Transcript Title: What do you think, everyone?

Abstract
Many people, especially elderly individuals, have
afflictions such as tremors, loss of dexterity, arthritis,
and Multiple Sclerosis, which inhibit their ability to
administer eye drops. As a result, these people may
exert too much force on the medication bottle and
streaming can occur. Streaming wastes the
medication and leads to an increase in healthcare
cost. Consequently, it is desirable to develop a device
to prevent streaming and allow the patient to
accurately administer a single drop of medication into
the eye with ease, safety, and comfort. Such a device
was constructed by incorporating two curved paddles
to squeeze the bottle, a conical eyepiece for position
accuracy, and an adjustable screw to act as a stopper
and prevent over squeezing.
Our Client – Lynn Buhmann
• Nurse practitioner at Wausau Clinics
• Deals with patients of glaucoma,
Parkinson’s, Multiple Sclerosis,
Rheumatoid arthritis, and tremors
• Patients are typically elderly and live
independently
Common Eye Diseases
• Glaucoma: Increased
pressure within the eyeball
• Macular degeneration:
Gradual loss of vision
• Cataracts: Opacity of the
lens
Motivation
• Difficulty delivering eye drops due to
– Tremors
– General loss of dexterity
• Because of these etiologies
– Medication is wasted
– Patient costs are increased
• Many patients suffer from multiple
diseases and need several medications
daily
Problem Statement
• To develop an eye drop device that can
– Administer one drop of medication
– Assist the user in placing the eye drop into the eye
– Accommodate different types of medications (different
bottle sizes)
– Conserve medication to reduce cost
Patented Eye Droppers
• Illuminated tips (US Patent, 5,584,823)
• Attachments to prevent the bottle from touching
the eye (US Patent, 5,059,188)
• Alignment glasses (US Patent, 5,255,024)
Alignment Glasses
Patented Devices
Advantages
Disadvantages
• Most patents guide the eye • No mechanism to prevent
in the administration
streaming
process
• No assistance in
• Some patents ensure that
squeezing the bottle
the bottle does not touch
• No attempt at saving
the eye
medication (cost)
Marketed Devices: ™AutoDrop
• Bottle inserted into
device
• Device rests over eye
to assist patient in
eye drop placement
• Does not control the
quantity of drops
administered
Marketed Devices: ™Autosqueeze
• Dropper bottle slides
into device
• Does not control the
amount of medication
administered
• Does not prevent
streaming
Design Specifications
•
•
•
•
•
•
•
•
•
Controls the number of drops
Easy to squeeze
Accommodates several bottle sizes
Durable
Inexpensive
Simple design
Easy to clean
Maintain sterility of medication
Ergonomically correct device
Construction
• Purchased parts from US Plastics and
Cole-Parmer
• Shaped and assembled all parts in the
engineering machine shop
• Glued together
Prototype: Features
•
•
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Polypropylene; acrylic; nylon
Cost: < $15.00
Adjustable screw-turning mechanism
Etched bottom of the cone fits most eyes
– Cushioned for additional comfort
• Bored-out portion on the side allows
bottles to slide into the device
Advantages
• When properly calibrated, consistently delivers
one drop
• Requires minimal muscle control from the user
• Improves accuracy of drop placement
• Prevents streaming of medication
Disadvantages
•
•
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Some calibration is necessary as the bottle
empties
Fails to accommodate a large variety of
bottles, such as small or narrow bottles
Not aesthetically pleasing
Testing in Progress
Testing/Calibration
• Purchased four common shapes of eye drop bottles,
each 15 mL
• Tested each bottle at a certain screw setting until no
drops could come out
• Rotated the screw until a single drop could be emitted
again
• This process was repeated until the bottle was empty
• Data were normalized by dividing the number of drops at
a certain screw setting by the total number of drops of
that bottle
number of drops at screw setting
total drops
Calibration Curve
Future Work
• Construction of a better prototype
– Incorporate a larger variety of bottles
– Require less calibration
– More aesthetically pleasing
• Research plastic molding techniques
• Research different materials
Acknowledgements
• Thanks to:
– Professor Tompkins
– Lynn Buhmann
References
• Buhmann, L. Personal Interview. January 30,
2004
• Glaucoma Research Foundation. “What is
glaucoma?” Accessed: January 20, 2004. URL:
http://www.glaucoma.org
• Lal, A. 1993. Drop volume of commercial antiglaucoma eye drops. Indian Journal of
Pharmocology. 25: 163-4.
• US Patent, 5,059,188
• US Patent, 5,255,024.
• US Patent, 5,584,823.