Malignant focal brain lesions. Value of MRS tumour biomarkers in preoperative prediction of grades of malignancy

Purpose

Our aim is to describe the spectrum of proton-MR spectroscopy in malignant focal brain lesions and to detect grade of malignancy using MRS tumor biomarkers.

Materials and methods

87 patients (63 males and 24 females) with focal brain lesion(s) are included in this study. All had a brain tumor recently diagnosed by MRI and had received no previous treatment. They were referred to MRS examination before surgical biopsy and/or resection or radiotherapy.

Results

In malignant brain tumors, average Cho/NAA ratio was 3.3 ± 0.22, Cho/Cr ratio was 2.95 ± 0.21, MI/NAA ratio was 1.5 ± 0.12, MI/Cr was 0.53 ± 0.11 with lower MI levels and higher choline levels in more malignant tumours, lipid/lactate peak was detected in brain metastasis and high grade malignant brain tumors.

Conclusion

Higher Cho/NAA, Cho/Cr and MI/NAA ratios with lower MI/Cr, and high lipid/lactate peak, were most likely to be in high grade malignant brain tumors.     

Evaluation of metabolic changes within the normal appearing gray and white matters in neurologically asymptomatic HIV-1-positive and HCV-positive patients: Magnetic resonance spectroscopy and immunologic correlation

Objective

The aim of the study was to evaluate early metabolic changes using proton MR spectroscopy (MRS) in asymptomatic HIV-1-positive and HCV-positive patients without abnormalities in the structural MR examination.

Methods

Sixty-five asymptomatic patients: 21 HIV-1-positive naive, 20 HIV-1-positive with combination antiretroviral therapy (cART), 9 HIV-1/HCV-positive naive, 15 HCV-positive naive and 18 normal subjects were enrolled in the study. The MRS examinations were performed with a 1.5 T MR scanner. Voxels were located in the following regions: posterior cingulate gyrus (PCG), anterior cingulate gyrus (ACG), parietal white matter (PWM), left basal ganglia (BG) and frontal white matter (FWM). The NAA/Cr, Cho/Cr, mI/Cr ratios and correlations of MRS measurements with the immunologic data were analyzed.

Results

There was a significant decrease (p < 0.05) of the NAA/Cr ratios in PCG, ACG and PWM regions in HIV-1-positive cART treated patients compared to the normal subjects. The significantly decreased NAA/Cr ratios in PWM and FWM were observed in HCV infected patients. The subjects with HIV-1/HCV co-infection revealed significantly lower NAA/Cr ratios in the ACG area. Other metabolite ratios in all analyzed regions, as well as the NAA/Cr ratios in BG showed no significant differences. The decrease of CD4n T cell count was associated with the decease of the NAA/Cr ratio in the PCG area and the increase of Cho/Cr ratio in the FWM region.

Conclusions

The metabolic changes – reduction of NAA/Cr ratios are most pronounced in HIV-1-positive patients using cART. The low CD4n T cell count is a risk factor for neurocognitive impairment in HIV-1-positive patients.     

Differentiation of intracranial tuberculomas and high grade gliomas using proton MR spectroscopy and diffusion MR imaging

Objective

The purpose of this study was to determine whether proton MR spectroscopy (¹H MRS) and diffusion-weighted (DW) imaging can be used to differentiate intracranial tuberculomas from high grade gliomas (HGGs).

Materials and methods

A total of 41 patients (19 with intracranial tuberculomas and 22 with HGGs) were examined in our study. ¹H MRS and DW imaging were performed at a 1.5T MR scanner before operation or treatment. Concentrations of N-acetylaspartate (NAA), creatine (Cr), choline (Cho), and lipid and lactate (LL) in the contrast-enhancing rim of each lesion were expressed as metabolite ratios and were normalized to the contralateral hemisphere. The apparent diffusion coefficient (ADC) was also calculated. The metabolite ratios and ADC values in the enhancing rim of intracranial tuberculomas and HGGs were compared using the Wilcoxon rank sum test. Diagnostic accuracy was compared using receiver operating characteristic (ROC) analysis.

