Reduced subarachnoid fluid diffusion in enlarged subarachnoid spaces of infancy

Background and purpose Enlargement of the subarachnoid spaces in infancy (ESSI) is a common cause of macrocephaly without proven explanation. We have observed subarachnoid diffusion to be decreased in these patients. We aim to quantify the diffusivity of ventricular and subarachnoid cerebrospinal fluid in ESSI patients, to determine if diffusion characteristics deviate from normocephalic infants, and to propose a unique mechanism for ESSI. Materials and methods 227 consecutive brain magnetic resonance exams from different macrocephalic children were retrospectively reviewed after institutional review board waiver. Patients with noncommunicating hydrocephalus, substantial ventriculomegaly, atrophy, structural bone and/parenchymal abnormalities, abnormal brain signal, hemorrhages, meningitis, and normal imaging were excluded. A total of 53 exams from macrocephalic patients and 21 normocephalic subjects were analyzed. Mean quantitative apparent diffusion coefficient (ADC) values were obtained from the ventricular frontal horn and frontal subarachnoid spaces. The subarachnoid:ventricular ADC ratios were compared using a Mann–Whitney U-test. Results The mean age was 13 +/−8 months (macrocephalic cohort) and 13 +/− 6 months (normocephalic cohort). The subarachnoid fluid mean ADC was 2.50+/−0.26 × 10−3 mm2/s in the macrocephalic group and 2.84+/−0.29 × 10−3 mm2/s in the normocephalic group. The ventricular fluid mean ADC was 2.97+/−0.37 × 10−3 mm2/s and 2.74 +/−0.32 × 10−6 mm2/s, respectively. The mean quantitative ADC ratios in the macrocephalic group were 0.85, significantly smaller than the normocephalic group (1) ( z = −6.3; p = 0). Conclusion Subarachnoid space fluid diffusivity is reduced in patients with enlarged subarachnoid spaces of infancy. We propose insufficient frontotemporal capillary protein resorption to be the initiating factor in ESSI, leading to unbalanced osmotic/hydrostatic pressures, and secondary congestion.

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Diagnostic value of apparent diffusion coefficient in differentiating between high-grade gliomas and brain metastases

Acta Radiologica ◽

10.1177/0284185117727787 ◽

2017 ◽

Vol 59 (5) ◽

pp. 599-605 ◽

Cited By ~ 15

Author(s):

Ionut Caravan ◽

Cristiana Augusta Ciortea ◽

Alexandra Contis ◽

Andrei Lebovici

Keyword(s):

Diffusion Coefficient ◽

Brain Metastases ◽

Apparent Diffusion Coefficient ◽

Curve Analysis ◽

High Grade ◽

Peritumoral Edema ◽

Roc Curve Analysis ◽

Apparent Diffusion ◽

Adc Values ◽

The Mean

Background High-grade gliomas (HGGs) and brain metastases (BMs) can display similar imaging characteristics on conventional MRI. In HGGs, the peritumoral edema may be infiltrated by the malignant cells, which was not observed in BMs. Purpose To determine whether the apparent diffusion coefficient values could differentiate HGGs from BMs. Material and Methods Fifty-seven patients underwent conventional magnetic resonance imaging (MRI) and diffusion-weighted imaging (DWI) before treatment. The minimum and mean ADC in the enhancing tumor (ADCmin, ADCmean) and the minimum ADC in the peritumoral region (ADCedema) were measured from ADC maps. To determine whether there was a statistical difference between groups, ADC values were compared. A receiver operating characteristic (ROC) curve analysis was used to determine the cutoff ADC value for distinguishing between HGGs and BMs. Results The mean ADCmin values in the intratumoral regions of HGGs were significantly higher than those in BMs. No differences were observed between groups regarding ADCmean values. The mean ADCmin values in the peritumoral edema of HGGs were significantly lower than those in BMs. According to ROC curve analysis, a cutoff value of 1.332 × 10−3 mm2/s for the ADCedema generated the best combination of sensitivity (95%) and specificity (84%) for distinguishing between HGGs and BMs. The same value showed a sensitivity of 95.6% and a specificity of 100% for distinguishing between GBMs and BMs. Conclusion ADC values from DWI were found to distinguish between HGGs and solitary BMs. The peritumoral ADC values are better than the intratumoral ADC values in predicting the tumor type.

