Prediction of recurrence in solid nonfunctioning pituitary macroadenomas: additional benefits of diffusion-weighted MR imaging

2020 ◽  
Vol 132 (2) ◽  
pp. 351-359 ◽  
Author(s):  
Ching-Chung Ko ◽  
Tai-Yuan Chen ◽  
Sher-Wei Lim ◽  
Yu-Ting Kuo ◽  
Te-Chang Wu ◽  
...  
Keyword(s):  
Mr Imaging ◽  
Cox Proportional Hazards ◽  
Imaging Features ◽  
Large Tumor ◽  
Adc Value ◽  
Diffusion Weighted ◽  
Increased Risk ◽  
Adc Values ◽  
Pituitary Macroadenomas

OBJECTIVEA subset of benign, nonfunctioning pituitary macroadenomas (NFMAs) has been shown to undergo early progression/recurrence (P/R) during the first years after surgical resection. The aim of this study was to determine preoperative MR imaging features for the prediction of P/R in benign solid NFMAs, with emphasis on apparent diffusion coefficient (ADC) values.METHODSWe retrospectively investigated the preoperative MR imaging features for the prediction of P/R in benign solid NFMAs. Only the patients who had undergone preoperative MRI and postoperative MRI follow-ups for more than 1 year (at least every 6–12 months) were included. From November 2010 to December 2016, a total of 30 patients diagnosed with benign solid NFMAs were included (median follow-up time 45 months), and 19 (63.3%) patients had P/R (median time to P/R 24 months).RESULTSBenign solid NFMAs with cavernous sinus invasion, failed chiasmatic decompression, large tumor height and tumor volume, high diffusion-weighted imaging (DWI) signal, and lower ADC values/ratios were significantly associated with P/R (p < 0.05). The cutoff points of ADC value and ADC ratio for prediction of P/R are 0.77 × 10−3 mm2/sec and 1.01, respectively, with area under the curve (AUC) values (0.9 and 0.91) (p < 0.01). In multivariate Cox proportional hazards analysis, low ADC value (< 0.77 × 10−3 mm2/sec) is a high-risk factor of P/R (p < 0.05) with a hazard ratio of 14.07.CONCLUSIONSBenign solid NFMAs with low ADC values/ratios are at a significantly increased risk of P/R, and aggressive treatments accompanied by close follow-up with imaging studies should be considered.

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

2012 ◽  
Vol 117 (Special_Suppl) ◽  
pp. 63-68 ◽  
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.

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

2010 ◽  
Vol 113 (Special_Supplement) ◽  
pp. 97-104 ◽  
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.

scholarly journals Changes of cerebrospinal fluid in the upper neck area with age using diffusion weighted MR imaging

2018 ◽  
Vol 5 (1) ◽  
pp. 20
Author(s):  
Ichiro Ogura ◽  
Takaaki Oda ◽  
Mikiko Sue ◽  
Yoshihiko Sasaki
Keyword(s):  
Spinal Cord ◽  
Cerebrospinal Fluid ◽  
Mr Imaging ◽  
Clinical Settings ◽  
Significant Relation ◽  
Adc Value ◽  
Diffusion Weighted ◽  
Neck Area ◽  
Apparent Diffusion ◽  
Adc Values

Purpose: Few studies have concerned the absolute apparent diffusion coefficient (ADC) values in the normal cerebrospinal fluid in the upper neck area and the effect of aging on diffusion. The purpose of this study was to evaluate changes of cerebrospinal fluid in the upper neck area with age using diffusion weighted MR imaging (DWI).Methods and methods: Our study included 160 patients who underwent MR imaging for oral and maxillofacial diseases. All patients were examined by DWI with 2 b values (0 and 800 sec/mm2) at 1.5 Tesla and ADC maps. The cerebrospinal fluid and spinal cord in the upper neck area were analyzed using the ADC values and age.Results: ADC value of cerebrospinal fluid was significantly correlated to ADC value of spinal cord (R2 = 0.141, p = .000). ADC value of spinal cord had no relation to age (R2 = 0.015, p = .125). ADC value of cerebrospinal fluid had significant relation to age (R2= 0.026, p = .042).Conclusions: We indicated the changes of cerebrospinal fluid in the upper neck area with age using DWI. The data reported herein are representative, and the ADC values can be used for reference in future studies and in clinical settings.

