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Diagnostic performances of intravoxel incoherent motion and conventional diffusion-weighted imaging in the differential diagnosis of benign and malignant portal vein thrombus

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Purpose: To evaluate the diagnostic accuracy of intravoxel incoherent motion (IVIM) and diffusion-weighted imaging (DWI) parameters in the differential diagnosis of portal vein thrombus (PVT). Methodology: Thirty-five patients with PVT were enrolled in this retrospective study. Precontrast axial in-phase and out-of-phase T1-weighted (W) turbo field echo (TFE), axial and coronal T2-W single-shot turbo spin echo, IVIM with b values between 0 and 1300 s/mm2 and conventional DWI with b factors of 50, 400, and 800 s/mm2 with single-shot echo-planar imaging, and postcontrast dynamic T1-W volumetric interpolated breath-hold examination images obtained with 1.5 T MR unit were evaluated. For quantitative analysis of conventional DWI, an ADC map was reconstructed from conventional DWI using all b values. For quantitative evaluation of IVIM, the SI was calculated from each b value. A specific software program was applied to calculate D (true diffusion coefficient), D* (pseudodiffusion coefficient associated with blood flow), and f (perfusion fraction). The differentiation between benign and malignant PVT was based on the criteria outlined in the study by Catalano et al. (Radiology 254:154-162, 2010). Results: The ADC values of the malignant PVT were significantly lower than those of benign PVTs (p = 0.005). Malignant PVTs had a tendency to show higher f values in comparison with benign PVTs without statistical significance (p = 0.750). The best discriminative parameter was ADC values, which demonstrated a sensitivity of 80.0% and a specificity of 72.7% with cut-off value of 1.00 × 10-3 mm2/s. Conclusion: ADC values might be more superior tool than IVIM parameters in differentiation between malignant and benign PVT.
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Diagnostic performances of intravoxel
incoherent motion and conventional diffusion-
weighted imaging in the differential diagnosis
of benign and malignant portal vein thrombus
Emel Kaya Aumann ,
1,4
Sadik Server,
1
Bedriye Koyuncu Sokmen,
1
Aysegul Oz,
1
Esat Namal,
2
Nagihan Inan Gurcan,
1
Numan Cem Balci,
1
Yaman Tokat
3
1
Department of Radiology, Istanbul Bilim University Medical School, Esentepe, Istanbul, Turkey
2
Department of Medical Oncology, Istanbul Bilim University Medical School, Esentepe, Istanbul, Turkey
3
Department of General and Transplantation Surgery, Istanbul Bilim University Medical School, Esentepe, Istanbul, Turkey
4
Sisli Florence Nightingale Hospital Department of Radiology, Istanbul Bilim University, Abide-i Hurriyet Street, No:164, 34380
Istanbul, Turkey
Abstract
Purpose: To evaluate the diagnostic accuracy of intra-
voxel incoherent motion (IVIM) and diffusion-weighted
imaging (DWI) parameters in the differential diagnosis
of portal vein thrombus (PVT).
Methodology: Thirty-five patients with PVT were en-
rolled in this retrospective study. Precontrast axial in-
phase and out-of-phase T1-weighted (W) turbo field
echo (TFE), axial and coronal T2-W single-shot turbo
spin echo, IVIM with bvalues between 0 and 1300 s/mm
2
and conventional DWI with bfactors of 50, 400, and
800 s/mm
2
with single-shot echo-planar imaging, and
postcontrast dynamic T1-W volumetric interpolated
breath-hold examination images obtained with 1.5 T
MR unit were evaluated. For quantitative analysis of
conventional DWI, an ADC map was reconstructed
from conventional DWI using all bvalues. For quanti-
tative evaluation of IVIM, the SI was calculated from
each bvalue. A specific software program was applied to
calculate D(true diffusion coefficient), D* (pseudodiffu-
sion coefficient associated with blood flow), and f(per-
fusion fraction). The differentiation between benign and
malignant PVT was based on the criteria outlined in the
study by Catalano et al. (Radiology 254:154–162, 2010).
Results: The ADC values of the malignant PVT were
significantly lower than those of benign PVTs
(p= 0.005). Malignant PVTs had a tendency to show
higher fvalues in comparison with benign PVTs without
statistical significance (p= 0.750). The best discrimina-
tive parameter was ADC values, which demonstrated a
sensitivity of 80.0%and a specificity of 72.7%with cut-
off value of 1.00 910
-3
mm
2
/s.
