An observational study in Refractive Errors, Myopia and Myopic Astigmatism, sponsored by Loay Abdulmutalib Almusawi. Completed at 1 site in Iraq. Open to participants aged 18 Years to 50 Years. Per ClinicalTrials.gov, last updated 2024-11-25.
Sponsored by Loay Abdulmutalib Almusawi · Observational
The goal of this observational study is to test whether surgeries for lenses designed to be implanted in the eye to correct refractive error can be done without the need for using viscoelastic substances that are used routinely nowadays to make it easier to introduce them inside the human eye and protect the inside of the eye during the operation.
The main question it aims to answer is that is it safe to do the surgery without using them? to answer this question researchers will access recorded data of patients that underwent refractive surgeries in a private clinic since 2017 and compare them as two groups: those who underwent the traditional procedures and those who had it without the use of dispersive viscoelastics in regard to their vision before and after surgery, their ocular pressure and biomicroscopic analysis of the inside of their corneas before and after surgery.
Records of patients that had undergone ICL implantation surgery in Al-Ferdows private eye hospital in Baghdad between 2017 and 2023 were accessed. Two groups of patients were identified, for the first group the ICL was implanted with the use of both dispersive and cohesive OVDs (traditional OVD group) and for the second one a novel method of implantation was used without utilizing dispersive OVD (reduced OVD) group. Both types of surgery were done by the same surgeon and in the same settings. The operative notes of the OVD group were as follows: under topical anesthesia if the ICL is toric, manual corneal marking is done in the sitting position using pendular marker. After loading of the ICL, two-step clear corneal main incision 2.8 mm in width with a bit long track of 1.5-2 mm to enhance its valve action was fashioned. Intracameral injection of dispersive OVD. The ICL was implanted with mouth-to-mouth technique. Anterior chamber reformation with cohesive OVD, then haptics are gently pushed behind the iris using an olive-tipped manipulator, ensuring alignment to proper axis in case of toric ICL, otherwise spherical ICL is placed directly at 180° axis. After that, AC (anterior chamber) wash with irrigation/aspiration is performed then stromal hydration was done to seal the surgical wound. In the reduced OVD group, modification to the traditional method involved omitting the step of dispersive OVD injection and instead utilizing Intracameral injection of 1:1 mixture of 1:1000 adrenaline and 2% lidocaine in an overfilling manner. All other surgical steps are performed in an identical manner.
The study was ethically approved by the institutional review committee at the respective hospital and a similar committee at the college of medicine of university of Basrah according to the local guidelines and protocols. Written informed consent was obtained from each patient before the surgery. The study followed tenets of declaration of Helsinki.
For both groups, records involving preoperative and postoperative assessments such as uncorrected and best corrected visual acuity, refractive error quantification both objectively utilizing an autorefractometer autorefractor Nidek ARK 1 (Nidek Inc, Gamagori, Japan) and subjectively as manifest refraction, clinical slit-lamp examination notes, intraocular pressure with non-contact air puff tonometer Topcon CT-1P (Topcon Inc., Tokyo, Japan), AC depth assessment by Pentacam Scheimpflug (Oculus Optikgeräte GmbH Inc., Wetzlar, Germany), specular microscopy study of corneal endothelial cells (endothelial cell density (ECD), coefficient of variation (CV) and hexagonality) using Topcon SP-1p Specular Microscope (Topcon Corporation, Tokyo, Japan), were accessed and analyzed using the latest software in SPSS. Patients with missing or incomplete data were excluded from the study. Exclusion criteria also included patients with severe ocular surface disease, unstable refraction, glaucoma, cataract, retinal detachment and uveitis. Unpaired t test or Mann-Whitney test was used to compare the two groups according to fulfilled statistical assumptions. Significance was considered at P value less than 0.05.
420 studies on the registry are indexed under Refractive Errors; 59 are open to participants now.
This study's enrollment of 448 is above the median of 150 across 108 observational studies indexed under Refractive Errors.
Browse Refractive Errors studies →This is the only study on the registry with Loay Abdulmutalib Almusawi as lead sponsor.
