MR-monitored LITT as a palliative concept in patients with high grade gliomas: Preliminary clinical experience

The purpose of this study was to evaluate the clinical utility of laser‐induced thermotherapy (LITT) as a palliative treatment for patients with high‐grade gliomas. Four consenting patients with recurrent high grade III/IV gliomas near the primary language or motor areas were palliatively treated with LITT (2–5 W, 3–13 minutes; Neodym YAG Laser, Dornier, Friedrichshafen, Germany). Temperature monitoring was performed by T1‐weighted turbo‐fast low‐angle shot (FLASH) imaging at 1.5 T (Siemens Magnetom SP 4000, Siemens, Erlangen, Germany). MRI studies before LITT included contrast‐enhanced conventional scans and functional activation studies to localize the primary motor cortex or language areas using an echoplanar imaging (EPI) spin‐echo (SE) sequence. Follow‐up studies consisted of contrast‐enhanced conventional scans as well as diffusion studies (contrast‐enhanced Fourier‐acquired steady‐state technique and EPI‐SE) and perfusion studies (EPI‐SE with .2 mmol of gadolinium (Gd)/kg body weight) to differentiate posttherapeutic effects from residual or recurrent tumor growth. Local tumor control was achieved in areas with laser energy deposition with clinically stable conditions ⩾ 6 months. Conventional contrast‐enhanced scans demonstrated strong enhancement surrounding ablated tumor components, which showed a reduction in CBV/CBF. Perfusion studies were useful to discriminate granulomatous tissue enhancement from residual or recurrent tumor growth. Careful application of LITT may evolve as an alternative palliative concept for patients with end‐stage high‐grade cerebral gliomas reducing clinical symptoms from circumscribed areas of pathology.