Results

Significant differences were found in the maximum Cho/Cr (P = 0.015), Cho/NAA (P = 0.001) and Cho/Cho-n ratios (P = 0.002), and minimum ADC value (P < 0.001) between the intracranial tuberculomas and HGGs. Diagnostic accuracy was higher by minimum ADC value than maximum Cho/Cr, Cho/NAA and Cho/Cho-n ratios (93.8% versus 75.7%, 80.8% and 78.1%).

Conclusion

These results suggest a promising role for ¹H MRS and DW imaging in the differentiation between the intracranial tuberculomas and HGGs.     

Interictal alterations of thalamic metabolic concentration ratios in migraine without aura detected by proton magnetic resonance spectroscopy

Aim of the work

To detect interictal changes of the metabolic concentration ratios in the thalami of patients with migraine without aura by using 1H-MRS.

Materials and methods

Twenty-two patients of migraine without aura were enrolled in this study in addition to 10 healthy controls. Patients were further divided into 2 subgroups; 12 with left-sided migraine and 10 with right-sided migraine. Patients were imaged interictally with multivoxel 1H-MRS for measuring the NAA/Cho, NAA/Cr, Cho/Cr, MI/NAA and Lac/NAA ratios in both thalami.

Results

Each of the mean NAA/Cho and NAA/Cr ratios was significantly decreased in patients compared to controls, and also on the contralateral side compared to the side of migraine in each subgroup of patients. In contrary, no significant difference was found in Cho/Cr, MI/NAA and Lac/NAA ratios between patients and controls, as well as on comparing both sides in each subgroup of patients. Furthermore, increased duration of illness and frequency of attacks were significantly associated with decreased NAA/Cho and NAA/Cr ratios as well as increased MI/NAA and Lac/NAA ratios.

Conclusion

Migraine without aura is associated with thalamic interictal changes in the mean metabolite concentration ratios, detected with multivoxel 1H-MRS.     

Predicting grade of cerebral gliomas using Myo-inositol/Creatine ratio

Purpose

Our aim was to determine the diagnostic accuracy of MI/Cr ratio in determining the grade of glioma.

Materials and methods

Twenty-two patients (14 males and 8 females), ranging in age from 15–63 years (mean 34.4 years) were prospectively recruited for this study. All had a brain tumor recently diagnosed by MRI and had received no previous treatment, except for steroids. They were referred for MRS examination before surgical biopsy and/or resection or radiotherapy. Ratios for MI/Cr, Cho/Cr, and Cho/NAA were obtained for each lesion and compared with the grade of the lesion.

Results

The levels of MI/Cr were higher (2.14 ± 1.4) in patients with low-grade astrocytoma, and lower in patients with anaplastic astrocytoma (0.39 ± 0.11) and GBM (0.025 ± 0.06). 21 out of the 22 patients were correctly classified using MI/Cr ratio, one patient was misdiagnosed as high grade glioma and the biopsy revealed grade II glioma. The diagnostic accuracy, sensitivity and specificity of MI/Cr ratio for the grading of glioma was 95.4%, 100%, and 92.8%, respectively.

Conclusion

MRS has proven to be an important complementary tool saving the patient from unnecessary biopsy taking when it is conclusive thus altering the treatment planning. This study had demonstrated that MI level and MI/Cr ratio are important in presurgical grading of brain tumors.     

An experimental study on acute brain radiation injury: Dynamic changes in proton magnetic resonance spectroscopy and the correlation with histopathology

Purpose

To investigate the correlation between the alterations of single-voxel ¹H MRS and the histopathological characteristics of radiation brain injury following radiation.

Materials and methods

Twenty-seven rabbits were randomized into nine groups to receive radiation with a single dose of 25 Gy. The observation time points included a pre-radiation and 1, 2, 3, 4, 5, 6, 7, and 8 wk following radiation. Each treatment group underwent conventional MRI and single-voxel ¹H MRS, N-acetyl aspartate (NAA), choline (Cho), and creatine (Cr) were observed over the region of interest, and the presence or absence of lactate (Lac) and lipid (Lip) was detected. Histological specimens of each group were obtained after image acquisition.

