Hips for AVN (8.01.08)
 


3-PLANE LOCALIZER Calibration Scan BH AXL T1 BILAT AXL IR BILAT HIPS COR IR BILAT HIPS COR T1 BILAT SAG PD HIP (affected)
IMAGING PARAMETERS
Plane
3-PLANE AXIAL AXIAL AXIAL CORONAL CORONAL SAGITTAL
Mode
2D 2D 2D 2D 2D 2D 2D
Pulse Seq
Fiesta Gradient Echo FSE-XL IR IR FSE-XL FSE-XL
PSD Name
-- -- -- -- -- -- --
Imaging Options
Seq Fast Fast Calib FC NPW TRF Fast ZIP512 FC NPW Seq TRF Fast NPW Seq TRF Fast FC NPW TRF Fast ZIP512
NPW TRF Fast ZIP512
SCAN TIMING
# of Echoes
1 1 1 1 1 1 1
TE
Minimum
-- Min Full 130.0 130.0 Min Full 17.0
TR
--
-- 650.0 3000.0 6000.0 650.0 2000.0
Flip Angle
45 -- -- -- -- -- --
Bandwidth
125.00
-- 20.83 31.25 31.25 20.83 25.00
ADDITIONAL PARAMETERS (see attached instructions)
SAT
             
ACQUISITION TIMING
Freq
256
-- 256 256 256 256 256
Phase
128 --
192 192 192 192 192
NEX
1.00
-- 2.00 3.00 3.00 2.00 2.00
Phase FOV
1.00 -- -- -- -- -- --
Locs Before Pause
0 -- 0 0 -- 0 --
Freq Dir
Unswap A/P A/P A/P R/L S/I A/P
Auto Center Freq
             
Auto Shim
Auto Auto Auto Auto Auto Auto Auto
Contrast
No No No No No No No
SCANNING RANGE
FOV
48.0 48.0 40.0 30.0 30.0 40.0 20.0
Slice Thickness
5.0 8.0 6.0 6.0 6.0 6.0 4.0
Spacing
5.0
0.0 1.0 Intleave 0.0 0.0 1.0
Start - End
             
# of Slices
-- 45 20 20 14 20 --
Scan Time
             
 
 

Scheduling Guidelines

                        or         MRI pelvis with Gd      60 minutes

 

 

      1)      Is there a mass or tumor?______ When did you first discover the mass?_______________________

      2)      Does the problem relate to a recent injuring?  YES   NO    DATE_____________________

      3)      Where does the hip hurt (  FRONT  -  BACK  -  INSIDE  -  OUTSIDE  )?

      4)      Have you had surgery on your hip or pelvis?   YES   NO    DATE__________________________

      5)      Have you had an x-ray?  

 

   

Patient Preparation:

 

Coil: Torso array

Patient Positioning:  Supine, feet first,

Landmark: Pubic symphysis

 

Series 1: Locator

 

This high quality locator is designed to screen the pelvis for masses that may cause symptoms referrable to the hip. It

is performed as an interleaved acquisition so that half of the images will be available half-way through the scan to use

for proscribing the next series. By landmarking on the pubic symphysis it will automatically cover nearly all the way to

the top of the iliac crests. However in large patients it may be useful to increase the slice thickness. Try to stick to 20

images total so that they will all fit on a 20-on-1 sheet of film

 

 

 

Series 2: Coronal T1

 

Coronal T1 helps to define the anatomy. It should be prescribed in a similar distribution as Series 2. The combinationof

this with series 1 and 2 helps to define the percentage of the femoral head involved with osteonecrosis. Less than 25%

and it is left alone to heal but with greater than 50% involvement femoral head collapse is common espcially if weight

bearing cannot be avoided.

 

 

 

 

 

 

Series 3: Coronal T2 Fat Sat/STIR

 

This sequence is prescribed to include sacro-iliac joints posteriorly to the anterior acetabulum. An alternative sequence

with similar contrast is FSE T2 with fat saturation. T2 may have slightly higher spatial resolution but may be degraded

in the setting of magnet field inhomogeneity which can interfere with fat saturation.

 

 

 

 

 

Series 4: 3D Cartilage (optional)

 

Examinination of the cartilage with this sequence is important in the event that osteoarthritis or other arthropies are

expected. The volume of coverage should include from above the acetabulum to belowe the greater trocantor.

 

 

 

 

Filming Instructions:

 

series 1: 20-on-one

series 2: 15 on one

series 3: 15 on one

series 4: 12-on-one of selected reformations in axial, coronal and sagittal planes

 

 

Billing Instructions:

 

 

 

 

ICD9 Codes:

 

osteonecrosis

hip pain

osteomyelitis

fracture

stress fracture

tumor

effusion

developmental dysplasia

osteoarthritis

 

 

Sample Normal Dictation:

 

Technique: Axial T1, Coronal STIR, Coronal T1 and 3D SPGR fat sat for cartilage.

 

 

 

Findings: The left hip is normal with normal allignment and no evidence of osteonecrosis, osteoarthritis, occult fracture,

tumor or other osseous abnormality. This is no significant hip joint effusion.

 

 

 

The right hip joint has a moderate effusion. On T1 there is a serpigenous low signal rim surrounding a T1 bright center

involving approximately 25% of the femoral head. It involves primarily the (medial, central or lateral) aspect of the

femoral head where is (is not) significant weight bearing. On STIR there is a bright peripheral rim with central T2

darkness and a double line sign which is also characteristic of AVN in the acute phase. The femoral contour remains

rounded with no evidence of flattening or collapse at this point. The AVN is categorized as (A,B,C or D) based on the

central signal and stage (0,I,II,III,IV,V).

 

 

 

Categorization: A = acute [center is same as fat: T1 bright and STIR/T2 dark]

B = subacute [center contains blood: T1 bright and T2 bright]

C = subacute [center conains fluid: T1 dark and STIR/T2 bright]

D = chronic [center is fibrotic/sclerotic: T1 dark STIR/T2 dark]

 

Staging:

 

0 clinically asymptomatic: MRI may show focal marrow edema (T1 dark, STIR/T2 bright)

I symptomatic:

II symptomatic with large MRI abnormality: T1 decreased but heterogeneous, T2 heterogeneous

III cresent sign on X-ray: MRI show heterogenous signal on T1 and T2

IV flatening of femoral head

V osteoarthritis

 

 

 

The sacro-iliac joints are normal (abnormal).

 

 

 

No pelvic masses are identified.

 

 

 

Impression:

 

 

 

No AVN of left hip