scholarly journals Quantitative Evaluation for Differential Diagnosis of Breast Lesions in Diffusion-Weighted MR Imaging

2021 ◽  
Author(s):  
Winniecia Dkhar ◽  
Rajagopal Kadavigere ◽  
Samir Paruthikunnan Mustaffa
Keyword(s):  
Differential Diagnosis ◽  
Mr Imaging ◽  
B Value ◽  
Breast Lesions ◽  
Benign Lesions ◽  
Adc Value ◽  
B Values ◽  
Diffusion Weighted ◽  
Adc Values ◽  
Malignant Lesions

AbstractDiffusion-weighted MR Imaging is a rapidly emerging technique, that allows in-vivo mapping processes of the water diffusion in tissues. It has the potential capabilities for clinical application in breast imaging. The aim of this study was to find out the optimal b-value for calculation of ADC value for differential diagnosis of breast lesions. A total of 124 subjects (mean age 46 years) with 141 lesions were included. The protocol consists of axial T2 sequence for lesion localization and measurement and DW sequence with three sets of b-values of 0, 300, 600, and 1000 s/mm2. The mean ADC values of the breast lesions for b-values (0, 300, 600, and 1000) were 1.75 ± 0.18 × 10−3mm2/sec, 1.66 ± 0.12 × 10−3mm2/sec and 1.57 ± 0.15 × 10−3mm2/sec for the benign lesions and 1.26 ± 0.048 × 10−3mm2/sec, 1.14 ± 0.11 × 10−3mm2/sec and 0.93 ± 0.14 × 10−3mm2/sec for malignant lesions respectively. Statistical significant differences were noted on the ADC value of benign and malignant lesions among the three sets of b values (p = 0.001). ADC values of malignant lesion was significantly lower compared to benign lesions. The AUC (0.998) was substantially large for b-value of 0,600 s/mm2 with a threshold ADC cut off value of 1.28 × 10−3mm2/sec with 98.4% sensitivity, 93.2% specificity and 98.5% positive predictive value(PPV). In conclusion, diffusion weighted imaging has the ability for differential diagnosis of breast lesions with the optimal b value of 0,600 s/ mm2. DWI is a reliable tool for characterising breast lesions and may increase the overall specificity of breast MRI.

scholarly journals Role of diffusion weighted MR imaging in differentiating benign from malignant prostate lesions

2019 ◽  
Vol 7 (6) ◽  
pp. 2341
Author(s):  
Sachin . ◽  
Kirti Chaturvedy ◽  
R. N. Gehlot ◽  
Prateek Sihag ◽  
Suman Kumari ◽  
...  
Keyword(s):  
Mr Imaging ◽  
Diagnostic Accuracy ◽  
Chronic Prostatitis ◽  
Benign Lesion ◽  
Malignant Lesion ◽  
Adc Value ◽  
Diffusion Weighted ◽  
Adc Values ◽  
The Mean ◽  
Sensitivity Specificity