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The Potential Role of Peritumoral Apparent Diffusion Coefficient Evaluation in Differentiating Glioblastoma and Solitary Metastatic Lesions of the Brain

Current Medical Imaging Formerly Current Medical Imaging Reviews ◽

10.2174/1573405617666210316120314 ◽

2021 ◽

Vol 17 ◽

Author(s):

Murat Tepe ◽

Suzan Saylisoy ◽

Ugur Toprak ◽

Ibrahim Inan

Keyword(s):

Diffusion Coefficient ◽

White Matter ◽

Apparent Diffusion Coefficient ◽

Sensitivity And Specificity ◽

Brain Mri ◽

Solitary Metastasis ◽

Metastatic Lesions ◽

Institutional Review ◽

Apparent Diffusion ◽

Adc Values

Objective: Differentiating glioblastoma (GBM) and solitary metastasis is not always possible using conventional magnetic resonance imaging (MRI) techniques. In conventional brain MRI, GBM and brain metastases are lesions with mostly similar imaging findings. In this study, we investigated whether apparent diffusion coefficient (ADC) ratios, ADC gradients, and minimum ADC values in the peritumoral edema tissue can be used to discriminate between these two tumors. Methods: This retrospective study was approved by the local institutional review board with a waiver of written informed consent. Prior to surgical and medical treatment, conventional brain MRI and diffusion-weighted MRI (b = 0 and b = 1000) images were taken from 43 patients (12 GBM and 31 solitary metastasis cases). Quantitative ADC measurements were performed on the peritumoral tissue from the nearest segment to the tumor (ADC1), the middle segment (ADC2), and the most distant segment (ADC3). The ratios of these three values were determined proportionally to calculate the peritumoral ADC ratios. In addition, these three values were subtracted from each other to obtain the peritumoral ADC gradients. Lastly, the minimum peritumoral and tumoral ADC values, and the quantitative ADC values from the normal appearing ipsilateral white matter, contralateral white matter and ADC values from cerebrospinal fluid (CSF) were recorded. Results: For the differentiation of GBM and solitary metastasis, ADC3 / ADC1 was the most powerful parameter with a sensitivity of 91.7% and specificity of 87.1% at the cut-off value of 1.105 (p < 0.001), followed by ADC3 / ADC2 with a cut-off value of 1.025 (p = 0.001), sensitivity of 91.7%, and specificity of 74.2%. The cut-off, sensitivity and specificity of ADC2 / ADC1 were 1.055 (p = 0.002), 83.3%, and 67.7%, respectively. For ADC3 – ADC1, the cut-off value, sensitivity and specificity were calculated as 150 (p < 0.001), 91.7% and 83.9%, respectively. ADC3 – ADC2 had a cut-off value of 55 (p = 0.001), sensitivity of 91.7%, and specificity of 77.4 whereas ADC2 – ADC1 had a cut-off value of 75 (p = 0.003), sensitivity of 91.7%, and specificity of 61.3%. Among the remaining parameters, only the ADC3 value successfully differentiated between GBM and metastasis (GBM 1802.50 ± 189.74 vs. metastasis 1634.52 ± 212.65, p = 0.022). Conclusion: The integration of the evaluation of peritumoral ADC ratio and ADC gradient into conventional MR imaging may provide valuable information for differentiating GBM from solitary metastatic lesions.

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Use of apparent diffusion coefficients in evaluating the response of vestibular schwannomas to Gamma Knife surgery

Journal of Neurosurgery ◽

10.3171/2012.7.gks121003 ◽

2012 ◽

Vol 117 (Special_Suppl) ◽

pp. 63-68 ◽

Cited By ~ 9

Author(s):

Chun-Chao Chuang ◽

Cheng-Siu Chang ◽

Yu-Sheng Tyan ◽

Keh-Shih Chuang ◽

Hsien-Tang Tu ◽

...

