Single photon emission computed tomography/computed tomography of
the skull in malignant otitis externa
Dhritiman Chakraborty, MD
, Anish Bhattacharya, DNB
Koramadai Karuppusamy Kamaleshwaran, MD
, Kanhaiyalal Agrawal, MBBS
Ashok Kumar Gupta, MS
, Bhagwant Rai Mittal, MD
Department of Nuclear Medicine, PGIMER, Chandigarh, India
Department of Otorhinolaryngology, PGIMER, Chandigarh, India
Received 15 March 2011
Abstract Malignant otitis externa is a severe, rare infective condition of the external auditory canal and
skull base. The diagnosis is generally made from a range of clinical, laboratory, and imaging
findings. Technetium 99m methylene diphosphonate bone scintigraphy is known to detect
osteomyelitis earlier than computed tomography. The authors present a patient with bilateral
malignant otitis externa where the extent of skull base involvement was determined on 3-phase bone
scintigraphy with single photon emission computed tomography/computed tomography.
© 2012 Elsevier Inc. All rights reserved.
Malignant otitis externa (MOE) is a severe, rare infection of
the external auditory canal and skull base . The diagnosis is
generally made from a range of clinical, laboratory, and
imaging findings. Characteristic computed tomography (CT)
findings of bone erosion and decreased skull base density may
be discovered late in the course of the disease . Scintigraphy
is a sensitive technique for early detection of bony infections.
A combination of CT and tomographic scintigraphy may
provide more specific information in identifying the extent of
skull base osteomyelitis in such cases.
2. Case report
A 69-year-old diabetic man presented with vertigo, pain,
and discharge from both ears and left facial palsy.
Granulation tissue was found in the external auditory
canal of both ears. Triphasic bone scintigraphy of the skull
was performed under a dual-head γ camera (Infinia
Hawkeye; GE, Milwaukee, WI) after intravenous injection
of 740 MBq (20 mCi) of technetium Tc 99m methylene
diphosphonate (MDP). Initial dynamic images were
acquired at the rate of 2 seconds per frame, followed by
a static image, comprising the soft tissue (blood pool)
phase, 1 minute after injection. Delayed static images were
then acquired after 3 hours, followed by single photon
emission computed tomography/CT (SPECT/CT) of the
skull. Increased perfusion was seen in both temporal
regions in the initial dynamic images (not shown here),
followed by increased uptake of the tracer in the blood pool
(Fig. 1A) and delayed images in the same region (Fig. 1B).
Hybrid SPECT/CT imaging (Fig. 1C and D) localized the
abnormal tracer concentration to both mastoid bones with
extension into the left petrous temporal and right zygomatic
bones (arrows) and locally destructive changes. Ear swab
culture showed growth of Pseudomonas aeruginosa,
sensitive to amikacin and ceftazidime. Histopathology of
the granulation tissue revealed features of acute inflamma-
tion with no evidence of malignancy. Antibiotic treatment
was continued, with good clinical response.
Available online at www.sciencedirect.com
American Journal of Otolaryngology–Head and Neck Medicine and Surgery 33 (2012) 128 – 129
Disclosure of funding: No separate funding was provided for this study.
Conflicts of interest: None of the authors have any conflict of interest.
Corresponding author. Department of Nuclear Medicine, PGIMER,
Chandigarh, 160012, India. Tel: +91 172 2756726(O), +91 172 2722003
(R), +91 9872486816(M); fax: +91 172 2744401.
E-mail address: email@example.com (A. Bhattacharya).
0196-0709/$ – see front matter © 2012 Elsevier Inc. All rights reserved.