Abstract: An endovascular apparatus can comprise an array of emitters configured to emit light at a predetermined wavelength and an array of sensors configured to detect light emitted by the emitters and reflected off a surface. The device can be configured to be inserted into a stent within a blood vessel of a patient and the device can be configured to detect the location of a branch blood vessel based on the reflected light detected by the array of sensors. Some devices detect light through a stent wall from an emitter positioned in the branch vessel. Some devices include fiber optics or phototransistors for receiving light from the emitter. Some devices include a fenestration former and a guidewire director along with the light receivers all in one endovascular device.