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1
Q

Xray attenuating order of structures

A

Air < fat < water < bone < metal

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2
Q

Pulse vs continues fluoroscopy with regards to time/ radiation exposure

A

Both time and radiation exposure reduced in pulsed fluoroscopy

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3
Q

The effect of higher U/S frequencies on resolution and attenuation

A

Both increase

Better resolution, but deeper structures more difficult to visualize

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4
Q

Duplex vs colur doppler

A

Duplex:
Gray-scale
Utilizes the doppler effect to visualize the velocity of blood flow past the transducer

Color doppler: assigns a color based on direction.
Red: toward, blue: away

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5
Q

U/S attenuation order of structures

A

Bone (bright) > gray matter > white matter > CSF > air (dark)

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6
Q

Use of different MRI techniques

A

Diffusion-weighted:
Neuroimaging
Detection of acute ischemic stroke

T1:
Anatomic scan

T2:
Pathologic scan

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7
Q

How to reduce risk of contrast mediated nephropathy (GFR<60)

A

NS 1 ml/kg/h since 12 h before to 12 h after contrast administration

If same-day procedure:
0.9% NS or NaHCO3, 3 ml/kg/hr, 1-3 hr pre-procedure and 6 hr post-contrast administration

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8
Q

Contraindications to IV iodine contrast

A 
Multiple myeloma
Adverse reaction previously
DM
Dehydration
Renal failure
Severe heart failure
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9
Q

Contraindication to contrast mediated MRI

A

Adverse reaction

ESRD

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10
Q

U/S with microbubble contrast enhancement contraindication

A

Rt to Lt cardiac shunt

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11
Q

Barium contrast contraindications

A

Toxic megacolon

Acute colitis

Suspected perforation

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12
Q

PA vs lateral CXR in picking up pleural effusion

A

Lateral more sensitive

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13
Q

Xray view for lung apices

A

Lordotic view

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14
Q

Ribs on Xray

A

Inspiration:
6th anterior
10th posterior

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15
Q

Cardiomegaly on CXR

A

Cardiothoracic ratio > 0.5

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16
Q

Spine sign on CXR

A

On lateral film, Vertebral bodies should appear progressively Radiolucent as one moves down that thoracic vertebral column. If they appeared more radio-opaque, it is an indication of Pathology. for example consolidation in overlying left lower lobe

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17
Q

Using silhouette sign, what is the location of pathology if SVC/Rt superior mediastinum interface lost?

A

RUL

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18
Q

Using silhouette sign, what is the location of pathology if Rt heard border interface lost?

A

RML

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19
Q

Using silhouette sign, what is the location of pathology if Rt hemidiaphragm interface lost?

A

RLL

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20
Q

Using silhouette sign, what is the location of pathology if aortic knob/Lt superior mediastinum interface lost?

A

LUL

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21
Q

Using silhouette sign, what is the location of pathology if left heart border interface lost?

A

Lingula

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22
Q

Using silhouette sign, what is the location of pathology if left hemidiaphragm interface lost?

