Saturday 11 September 2021

ENT Otolaringology Neurology
MSK Musculoscheletal
Diagnostic Technology
Welcome Coffee
Welcome speech
Prof. Enrico Gherlone
9:10 - 9:30
Event introduction
Prof. Francesco De Cobelli
Moderator: Francesco Sardanelli - Raffaele Vinci
How Cone Beam CT indications evolved and future expectations
Prof. Jan W. Casselman (Abstract)

Prof. Jan W. Casselman

How Cone Beam CT indications evolved and future expectations.
A lot changed since the early days of CT, when only dental and sinus studies were performed. 3D maxillofacial, TMJ, orbit and MSK studies followed. Systems capable of providing higher resolution made CBCT of the temporal bone possible. Dynamic studies became feasible on CBCT systems on which the rotation could be stopped during acquisiton. The 7G opened new perspectives with cervical and lumbar spine imaging, shoulder and hip imaging, full leg imaging, imaging during arthroscopy etc. The above indications will be discussed as well as future challenges and possibilities of CBCT.


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Image quality and exposure parameters of CBCT
Prof. Zuyan Zhang (Abstract)

Prof. Zuyan Zhang

Image quality and exposure parameters of CBCT
Department of Oral and Maxillofacial Radiology, Peking University School of Stomatology. The purpose of this study was to investigate the image quality of cone beam computed tomography under different exposure parameters and the relationship between contrast-to-noise and visibility of 8 anatomical structures. CBCT images for the evaluation of subjective image quality were acquired on an anthropopathic phantom containing a human skeleton embedded in soft tissue equivalent materials using 25 exposure protocols. Visibility of 8 anatomical structures was evaluated by 5 independent observers. Using the SEDENTEXCT IQ Image Quality phantom, the CNR was calculated by ImageJ software. The results demonstrated reduction on the visibility of anatomical structures under lower exposure parameters. However, for 84% of the protocols, visibility of anatomical structures remained acceptable even under some lower parameter settings. As CNR increased, the visibility of anatomical structures also increased correspondingly. A change point could be found in the CNR interval 29.42-36.51 after which the visibility of anatomical structures no longer increases with the increase of CNR. As a conclusions, although CNR decrease under a lower exposure parameter, the image quality often remained acceptable at exposure levels below the manufacture’s recommended settings. Currently, it is not possible to predetermine a change point of CNR value due to different CBCT machine and variation of diagnostic tasks.


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CBCT and Contrast Media: Arthrography of temporomandibular Disorders & Parotid Sialography
Prof. Donglin Zeng (Abstract)

Prof. Donglin Zeng

CBCT and Contract Media: Arthrography of temporomandibular Disorders & Parotid Sialografy
Section 1 - Objective To evaluate the meaning of arthrography with cone‑beam CT (CBCT) imaging in the diagnosis of temporomandibular disorders(TMD).
Four hundred and forty-eight cases of temporomandibular upper joint cavity arthrography with CBCT imaging were retrospectively analyzed. The distribution of disc displacement with reduction or without reduction, disc perforation, enlargement or tearing of joint capsule were analyzed. The characteristics of arthrography with CBCT imaging were also described. Results There were 384 female and 64 male among the 448 cases of TMD with CBCT arthrographic images. The median age was 31.5 years, range from 14 to 81 years old. As about the age distribution, there were 63 cases in the group of ≤20 years old, 150 cases in the group of >20 and ≤30 years old, 86 cases in the group of >30 and ≤40 years old, 59 cases in the group of >40 and ≤50 years old, 58 cases in the group of>50 and ≤60 years old, and 32 cases in the group of >60 years old. There were 356 cases with disc displacement, in which there were 328 cases of disc displacement without reduction, and 28 cases of disc displacement with reduction. There were 152 cases with disc perforation, and 12 cases with articular capsule tearing or laxation. Conclusions Arthrography with CBCT imaging was a meaningful approach to diagnose the TMD with structure disorders.