Keyword(s):

Mr Imaging ◽

Diffusion Coefficients ◽

Tumor Volume ◽

Imaging Studies ◽

Adc Value ◽

Apparent Diffusion Coefficients ◽

Apparent Diffusion ◽

Adc Values ◽

The Mean

Object Cellular density is a major factor responsible for changes in apparent diffusion coefficients (ADCs). The authors hypothesized that loss of tumor cells after Gamma Knife surgery (GKS) might alter ADC values. Magnetic resonance imaging, including diffusion-weighted (DW) imaging, was performed to detect cellular changes in brain tumors so that the authors could evaluate the tumor response to GKS as well as the efficacy of the procedure. Methods The authors conducted a prospective trial involving 31 patients harboring solid or cystic vestibular schwannomas (VSs) that were treated with GKS. The patients underwent serial MR imaging, including DW imaging, before GKS and at multiple intervals following the procedure. The authors observed the patients over time, evaluating MR imaging findings and clinical outcomes at 6-month intervals. The ADCs were calculated from echo-planar DW images, and mean ADC values were compared at each follow-up. Results The mean follow-up period was 36.5 months (range 18–60 months). Imaging studies showed a reduction in tumor volume in 19 patients (61.3%) and tumor growth arrest in 9 patients (29%). In the remaining 3 patients (9.7%), tumor enlargement was documented at 18, 36, and 42 months. The mean ADC value before GKS for all solid VSs was 1.06 ± 0.17 × 10−3 mm2/second, which significantly increased 6 months after GKS and continued to increase with time (p = 0.0086). The mean ADC value for treated solid tumors as of the last mean follow-up of 36 months (range 18–60 months) was 1.72 ± 0.26 × 10−3 mm2/second (range 1.50–2.09 × 10−3 mm2/second), which was significantly higher than that before GKS (p = 0.0001). Tumor volumes were positively related to ADC values (p = 0.03). The mean ADC value before GKS for all cystic VSs was 2.09 ± 0.24 × 10−3 mm2/second (range 1.80–2.58 × 10−3 mm2/second). The mean ADC value for treated cystic tumors as of the last mean follow-up of 38 months (range 18–48 months) was 1.89 ± 0.22 × 10−3 mm2/second. In 3 patients harboring solid VSs, the tumor enlarged after GKS but the ADC values were higher than those before GKS. The authors considered these tumors to be controlled and continued follow-up in the patients. Conclusions Apparent diffusion coefficient values may be useful for evaluating treatment results before any definite volume change is detected on imaging studies and for distinguishing radiation-induced necrosis from tumor recurrence in cases in which other imaging results are not definitive, as in cases of increased tumor volume or no volume change. The authors suggest that ADC measurements be included during routine MR imaging examinations for the evaluation of GKS results.

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Differentiation of prostate cancer and stromal hyperplasia in the transition zone with histogram analysis of the apparent diffusion coefficient

Acta Radiologica ◽

10.1177/0284185117698861 ◽

2017 ◽

Vol 58 (12) ◽

pp. 1528-1534 ◽

Cited By ~ 4

Author(s):

Liu Xiaohang ◽

Zhou Bingni ◽

Zhou Liangping ◽

Peng Weijun ◽

Yang Xiaoqun ◽

...

Keyword(s):

