Clinical Trial Details
— Status: Enrolling by invitation
Administrative data
| NCT number |
NCT04590651 |
| Other study ID # |
PHACOPXG |
| Secondary ID |
|
| Status |
Enrolling by invitation |
| Phase |
N/A
|
| First received |
|
| Last updated |
|
| Start date |
September 11, 2020 |
| Est. completion date |
December 11, 2023 |
Study information
| Verified date |
March 2022 |
| Source |
Helsinki University Central Hospital |
| Contact |
n/a |
| Is FDA regulated |
No |
| Health authority |
|
| Study type |
Interventional
|
Clinical Trial Summary
The study aims to document the effect cataract surgery has on the pseudoexfoliation and
pseudoexfoliation glaucoma eye. Details such has patient history, history of possible
glaucoma, intraocular pressure, status of the eye, operation parameters and postoperative
effect will be documented. The study is prospective and randomised . Patients will be divided
in to two groups: in one standard phacoemulsification cataract surgery will be preformed. In
the second group the anterior chamber angel will be aspirated an extra minute at the end of
the case with the IA probe. The aim is to determine weather this extra aspiration will have
an effect on postoperative intraocular pressure and other parameters.
Description:
This randomized clinical trial will be performed at the Helsinki University Central Hospital.
Patients that are eligible for cataract surgery will be recruited. A history of
pseudoexfoliation or pseudoexfoliation glaucoma is required.
Preoperative data such as age, sex, ethnicity, history of diabetes and history of high blood
are recorded. If the participant has pseudoexfoliation glaucoma the following data will be
recorded: number of years elapsed since the diagnosis; number of glaucoma medications; number
of active agents; possible bilateral disease.
Visual acuity is attained during every visit (preoperatively and 1 day, 1 week, 1 month, 6
months, 1 year, 2 years and 3 years postoperatively) using the Snellen chart. Both
uncorrected and best corrected visual acuity are attained.
Intraocular pressure (IOP) is also attained during every visit using the Goldmann applanation
tonometer (measured twice during each visit). The measurements will be taken between 8 a.m
and 12 p.m to minimize the effect of diurnal fluctuations.
Biomicroscopy will be done preoperatively to assess the following: conjunctival hyperemia;
possible pseudoxfoliation material on the endothelium, iris border and lens capsule; anterior
chamber angle opening (grade 0-4 using the Shaffer system); existence of the Sampaolesi line;
iris dilatation in millimeters (20 minutes after instilling 1 drop of tropicamid 5mg/ml and 1
drop of 2,5% phenylephrine; nuclear sclerosis (grades 0-4); presence of phacodonesis.
Postoperatively the anterior chamber is assessed for inflammation using the SUN nomenclature
at 1 day, 1 week, 1 months and 6 months.
Preoperatively axial length (AL), anterior chamber depth (ACD) and lens thickness (LT) are
obtained using the Haag-Streit LensStar optical biometer. Lens calculations are done using
the SRK/T, Hoffer Q, Holladay II and Barrett formulas and the best suited IOL determined.
Anterior chamber OCT (Tomey Casia 2) is attained preoperatively and at at 1 months, 6 months
and 1 year postoperatively. The following parameters are recorded: angle opening distance
(AOD) and trabecular iris surface area (TISA). Both at 500 and 750 micrometers. Nasal and
temporal (0 and 180 degrees) sites will be analyzed.
Specular microscopy will be performed preoperatively and 1 year postoperatively using the
Konan CellChek device. Cell density (cells per mm2) will be evaluated.
Macular OCT using the Heidelber Spectralis device is attained preoperatively and one month
postoperatively. The central retinal thickness (CRT) will be documented. The vitreoretinal
surface and Bruch's membrane are used as measuring points.
The ocular nerve head OCT obtained using the Heidelberg Spectralis OCT. The global nerve
fiber layer thickness is documented preoperatively, and possible progression is assessed by a
glaucoma specialist (NL) at 1 month, 1 year, 2 years and 3 years postoperatively.