Results

The values of Cho were significantly increased in the first 3 wk, and decreased over the following 5 wk after radiation. Levels of NAA showed a trend toward a decrease 5 wk after radiation. The levels of Cr were not changed between before and after radiation. The Cho/NAA metabolic ratio was significantly increased in weeks 6, 7, and 8 following irradiation, compared to pre-radiation values. Vascular and glial injury appeared on 2 wk after RT in the histology samples, until 4 wk after RT, necrosis of the oligodendrocytes, neuronal degeneration and demyelination could be observed.

Conclusions

MRS is sensitive to detect metabolic changes following radiation, and can be used in the early diagnosis of radiation brain injury.     

MRS of brain tumors: Diagrammatic representations and diagnostic approach

Purpose

To evaluate magnetic resonance spectroscopy (MRS) in the assessment of brain tumors and grading brain glioma.

Patients and methods

Retrospective study was done for 42 patients with diagrammatic representations suggested by the author for the assessment of MRS data.

Results

Pathology grading was correlated with metabolic ratios in cases of brain glioma. Ratios higher than 1.5 for either Cho/Cr or Cho/NAA were consistent with tumors and ratios higher than 2 were consistent with high grade glioma or metastases.

Conclusion

MRS can be used to grade cases of brain glioma. Diagrammatic representations and a diagnostic approach were suggested by the author to simplify clinical practice.     

In vivo neurobiochemical changes of the posterior cingulate gyrus in patients with Alzheimer’s disease detected by multivoxel proton magnetic resonance spectroscopy

Aim of the work

To study the neurobiochemical changes in patients with Alzheimer’s disease (AD) by multivoxel 1H-MRS.

Materials and methods

Twenty-five patients with probable AD and 12 age- and sex-matched normal controls were subjected to assessment of cognitive functions by the Mini Mental State Examination (MMSE) and imaging with multivoxel 1H-MRS for measuring the NAA/Cho, NAA/Cr, Cho/Cr, MI/NAA and MI/Cr ratios in the posterior cingulate gyrus (PCG) bilaterally.

Results

Patients with AD showed significant decrease in NAA/Cho and NAA/Cr, significant increase in MI/NAA and MI/Cr and non-significant increase in Cho/Cr ratios compared to control. Also, the severity of cognitive impairment was significantly associated with these changes. The NAA/Cho ratio at a cut-off value ?1.14 showed accuracy (94%), the NAA/Cr ratio at a cut-off value ?1.40 showed accuracy (97%), the Cho/Cr ratio at a cut-off value >1.29 showed accuracy (85%), the MI/NAA ratio at a cut-off value >0.60 showed accuracy (98%), and the MI/Cr ratio at a cut-off value >0.83 showed accuracy (97%).

Conclusion

The multi-voxels 1H-MRS of the PCG is sensitive to biochemical changes in AD. The 1H-MRS peak metabolite concentration ratios may be useful as markers for the progression of AD.     

Magnetic resonance spectroscopy in patients with Fabry and Gaucher disease

Objective

Fabry and Gaucher diseases are rare progressive inherited disorders of glycosphingolipid metabolism that affect multiple organ systems. The aim of this study was to investigate evidence for metabolic changes in the central nervous system involvement using proton magnetic resonance spectroscopic imaging.

Methods

Seven Fabry and eight Gaucher patients were included into this study. A two-dimensional, spectroscopic imaging method with an ultra-short echo-time of 11 ms was used at a 3 T whole body magnet. Absolute metabolic values were retrieved using internal water scaling. Results were compared, with sex- and age-matched controls.

