Accuracy of apparent diffusion coefficient values and magnetic resonance imaging in differentiating suprasellar germinomas from chiasmatic/hypothalamic gliomas

Objective The aim of this study was to differentiate suprasellar germinomas from chiasmatic/hypothalamic gliomas (CHGs) using apparent diffusion coefficient (ADC) values and magnetic resonance imaging (MRI) characteristics. Materials and methods A cross-sectional study was conducted on 11 patients with suprasellar germinomas and 11 patients with CHGs who underwent pretreatment MRI. The ADC values (minimum and average ADC values) of the tumors were measured and the MRI characteristics were evaluated. Results The average and minimum ADC values of suprasellar germinomas were significantly lower than those of CHGs ( p = 0.016 and 0.004 respectively). The selection of 941.15 × 10−6 mm2/s as a cutoff value of the minimum ADC value was used to differentiate suprasellar germinomas and CHGs; the best results were obtained with area under the curve of 0.889, sensitivity of 87.5%, specificity of 77.8% and accuracy of 82.4%. MRI characteristics suggested the diagnosis of suprasellar germinomas were T2W hypointensity and involvement of pituitary gland and/or stalk. MRI characteristics suggested the diagnosis of CHGs was higher degree of contrast enhancement and presence of macrocysts. Conclusion ADC values have a role in differentiating suprasellar germinomas and CHGs, especially when imaging findings on conventional MRI are inconclusive. Furthermore, some MRI features are in favor of differentiation between these tumor entities including tumor location, cyst pattern, T2W hypointensity, degree of contrast enhancement, stalk and pituitary gland involvement.

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Value of Minimum Apparent Diffusion Coefficient on Magnetic Resonance Imaging as a Biomarker for Predicting Progression of Disease Following Surgery and Radiotherapy in Glial Tumors from a Tertiary Care Center in Northern India

Journal of Neurosciences in Rural Practice ◽

10.4103/0976-3147.203823 ◽

2017 ◽

Vol 08 (02) ◽

pp. 185-193 ◽

Cited By ~ 2

Author(s):

Pramod Kumar Gupta ◽

Rishi Awasthi ◽

Shalini Singh ◽

Sanjay Behari ◽

K. J. Maria Das ◽

...

Keyword(s):

Magnetic Resonance Imaging ◽

Diffusion Coefficient ◽

Magnetic Resonance ◽

Apparent Diffusion Coefficient ◽

Progressive Disease ◽

Resonance Imaging ◽

Glial Tumors ◽

Apparent Diffusion ◽

Adc Values

ABSTRACT Purpose: Studies have shown that cellularity of glial tumors are inversely correlated to minimum apparent diffusion coefficient (ADC) values derived on diffusion-weighted imaging (DWI). The purpose of this prospective exploratory study was to evaluate whether temporal change in “minimum ADC” values during follow-up predict progressive disease in glial tumors post radiotherapy and surgery. Materials and Methods: Adult patients of glial tumors, subjected to surgery followed by Radiotherapy (RT), were included in the study. Serial conventional magnetic resonance imaging with DWI at the following time points – presurgery, pre-RT, post-RT imaging at 3, 7, and 15 months were done. For “minimum ADC” values, multiple regions of interest (ROI) were identified on ADC maps derived from DWI. A mean of 5 minimum ADC values was chosen as “minimum ADC” value. The correlation was drawn between histology and minimum ADC values and time trends were studied. Results: Fourteen patients were included in this study. Histologies were low-grade glioma (LGG) - 5, anaplastic oligodendroglioma (ODG) -5, and glioblastoma multiforme (GBM) - 4. Minimum ADC values were significantly higher in LGG and GBM than ODG. Presurgery, the values were 0.812, 0.633, and 0.787 × 10−3 mm2/s for LGG, ODG, and GBM, respectively. DWI done at the time of RT planning showed values of 0.786, 0.636, 0.869 × 10−3 mm2/s, respectively. During follow-up, the increasing trend of minimum ADC was observed in LGG (P = 0.02). All these patients were clinically and radiologically stable. Anaplastic ODGs, however, showed an initial increase followed by the fall of minimum ADC in all the 5 cases (P = 0.00). Four of the five cases developed progressive disease subsequently. In all the 4 GBM cases, a consistent fall of minimum ADC values was observed (P = 0.00), and they all progressed in spite of RT. Conclusions: The DWI-derived minimum ADC values are an important yet simple quantitative tool to assess the treatment response and disease progression before they are evident on conventional imaging during the follow-up of glial tumors.

