SA Medical - General Medicine And Imaging of Disease

Blood–brain barrier damage A pathological increase of permeability of the blood–brain barrier occurs in several conditions, e.g. many cerebral and meningeal tumours, cerebral infarcts and in some infections. This is the basis of the very useful diagnostic sign of tumour staining, which is particularly well seen on CT, even after IV injection of contrast medium.

multiplicity is not a sign of a benign condition US guidelines for thyroid nodules: • 80% of nodular disease is due to hyperplasia (pathologically they are referred to as hyperplastic, adenomatous, or colloid nodules). • Malignant and benign nodules present simultaneously in 10%-20% of cases; thus multiplicity is not a sign of a benign condition. • Nodules with large cystic components are usually benign; however, 20% of papillary cancers are cystic. • Comet-tail artifacts are seen in colloid cysts.

Beak sign on IVP • “Beak sign” can be seen with large cysts seen on IVP Bergman's coiled catheter sign Bergman's coiled catheter sign: on retrograde pyelogram the catheter is typically coiled in dilated portion of ureter just distal to the lesion. Doughnut sign on IVP or angiography Lobar dysmorphism: doughnut sign on IVP or angiography Goblet sign Goblet sign: retrograde pyelogram demonstrates dilated ureteral segment distal to obstruction with filling defect and meniscus Ureteral tumors Pseudokidney sign (US) Elliptical structure in pelvis or abdomen with an echogenic center (blood, prominent mucosa, infiltrated bowel wall) resembling the US appearance of a kidney. • Inflammatory bowel disease Crohn disease Infectious colitis • Tumor • Intussusception • Always exclude pelvic kidney Ring sign Sequestered, sloughed papillae cause filling d

Accordion sign • Contrast between thickened folds (accordion sign) Pseudomembranous colitis (PMC) Bull's eye pattern (hypoechoic halo around lesion) LIVER US FOR METASTASIS Echogenic metastases • GI malignancy • HCC • Vascular metastases Hypoechoic metastases • Most metastases are hypovascular. • Lymphoma • Bull's eye pattern (hypoechoic halo around lesion) Nonspecific sign but frequently seen in bronchogenic carcinoma Hypoechoic rim represents compressed liver tissue and tumor fibrosis. Calcified metastases: hyperechoic with distal shadowing • All mucinous metastases: colon > thyroid, ovary, kidney, stomach Cystic metastases: necrotic leiomyosarcoma; mucinous metastases Carman's (meniscus) sign* *Results from the fluoroscopically induced apposition of rolled halves of the tumor margin forming the periphery of the ulcerated carcinoma; meniscus refers to menisco

Atoll sign  Atoll sign (ring-shaped opacity) COP - Cryptogenic organizing pneumonia (COP) Bilateral Pulmonary Hypoplasia  Pulmonary hypoplasia in the neonate can be unilateral or bilateral. Bilateral pulmonary hypoplasia is most often the result of compression of the lungs during fetal development. Congenital bone dysplasias and syndromes associated with hort ribs and a small thoracic cage (asphyxiating thoracic dystrophy, thanatophoric dwarfism, Ellis-van Creveld syndrome) compress the lungs and cause hypoplastic lungs. The degree of hypoplasia is often severe and leads to the demise of these infants. Chromosomal abnormalities such as the trisomies are associated with hypoplastic lungs, and in some infants, hypoplasia is “primary” and unexplained.  Black pleura sign Pulmonary alveolar microlithiasis - Sandlike microcalcifications of lung (black pleura sign) Cheerio sign Bronchioloalveolar carcinoma

Calcification of coronary arteries  Calcification of coronary arteries are the most reliable plain film sign of CAD (90% specificity in symptomatic patients), but calcified coronary arteries are not necessarily stenotic. Figure-3 sign Pseudocoarctation Gated CT Chest Retrospective or prospective ECG gated minimize motion artifact from the beating heart; Use of gating enables coronary artery and aortic valve evaluation Indication: anterior chest pain and suspicion of ascending aortic disection requires gating; Coronary artery evaluation - coronary artery disease Functional Valve Imaging requires retrospective cardiac gating Retrospective imaging - functional evaluation prospective ECG gated - limited by CT scan type; lower dose of radiation; LV aneurysm LV aneurysm is the second most reliable plain film sign of CAD. It develops in 20% MI. Normal Aortic Valve 64-detectot c

Circumscribed masses with well-defined borders  Circumscribed masses with well-defined borders (>75% circumference): uncommon sign of malignancy; only 2% of solitary masses with smooth margins are malignant. Inverted teardrop • Inverted teardrop: nonspecific sign seen with extensive gel bleed or focal intracapsular rupture; occurs when silicone enters radial fold and then leaks between internal and external capsules linguini sign by MRI • Flaps (“linguini sign” by MRI) may represent intracapsular rupture. Skin thickening (>3 mm)  Skin thickening (>3 mm) may be a sign of malignancy or benign conditions. Types: Focal: local tumor Diffuse: sign of edema; may be due to inflammatory cancer Spiculated tumor margin • Spiculated: a spiculated tumor margin is the only specific sign of malignancy; however, not all spiculated masses are cancers. Spiculated masses are the e

Splenic size is variable depending on age, nutrition, and patient size; normal 12x4x7 cm; splenic volume Apxtransversexsuperior-inferior /2; normal <150g br=""> Acessory spleens are common; failure of fusion, usually <3cm accessory="" br="" don="" enhances="" for="" like="" mistake="" nodes="" round="" spleen="" spleens="" t=""> Lobulations are common; clefts cause lobulations, dont mistake clefts for lacerations or infarcts 10 HU less then liver Variable enhancements due to the variable circulatory routes through the spleen; white pulp (lyphatic follicles and RE cells); Redpulp (interspersed vascular lakes) Patterns of enhancement: serpentine, cord like enhancement most common - more pronounced with fast injection rates; exagerated in certain patients - decreased cardiac output or heart failure, splenic v

Supraglottic area is the area between epiglottis and true vocal cords (a) Congenital: Aryepiglottic fold cyst (b) Inflammatory: Acute bacterial epiglottitis, angioneurotic edema (c) Neoplastic: Retention cyst, cystic hygroma, neurofibroma (d) Traumatic: Foreign body, hematoma, radiation, caustic ingestion (e) Idiopathic: Laryngomalacia

A. BILE DUCTS 1. Biliary colic/bile duct obstruction 2. Acute cholecystitis/cholangitis B. LIVER 1. Acute hepatitis: alcoholic, viral, drug-related, toxic 2. Hepatic abscess 3. Hepatic tumor: metastases, hepatocellular carcinoma, hemangioma, focal nodular hyperplasia, hepatic adenoma 4. Hemorrhagic cyst 5. Hepatic congestion: acute hepatic congestion, Budd-Chiari syndrome 6. Perihepatitis from gonococcal/chlamydial infection (Fitz-Hugh-Curtis syndrome) C. PANCREAS 1. Acute pancreatitis D. INTESTINES 1. Acute appendicitis 2. Peripyloric ulcer 3. Small bowel obstruction 4. Irritable bowel 5. Colitis/ileitis 6. Intestinal tumor E. LUNG 1. Pneumonia 2. Pulmonary infarction F. KIDNEY 1. Acute pyelonephritis 2. Ureteral calculus 3. Renal/perirenal abscess 4. Renal infarction 5. Renal tumor G. OTHERS 1. Costochondritis 2. Herpes zoster