Design of a passive pressure regulating shunt valve for glaucoma filtration surgery

Michael R. Wild, R. M.V. Pidaparti, Louis B. Cantor, R. S. Moorthy

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

Present ocular drainage implants for refractory glaucoma reduce intraocular pressure by unregulated aqueous drainage often leading to postoperative hypotony. To reduce hypotony a passive pressure regulating shunt valve (PPRSV) was designed based on the single plate Molteno. The design incorporates a synthetic elastomer into a chamber within the basic Molteno structure. Aqueous pressure deforms the elastomer beneath a perforated plate to provide flow through holes to the subconjunctival space. A 10x prototype was evaluated with respect to flow rate and pressure for two different elastomers and plates. A pressure threshold of 4 mm of Hg was achieved below which no flow occurred. This threshold increased with increased elastomer stiffness. The rate of increase in flow beyond threshold was not affected by elastomer stiffness. The threshold decreased with five-holed vs one-holed plates. Above threshold five-holed plates had higher flow rates than single-holed plates. Performance was unaffected by orientation relative to gravity. The PPRSV can maintain pressure up to 4 mm of Hg and permit flow at higher pressures. The PPRSV devices may have utility as an alternative tube shunt device.

Original languageEnglish (US)
Title of host publication1992 Advances in Bioengineering
PublisherPubl by ASME
Pages553-556
Number of pages4
ISBN (Print)0791811166
StatePublished - Dec 1 1992
EventWinter Annual Meeting of the American Society of Mechanical Engineers - Anaheim, CA, USA
Duration: Nov 8 1992Nov 13 1992

Publication series

NameAmerican Society of Mechanical Engineers, Bioengineering Division (Publication) BED
Volume22

Other

OtherWinter Annual Meeting of the American Society of Mechanical Engineers
CityAnaheim, CA, USA
Period11/8/9211/13/92

Fingerprint

Surgery
Elastomers
Drainage
Stiffness
Flow rate
Perforated plates
Refractory materials
Gravitation

ASJC Scopus subject areas

  • Engineering(all)

Cite this

Wild, M. R., Pidaparti, R. M. V., Cantor, L. B., & Moorthy, R. S. (1992). Design of a passive pressure regulating shunt valve for glaucoma filtration surgery. In 1992 Advances in Bioengineering (pp. 553-556). (American Society of Mechanical Engineers, Bioengineering Division (Publication) BED; Vol. 22). Publ by ASME.

Design of a passive pressure regulating shunt valve for glaucoma filtration surgery. / Wild, Michael R.; Pidaparti, R. M.V.; Cantor, Louis B.; Moorthy, R. S.

1992 Advances in Bioengineering. Publ by ASME, 1992. p. 553-556 (American Society of Mechanical Engineers, Bioengineering Division (Publication) BED; Vol. 22).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Wild, MR, Pidaparti, RMV, Cantor, LB & Moorthy, RS 1992, Design of a passive pressure regulating shunt valve for glaucoma filtration surgery. in 1992 Advances in Bioengineering. American Society of Mechanical Engineers, Bioengineering Division (Publication) BED, vol. 22, Publ by ASME, pp. 553-556, Winter Annual Meeting of the American Society of Mechanical Engineers, Anaheim, CA, USA, 11/8/92.
Wild MR, Pidaparti RMV, Cantor LB, Moorthy RS. Design of a passive pressure regulating shunt valve for glaucoma filtration surgery. In 1992 Advances in Bioengineering. Publ by ASME. 1992. p. 553-556. (American Society of Mechanical Engineers, Bioengineering Division (Publication) BED).
Wild, Michael R. ; Pidaparti, R. M.V. ; Cantor, Louis B. ; Moorthy, R. S. / Design of a passive pressure regulating shunt valve for glaucoma filtration surgery. 1992 Advances in Bioengineering. Publ by ASME, 1992. pp. 553-556 (American Society of Mechanical Engineers, Bioengineering Division (Publication) BED).
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