In Vivo Inspection of the Olfactory Epithelium: Feasibility of Robotized Optical Biopsy

Abstract

Inspecting the olfactory cleft can be of high interest, as it is an open access to neurons, and thus an opportunity to collect in situ related data in a non-invasive way. Also, recent studies show a strong link between olfactory deficiency and neurodegenerative diseases such as Alzheimer and Parkinson diseases. However, no inspection of this area is possible today, as it is very difficult to access. Only robot-assisted interventions seem viable to provide the required dexterity. The feasibility of this approach is demonstrated in this article, which shows that the path complexity to the olfactory cleft can be managed with a concentric tube robot (CTR), a particular type of continuum robot. First, new anatomical data are elaborated, in particular for the olfactory cleft, that remains hardly characterized. 3D reconstructions are conducted on the database of 20 subjects, using CT scan images. Measurements are performed to describe the anatomy, including metrics with inter-subject variability. Then, the existence of collision-free passageways for CTR is shown using the 3D reconstructions. Among the 20 subjects, 19 can be inspected using only 3 different robot geometries. This constitutes an essential step towards a robotic device to inspect subjects for clinical purposes.

SLAM-Based Follow-the-Leader Deployment of Concentric Tube Robots

“…In the remaining of the paper, the CTR considered is made of an inner straight tube and two outer curved tubes, that conform to make a straight, curved, and straight links as illustrated in Fig. 2, compatible with a deployment in the nasal cavity which is the clinical motivation of this work [12].…”

“…This seems however mandatory given i) the inter-patient variability which can make hazardous CTR control based on a priori knowledge which is not patient specific, ii) the possible anatomy variations between planning and inspection phases, and iii) the existence of physiological motions such as breathing-induced motions, leading to time-varying displacements and deformations of the patient anatomy. Considering the environment of CTRs in real-time during navigation is needed, and can be well illustrated by the task of the olfactory cleft inspection, where contacts with tissues are not admissible according to the clinical requirements [12].…”

“…Safety is also considered by checking CTR stability within the controller scheme. To develop and assess this proposition, we consider a 3-tube CTR design, previously identified as relevant for navigation in the nasal cavity [12]. The tube geometries of the robot were selected for FTL deployment using a dataset of nasal cavities.…”

Comparison of Noninvasive Imagery Methods to Observe Healthy and Degenerated Olfactory Epithelium in Mice for the Early Diagnosis of Neurodegenerative Diseases

“…Recent studies have shown a strong correlation between impaired olfactory perception of patients and neurodegenerative conditions, such as Alzheimer's disease (AD) (Arnold et al, 1998;Wang et al, 2010;Wesson et al, 2010;Kjelvik et al, 2014), Parkinson's disease (Berg, 2008;Doty, 2012), frontotemporal dementia (McLaughlin and Westervelt, 2008;Alves et al, 2014), and Huntington's disease (Lazic et al, 2007;Barresi et al, 2012). These works lead to consider olfactory FIGURE 1 | Representation of nasal anatomy, structure, and the OE shape and location (Girerd et al, 2018).…”

“…It is characterized by three main cell types that can be clearly identified: the olfactory sensory neurons constituting the receptor cells for trapping odor molecules, the supporting cells and the basal stem cells that continuously regenerate olfactory neurons (Holbrook et al, 1995 ; Barrios et al, 2014 ). Reaching the OE for in vivo characterization and monitoring of the neural organization ( Figure 1 ) is still an open scientific and clinical challenge because of its location and access pathway as demonstrated in our recent work (Girerd et al, 2018 ). To the best of our knowledge, no conventional instrument can be used to non-invasively reach this area.…”