Glaucoma
Conditions
Keywords
Tube shunt surgery, Trabeculectomy
Brief summary
The purpose of the Primary Tube Versus Trabeculectomy (PTVT) Study is to compare the long-term safety and efficacy of nonvalved tube shunt surgery to trabeculectomy with mitomycin C in eyes that have not had previous ocular surgery.
Interventions
PROCEDURETube shunt surgery
The procedure involves implantation of a Baerveldt consisting of a tube that is connected to an end plate. The tube is inserted into the anterior chamber and shunts aqueous humor to the end plate located in the equatorial region of the eye. The aqueous humor is then absorbed by the tissues around the eye.
PROCEDURETrabeculectomy
The procedure involves removal of a small portion of trabecular meshwork and adjacent tissue under a partial thickness scleral flap. Aqueous humor drains into the subconjunctival space producing a filtering bleb. The aqueous humor then diffuse out of the bleb.
DRUGMitomycin C
A fluid retaining sponge soaked in 0.4 mg/ml Mitomycin C will be applied in the region of Trabeculectomy site for about 2 minutes
Sponsors
Abbott Medical Optics
Research to Prevent Blindness
National Eye Institute (NEI)
University of Miami
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to 85 Years
Healthy volunteers
No
Inclusion criteria
* Age 18-85 years * Glaucoma that is inadequately controlled on tolerated medical therapy with Intraocular Pressure (IOP) greater than or equal to 18 mm Hg and less than or equal to 40 mm Hg * No previous incisional ocular surgery
Exclusion criteria
* Unwilling or unable to give consent, unwilling to accept randomization, or unable to return for scheduled protocol visits * Pregnant or nursing women * No light perception vision * Active iris neovascularization or active proliferative retinopathy * Iridocorneal endothelial syndrome * Epithelial or fibrous ingrowth * Chronic or recurrent uveitis * Steroid-induced glaucoma * Severe posterior blepharitis * Unwilling to discontinue contact lens use after surgery * Previous cyclodestructive procedure * Conjunctival scarring from prior ocular trauma or cicatrizing disease precluding a superior trabeculectomy * Functionally significant cataract * Need for glaucoma surgery combined with other ocular procedures or anticipated need for additional ocular surgery
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Number of Participants With Surgical Failure | Up to 5 years | Surgical failure is defined as: 1. Inadequate Intraocular Pressure (IOP) Reduction (IOP \> 21 mmHg or reduced \< 20% below baseline on 2 consecutive follow-up visits after 3 months) 2. Reoperation for glaucoma 3. Persistent hypotony (IOP ≤ 5 mmHg on 2 consecutive visits after 3 months) 4. Loss of light perception vision |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Number of Participants With Reported Postoperative Complications | Up to 5 years | Number of participants with early and late postoperative complications will be reported as per treating physician assessment |
| Visual Acuity Using a Snellen Chart | At Baseline, At 5 years | Visual acuity will be measured using a Snellen chart on logMAR (Logarithm of Minimal Angle of Resolution) scale. Letter-by letter results calculated the visual performance score for each chart read. logMAR scores closer to zero, or below zero, indicate a better visual acuity. A logMAR visual performance score of 0.0 is equivalent to Snellen visual acuity of 20/20. |
| Visual Acuity as Measured Using EDTRS Chart | At baseline, At 5 years | Visual acuity will be reported as the number of correctly identified letters on the Early Treatment Diabetic Retinopathy Study (EDTRS) chart. Total score ranges from 0-100 with the higher score indicating better visual acuity. |
| Intraocular Pressure | At baseline, At 1 year, At 18 months, At 2 years, At 3 years, At 4 years, At 5 years | Intraocular pressure will be reported in mmHg and measured using Goldmann applanation tonometry or a Tono-Pen. |
| Reoperation for Glaucoma | Up to 5 years | The number of participants requiring reoperation for glaucoma will be reported |
| Number of Glaucoma Medications | At Baseline, At 1 year, At 18 months, At 2 years, At 3 years, At 4 years, At 5 years | The need for supplemental glaucoma medications will be reported as the number of glaucoma medications used |
| Visual Field | Up to 5 years | Visual fields will be measured using standard automated perimetry. |
Countries
Canada, United Kingdom, United States
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Tube Shunt Surgery Group Participants in this group will receive a tube shunt surgery (Baerveldt Glaucoma implant).
