Lightspeed vct

An anonymous adult female, without history of middle ear pathology, underwent a TB CT-scan with a standard protocol for TB examination achieved by a “VCT lightspeed—General Electric healthcare Chicago Illinois U.S” with 0.625 mm sections. Both an otologist expert and a neuroradiologist expert corroborated that the whole TB was normal (29 (link)), namely: a good airing of mastoid cells, a good shape and position of the ear-drum, ossicles, facial nerve and inner-ear components and finally, no protrusion of sigmoid sinus. The left side has been chosen arbitrarily. The DICOM files obtained were then segmented (by otologists and medical engineers with Blender (30 ) free software) in order to extract: outer ear, ear-drum, middle ear with malleus, incus and stapes, inner ear with the whole labyrinth (cochlea, vestibule with semi-circular canals, fenestra vestibuli and fenestra cochleae), dura mater, sigmoid sinus and the facial nerve (with chorda tympani). A mesh model under a standard tessellation language (STL) format was then obtained and smoothed to fit for 3D-printing. We used different hardness of resins (“shores”) for hard (bone) and soft (facial nerve, chorda tympani, dura mater, sigmoid sinus, ear drum, fenestra vestibuli, fenestra cochleae, membranous semi-circular canals and skin) tissues. The whole and dissected final printed models are shown on Figure 1.

All patients underwent CT scan, performed with a 64-section scanner (VCT LightSpeed; GE Healthcare). The same MDCT protocol optimised for neuroendocrine tumours was performed in all patients. This included an unenhanced acquisition and two contrast-enhanced acquisitions (late arterial and portal venous phase) after intravenous administration of 2 mL/kg of non-ionic contrast medium (Xenetix, Guerbet, France).

¹¹C-PK11195-PET/CTA imaging of the carotid arteries was performed according to the protocol previously described by our group using a 64-slice CT scanner (VCT Lightspeed, GE Healthcare, USA) administering non-ionic, iso-osmolar contrast Iodixanol (Visipaque 320; GE) [9 (link)].

Two GE scanners were utilised between 2013 and 2021 (GE VCT lightspeed and GE Rev EVO). Each patient received Omnipaque 300 (Iohexol) contrast at 1.5 ml/kg in 35 ml saline with a flow rate of 2.5–4 ml s⁻¹. Image acquisition was obtained with a delay of 70 s post-contrast injection, acquiring 0.625 mm slices at 0.8 s tube rotation (Pitch – 1.375:1).
The image raw data were then transferred onto a GE workstation for processing and reconstruction. These were then transferred onto the Insignia Medical Systems Viewer for multiplanar viewing and analysis.