Prostate Cancer ◽

Diffusion Coefficient ◽

Apparent Diffusion Coefficient ◽

Transition Zone ◽

B Value ◽

Histogram Analysis ◽

Apparent Diffusion ◽

Adc Values ◽

The Mean ◽

Magnetic Resonance Imaging Mri

Background Prostate cancer and stromal hyperplasia (SH) in the transition zone (TZ) are difficult to discriminate by conventional magnetic resonance imaging (MRI) and diffusion-weighted imaging (DWI). Purpose To investigate the apparent diffusion coefficient (ADC) of prostate cancer and SH in the TZ with histogram analysis and the ability of ADC metrics to differentiate between these two tissues. Material and Methods Thirty-three cancer and 29 SH lesions in the TZ of 54 patients undergoing preoperative DWI (b-value 0, 1000 s/mm2) were analyzed. All the lesions on the MR images were localized based on histopathologic correlations. The 10th, 25th, and 50th percentiles, and the mean ADC values were calculated for the two tissues and compared. The efficiencies of the 10th, 25th, and 50th ADC percentiles in differentiating the two tissues were compared with that of the mean ADC with receiver operating characteristic (ROC) analysis. Results The 10th, 25th, and 50th percentiles and mean ADC values (×10−3 mm2/s) were 0.86 ± 0.15, 0.89 ± 0.16, 0.94 ± 0.16, and 1.03 ± 0.17 in SH and 0.64 ± 0.12, 0.69 ± 0.12, 0.72 ± 0.16, and 0.83 ± 0.15 in TZ cancer, respectively. The parameters were all significantly lower in cancer than SH. The 10th ADC percentile yielded an area under the ROC curve (AUC) of 0.87 for the differentiation of carcinomas from SH, which was higher than the mean ADC (0.80) ( P < 0.05), and the AUCs of the 25th (0.82) and 50th (0.83) percentiles exhibited no differences from those of the mean ADC ( P > 0.05). Conclusion Histogram analysis of ADC values may potentially improve the differentiation of prostate cancer from SH in the TZ.

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Initial experience of 3-tesla apparent diffusion coefficient values in characterizing squamous cell carcinomas of the head and neck

Acta Radiologica ◽

10.1080/02841850802406196 ◽

2008 ◽

Vol 49 (9) ◽

pp. 1079-1084 ◽

Cited By ~ 20

Author(s):

A. Srinivasan ◽

R. Dvorak ◽

S. Rohrer ◽

S.K. Mukherji

Keyword(s):

Head And Neck ◽

Masseter Muscle ◽

Squamous Cell Carcinomas ◽

Paraspinal Muscles ◽

Adc Value ◽

Normal Neck ◽

Apparent Diffusion ◽

Adc Values ◽

The Mean ◽

Base Of The Tongue

Background: With the increased clinical use of 3-Tesla (3T) magnets, it becomes important to identify the potential applications of advanced magnetic resonance (MR) imaging techniques such as diffusion-weighted imaging in head and neck pathologies. Purpose: To establish the 3T apparent diffusion coefficient (ADC) values for normal neck structures, and to examine the utility of ADC values in distinguishing head and neck squamous cell carcinomas (HNSCC) from normal neck anatomy. Material and Methods: 3T diffusion-weighted imaging was performed on 10 normal volunteers and 10 patients with known HNSCC. In the volunteers, mean ADC was calculated in the parotid gland, submandibular gland, base of the tongue, pterygoid muscle, masseter muscle, paraspinal muscles, true vocal cord, thyroid gland, thyroid cartilage, cricoid cartilage, and lymph nodes. The mean tumor ADC value was calculated from the 10 patients with HNSCC and compared with the normal ADC values from various neck structures. Results: The mean ADC value measured in the HNSCC was 1.101 (±0.214)×10−3mm2/s. This was significantly lower than ADC values of paraspinal muscles, pterygoid muscle, masseter muscle, thyroid gland, and base of the tongue ( P=0.0006, 0.0002, 0.0001, 0.001, and 0.002, respectively). The tumor ADC values were not significantly different from ADC values of parotid and submandibular glands ( P=0.057 and 0.14, respectively). Conclusion: 3T ADC values show potential for distinguishing HNSCC from normal extracranial head and neck structures.

