DENTAL IMAGING DILEMMAS IN KLIPPEL-FEIL ANOMALY

Background Because of the broad range of findings, Klippel-Feil syndrome has also been referred to as Klippel-Feil sequence and Klippel-Feil anomaly. It is classified into 3 types that differ in degree and location of vertebral fusion. Another contemporary classification also includes patterns of inheritance. Case Report A 19-year-old male needed panoramic imaging to evaluate his third molars. However, because of Klippel-Feil disfigurement, his head and neck posture did not fit into various panoramic imaging units. With an altered oblique head positioning in a cone beam computed tomography (CBCT) scanner (NewTom VGi), his jaws were scanned. The CBCT volumetric data were then realigned and reconstructed in CBCT viewing software (InVivoDental 6.0). These reconstructions were appropriate to assess the indicated dental status and to update the assessment of the cervical vertebral development—a limiting condition of Klippel-Feil syndrome. Definitive Interpretation The scan data were able to provide the indicated periapical assessment, particularly of the third molars. Postural compromises were also noted in the anterior alignment of the odontoid process–C1 articulation and their alignment to the clivus of the occipital bone. There was also cervical vertebral aplasia with complete fusion of C2-C7. These findings were contributory to his altered posture. Discussion of Imaging The availability of large volume CBCT scanners, with their larger footprint, scanning circumference, and larger scanning size area, provide an imaging option for patients with mental and physical disabilities. In the past, a single large field of view (FOV) CBCT scan has been purported by CBCT manufacturers to be a one-stop imaging solution for all extraoral imaging. Dosimetry data and FDA selection criteria have since contraindicated the use of large volume FOV scanning to replace standard periapical, panoramic, and cephalometric imaging. This case report supports the alternative use of CBCT to acquire standard extraoral images when standard imaging is not possible. Because of the broad range of findings, Klippel-Feil syndrome has also been referred to as Klippel-Feil sequence and Klippel-Feil anomaly. It is classified into 3 types that differ in degree and location of vertebral fusion. Another contemporary classification also includes patterns of inheritance. A 19-year-old male needed panoramic imaging to evaluate his third molars. However, because of Klippel-Feil disfigurement, his head and neck posture did not fit into various panoramic imaging units. With an altered oblique head positioning in a cone beam computed tomography (CBCT) scanner (NewTom VGi), his jaws were scanned. The CBCT volumetric data were then realigned and reconstructed in CBCT viewing software (InVivoDental 6.0). These reconstructions were appropriate to assess the indicated dental status and to update the assessment of the cervical vertebral development—a limiting condition of Klippel-Feil syndrome. The scan data were able to provide the indicated periapical assessment, particularly of the third molars. Postural compromises were also noted in the anterior alignment of the odontoid process–C1 articulation and their alignment to the clivus of the occipital bone. There was also cervical vertebral aplasia with complete fusion of C2-C7. These findings were contributory to his altered posture. The availability of large volume CBCT scanners, with their larger footprint, scanning circumference, and larger scanning size area, provide an imaging option for patients with mental and physical disabilities. In the past, a single large field of view (FOV) CBCT scan has been purported by CBCT manufacturers to be a one-stop imaging solution for all extraoral imaging. Dosimetry data and FDA selection criteria have since contraindicated the use of large volume FOV scanning to replace standard periapical, panoramic, and cephalometric imaging. This case report supports the alternative use of CBCT to acquire standard extraoral images when standard imaging is not possible.