Scleral Shell Prostheses – Restoring Eyes Without Removal
Scleral Shell Prostheses
Scleral Shell Prostheses – Restoring Eyes Without Removal
“When the eye remains but its function and form are lost, the scleral shell steps in—not to replace, but to refine, protect, and dignify.”
Introduction
Not all patients with a disfigured or blind eye require surgical removal. In many cases—especially in phthisis bulbi, microphthalmia, post-traumatic distortion, or non-seeing painful eyes—the globe may be intact but shrunken, opaque, or cosmetically unacceptable. For such patients, a scleral shell prosthesis offers a compassionate, non-surgical alternative.
7.1 What Is a Scleral Shell?
A scleral shell prosthesis is a thin, curved, custom-made ocular prosthesis designed to be worn over a disfigured or small existing globe. It serves cosmetic, protective, and psychological functions.
Characteristic
Full Artificial Eye
Scleral Shell Prosthesis
Indication
Post-enucleation/evisceration
Disfigured or non-seeing eye
Size
Full-thickness acrylic
Thin, shell-like curvature
Fit
Socket cavity
Over intact globe
7.2 Indications for Scleral Shell Use
Phthisis bulbi: Shrunken, non-functional globe
Microphthalmia: Developmentally small eye
Corneal opacity: Disfiguring white scar or leucoma
Post-trauma: Cosmetic deformities after injury
Post-surgical: Irregular globe following surgeries (e.g., glaucoma drainage implants)
Cosmetic correction: For psychosocial confidence without surgery
Pediatric cases: When parents opt for non-surgical rehabilitation
7.3 Classification of Scleral Shells by Thickness
Type
Indication
Thickness Range
Thin Shell (2–3 mm)
Small eye with good lid closure
Comfortable, natural
Medium Shell (3–4 mm)
Mildly protruding or irregular eye
Moderate coverage
Thick Shell (5–6 mm)
Prominent globe or need for volume increase
Often with added tinting
The ocularist decides thickness based on:
Lid position
Globe size
Motility
Socket tolerance
7.4 Fabrication Process
The creation of a scleral shell follows the same steps as a full prosthesis (see Chapter 6), but with special considerations:
Impression taking is gentler to avoid damaging sensitive or scarred globes.
Shell curvature must follow the topography of the existing globe.
Edge design ensures tear flow and minimizes lid irritation.
Thickness customization helps simulate normal eye projection.
A clear conformer may be trialed first to assess tolerance and motility.
7.5 Cosmetic and Functional Advantages
Non-surgical
Preserves the existing globe
Improves symmetry
Protects the disfigured eye
Reduces photophobia in opaque or leukomatous corneas
Enhances confidence in social situations
Especially in children and elderly patients, avoiding surgery offers both emotional and medical benefits.
7.6 Challenges and Considerations
Socket discharge due to poor tear exchange under the shell
Shell dislodgement in cases of severe lid laxity
Difficulty fitting in highly irregular globes
Risk of corneal abrasion in eyes with residual sensitivity
Management:
Use of lubricants or viscous artificial tears
Regular polishing and hygiene
Patient education about gentle insertion/removal
Custom shell edge contouring for improved comfort
7.7 Case Scenarios
Case 1: Phthisis Bulbi in a Young Woman
Post-traumatic eye with corneal scarring and hypotony
Shell prosthesis restored symmetry and allowed natural blinking
Reported major improvement in confidence and social interactions
Case 2: Microphthalmia in a 3-Year-Old Boy
Serial shell expansion used to stimulate orbital growth
Adjusted every 6 months during early childhood
Avoided need for surgery while achieving age-appropriate symmetry
Case 3: Post-Keratoplasty Disfigurement
Central scarring despite graft success
Scleral shell with neutral pupil and hand-painted iris allowed the patient to attend public events without self-consciousness.
Since last 10 years I have started fitting with Oxygen permeablwe materials like Boston or Contamac instead of PMMA for Keratoplasty patients or patients with sensitive cornea.
7.8 Tips for Successful Shell Fitting
Always perform a trial shell first before final fabrication.
Ensure no mechanical irritation from the shell edges.
Use NaFl to evaluate the fitting, corneal clearance edge and tear exchange etc.
Match iris size and scleral color precisely to the fellow eye.
Normally we advise to wear it continuously without removing for weeks toghether, but do educate the patient to remove shell every night if needed.
Use mirror or mobile camera aids to help with self-insertion at home.
If cornea is sensitive and you want to use PMMA material to design you scleral shell, then its advised to get conjuctivoplasty done (Gunderson Flap) to reduce the cornea sensitivity and successful long term wear.
7.9 Pediatric Considerations
Start fitting by 6–12 months of age in microphthalmia cases.
Encourage regular follow-up to monitor facial growth.
Provide age-appropriate support materials (storybooks, videos).
Involve school staff to build confidence in young patients.
Conclusion
Scleral shell prostheses offer an elegant solution for patients who retain a structurally abnormal or non-functional eye. Whether for a child with microphthalmia, an adult with trauma-induced phthisis, or anyone seeking dignity without surgery, the shell bridges the gap between anatomy and aesthetics, biology and beauty.