Junction scotoma and involvement of the optochiasmal junction

In two patients, ipsilateral central scotoma and contralateral superior temporal hemianopic field defect indicated involvement of the junction of the optic nerve and chiasm, the optochiasmal junction. In both cases, computed tomography and carotid angiography confirmed mass lesions at this location. After surgical removal of a parasellar tumor in one case, we found that the optic nerve and the anterior part of the optic chiasm were compressed upwards. The previously reported examples of these perimetric findings are reviewed and compared with those of our cases. We concluded through this study that the characteristic combination of visual field defects, namely central or paracentral scotoma on the involved side and superior temporal field defect on the uninvolved side, should be termed junction scotoma.