Background: The purpose of the study was to determine the diagnostic accuracy of diffusion weighted MR imaging and to propose a cut off ADC value in differentiating benign from malignant prostatic lesions considering histopathology as gold standard.Methods: It is a descriptive type of observational study done on 40 patients with clinical suspicion of prostate carcinoma and elevated PSA level more than 4ng/ml. The patients underwent Multiparametric prostate MRI and ADC values were calculated using ADC maps.Results: Of the 40 cases included in the study histopathology revealed a diagnosis of abscess (1), chronic prostatitis (2), BPH with chronic prostatitis (4), BPH (12), and malignancy (21). The mean and standard deviation (SD) of ADC values for the abscess (0.59), CP (0.83+0.16), BPH with CP (0.94+0.22), BPH (1.14+0.14) and malignancy (0.72+0.15) (x10-3mm2/s) were found in our study. The mean ADC value of malignant lesion was lower (0.727+0.149) as compare to benign lesion (1.034+0.216) and this difference was found to be statistically significant with p<0.001. By using ROC curve, ADC cut off value was calculated as 0.92 x 10-3mm2/s and sensitivity, specificity at this cut off value of ADC were 95.24% and 73.68% respectively. The PPV, NPV, diagnostic accuracy of at this cut off value of ADC were 80%, 93.33%, 85% respectively.Conclusions: Our study shows that DWI with ADC calculation helps in differentiation of Benign from Malignant prostatic lesions with high accuracy and this quantitative analysis should be incorporated in routine MRI evaluation of prostatic lesions

scholarly journals Role of Quantitative Diffusion-Weighted Imaging in Differentiating Benign and Malignant Orbital Masses

2021 ◽  
Author(s):  
Preeti Mundhada ◽  
Sudarshan Rawat ◽  
Ullas Acharya ◽  
Dhananjay Raje
Keyword(s):  
Roc Curve ◽  
Diffusion Weighted Imaging ◽  
Care Hospital ◽  
Adc Value ◽  
Diffusion Weighted ◽  
Significant Difference ◽  
Orbital Masses ◽  
Adc Values ◽  
Orbital Lesions

Abstract Aim To determine the role of diffusion-weighted imaging (DWI) with apparent diffusion coefficient (ADC) values in differentiating benign and malignant orbital masses. Materials and Methods After obtaining institutional ethical board approval and informed consent from all patients, an observational study was done for a period of 24 months in the radiology department of a tertiary care hospital in South India. Conventional magnetic resonance imaging and DWI using a 3T scanner was done for all patients with suspected orbital mass lesion. ADC value and clinicohistopathological correlation were studied for every patient. Chi-square test was used to compare the signal characteristics of DWI and ADC maps between benign and malignant lesions. A comparison of mean ADC values for benign and malignant masses was performed using Student’s t-test for independent samples. The cut-off value for ADC was obtained using the receiver operating characteristic (ROC) curve. Results Of 44 patients with orbital lesions, 70% were benign and 30% were malignant. There was a significant difference in the mean ADC values of benign and malignant orbital masses. Using ROC curve analysis, an optimal ADC threshold of 1.26 × 10−3 mm2/s was calculated for the prediction of malignancy with 100% sensitivity, 80.65% specificity, and 86.36% accuracy (95% confidence interval: 0.872, 1.00, p < 0.0001). Two ADC thresholds were used to characterize the orbital masses with more than 90% confidence. Conclusion Quantitative assessment of ADC is a useful noninvasive diagnostic tool for differentiating benign and malignant orbital masses. Malignant orbital lesions demonstrate significantly lower ADC values as compared with benign lesions.

scholarly journals Elevated plasma growth and differentiation factor 15 predicts incident anemia in older adults aged 60 years and older

2020 ◽  
Author(s):  
Yuko Yamaguchi ◽  
Marta Zampino ◽  
Toshiko Tanaka ◽  
Stefania Bandinelli ◽  
Yusuke Osawa ◽  
...  
Keyword(s):  
Older Adults ◽  
Proportional Hazards ◽  
Proportional Hazards Model ◽  
Cox Proportional Hazards ◽  
Cox Proportional Hazards Model ◽  
Differentiation Factor ◽  
Hazards Model ◽  
Increased Risk ◽  
The Relationship