Tube shunt surgery: The procedure involves implantation of a Baerveldt consisting of a tube that is connected to an end plate. The tube is inserted into the anterior chamber and shunts aqueous humor to the end plate located in the equatorial region of the eye. The aqueous humor is then absorbed by the tissues around the eye. | 125 |
| Trabeculectomy With Mitomycin C Participants in this group will receive a Trabeculectomy surgery with Mitomycin C
Trabeculectomy: The procedure involves removal of a small portion of trabecular meshwork and adjacent tissue under a partial thickness scleral flap. Aqueous humor drains into the subconjunctival space producing a filtering bleb. The aqueous humor then diffuse out of the bleb.
Mitomycin C: A fluid retaining sponge soaked in 0.4 mg/ml Mitomycin C will be applied in the region of Trabeculectomy site for about 2 minutes | 117 |
| Total | 242 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 |
|---|---|---|---|
| Overall Study | Death | 5 | 5 |
| Overall Study | Lost to Follow-up | 29 | 25 |
Baseline characteristics
| Characteristic | Trabeculectomy With Mitomycin C | Total | Tube Shunt Surgery Group |
|---|---|---|---|
| Age, Continuous | 60.8 years STANDARD_DEVIATION 12.3 | 61.4 years STANDARD_DEVIATION 11.8 | 62.0 years STANDARD_DEVIATION 11.4 |
| Race/Ethnicity, Customized Asian | 7 Participants | 13 Participants | 6 Participants |
| Race/Ethnicity, Customized Black | 57 Participants | 116 Participants | 59 Participants |
| Race/Ethnicity, Customized Hispanic | 6 Participants | 15 Participants | 9 Participants |
| Race/Ethnicity, Customized Other | 2 Participants | 3 Participants | 1 Participants |
| Race/Ethnicity, Customized White | 45 Participants | 95 Participants | 50 Participants |
| Sex: Female, Male Female | 41 Participants | 82 Participants | 41 Participants |
| Sex: Female, Male Male | 76 Participants | 160 Participants | 84 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | 5 / 125 | 5 / 117 |
| other Total, other adverse events | 51 / 125 | 72 / 117 |
| serious Total, serious adverse events | 0 / 125 | 0 / 117 |
Outcome results
Primary
Number of Participants With Surgical Failure
Surgical failure is defined as: 1. Inadequate Intraocular Pressure (IOP) Reduction (IOP \> 21 mmHg or reduced \< 20% below baseline on 2 consecutive follow-up visits after 3 months) 2. Reoperation for glaucoma 3. Persistent hypotony (IOP ≤ 5 mmHg on 2 consecutive visits after 3 months) 4. Loss of light perception vision
Time frame: Up to 5 years
Population: The number of participants requiring glaucoma operations includes only those that had a failed surgery due to glaucoma reoperation.
| Arm | Measure | Group | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|---|
| Tube Shunt Surgery Group | Number of Participants With Surgical Failure | Inadequate IOP reduction | 31 Participants |
| Tube Shunt Surgery Group | Number of Participants With Surgical Failure | Reoperation for Glaucoma | 18 Participants |
| Tube Shunt Surgery Group | Number of Participants With Surgical Failure | Loss of light perception vision | 0 Participants |
| Tube Shunt Surgery Group | Number of Participants With Surgical Failure | Persistent Hypotony | 0 Participants |
| Trabeculectomy With Mitomycin C | Number of Participants With Surgical Failure | Persistent Hypotony | 5 Participants |
| Trabeculectomy With Mitomycin C | Number of Participants With Surgical Failure | Inadequate IOP reduction | 23 Participants |
| Trabeculectomy With Mitomycin C | Number of Participants With Surgical Failure | Loss of light perception vision | 1 Participants |
| Trabeculectomy With Mitomycin C | Number of Participants With Surgical Failure | Reoperation for Glaucoma | 9 Participants |
Secondary
Intraocular Pressure
Intraocular pressure will be reported in mmHg and measured using Goldmann applanation tonometry or a Tono-Pen.
