In Vivo Assessment of Neurodegeneration in Type C Niemann-Pick Disease by IDEAL-IQ

Peritumoral Fat Content Identified Using Iterative Decomposition of Water and Fat with Echo Asymmetry and Least-squares Estimation (IDEAL) Correlates with Breast Cancer Prognosis

PURPOSE

Adipocytes around aggressive breast cancer (BC) are less lipid different from naive adipocytes (cancer-associated adipocytes, CAAs), and peritumoral edema caused by the release of cytokines from CAAs can conduce to decrease the peritumoral fat proportion. The purpose of this study was to correlate peritumoral fat content identified by using iterative decomposition of water and fat with echo asymmetry and least-squares estimation (IDEAL) with lymph node metastasis (LNM) and recurrence-free survival (RFS) in BC patients and to compare with T2-weighted (T2WI) and diffusion-weighted images (DWI) analyses.

METHODS

This retrospective study consisted of 85 patients who were diagnosed with invasive carcinoma of breast and underwent breast MRI, including IDEAL before surgery. The scan time of fat fraction (FF) map imaging using IDEAL was 33s. Four regions of interest (ROIs), which are 5 mm from the tumor edge, and one ROI in the mammary fat of the healthy side were set on the FF map. Then average peritumoral FF values (TFF), average FF values on the healthy side (HFF), and peritumoral fat ratio (PTFR, which is defined as TFF/HFF) were calculated. Tumor apparent diffusion coefficient (ADC) values were measured on ADC map obtained by DWI. Peritumoral edema was classified into three grades based on the degree of signal intensity around the tumor on T2WI (T2 edema).

RESULTS

The results of stepwise logistic regression analysis for four variables (TFF, PTFR, T2 edema, and ADC value) indicated that TFF and T2 edema were significant factors of LNM (P < 0.01). RFS was significantly associated with TFF (P = 0.016), and 47 of 49 (95.9%) patients with TFF more than 85.5% were alive without recurrence.

CONCLUSION

Peritumoral fat content identified by using IDEAL is associated with LNM and RFS and may therefore be a useful prognostic biomarker for BC.

Accuracy and applicability of dual-energy computed tomography in quantifying vertebral bone marrow adipose tissue compared with magnetic resonance imaging

Objectives

To evaluate the accuracy of dual-energy computed tomography (DECT) in quantifying bone marrow adipose tissue (BMAT) and its applicability in the study of osteoporosis (OP).

Methods

A total of 83 patients with low back pain (59.77 ± 7.46 years, 30 males) were enrolled. All patients underwent lumbar DECT and magnetic resonance imaging (MRI) scanning within 48 h, and the vertebral fat fraction (FF) was quantitatively measured, recorded as DECT-FF and MRI-FF. A standard quantitative computed tomography (QCT) phantom was positioned under the waist during DECT procedure to realize the quantization of bone mineral density (BMD). The intraclass correlation coefficient (ICC) and Bland–Altman method was used to evaluate the agreement between DECT-FF and MRI-FF. The Pearson test was used to study the correlation between DECT-FF, MRI-FF, and BMD. With BMD as a gold standard, the diagnostic efficacy of DECT-FF and MRI-FF in different OP degrees was compared by receiver operating characteristic (ROC) curve and DeLong test.

Results

The values of DECT-FF and MRI-FF agreed well (ICC = 0.918). DECT-FF and MRI-FF correlated with BMD, with r values of −0.660 and −0.669, respectively (p < 0.05). In the diagnosis of OP and osteopenia, the areas under curve (AUC) of DECT-FF was, respectively, 0.791 and 0.710, and that of MRI-FF was 0.807 and 0.708, and there was no significant difference between AUCs of two FF values (with Z values of 0.503 and 0.066, all p > 0.05).

Conclusion

DECT can accurately quantify the BMAT of vertebrae and has the same applicability as MRI in the study of OP.

