medial head of the  gastrocnemius  and the  semimembranosus   tendons that communicates with the  knee joint .  T hey occur as a communication between the posterior joint capsule and the gastrocnemius-semimembranosus bursa,  resulting in fluid being squeezed in one direction . Consistency: fluid-filled distended synovial-lined lesions. They are not a true bursa nor a true cyst.  They are seen between 4-7 years and in adults above 35 years. Differential diagnosis:  DVT:  Symptomatic presentation may be acute when rupture occurs, in which case the chief differential diagnosis is  deep venous thrombosis .  Mass: A chronic/subacute presentation can manifest as a popliteal fossa mass or with pain. Ultrasound:  Normally the first line in

Definition    food group : A  food group  is a collection of  foods  that share similar nutritional properties or biological classifications. Nutrition guides typically divide  foods  into  food groups  and recommend daily servings of each  group  for a healthy diet. 5 different food groups: Dairy is a   source of calcium.      Calcium  occurs mainly in the teeth and bones. Carbohydrates give the body energy Protein  helps to repair muscle and bone. Fats store energy and insulate the body. Needed to absorb fat soluble vitamins.   Vitamins and minerals  boost the immune system. Dietary minerals are derived from the earth's crust.    Inorganic elements that are essential to humans for normal body function. Plants extract the minerals from the soil, and humans consume the plants. Iron is an example of a mineral which is a constituent of  hemoglobin  found in  blood. The five different food groups are: Dairy : the foods in this group are excellent sources of calcium,

Draped aorta sign Draped aorta sign: posterior wall of the aorta either is not identifiable or closely follows vertebral bodies Hyperattenuation crescent sign • Hyperattenuation crescent sign: welldefined peripheral crescent of increased attenuation within the thrombus of a large aneurysm indicates acute or impending rupture loss of “wink” sign Noncompressibility of vein (loss of “wink” sign) DVT popliteal “dog-leg” sign (aCute bend in the lumen of the popliteal artery) • Popliteal aneurysm: Most common peripheral arterial aneurysm. 50% of aneurysms are bilateral, and 80% are associated with aneurysm elsewhere. Commonly due to atherosclerotic disease or trauma. Angiography may show luminal dilatation or mural calcification. 25% of popliteal artery aneurysms may not be associated with visible arterial dilatation by angiography. In these cases, secondary signs such as the “dog-leg sign” (acute bend in lumen o

Adrenal hemorrhage Etiology: Underlying tumor; Coumadin; Trauma; Infection; Hypercoagability states; stress CT findings: high attenuation on NECT; may be unilateral or bilateral; in time may calcify; more common in females (3:1) If bilateral adrenal hemorrhage in trauma consider addison syndrome need hormonal replacement therapy as life treatening (Emergency Radiology 2012; Sacerdote) Variable appearnace of lesion: Round; Blunt abdominal trauma findings: Adrenal hematoma (oval or round); irregular hemorrhage obliterating the gland; uniform adrenal gland swelling with increased attenuation; preiadrenal hemorrhage or stranding; retroperitoneal hemorrhage; adrenal pseudocyst (chronic) (Emergency radiology 2012 To'o) Bright Adrenals in Trauma  Patient is hypotensive; hypovolemic shock syndrome  Hypovolemic shock CT findings Bright Adrenals; Diffuse fluid filled dilated small bowel; hyperenhancement

Biological Effects of radiation: Stocastic (delayed) effects and Non-stocastic (deterministic) effects Stocastic (delayed) effects - cancers in exposed individual: observed 3-20 years after exposure ; - Mutations in offspring of exposed individual - observed in future generations Probability of effect increases with dose, with no dose threshold, but the severity of the effect is not dose related. E.g. radiation induced cancer and genetic effects. Playing the Lottery game, more exposure, more chances of effect. Cancer risk: average risk for radiation induced cancer in general population is 5% per Sievert (Sv); Children are 2-3 times at higher risk then adults (as high as 15% per Sv); for persons aged >50 yars risk is 1/5 to 1/10 of the for younger adults Non-stocastic (deterministic) effects: - direct damage to tissue due to local cell death; - observable within days to weeks Threshold dose; >2 Grey of radiati

Adynamic ileus, Pneumatosis intestinalis,  Gas in portal vein may be seen transiently,  Pneumoperitoneum football sign NeCrotiziNg eNteroColitis (NeC) Radiographic Features (Fig. 11-30) • Small bowel dilatation: adynamic ileus (first finding), unchanging configuration over serial radiographs • Pneumatosis intestinalis, 80% (second most common sign) • Gas in portal vein may be seen transiently (US more sensitive than plain film); this finding does not imply as bad an outcome as it does in adults. • Pneumoperitoneum (20%) indicates bowel perforation: football sign (floating air and ascites give the appearance of a large elliptical lucency in supine position). • Barium is contraindicated; use water-soluble contrast if a bowel obstruction or Hirschsprung disease needs to be ruled out. Bilateral. C sign in subtalar bony coalition. tarsal CoalitioN (Fig. 11-69) Fusion of 2 or more tarsal bones. Union may be

Absent double decidual sign with MSD >10 mm prediCtors of poor outCome in first trimester  Anterior uterine wall displaced away from fetal body normal amniotiC fluid Volume Several methods are used for assessment of fluid; there is no evidence that any method is better than the other: • Subjective assessment (recommended by most sonographers) Anterior uterine wall displaced away from fetal body (good sign) Banana sign (spina bifida) Banana sign (spina bifida), Posterior fossa Cerebellar view • Banana sign (Fig. 10-28): represents the cerebellum wrapped around the posterior brainstem secondary to downward traction of the spinal cord as part of Arnold-Chiari malformation • Most cases of spina bifida are suspected because of head abnormalities (e.g., banana sign). Double decidual sac sign Pregnancy? • Visualize gestational sac • Double decidual sac sign Double Decidual

Cystic duct sign • Morphine is often given before 4 hours to make the diagnosis of acute cholecystitis. Dose is 0.04 mg/kg given slowly. Causes spasm of sphincter of Oddi Can convert true-positive result in case of cystic duct sign to false-negative result DIFFUSE PERIOSTEAL UPTAKE (TRAMTRACK SIGN) Criteria: bilateral, diffuse periosteal uptake • Hypertrophic osteoarthropathy (lower extremity > upper extremity) • Child abuse • Thyroid acropachy dilated cavity on initial but not delayed images Heart size and wall thickness • Subjective assessment • Transient cavitary dilatation (dilated cavity on initial but not delayed images) is a sign of LV dysfunction. Hot nose sign Imaging Findings • No flow Absent ICA Absent sinuses • Absent cerebral uptake of HMPAO • Slight perfusion of scalp veins may be present. • Hot nose sign: increased intracranial pressure

atherosCLerotiC disease Slim sign: collapse of ICA above stenosis atherosCLerotiC disease atherosCLerotiC disease Color Doppler flow imaging of carotid arteries • High-grade stenosis with minimal flow (string sign in angiography) is detected more reliably than with conventional Doppler US. CT • To determine complete occlusion versus a string sign (near but not complete occlusion), delayed images must be obtained immediately after the initial contrast images. Bifid post-CS sign (85%) Bifid post-CS sign (85%) cap sign • T2W: hyperintense. 20%-33% of ependymomas demonstrate the “cap sign,” a rim of extreme hypointensity (hemosiderin) seen at the poles of the tumor on T2W images. Most cases (60%) also show evidence of cord edema around the masses. Classification of Plain Radiographic Abnormalities of the Infant Skull Variations in skull density Decreased density: generalized or local