Time frame: At baseline, At 1 year, At 18 months, At 2 years, At 3 years, At 4 years, At 5 years
Population: Participants who underwent additional glaucoma surgery were censored from analysis after reoperation. Not all participants completed all visits to complete the IOP assessment.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Tube Shunt Surgery Group | Intraocular Pressure | Intraocular Pressure: 18 months | 13.5 mmHg | Standard Deviation 4.1 |
| Tube Shunt Surgery Group | Intraocular Pressure | Intraocular Pressure: 3 years | 13.9 mmHg | Standard Deviation 4.2 |
| Tube Shunt Surgery Group | Intraocular Pressure | Intraocular Pressure: 1 year | 13.8 mmHg | Standard Deviation 4.1 |
| Tube Shunt Surgery Group | Intraocular Pressure | Intraocular Pressure: 4 years | 13.5 mmHg | Standard Deviation 3.5 |
| Tube Shunt Surgery Group | Intraocular Pressure | Intraocular Pressure: 2 years | 13.6 mmHg | Standard Deviation 3.9 |
| Tube Shunt Surgery Group | Intraocular Pressure | Intraocular Pressure: 5 years | 13.4 mmHg | Standard Deviation 3.5 |
| Tube Shunt Surgery Group | Intraocular Pressure | Intraocular Pressure: Baseline | 23.3 mmHg | Standard Deviation 4.9 |
| Trabeculectomy With Mitomycin C | Intraocular Pressure | Intraocular Pressure: 5 years | 13.0 mmHg | Standard Deviation 5.2 |
| Trabeculectomy With Mitomycin C | Intraocular Pressure | Intraocular Pressure: Baseline | 23.9 mmHg | Standard Deviation 5.7 |
| Trabeculectomy With Mitomycin C | Intraocular Pressure | Intraocular Pressure: 1 year | 12.4 mmHg | Standard Deviation 4.4 |
| Trabeculectomy With Mitomycin C | Intraocular Pressure | Intraocular Pressure: 18 months | 12.8 mmHg | Standard Deviation 4.7 |
| Trabeculectomy With Mitomycin C | Intraocular Pressure | Intraocular Pressure: 2 years | 12.9 mmHg | Standard Deviation 5.2 |
| Trabeculectomy With Mitomycin C | Intraocular Pressure | Intraocular Pressure: 3 years | 12.1 mmHg | Standard Deviation 4.8 |
| Trabeculectomy With Mitomycin C | Intraocular Pressure | Intraocular Pressure: 4 years | 13.5 mmHg | Standard Deviation 5.4 |
Secondary
Number of Glaucoma Medications
The need for supplemental glaucoma medications will be reported as the number of glaucoma medications used
Time frame: At Baseline, At 1 year, At 18 months, At 2 years, At 3 years, At 4 years, At 5 years
Population: Participants who underwent additional glaucoma surgery were censored from analysis after reoperation. Not all participants completed all visits to complete assessment.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Tube Shunt Surgery Group | Number of Glaucoma Medications | 2 years | 2.2 glaucoma medications used | Standard Deviation 1 |
| Tube Shunt Surgery Group | Number of Glaucoma Medications | Baseline | 3.1 glaucoma medications used | Standard Deviation 1.1 |
| Tube Shunt Surgery Group | Number of Glaucoma Medications | 3 years | 2.1 glaucoma medications used | Standard Deviation 1.4 |
| Tube Shunt Surgery Group | Number of Glaucoma Medications | 4 years | 2.3 glaucoma medications used | Standard Deviation 1.4 |
| Tube Shunt Surgery Group | Number of Glaucoma Medications | 18 months | 2.1 glaucoma medications used | Standard Deviation 1.3 |
| Tube Shunt Surgery Group | Number of Glaucoma Medications | 5 years | 2.2 glaucoma medications used | Standard Deviation 1.3 |
| Tube Shunt Surgery Group | Number of Glaucoma Medications | 1 year | 2.1 glaucoma medications used | Standard Deviation 1.4 |
| Trabeculectomy With Mitomycin C | Number of Glaucoma Medications | 5 years | 1.3 glaucoma medications used | Standard Deviation 1.4 |
| Trabeculectomy With Mitomycin C | Number of Glaucoma Medications | Baseline | 3.2 glaucoma medications used | Standard Deviation 1.1 |
| Trabeculectomy With Mitomycin C | Number of Glaucoma Medications | 1 year | 0.9 glaucoma medications used | Standard Deviation 1.4 |
| Trabeculectomy With Mitomycin C | Number of Glaucoma Medications | 18 months | 0.8 glaucoma medications used | Standard Deviation 1.3 |
| Trabeculectomy With Mitomycin C | Number of Glaucoma Medications | 2 years | 1.0 glaucoma medications used | Standard Deviation 1.5 |
