Visual field defects after temporal lobectomy -- comparing methods and analysing resection size.

OBJECTIVES

The frequency of visual field defects (VFD) after temporal lobe resections (TLR) was compared for two types of TLR and VFD frequency was correlated to resection size.

METHODS

Pre- and post-operative perimetry results were analysed for 50 patients with TLR for medically intractable epilepsy. Thirty-three patients had a classical TLR and 17 had a TLR with less lateral extension. Post-operative MRIs were studied in 34 patients by scoring resection size in 12 compartments in the temporal lobe.

RESULTS

Twenty-five patients developed a VFD. In the classical TLR group, 16 of 33 developed a VFD, compared with nine of 17 in the other group. The resection points were higher for the VFD group in the most anterior compartment studied, in the superior temporal gyrus.

CONCLUSIONS

There was no clearcut difference in VFD frequency between the surgical methods studied. However, the compartmentalized analysis disclosed a relation between the extent of resection in the anterior part of the superior temporal gyrus and VFD frequency.