title: Diagnosis of drowning using post-mortem computed tomography based on the volume and density of fluid accumulation in the maxillary and sphenoid sinuses.
abstract: Recent studies have reported that drowning victims frequently have fluid accumulation in the paranasal sinuses, most notably the maxillary and sphenoid sinuses. However, in our previous study, many non-drowning victims also had fluid accumulation in the sinuses. Therefore, we evaluated the qualitative difference in fluid accumulation between drowning and non-drowning cases in the present study. Thirty-eight drowning and 73 non-drowning cases were investigated retrospectively. The fluid volume and density of each case were calculated using a DICOM workstation. The drowning cases were compared with the non-drowning cases using the Mann-Whitney U-test because the data showed non-normal distribution. The median fluid volume was 1.82 (range 0.02-11.7) ml in the drowning cases and 0.49 (0.03-8.7) ml in the non-drowning cases, and the median fluid density was 22 (-14 to 66) and 39 (-65 to 77) HU, respectively. Both volume and density differed significantly between the drowning and non-drowning cases (p=0.001, p=0.0007). Regarding cut-off levels in the ROC analysis, the points on the ROC curve closest (0, 1) were 1.03ml (sensitivity 68%, specificity 68%, PPV 53%, NPV 81%) and 27.5 HU (61%, 70%, 51%, 77%). The Youden indices were 1.03ml and 37.8 HU (84%, 51%, 47%, 86%). When the cut-off level was set at 1.03ml and 27.5HU, the sensitivity was 42%, specificity 45%, PPV 29% and NPV 60%. When the cut-off level was set at 1.03ml and 37.8HU, sensitivity was 58%, specificity 32%, PPV 31% and NPV 59%.
authors.affiliation: Tohoku University Graduate School of Medicine, Department of Clinical Imaging, 2-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi 980-8575, Japan. ssu@rad.med.tohoku.ac.jp
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Kawasumi
authors.forename: Tomoyoshi
authors.initials: T
authors.lastname: Kawabata
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Sugai
authors.forename: Akihito
authors.initials: A
authors.lastname: Usui
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Hosokai
authors.forename: Miho
authors.initials: M
authors.lastname: Sato
authors.forename: Haruo
authors.initials: H
authors.lastname: Saito
authors.forename: Tadashi
authors.initials: T
authors.lastname: Ishibashi
authors.forename: Yoshie
authors.initials: Y
authors.lastname: Hayashizaki
authors.forename: Masato
authors.initials: M
authors.lastname: Funayama
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001344:Autopsy / Q000379:methods*; D001826:Body Fluids / Q000000981:diagnostic imaging*; D002102:Cadaver; D004332:Drowning / Q000000981:diagnostic imaging*; D005260:Female; D049429:Forensic Pathology / Q000379:methods*; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods; D008297:Male; D008443:Maxillary Sinus / Q000000981:diagnostic imaging*; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013101:Sphenoid Sinus / Q000000981:diagnostic imaging*; D014057:Tomography, X-Ray Computed / Q000379:methods*
keywords: CT; Computed tomography; DICOM; Drowning; Forensic medicine; MDCT; NPV; PPV; Paranasal sinuses; Post-mortem changes; ROC; computed tomography; digital imaging and communication in medicine; multi-detector computed tomography; negative predictive value; positive predictive value; receiver operating characteristic