Section 2 - To study the characteristics of three-dimensional visualization image of cone-beam computed tomography (CBCT)
in parotid sialography. Methods 25 cases of CBCT image in parotid sialography were retrospective analyzed. The three dimensional visualization techniques, such as Multi Planar Reconstruction (MPR)、Maximum Intensity Projection (MIP) and Volume Rendering (VR),were performed to reconstruct the images. The character of image shown by each technique was discussed. Results 12 cases with chronic obstructive parotitis, 7 cases with recurrent parotitis and 6 cases with benign tumor were identified. The acinus system and ducts system of parotid were clearly displayed from any orientation by MPR, MIP and VR. The gland could be displayed slice to slice by MPR. However,it couldn′ t be done by MIP and VR. VR could only show the surface image of the gland and the main duct. The internal and surrounding structures of parotid were clearly shown by MPR. The regular acinuses look like cloud and mist in MPR. The gland lobulars were separated by fibrous tissue and look like accumulated cloud in MPR. The branch conducts were also clearly shown by MPR. On the other hand,MIP could clearly display acinuses and ducts as whole. Normal acinuses were shown as dilute cloud in MIP. The main duct and branch ducts displayed by MIP were clearer than that shown by MPR. Finally,it was difficult to identify the location of lesions which occurred in interior of the gland by MIP and VR. CBCT image in parotid sialography could clearly show the acinus and ducts system. In order to do precise judgment and accurate localization of the lesion in parotid, MPR and MIP analysis technique might be used together.


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Coffee Break

Moderators: Anna Del Poggio – Matteo Trimarchi
The Integration of CBCT in Skull Base Imaging
Prof. Roberto Maroldi (Abstract)

Prof. Roberto Maroldi

The Integration of CBCT in Skull Base Imaging
Several lesions near or involving the anterior or middle skull base require a thorough examination of the structures that separate the intracranial or orbital contents from the sinonasal cavities. While some "separators" are made of thick bone, others are composed of very thin bone or are traversed by tiny channels and foramina. Most of these "separators" are not directly accessible to a pre-treatment endoscopic evaluation. Imaging has the role to define the precise state of the thin or thick "separator" composing that part of the skull base. CBCT allows to analyse the bone framework of the skull base with a very high spatial resolution. Working with 3D volumes with 200-micron pixel sizes allows for a very detailed assessment of osseous anatomy and abnormalities. The patterns of bone changes seen on CBCT may help to precisely orient the understanding of the "mechanism" responsible for that bone alteration. Thinning, bone remodeling, focal or extensive resorption, destruction, thickening of bony lamellae, sclerosis of spongiosa are among the patterns that can be very accurately detailed by CBCT. It has to be considered that the "separators" are made by bone, but they are invested by soft layers (periosteum, dura mater). When the mineral content of the bone is resorbed, causing it to "disappear" on CBCT images, the current state of its soft tissue investing layers, i.e., integrity or alteration, requires the integration of CBCT with MRI. For example, if a CSF leak is suspected, a single or multiple focal bony defect(s) of the anterior skull base floor with sessile polypoid tissue projecting through the defect may indicate menigocele(s). In this case, multiparametric MRI should be advocated to examine the content of the polypoid lesions. And MRI is also indicated to separate the signal of secretions blocked within cells or sinuses from the solid signal of neoplasms. As a result, the integration of CBCT and MRI is critical for achieving a proper assessment of lesions "touching" or "extending from" the skull base. The combination of the two tecniques provides valuable information for both diagnosis and surgical treatment planning. The "fusion" of the two sets of 3D data may improve understanding of the anatomy and the key relationship of the target lesion with critical structures even further.


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Cone Beam in normal and pathological ear
Prof. Francis Veillon (Abstract)