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Can apparent diffusion coefficient (ADC) distinguish breast cancer from benign breast findings? A meta-analysis based on 13 847 lesions

BMC Cancer ◽

10.1186/s12885-019-6201-4 ◽

2019 ◽

Vol 19 (1) ◽

Cited By ~ 7

Author(s):

Alexey Surov ◽

Hans Jonas Meyer ◽

Andreas Wienke

Keyword(s):

Diffusion Coefficient ◽

Meta Analysis ◽

Mean Value ◽

Breast Lesions ◽

Benign Lesions ◽

B Values ◽

Apparent Diffusion ◽

Adc Values ◽

Malignant Lesions ◽

The Mean

Abstract Background The purpose of the present meta-analysis was to provide evident data about use of Apparent Diffusion Coefficient (ADC) values for distinguishing malignant and benign breast lesions. Methods MEDLINE library and SCOPUS database were screened for associations between ADC and malignancy/benignancy of breast lesions up to December 2018. Overall, 123 items were identified. The following data were extracted from the literature: authors, year of publication, study design, number of patients/lesions, lesion type, mean value and standard deviation of ADC, measure method, b values, and Tesla strength. The methodological quality of the 123 studies was checked according to the QUADAS-2 instrument. The meta-analysis was undertaken by using RevMan 5.3 software. DerSimonian and Laird random-effects models with inverse-variance weights were used without any further correction to account for the heterogeneity between the studies. Mean ADC values including 95% confidence intervals were calculated separately for benign and malign lesions. Results The acquired 123 studies comprised 13,847 breast lesions. Malignant lesions were diagnosed in 10,622 cases (76.7%) and benign lesions in 3225 cases (23.3%). The mean ADC value of the malignant lesions was 1.03 × 10− 3 mm2/s and the mean value of the benign lesions was 1.5 × 10− 3 mm2/s. The calculated ADC values of benign lesions were over the value of 1.00 × 10− 3 mm2/s. This result was independent on Tesla strength, choice of b values, and measure methods (whole lesion measure vs estimation of ADC in a single area). Conclusion An ADC threshold of 1.00 × 10− 3 mm2/s can be recommended for distinguishing breast cancers from benign lesions.

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Measurement of Apparent Diffusion Coefficient (ADC) Values of Ependymoma and Medulloblastoma Tumors: a Patient-based Study

Journal of Biomedical Physics and Engineering ◽

10.31661/jbpe.v0i0.889 ◽

2019 ◽

Author(s):

H Taheri ◽

M B Tavakoli

Keyword(s):

Diffusion Coefficient ◽

Apparent Diffusion Coefficient ◽

Pediatric Patients ◽

Clinical Images ◽

Adc Value ◽

Conventional Mri ◽

Apparent Diffusion ◽

Adc Values ◽

The Mean ◽

Magnetic Resonance Imaging Mri

Background: aimed to compare the apparent diffusion coefficient (ADC) of two different cerebellar pediatric tumors, including ependymoma and medulloblastoma which have shown similar clinical images in conventional magnetic resonance imaging (MRI) methods.Material and Methods: Thirty six pediatric patients who were suspected to have the mentioned tumors according to their CT image findings were included in this study. The patients were subjected to conventional MRI protocols followed by diffusion weighted imaging (DWI) and ADC values of the tumors were calculated automatically using MRI scanner software.Results: The mean (± SD) ADC value for ependymoma (1.2± 0.06 ×10-3 mm2/s) was significantly higher than medulloblastoma (0.87 ± 0.02 ×10-3 mm2/s) (p = 0.041). Moreover, the maximum ADC value of ependymoma was considerably different in comparison with medulloblastoma (1.4 ×10-3 mm2/s and 0.96×10-3 mm2/s, respectively; p = 0.035) Furthermore, the minimum ADC value of ependymoma was higher compared to medulloblastoma (1.0 ×10-3 mm2/s and 0.61×10-3 mm2/s, respectively), but it was not significant (p = 0.067).Conclusion: Evaluation of ADC values for ependymoma and medulloblastoma is a reliable method to differentiate these two malignancies. This is due to different ADC values reflected during the evaluation.

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Apparent diffusion coefficients for evaluation of the response of brain tumors treated by Gamma Knife surgery

Journal of Neurosurgery ◽

10.3171/2010.7.gks10864 ◽

2010 ◽

Vol 113 (Special_Supplement) ◽

pp. 97-104 ◽

Cited By ~ 10

Author(s):

Chuan-Fu Huang ◽

Shyh-Ying Chiou ◽

Ming-Fang Wu ◽

Hsien-Tang Tu ◽

Wen-Shan Liu ◽

...