| Trabeculectomy With Mitomycin C | Number of Glaucoma Medications | 4 years | 1.3 glaucoma medications used | Standard Deviation 1.4 |
| Trabeculectomy With Mitomycin C | Number of Glaucoma Medications | 3 years | 1.2 glaucoma medications used | Standard Deviation 1.5 |
Secondary
Number of Participants With Reported Postoperative Complications
Number of participants with early and late postoperative complications will be reported as per treating physician assessment
Time frame: Up to 5 years
| Arm | Measure | Group | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|---|
| Tube Shunt Surgery Group | Number of Participants With Reported Postoperative Complications | Early Postoperative Complications | 24 Participants |
| Tube Shunt Surgery Group | Number of Participants With Reported Postoperative Complications | Late Postoperative Complications | 27 Participants |
| Trabeculectomy With Mitomycin C | Number of Participants With Reported Postoperative Complications | Early Postoperative Complications | 40 Participants |
| Trabeculectomy With Mitomycin C | Number of Participants With Reported Postoperative Complications | Late Postoperative Complications | 32 Participants |
Secondary
Reoperation for Glaucoma
The number of participants requiring reoperation for glaucoma will be reported
Time frame: Up to 5 years
Population: The number of participants requiring glaucoma operations includes those that had a failed surgery due to glaucoma reoperation, as well as, other patients who failed because of inadequate intraocular pressure reduction and subsequently underwent glaucoma surgery.
| Arm | Measure | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|
| Tube Shunt Surgery Group | Reoperation for Glaucoma | 21 Participants |
| Trabeculectomy With Mitomycin C | Reoperation for Glaucoma | 12 Participants |
Secondary
Visual Acuity as Measured Using EDTRS Chart
Visual acuity will be reported as the number of correctly identified letters on the Early Treatment Diabetic Retinopathy Study (EDTRS) chart. Total score ranges from 0-100 with the higher score indicating better visual acuity.
Time frame: At baseline, At 5 years
Population: Not all participants were able to complete the 5 year follow up visit and assessments.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Tube Shunt Surgery Group | Visual Acuity as Measured Using EDTRS Chart | Baseline | 73 letters | Standard Deviation 20 |
| Tube Shunt Surgery Group | Visual Acuity as Measured Using EDTRS Chart | 5 years | 69 letters | Standard Deviation 23 |
| Trabeculectomy With Mitomycin C | Visual Acuity as Measured Using EDTRS Chart | Baseline | 73 letters | Standard Deviation 20 |
| Trabeculectomy With Mitomycin C | Visual Acuity as Measured Using EDTRS Chart | 5 years | 66 letters | Standard Deviation 27 |
Secondary
Visual Acuity Using a Snellen Chart
Visual acuity will be measured using a Snellen chart on logMAR (Logarithm of Minimal Angle of Resolution) scale. Letter-by letter results calculated the visual performance score for each chart read. logMAR scores closer to zero, or below zero, indicate a better visual acuity. A logMAR visual performance score of 0.0 is equivalent to Snellen visual acuity of 20/20.
Time frame: At Baseline, At 5 years
Population: Not all participants were able to complete the 5 year follow up visit and assessments.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Tube Shunt Surgery Group | Visual Acuity Using a Snellen Chart | Baseline | 0.20 logMAR | Standard Deviation 0.42 |
| Tube Shunt Surgery Group | Visual Acuity Using a Snellen Chart | 5 years | 0.30 logMAR | Standard Deviation 0.54 |
| Trabeculectomy With Mitomycin C | Visual Acuity Using a Snellen Chart | Baseline | 0.25 logMAR | Standard Deviation 0.51 |
| Trabeculectomy With Mitomycin C | Visual Acuity Using a Snellen Chart | 5 years | 0.42 logMAR | Standard Deviation 0.21 |
Secondary
Visual Field
Visual fields will be measured using standard automated perimetry.
Time frame: Up to 5 years
Population: No data is reported for this outcome as data can not be extracted from system despite exhausting all efforts to do so.