Purpose
We compared shear wave velocity measurement (SWV: acquired as a part of acoustic radiation force impulse elastography) with apparent diffusion coefficient (ADC) acquired from MRI exam to assess its capability to differentiate between benign and metastatic lymph nodes,
and to estimate the histological background reflected in SWV.
Background:
Ultrasonography (US) and MRI are both often used to evaluate enlarged cervical lymph nodes to diagnose metastasis; however,
the former alone is insufficient both in sensitivity and specificity [1,2],
while the latter is time-consuming,
costly,
and labor-intensive,...
Methods and Materials
Patients:
Clinical databases were retrospectively searched for patients who underwent both SWV measurement and MRI within a 90-day interval to investigate their cervical lymph nodes with the suspicion of metastasis.
Patients with lymph nodes not matching clearly between the two modalities were excluded.
Finally,
6 patients with lymph nodes considered metastatic (pathologically and/or clinically: metastasis group) and 17 patients without obvious metastatic nodes (pathologically,
or at least 6 months of clinical observation: control group) met the criteria.
The largest node from each patient was selected...
Results
SWV was higher in the metastasis group with significant difference (P<0.01).
The average and median ADC values were lower in the metastasis group with significant difference (p=0.024 and 0.036,
respectively; Table 1,
Figure 3).
To note,
the significance of the difference was stronger in SWV compared to ADC (average,
median).
On the other hand,
the difference in SD of ADC was not significant between the groups (Table 1,
Figure 4).
The correlations were not significant between SWV and the average or median of ADC in...
Conclusion
SWV may be useful for diagnosing metastatic nodes.
It bears comparison with ADC,
and seems even superior to it.
Histologic homogeneity may be one of the reflected factors in SWV.
Discussion:
The difference in SWV between the control and metastasis groups was significant.
The significance was greater compared to any of the parameters of ADC.
This may suggest that SWV equals,
or may even be superior to ADC in the diagnosis of lymph node metastasis.
In addition,
SWV was not significantly correlated with the average...
References
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van den Brekel MW,
Castelijns JA,
Snow GB (1998) The size of lymph nodes in the neck on sonograms as a radiologic criterion for metastasis: how reliable is it? AJNR Am J Neuroradiol 19: 695-700.
3.
Zhang F,
Zhu L,
Huang X,
Niu G,
Chen X (2013) Differentiation of Reactive and Tumor Metastatic Lymph Nodes with Diffusion-weighted and SPIO-Enhanced MRI.
Mol Imaging Biol 15: 40-47.
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Miyaji K,
Furuse A,...