Drug induced autoenucleation with resultant chiasmal damage

I read with interest the report of Tuwir et al¹ of a case of autoenucleation with chiasmal damage. They note the rarity of this dramatic self mutilating event, and state that there have been only two other reports of contralateral field defect from chiasmal injury in instances of autoenucleation.

There have, however, been a number of other reports of temporal field defect in the remaining eye following either self enucleation or traumatic enucleation by an assailant. The consequences are the same regardless of who removes the eye. One of the two reports Tuwir et al cite, Parmar et al,² was of a young man whose eye was digitally enucleated by an assailant.

In their 1984 review article on autoenucleation, Krauss et al³ reported a 29 year old woman who had enucleated her right globe causing a complete temporal hemianopia in her remaining eye. They also reviewed the medical literature and found 19 cases of bilateral self enucleation (or of self mutilation so severe as to require enucleation) and 31 cases of unilateral self enucleation. Of the 18 eyes where the length of the attached optic nerve was noted, six occurred at or near the chiasm. They also found seven cases of traumatic avulsion of one eye resulting in a temporal hemianopia in the remaining eye.

In 1996, Arkin et al⁴ reported a 25 year old man with a temporal defect in his right eye after his left eye was pulled out by an assailant. A magnetic resonance image confirmed damage to the chiasm. And in 2002, Dilly and Imes⁵ reported a 54 year old schizophrenic man who removed his blind left eye causing a complete temporal hemianopia in his remaining right eye. His MRI showed avulsion of the lateral portion of his chiasm.

It appears that even though acts of traumatic enucleation are rare, associated chiasmal injury is common.