"10.3109/02688697.2013.872229" . . . "The recognition of anaplastic foci within low-grade gliomas is of extreme importance in patients under follow-up for Grade II gliomas. We present the algorithm of MR spectroscopy (MRS)-guided brain biopsy and its correlation with tumour histology. Methods. Twenty-seven patients harbouring suspected Grade II/III glioma were examined on our 3T MR. 2D PRESS-CSI metabolite images of Choline/Creatine, Creatine/N-acetylaspartate and Choline/N-acetylaspartate were calculated and exported to the DICOM format. According to these maps, a stereobiopsy was performed at the point of maximum Choline/Creatine ratio prior to tumour resection. In the case of enhancing tumour, a subsequent biopsy was performed from the point of enhancement. Comparisons were made between the histology of the biopsied specimens and the resected tumours. Results. Eleven tumours were diagnosed as high-grade and sixteen as low-grade lesions. The correlation between main spectroscopic ratios (Cho/Cr and Cho/NAA) was strongly positive at the points of maximum Cho/Cr. Similar results were obtained at the points of contrast enhancement. Comparison of histological parameters of biopsy samples at the points of maximum Cho/Cr and histological examination of the completely resected tumours gives a strong correlation of tumour grade, number of mitoses and Ki-67 expression. The diagnostic accuracy of MRS-guided biopsy was 84%. The absolute value of Cho/NAA was higher in high-grade compared to that of low-grade lesions. The value of Cho/NAA ratio of 0.9 using MRS produced a sensitivity and specificity of 78% in the differentiation between low-grade and high-grade lesions. Combining MRS with structural MR, the sensitivity increased to 86% and the specificity to 80%. Conclusions. Strong correlation was demonstrated between Cho/Cr and Ch/NAA ratios. ches"@en . . "GB - Spojen\u00E9 kr\u00E1lovstv\u00ED Velk\u00E9 Brit\u00E1nie a Severn\u00EDho Irska" . "Bene\u0161, Vladim\u00EDr" . . . . . . "5" . . "Recognition of anaplastic foci within low-grade gliomas using MR spectroscopy" . "000341753500010" . . . "RIV/00216208:11110/14:10285576!RIV15-MSM-11110___" . "de Lacy, Patricia" . . "Netuka, David" . "stereotactic biopsy; MR spectroscopy; MR imaging; low-grade glioma; brain tumour; anaplastic focus"@en . "The recognition of anaplastic foci within low-grade gliomas is of extreme importance in patients under follow-up for Grade II gliomas. We present the algorithm of MR spectroscopy (MRS)-guided brain biopsy and its correlation with tumour histology. Methods. Twenty-seven patients harbouring suspected Grade II/III glioma were examined on our 3T MR. 2D PRESS-CSI metabolite images of Choline/Creatine, Creatine/N-acetylaspartate and Choline/N-acetylaspartate were calculated and exported to the DICOM format. According to these maps, a stereobiopsy was performed at the point of maximum Choline/Creatine ratio prior to tumour resection. In the case of enhancing tumour, a subsequent biopsy was performed from the point of enhancement. Comparisons were made between the histology of the biopsied specimens and the resected tumours. Results. Eleven tumours were diagnosed as high-grade and sixteen as low-grade lesions. The correlation between main spectroscopic ratios (Cho/Cr and Cho/NAA) was strongly positive at the points of maximum Cho/Cr. Similar results were obtained at the points of contrast enhancement. Comparison of histological parameters of biopsy samples at the points of maximum Cho/Cr and histological examination of the completely resected tumours gives a strong correlation of tumour grade, number of mitoses and Ki-67 expression. The diagnostic accuracy of MRS-guided biopsy was 84%. The absolute value of Cho/NAA was higher in high-grade compared to that of low-grade lesions. The value of Cho/NAA ratio of 0.9 using MRS produced a sensitivity and specificity of 78% in the differentiation between low-grade and high-grade lesions. Combining MRS with structural MR, the sensitivity increased to 86% and the specificity to 80%. Conclusions. Strong correlation was demonstrated between Cho/Cr and Ch/NAA ratios. ches" . "[F5A7D1C8843F]" . . "http://dx.doi.org/10.3109/02688697.2013.872229" . "Vr\u00E1na, Ji\u0159\u00ED" . "28" . . . "9"^^ . . "0268-8697" . "41600" . "11110" . "5"^^ . "P(GPP304/10/P464), V" . . "Recognition of anaplastic foci within low-grade gliomas using MR spectroscopy" . . "6"^^ . "British Journal of Neurosurgery" . . "Hrabal, Petr" . . "Kram\u00E1\u0159, Filip" . . "Recognition of anaplastic foci within low-grade gliomas using MR spectroscopy"@en . . "RIV/00216208:11110/14:10285576" . "Recognition of anaplastic foci within low-grade gliomas using MR spectroscopy"@en . . "Brad\u00E1\u010D, Ond\u0159ej" . "J\u00EDr\u016F, Filip" . "Ho\u0159\u00EDnek, Daniel" .