A

LLL

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23
Q

Indications of HRCT

A

Hemoptysis

Diffuse lung disease

Pulmonary fibrosis

Normal CXR but abn PFT

Solitary pulmonary nodule

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24
Q

Low dose CT

A

1/5th radiation

Screening

F/U of infections, lung transplant, metastases

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25
CTA indications
PE Aortic aneurysm Aortic dissection
26
Persisting athelectasia in the absence of a known etiology
CT thorax
27
Linear interstitial patterns
Kerley A: Long thin lines in upper lobes Kerley B: Short horizontal lines extending from lateral lung margine Kerley C: Diffuse linear pattern throughout lung
28
DDx of linear interstitial patterns
Pulmonary edema Lymphangitic carcinomatosis Atypical interstitial pneumonias
29
Nodular pattern of interstitial lung disease
1-5 mm, well-defined, evenly distributed throughout lung
30
DDx of nodular interstitial pattern
Malignancy Pneumoconiosis Granulomatous disease: sarcoidosis, miliary TB
31
Reticular (honeycomb) interstitial lung pattern
Parenchyma replaced by thin-walled cysts. Suggests extensive destruction of pumonary tissue anf fibrosis
32
DDx of reticular interstitial pattern
IPF Asbestosis Collagen vascular disease Complication: pneumothorax
33
Drugs causing ILD
``` Cephalo Notrofurantoin NSAIDs Phenytoin Carbamazepine Fluoxetine Amiodarone Chemo : MTX Heroin Cocaine Methadone ```
34
Mx of ILD
HRCT | Bx
35
Infections presenting as pulmonary nodule
Histoplasmosis Coccidioidomycosis Tuberculosis
36
Mx of lung nodule
If high probability of malignancy: Invasive testing If low probability: Repeat CXR/CT in 1-3 mo, then q 6 mo for 2 yr
37
Upper ILDs
``` Farmer’s lung Ankylosing spondylitis Sarcoidosis Silicosis TB Eosinophilic granuloma NF ```
38
Lower ILDs
``` BOOP Asbestosis Drugs Rheumatological disease Aspiration Scleroderma Idiopathic pulmonary fibrosis ```
39
Margin of benign vs malignant pulmonary nodule
M: ill-defined/spiculated B: well-defined
40
Contour of benign vs malignant pulmonary nodule
M: lobulated B: smooth
41
Calcification of benign vs malignant pulmonary nodule
M: eccentric or stipled B: diffuse, central, popcorn, concentric
42
Doubling time of benign vs malignant pulmonary nodule
M: 20-460 d B: <20 d, > 460 d
43
Size of benign vs malignant pulmonary nodule
M: > 3cm B <3 cm
44
Cavitation in benign vs malignant pulmonary nodule
M: yes, esp with wall thickness > 1.5 cm, eccentric cavity and shaggy internal margins B: no
45
Satellite lesion in benign vs malignant pulmonary nodule
M: no B: yes
46
Other features in favor of malignant nodule
``` Colapse LAP Pleural eff Lytic bone lesions Smoking Hx ```
47
Patterns of interstitial fluid accumulation in pulmonary edema
Loss of definition of pulmonary vasculature Peribronchial cuffing Kerley B lines Reticulonodular pattern Thickening of interlobar fissures
48
Vascular changes on CXR in pulmonary edema
Vascular redistribution Vascular enlargement Cephalization Pleural effusion Cardiomegaly
49
Bat wing or butterfly pattern is the result of
Alveolar fluid collection
50
Emboli can be seen in up to which order of arterial branching in PE?
4th
51
CTA and V/Q scan in PE
V/Q scan is not a diagnostic study CTA: definitive
52
The CXR view with most sensitivity for pleural effusion detection
Lateral decubitus: 25 ml
53
Pleural effusion volumes needed to be detected on CXR
Lateral decubitus: 25 cc Upright lateral: 50cc PA: 200 cc
54
A horizontal fluid level is seen in:
Only hydropneumothorax
55
Standard of care for detection of pleural effusion in acute situations
Point of care U/S
56
Indication to perform thoracentesis
Fluid level > 1 cm on lateral decubitus
57
CXR view woth better visualization of pneumothorax
Expiratory Lateral decubitus
58
How to detect pneumothorax on supine film
Deep costophrenic sulcus sign Double diaphragm sign Hyperlucent hemithorax Sharpening of adjacent mediastinal structures Mediastinal shift if tension pneumothorax
59
Most common finding in CXR of asbestos
Benign pleural plaques (may calcify)
60
CXR of asbestos
Pleural plaques Diffuse pleural fibrosis Effusion Malignant mesothelioma
61
DDx of anterior mediastinum
Thyroid Thymus Teratoma Terrible lymphoma
62
DDx of middle mediastinum lesions
``` Esophageal lesions LAP hiatus hernia Bronchogenic cyst Metastatic disease ```
63
Posterior mediastinum lesions
Neurogenic tumors (NF, schwanoma) MM Pheo Neurenteric cyst Thoracic duct cyst Lateral meningocele Bochdalek hernia Extramedulary hematopoiesis
64
Cardiophrenic angle mass DDx