Results

In contrast to previous findings, absolute and relative metabolite values of N-acetyl-aspartate (NAA) or NAA/Creatine (Cr), Cr, Choline (Cho) or Cho/Cr and myo-Inositol (mI) or mI/Cr revealed no, differences between Fabry and Gaucher Type 1 (GD1) patients and controls. Average values were, 10.22, 6.32, 2.15 and 5.39 mMol/kg wet weight for NAA, Cr, Cho and mI, respectively. In this study, we found significantly decreasing NAA/Cho with increasing age in all three groups (Fabry, GD1, patients and healthy controls) (between 5 and 8% per decade).

Conclusions

There were no changes of the quantified metabolites detected by MRS in normal appearing white matter. This study shows the importance of sex- and age-matched controls.     

Role of magnetic resonance spectroscopy in differentiation between recurrence of glioma and post radiation injury

Purpose

This study aims to evaluate the role of MR spectroscopy in the detection of recurrent glioma and differentiation from post radiation injury.

Patients and methods

32 patients (20 males and 12 females) complaining of different neurological symptoms were enrolled prospectively in this study between September 2011 and December 2013. These patients were selected on the basis that they were known patients with pathologically proved glioma who underwent radiotherapy. All patients underwent standard MRI examination and MR spectroscopy.

Results

This study included 32 patients, twenty four patients (75%) proved histologically to be of recurrent glioma (group I) and 8 cases (25%) diagnosed as post radiation injury (group II). Peri-tumoral infiltration was present in 18 cases (56.25%) of recurrent glioma. Significantly increased Cho/Cr and Cho/NAA ratios were observed in neoplastic (n = 24) compared with non-neoplastic lesions (n = 8). Presence of lactate and lipid yielded correct classification as neoplastic and non-neoplastic lesions.

Conclusion

Magnetic resonance spectroscopy is a useful tool for the detection of recurrent glioma and differentiation from post radiation injury.     

MR spectroscopy,S100B protein and NSE analysis as early predictors of hypoxic ishaemic encephalopathy

Aim of work

The aim of this work is to assess S100B protein, neuron specific enolase and magnetic resonance spectroscopy as biochemical and imaging findings in neonatal hypoxic ischemic encephalopathy.

Methods

This prospective study on 30 full-term neonates suffering from HIE who were attendants of the Neonatology Unit of Pediatric Department and Radiodiagnosis Department of Tanta University Hospital. Duration of the study extended from June 2010 to June 2012.

Results

Thirty patients (16 males and 14 females), HIE group classification according to Lac/Cr ratio in MRS to three groups: Groups – group I: where Lac/Cr < 0.5, group II: where Lac/Cr 0.5–1.5 and group III: where Lac/Cr > 1.5.¹HMRS group I contained 17 patients (15 patients were present in Sarnat stage I and two patients were present in Sarnat stage II). Group II contained nine patients (all patients were present in Sarnat stage II). Group III contained four patients (all patients were present in Sarnat stage III).Serum level of S100B protein and NSE were significantly higher in the HIE group than control group also serum level of S100B protein and NSE in HIE stage III was significantly higher than control, HIE stage I and stage II.

Conclusion

¹HMRS is a useful tool for evaluating the severity and prognosis of HIE noninvasively. Higher lactate/Cr ratio in basal ganglia and thalamus predict the poor prognosis of neonates.Serum level of S100B protein and NSE has an important meaning in adjuvant diagnosing and ruling out diagnosis of early HIE and prognosis of birth asphyxia.     

Role of diffusion MRI and proton magnetic resonance spectroscopy in characterization of ovarian neoplasms

Introduction

Adnexal masses are a common clinical problem and considered as the leading indication for gynecological surgery. The ovary and adnexal structures are relatively difficult to image with any technology. Magnetic resonance spectroscopy (MRS) can detect metabolic changes. As molecular changes often precede morphologic alterations, sensitivity is expected to improve by MRS. Diffusion weighted magnetic resonance imaging (DW-MRI) is sensitive to molecular diffusion which is due to random microscopic translational motion of molecules (known as Brownian motion). In the event of morphologic evaluation of cystic ovarian tumors, whether benign or malignant, DW-MR imaging and calculated apparent diffusion coefficient (ADC) values would be useful for evaluation.

