Diagnosis of diffuse idiopathic skeletal hyperostosis with chest computed tomography: inter-observer agreement

Abstract

ObjectiveTo evaluate and improve the interobserver agreement for the CT-based diagnosis of diffuse idiopathic skeletal hyperostosis (DISH).MethodsSix hundred participants of the CT arm of a lung cancer screening trial were randomly divided into two groups. The first 300 CTs were scored by five observers for the presence of DISH based on the original Resnick criteria for radiographs. After analysis of the data a consensus meeting was organised and the criteria were slightly modified regarding the definition of ‘contiguous’, the definition of ‘flowing ossifications’ and the viewing plane and window level. Subsequently, the second set of 300 CTs was scored by the same observers. κ ≥ 0.61 was considered good agreement.ResultsThe 600 male participants were on average 63.5 (SD 5.3) years old and had smoked on average 38.0 pack-years. In the first round κ values ranged from 0.32 to 0.74 and 7 out of 10 values were below 0.61. After the consensus meeting the interobserver agreement ranged from 0.51 to 0.86 and 3 out of 10 values were below 0.61. The agreement improved significantly.ConclusionsThis is the first study that reports interobserver agreement for the diagnosis of DISH on chest CT, showing mostly good agreement for modified Resnick criteria.Key Points• DISH is diagnosed on fluoroscopic and radiographic examinations using Resnick criteria • Evaluation of DISH on chest CT was modestly reproducible with the Resnick criteria • A consensus meeting and Resnick criteria modification improved inter-rater reliability for DISH • Reproducible CT criteria for DISH aids research into this poorly understood entity

Ectopic spinal calcification associated with diffuse idiopathic skeletal hyperostosis (DISH): A quantitative micro‐ct analysis

“…The vertical presentation we describe is in keeping with previous reports of "flowing" calcifications with bridging angles <45˚and >90˚, while the horizontal presentation we describe has previously been reported as sharp horizontal outgrowths, resembling osteophytes with bridging angles <90˚. 24,26,41 Interestingly, the most prominent presentation of large, horizontal outgrowths we detected (58%: n ¼ 44/76 motion segments) resembles what has been described as the "late, advanced, or terminal-stage" of DISH. 22,28,40,41 The discontinuous-patchy presentation described in the current study has been noted in previous reports as "unknown floating particles" requiring further characterization.…”

“…Bridging calcifications have been previously categorized based on the resultant bridging angle of the new calcified formation relative to the vertebral bodies. The vertical presentation we describe is in keeping with previous reports of “flowing” calcifications with bridging angles <45° and >90°, while the horizontal presentation we describe has previously been reported as sharp horizontal outgrowths, resembling osteophytes with bridging angles <90° . Interestingly, the most prominent presentation of large, horizontal outgrowths we detected (58%: n = 44/76 motion segments) resembles what has been described as the “late, advanced, or terminal‐stage” of DISH .…”

“…Specimens that met the radiographic criteria for DISH were assessed for volume of ectopic calcifications. Motion segments (i.e., single IVD and two adjacent vertebral bodies) were categorized based on the morphological appearance of bridging angle, that being >90° relative to the vertebrae for flowing calcifications, and <90° relative to the vertebrae for large outgrowths resembling osteophytes . For each motion segment, a region of interest (ROI) was manually contoured to capture the content of ectopic calcification for each specimen based on predetermined criteria: (i) external to the IVD, beyond the boundary created by connecting the adjacent superior‐inferior vertebral bodies (i.e., to include material outside the anatomical borders of the IVD); and (ii) bounded in axial height by the subchondral cortical bone of adjacent vertebral bodies (i.e., to include material associated within IVD height) (Supplemental Fig.…”

Prevalence of Diffuse Idiopathic Skeletal Hyperostosis Diagnosed by Whole Spine Computed Tomography: A Preliminary Study

“…Diagnosis by these CT scan images has been reported more reliable. 12 13 14) However, there is no report that evaluates epidemiology and etiology of DISH using whole spine CT scan images. Coprevalence of thoracic, cervical, and lumbar DISH can be evaluated by whole spine CT.…”

Dystrophic calcification and heterotopic ossification in fibrocartilaginous tissues of the spine in diffuse idiopathic skeletal hyperostosis (DISH)

“…2 These findings are in keeping with previous studies demonstrating degenerative changes in the IVDs of people with DISH. 31,32 Taken together, mild-to-moderate IVD degeneration should be reconsidered as an accompanying clinical scenario in the formation of ectopic mineral in DISH, since it is common in this population.…”