You missed the angle.
See that bit of flesh on the edge of the arm at the top border?
The flesh appeared as if the face of the patient was hugely wide,
like some gross deformation.
You need a better perspective,
the whole pic.
However,
a possible theory could be either another individual is kneeling lowly by the patient,
and it's his/her face edge as they watch the instruments;
or,
it's the patient's left hand moving in that area.