Epicardial fat pad Morgani hernia
65
Which cardiac chamber does not contribute to cardiac borders on PA CXR?
Rt ventricle
66
Chamber making the anterior and posterior borders of heart on lateral CXR
Ant: Rt ventricle Post: left atrium and left ventricle
67
Which pathologies can arise in all 3 parts of mediastinum? (Ant., post., middle)
Lymphoma Lung cancer Aortic aneurysm Vascular anomalies Abscess Hematoma
68
Posterior border of middle mediastinum on lateral Xray
A line 1 cm posterior to the anterior border of the thoracic vertebral bodies
69
Cardiothoracic ratio definition
Greatest transverse dimension of the central shadow relative to the greatest transverse dimension of the thoracic cavity Abn if > 0.5
70
Cardiothoracic ratio in pectus excavatum
> 0.5
71
Pericardial effusion on chest x-ray
Globular heart Loss of indentation on the left mediastinal border
72
RA enlargement on CXR
Increase in curvature of Rt heart border Enlargement of SVC
73
Left atrium enlargement on CXR
Straightening of left heart border Increased opacity of lower right side of cardiovascular shadow (double heart border)
74
RV enlargement on CXR
Elevation of cardiac apex from diaphragm Loss of retrosternal airspace Increased contact of right ventricle against sternum
75
LV enlargement on CXR
Rounding of cardiac apex Displacement of left cardiac border leftward, inferiorly and posteriorly
76
Central venous catheter place
Tip: proximal to Rt atrium (in a zone demarcated superiorly by anterior first rib end and clavicle amd inferiorly by top of RA If monitoring CVP: catheter tip must be proximal to venous valves Course parallel to SVC
77
ETT on CXR
Progressive gaseous distention of stomach: esophageal intubation Tip: 4 cm above carina Maximum inflation diameter < 3 cm Diameter of balloon < tracheal diameter above and bellow
78
Nasogastric tube
Tip and sideport: distal to LES, proximal to gastric pylorus Must radiographically confirm tube
79
Swan-Ganz catheter
Tip: right or left main pulmonary arteries or in one of their large lobar branches
80
Chest tube on CXR
In dorsal and caudal portion of pleural space to evacuate fluid In ventral and cephalad portions of pleural space to evacuate pneumothoraces
81
Abdominal xray not useful in evaluating:
GIB Chronic anemia Vague GI Sx
82
Mucosal folds in small vs large bowel xray
S: uninterrupted valvulae connivents (plicae circularis) L: interrupted haustra. Extend only partly across lumen
83
Maximum diameter of small vs large bowel on xray
3 cm L: 6 cm (9 in cecum)
84
Maximum fold thickness in small vs large bowel xray
S: 3 mm L: 5 mm
85
How long after surgery is there intraperitoneal air on x-ray
10 d
86
Small amounts of fluid on abdominal x-ray
Increased distance between lateral fat stripes and adjacent colon
87
Large amounts of fluid on abdominal x-ray
Diffuse increased opacification on supine film Bowel floats to standard of interior abdominal wall
88
Coffee bean projecting to right or mid-upper abdomen
Sigmoid volvolus
89
Dilated loop projecting to left or mid-upper abdomen
Cecal dilation
90
Corkscrew sign on plain film
Small bowel volvolus
91
Toxic megacolon on x-ray
Dilatation of colon > 6.5 cm ``` Mucosal changes: Foci of edema Ulceration Pseudopolyps Loss of normal haustral pattern ```
92
Bowel wall thickening on xray
Increased soft tissue density in bowel wall Thumb printing Stacked coin appearance
93
Extraluminal air on abdominal xray, intraperitoneal
Air under diaphragm in upright film Air between liver and abdominal wall on left lateral decubitus film Supine: gas outlines of structures not normally seen: Rigler’s sign: inner and outer bowel wall Falciform ligament Football sign: peritoneal cavity
94
Extraluminal air on abdominal xray, retroperitoneal
Increased visualization of psoas shadow and renal shadow | Gas outlining retroperitoneal structures
95
Pneumatosus intestinalis on abdominal xray
Linear/rounded Air streaks in bowel wall
96
Mottled, localized, loculated air in abnormal position without normal bowel features
Abscess
97
Air-fluid level onbabdominal xray
Intraluminal wall
98
Air centrally over liver
Biliary
99
Air peripherally over liver in branching patern
Portal vein
100
DDx of intramural air
Linear: Ischemia Necrotizing enterocolitis Rounded/cystoid: Primary Secondary to COPD
101
DDx of portal vein air
Bowel ischemia/infarction
102
Caliber of bowel loops in adynamic vs mechanical obstruction
Adynamic: Normal or dilated Mechanical: Usually dilated
103
Air-fluid level in adynamic vs mechanical obstruction
