Figure 8-1 shows the current noise in series with the inverting input - since that is a current source, it is high impedance and would open the loop.
Normally, this is modelled as a current noise to ground at the V- node, not in series,
Also, this equation looks wrong, is this not a differential amplifer - this is close to the single ended transimpedance noise equation - except the /2 is a mystery element.
Also, the currents in this figure are incorrect, they do not flow out from both sides but through the diode in one direction,