Abstract Background Anemia is common in older adults and associated with greater morbidity and mortality. The causes of anemia in older adults have not been completely characterized. Although elevated circulating growth and differentiation factor 15 (GDF-15) has been associated with anemia in older adults, it is not known whether elevated GDF-15 predicts the development of anemia. Methods We examined the relationship between plasma GDF-15 concentrations at baseline in 708 non-anemic adults, aged 60 years and older, with incident anemia during 15 years of follow-up among participants in the Invecchiare in Chianti (InCHIANTI) Study. Results During follow-up, 179 (25.3%) participants developed anemia. The proportion of participants who developed anemia from the lowest to highest quartile of plasma GDF-15 was 12.9%, 20.1%, 21.2%, and 45.8%, respectively. Adults in the highest quartile of plasma GDF-15 had an increased risk of developing anemia (Hazards Ratio 1.15, 95% Confidence Interval 1.09, 1.21, P&lt;.0001) compared to those in the lower three quartiles in a multivariable Cox proportional hazards model adjusting for age, sex, serum iron, soluble transferrin receptor, ferritin, vitamin B12, congestive heart failure, diabetes mellitus, and cancer. Conclusions Circulating GDF-15 is an independent predictor for the development of anemia in older adults.

scholarly journals Sex-Specific Associations between Blood Pressure and Risk of Atrial Fibrillation Subtypes in the Tromsø Study

2021 ◽  
Vol 10 (7) ◽  
pp. 1514
Author(s):  
Hilde Espnes ◽  
Jocasta Ball ◽  
Maja-Lisa Løchen ◽  
Tom Wilsgaard ◽  
Inger Njølstad ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Blood Pressure ◽  
Proportional Hazards ◽  
Cox Proportional Hazards ◽  
Pressure Management ◽  
Reference Models ◽  
Proportional Hazards Regression ◽  
Hazard Ratios ◽  
Increased Risk

The aim of this study was to explore sex-specific associations between systolic blood pressure (SBP), hypertension, and the risk of incident atrial fibrillation (AF) subtypes, including paroxysmal, persistent, and permanent AF, in a general population. A total of 13,137 women and 11,667 men who participated in the fourth survey of the Tromsø Study (1994–1995) were followed up for incident AF until the end of 2016. Cox proportional hazards regression analysis was conducted using fractional polynomials for SBP to provide sex- and AF-subtype-specific hazard ratios (HRs) for SBP. An SBP of 120 mmHg was used as the reference. Models were adjusted for other cardiovascular risk factors. Over a mean follow-up of 17.6 ± 6.6 years, incident AF occurred in 914 (7.0%) women (501 with paroxysmal/persistent AF and 413 with permanent AF) and 1104 (9.5%) men (606 with paroxysmal/persistent AF and 498 with permanent AF). In women, an SBP of 180 mmHg was associated with an HR of 2.10 (95% confidence interval [CI] 1.60–2.76) for paroxysmal/persistent AF and an HR of 1.80 (95% CI 1.33–2.44) for permanent AF. In men, an SBP of 180 mmHg was associated with an HR of 1.90 (95% CI 1.46–2.46) for paroxysmal/persistent AF, while there was no association with the risk of permanent AF. In conclusion, increasing SBP was associated with an increased risk of both paroxysmal/persistent AF and permanent AF in women, but only paroxysmal/persistent AF in men. Our findings highlight the importance of sex-specific risk stratification and optimizing blood pressure management for the prevention of AF subtypes in clinical practice.

scholarly journals Association of oral contraceptives and tubal ligation with risk of early natural menopause

2021 ◽  
Author(s):  
C R Langton ◽  
B W Whitcomb ◽  
A C Purdue-Smithe ◽  
L L Sievert ◽  
S E Hankinson ◽  
...  
Keyword(s):  
Oral Contraceptives ◽  
Proportional Hazards ◽  
Reproductive Factors ◽  
Cox Proportional Hazards ◽  
Tubal Ligation ◽  
Health Study ◽  
Early Menopause ◽  
Natural Menopause ◽  
Increased Risk