Purpose

The aim of this study is to evaluate the role of diffusion MRI & proton magnetic resonance spectroscopy (H-MRS) in diagnosis of ovarian neoplasms.

Subjects and methods

This study included 20 patients, their ages ranged from 20 to 72 years. In all cases, diagnosis was proven by surgical and pathological examination. Trans-abdominal ultrasound (n = 20) and trans-vaginal ultrasound (n = 11) were included in our routine protocol to obtain baseline information preceding MR examination. The routine MR examination protocol included: T1WI, T2WI, and post contrast fat suppressed T1WI. Diffusion weighted imaging (DWI) was done to all patients at b0, b500, b1000 and ADC values were calculated. MRS was performed in all cases using multi-voxel point resolved surface coil spectroscopy (PRESS sequence) for volume localization.

Results

Fourteen cases (70%) had benign ovarian masses while the remaining six cases (30%) had malignant masses. High lipid peak was detected in all three cases of mature cystic teratoma. All cases of simple serous cysts showed choline and creatine signals that were higher than the average noise level but lower than the two fold higher noise level. Sharp choline peak was detected in all malignant ovarian masses (except a case of metastases under chemotherapy) as well as the case of fibroma. Creatine signal was detected in all benign and malignant masses except two cases of mature cystic teratoma and cases of endometrioma. Lactate signal was detected only in cases of hemorrhagic cysts, mature cyst teratoma and one case of endometrioma and not obtained in any of malignant lesions except dysgerminoma. High NAA signal was detected in dysgerminoma and all three cases of mature cystic teratomas. The mean Cho/Cr ratio was significantly higher in malignant than benign ovarian masses (<0.05), there was no significant difference in mean and lowest ADC values between malignant and benign lesions.

Conclusion

Proton MRS using Cho/Cr ratio added useful information for the diagnosis of different ovarian neoplasms. Direct visual assessment of DWI of ovarian lesions is not useful in differentiating benign from malignant ovarian lesions; determining the threshold of the ADC for diagnosing cystic ovarian tumors is difficult because of their large variance. Further experience with a larger and more biologically variable range of tumors is recommended.     

Apparent diffusion coefficient and Magnetic resonance spectroscopy in grading of malignant brain neoplasms

Aim

This work aims to study the role of combined apparent diffusion coefficient (ADC) and Magnetic resonance spectroscopy (MRS) in grading malignant brain neoplasms.

Methods

A prospective study included 40 patients who were evaluated by standard contrast enhanced MRI, diffusion weighted imaging and multivoxel spectroscopy.

Results

Statistically significant difference was found between tumoral ADC values in low grade versus high grade tumors and metastasis and also between the peritumoral ADC values in metastasis versus low and high grade tumors. Statistically significant difference is noticed between tumoral Cho/Cr ratio values in low grade versus high grade tumors and metastasis, and also peritumoral Cho/Cr ratio values in low grade and metastasis versus high grade tumors. Statistically significant difference between tumoral Cho/NAA ratio in low grade versus high grade tumors and metastasis and lastly between peritumoral Cho/NAA ratio in low grade and metastasis versus high grade tumors was found. Lipid and lactate peaks were found frequently in high grade tumors and metastasis.

Conclusion

The combination of calculated ADC values and MR spectroscopy is useful in grading of malignant brain tumors and were more useful together than each on its own.     

Clinical use of H MR spectroscopy in assessment of relapsing remitting and secondary progressive multiple sclerosis

Background

Conventional MRI has a limited ability to provide specific information about axonal pathology in MS, recently, MRI spectroscopy used for assessment of the axonal loss even in normal appearing white matter.

Objective

To assess the axonal degeneration in plaques and normal appearing white matter in patients with relapsing remitting MS and secondary progressive MS, and correlate their clinical disability using expanded disability status scale (EDSS) score with H¹ MRS abnormalities.

