These dense regions should affect the temperature of the microwave background. So observers worked for years to get enough sensitivity to see the temperature differences around the sky. The map above is from COBE and is much better than Conklin's 2 standard deviation detection. This is how we measure the velocity of the Solar System relative to the observable Universe. The anisotropy in this map has an RMS value of 30 microK, and if it is converted into a gravitational potential using Sachs and Wolfe's result and that potential is then expressed as a height assuming a constant acceleration of gravity equal to the gravity on the Earth, we get a height of twice the distance from the Earth to the Sun.
Inflation predicts a certain statistical pattern in the anisotropy.
The quantum fluctuations normally effect very small regions of space, but the huge exponential expansion during the inflationary epoch makes these tiny regions observable. The space-time diagram on the left above shows the future lightcones of quantum fluctuation events. The top of this diagram is really a volume which intersects our past lightcone making the sky. The future lightcones of events become circles on the sky. Events early in the inflationary epoch make large circles on the sky, as shown in the bottom map on the right.