Abstract STUDY QUESTION What is the association of oral contraceptives (OCs) and tubal ligation (TL) with early natural menopause? SUMMARY ANSWER We did not observe an association of OC use with risk of early natural menopause; however, TL was associated with a modestly higher risk. WHAT IS KNOWN ALREADY OCs manipulate hormone levels, prevent ovulation, and may modify the rate of follicular atresia, while TL may disrupt the blood supply to the ovaries. These mechanisms may be associated with risk of early menopause, a condition associated with increased risk of cardiovascular disease and other adverse health outcomes. STUDY DESIGN, SIZE, DURATION We examined the association of OC use and TL with natural menopause before the age of 45 years in a population-based study within the prospective Nurses’ Health Study II (NHSII) cohort. Participants were followed from 1989 to 2017 and response rates were 85-90% for each cycle. PARTICIPANTS/MATERIALS, SETTING, METHODS Participants included 106 633 NHSII members who were premenopausal and aged 25-42 years at baseline. Use, duration and type of OC, and TL were measured at baseline and every 2 years. Menopause status and age were assessed every 2 years. Follow-up continued until early menopause, age 45 years, hysterectomy, oophorectomy, death, cancer diagnosis, or loss to follow-up. We used Cox proportional hazards models to estimate hazard ratios (HRs) and 95% CIs adjusted for lifestyle, dietary, and reproductive factors. MAIN RESULTS AND THE ROLE OF CHANCE Over 1.6 million person-years, 2579 members of the analytic cohort experienced early natural menopause. In multivariable models, the duration, timing, and type of OC use were not associated with risk of early menopause. For example, compared with women who never used OCs, those reporting 120+ months of OC use had an HR for early menopause of 1.01 (95% CI, 0.87-1.17; P for trend=0.71). TL was associated with increased risk of early menopause (HR = 1.17, 95% CI, 1.06-1.28). LIMITATIONS, REASONS FOR CAUTION Our study population is homogenous with respect to race and ethnicity. Additional evaluation of these relations in more diverse populations is important. WIDER IMPLICATIONS OF THE FINDINGS To our knowledge, this is the largest study examining the association of OC use and TL with early natural menopause to date. While TL was associated with a modest higher risk of early menopause, our findings do not support any material hazard or benefit for the use of OCs. STUDY FUNDING/COMPETING INTEREST(S) The study was sponsored by UO1CA176726 and R01HD078517 from the National Institutes of Health and Department of Health and Human Services. The work was supported by the Intramural Research Program of the Eunice Kennedy Shriver National Institute of Child Health and Human Development. The authors have no competing interests to report. TRIAL REGISTRATION NUMBER N/A

Diffusion-Weighted MR Imaging in the Evaluation of Normal Appearing White Matter in Patients with Tuberous Sclerosis

2003 ◽  
Vol 16 (2) ◽  
pp. 263-266
Author(s):  
F.G. Garaci ◽  
R. Floris ◽  
G. Manenti ◽  
L.M. Fantozzi ◽  
A. Bozzao
Keyword(s):  
White Matter ◽  
Mr Imaging ◽  
Tuberous Sclerosis ◽  
Centrum Semiovale ◽  
Normal Appearing White Matter ◽  
Diffusion Weighted ◽  
Adc Values ◽  
Mr Sequences ◽  
Supratentorial White Matter

The aim of the present study was to assess the presence of changes in diffusivity in the brains of patients with tuberous sclerosis (TS) in areas free from signal alterations on conventional MR sequences. Ten patients and controls were evaluated. ROI were placed on ADC maps in the white matter (frontal, parietal and centrum semiovale) excluding areas with signal alterations on FLAIR images. ADC values of supratentorial white matter turned out to be higher than controls (P < .0001). Our data indicate that TS is more widely diffused than expected in the brains of affected patients.

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