From the Guidelines
The lesion's increased visibility with a slice thickness of 2.50mm does not confirm growth, as changes in slice thickness can significantly impact lesion visibility and apparent size. When assessing the growth of kidney masses, it is essential to use the same imaging modality to ensure accurate comparisons, as recommended by the ERKNet working group for autosomal dominant structural kidney disorders and the ERA Genes & Kidney working group 1. The provided evidence highlights the importance of consistent imaging parameters, as differences in slice thickness can affect the visibility and apparent size of lesions. In this case, the lesion's decreased visibility with slice thicknesses of 3.75mm and 3.00mm, but increased visibility with a slice thickness of 2.50mm, is likely due to the technical changes rather than actual growth. Some key points to consider when evaluating lesion growth include:
- Using the same imaging modality for consistent comparisons
- Considering the impact of slice thickness on lesion visibility and apparent size
- Possibly using volumetric measurements rather than simple diameter measurements for more accurate assessments
- Accounting for technical differences when comparing images across scans. Given these considerations, a radiologist should compare the images, taking into account the technical differences, to determine if the lesion has actually grown 1.
From the Research
Lesion Visibility and Slice Thickness
- The visibility of a lesion in the fat anterior to the psoas muscle, caudal to the lower pole of the kidney, increased with a slice thickness of 2.50mm, but decreased with slice thicknesses of 3.75mm and 3.00mm 2, 3, 4.
- This suggests that the lesion may be small and may not be easily visible with thicker slice thicknesses.
Lesion Growth and Confirmation
- There is no direct evidence to confirm that the lesion is growing or malignant based on the provided information 5, 6.
- The studies suggest that imaging-guided biopsies and texture analysis can be used to diagnose and distinguish between malignant and benign lesions, but the results are not always conclusive 3, 4, 5.
- The visibility of the lesion with different slice thicknesses may not be a reliable indicator of growth or malignancy.
Diagnostic Techniques
- Imaging-guided core needle biopsy is a safe and effective procedure for diagnosing bone and soft tissue tumors, with a diagnostic accuracy of 90% 4.
- Diffusion-weighted magnetic resonance imaging and apparent diffusion coefficient measurement can be used to assist in biopsy planning and distinguish between malignant and benign lesions 3.
- Texture analysis of CT images can be used to distinguish between metastatic and benign lesions, but the results are not always conclusive 5.