Editorial for "Blood-Brain Barrier Permeability to Water Measured Using Multiple Echo Time Arterial Spin Labeling MRI in the Aging Human Brain"

Level of Evidence

5

Technical Efficacy Stage

2

Evaluation of left renal vein entrapment using multidetector computed tomography

BACKGROUND

Nutcracker syndrome, also called left renal vein entrapment syndrome, is a cause of non-glomerular hematuria with difficulties in diagnosis. Multidetector computed tomography (MDCT) is a powerful tool to prevent unnecessary diagnostic procedures.

PURPOSE

To retrospectively determine the prevalence of nutcracker phenomenon and nutcracker syndrome seen in MDCT in consecutive patients.

MATERIAL AND METHODS

The institutional review board approved the study and waived the requirement for informed consent. Abdominal contrast-enhanced MDCT scans were reviewed from 1000 consecutive patients. MDCT scan assessment included renal vein diameter measurements and evaluation for the presence of anterior or posterior left renal vein entrapment. Electronic medical records and urine analysis reports of patients with left renal vein entrapment were reviewed. Student's t test was used to assess differences in renal vein diameter in patients with left renal vein entrapment.

RESULTS

Left renal vein entrapment was observed in 10.9% (109), retro-aortic left renal vein in 6.5% (65), entrapment of left renal vein between superior mesenteric artery and aorta in 4.1% (41), and circumaortic left renal vein in 0.3% (3) of patients. Mean diameters of right (8.8 ± 1.9 mm) and unentrapped left (8.9 ± 1.8 mm) renal veins were not significantly different (P = 0.1). The mean diameter of anterior entrapped left renal veins (10.3 ± 2 mm) was significantly greater (P = 0.04) than contralateral renal veins (8.6 ± 2.1 mm) in their widest portion. In 8.8% of patients with the left renal vein entrapment, urine analysis showed isomorphic hematuria or proteinuria with no other known cause. Varicocele and pelvic congestion were seen in 5.5% of patients with the left renal vein entrapment.

CONCLUSION

Left renal vein entrapment is not a rare entity and renal nutcracker phenomenon might be underdiagnosed.

Diffusion-weighted MRI of fatty liver

PURPOSE

To investigate the effect of fat infiltration on the apparent diffusion coefficient (ADC) of liver, and assess the relationship between ADC and hepatic fat fraction (HFF).

MATERIALS AND METHODS

MRI scans of 120 consecutive patients were included in this retrospective study. Of these, 42 patients were included in the fatty liver group and 78 in the control group. ADC values were measured from a pair of diffusion-weighted (DW) images (b = 0 mm(2) /s and 1000 mm(2) /s). HFFs were measured using T1W GRE dual-echo images. The difference between the ADCs of the two groups was assessed with the t-test. The relationship between HFF and ADC was determined using linear regression analysis and the Pearson correlation coefficient (r).

RESULTS

Mean HFFs were 0.85 ± 2.86 and 13.67 ± 8.62 in the control and fatty liver groups, respectively. The mean ADC of fatty liver group 1.20 ± 0.22 × 10(-3) mm(2) /s was significantly lower than that of the control group 1.32 ± 0.23 × 10(-3) mm(2) /s (P = 0.02). Linear regression analysis revealed an inverse relationship between ADC and HFF (r = -0.39, P < 0.0001).

CONCLUSION

ADC significantly decreases in patients with >5% HFF, and ADC and HFF exhibit an inverse relationship.

Hamartoma of the breast

Breast hamartoma is a rare benign tumour that leads to unilateral breast enlargement without a palpable localized mass lesion. Histologically, a hamartoma consists of varying amounts of adipose, gland, fibre and smooth muscle tissue. The characteristic mammographic appearance of hamartoma of breast has distinct mammographic features with circumscription and fat and soft-tissue density surrounded by a thin radiopaque capsule or pseudocapsule. Ultrasonographic findings include a well-defined mass lesion consisting of echogenic and sonolucent areas. We present histopathological and radiological findings of a 42-year-old female patient with breast hamartoma who has no complaint.