Radiography vs. ultrasonography-which one to use to make the diagnosis (Proceedings)

Indications for Radiographic Examination

• Overview

• Size, shape, position, contour, opacity

• Very good for bone and gas-skeletal system, lungs

• Contrast studies-GI series, IVU, cystourethrogram, vaginogram enhance ability to define structures.

• Can only see four opacities-gas, fat, bone and "soft tissues"

• Need one opacity surrounding something of a different opacity to be able to define it radiographically

Indications for Ultrasound Examination

• Individual soft tissue organ composition

• Dynamic blood flow

• Not so good for bone and gas

Abdominal Cavity

a. Method Of Choice For Detecting Etiology For Peritoneal Fluid.

1. Fluid Acts As "Acoustic Window/Contrast Medium" Which Help Visualization Of Intra-Abdominal Structures.

2. Abdominal Masses Can Be Assessed Despite The Presence Of Hemorrhage.

b. Liver Can Be Evaluated, Espeically Its Architecture And

c. Contour.

1. Focal Lesions-Metastasis, Nodular Hyperplasia.

2. Mass Lesions-Abscess, Cysts, Neoplasia

3. Hepatic Congestion

4. Vascular Abnormalities-Shunts, Av Fistula

5. Cirrhosis

d. Hepatobiliary System-Indicated In Presence Of Jaundice

1. Cholelithiasis

2. Extra-Hepatic Biliary Obstruction, Enlarged Common Bile Duct

3. Enlargement Of Intrahepatic Bile Ducts

4. Neoplasia Involving Biliary System

5. Obstruction Due To Pancreatic Disease

e. Spleen-Indicated In Presence Of Splenomegaly And Blood Dyscrasias

1. Torsion

2. Neoplasia

3. Nodular Hyperplasia

4. Infection

5. Infarction

6. Hematoma

f. Urogenital System

1. Pregnancy Diagnosis 10-25 Days Post-Breeding

2. Fetal Viability

3. Ovarian Masses, Cysts

4. Infertility

5. Pyometra/Hematometra

6. Ovarian Pedicle And Uterine Stump Pyogranuloma

7. Scrotal Enlargement-Neoplasia, Hydrocele

8. Location Of Retained Testicle

9. Prostate Gland-Hyperplasia, Cysts, Abscesses, Neoplasia

10. Kidneys-Neoplasia, Cysts, Abscesses, Hydroureteronephrosis, Glomerulonephrosis/ Nephritis, Mineral Deposition/Calculi, Toxicosis, Fibrosis, Hypoplasia/Dysplasia

11. Urinary Bladder-Neoplasia, Infection, Neoplasia, Wall Thickness

g. Other

1. Pancreas-Neoplasia, Pancreatitis

2. Adrenal Glands-Hyperplasia, Neoplasia

3. Gastrointestinal Tract-Neoplasia, Intussusception, Infiltrative Diseases

4. Lymph Nodes-Mesenteric, Retroperitonel Enlargement

5. Peritoneum-Carcinomatosis, Mesenteric Masses

6. Retroperitoneum-Effusion, Hemorrhage, Lymph Node Enlargement

7. Hernia-Diaphragmatic, Pericardial-Peritoneal, Body Wall

8. General Abdominal Survey

Thoracic Cavity

a. Method Of Choice When Pleural Fluid Is Present

b. Heart

1. Cardiomyopathies – Dilated, Hypertrophic

2. Acquired Diseases – Mitral Insufficiency, Endocardiosis, Endocarditis

3. Neoplasia-Heart Base, Right Atrial

4. Thrombus

5. Congenital Diseases – Pda, Septal Defects, Pulmonic And Arotic Stenosis, Valve Dysplasia

6. Evaluate Response To Therapy

c. Pericardial Disease-Masses, Fluid, Thickness

d. Mediastinum-Neoplasia, Abscesses

e. Lymph Nodes

f. Lung Masses When Adjacent To Thoracic Wall Or Diaphragm

g. Pleural Masses

h. Heartworm Disease

Comparison – Ultrasonic Image To Radiographic Image

Miscellaneous

a. Ocular

1. Evaluate Internal Ocular Structures In Presence Of Hemorrhage Or Corneal Scarring

2. Retinal Detachment

3. Lens Luxation

4. Intra-Ocular Neoplasia Or Foreign Body

5. Retrobulbar Area – Neoplasia, Abscess, Foreign Body

b. Vascular Structures—Enlargements, Thrombosis, Catheter Localizations, Neoplasia

c. Any Soft Tissue Body Surface Mass – Determine Size Architecture, Invasiveness, Vascularity

d. Retropharyngeal Masses-Neopalsia Thyroid, Lymphadenopathy, Abscesses

Organ Systems And Disease are Defined By Their:

Echogenicity – The Echogenic Composition Of The Tissue And Its Composition Compared To Other Tissues.

• Size

• Shape

• Location

• Contour

• Blood Supply

• Motion

• Distortion Of Adjacent Tissues

Echogenic Scale Of Organ Systems From Black To White

Diagnostic Ultrasound: Key Terms

Echogenicity – Refers To The Amount Of Sound Returned To The Transducer From An Object And/Or Interface

• Low Echogenicity –Minimal Amount Of Sound Returned

• High Echogenicity –Maximum Amount Of Sound Returned

Anechoic Without Sound

Hypoechoic Lesser Amount Of Sound

Isoechoic Similar Amount Of Sound

Hyperechoic Greater Amount Of Sound

For Routine B Mode Ultrasound, The Convention Used Is To Have The Screen Black And Any Sound Detected Is Displayed

As A White Dot; Using This Convention.

Anechoic – Meaning Without Sound – Is Displayed As BLACK

Hyperechoic – Meaning With A Greater Amount Of Sound – Is Displayed As WHITE

Isoechoic – Meaning A Similar Amount Of Sound – Is Displayed As The SAME COLOR

Hypoechoic – Meaning With A Lesser Amount Of Sound – Is Displayed As DARKER