Purpose
BACKGROUND
Advantages of abdominal CT perfusion (CTP) are
minimally invasive technique
high ability for quantification
wide distribution of CT scanner
low cost
Abdominal CTP has been suggested to be useful in
detection of hepatic micrometastasis
characterization of tumor
assessment of liver function
assessment of perfusion anomalies such as arterio-portal shunt (e.g.
TIPS) or congestion (e.g.
BCS,
transplant)
assessment of therapeutic effects
Problems still exist in
Limited cranio-caudal scan range
Long breathholding for portal flow measurement
Separation of arterial and portal blood flow
Standardization of analytic...
Methods and Materials
Patients
98 patients who were suspected to have hepatic metastasis,
underwent whole upper abdominal CTP examination.
Written informed consent obtained in all pts.
This study was limited to assessment of normal subjects proved by at least 6-months follow-up period,
because hemodynamics in patients with tumors or chronic diseases are quite different.
Therefore,
3 pts with hepatic metastasis,
2 with hepatic hemangioma,
1 with cirrhosis,
and 2 with chronic hepatitis were excluded.
Finally,
90 pts (m:57,
f: 33,
mean: 69.1 yrs) were included in this study....
Results
RESULTS
Hepatic Perfusion Parameters
These parameters showed no particular trend dual-input MS and DC methods (Fig.
2).
There was a significant difference in arterial perfusion fraction indual-input CM method(Fig.
3).
Splenic,Pancreatic,
and GastricPerfusion Parameters
These parameters showed no particular trend in 3 single-input methods (Fig.
4-6).
SUMMARY
A significant difference was only found in compartment model method in the liver.
DISCUSSION
When using MS or DC methods,
abdominal CT perfusion can be performed with flexible CM injection protocols.
Previous Reports on Inj.
Protocol for CTP...
Conclusion
Perfusion values of the upper abdominal organs are not affected by CM concentration except for dual-input compartment analysis in the liver.
When using maximum slope or deconvolution methods,
abdominal CT perfusion can be performed with flexible CM injection protocols.
References
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