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The Molteno M-Sphere

D R Jordan1, I Hwang, S Brownstein

  • 1Department of Ophthalmology, University of Ottawa Eye Institute, Ontario, Canada.

Ophthalmic Plastic and Reconstructive Surgery
|October 6, 2000
PubMed
Abstract

Insights

The Molteno M-Sphere, a hydroxyapatite (HA) implant, offers central fibrovascularization within 4 weeks in rabbits. However, its lightweight nature makes it fragile and requires careful handling.

Area of Science:

  • Biomaterials Science
  • Ophthalmology
  • Surgical Implants

Background:

  • Hydroxyapatite (HA) implants are used in ophthalmic reconstructive surgery.
  • The Molteno M-Sphere is a recently FDA-approved HA implant.

Purpose of the Study:

  • To analyze the physical, chemical, and biological properties of the Molteno M-Sphere HA implant.
  • To evaluate its potential for fibrovascularization and compare its characteristics to other HA implants.

Main Methods:

  • Macroscopic, chemical (XRD, XRF), and microscopic (SEM) analysis of the implant.
  • Animal implantation in New Zealand albino rabbits.
  • Evaluation of vascularization using MRI and histopathology.

Main Results:

  • The M-Sphere is a lightweight, pure HA implant with interconnected pores (300-600 microm).
  • MRI showed central enhancement by 4 weeks; histopathology confirmed uniform fibrovascularization.
  • The implant is fragile compared to other HA implants, necessitating careful handling.

Conclusions:

  • The M-Sphere is a viable HA implant option for ophthalmic reconstruction, promoting early central vascularization.
  • Its porous structure facilitates fibrovascular ingrowth.
  • Implant fragility is a key consideration, requiring meticulous handling during surgical procedures.

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