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Records of patients that had undergone ICL implantation surgery in Al-Ferdows private eye hospital in Baghdad between 2017 and 2023 were accessed. Two groups of patients were identified, for the first group the ICL was implanted with the use of both dispersive and cohesive OVDs (traditional OVD group) and for the second one, a novel method of implantation was used without utilizing dispersive OVD (reduced OVD) group.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
In this group of patients, the ICL was implanted utilizing both cohesive and dispersive ophthalmic viscosurgical device.
Device: phakic intraocular lens implantation traditional
In this group of patients, the ICL was implanted with the use of cohesive OVD only.
Device: phakic intraocular lens implantation reduced OVD
patients with refractive errors undergo surgical implantation of a lens inside the eye (implantable collamer lens or ICL) to correct these refractive errors. The procedure is done with help of use of both cohesive and dispersive OVD
Also known as: ICL implantation traditional, Intraocular refractive surgery
patients with refractive errors undergo surgical implantation of a lens inside the eye (implantable collamer lens or ICL) to correct these refractive errors. The procedure is done with help of use of only cohesive OVD without using dispersive OVD.
Also known as: ICL implantation reduced OVD, Intraocular refractive surgery
Unaided Visual Acuity After the Procedure
visual acuity (vision of the patient) without use of any glasses measured using LogMar charts. This measure has no specified units
Time frame: 1-2 years after the surgery
Intraocular Pressure Postoperatively
intraocular pressure in mmHg as measured by non-contact airpuff tonometer Topcon CT-1P (Topcon Inc., Tokyo, Japan). intraocular pressure is measured in millimeters of mercury
Time frame: first day, first week and first month after the procedure
Specular Microscopy Parameter: Endothelial Cell Density
defined as the number of corneal endothelial cells per square millimeter of area, measured using the automated machine from Topcon SP-1P (Topcon Inc, Tokyo, Japan)
Time frame: 1-2 years after the surgery
Specular Microscopy Parameter: Endothelial Cells Hexagonality
defined as the percentage of endothelial cells having 6 borders and shaped like a hexagon. this measure reflects the overall health of the endothelial cells and decreased hexagonality below 58-60% indicates corneal enodthelial pleomorphism, also measured using the automated machine from Topcon SP-1P (Topcon Inc, Tokyo, Japan)
Time frame: 1-2 years after the surgery
Specular Microscopy Parameter: Coefficient of Variation of Corneal Endothelial Cells
The standard deviation of the mean cell area divided by the mean cell area gives the coefficient of variation, a unitless number that is normally less than 0.30. it reflects the health of endothelial cells and measured using the automated machine from Topcon SP-1P (Topcon Inc, Tokyo, Japan).
Time frame: 1-2 years after the surgery
Postoperative Complications
such as glaucoma, cataract, persistent uveitis, macular edema, endophthalmitis..etc.
Time frame: any time post op within the maximum 2 years follow up period
Data from all patients that had undergone ICL implantation surgery for the correction of refractive errors in Al-Ferdows private eye hospital in Baghdad between 2017 and 2023 were accessed.
| Milestone | Traditional OVD Group | Reduced OVD Group |
|---|---|---|
| Started | 134 | 314 |
| Completed | 46 | 67 |
| Not completed | 88 | 247 |
| Withdrew: Missing data | 88 | 247 |
visual acuity (vision of the patient) without use of any glasses measured using LogMar charts. This measure has no specified units
| LogMar vision | Traditional OVD Group | Reduced OVD Group |
|---|---|---|
| Unaided Visual Acuity After the Procedure | 0.264 ± 0.17 | 0.227 ± 0.12 |
intraocular pressure in mmHg as measured by non-contact airpuff tonometer Topcon CT-1P (Topcon Inc., Tokyo, Japan). intraocular pressure is measured in millimeters of mercury
| mmHg | Traditional OVD Group | Reduced OVD Group |
|---|---|---|
| Intraocular Pressure Postoperatively | 17.44 ± 4.46 | 17.80 ± 4.58 |
defined as the number of corneal endothelial cells per square millimeter of area, measured using the automated machine from Topcon SP-1P (Topcon Inc, Tokyo, Japan)
| cells per square millimeter | Traditional OVD Group | Reduced OVD Group |
|---|---|---|
| Specular Microscopy Parameter: Endothelial Cell Density | 2785.4 ± 417.1 | 2851.0 ± 305.1 |
defined as the percentage of endothelial cells having 6 borders and shaped like a hexagon. this measure reflects the overall health of the endothelial cells and decreased hexagonality below 58-60% indicates corneal enodthelial pleomorphism, also measured using the automated machine from Topcon SP-1P (Topcon Inc, Tokyo, Japan)
| percentage of hexagonal cells | Traditional OVD Group | Reduced OVD Group |
|---|---|---|
| Specular Microscopy Parameter: Endothelial Cells Hexagonality | 58.69 ± 10.43 | 57.93 ± 9.26 |
The standard deviation of the mean cell area divided by the mean cell area gives the coefficient of variation, a unitless number that is normally less than 0.30. it reflects the health of endothelial cells and measured using the automated machine from Topcon SP-1P (Topcon Inc, Tokyo, Japan).
