The recent development of extended reality technology has attracted interest in medicine. We explored the use of patient-specific virtual reality (VR) and mixed reality (MR) temporal bone models in ...anatomical teaching, pre-operative surgical planning and intra-operative surgical referencing.
VR and MR temporal bone models were created and visualized on head-mounted display (HMD) and MR headset respectively, by a novel webservice that allows users to convert computed tomography images to VR and MR images without specific knowledge of programming. Eleven otorhinolaryngology trainees and specialists were asked to manipulate the healthy VR temporal bone model and to assess its validity by filling out a questionnaire. Additionally, VR and MR pathological models of petrous apex cholesteatoma were utilized for surgical planning pre-operatively and for referring to the anatomy during the surgery.
Most participants were favorable about the VR model and considered HMD as superior to a flat computer screen. 91% of the participants agreed or somewhat agreed that VR through HMD is cost effective. In addition, the VR pathological model was used for planning and sharing the surgical approach during a pre-operative surgical conference. The MR headset was worn intra-operatively to clarify the relationship between the pathological lesion and vital anatomical structures.
Regardless of the participants’ training level in otorhinolaryngology or VR experience, all participants agreed that the VR temporal bone model is useful for anatomical education. Furthermore, the creation of patient-specific VR and MR models using the webservice and their pre- and intra-operative usages indicated the potential of innovative adjunctive surgical instrument.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Background: Quantification of main sequence is required for three-dimensional recording and analysis of eye movement using video-oculography. However, the main sequence of torsional saccade has not ...been reported to the best of our knowledge.
Aims/objectives: To obtain characteristics of torsional saccade using infra-red video-oculography, and to analyse the main sequence.
Material and methods: Torsional saccades of 10 healthy subjects were extracted from torsional vestibulo-ocular reflex from voluntary head rotation. Angular velocities were plotted against amplitude of each saccade to obtain the main sequence of torsional saccade.
Results: Main sequence of torsional saccade demonstrated non-linear characteristic. The adduction amplitude was significantly larger than abduction, while there was no significant difference in time constants.
Conclusions and significance: Torsional saccade demonstrates non-linear characteristic, similar to main sequence of vertical and horizontal saccades.
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DOBA, IJS, IZUM, KILJ, NUK, OILJ, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK, VSZLJ
Lateral temporal bone resection (LTBR) is performed for stage T1-2 external ear malignant tumors and requires spatial anatomical knowledge of the rare surgical field.
This paper presents a novel ...virtual reality (VR) based surgical simulation and navigation system using only commercially available display device and an online software, to assist in the understanding of the anatomy pre and intraoperatively.
VR model created by 3D Slicer modules and visualized on head mounted display enabled users to simulate and learn surgical techniques of a rare surgical case. 3D hologram through HoloLens assisted the surgeon in comprehending the spatial relationship between crucial vital structures and the pathological lesion during the operation. This platform does not require the users to possess specific programming skill or knowledge, and is therefore applicable in daily clinical usage.
●Lateral temporal bone resection (LTBR) is standard operative procedure for early-staged malignant tumors of external ear canals.●However, many surgeons lack the opportunity to learn the surgical techniques because of its rarity.●We report a usage of novel virtual reality based surgical simulation and navigation system for studying the anatomy and the operative steps in LTBR.●3D holograms with head-mounted display will provide revolutionary tool in assisting surgical planning, intraoperative referencing and navigation of otologic and skull base surgery.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
This retrospective study aimed to examine the course and prognosis of medication-related osteonecrosis of the jaw (MRONJ) initially treated conservatively and the effects of various factors affecting ...treatment outcomes. We evaluated 129 patients with MRONJ between January 2008 and December 2018 at a university hospital. The factors examined included sex, age, stage of MRONJ (1–3), type of bone modifying agents (bisphosphonate or denosumab), primary disease (osteoporosis or malignant tumor), medical history (diabetes and rheumatoid arthritis), use of corticosteroids, the trigger of MRONJ (teeth extraction or others), and separation of sequestrum, using logistic regression analysis. Patients with MRONJ were treated conservatively as the initial treatment in accordance with the position paper of the American Association of Oral and Maxillofacial Surgeons. Of the 129 patients, 59 (45.7%) were cured, and the condition of 70 (54.3%) remained unchanged or worsened. The overall cure rates at 12, 36, and 60 months were 25.8%, 50.8%, and 72.4% respectively. The cure rate of stage 1 was lower than that of stages 2 and 3 at 80 months. In multivariate analysis, it was found that 37 (64.9%) of 57 patients with osteoporosis as a primary disease were cured (odds ratio OR, 7.7; 95% confidence interval CI, 2.4–24.4). In addition, 40 (69.0%) of 58 patients with separation of sequestrum were cured (OR, 8.9; 95% CI, 3.4–23.5). The cure rate was significantly higher in patients with osteoporosis than in those with cancer when the treatment outcomes of primary disease were compared using the Kaplan-Meier method (p < 0.01). It was also significantly higher in patients who had separation of sequestrum than in those who did not (p < 0.05). Our results suggest that primary disease and separation of sequestrum were associated with favorable outcomes in patients with MRONJ initially treated conservatively. MRONJ had a poor prognosis with conventional treatment carried according to the stage of the disease. This was especially prominent when conservative treatment was employed for mild cases.
