[1H-MR Spectroscopy of brain tumors in the course of radiation therapy: Use of fast spectroscopic imaging and single-voxel spectroscopy for diagnosing recurrence].

Abstract

PURPOSE:

To improve differential diagnosis of residual or recurrent tumor vs. tissue necrosis in the course of radiation therapy of neurosurgically-treated brain tumors by application of fast (1)H-MR spectroscopic imaging in combination with single-voxel spectroscopy (SVS).

METHODS:

54 patients after with malignant brain tumor (44 cases of glioblastoma, 10 other high-grade gliomas) were examined post-surgically in a total of 140 proton MRS examinations in the course of radiotherapy and in follow-up controls. Fast SI acquisition was performed as single-slice or double-slice TSI sequence with 32 x 32 phase encodings within 11 or 15 minutes, respectively. SVS with TR/TE 2000/272 ms yielded relative metabolite ratios, and in 15 patients the time courses of the absolute concentrations of brain metabolites were also determined.

RESULTS:

In the group of 44 patients that could be tracked by MRS until therapy completion, TSI localized in 23 patients a persistent or newly arisen distinct choline accumulation indicating residual or recurrent tumor after radiation therapy. In all these cases MRS diagnosis was confirmed histologically or by short-term follow-up. However, in 6 of 15 patients showing a normal choline pattern in the TSI acquisition, tumor recurrence appeared within three months. SVS provided early recognition of recurrent tumor when detecting characteristic alterations of metabolite concentrations oin therapy follow-up.

CONCLUSION:

TSI and SVS represent complementary MRS techniques and are able to diagnose tumor recurrence early and unambiguously in cases where focal choline accumulation is detected.

• Authors: F Träber, W Block, S Flacke, R Lamerichs, H Schüller, H Urbach, E Keller, H H Schild
• Journal: RoFo : Fortschritte auf dem Gebiete der Rontgenstrahlen und der Nuklearmedizin (Rofo) Vol. 174 Issue 1 Pg. 33-42 (Jan 2002) ISSN: 1438-9029 [Print] Germany
• Vernacular Title: 1H-MR-Spektroskopie von Hirntumoren im Verlauf der Strahlentherapie: Anwendung von schneller spektroskopischer Bildgebung und Einzelvolumen-MRS in der Rezidivdiagnostik.
• PMID: 11793282 (Publication Type: English Abstract, Journal Article)

Chemical References

• Choline

Topics

• Adult
• Aged
• Brain (physiopathology, radiation effects, surgery)
• Brain Neoplasms (physiopathology, radiotherapy, surgery)
• Choline (metabolism)
• Combined Modality Therapy
• Cranial Irradiation
• Energy Metabolism (physiology, radiation effects)
• Female
• Follow-Up Studies
• Glioblastoma (physiopathology, radiotherapy, surgery)
• Glioma (physiopathology, radiotherapy, surgery)
• Humans
• Magnetic Resonance Imaging
• Magnetic Resonance Spectroscopy
• Male
• Middle Aged
• Neoplasm Recurrence, Local (diagnosis, physiopathology)
• Neoplasm, Residual (diagnosis, physiopathology)
• Radiotherapy, Adjuvant
• Sensitivity and Specificity
• Treatment Outcome