Ophthalmic Dose Compliance Monitor Team Members: Arinne Lyman – Leader Anita Zarebi – Communicator Becky Koszalinski – BSAC Michael Alexander – BWIG Client: Christopher Murphy DVM, PhD Advisor: Professor Wally Block

Presentation Outline Problem Statement Background Information Current Devices Design Constraints Alternative Designs Future Work

Problem Statement Patient Compliance Follow Doctor’s Orders? Follow Doctor’s Orders? Ophthalmic Dose Compliance Monitor Record Date and Time Record Date and Time Blinded Study Blinded Study Test Hypotheses Test Hypotheses

Background Information Interviews with Patients Calculate Number of Missed Doses Spacing Between Doses Important Norell et al. Medication Monitor Kass et al. Current Device

Current Device 2 Compartments Hidden Circuitry 15 min Counter 2 conditions: - Cap off - Inversion Electrical Interface Most recent device in literature (1984)

Design Constraints Circuitry and sensors on periphery Small, lightweight, invisible, sterile Optimally disposable (<$5/bottle) Interface with computer (wireless??) Works for different sized bottles Quality control mechanism

Suggested Materials Power Source Microprocessing IC chip Circuit Design Connects Sensors Circuit Design Connects Sensors Records Date and Time Records Date and TimeGyroscope Orientation Orientation Tactile Sensor Pressure Applied Pressure Applied Simple Wire Cap Sensor Cap – On or Off? Cap – On or Off?

Design 1: Power Source Button Cell - for use in small form projects Lithium Battery Cells Lithium Battery Cells Lasts Longer than Alkaline Small Form Factor More Expensive Alkaline Battery Cells Alkaline Battery Cells Proven Technology Inexpensive Loses Charge Faster Photo courtesy of Sanyo; design courtesy of Panasonic

Design 1: PIC Microcontroller Microprocessor as the “brain” of the chip Microprocessor as the “brain” of the chip Timer for date and time stamp Timer for date and time stamp Integrates and Interprets data from sensors Integrates and Interprets data from sensors Algorithm—successful application of medication? Algorithm—successful application of medication? Memory to store event Memory to store event time stamp

Design 1: Pros & Cons Advantages Inexpensive Inexpensive Low Power Consumption Low Power ConsumptionDisadvantages Form-factor Form-factor Inexperience with successful Inexperience with successful implementation implementation

Design 2: Gyro Sensor Micro-machined sensing element Highly sensitive Responds to forces induced by rotation Forces proportional to angular rate of rotation

Design 2: Gyro Sensor ASIC-- Application Specific Integrated Circuit Forces act on differential capacitor Detected and amplified by ASIC ASIC packaged with sensing element

Coriolis Forces Forces induced on Earth due to rotation Forces induced on bottle when inverting Set input axis of measurement For medicinal applications, choose Z-axis

Design 2: Pros & Cons Pros Easily concealed Easily concealed Reported low cost Reported low cost Sensitive SensitiveCons Difficulty with manufacturers Difficulty with manufacturers Incorporate into microprocessor Incorporate into microprocessor

Design 3: Sensor Circuits Tactile Sensor Pressure connects circuit Pressure connects circuit Simple design Simple design Inexpensive Inexpensive Concealed by label Concealed by label

Design 3: Sensor Circuits Cap Sensor Registers when cap off Registers when cap off Simple design Simple design Inexpensive Inexpensive Thin wire hardly visible Thin wire hardly visible

Design 3: Pros & Cons Pros Cheap Cheap Effective in conjuction Effective in conjuction Simple circuits Simple circuitsCons Misinterpretation of data Misinterpretation of data Incorporate in circuit design Incorporate in circuit design Bulk Bulk

Future Work Decide on manufacturers Order Parts Develop Testing Protocols Implement Testing Protocols Develop Integrated Design Build Breadboard of Design Test Integrated Design Incorporate design onto bottle Consider Miniaturization

References ACR Data Logger Bergman AB, Werner RJ. Failure of children to receive penicillin by mouth. New Engl. J. Med , Cadex Electronics Inc Kass MA, Meltzer DW, Gordon M. A Miniature Compliance Monitor for Eyedrop Medication. Arch Ophthalmol , Microchip Microsensors Norell SE, Granstrom PA, Wassen R. A medication monitor and fluorescein technique designed to study medication behavior. Acta Ophthalmol , Reynolds Electronics Smart Button Tactile Sensors Tactilus Free Form Sensors. Wikimedia Commons Yee RD, Hahn PM, Christensen RE. Medication monitor for ophthalmology. Am J Ophthalmol ,

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