| uniteless | Traditional OVD Group | Reduced OVD Group |
|---|---|---|
| Specular Microscopy Parameter: Coefficient of Variation of Corneal Endothelial Cells | 27.37 ± 3.76 | 29.64 ± 3.85 |
such as glaucoma, cataract, persistent uveitis, macular edema, endophthalmitis..etc.
Results for this outcome have not been posted.
Collected over within one to two years. Non-serious events are listed at a 0% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Traditional OVD Group | 0/46 (0%) | 0/46 (0%) | 1/46 (2.2%) |
| Reduced OVD Group | 0/67 (0%) | 0/67 (0%) | 0/67 (0%) |
| Event | Traditional OVD Group | Reduced OVD Group |
|---|---|---|
| GlaucomaEye disorders | 1/46 | 0/67 |
this involves all participants with complete data
| Age, Continuous(years) | Traditional OVD Group | Reduced OVD Group | Total |
|---|---|---|---|
| Mean | 32.04 ± 7.39 | 29.07 ± 8.04 | 30.23 ± 7.90 |
| Sex: Female, Male(eyes) | Traditional OVD Group | Reduced OVD Group | Total |
|---|---|---|---|
| Female | 56 | 79 | 135 |
| Male | 22 | 42 | 64 |
| Race (NIH/OMB)(Participants) | Traditional OVD Group | Reduced OVD Group | Total |
|---|---|---|---|
| American Indian or Alaska Native | 0 | 0 | 0 |
| Asian | 0 | 0 | 0 |
| Native Hawaiian or Other Pacific Islander | 0 | 0 | 0 |
| Black or African American | 0 | 0 | 0 |
| White | 46 | 67 | 113 |
| More than one race | 0 | 0 | 0 |
| Unknown or Not Reported | 0 | 0 | 0 |
| Region of Enrollment(participants) | Traditional OVD Group | Reduced OVD Group | Total |
|---|---|---|---|
| Iraq | 46 | 67 | 113 |
| Anterior Chamber Depth(Millimeter) | Traditional OVD Group | Reduced OVD Group | Total |
|---|---|---|---|
| Mean | 3.279 ± 0.299 | 3.308 ± 0.241 | 3.297 ± 0.265 |
| Endothelial Cell Density(cells per square millimeter) | Traditional OVD Group | Reduced OVD Group | Total |
|---|---|---|---|
| Mean | 2793.75 ± 310.6 | 2904.56 ± 307.4 | 2861.47 ± 312.6 |
| Corneal endothelial coefficient of variation(unitless) | Traditional OVD Group | Reduced OVD Group | Total |
|---|---|---|---|
| Mean | 29.6 ± 4.4 | 29.6 ± 3.9 | 29.6 ± 4.1 |
| Corneal endothelial cells hexagonality(percentage) | Traditional OVD Group | Reduced OVD Group | Total |
|---|---|---|---|
| Mean | 58.22 ± 10.55 | 58.30 ± 9.77 | 58.27 ± 10.07 |
4 further baseline measures are reported on the registry.
PDFs hosted by the registry, ClinicalTrials.gov.
This study is completed, as verified in Nov 2024. You cannot join it, but the record below documents what was studied.
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