Adynamic: same level in the same loop Mechanical: Multiple air-fluid levels (step ladder) Dynamic Steing of pearls
104
Distribution of bowel gases in adynamic vs mechanical obstruction
Adynamic: Air throughout GI tract is generalized or localized If localized, dilated sentinel loop remains in the same location on serial films Mechanical: Dilated bowel up to the point of obstruction. No air distal to the obstructed segment Hairpin turns in bowel (180°)
105
The best imaging choice for finding the cause of bowel obstruction
CT
106
Indications for CT colonoscopy
Surveillance in low-risk pt Incomplete colonoscopy Staging of obstructing colonic lesions
107
Imaging helpful in differentiating common benign hepatic hemangiomas from primary liver tumors and metastases
MR
108
Methods for liver elastography
U/S (fibroscan) MRI (MR elastography) (Quantify liver fibrosis)
109
Findings on portal HTN imaging
Increased portal vein diameter Collateral veins Splenomegaly > 12 cm Portal vein thrombosis Recanalization of the umbilical vein
110
U/S findings in liver cirrhosis
Nodular, hyperechoic liver Irregular areas of atrophy of Rt lobe Hypertrophy of the caudate or left lobes
111
Fatty liver infiltration on CT
Hypodense
112
If a lesion in liver is identified via U/S, what’s the next step?
CT (non-contrast, arterial, venous, delayed) or MRI
113
4 phase liver CT helps to R/O:
Hemangioma
114
Hepatic adenoma on U/S
Well-defined Hyperechoic areas (hemorrhage)
115
Hepatic adenoma on CT
Well-defined Hypervascular Enlarged central vessel (isoattenuating in venous phase)
116
Hemangioma on U/S
Homogenous hyperechoic mass
117
Hemangioma CT
Peripheral globular enhancement in arterial phase Central filling and persistent enhancement on delayed scans
118
Focal nodular hyperplasia on U/S
Well-defined Central scar (in 50% of cases)
119
Liver FNH on CT
Hypervascular in arterial phase Isoattenuation to liver in portal venous phase
120
Liver abscess on U/S
Ill-defined Irregular margin Hypoechoic contents
121
Liver abscess CT
Low attenuation Irregular enhancing wall
122
Hydatid cyst on U/S
Simple/multiloculated cyst
123
Hydatid cyst on CT
Low attenuation Simple/muliloculated Calcification
124
HCC on U/S
Single/multiple mass Or Diffuse infiltration
125
HCC on CT
Hypervascular Enhances in arterial phase Washes out in venous phase Portal venous tumor thrombus
126
Liver mets on U/S
Multiple Variable echotextures
127
Liver mets on CT
Low attenuation
128
The purpose of nuclear medicine scan for spleen
To distinguish ectopic splenic tissue from enhancing tumors
129
Pancreas tumor on ultrasound
More ecogenic than normal pancreatic tissue
130
Liver versus spleen density on CT
Liver in denser If not: suspect fatty infiltration
131
Test of choice for diagnosis of cholelithiasis
U/S
132
Most sensitive sonographic findings in acute cholecystitis
Presence of gallstones Sonographic Morphy’s sign Other findings: Thickened gall bladder (>3mm) Pericholecystic fluid Dilated gallbladder
133
Best imaging modality for Dx of acute cholecystitis
U/S HIDA can diagnose cases of acalculis or chronic cholecystitis
134
Best imaging modality for appendicites
U/S Or CT
135
Appendicitis on U/S
Thick-walled Appendicolith dilated/fluid filled Non compressible
136
Appendicitis on CT
Enlargement (>6 mm) in outer diameter Enhancement of the wall Adjacent inflammatory stranding Appendicolith Helps percutaneous abscess drainage
137
Best imaging modality for diverticulitis
CT (with oral and rectal contrast)
138
CT findings in diverticulitis
Thickened wall Mesenteric infiltration Gas-filled diverticula Abscess Also used to guide abscess drainage
139
Imaging modality used for screening and follow up of acute pancreatitis
U/S
140
First line imaging test for assessment of complications in acute pancreatitis
CT
141
U/S findings of acute pancreatitis
Hypoechoic Enlarged Gas obscures pancreas if qileus present
142
CT findings of acute pancreatitis
Enlarged Edema Stranding in surrounding fat Indistinct fat planes Mesenteric and Gerota thickening Pseudocyst in lesser sac Abscess Necrosis Hemorrhage Also used for needle aspiration/drainage of abscess F/U of pseudocyst
143
Pancreatic necrosis on CT
Low attenuation Gas-containing Non-enhancing
144
Best imaging modality for chronic pancreatitis
MRCP
145
MRCP findings in chronic pancreatitis
Calcification Duct obstruction Duct dilatation Enlargement of pancreas Fluid collection adjacent to gland (pseudocyst)
146
The amount of bleeding needed to be visualized by angiography
Optimal: 1-1.5 ml/min
147
Standard imaging for renal masses
Renal triphasic CT Unenhanced Arterial and venous Excretory