Patients and methods

Thirty-two MS patients (20 RRMS, 12 SPMS) and 20 controls were subjected to thorough history taking, clinical examination with special attention to: age at first symptoms, disease duration and the EDSS score. MRS was performed in order to map N-acetylaspartate (NAA), choline (Cho) and creatine (Cr).

Results

In SPMS, the NAA/Cr ratio and absolute concentrations for NAA in MS plaques and NAWM were significantly reduced compared to RRMS and to controls, also, significant relation with this metabolite values and clinical disability using EDSS score.

Conclusion

In SPMS patients group there were significant reduction in the levels of NAA in both plaques and NAWM compared to RRMS and control groups, moreover significant correlation of NAA reduction in the plaques of both groups related to clinical disability and disease progression.     

Correlation study of 3T-MR-DTI measurements and clinical symptoms of cervical spondylotic myelopathy

Objective

To discuss the correlation between diffusion tensor imaging (DTI) measurements, diffusion tensor tractography and the clinical symptoms of cervical spondylotic myelopathy.

Methods

Based on the Japanese Orthopedics Association (JOA) score, 104 cervical spondylotic myelopathy cases were first divided into four groups: mild, moderate, severe and serious groups. According to lesion signal characteristics, all cases were again divided into three groups: A(N/N): normal signal in both T1WI and T2WI; B (N/H): normal signal in T1WI but high signal in T2WI; and C (L/H): low signal in T1WI and high signal in T2WI. The apparent diffusion coefficient (ADC), fractional anisotropy (FA), λ1, λ2, and λ3 were measured and diffusion tensor tractography was performed in the seriously compressed section of the spinal cord.

Results

The FA values were positively correlated with JOA scores (r = 0.883, P < 0.05), and significantly different among four JOA groups (P < 0.05). The ADC, λ2, and λ3 were significantly different among the moderate, severe and serious groups as well as among the A, B, and C groups (P < 0.05). Declining FA values were found associated with increasing fiber bundle damage.

Conclusions

The FA values and the change patterns of fiber bundle were more sensitive than T2WI for spinal cord lesion, and were positively correlated with clinical symptoms.     

Neurochemical-structural changes evaluation of brain in patients with obstructive sleep apnea syndrome

Purpose

To evaluate neurochemical and structural changes in the patients with newly diagnosed obstructive sleep apnea syndrome (OSAS) by MR spectroscopy (MRS), T2 relaxometry, and diffusion weighted imaging (DWI).

Material and methods

Following the acquisition of routine cranial MR, MRS, T2 relaxometry, and DWI images; spectroscopic metabolite ratios and DWI–T2 relaxometry findings of the thalami, hippocampi, frontal white matter (FWM) and frontal cortex of 24 OSAS patients and 9 controls were statistically compared. The relationship between two groups was evaluated with Mann–Whitney test.

Results

Spectroscopic measurements in the frontal cortex and frontal white matter of the OSAS patients revealed significantly lower NAA/Cr ratios than those of the control group (P = 0.004 and P = 0.006, respectively). The measurements in the frontal white matter of the OSAS patients exhibited significantly lower NAA/Cho ratios compared with those of the control group (P = 0.005). Thalamic Cho/Cr ratios of the patient group were significantly higher than those of the control group (P = 0.002). In terms of the ADC–T2 relaxometry values, there was no significant relationship between the patient and the control groups (P > 0.05).

Conclusion

MRS is a useful and non-invasive modality in showing neurochemical changes in various regions of the brain but our data does not show any change on diffusion weighting or T2 quantification in the OSAS group. DWI and T2 relaxometry appear to be not effective techniques to evaluate the brain structural changes of the patients with newly diagnosed OSAS.     

Diagnostic yield of combined magnetic resonance spectroscopy and diffusion weighted imaging in intracranial neoplasms

Purpose

Our intention was to evaluate the role of combined diffusion magnetic resonance imaging and spectroscopy in diagnosis and grading of brain tumors.

