We used 128 slice CT (135 Kv,
400 mA,
slice thickness 1,0 mm and 0,5 mm after reconstruction) in pronation position,
view in bone and soft-tissue window.
In 23% we added in the diagnostics protocol CE (350 mg/ml of nonionic contrast agent,
80-100 ml) and repeat scan after 10,
20 and 120 sec,
especially in suspicious cases (epidural and soft tissue abscesses) directly after viewing of native images.
Accumulation of the CE in puss collections walls of soft tissue and epidural masses most pronounced and it visualized clearly in venous and delayed phases (Fig.5).
Performing CT after MRI was used when radiologist need to identified any changes in lungs and mediastinum,
for planning the upcoming surgery (especially to determine the length and position of transpedicular screws and bone density).
The advantage of CT was the ability to visualize even small areas of bone destruction.
All patient were examined by 1.5 T MRI with SG T1,
T2,
STIR; COR T2,
AX T1,
T2 sequences.
In 27 cases we additional used AX T2 3-4 mm slice thick through all interest zone («wide scan» - usually include one or two IVD and nearby proximal and distal VB or IVD and intact VB).
For 18 patients we made 3 mm T2 scans through IVD (patient after small injury volume; nearby IVD with other changes like prolapses,
isolated discitis) (Fig.6).
DWI AX was used in 3 patients,
MR-myelography - 4 times.
We did more than one «widescan» in patients with injury in L-spine and sacrum in the same time (due to the difference in the scanning plane).
AX «wide scan» allows to clearly define the area and length of the spinal canal stenosis (Fig.7).
MRI performed with CE to 20 patients: we duplicate non-contrast T1SG and AX 3-4 mm with same parameters as pre-contrast scans through a zone of interest (at 4 of 20 patients include fat suppression sequences).
Scanning was performed immediately after CE.
We used 0,5 (0,2 ml/kg) and 1,0 (0,1 ml/kg) mmol/ml contrast agent.
CE was useful to detect clearly borders of puss collections (Fig.8) and promote to detect small epiduritis (Fig.
9),
myelitis,
reactive thickening of lig.
longitudinale posterior.
For all patient with back pain it’s necessary to use analgesia before MRI to prevent moving artifacts.
We repeat MRI in 35% (max.
4 times) of patients on hospital stage and notice,
that changes in VB,
IVD (edema,
infiltration) and epidural spaces regress slowly with conservative treatment.
That’s why repetition of MRI study often than through 3-4 weeks is not useful.
By contrast,
study after surgical treatment when dinamics usually is more pronounced.