148
Indications of CT urography
Microscopic/gross hematuria Detailed assessment of urinary tracts Uroepithelial malignancies of the upper urinary tract
149
Indications of MRI over CT for urologic evaluation
Previous nephron sparing surgery Requiring serial follow up Reduced renal function Solitary kidney Clinical staging of prostate cancer
150
Indications for VCUG
Children with recurrent UTI Hydronephrosis Hydroureter Suspected lower urinary tract obstruction Vesicoureteral reflux
151
Renal scans to assess anatomy, scar, pyelonephritis
Tc-DMSA Tc-glucoheptonate
152
Renal scans to assess renal function and collecting system
Tc-pentetate (DTPA) Mertiatide (MAG3)
153
Initial investigation for pelvic pathology
Transabdominal U/S
154
Polyps on U/S
Well-defined Homogenous Isoechoic to the endometrium Preservation of the endometrial-myometrial interface
155
Atypical polyp features on ultrasound
Cystic components Multiple polyps Broad base Hypoechogenicity Heterogeneity
156
Typical leiomyoma on U/S
Well defined Broad-based Hypoechoic Solid Shadowing The overlying layer of endometrium is echogenic and distorts the endometrial-myometrial interface
157
Atypical features of leiomyoma on ultrasound
Pedunculation Multilobulated surface
158
Endometrial hyperplasia and cancer on ultrasound
Diffuse echogenic endometrial thickening without focal abnormality Early cases can be focal and appear as a polypoid mass
159
Uterine adhesions on ultrasound
Mobile Thin Echogenic bands Cut across the endometrial cavity
160
Atypical features of uterine adhesions on ultrasound
Thick Broad-based Completely obliterate the endometrial cavity (As in Asherman)
161
Adrenocortical adenoma on CT
<3 cm Smooth Round/oval Homogenous Not highly vascular >50% washout of contrast medium on CT at 10 min Stable or very slow growth (<1 cm/yr) Low density MRI T2: isointense in relation to liver
162
Adrenocortical carcinoma on CT
> 4 cm Irregular Unclear margins Heterogenous with mixed densities Usually vascular <50% washout at 10 min Rapid growth (>2 cm/yr) Necrosis Calcification Hemorrhage MRI T2: hyperintense in relation to Liver
163
Pheo on CT
> 3 cm Round/oval Clear margins Heterogenous with cystic areas Usually vascular < 50% contrast washout at 10 min ``` Slow growth (0.5-1 cm/ yr) Hemorrhage ``` MRI T2: markedly hyperintense in relation to liver
164
Adrenal mets on CT
< 3 cm Oval/irregular Heterogenous Mixed density Usually vascular <50 % washout Variable growth Hemorrhage MRI T2: hyperintense in relation to liver
165
Area of brain that can be obscured by bony-related artifact
Posterior fossa
166
Screening tests for assessment of SAH
CTA | MRA
167
SPECT
Assesses cerebral blood flow and cellular metabolism Using: Tc-exametazime Tc-bicisate Taken up predominantly in gray matter Diffuse rapidly across the BBB and become trapped within neurons (proportionate to cerebral blood flow)
168
FDG PET
Assesses cerebral metabolic activity
169
Indications of FDG PET
Differentiating residual tumor from radiation necrosis Localizing epileptic seizure foci Evaluation of atypical dementia
170
Increased thickness of dura may suggest
Presence of blood
171
Poor contrast between white and gray matter suggests:
Possible infarction, edema, tumor, infection, contusion
172
Central gray matter nuclei not visible:
Infarction Tumor Infection
173
Hyperdensity in parenchyma suggests
Enhancing lesion Hemorrhage Calcification
174
Imaging after Sx of stroke
1st non-contrast CT If negative: MRI with diffusion weighted sequence or CTA
175
Best imaging modality for brain infarct
MRI
176
Brain infarction findings on CT (0-24 h)
Normal within 6 h ``` Edema: Loss of gray-white diff Insular ribbon sign Effacement of sulci Mass effect ``` Hyperdense MCA sign: Thrombosis, emboli If hemorrhagic: Hyperattenuating acute blood, surrounded by edema
177
Brain infarction findings on CT (24h-1wk)
Increasing edema: Hypoattenuation Mass effect
178
Brain infarction findings on CT (1-3wk)
Resolution of edema, therefore increased attenuation of infarcted area: Near-normal density, may mask stroke (fogging phenomenon)
179
Brain infarction findings on CT (>3wk)
Encephalomalacia (parenchyma volume loss): | Hypoattenuation with negative mass effect
180
Brain infarction findings on MRI (0-24 h)
DWI: Hyperintense within minutes ADC: Hypointense within minutes T2/FLAIR: Hyperintense 6 h after onset
181
Brain infarction findings on MRI (24h-1wk)
DWI: Hyperintensity ADC: Hypointensity T2/FLAIR: Hyperintensity
182
Brain infarction findings on MRI (1-3wk)