Prof. Francis Veillon

Cone Beam in normal and pathological ear
Parte 1 – Orecchio normale
Section 1 – Normal ear
General - The normal image of the ear by Cone Beam benefits from an improvement in spatial resolution at low dose (< 16 mGy) with a slice thickness of 0.1 mm, while reducing the possibilities of mobility artefacts by adopting the supine position. The technique is based on a multiplanar approach systematically associating the axial and coronal planes, oblique planes in the axis of the incus and the stapes, zoomed sections on the windows. The axial plane must be practiced in the axis of the lateral semicircular canal from the sagittal and frontal landmarks. A criterion for good examination quality is the axial visualization of the entire lateral semicircular canal visible on the same section as the labyrinthine portion of the facial canal. This approach only makes it possible to correctly analyze the labyrinth but also and above all to properly assess the footplate allowing a precise diagnosis of otosclerosis, inflammations calcified or not, malformations, trauma. The overall axial plane of the temporal bone (covering the 6 cm of the rock) It should be performed from the lower part of the external auditory meatus to a level passing above the convexity of the superior semicircular canal. It allows an evaluation of the petrous apex in front, of the mastoid behind, of the anterior, posterior bony walls of the external auditory canal, of possible calcifications of the tympanic membrane, of the aeration of the whole ear, at the level of the epitympanum, the protympanum, the middle mesotympanum, the retrotympanum, the hypotympanum. It also allows an analysis of the windows, the shape and size of the labyrinth (cochlea in front, vestibule, semicircular canals behind), the presence or not of the modiolus, the appearance of the canals at the fundus of the internal auditory meatus the configuration of the three portions of the facial canal, the lateral wall of the jugular foramen, the location of the intrapetrous carotid canal. The coronal plane of the temporal bone It is positioned about 80 ° to the plane of the lateral semicircular canal between a section passing behind the mastoid facial canal and the middle part of the petrous apex in front of the cochlea. It allows to evaluate the external auditory canal: its size, its shape, the integrity of its floor. This plan easily shows the appearance of the wall of the epitympan, the lower edge of which, in particular in front, must present a clearly acute angle. The integrity, whether or not the roof of the tympanic cavity is lowered, the thickness of the labyrinth roof, the height of the oval window (1.5 mm minimum), the width of the round window (1.5 mm minimum) also fall under this plan. The sagittal plane It is useful for evaluating the bony walls of the external auditory canal, the height of the jugular foramen in relation to the floor of the internal acoustic meatus. Like the coronal plane, it specifies the integrity of the roof of the tympanic cavity. The bony endolymphatic duct contains the membrane duct of the same name, the diameter of which should not exceed 1.5 mm. Oblique planes. A first section passes through the incus in its long axis allowing in MIP mode to analyze the body and the long incudal process but also the malleus as a whole. The second section goes through the stapes showing the head and the crura thus highlighting the excellent spatial resolution of the Cone Beam. Zoomed sections There are 60 in the axial plane every 0.2 mm, useful for the pathology of windows, in particular otosclerosis, calcium deposits and malformations. Ultimately, the Cone Beam of the ears by the excellent spatial resolution has become an essential instrument in the assessment of deafness in particular of transmission in order to guide the therapeutic attitude.

