Limits...
Customized epithelial debridement for thin ectatic corneas undergoing corneal cross-linking: epithelial island cross-linking technique.

Mazzotta C, Ramovecchi V - Clin Ophthalmol (2014)

Bottom Line: Thin corneas with a minimum corneal thickness less than 400 μm after epithelial removal represent a contraindication to standard epithelium-off cross-linking (CXL) treatment due to a significant endothelial cell density decrease and potentiality of permanent haze development.However the iatrogenic swelling effect might not be durable throughout the CXL procedure increasing the risk of postoperative complications.According to our clinical and in-vivo micro-morphological results the technique results safe, and efficacious in stabilizing progressive keratoconus and may be considered a valid option in the treatment of thin ectatic corneas alone or in combination with hypoosmolar or dextran-free riboflavin solutions.

View Article: PubMed Central - PubMed

Affiliation: Unità Operativa Complessa di Oculistica, Siena University Hospital, Siena, Italy.

ABSTRACT
Thin corneas with a minimum corneal thickness less than 400 μm after epithelial removal represent a contraindication to standard epithelium-off cross-linking (CXL) treatment due to a significant endothelial cell density decrease and potentiality of permanent haze development. Preoperative swelling of the cornea with hypoosmolar riboflavin solutions broadens the spectrum of CXL indications to thin corneas. However the iatrogenic swelling effect might not be durable throughout the CXL procedure increasing the risk of postoperative complications. The transepithelial CXL technique proposed for thin corneas demonstrated poor clinical results and mid- to long-term keratoconus instability. The epithelial island CXL technique with customized pachymetry-guided epithelial debridement was evaluated by means of in vivo laser scanning confocal microscopy, corneal topography, and clinical examination in a 1-year follow-up, in order to assess if it may be considered an alternative surgical option for keratoconic patients with thin corneas undergoing corneal collagen CXL. According to our clinical and in-vivo micro-morphological results the technique results safe, and efficacious in stabilizing progressive keratoconus and may be considered a valid option in the treatment of thin ectatic corneas alone or in combination with hypoosmolar or dextran-free riboflavin solutions.

No MeSH data available.


Related in: MedlinePlus

In vivo scanning laser confocal microscopy after epithelial island cross-linking in thin corneas under 400 μm.Notes: Red arrows indicate keratocytes apoptosis’ and a demarcation line at a depth between 130 and 180 μm (mean 160 μm) under the epithelial island thinnest point location. White arrows indicate lacunar corneal edema associated with keratocytes’ apoptotic bodies. The blue arrow shows the deep demarcation line at 272 μm in the epithelium-off paracentral area.Abbreviations: Epi-on, epithelium-on; Epi-off, epithelium-off.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4109632&req=5

f3-opth-8-1337: In vivo scanning laser confocal microscopy after epithelial island cross-linking in thin corneas under 400 μm.Notes: Red arrows indicate keratocytes apoptosis’ and a demarcation line at a depth between 130 and 180 μm (mean 160 μm) under the epithelial island thinnest point location. White arrows indicate lacunar corneal edema associated with keratocytes’ apoptotic bodies. The blue arrow shows the deep demarcation line at 272 μm in the epithelium-off paracentral area.Abbreviations: Epi-on, epithelium-on; Epi-off, epithelium-off.

Mentions: Early post-operative days were comfortable for all treated patients. Therapeutic soft contact lenses were removed after 3 days without epithelial defects or delayed re-epithelialization. In vivo laser scanning confocal microscopic (IVCM) analysis performed 1 month after treatment (Figure 3), revealed keratocytes’ apoptosis associated with nerve fibers’ loss and lacunar edema under the epithelial island at an average depth of 160 μm (range 130–180 μm); keratocytes’ apoptosis in the paracentral and de-epithelialized ring was recorded at 250 μm depth on average (230–270 μm). No change in keratocytes’ density was detected in the peripheral area with epithelium in situ. Preoperative endothelial cell density was 2,451 cells/mm2 on average (range 2,092–3,016 cells/mm2). No microstructural adverse events were recorded at the endothelial layer during the follow-up and the final endothelial cells’ count was 2,456 cells/mm2 (range 2,062–3,012 cells/mm2).


