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Trial record 2 of 2 for:    "Astigmatism" | "Antiemetics"

Early Changes Between Lenticule Extraction and Small-Incision Lenticule Extraction

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ClinicalTrials.gov Identifier: NCT02540785
Recruitment Status : Completed
First Posted : September 4, 2015
Last Update Posted : November 28, 2016
Sponsor:
Information provided by (Responsible Party):
Xingwu Zhong, MD PhD, Sun Yat-sen University

Brief Summary:
The aim is to evaluate the short-term changes in ocular surface measures and tear inflammatory mediators after lenticule extraction (FLEx) and small-incision lenticule extraction (SMILE) procedures.

Condition or disease Intervention/treatment Phase
Myopia Astigmatism Procedure: lenticule extraction Procedure: small-incision lenticule extraction Not Applicable

Detailed Description:

The use of femtosecond (FS) laser has become one of the most significant technological advancements in refractive surgery. A breakthrough FS laser-assisted myopic and myopic astigmatic correction procedure can now be performed using a prototype femtosecond system. This first all-in-one FS-laser system was designed to perform the refractive lenticule extraction (ReLEx) procedures, femtosecond lenticule extraction (FLEx) and small-incision lenticule extraction (SMILE). In FLEx, a corneal flap is created by the FS laser (similar to LASIK) and lifted, allowing lenticule removal. For SMILE, a truly without flap procedure, only a small—2-4mm— incision is made, through which the lenticule is removed.

Ocular surface disruption during corneal refractive surgery is commonly considered to be closely related to the development of dry eye. Multiple etiologies contribute to this ocular surface disruption, including the flap creation and stromal ablation involved in previous refractive surgery techniques. Corneal nerve damage has been considered the main cause of dry eye, due to disrupted afferent sensory nerves, reduced blink reflex, and increased tear evaporation leading to tear film instability. In addition, postoperative inflammatory mediator fluctuations are also a key factor related to ocular surface damage. Extensive research has described the effects of cytokines, chemokines and growth factors in modulating corneal wound healing, cell migration, and apoptosis on the ocular surface after refractive surgery.

For both FLEx and SMILE, stromal ablation has been replaced by refractive lenticule removal. In terms of corneal flap formation, FLEx still requires an epithelial-stromal flap, while SMILE employs only a small incision to extract the lenticule. Hence, the investigators hypothesize that SMILE will have less effect on patients' ocular surface markers and inflammatory mediators, compared to FLEx. In support of this hypothesis, previous studies have reported that more damage to the sub-basal nerve plexus of the cornea and more changes in ocular surface evaluations were found after FLEx than after SMILE. In this study, the investigators have focused on postoperative changes to tear inflammatory mediators and the relationship of FLEx and SMILE to dry eye.


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Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 41 participants
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)
Primary Purpose: Treatment
Official Title: Comparison of Early Changes in Ocular Surface and Inflammatory Mediators Between Lenticule Extraction and Small-Incision Lenticule Extraction
Study Start Date : April 2014
Actual Primary Completion Date : December 2014
Actual Study Completion Date : December 2014

Resource links provided by the National Library of Medicine


Arm Intervention/treatment
Experimental: lenticule extraction
The patients in this group chose to receive the lenticule extraction surgery.
Procedure: lenticule extraction
Four femtosecond incisions were created in succession: the posterior surface of the refractive lenticule (spiral in), the lenticule border, the anterior surface of the refractive lenticule (spiral out), and the corneal flap in the superior region. After the suction was released, the flap was opened using a thin, blunt spatula and the free refractive lenticule was subsequently grasped with a forceps and extracted, after which the flap was repositioned carefully
Other Names:
  • 0.3% tobramycin/dexamethasone (TobraDex, Alcon)
  • 0.5% levofloxacin (Cravit, Santen)
  • sodium hyaluronate (HYCOSAN,URSAPHARM Arzneimittel GmbH)