Section 2 – Pathological ear
General - The main pathologies of the ear are malformations, inflammations and their complications, trauma, otosclerosis and tumors. The external auditory canal. The malformations can affect in a combined or separate way the three cavities of the ear: external, middle, internal. Regarding the external auditory canal, there is agenesis or stenosis. The inflammatory pathology can be the result of a fairly aggressive process, such as in necrotizing external otitis where signs of osteolysis can be more or less visible. Obturating keratosis results in a fairly typical external meatal enlargement, whereas cholesteatoma by defective evacuation of the scales is characterized by erosion of the bone floor. The tympanic bone is affected by 50% of traumas with more or less severe fractures causing otorrhagia. Tumor pathology is mostly benign with bilateral exostoses giving a fairly typical trefoil appearance opposing osteomas with a rather lateral development visible only on one side. Carcinomas are rarer and rather visible in the elderly, sometimes very destructive, they can in some cases simulate lesions presumed benign because they are not very invasive. Tumors by extension of the middle ear type paraganglioma, meningioma, schwannoma of the facial nerve are rarer. The middle ear The malformations of the middle ear if they can integrate small cavities are distinguished especially by the possibilities of fusion, fixation, deformation, absence of certain ossicles. The easiest to treat is the absence of the long process with persistence of a stapes. It should be noted that the tympanic facial canal is often lateralized in the event of a malformation of the size of the middle ear. The stapes can be malformed with a tuning fork aspect or be distinguished by the presence of a single crus. The platinum is sometimes deformed, thickened or normal if there is an abnormality of the adjacent annular ligament. Inflammatory pathology is extremely common within the tympanic cavity. It can be distinguished by fluid levels reflecting serous otitis which should challenge clinicians and radiologists when there is no reported inflammatory past. Calcifications can punctuate the tympanic membrane, ligaments and tendons to a greater or lesser extent, sometimes transforming into ossified blocks leading to osteomatous otitis. Cholesteatomas represent an accumulation of epidermis in general at the level of the epitympan but sometimes also in the meso or more rarely the hypotympanum. They frequently develop from membrane retraction pockets, of spherical or semi-spherical shape, with regular or irregular contours, they can be small, limited to a few millimeters, on the contrary more developed from 10 to 20 mm. In about 7% of cases they cause a more or less important opening, especially in the convexity of the lateral semicircular canal, more rarely at the level of the other two semicircular canals. The Cone Beam is useful for analyzing the persistence or not of the endosteum in the event of canal erosion. Trauma with fractures affects the middle ear in more than 85% of cases. They enter this cavity by different entry zones in front, above, behind the external auditory canal, by the posterior and superior petro-squamous fissure, by the mastoid or finally by the internal face of the petrous bone. They can generate contusions or even injuries of the facial nerve by bone spicules, most often in the geniculate ganglion to be treated by the surgeon. If the patient is transportable, its positioning in the Cone Beam can be extremely advantageous in detecting these traumatic lesions. Movements of the ossicles, fractures in particular of the crura of the stapes or of the footplate generally lead to a surgical procedure. Tumors They are rather rare, to cite among others: The schwannoma of the facial nerve, the meningiomas coming either from the middle cranial fossa or from its posterior counterpart, the paragangliomas having their origin either in the tympanic canal or around the jugular foramen. Inner ear Otosclerosis. - This pathology is very interesting to study by Cone Beam because it includes more or less small hypodensities sometimes multiple generally localized in the middle part of the anterior labyrinthine capsule most often in front of the oval window (four types of otosclerosis of I to IV can be individualized). The footplate can be thickened in general rather hypodense with a bayonet-shaped profile. The otosclerotic focus may extend cranially inside the tympanic facial canal or, on the contrary, descend on the promontory. The height of the oval window can thus be reduced either from above or from below. The round window can be implied by hypodensities at the level of the external and / or internal edges to be classified in grades from II to IV, the latter being distinguished by the presence of calcium in the scala tympani. The Cone Beam is also an excellent way to assess the position of the prosthetic material used by the surgeon as part of the treatment. Malformations Minor, they are extremely frequent, characterized by the appearance of a double lateral canal bulb, of a small islet circumscribed by the horizontal semicircular canal or by a lack of segmentation between the 2nd and 3rd turns of the cochlea, whether bilateral or not. Sometimes larger congenital anomalies can be encountered with partial cochlear segmentations with or without the presence of modiolus or small cochleas with or without modiolus. Dilation of the bony endolymphatic duct may be associated with these labyrinth-shaped abnormalities. The presence or absence of modiolus is absolutely decisive for the radiologist to diagnose in order to prevent the surgeon from intraoperative disappointments in the treatment of certain conductive hearing loss. Inflammations If inflammatory lesions of the labyrinth are essentially the result of MRI, the Cone Beam may nevertheless have an interest in the detection of small calcifications often localized at the level of the tympanic ramp of the lower part of the first turn or at the level of the semicircular canals. resulting in the diagnosis of ossifying labyrinthitis. Trauma Labyrinth trauma accounts for just over 10% of all temporal bone damage. They often involve the participation of the oval and round windows causing perilymphatic fluid fistula requiring surgical treatment. The Cone Beam has all its interest in this matter because these lesions are sometimes difficult to see. In some cases there is no fracture of the windows but simply an effusion of external fluid from the inner ear causing one or both windows to be filled. The combination with an injected MRI will make it possible to make the diagnosis. The dehiscence of the convexity of the semicircular canal greater than or equal to 3 mm should be noted in the active part of the Cone Beam because it often complicates a head trauma. Ultimately the Cone Beam is the future of ear imaging as its spatial resolution facilitates the various diagnoses allowing precise preoperative assessments or on the contrary to avoid surgical procedures not indicated.


