Diffusion-Weighted Imaging in the Oral and Maxillofacial Region: Usefulness of Apparent Diffusion Coefficient Maps and Maximum Intensity Projection for Characterization of Normal Structures and Lesions

Abstract

SummaryBackgroundThe aim of this study was to investigate diffusion-weighted imaging (DWI) in the oral and maxillofacial region, with a special focus on the usefulness of apparent diffusion coefficient (ADC) maps and maximum intensity projection (MIP) for characterization of normal structures and lesions.Material/MethodsThirty-five patients who underwent magnetic resonance imaging (MRI) for diagnosis of oral and maxillofacial lesions were included in this prospective study. DWI was performed on a 1.5 T unit, with b factor of 0 and 800 s/mm2; moreover, ADC maps were generated. ADC values were measured for normal structures, odontogenic infections, squamous cell carcinomas (SCC), and hemangiomas.ResultsAs regards the normal structures, the mean ADC value of the cerebrospinal fluid (3.65±0.60×10–3 mm2/s) in the upper neck area was higher than that of the spinal cord (0.74±0.15×10–3 mm2/s, P=0.000), lymph nodes (0.87±0.17×10–3 mm2/s, P=0.000), and Waldeyer’s ring (0.92±0.29×10–3 mm2/s, P=0.000). The mean ADC value of hemangiomas (1.52±0.31×10–3 mm2/s) was higher than that of odontogenic infections (0.85±0.36×10–3 mm2/s, P=0.034) and SCC (1.38±0.22×10–3 mm2/s, P=0.840). Furthermore, MIP (DWI) showed the normal structures and lesions in the oral and maxillofacial region in an improved way.ConclusionsDWI, ADC maps, and MIP can be used to characterize and differentiate normal structures and lesions in the oral and maxillofacial region.

Tc-99m hydroxymethylene diphosphonate scintigraphy, computed tomography, and magnetic resonance imaging of osteonecrosis in the mandible: Osteoradionecrosis versus medication-related osteonecrosis of the jaw

“…Bonello et al20 showed that DWI could provide information on microstructural tumor characteristics. Previous studies have reported that DWI and ADC maps were useful for the differential diagnosis of oral and maxillofacial lesions 1516. In our study, all cases (ORN and MRONJ) showed high signal intensity on DWI, and low signal intensity on ADC maps.…”

“…The images were acquired using a 16-MDCT apparatus (Aquilion TSX-101A; Canon Medical Systems, Otawara, Japan), a 1.5-T MR imaging system (EXCELART Vantage MRT-2003; Canon Medical Systems, Otawara, Japan), and a SNC-5100R scintigraphy apparatus (Shimadzu, Kyoto, Japan) with Tc-99m HMDP (Clear Bone Injection; Nihon Medi-Physics, Tokyo, Japan), following our institutional protocol 8141516…”

Diffusion‐weighted magnetic resonance imaging in the palatal tumors: Usefulness of apparent diffusion coefficient value for characterization of benign and malignant tumors

“…We used regions of interest (ROI) to calculate the ADC values on ADC maps. We placed five ROIs with similar sizes within the lesions to obtain a mean ADC value (Figure 1), following our institutional protocol 7‐9 , and ADC value were automatically measured.…”

“…DWI with apparent diffusion coefficient (ADC) maps, which provides a quantitative index of water diffusivity for each voxel that allows the visualization of the microscopic motion of water molecules within tissues, can facilitate data acquisition and processing steps without the use of ionizing radiation or contrast agents 6 . Therefore, DWI has been considered a useful imaging on diagnostic ability of ADC maps in oral and maxillofacial lesions 7‐9 . Furthermore, some studies have reported the application of DWI with the calculation of ADC in the differential diagnosis of lesions in the major salivary glands 10 and floor of the mouth 11 .…”

Techniques, Tricks, and Stratagems of Oral Cavity Computed Tomography and Magnetic Resonance Imaging

“…Differentiate oral cavity abscesses from cystic/necrotic tumours. An abscess shows high signal on DWI trace images and low values on ADC maps (0.7-0.85 × 10 −3 mm 2 /s) (Figure 4), whereas a cystic/necrotic tumour usually has high values on ADC maps (>2.0 × 10 −3 mm 2 /s) [30][31][32];…”