Targeting neurological abnormalities in lysosomal storage diseases

Central nervous system (CNS) abnormalities and corresponding neurological and psychiatric symptoms are frequently observed in lysosomal storage disorders (LSDs). The genetic background of individual LSDs is indeed unique to each illness. However, resulting defective lysosomal function within the CNS can transition normal cellular processes (i.e., autophagy) into aberrant mechanisms, facilitating overlapping downstream consequences including neurocircuitry dysfunction, neurodegeneration as well as sensory, motor, cognitive, and psychological symptoms. Here, the neurological and biobehavioral phenotypes of major classes of LSDs are discussed alongside therapeutic strategies in development that aim to tackle neuropathology among other disease elements. Finally, focused ultrasound blood-brain barrier opening is proposed to enhance therapeutic delivery thereby overcoming the key hurdle of central distribution of disease modifying therapies in LSDs.

Quantification of penile fat infiltration using the mDIXON Quant sequence: a pilot study on the correlation with penis hardness and erectile dysfunction

OBJECTIVE

The purpose of this study was to determine fat/water signal ratios using the mDIXON Quant sequence, quantitatively assess fat infiltration in the penis, and explore its possible relationship with penile hardness and erectile dysfunction.

METHODS

Routine pelvic MRI with the mDIXON Quant sequence was performed in 62 subjects, including 22 people in the normal group, 20 people in the normal erectile hardness group, and 20 people in the erectile dysfunction (ED) group. The fat/water signal ratio in the penis was measured using the mDIXON Quant sequence. Shear wave elastography was used to evaluate the hardness of the corpus cavernosa of the penis.

RESULTS

The fat/water signal ratio of the corpus spongiosum was significantly lower than that of the corpus cavernosa in the normal group (p = 0.03) and ED group (p < 0.01). There was no significant difference in the fat/water signal ratios between the normal group and the normal erectile hardness group. Fat infiltration was significantly lower, and erectile hardness was significantly higher in the normal erectile hardness group than in the ED group, and the fat infiltration in the left and right corpus cavernosa was inversely proportional to the erectile hardness of the penis.

CONCLUSION

This study suggests that mDIXON Quant can be used as a non-invasive, quantitative, and objective method for evaluating penile fat infiltration. This method could help diagnose penile fat infiltration in patients with erectile dysfunction and varying body mass indexes. Our results could also allow for a more accurate diagnosis and monitoring of erectile hardness function by quantitatively measuring penile fat infiltration.

ADVANCES IN KNOWLEDGE

(1) The proton density fat fraction technology is a new tool for the objective, quantitative and non-invasive evaluation of penile fat infiltration. (2) The quantitative measurement of fat infiltration in the corpora cavernosa might help diagnose and monitor penile erection hardness and its function more accurately.

Peritumoral Fat Content Correlates with Histological Prognostic Factors in Breast Carcinoma: A Study Using Iterative Decomposition of Water and Fat with Echo Asymmetry and Least-Squares Estimation (IDEAL)

Purpose:

To correlate peritumoral fat content using iterative decomposition of water and fat with echo asymmetry and least-squares estimation (IDEAL) with histologic prognostic factors in breast carcinoma.

Methods:

This study consisted of 100 patients who were diagnosed with invasive carcinoma of breast and underwent breast MRI including IDEAL before surgery. The scan time of IDEAL fat fraction (FF) map imaging was 33 s. Four regions of interests (ROIs), which are a distance of 5 mm from the tumor edge, and one ROI in the mammary fat of the healthy side were set on the FF map. Then average peritumoral FF values (FFt), average FF values in the healthy side (FFh), and peritumoral fat ratio (pTFR: defined as FFt/FFh) were calculated. Histologically, the presence of lymph node metastasis and the MIB-1 index were evaluated.

Results:

FFt and pTFR for breast carcinoma with lymph node metastasis (79.27 ± 10.36 and 0.897 ± 0.078) were significantly lower than those without (86.23 ± 4.53 and 0.945 ± 0.032) (P < 0.001 and P = 0.005). Spearman rank correlation suggested that the FFt correlated with the MIB-1 index (r = −340, P = 0.001).