Keyword(s):

Mr Imaging ◽

Diffusion Coefficients ◽

Tumor Recurrence ◽

Adc Value ◽

Apparent Diffusion Coefficients ◽

Acoustic Neuromas ◽

Apparent Diffusion ◽

Adc Values ◽

The Mean

Object Cellular density is a major factor for change in the apparent diffusion coefficient (ADC). The authors hypothesized that loss of tumor cells after Gamma Knife surgery (GKS) may alter the ADC value and used diffusion weighted MR imaging (DW imaging) to evaluate cellular changes in brain tumors to detect their treatment response and the efficacy of GKS. Methods In this paper the authors describe a prospective trial involving 86 patients harboring 38 solid or predominantly solid brain metastases, 30 meningiomas, and 24 acoustic neuromas that were treated by GKS. The patients underwent serial MR imaging examinations, including DW imaging, before treatment and at multiple intervals following GKS. Follow-up MR images and clinical outcomes were reviewed at 3-month intervals for metastatic lesions and at 6-month intervals for benign tumors. Apparent diffusion coefficients were calculated from echoplanar DW images, and mean ADC values were compared at each follow-up. Results The mean ADC value for all meningiomas was 0.82 ± 0.15 × 10−3 mm2/sec before GKS. The mean ADC value as of the last mean follow-up of 42 months was 1.36 ± 0.19 × 10−3 mm2/sec, a significant increase compared to that before treatment (p < 0.0001). Calcification (p = 0.006) and tumor recurrence (p = 0.025) significantly prevented a rise in the ADC level. The mean ADC value for all solid acoustic neuromas was 1.06 ± 0.17 × 10−3 mm2/sec before GKS. The mean ADC value as of the last mean follow-up of 36 months was 1.72 ± 0.26 × 10−3 mm2/sec, a significant increase (p = 0.0002) compared with values before GKS. At the last mean MR imaging follow-up there appeared to be tumor enlargement in 3 patients (12.5%); however, since the ADC values in these patients were significantly higher than the preradiosurgery values, the finding was considered to be a sign of radiation necrosis rather than tumor recurrence. The mean ADC value of metastatic tumors was 1.05 ± 0.12 × 10−3 mm2/sec before GKS. This value rose significantly (p < 0.0001) to 1.64 ± 0.18 × 10−3 mm2/sec after GKS at a mean follow-up of 9.4 months. Magnetic resonance imaging showed that 89% of these tumors had been controlled by GKS. In 2 patients there were enlarged lesions, but the ADC values were the same as pre-GKS levels, and therefore, the lesions were deemed recurrent. Conclusions Apparent diffusion coefficient values may be useful in evaluating treatment results before a definitive change in volume is evident on imaging studies. In some patients in whom imaging findings are equivocal, ADC values may also be used to distinguish radiation-induced necrosis from tumor recurrence.

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Apparent diffusion coefficient (ADC) values of serous, endometrioid, and clear cell carcinoma of the ovary: pathological correlation

Acta Radiologica ◽

10.1177/0284185119883392 ◽

2019 ◽

Vol 61 (7) ◽

pp. 992-1000 ◽

Cited By ~ 1

Author(s):

Takafumi Ono ◽

Keiko Kishimoto ◽

Shinya Tajima ◽

Ichiro Maeda ◽

Masayuki Takagi ◽

...

