Mechanical modifications of soft actuators for the use as a dynamic iris implant

Abstract

Aniridia is a condition characterized by defects or absence of the iris. Since the eyes are a central point of attention in the human face, these deformities are often covered with cosmetic implants. However, patients suffer from the static pupil diameter of these implants, resulting in high light sensitivity or inadequate night vision. Therefore, we present a functional iris implant based on dielectric elastomer actuators. These electric drives are characterized by a silent and continuous adaptation as well as a small construction volume and a low heat emission. Since they normally exhibit in-plane uniaxial motion, this displacement must be focused to operate similarly to the iris sphincter. Therefore, we investigated possible mechanical modifications of the setups to generate a directional motion. The results of the study are presented and discussed.Clinical Relevance-The proposed system design enables the functional treatment of aniridia and other accidental iris defects. In addition, the system serves as a basis for later developments of e.g. functional lenses that allow focus adjustment.

Aerosol‐Jet Printed Sensors for Environmental, Safety, and Health Monitoring: A Review

“…For instance, AJP has recently been employed for the creation of complex multicellular environments analogous to extracellular matrices for tissue engineering and drug screening; [ 197 ] the printing of biological inks toward creating cost‐effective in vitro diagnostic assays; [ 27 ] the fabrication of handmade medical devices, such as cost‐effective cochlear implants, for improved quality of life; the early diagnosis and management of medical conditions including diabetes, [ 104 ] cancers, [ 222 ] and hematological disorders [ 56 ] through low‐cost, disposable point‐of‐care devices; the construction of creative interventions such as cardiac repair patches following myocardial injuries [ 71 ] and the replication of corneal tissue for implants following injuries, disease, and congenital disabilities; [ 198 ] as well as for the development of high sensitivity perovskite photodetectors to reduce the health hazards related to strongly ionizing X‐ray photons in medical imaging. [ 74 ] In addition, progress in biocompatible materials paves the way for the development of unique wearable AJP‐based devices, including artificial muscles toward dynamic iris implants [ 207 ] and on‐body sensors that regulate body temperature and monitor health and motion, [ 208,209 ] which could ultimately benefit applications related to prosthetics and healthcare. Moreover, advancements in the integration of AJP for flexible and stretchable platforms promote the development of complex and dynamic structures as sensors that can conform to the surfaces found in soft robotics applications.…”

“…AJP has been applied to the construction of soft, elastomericbased DEAs since 2013 [206] toward the development of prosthesis [207] and conformal wearables. [208,209] Actuators composed of a stacked layer of printed silicon (Wacker Elastosil P 7670) and printed with reduced graphene oxide (rGO) electrodes that can withstand maximum elongation of up to 100% have been reported by Reitelshöfer et al [210,211] Following this approach, recently Martin et al reported the application of printed DEAs as a functional iris implant that allows focus adjustments with respect to changes in surrounding light conditions.…”

“…[208,209] Actuators composed of a stacked layer of printed silicon (Wacker Elastosil P 7670) and printed with reduced graphene oxide (rGO) electrodes that can withstand maximum elongation of up to 100% have been reported by Reitelshöfer et al [210,211] Following this approach, recently Martin et al reported the application of printed DEAs as a functional iris implant that allows focus adjustments with respect to changes in surrounding light conditions. [207] In addition, actuators designed using a similar approach and based on stacked medical grade silicones for applications in healthcare as on-body motion sensors were also presented by Martin et al [208,209] Although much work remains in the area of AJP-based actuators, these advancements offer promise toward healthcare solutions where the high energy density and highly dynamic kinematics of DEAs may successfully be applied to conformal wearables and prosthesis. Considering healthcare applications, AJP has also been utilized for mobile eye therapies, [97] cochlear implants, [90] and implantable biosystems.…”

“…AJP has been applied to the construction of soft, elastomeric‐based DEAs since 2013 [ 206 ] toward the development of prosthesis [ 207 ] and conformal wearables. [ 208,209 ] Actuators composed of a stacked layer of printed silicon (Wacker Elastosil P 7670) and printed with reduced graphene oxide (rGO) electrodes that can withstand maximum elongation of up to 100% have been reported by Reitelshöfer et al.…”

“…reported the application of printed DEAs as a functional iris implant that allows focus adjustments with respect to changes in surrounding light conditions. [ 207 ] In addition, actuators designed using a similar approach and based on stacked medical grade silicones for applications in healthcare as on‐body motion sensors were also presented by Martin et al. [ 208,209 ] Although much work remains in the area of AJP‐based actuators, these advancements offer promise toward healthcare solutions where the high energy density and highly dynamic kinematics of DEAs may successfully be applied to conformal wearables and prosthesis.…”