DWI: Hyperintensity ADC: Continues rising. Hyperintensity at 10-15 d T2/FLAIR: Hyperintensity
183
Brain infarction findings on MRI (>3wk)
DWI/T2/FLAIR: Hyperintensity progressively decreases ADC: Remains elevated
184
Best imaging modality for carotid artery disease
Duplex doppler U/S
185
If plan to perform carotid angioplasty or endarterectomy, next imaging?
MRA or CTA If inadequate, then: Conventional angio
186
Best imaging modality and its sensitivity and specificity for MS
MRI High sensitivity Low specificity
187
MRI findings in MS
Cerebral or spinal plaques ``` Areas: Periventricular Corpus callosum (at right angle) Centrum semioval Deep white matter Basal ganglia Dawson’s fingers Perivascular/interstitial edems ``` Ovoid Hyperintense on T2 Hypointense on T1 Spinal: Hyperintense lesion on T2 (at least 3 mm but less than 2 vertebral segments) Occupy only part of the cord on cross-section Focal, clearly delineated and circumscribed on T2 Little or no cord swelling
188
Best imaging modality for meningitis
MRI T2: Meningeal enhancement Hydrocephalus Subdural effusion Cerebral swelling
189
Sites of herpes simplex encephalitis
``` Limbic regions: Temporal lobe Orbitofrontal region Insula Cingulate gyrus ```
190
Best imaging modality for HSV encephalitis
MRI T1 and T2 T2: High intensity lesions on T2 MRI in temporal and inferior frontal lobes
191
CT findings of HSV encephalitis
Low density in temporal lobe and insula Rarely basal ganglia involvement
192
Best imaging modality for brain abscess or cerebritis
MRI ``` Early cerebritis(1-3d): Low intensity on T1 High intensity on T2 ``` ``` Late cerebritis(4-9d): Ring enhancement ``` Early capsule(10-13d): ring Late capsule(14 d or greater): ring, considerable edema around
193
Indications for bone CT
Complex, comminuted, intra-articular, occult fx including: Distal radius Scaphoid Skull Spine Acetabulum Calcaneus Sacrum
194
Indications for MRI of musculoskeletal system
Internal derangement of joints (ligaments, capsule, menisci, labrum, cartilage) Tendons Muscles Bony masses
195
Indications for musculoskeletal U/S
Tendon injury Detection of soft tissue masses, Cystic or solid Foreign body Guide for Bx, injection Doppler for vascularity
196
Bone scintigraphy
Tc-Methylene Determines the location and extent of bony lesions. Areas with increased turnover/calcification: ``` Growth plates Tumors Infections Paget Fx Reactive bone formation Periostitis ```
197
Osteoarthritis on Xray
Joint space narrowing (non-uniform) Subchondral sclerosis Subchondral cyst formation Osteophytes
198
RA on Xray
Uniform joint space narrowing Soft tissue swelling Erosions Periarticular osteopenia
199
Most common bone tumors by age
<1 y: Metastatic neuroblastoma 1-20 yr: Ewing 10-30: Osteosarcoma >40: Mets, MM, chondrosarcoma
200
DDx of multiple bone tumors
Mets Myeloma Lymphoma Fibrouse dysplasia Enchondromatosis
201
Epiphysis bone lesions
Giant cell tumor Chondroblastoma Geode Eosinophilic granuloma Infection
202
Metaphysis bone lesions
Simple bone cyst Aneurysmal bone cyst Enchondroma Chondromyxoid fibroma Non-ossifying fibroma Osteosarcoma Chondrosarcoma
203
Diaphysis bone lesions
Fibrous dysplasia Aneurysmal bone cyst Brown tumor Eosinophilic granuloma Ewing
204
Expansile bone lesions
Aneurysmal bone cyst Giant cell tumor Enchondroma Brown tumor Mets Plasmacytoma
205
Bone matrix mineralization types
Chondroid (popcorn calcification) Osseous
206
Characteristics of benign bone tumors
Thin sclerotic margin Sharp delineation No or simple periosteal reaction No soft tissue mass
207
Characteristics of malignant bone lesions
Poor delineation Wide zone of transition Loss of overlying cortex Bony destruction Periosteal reaction Soft tissue mass
208
DDx of Codman’s triangle
Osteosarcoma Ewing Subperiosteal abscess
209
Onion skin periosteal reaction
Ewing
210
Sunburst periosteal reaction
Osteosarcoma
211
Hair on end periosteal reaction
Osteosarcoma
212
Imaging modality of choice for osteomyelitis
MRI
213
When are plain film changes visible in osteomyelitis?
After 8-10 d: Soft tissue swelling Local periosteal reaction Pockets of air (if anaerobes or necrotizing fasciitis) Mottled and non-homogenous appearance (moth-eaten) Cortical destruction
214
Benign lesions which may have aggressive features on imaging
Osteomyelitis Osteoblastoma Aneurysmal bone cyst LCH Myositis ossificans
215
Bone abscess imaging
Sharply outlined Radiolucent Variable thickness in zone of transition Sequestrum Sinus tract or cloaca to the skin surface
216
Best imaging for diagnosis of bone abscess
MRI: bone, bone marrow, soft tissue CT: sequestra, cortical erosion