Materials and methods

Ninety-three included cases underwent magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS) of the brain lesion, stereotactic or open biopsies and histopathological examination. MRI protocol included DWI and calculated ADC values. Multivoxel MRS spectroscopic technique (MVS) was used and all MRS metabolic parameters were obtained.

Results

High grade tumors had significantly lower ADC values than low grade tumors (P < 0.001). ADC values were the lowest in lymphoma (0.54 × 10⁻³ mm²/s) and the highest in craniopharyngioma (1.9 × 10⁻³ mm²/s). MRS revealed a statistically significant difference in CHO/NAA and CHO/Cr ratios between low and high grade tumors with P < 0.01 and P < 0.001, respectively. The mI/Cr ratio and presence of lactate, lipid and taurine also aided in differentiation and grading of brain tumors. The overall MRI/MRS sensitivity and specificity were 91%, 90.5%, respectively.

Conclusion

MRS has a robust diagnostic accuracy in cases of well defined high or low grade brain neoplasms. ADC value had the ability to confirm and differentiate low from high grade tumors in many situations where there were diagnostic confusions with MRS due to borderline values.     

Magnetic resonance spectroscopy in recurrent breast masses following conservative surgery and radiation therapy

Purpose

The purpose of our study was to assess the value of functional magnetic resonance spectroscopy (1H MRS) in evaluating patients with recurrent cancer breast after breast conservative therapy (BCT) and radiation therapy by the presence of the choline-containing compounds (Cho) as a marker of malignancy.

Patients and methods

Twenty-six patients were included in the study all the patients were subjected to previous BCT and associated radiation therapy. All of them were suspected to have tumor recurrence by clinical examinations, periodic mammographic examination and or ultrasonography. All the patients were submitted to dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) followed by magnetic resonance spectroscopy (MRS) at 1.5 T MRI machine.

Results

Local recurrence was confirmed by histopathology in 19 patients, MRS detected 18 patients with sensitivity of 94.7%, false positive was seen in one patient in whom histopathology revealed inflammatory mastitis (specificity 85.7%). One patient was false negative diagnosed by histopathology as ductal carcinoma in situ (DCIS) with negative predictive value of 85.7% and overall accuracy of 92.3%.

Conclusion

In our study breast MRS using choline (Cho) integral was accurate in evaluating patients with recurrent breast masses after BCT and radiation therapy. It reaches a high level of diagnostic performance.     

Multimodal imaging in cerebral gliomas and its neuropathological correlation

Introduction

Concerning the preoperative clinical diagnostic work-up of glioma patients, tumor heterogeneity challenges the oncological therapy. The current study assesses the performance of a multimodal imaging approach to differentiate between areas in malignant gliomas and to investigate the extent to which such a combinatorial imaging approach might predict the underlying histology.

Methods

Prior to surgical resection, patients harboring intracranial gliomas underwent MRIs (MR-S, PWI) and ¹⁸F-FET-PETs. Intratumoral and peritumoral biopsy targets were defined, by MRI only, by FET-PET only, and by MRI and FET-PET combined, and biopsied prior to surgical resection and which then received separate histopathological examinations.

Results

In total, 38 tissue samples were acquired (seven glioblastomas, one anaplastic astrocytoma, one anaplastic oligoastrocytoma, one diffuse astrocytoma, and one oligoastrocytoma) and underwent histopathological analysis. The highest mean values of Mib1 and CD31 were found in the target point “T’ defined by MRI and FET-PET combined. A significant correlation between NAA/Cr and PET tracer uptake (−0.845, p < 0.05) as well as Cho/Cr ratio and cell density (0.742, p < 0.05) and NAA/Cr ratio and MIB-1 (−0761, p < 0.05) was disclosed for this target point, though not for target points defined by MRI and FET-PET alone.

Conclusion

Multimodal-imaging-guided stereotactic biopsy correlated more with histological malignancy indices, such as cell density and MIB-1 labeling, than targets that were based solely on the highest amino acid uptake or contrast enhancement on MRI. The results of our study indicate that a combined PET-MR multimodal imaging approach bears potential benefits in detecting glioma heterogeneity.