Non-invasive stress imaging methods of diagnosing peripheral arterial disease via dynamic pet
The present invention provides a method of determining whether a subject is suffering or at a risk of developing a peripheral arterial disease via Positron Emitting Tomography (PET) imaging technology. The method comprises administering a PET radionuclide into the subject via automated generation and/or infusion system, performing PET scan of the region of interest, automated assessment of the PET images, performing assessment and suggesting the most appropriate therapeutic and/or management options for the patients based on the severity score, provides an assessment of regional lower proximity perfusion and perfusion reserve, and/or regional and mean standardized uptake values (SUVs). More particularly, the method of image processing identifies the regional differences in SMP (Skeletal muscle perfusion) and SMPR (Skeletal muscle perfusion reserve) across calf muscles at rest and cuff-induced hyperemia.
1 . A method of diagnosing and/or treating a peripheral artery disease in a subject suffering from metabolic disease comprising:
a) calculating a dose of Rb-82 chloride to be administered to the subject;
b) administering the calculated dose of Rb-82 chloride to the subject by an automated generation and infusion system and scanning a region of interest;
c) administering a pharmacologic stress agent and second dose protocol after resting dose infusion and scanning the region of interest;
d) performing an assessment of images using continuous bed motion shuttle mode; and
e) diagnosing peripheral arterial disease in the subject thereof;
wherein the continuous bed motion shuttle mode is performing:
i) a single bed positron emission tomography acquisition of the heart for about 1-10 minutes;
ii) a single bed positron emission tomography acquisition of the leg for about 1-10 minutes;
iii) a single bed centered positron emission tomography acquisition at abdominal aorta of the subject for about 1-3 minutes;
iv) continuous bed motion positron emission tomography scan of the subject between abdominal aorta and legs;
v) calculating an input function from abdominal artery based on one or more parameters selected from abdominal artery diameter and scanner resolution; and
vi) calculating the tracer flux (K1) into the tissue or region of interest;
wherein the tracer flux (K1) is less than 0.05 ml/min/cm 3 in occluded tissue in comparison to non-occluded tissue and is associated with peripheral arterial disease.
2 . The method according to claim 1 , wherein the metabolic disease is diabetes mellitus.
3 . The method according to claim 1 , wherein automated generation and infusion system comprises Rb-82 generation and infusion system.
4 . The method according to claim 1 , wherein the dose of Rb-82 ranges from 0.01 mBq to 10,000 mBq.
5 . The method according to claim 1 , wherein the assessment of images using continuous bed motion shuttle mode comprises positron emission tomography imaging.
6 . The method according to claim 1 , wherein the region of interest comprises area between abdominal aorta to lower extremities.
7 . The method according to claim 1 , wherein the region of interest comprises lower extremities or limbs of the subject.
8 . The method according to claim 1 , wherein the scanning technique comprises multi-pass continuous bed motion between abdominal aorta and lower extremities.
9 . The method according to claim 1 , wherein the diagnosis comprises determining the presence or absence of the peripheral arterial disease in the subject.
10 . The method according to claim 1 , wherein the diagnosis comprises identifying the subject at a risk of developing the peripheral arterial disease.
11 . The method according to claim 1 , wherein the protocol further comprises performing a computed tomography and/or magnetic resonance imaging of the subject.
12 . The method according to claim 1 , further comprising:
a) calculating a dose of Rb-82;
b) administering the calculated dose of Rb-82 in the subject at rest and stress condition;
c) image capturing by PET scanner using continuous bed motion shuttle mode;
d) performing quantitative assessment of blood flow in lower extremities or limbs of the subject;
e) performing image analysis and providing a severity score based on the assessment;
f) performing diagnosis or identify the subjects at risk of developing peripheral arterial disease; and
g) generating a report.
13 . The method according to claim 1 , wherein the calculated dose of Rb-82 uptake potential or blood flow or perfusion threshold value is calculated as K1, which is based on blood perfusion as volume per unit time per unit volume of the tissue.
14 . The method according to claim 13 , wherein the threshold value is calculated in comparison to the occluded tissues to normal tissues or unoccluded tissues.
15 . The method according to claim 14 , wherein the threshold value can range from 0.01 to 1.5.
16 . The method according to claim 1 , further comprising validating the tracer flux (K1), wherein the tracer flux (K1) is validated by injecting microspheres over 30 seconds during the positron emission tomography imaging at rest or stress conditions and blood flow is measured in gastrocnemius and soleus muscles.