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CBCT Imaging of Patients with Medication Related Osteonecrosis of the Jaws (MRONJ)
Prof. Sotirios Tetradis (Abstract discorso)

Prof. Sotirios Tetradis

CBCT Imaging of Patients with Medication Related Osteonecrosis of the Jaws (MRONJ)
Medication related osteonecrosis of the jaws (MRONJ) is a rare but serious side effect of antiresorptive and antiangiogenic medications. MRONJ is defined as exposed bone or bone that can be proved through an intraoral or extraoral fistula in the maxillofacial region that has persistent for more than eight weeks. Most patients with MRONJ have a history of antiresorptive medications for management of primary or metastatic malignance to the bones or for osteoporosis. Although MRONJ is mostly diagnosed clinically, radiographic imaging is central to assess the extent of the disease and for follow up during patient management. Imaging is also very important in the diagnosis of patients with Stage 0 MRONJ, without frank bone exposure. From all imaging modalities, CBCT offers great advantages. The three-dimensional depiction of anatomic structures by CBCT provides an improved assessment of salient and subtle disease features over conventional two-dimensional radiographs. Furthermore, ease and availability of CBCT in the dental office setting allows utilization of the technology in a great sector of patients with MRONJ-like symptoms. Classic radiographic features of MRONJ include increased trabecular sclerosis, erosions of the cortical boundaries, osteolysis, non-healed extraction sockets, crate-like defects, fistula tract formation, periosteal reaction and sequestration. In advanced stages of the disease, effects in adjacent structures might include pathologic fractures and involvement of the maxillary sinus or the nasal cavity. However, the MRONJ radiographic features are not specific and can be present in other inflammatory conditions, such as osteomyelitis or osteoradionecrosis. In this presentation, the contribution of radiographic imaging and in particular of CBCT scanning in the assessment of the patient with frank or suspected MRONJ will be discussed and the classic MRONJ radiographic findings will be compared and contrasted with findings from other diseases with similar appearance. The correlation of radiographic and clinical findings will be considered and a flowchart for decision making of the imaging needs for patients on antiresorptive medications will be introduced.


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Moderators: Giorgio Gastaldi – Enrico L. Agliardi
The artificial wonders of CBCT
Prof. Reinhilde Jacobs (Abstract discorso)

Prof. Reinhilde Jacobs

The artificial wonders of CBCT
Digital dentistry goes hand in hand with dental imaging. During the last decade, 3D imaging has started to play a dominant role in daily practice, not only in relation to radiologic diagnosis, yet and surely also in relation to surgical and treatment planning. These changes may create a need to redefine the role of dentomaxillofacial radiologists within the dental team. This digital evolution may also require to reconsider education and training. Digital 3D imaging may even revolutionize oral healthcare by the introduction of artificial intelligence and its great potential for education, diagnosis and treatment planning. We may need to wonder how AI-based CBCT diagnosis and treatment could help clinicians to reshape the future of dentistry.


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Excessive Bilateral maxillary and mandibular buccal exostosis: a 4-years follow up case study. The journey behind a confident smile.
Dr. Majd Naji (Abstract)

Dr. Majd Naji

Excessive Bilateral maxillary and mandibular buccal exostosis: A 4-years follow up case study. The journey behind a confident smile.
Buccal exostoses are broad-based, non-malignant surface growth occurring on the outer or facial surface of the maxilla and/or mandible, found usually in the premolar/molar region and the anterior region. Etiology is unknown , but it has been suggested that the bony overgrowth can be because of abnormally increased masticatory forces to the teeth and the supporting structures. They tend to appear in early adolescence and may very slowly increase in size with time. They are painless and may increase patient concern about poor esthetics, inability to perform oral hygiene procedures, and compromised periodontal health.The following case report presents a very rare case of bilateral buccal-sided maxillary and mandibular exostoses and its management with surgical intervention and implant-supported restoration to improve aesthetics and oral hygiene measures.


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CBCT as essential instrument for modern Dentistry
Dr. Mario Cappellin (Abstract)

Dr. Mario Cappellin

- CBCT as essential instrument for modern Dentistry
The introduction of CBCT boosted substantial innovations in dental surgery and implantology, allowing dentists to speed up timing and to reduce invasive character of interventions, increasing their reliability and safety: from computer guided surgery to 3D printed bone models, CBCT scans are fundamental for diagnosis and surgical planning. The speech is going to present several clinical cases to illustrate the numerous applications of CBCT in the most updated digital flow in Dentistry.