Customized epithelial debridement for thin ectatic corneas undergoing corneal cross-linking: epithelial island cross-linking technique.

Mazzotta C, Ramovecchi V - Clin Ophthalmol (2014)

In vivo scanning laser confocal microscopy after epithelial island cross-linking in thin corneas under 400 μm.Notes: Red arrows indicate keratocytes apoptosis’ and a demarcation line at a depth between 130 and 180 μm (mean 160 μm) under the epithelial island thinnest point location. White arrows indicate lacunar corneal edema associated with keratocytes’ apoptotic bodies. The blue arrow shows the deep demarcation line at 272 μm in the epithelium-off paracentral area.Abbreviations: Epi-on, epithelium-on; Epi-off, epithelium-off.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4109632&req=5

f3-opth-8-1337: In vivo scanning laser confocal microscopy after epithelial island cross-linking in thin corneas under 400 μm.Notes: Red arrows indicate keratocytes apoptosis’ and a demarcation line at a depth between 130 and 180 μm (mean 160 μm) under the epithelial island thinnest point location. White arrows indicate lacunar corneal edema associated with keratocytes’ apoptotic bodies. The blue arrow shows the deep demarcation line at 272 μm in the epithelium-off paracentral area.Abbreviations: Epi-on, epithelium-on; Epi-off, epithelium-off.
Mentions: Early post-operative days were comfortable for all treated patients. Therapeutic soft contact lenses were removed after 3 days without epithelial defects or delayed re-epithelialization. In vivo laser scanning confocal microscopic (IVCM) analysis performed 1 month after treatment (Figure 3), revealed keratocytes’ apoptosis associated with nerve fibers’ loss and lacunar edema under the epithelial island at an average depth of 160 μm (range 130–180 μm); keratocytes’ apoptosis in the paracentral and de-epithelialized ring was recorded at 250 μm depth on average (230–270 μm). No change in keratocytes’ density was detected in the peripheral area with epithelium in situ. Preoperative endothelial cell density was 2,451 cells/mm2 on average (range 2,092–3,016 cells/mm2). No microstructural adverse events were recorded at the endothelial layer during the follow-up and the final endothelial cells’ count was 2,456 cells/mm2 (range 2,062–3,012 cells/mm2).

Bottom Line: Thin corneas with a minimum corneal thickness less than 400 μm after epithelial removal represent a contraindication to standard epithelium-off cross-linking (CXL) treatment due to a significant endothelial cell density decrease and potentiality of permanent haze development.However the iatrogenic swelling effect might not be durable throughout the CXL procedure increasing the risk of postoperative complications.According to our clinical and in-vivo micro-morphological results the technique results safe, and efficacious in stabilizing progressive keratoconus and may be considered a valid option in the treatment of thin ectatic corneas alone or in combination with hypoosmolar or dextran-free riboflavin solutions.

View Article: PubMed Central - PubMed

Affiliation: Unità Operativa Complessa di Oculistica, Siena University Hospital, Siena, Italy.

ABSTRACT
Thin corneas with a minimum corneal thickness less than 400 μm after epithelial removal represent a contraindication to standard epithelium-off cross-linking (CXL) treatment due to a significant endothelial cell density decrease and potentiality of permanent haze development. Preoperative swelling of the cornea with hypoosmolar riboflavin solutions broadens the spectrum of CXL indications to thin corneas. However the iatrogenic swelling effect might not be durable throughout the CXL procedure increasing the risk of postoperative complications. The transepithelial CXL technique proposed for thin corneas demonstrated poor clinical results and mid- to long-term keratoconus instability. The epithelial island CXL technique with customized pachymetry-guided epithelial debridement was evaluated by means of in vivo laser scanning confocal microscopy, corneal topography, and clinical examination in a 1-year follow-up, in order to assess if it may be considered an alternative surgical option for keratoconic patients with thin corneas undergoing corneal collagen CXL. According to our clinical and in-vivo micro-morphological results the technique results safe, and efficacious in stabilizing progressive keratoconus and may be considered a valid option in the treatment of thin ectatic corneas alone or in combination with hypoosmolar or dextran-free riboflavin solutions.

No MeSH data available.


Related in: MedlinePlus