Experimental: small-incision lenticule extraction
The patients in this group chose to receive the small-incision lenticule extraction surgery.
Procedure: small-incision lenticule extraction
Four femtosecond incisions were created in succession: the posterior surface of the refractive lenticule (spiral in), the lenticule border, the anterior surface of the refractive lenticule (spiral out), make a small incision
Other Names:
  • 0.3% tobramycin/dexamethasone (TobraDex, Alcon)
  • 0.5% levofloxacin (Cravit, Santen)
  • sodium hyaluronate (HYCOSAN,URSAPHARM Arzneimittel GmbH)




Primary Outcome Measures :
  1. scale of Schirmer I test [ Time Frame: up to 1month after surgery ]
  2. scale of corneal fluorescein staining [ Time Frame: up to 1month after surgery ]
  3. scale of noninvasive tear breakup time [ Time Frame: up to 1month after surgery ]
  4. questionnaire of ocular surface disease index [ Time Frame: up to 1month after surgery ]
  5. scale of central corneal sensitivity [ Time Frame: up to 1month after surgery ]
  6. scale of tear meniscus height [ Time Frame: up to 1month after surgery ]
  7. concentration of Interleukin-1α [ Time Frame: up to 1month after surgery ]
  8. concentration of tumor necrosis factor-α [ Time Frame: up to 1month after surgery ]
  9. concentration of nerve growth factor [ Time Frame: up to 1month after surgery ]
  10. concentration of interferon-γ [ Time Frame: up to 1month after surgery ]
  11. concentration of transforming growth factor-β1 [ Time Frame: up to 1month after surgery ]
  12. concentration of matrix metalloproteinase-9 [ Time Frame: up to 1month after surgery ]

Secondary Outcome Measures :
  1. Correlation Between Inflammatory Mediators and Ocular Surface Changes [ Time Frame: up to 1month after surgery ]


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Ages Eligible for Study:   18 Years to 25 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes
Criteria

Inclusion Criteria:

  • minimum age of 18 years(range from 18 year to 25 years); corneal thickness 500 μm with calculated residual stromal bed after treatment greater than 300 μm; preoperative spherical equivalent refraction between
  • 2.00 diopter (D) and -6.50 D; preoperative cylindrical equivalent refraction between -0.25 D and -1.50 D; preoperative corneal curvature from 41.0 D to 46.0 D with a regular topographic pattern, verified with an Atlas topographer; monocular best corrected visual acuity of 20/20 or better and stable refractive error (less than 0.5 D change) for 24 months before surgery

Exclusion Criteria:

  • systemic disease that contraindicated the surgery (such as diabetes, glaucoma and systemic collagen vascular disease); corneal abnormality or disease; a history of tear supplement usage or contact lens wear during the past year

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT02540785


Sponsors and Collaborators
Sun Yat-sen University
Investigators
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Principal Investigator: Xingwu Zhong, MD PhD Zhongshan Ophthalmic Center, Sun Yat-sen University

Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
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Responsible Party: Xingwu Zhong, MD PhD, Professor, Sun Yat-sen University
ClinicalTrials.gov Identifier: NCT02540785     History of Changes
Other Study ID Numbers: 2014-005
First Posted: September 4, 2015    Key Record Dates
Last Update Posted: November 28, 2016
Last Verified: November 2016
Keywords provided by Xingwu Zhong, MD PhD, Sun Yat-sen University:
Refractive Surgical Procedures
small-incision lenticule extraction
lenticule extraction
inflammatory mediators
Additional relevant MeSH terms:
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Astigmatism
Antiemetics
Surgical Wound
Refractive Errors
Eye Diseases
Wounds and Injuries
Levofloxacin
Ofloxacin
Tobramycin
Tobramycin, Dexamethasone Drug Combination
Dexamethasone
Dexamethasone acetate
BB 1101
Hyaluronic Acid
Anti-Inflammatory Agents
Autonomic Agents
Peripheral Nervous System Agents
Physiological Effects of Drugs
Gastrointestinal Agents
Glucocorticoids
Hormones
Hormones, Hormone Substitutes, and Hormone Antagonists
Antineoplastic Agents, Hormonal
Antineoplastic Agents
Protease Inhibitors
Enzyme Inhibitors
Molecular Mechanisms of Pharmacological Action
Anti-Infective Agents, Urinary
Anti-Infective Agents
Renal Agents