Keyword(s):

Ovarian Cancer ◽

Diffusion Coefficient ◽

Apparent Diffusion Coefficient ◽

Epithelial Ovarian Cancer ◽

Cell Carcinoma ◽

Clear Cell ◽

Clear Cell Carcinoma ◽

Apparent Diffusion ◽

Adc Values ◽

The Mean

Background Primary epithelial ovarian cancer is divided into several subtypes. The relationships between apparent diffusion coefficient (ADC) values and their subtypes have not yet been established. Purpose To investigate whether ADC values of epithelial ovarian cancer vary according to histologic tumor cellularity and evaluate the difference of clear cell carcinoma (CCC), high-grade serous carcinoma (HGSC), and endometrioid carcinoma (EC). Material and Methods This retrospective study included 51 cases of epithelial ovarian cancer (17 CCC, 20 HGSC, and 14 EC) identified by magnetic resonance imaging with pathological confirmation. All patients underwent diffusion-weighted imaging and the ADC values of lesions were measured. We counted the tumor cells in three high-power fields and calculated the average for each case. The Spearman’s correlation coefficient test was used to analyze correlation between ADC values and tumor cellularity. The ADC values of HGSC, EC, and CCC were compared using the Steel–Dwass test. Results The ADC values of all cases were significantly inversely correlated with tumor cellularity ( rs = −0.761; P < 0.001). The mean ± SD ADC values (×10−3 mm2/s) of CCC, HGSC, and EC were 1.24 ± 0.17 (range 0.98--1.65), 0.84 ± 0.10 (range 0.67--1.06), and 0.84 ± 0.10 (range 0.67--1.07). The mean ± SD tumor cellularity of CCC, HGSC, and EC was 162.88 ± 63.28 (range 90.33--305.67), 440.60 ± 119.86 (range 204.67--655.67), and 461.02 ± 81.86 (range 333.33--602.33). Conclusion There is a significant inverse correlation between ADC values and tumor cellularity in epithelial ovarian cancer. The mean ADC value of CCC was higher than those of HGSC and EC, seemingly due to the low cellularity of CCC.

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Role of Diffusion-Weighted MR Imaging in Characterization of Posterior Fossa Tumors

AL-Kindy College Medical Journal ◽

10.47723/kcmj.v14i1.9 ◽

2018 ◽

Vol 14 (1) ◽

pp. 8-12

Author(s):

Lubna Ali Hussain

Keyword(s):

Diffusion Coefficient ◽

Mr Imaging ◽

Apparent Diffusion Coefficient ◽

Posterior Fossa ◽

Solid Tumor ◽

Posterior Fossa Tumors ◽

Adc Value ◽

Apparent Diffusion ◽

Adc Values ◽

The Mean

Background: Conventional MR imaging is essential for diagnosis and evaluation of the posterior fossa tumors Objectives: To assess the value of diffusion weighted imaging and apparent diffusion coefficient in making distinction between different histological types of posterior fossa tumors. Type of the study: Cross-sectional study. Methods: Brain MRI and DWI assessed 19 patients (12 female and 7 male) with MRI diagnosis of posterior fossa tumors. absolute ADC values of contrast -enhancing solid tumor region and ADC ratio of solid tumor to ADC of normal -appearing deep White matter were compared with histological diagnosis postoperatively .The mean ADC value and ratio were determined by using a 2-tailed T test. Results: In eight of medulloblastoma ,The mean ADC value was 0.67±0.14x 10-3 mm 2/s and ratio 0.86±0.19 , ependymoma (n=3), ADC value 1.09 ±0.14 x10 -3 mm 2 /s and ratio 1,43±0.13 , pilocytic astrocytoma (n=4) ADC value 1,72 ±0.27x10 -3 mm2/s and ratio 2.19±0.4, brainstem glioma (n=2) with ADC value1.18±0.06 x10-3mm2/s and ratio 1.64±0.08 , haemangioblastoma (n=1) with ADC value1.46x10-1mm2/s and ratio 1.87 , and meningioma with ADC value 0.72x10-3mm2/s and ratio 0.85. ADC values were higher in JPA than in ependymomas and medulloblastoma (P value <o,o5).ADC ratio were also statistically significant difference among these three tumors type . Conclusion: calculation of apparent diffusion coefficient value in the solid enhancing portion of tumor seems to be reliable for differentiate between medulloblastoma at one end and , juvenile pilocytic astrocytoma (JPA) and ependymoma at other end as the former has ADC of < 1 while other tumors have ADC value of >1.

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