The Kona FM-600 cell flare meter is also used to assess inflammation preoperatively and at 1
day, 1 week, 1 month, 6 months and 1 year postoperatively.
The visual field will be analyzed using the Haag-Streit Octopus static perimeter with the G
program. Perimetry is performed at 1 month ,1 year, 2 years and 3 years postoperatively. Mean
defect (MD), square root of loss variance (sLV) and reliability factor will be documented.
Randomisation is done before the cataract surgery after the preoperative evaluation.
Stratified block randomization is used to ensure that intraocular pressure and participant
age do not vary too much between the groups. The participants are randomized into two groups:
in the first group standard phacoemulsification is performed and an intraocular lens (IOL) is
implanted. In the second group an extra one-minute anterior chamber angle aspiration is
preformed using the IA tip after all the viscoelastic is aspirated from the anterior chamber.
The aim is not to touch the chamber angle with the IA tip but rather make continuous sweeping
motions under visual control during that minute.
Three surgeons (KK; ML; PK) from the Department of Corneal and Anterior Segment Surgery are
designated to perform the surgeries. Preoperative drops include one drop of tropicamide 5
mg/ml, 2,5% phenylephrine and apraclonidine 10 gm/ml. The eye is disinfected with either
iodine or chlorhexidine drops, and the lids swiped with alcohol swabs. XylocainⓇ 2% gel is
used for anesthetic after rinsing the surface of the globe. The main incision is 2,4 mm and
the side port 1 mm wide. Intracameral lidocaine and phenylephrine are used after making the
side port incision. DiscoViscⓇ and ViscoatⓇ can be used as viscoelastic agents during
surgery. The use of a Malyugin ring Ⓡ , iris hooks, capsular support hooks and a capsular
tension ring is permitted. The need for these instruments will be determined by the surgeon
during the procedure. Phacoemulsification is performed using the stop & chop or direct chop
technique. The Alcon CenturionⓇ device is used in all surgeries with the same predetermined
settings. Johnson & Johnson TecnisⓇ monofocal 1-piece IOL (ZCB00) is used in all cases. The
following data is recorded during surgery: surgeons initials; surgery time in minutes (form
the time the first incision is made to the time the wounds are sealed); surgery technique;
the use of a Malyugin Ⓡ ring or capsular tension ring; the use of iris hooks or capsular
support hooks; cumulative dissipated energy (CDE); ultrasound total time; total aspiration
time; estimated fluid aspirated; fluid used ( calculated by subtracting the amount of fluid
left at the end of the case form the amount left after priming the phaco device); possible
extra anterior chamber angle aspiration.
Postoperatively a drop of apraclonidine 10 mg/ml is instilled after a 30 to 60-minute period
of monitoring the patient in the recovery room. If the intraocular pressure pressure is under
5 or over 25 (measured with the iCareⓇ rebound tonometer by a nurse) the surgeon is asked to
assess the situation.
Complications such as posterior capsule rupture and suprachoroidal hemorrhage are grounds for
discontinuation of participation in the study.
The postoperative visits take place at 1 day, 1 week, 1 month, 6 months, 1 year, 2 years and
3 years. The types of examinations preformed are described in detail above.
The primary aim of this study is to determine the change in intraocular pressure
postoperatively. The study also aims to determine the factors effecting the change in IOP.
For this reason, patient history, glaucoma history, the status of the eye and data form the
surgery are recorded and numerous tests will be performed. These are described in detail
above. This study is aimed to aid clinicians in everyday work, for that and safety reasons a
wash-out period will not be included. Adding additional glaucoma medication is permitted
during the course of the study and the number of medications and active agents is documented
during the postoperative exams. The need for additional glaucoma medication will be assessed
during follow-up examinations with the aid of IOP measurement, ONH-OCT and perimetry.
The study also aims to determine the rate of macular edema at 1 month postoperatively, for
that reason the central retinal thickness is recorded preoperatively and at 1 month
postoperatively using the Heidelberg Spectralis OCT device.
The study will also determine the rate of endothelial cell loss at 1 year postoperatively.
