Specialty Imaging PPT Flashcards
What is the name of the procedure that examines the CNS structures situated within the vertebral canal?
Myelogram
Spinal cord and its _______ structures with the
use of contrast
Nerve
Spinal Cord Review
Slender, elongated structure
Adult – 18” to 20” long
***Spinal Cord Extends from
brain (connects to medullaoblongata @ level of
foramen magnum) to space between _1st & 2nd_vertebra
Spinal Cord ends @
L1-L2
Cornus Medullaris
Spinal Cord connects to
31 pairs of spinal nerves
***Spinal Cord Most pathology and trauma occur in the
Cervical & lumbar areas of the spine
Myelograms are used to identify
– Extent
– Size
– Level of pathological process
***Pia mater
Inner sheath; adhere closely to spinal cord
***Subarachnoid space
Wide space separating arachnoid from pia mater
– Continuous with ventricular system of brain
– Ventricles & subarachnoid space contains cerebrospinal fluid
» CSF produced in ventricles
***Arachnoid
Delicate, central sheath
***Dura mater
Outermost sheath
– Strong fibrous covering of brain and spinal cord
***Subdural space
Separates dura from arachnoid space
– Does not communicate with ventricular system
***What are some of the indications for a myelogram?
- Extrinsic spinal cord compression caused by a herniated disk, bone fragment, cyst or tumor (Most common-HNP)
- Spinal cord swelling resulting from traumatic injury
- Identifies narrowing of subarachnoid space
***What are some of the contraindications for a myelogram?
- Blood within CSF
- Arachnoiditis (inflammation)
- Increased intracranial pressure
- Recent lumbar puncture (w/t 2 weeks)
***What contrast agent introduced in late 1970s for myelogram?
Water‐soluble
Nonionic Iodinated
***Nonionic & water‐soluble contrast
– Provide visualization of nerve roots
– Readily absorbed by body
• _4-5_hours hazy effect; undetectable after 24 hours
Nonionic & water‐soluble contrast good enhancement for
CT of spine (follow‐up)
***What type of injection is used for a myelogram?
Intrathecal injection
Store intrathecal injection separate from other contrast
***Where is the contrast for a myelogram commonly injected?
L2-L3 or L3-L4 interspace
Also @ cisterna magna between C1 & occipital bone
Most commonly used contrast agents for myelogram are
– Isovue
– Omnipaque
Using ionic contrast may
cause
Severe & fatal neurotoxic reactions
***Lumbar Myelogram Procedure
Contrast (_9-12 mL) slowly injected • Angulation of table for distributing contrast – Erect to Trendelenburg – Head fully extended -Patient is monitored for 4 to 6 hours • Patient’s head and shoulders elevated 30 to 45 degrees • Bed rest for several hours – Avoid strenuous activity for 72 hours
What are some common complications of a myelogram?
Headache Nausea/vomiting Seizure Allergic reaction Bleeding Infection
Myelogram Demonstrates
– Deformity in subarchnoid space
• Obstruction of passage of contrast within space
Myelogram Conus projection
– Demonstrates conus medullaris
– AP position with CR @ T12‐L1
***What is the name of the procedure for radiography of a joint or joints?
Arthrogram
Radiologic examination of soft tissue structures of joints after injection of 1 or 2 contrast agents into capsular space
– Pneumoarthrography (gaseous)
– Opaque arthrography (water‐soluble iodinated)
– Double‐contrast arthrography (combination)
***MRI
has reduced number of arthrograms
***What are the most frequent sites for an arthrogram to be performed?
Knee & shoulder
Hip, wrist & TMJ
***Images are taken for arthrogram
Fluoroscopy and conventional images
What are some common indications for a knee arthrogram?
- Tears of the joint capsule, menisci or ligatments (trauma)
* Baker’s cyst (nontrauma)
Purpose of knee arthrogram
Demonstrate and assess knee joint &
associated soft tissue
***What are indications for a shoulder arthrogram?
- Evaluation of partial or complete tear in rotator cuff or glenoidal labrum
- Persistent pain or weakness
- Frozen shoulder
***Where is the injection site for a shoulder arthrogram?
- ½ inch inferior and lateral to the coracoid process
* Spinal needle is used due to deep location of capsule
Shoulder Arthrogram Procedure
- Single contrast: 10 to 12 mL of contrast
* Double contrast: 3 to 4 mL of contrast along with 10 to 12 mL of air
Shoulder Arthrogram Projections
– AP (internal/external)
– 30‐degree AP oblique
– Axillary
– Tangenital
Shoulder Arthrogram Increasingly performed with
MRI
– Injection of gadolinium contrast into joint capsule
CT follows double contrast arthrogram
Images obtained @ 5‐mm intervals
Wrist Arthrogram Indications
•– Trauma
– Persistent pain
– Limitation of motion
Wrist Arthrogram Contrast is injected
– Dorsal wrist @ articulation of radius, scaphoid &
lunate
– 1.5 to 4 mL
***Hip Arthrogram
Performed most often on children
– Evaluate congenital hip dislocation before &
after treatment
***If performed on adults
– Detect loose hip prosthesis
– Confirm presence of infection
Cement used to fasten hip prosthesis components
– Barium sulfate added to cement (radiographically visible)
***Use SUBTRACTION technique
Injection site of Hip Arthrogram
¾” distal to inguinal crease & ¾” lateral to palpated femoral pulse
• Spinal needle
***What is the name of the radiologic procedure that examines the nonpregnant uterus, accessory organs and vagina?
HSG
***What are some indications for an HSG?
- Assessment of female infertility
- Size, shape and position of uterus & uterine tubes
- Delinate lesions (polyps, tumor masses or fistulous tracts)
- Patency of uterine tubes
***What are some contraindications for an HSG?
- Pregnancy
- Acute pelvic inflammatory disease
- Active uterine bleeding
***The HSG examination should be scheduled approximately
7 to 10 days after the onset of menstruation.
***What position will be the patient be placed in to facilitate the flow of contrast during an HSG?
Trendenlenburg
LITHOTOMY position
Where should the contrast spill out into when performing an HSG?
Peritoneal cavity
How much contrast is used to fill the uterine cavity and how much is needed to fill the uterine tubes?
4 to 5 ml
Additional 4 to 5 ml for uterine tube patency