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Apparent Diffusion Coefficient Decreases and Magnetic Resonance Imaging Perfusion Parameters are Associated in Ischemic Tissue of Acute Stroke Patients

Journal of Cerebral Blood Flow & Metabolism ◽

10.1097/00004647-200105000-00012 ◽

2001 ◽

Vol 21 (5) ◽

pp. 577-584 ◽

Cited By ~ 49

Author(s):

Jens Fiehler ◽

René Knab ◽

Jürgen R. Reichenbach ◽

Clemens Fitzek ◽

Cornelius Weiller ◽

...

Keyword(s):

Magnetic Resonance Imaging ◽

Diffusion Coefficient ◽

Magnetic Resonance ◽

Apparent Diffusion Coefficient ◽

Resonance Imaging ◽

Time To Peak ◽

Ischemic Tissue ◽

Apparent Diffusion ◽

Adc Values ◽

Weighted Magnetic Resonance Imaging

Perfusion-and diffusion-weighted magnetic resonance imaging scans are thought to allow the characterization of tissue at risk of infarction. The authors tested the hypothesis that the apparent diffusion coefficient (ADC) decrease should be associated with the severity of the perfusion deficit in ischemic tissue of acute stroke patients. Perfusion-and diffusion-weighted scans were performed in 11 patients with sudden onset of neurologic deficits within the last 6 hours and T2-weighted magnetic resonance imaging scans were obtained after 6 days. Parameter images of the maximum of the contrast agent concentration, time to peak, relative cerebral blood volume, relative cerebral blood flow, and relative mean transit time were computed from the perfusion-weighted data. A threshold function was used to identify tissue volumes with stepwise ADC decreases. An onionlike distribution of successively decreasing ADC values was found, with the lowest ADC in the center of the ischemic region. Correspondingly, tissue perfusion decreased progressively from the periphery toward the ischemic core. This effect was most pronounced in the time-to-peak maps, with a linear association between ADC decrease and time-to-peak increase. Apparent diffusion coefficient values decreased from the periphery toward the ischemic core, and this distribution of ADC values was strongly associated with the severity of the perfusion deficit.

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Magnetic Resonance Imaging Characterization of the Hippocampi in Temporal Lobe Epilepsy: Correlation of Volumetry and Apparent Diffusion Coefficient with Laterality and Duration of Seizures

Indian Journal of Radiology and Imaging ◽

10.1055/s-0041-1729672 ◽

2021 ◽

Author(s):

Apoorva Muralidhar ◽

Ashok Kumar ◽

Arjun Prakash ◽

Umesh Krishnamurthy ◽

Manjunath S. ◽

...

Keyword(s):

Magnetic Resonance Imaging ◽

Diffusion Coefficient ◽

Magnetic Resonance ◽

Apparent Diffusion Coefficient ◽

Temporal Lobe ◽

Volumetric Analysis ◽

Resonance Imaging ◽

Apparent Diffusion ◽

Adc Values ◽

The Right

Abstract Background and Purpose It is estimated that hippocampal damage is seen in 50 to 70% of patients with temporal lobe epilepsy (TLE). Although most magnetic resonance imaging (MRI) studies are adequate to detect gross hippocampal atrophy, subtle changes that may characterize early disease in TLE, such as visually nonappreciable volume loss, may often be missed if objective volumetric analysis is not undertaken. Materials and Methods We conducted a hospital-based prospective analytical study in which 40 patients with partial seizures of temporal lobe origin were included and their hippocampal volumes (HVs) were determined by manual volumetric analysis. The findings were recorded and correlated with the side of seizure and its duration. The quantitative assessment was allotted different grades accordingly. Also, the apparent diffusion coefficient (ADC) values of bilateral hippocampi were estimated and their correlation with the side of seizure was determined. Results Most patients in the study were in the age group of 11 to 20 years (37.5%). In total, 57.5% had seizures for a period of 1 to 5 years. While 67.5% (n = 27) had seizure on the right, 32.5% (n = 13) had on the left. The mean HV estimated on the right and left were correlated with the side of seizure and found to be statistically significant (p < 0.001 in those with right-sided seizures and p = 0.02 in those with left-sided seizures). Simultaneously the ADC values estimated were found to correlate with the laterality of seizures with a statistical difference (p < 0.01). Duration of seizures however did not show a positive correlation with the HV. Conclusion MRI with quantitative estimation of HV and ADC values can depict the presence and laterality in TLE with accuracy rates that exceed those achieved by visual inspection alone. Thus, quantitative MRI provides a useful means for translating volumetric analysis into clinical practice.

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