Lateral aperture

The lateral aperture of the fourth ventricle or foramen of Luschka (after anatomist Hubert von Luschka) is an opening at the lateral extremity of either lateral recess of the fourth ventricle opening anteriorly  into (sources differ) the pontine cistern /lateral cerebellomedullary cistern at cerebellopontine angle. A tuft of choroid plexus commonly extends into the lateral aperture, partially obstructing CSF flow through this aperture.

The opening of the lateral aperture occurs just lateral to the cranial nerve VIII,  and proximally to the flocculus of cerebellum.