217
Gold std for measuring BMD
DEXA Z-score: SD from the age-matched mean T-score: SD from young adult mean (most clinically valuable)
218
Codfish vertebra (biconcave) seen in
Osteoporosis
219
Long bone osteoporosis on xray
Thinned cortex Increased medullary cavity
220
DDx of osteopenia on Xray
Osteoporosis Osteomalacia Hyperpara Disuse
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Xray of osteomalacia/rickets
Initial osteopenia (coarse and poorly defined bone texture) Fuzzy, ill-defined trabeculae Looser’s zones (pseudofracture): fissures and clefts at right angle to the bone
222
Hyperparathyroidism on Xray
Ca deposit in hyaline cartilage or fibrocartilage Resorption of bones in hands (subperiosteal and at tufts) Resorption at sacroiliac joints (subchondral) Resorption at skull (salt and pepper) Osteoclastoma (brown tumor) Rugger jersey spine: band-like sclerosis at superior/inferior margins of vertebral bodies
223
Paget’s disease onnXray
Esp: skull, spine, pelvis 1st phase: lytic 2nd phase: mixed 3rd phase: sclerotic Coarsening of trabeculae with bone expansion Bone softening/bowing High activity on bone scan, esp at bone ends Thickened cortex
224
Indications of SPECT
Dementia Traumatic brain injury Vasculitis Neuropsychiatric disorders Stroke Confirming brain death Seizure (determining the epileptogenic focus)
225
PET indications
Dementia Grade and stage of brain tumor Sizure imaging Vasculitus Alzheimer (amyloid tracing)
226
Indication for intrathecal In-DTPA
CSF leak Differentiation between NPH and brain atrophy
227
MIBG in dementia
If decreased MIBG activity in heart = autonomic impairment = Lewy body dementia, Parkinson
228
False negative thyroid RAIU
Recent radiographic contrast study High dietary iodine (seaweed, thyroid vitamin)
229
Thyroid RAIU is index of:
Thyroid function I 131 Useful for differentiation of hyperthyroidism in adults, and also hypothyroidism in children
230
Thyroid imaging
Tc-pertechnetate Radioactive iodine (I 123) Functional anatomic detail
231
Results of scintiscan of thyroid
Hot nodule Cold nodule: cancer must be considered Isointense (warm) nodule: cancer must be considered
232
Radioiodine thyroid ablation
I 131 Remain away from family members and care givers No pregnancy for 6 mo Risk of: Exophthalmus Thyroid storm Secondary malignancy
233
DDx of ventilation scan defect
Airway obstruction Chronic lung disease Bronchospasm Tumor obstruction
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Perfusion scan contraindications
Relative: Severe pulmonary HTN Rt to Lt shunt Previous Hx of pneumonectomy Small child
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Indications of V/Q scan in PE
Pregnancy CT contraindicated
236
Abn V/Q test:
Ventilation present but perfusion absent
237
When is V/Q scan not valid?
Consolidation Ventilatory problems (use modified V/Q scan which is perfusion only) Modified scan also suitable for pregnancy if CXR is nl and there are no ventilatory problems
238
DDx of perfusion scan defect
Reduced blood flow COPD Asthma Bronchogenic carcinoma Inflammatory lung disease Pneumonia Sarcoidosis Mediastinitis Mucous plug Vasculitis
239
Indications for myocardial perfusion scanning
To investigate coronary artery disease To assess treatment of CAD Preop risk stratification Viability testing
240
Myocardial perfusion scanning in patients with left bundle
Given pharmacologic stress (persantine vasodilator)
241
Contraindications to pharmacologic stress
sBP <90 Asthma
242
Myocardial perfusion scan in patients with asthma who cannot exercise
Give dobutamin
243
Interpretation of myocardial perfusion scan
Persistent defect at rest and stress: Suggest infarction or myocardial scar ``` Reversible defect (only during stress): Ischemia ``` Patience with >10% ischemic myocardium benefit most from revascularization
244
Radionuclide ventriculography purpose
Provides information about RV function, presence of shunts
245
Cardiac MUGA scan
Sums multiple cardiac cycles Evaluates: LV function, regional wall motion, ejection fraction, diastolic dysfunction, ventricular volume
246
Indications of radionuclide ventriculography/MUGA
To monitor potential cardiac toxicity with chemotherapy or Herceptin Gold standard for ejection fraction in defibrillator work up
247
HIDA scan
Cholescintigraphy Prefer NPO after modnight (but could be non-fasting state)
248
Interpretation of HIDA
Acute cholecystitis: No visualization of gallbladder at 4 h No visualization of gallbladder at 1 hr after administration of morphine Chronic cholecystitis: No visualization at 1 h, but seen at 4 h, or seen after morphine injection