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Moderators Francesco De Cobelli – Alberto Aliprandi
CBCT at MSK. Contributions of Cone Beam technology in the daily clinic. 5 years experience.
Prof. Jordi Catala (Abstract)

Prof. Jordi Catala

CBCT at MSK. Contributions of Cone Beam technology in the daily clinic. 5 years experience.
Since the introduction of CBCT in dental pathology, we have acquired experience for more than 5 years, in applying this technology in other medical applications. In this conference, we will discuss about clinical decisions in MSK, as a consequence of the advantages of this technique: ultra-low dose, thin slices, high resolution and isotropic reconstructions. We will also discuss about the contribution of the NewTom models, from the GiANO, VGi evo, 5GXL, and the new 7G incorporation, with patient comfort and applications in joints such as hip and shoulder. We will show clinical cases of the implementation of the CBCT technology in MSK, in detection and follow-up of fractures, ArthroCBCT, surgeries and osteosynthesis, specific protocols such as rotation of the lower extremities and evaluation of prosthesis stability, rotational study in the craniocervical union and CineX, as well as initial experience in tumours, and biopsy guide. We will report the application of biomarkers in MSK as determination of the concentration of GAG's in cartilage, determination of the quality of the trabecular structure, etc. We will finish with information on the installation and maintenance costs, and marketing, in our experience in our clinical and economic environment.


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Simulated weight-bearing CT of the foot and ankle with a NewTom 5GXL
Dott. Ricardo Trueba (Abstract)

Prof. Ricardo Trueba

Simulated weight-bearing CT of the foot and ankle with a NewTom 5GXL
Throughout the years, the diagnosis and classification of the leg, ankle, and foot pathologies was carried out through frontal and profile load radiographs, to which different radiographs were added over the years (axial, sesamoid, axial calcaneus, axial Harris, Broden, oblique, etc.) but despite their incorporation, the same limitation was always encountered, which was that said images obtained only reflected information in two planes and thus generating images overlapping. With the passing of the years and evolution by imaging studies, computed tomography began to be used, which generated information in three planes unlike radiography, but the drawback was that as it was not reproduced with the load on the limb inferior to study, there was still a lack of more reliable information about the foot. Starting in 2012, loading computed tomography began to be incorporated as a study, which did provide the specialist with more complete and reliable information to the specialist. In addition to providing a clinical image of the foot and its low levels of radiation. Given the information in three planes that this study generates, we believe it is essential to use it when diagnosing pathologies and to generate better pre-surgical planning by the specialist surgeon, but as in many parts of the world and given the situation Worldwide, it was almost impossible to obtain a specific tomography, in addition to the fact that this device is only used to perform load-bearing computed tomography of the lower limb. Therefore, what we did was develop a load simulation device (SIM), which can be used in the Cone Beam Tomograph with a stretcher, which, added to the benefits of low radiation, optimal images, and the acquisition of the clinical image of the member to be studied, it can be used to study other body segments. In this last year, we have been developing this study on different patients, with different specialists and leg, ankle, and foot surgeons. Where, for example, a therapeutic algorithm is developed for the treatment of hallux valgus, evaluating said pathology in three planes to achieve a more specific treatment concerning a quality that is being studied lately, such as the rotation of the first ray. Calculating the different angles (alpha, IMT, Meary, etc.) In this way to achieve better planning and then control with the loaded computed tomography thus accurately evaluating the rotational osteotomies performed. On the other hand, flat feet were evaluated, where it was possible to calculate the varus-valgus of the hindfoot, flattening of the medial longitudinal arch, and the real uncovered head of the talus by the navicular, thus managing to apply the indicated therapy. Another benefit that we found in the evaluation of articular surfaces and deformities that present the ankle and the foot in a more precise and exact way to carry out the most precise resection.


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CBCT: technological development and future advances
Prof. Pierluigi Mozzo – Dr. Attilio Tacconi (Abstract)

Dr. Pierluigi Mozzo – Ing. Attilio Tacconi

CBCT: technological development and future advances
In 1996 the first commercial CBCT was introduced in the market and quickly became an important imaging tool in oral and maxillofacial radiology. In this presentation we provide an overview of the advance of this technology, from the first approaches with the old Image Intensifier based detectors and systems dedicated to maxillofacial structures to the latest evolutions towards total-body machines, with powerful x-ray sources and modern, high performance, digital flat panels.The evolution will be treated in comparison with the parallel evolution of conventional CT, highlighting the advantages and limits of Cone Beam technology. Future trends and possible new technical developments will be discussed with special reference to the interesting spectral application of the technique.


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Closing remarks and conclusion