Is computer-aided interpretation of 99Tcm-HMPAO leukocyte scans better than the naked eye?
In order to compare visual interpretation of inflammation detected by leukocyte scintigraphy with that of different computer-aided quantification methods, 34 patients (25 with ulcerative colitis and 9 with endoscopically verified non-inflamed colonic mucosa), were investigated using 99Tcm-hexamethylpropyleneamine oxime (99Tcm-HMPAO) leukocyte scintigraphy and colonoscopy with biopsies. Scintigrams were obtained 45 min and 4 h after the injection of labelled cells. Computer-generated grading of seven colon segments using four different methods was performed on each scintigram for each patient. The same segments were graded independently using a 4-point visual scale. Endoscopic and histological inflammation were scored on 4-point scales. At 45 min, a positive correlation was found between endoscopic and scan gradings in individual colon segments when using visual grading and three of the four computer-aided methods (Spearman's rs = 0.30-0.64, P < 0.001). Histological grading correlated with visual grading and with two of the four computer-aided methods at 45 min (rs = 0.42-0.54, P < 0.001). At 4 h, all grading methods correlated positively with both endoscopic and histological assessment. The correlation coefficients were, in all but one instance, highest for the visual grading. As an inter-observer comparison to assess agreement between the visual gradings of two nuclear physicians, 14 additional patients (9 ulcerative colitis, 5 infectious enterocolitis) underwent leukocyte scintigraphy. Agreement assessed using kappa statistics was 0.54 at 45 min (P < 0.001). Separate data concerning the presence/absence of active inflammation showed a high kappa value (0.74, P < 0.001). Our results showed that a simple scintigraphic scoring system based on assessment using the human eye reflects colonic inflammation at least as well as computer-aided grading, and that highly correlated results can be achieved between different investigators.
Almer
S
S
Department of Internal Medicine, Faculty of Health Sciences, Linköping University, Sweden.
Peters
A M
AM
Ekberg
S
S
Franzén
L
L
Granerus
G
G
Ström
M
M
D000293:Adolescent; D000328:Adult; D000368:Aged; D003093:Colitis, Ulcerative / Q000175:diagnosis / Q000000981:diagnostic imaging*; D003106:Colon / Q000000981:diagnostic imaging; D003113:Colonoscopy; D004760:Enterocolitis / Q000175:diagnosis / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D007413:Intestinal Mucosa / Q000000981:diagnostic imaging; D007962:Leukocytes; D008297:Male; D008875:Middle Aged; D015609:Organotechnetium Compounds; D010091:Oximes; D011877:Radionuclide Imaging; D019690:Technetium Tc 99m Exametazime
D015609:Organotechnetium Compounds; D010091:Oximes; D019690:Technetium Tc 99m Exametazime