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Gallbladder normal ejection fraction
>38%
250
Effect of fasting on HIDA
Fasting < 4 h or > 24 can make test abnormal (obstruction)
251
RBC scan
Active GIB < 0.5 ml/min Liver hemangioma: Cold early Fills in later
252
Nuclear scan for meckel
M pertechnetate after ranitidine premedication | Meckel lights up as the stomach
253
Nuclear scan for neuroendocrine tumors ( carcinoid, gastrinoma, insulinoma)
In-octreoscan (somatostatin analogue) Gastrinoma and carcinoid are more octreotide avid than insulinoma
254
Tc DTPA orTc MAG3 renal scan
Renal function and anatomy UPJ obstruction Assess renal transplant Kidney donation
255
Tc DMSA
Pyelonephritis in children Reflux (injection into bladder)
256
Bone scan shows
Increased blood supply to bone Or High bone turnover Indications: Bone pain of unknown origin Tumor staging Arthroplasty complications Osteomyelitis
257
DDx of positive bone scan
``` Mets Primary bone tumor Arthritis Fx Infection Anemia Paget ```
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Lytic lesions on bone scan
Normal or cold (false negative) Examples: MM RCC Eosinophilic glanuloma
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Superscan
Increased bone uptake + poor renal uptake DDx: Diffuse mets Renal osteodystrophy
260
Most common indication of thrombolytic therapy
Treatment of ischemic limb
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Tumors amenable to RF ablation
HCC, hepatic mets Renal tumors
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Indications for central vein access
Fluid AB TPN Chemo Blood Blood sampling
263
Indications for breast cancer screening by mamo
From age 50 q 2-3 yr >70 yr, if in good general health <50 if high risk
264
Other indications of mamo
F/U of women with previous breast cancer Lump/thickening, Nodularity Dimpling Contour deformity Persistent focal pain Spontaneous discharge from a single duct (serous, sanguinous) Abn screening mammo Complications of breast implants
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Mammo report: Probably benign, likelihood of malignancy <2% Next step?
Unilateral mammo at 6 mo
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Mammo report: Suspicious abnormality Next step?
Bx
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Mammo report: Highly suspicious of malignancy, likelihood: 95%
Bx
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Mammo report: Negative or normal
Routine screening
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Mammo report: | Incomplete
Additional imaging Comparison to prior films
270
Indication of breast U/S
Palpable abnormalities in: <30 yr Lactating Pregnant Further characterization of mammo findings Guide for interventions
271
Breast MRI indications
For Dx, after indeterminate mammo and U/S. “Problem solving” For screening in high-risk pts, in conjunction with mammo. Suspected silicone implant rupture/problems Evaluation of previous breast cancer for: margins, recurrence, response to chemo...
272
High-risk pts for breast cancer
Known BRCA1 and BRCA2 mutation Known other gene predisposing to breast cancer Untested 1st degree relative of a carrier of such mutations FHx of hereditary breast cancer syndrome Estimated personal life-time cancer risk >25% High risk marker on prior Bx: Atypical ductal hyperplasia Atypical lobular hyperplasia Lobular carcinoma in situ RT to chest before 30
273
Breast mass vs breast asymmetry
Mass: space-occupying lesion seen in 2 different projections Asymmetry: seen only in a single projection
274
Benign breast mass on mammography
Oval/round/lobular Circumscribed/well-defined margin Radiolucent ``` Calcifications: Popcorn (hyalinizing fibradenoma) Lucent centered Layering (milk of Ca) Vascular Round Scattered ```
275
Mammographic features of malignant breast lesion
Irregular shape Indistinct, microlobulated, spiculated margin Radiodense ``` Calcification: Pleomorphic Amorphous Fine linear Coarse heterogeneous Regional Segmental Clustered ```
276
Significance of tubular density/dilated ducts
Of little concern
277
Typical Intramammary lymph nodes
Circumscribed Reniform Fatty notch and centre (particularly important) < 1cm Outer upper part of breast If all seen: benign
278
Focal asymmetry on mammo, next step?
Must be carefully evaluated with focal compression Bx if: The area can be palpated Or Focal compression shows mass-like character

Med (25 decks)

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