Conclusion:

Quantification of peritumoral fat using IDEAL-iron quantification is associated with the histologic prognostic factors, and may be a practical tool for therapeutic strategy of breast carcinoma.

Quantification of testicular fat deposition in the evaluation of middle-aged overweight male infertility

OBJECTIVES

To measure the testicular volume and testicular fat deposition of middle-aged overweight men and to assess the utility of testicular fat deposition and testicular volume in determining and monitoring testicular infertility.

MATERIALS AND METHODS

Pelvic MRI with thin slice T2WI, T1WI and mDIXON Quant was performed on 30 middle-aged overweight patients in the treatment group and 30 middle-aged overweight men in the control group. Testicular volume and testicular fat deposition were measured separately based on thin slice T2WI and the fat fraction (FF) map of mDIXON Quant, and the testicular fat deposition observed with T1WI was used as a reference for qualitative diagnosis. Testicular volume and testicular fat deposition in middle-aged overweight individuals were compared using a t test with Bonferroni correction and receiver operating characteristic (ROC) curve.

RESULTS

The testicular volumes (10.6-17.9 cm³) of individuals in the treatment group were smaller than those (12.6-19.0 cm³) of individuals in the control group (p < 0.05), and the average FF value (2.2-4.6%) of the testes in the treatment group was higher than that (1.5-3.1%) in the control group (p < 0.05). The ROC analysis showed that the area under the curve (AUC) of testicular fat deposition (0.899) was higher than that of testicular volume (0.777), and biopsy and sperm count were used as references to diagnose infertility. The diagnostic sensitivity (90.00%) of testicular fat deposition of the mDIXON Quant sequence was higher than that (50.00%) of the T1W sequence (p < 0.05). Testicular fat deposition was decreased after 6 months of active treatment with exercise weight loss and drug treatment, and no significant change in testicular volume was observed 6 months later.

CONCLUSION

The findings suggest that the proton density fat fraction (mDIXON Quant sequence in this study) approach is a novel tool for the quantitative and objective evaluation of testicular fat deposition. Testicular fat deposition measurement is more specific than testicular volume measurement in the diagnosis of male infertility, and the mDIXON Quant is more sensitive than T1WI in the diagnosis of testicular fat deposition. Furthermore, our findings may facilitate a more accurate diagnosis and monitoring of testicular infertility, therapeutic effect, and prognosis by measuring testicular fat deposition.

Quantification of fat deposition in the testis and epididymis using mDIXON Quant sequence: correlation with age and ejaculation

PURPOSE

The objective of this study was to quantitatively assess fat deposition in the testis and epididymis by measuring the fat/water signal ratios with mDIXON Quant and to investigate its correlation with age and ejaculation.

MATERIALS AND METHODS

Routine pelvic magnetic resonance imaging and mDIXON Quant were performed on 120 subjects. The fat/water signal ratios of the testis and epididymis were measured based on the fat/water signal intensity on mDIXON Quant.

RESULTS

The fat/water signal ratio values of the testis and epididymis in the early adulthood group (0.952-3.550%, p < 0.05, and 5.182-12.725%, p < 0.05, respectively) were significantly higher than those in the late childhood group (0.611-2.198% and 1.310-4.520%) and in the youth group (0.659-2.360% and 1.568-4.469%), and they were lower than those in the middle adulthood group (1.538-4.249%, p < 0.05, and 5.830-19.002%, p < 0.05). The fat deposition decreased in the testis of the youth group, who ejaculated more than ten times per month (0.750-2.022%, p < 0.05), and the fat/water signal ratios of the epididymis decreased in one subject in the early adulthood group who had three ejaculations within 12 h.

CONCLUSION

The findings of this study suggest that mDIXON Quant may be useful as a noninvasive, quantitative, and objective method for evaluating the fat deposition of the testis and epididymis. This method can provide guidance for fat deposition in the testis and epididymis in different age groups with varying ejaculation experiences. Additionally, our findings may facilitate more accurate diagnosis and monitoring of the reproductive function of the testis and epididymis by quantitatively measuring their fat deposition with age.