•Of the 129 patients with MRONJ, 59 (45.7%) were cured, and the condition of 70 (54.3%) remained unchanged or worsened.•The cure rate of stage 1 was lower than that of stages 2 and 3 at 80 months.•Primary disease and separation of sequestrum were associated with outcomes in MRONJ initially treated conservatively.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Recording eye movement at a patient's first visit to primary care is critical, because abnormal eye movement findings can disappear, accompanied by a lessening of symptoms. In addition, sharing such ...data with an expert institution can support a precise diagnosis. However, recording devices such as ENG and VOG are relatively expensive to introduce to private clinics. In addition, the series of eye movement examinations can take a relatively long time, potentially delaying other medical care. Recent advances in virtual reality (VR) technology have led to the development of VR goggles, which can project 3D images and also record eye movements. This kind of device can be a useful tool for the development of a novel and affordable instrument for private clinics. We have been participating in the development of a VR goggle-based VOG. This device can record ordinary sequential examinations automatically, to save time. At the same time, we are also developing an advanced model for specialists. In this manuscript, we introduce our novel VOG equipment. In addition, we discuss the possibility of future applications.
The Barany society has established international diagnostic criteria for nine vestibular disorders so far. The Japanese society of equilibrium research (JSER) developed the diagnostic criteria for ...five vestibular disorders in 2017, three of which overlap with those of the Barany Society. Thus, both domestic and international diagnostic criteria should be considered in Japan. In addition, some cases may meet the diagnostic criteria of more than one disease. The increasing number of diagnostic criteria makes it difficult for doctors to consider all of them within the limited amount of time available in outpatient settings. Therefore, we developed a system using Microsoft Excel to comprehensively determine whether the symptoms and signs of a patient meet the diagnostic criteria for multiple vestibular disorders, by inputting information from a questionnaire and examination findings. The diseases whose diagnostic criteria were included were Meniere's disease, delayed endolymphatic hydrops, vestibular neuritis, and benign paroxysmal positional vertigo in the 2017 revision of JSER, and Meniere's disease, vestibular migraine, vestibular paroxysmia, persistent postural-perceptual dizziness, bilateral vestibulopathy, presbyvestibulopathy, and hemodynamic orthostatic dizziness/vertigo in the Barany society. The questionnaire was designed to allow patients to answer multiple-choice questions regarding vestibular symptoms, the distinction between paroxysmal and non-paroxysmal vertigo, number of attacks, duration of attacks, provoking or aggravating factors, auditory symptoms, presence of migraine, and other accompanying symptoms. The system can be easily installed in a medical terminal and is expected to contribute to the efficiency of diagnosis and treatment of vestibular disorders.
The present study aimed to observe and analyze the ocular movements induced by Coriolis stimulation (eccentric pitch while rotating: PWR) that induces Coriolis forces on the vestibular apparatus of ...healthy human individuals.
A total of 31 healthy subjects participated in the study. Eccentric PWR was performed on 27 subjects, by pitching the participants’ heads forward and backward at an angle of 30° each on an axis parallel and 7 cm below inter-aural axis, at a frequency of 0.5 Hz while on a chair rotating at a constant angular velocity of 97.2°/s on the earth-vertical axis. Ocular movements during stimulation were recorded using three-dimensional video-oculography. As a subsidiary analysis, 0.5 Hz head roll tilt was used as another stimulus that also induced torsional ocular movements. The forces induced on the vestibular apparatus, and phases of ocular torsion against the stimulus were calculated from the observed data.
In the Coriolis stimulation during rightward yaw rotation, a rightward ocular torsion of 4.8° on average, was observed when the head pitched forward, and the direction of ocular torsion reversed when the head pitched backward. During leftward yaw rotation, these relationships were reversed with an average amplitude of 4.7° The phase of ocular torsion preceded that of Coriolis force by 0.2 s during rightward rotation and 0.14 s during leftward rotation. There were no significant differences in amplitude or phase between the directions of rotation. The phase lead of 0.5 Hz roll-tilt was significantly smaller than that of Coriolis stimulation (p < 0.01).
Coriolis stimulation induced a specific pattern of ocular torsion, where its direction and phase suggested that the mechanism likely involved both the otolith and semicircular canals. Further studies may provide a clue to the magnitude of the otolith and semicircular canal contributions.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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