Chronic Visual Abnormality in an Elderly Patient With Temporal Lobe Epilepsy

Abstract

A 79-year-old woman visited our department for chronic visual field abnormalities with a floating sensation for two months. Neurological and ophthalmologic examinations yielded normal results, except for brain MRI indicating left hippocampal atrophy. Cognitive function tests were normal. EEG revealed frequent spikes and slow waves in the left frontotemporal region, corroborated by reduced accumulation in ¹²³I-iomazenil single photon emission computed tomography. A diagnosis of temporal lobe epilepsy was established, and treatment with lacosamide resulted in a remarkable improvement in symptoms and EEG findings. Mild focal seizures from the temporal region might cause mild impaired awareness, resulting in the patient's report as a sensation of uncertainty between the self and the outside world, mimicking ophthalmologic abnormalities. The repeated nature of the seizures contributed to the absence of the term "transient" in symptom description. Diagnosing epilepsy in the elderly proves challenging due to nonspecific complaints.

Keywords: clinical neurophysiology; elderly; electroencephalography; focal seizure; loss of awareness.

Figure 1. Brain imaging and interictal EEG

A. Brain MRI with FLAIR imaging demonstrates atrophy of the medial temporal lobe on the left; B. 123I-iomazenil SPECT (B1: early and B2: late phase) reveals findings compatible with left temporal lobe epilepsy; C. Interictal EEG displays bilateral independent focal sharp waves, predominantly on the left. FLAIR: fluid-attenuated inversion recovery