Conclusion: ADC values might be more superior tool
than IVIM parameters in differentiation between malig-
nant and benign PVT.
Key words: Portal vein thrombus—Malignant
thrombus—Benign thrombus—IVIM—DWI
Portal vein thrombus (PVT) can present in a variety of
conditions including benign (chronic liver disease,
infection, hypercoagulability) or malignant (hepatocel-
lular carcinoma (HCC), cholangiocarcinoma, metas-
tases) diseases [1]. Benign PVT occurs in 4.5–26%of
patients with chronic liver disease. On the other hand,
malignant PVT is found in 6.5–44%of patients with
HCC. In addition, benign and malignant PVT can be
coexistent [24]. The presence of malignant PVT serves
as an important determinant of tumor staging, as well as
prognosis, and influences treatment selection [58]. As
the patient with malignant PVT is an absolute con-
traindication for liver transplantation, careful differential
diagnosis of PVT etiology is required for the selection of
optimal treatment. Therefore, the detection and accurate
differentiation of benign and malignant PVT are crucial
for patient treatment.
Correspondence to: Emel Kaya Aumann; email: dremelkaya@gmail.
com
ª
Springer Science+Business Media, LLC, part of
Springer Nature 2018
Published online: 7 February 2018
Abdominal
Radiology
Abdom Radiol (2018) 43:2270–2276
https://doi.org/10.1007/s00261-018-1467-6
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
... Su moleküllerinin farklı dokulardaki Brownian hareketi farklılığı temeline dayanan DAG kullanımı ile benign karaciğer lezyonlarının malign lezyonlardan ayrımının yapılabileceği bildirilmiştir (17)(18)(19)(20)(21)(22). Difüzyon ağırlıklı görüntülemenin malign ve benign PVT ayrımında tanıya katkı sağlayabileceği de bildirilmiştir (8,23 ...
... ADC haritasında (h) malign portal ven trombozunda (ok) ve hepatosellüler karsinomda difüzyon kısıtlanması izlenmiştir. olarak anlamlı düşük saptanmıştır(23). Çalışmalarda elde edilmiş farklı sonuçların nedeni tam olarak aydınlatılamamış olsa da Ahn ve ark.nın yaptığı çalışmada benign PVT olgularında saptanan düşük ADC değerlerinin trombozun evresine bağlı olabileceği ileri sürülmüştür(26).Damar çapının artışı malign PVT tanısı için bir görüntüleme bulgusu olarak bildirilmiştir(15,24). ...
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Giriş ve Amaç: Bu çalışmada malign ile benign portal ven trombozunun ayrımında 3 Tesla manyetik rezonans görüntülemede difüzyon ağırlıklı görüntülemenin rolünün araştırılması amaçlanmaktadır. Gereç ve Yöntem: Ocak 2011 - Aralık 2016 tarihleri arasında 3 Tesla manyetik rezonans görüntüleme ünitesinde elde edilmiş abdomen manyetik rezonans görüntüleme incelemeleri portal ven trombozu mevcut olguları tespit etmek için retrospektif olarak değerlendirildi. Kontrastsız görüntüler ile karşılaştırıldığında arteriyel faz kontrastlı görüntülerde ≥%15 kontrast tutulumu gösteren portal ven trombozu malign olarak kabul edildi. Tromboz saptanan portal venin çapı ölçülüp difüzyon ağırlıklı görüntülerde portal ven trombozu sinyal intensitesi kaydedildi. İki bağımsız gözlemci tarafından malign ve benign portal ven trombozlarının görünür difüzyon katsayısı değerleri ölçüldü. Bulgular: Malign portal ven trombozu bulgusu olan 23 olgu [19 erkek, 4 kadın; ortanca yaş 63 (52-83)] ve benign portal ven trombozu bulgusu olan 14 olgu [5 erkek, 9 kadın; ortanca yaş 65 (47-82)] tespit edildi. Difüzyon ağırlıklı görüntülerde malign ile benign portal ven trombozu sinyal intensitesi yönünden istatistiksel olarak anlamlı fark saptandı (p
... In line with our finding, a study found that ADC revealed 80% sensitivity and 72.7% specificity with a cutoff value of 1.00 × 10−3 mm2/s. 13 Also, another ROC curve in the Study revealed the cutoff value of ADC (⩽1) discriminated malignant from benign PVT with 100% sensitivity and 82.5% specificity. 14 Nevertheless, there is a study that stated an ADC value that discriminates among benign and malignant PVTs with a sensitivity of 22.2% due to the large range and significant overlap of ADC. ...
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