The Efficacy of Color-Mapped Diffusion-Weighted Images Combined With CT in the Diagnosis and Treatment of Cholesteatoma Using Transcanal Endoscopic Ear Surgery.
OBJECTIVE
To assess the efficacy of a color-mapped diffusion-weighted image combined with a computed tomography scan (CMDWI-CT) in preoperatively evaluating the anatomical location of cholesteatomas and determining whether a patient is indicated for transcanal endoscopic ear surgery (TEES) to reduce intraoperative switching to microscopic ear surgery (MES).


METHODS
Prospective case study.


METHODS
A single university hospital.


METHODS
Fifty-five patients scheduled for middle ear cholesteatoma surgery.


METHODS
The CMDWI-CT is produced in a multistep process. A color-mapped fusion image (CMFI) is created by performing MR cisternography on a 1-mm thin-slice nonecho planar diffusion-weighted imaging (non-EPI DWI) and then by performing color mapping on the resulting image to enhance cholesteatoma visualization. False positives are reduced by taking a T1-weighted image (T1WI), whereas false negatives are further reduced by preoperative endoscopic examination. As cholesteatomas are difficult to locate on a CMFI in the temporal bone region, we stripped out the MR cisternography data from the CMFI and then fused the CMFI to the initial computer tomography (CT) scan to create a CMDWI-CT. This CMDWI-CT better clarifies the cholesteatoma position within temporal bone.


METHODS
CMDWI-CT preoperative findings were compared with intraoperative findings. The positive predictive value and negative predictive value were also evaluated depending on the cholesteatoma location.


RESULTS
CMDWI-CT facilitated accurate detection of the cholesteatoma anatomical location in the temporal bone region which was reflected in positive predictive and negative predictive values of over 90% for all areas of the middle ear.


CONCLUSIONS
CMDWI-CT is a reliable diagnostic modality for evaluating the anatomical location of cholesteatomas that seem as high-signal regions on a CMFI and for determining whether TEES is indicated for treatment in such patients.
*Department of Otolaryngology, Head and Neck Surgery †Department of Diagnostic Radiology, Yamagata University Faculty of Medicine, Yamagata, Japan.
Tomoo
T
Watanabe
Tsukasa
T
Ito
Takatoshi
T
Furukawa
Kazunori
K
Futai
Toshinori
T
Kubota
Masafumi
M
Kanoto
Yuuki
Y
Toyoguchi
Takaaki
T
Hosoya
Seiji
S
Kakehata
D000328:Adult; D018424:Cholesteatoma, Middle Ear / Q000175:diagnosis* / Q000601:surgery*; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods; D004432:Ear, Middle / Q000601:surgery; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging / Q000379:methods*; D057605:Natural Orifice Endoscopic Surgery / Q000379:methods; D013506:Otologic Surgical Procedures / Q000379:methods; D013517:Otorhinolaryngologic Surgical Procedures / Q000379:methods*; D011446:Prospective Studies; D013701:Temporal Bone / Q000601:surgery; D013702:Temporal Lobe; D014057:Tomography, X-Ray Computed / Q000379:methods