Can SV lenses be upside down?

I was wondering if SV lenses have to be oriented in a certain way, or
if they can be upside down.

Since I am very myopic, I can see the little symbols (micro
engravings) on my new pair of glasses. I have drawn them in this
diagram (jpg):
http://members.shaw.ca/helfrich/glasses.jpg

The diagram is head-on, as if you are looking at me. The lenses are
Essilor SV 360 "digital". As you can see, the left lens (right lens in
the diagram) is upside down. My question is, with single-vision
lenses, does the orientation of the lens matter? Do the circles have
to be 180 degrees (they are slightly angled), and the lens right-side-
up? Or is the lens intentionally upside down because of my
astigmatism?

My old glasses prescription was:

R: -12.00 -0.75 066
L: -12.50 -1.00 172

My new glasses prescription is:

R: -11.75 -1.00 072
L: -13.75 -025 169

PD is 63 for both sets of glasses.

I have had these glasses for three days, and so far, have not adjusted
to them (my vision, both near and far, is better with my old glasses).

Thanks very much.