Novel use of gamma correction for precise (99m)Tc-HDP pinhole bone scan diagnosis and classification of knee occult fractures.
OBJECTIVE
The aim of this study was to introduce gamma correction pinhole bone scan (GCPBS) to depict specific signs of knee occult fractures (OF) on (99m)Tc-hydroxydiphosphonate (HDP) scan.


METHODS
Thirty-six cases of six different types of knee OF in 27 consecutive patients (male = 20, female = 7, and age = 18-86 years) were enrolled. The diagnosis was made on the basis of a history of acute or subacute knee trauma, local pain, tenderness, cutaneous injury, negative conventional radiography, and positive magnetic resonance imaging (MRI). Because of the impracticability of histological verification of individual OF, MRI was utilized as a gold standard of diagnosis and classification. All patients had (99m)Tc-HDP bone scanning and supplementary GCPBS. GCPBS signs were correlated and compared with those of MRI. The efficacy of gamma correction of ordinary parallel collimator and pinhole collimator scans were collated.


RESULTS
Gamma correction pinhole bone scan depicted the signs characteristic of six different types of OF. They were well defined stuffed globular tracer uptake in geographic I fractures (n = 9), block-like uptake in geographic II fractures (n = 7), simple or branching linear uptake in linear cancellous fractures (n = 4), compression in impacted fractures (n = 2), stippled-serpentine uptake in reticular fractures (n = 11), and irregular subcortical uptake in osteochondral fractures (n = 3). All fractures were equally well or more distinctly depicted on GCPBS than on MRI except geographic II fracture, the details of which were not appreciated on GCPBS. Parallel collimator scan also yielded to gamma correction, but the results were inferior to those of the pinhole scan.


CONCLUSIONS
Gamma correction pinhole bone scan can depict the specific diagnostic signs in six different types of knee occult fractures. The specific diagnostic capability along with the lower cost and wider global availability of bone scanning would make GCPBS an effective alternative.
Bahk
Yong-Whee
YW
Department of Nuclear Medicine, Sung Ae General Hospital, Seoul, Korea.
Jeon
Ho-Seung
HS
Kim
Jang Min
JM
Park
Jung Mee
JM
Chung
Yong-An
YA
Kim
E Edmund
EE
Kim
Sung-Hoon
SH
Chung
Soo-Kyo
SK
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004164:Diphosphonates; D005260:Female; D005596:Fractures, Closed / Q000145:classification / Q000175:diagnosis; D006801:Humans; D007719:Knee Joint; D008297:Male; D008875:Middle Aged; D015609:Organotechnetium Compounds; D012189:Retrospective Studies
D004164:Diphosphonates; D015609:Organotechnetium Compounds; C060491:technetium Tc 99m hydroxydiphosphonate
J Trauma. 1981 Jul;21(7):564-9
6265653
Radiology. 1989 Mar;170(3 Pt 1):823-9
2916038
Skeletal Radiol. 1998 Dec;27(12):683-7
9921930
Am J Sports Med. 1998 May-Jun;26(3):409-14
9617404
Radiology. 1989 Jan;170(1 Pt 1):113-6
2909083
Radiology. 1991 Jan;178(1):271-6
1984319
J Bone Joint Surg Am. 1993 Mar;75(3):395-401
8444918
AJR Am J Roentgenol. 2008 Jan;190(1):10-6
18094287
Radiographics. 2008 Oct;28(6):1771-84
18936035
Acta Orthop Scand. 1998 Jun;69(3):291-4
9703406
Clin Imaging. 2000 Nov-Dec;24(6):371-80
11368941
Clin Radiol. 2005 Jun;60(6):627-36
16038689