Establishing a reference range for oligodendroglioma classification using Higuchi Dimension analysis

Gliomas are the most common type of brain tumours in adults and a significant cause of cancer-related mortality. The 1p/19q chromosome deleted oligodendroglioma subtype has been shown to have a good prognosis following chemotherapy. However the subjectivity inherent with associated tissue features in classifying this tumour has led to some uncertainty in diagnosis and identifying optimal treatment options. This study investigated the use of the Higuchi dimension (DH) as a diagnostic tool to differentiate between the oligodendrogliomas with and without loss of heterozygosity (LOH & noLOH respectively). Sixty-five neurosurgical resection specimens were analysed. DH was lower in the LOH tissue (mean±sd; 1.69±0.01; CI:1.69-1.71; p<0.05) compared to the non-deletion group (1.83±0.04; CI: 1.81-1.85; p<0.05). Our results indicate that oligodendroglioma tissue showed scale invariance and that the complexity of the tissue as determined by the Higuchi dimension decreased with loss of genetic heterozygosity. Determination of the fractal dimension of gliomas provides an inexpensive and accurate alternative for classification of oligodendrogliomas.