<clinical_study>
  <!-- This xml conforms to an XML Schema at:
    https://clinicaltrials.gov/ct2/html/images/info/public.xsd -->
  <required_header>
    <download_date>ClinicalTrials.gov processed this data on September 20, 2023</download_date>
    <link_text>Link to the current ClinicalTrials.gov record.</link_text>
    <url>https://clinicaltrials.gov/ct2/show/NCT03016507</url>
  </required_header>
  <id_info>
    <org_study_id>VEREO 3</org_study_id>
    <nct_id>NCT03016507</nct_id>
  </id_info>
  <brief_title>Intraocular Pressure Variation by Pneumatic Tonometer Before and After Phacoemulsification</brief_title>
  <acronym>IPOFACO</acronym>
  <official_title>Intraocular Pressure Variation by Pneumatic Tonometer Before and After Phacoemulsification</official_title>
  <sponsors>
    <lead_sponsor>
      <agency>VER Excelência em Oftalmologia</agency>
      <agency_class>Other</agency_class>
    </lead_sponsor>
    <collaborator>
      <agency>Francisco Welington Rodrigues</agency>
      <agency_class>Other</agency_class>
    </collaborator>
  </sponsors>
  <source>VER Excelência em Oftalmologia</source>
  <oversight_info>
    <has_dmc>Yes</has_dmc>
  </oversight_info>
  <brief_summary>
    <textblock>
      The objective of this study is to evaluate the IOP variation before and 30 days after&#xD;
      performing phacoemulsification through pneumatic tonometry, in addition to evaluating the&#xD;
      factors possibly related to this variation.&#xD;
    </textblock>
  </brief_summary>
  <detailed_description>
    <textblock>
      Cataracts represent the major cause of treatable blindness in developing countries. According&#xD;
      to data , there are 45 million blind people in the world, of which 40% is due to cataract&#xD;
      etiology. In Brazil, there are about 350,000 individuals blinded by cataracts.&#xD;
&#xD;
      One of the consequences observed after the cataract surgery is the variation of intraocular&#xD;
      pressure (IOP). IOP is directly related to the volume of aqueous humor in the anterior&#xD;
      chamber. Reports of oscillations after a cataract surgery range from +1.3 to -2.5 mmHg. The&#xD;
      duration of this oscillation varies according to the literature studied. Some studies show&#xD;
      that the oscillation seen in the first postoperative year was maintained for the 10-year&#xD;
      period and was similar in patients of all ages. However, other authors have identified a&#xD;
      non-permanent oscillation, which makes this topic controversial in ophthalmology.&#xD;
&#xD;
      There are a number of factors related to the degree of IOP reduction after a cataract&#xD;
      surgery. Studies have shown that the preoperative IOP value, the depth of the anterior&#xD;
      chamber, the volume of irrigation used during surgery and the age of the patients may&#xD;
      interfere with the IOP variation in the postoperative period.&#xD;
&#xD;
      However, the gold standard tonometer for IOP measurement is Goldmann's. This measurement is&#xD;
      closely related to important characteristics of the cornea, such as its thickness and&#xD;
      curvature, and may underestimate or overestimate IOP values.&#xD;
&#xD;
      Another way to measure IOP is through a non-contact tonometer, blow or pneumatic. The blow&#xD;
      tonometer has a pneumatic system that produces a jet of air, which leads to flattening of the&#xD;
      cornea and on the surface of which a beam of parallel light rays is projected, in which only&#xD;
      the reflected parallel and coaxial rays are picked up by the receiver of the device,&#xD;
      obtaining a maximum peak of light reception when the cornea is flattened. Its main advantage&#xD;
      is in its use in screening programs, the need for the use of eye drops and the lowest rates&#xD;
      of contamination. The blow tonometer, as well as the flattening tonometer, is influenced by&#xD;
      corneal factors, such as curvature and thickness, presenting the same parameters of under and&#xD;
      overestimation of IOP.&#xD;
&#xD;
      The objective of this study is to evaluate the IOP variation before and 30 days after&#xD;
      performing phacoemulsification through pneumatic tonometry, in addition to evaluating the&#xD;
      factors possibly related to this variation.&#xD;
    </textblock>
  </detailed_description>
  <overall_status>Completed</overall_status>
  <start_date>July 2015</start_date>
  <completion_date type="Actual">January 2017</completion_date>
  <primary_completion_date type="Actual">January 2017</primary_completion_date>
  <study_type>Observational</study_type>
  <has_expanded_access>No</has_expanded_access>
  <study_design_info>
    <time_perspective>Cross-Sectional</time_perspective>
  </study_design_info>
  <primary_outcome>
    <measure>Intraocular Pressure Variation by Pneumatic Tonometer Before and After Phacoemulsification</measure>
    <time_frame>Six months</time_frame>
  </primary_outcome>
  <enrollment type="Actual">100</enrollment>
  <condition>Intraocular Pressure</condition>
  <condition>Cataracts Senile</condition>
  <eligibility>
    <study_pop>
      <textblock>
        People with cataract and with good systemic health&#xD;
      </textblock>
    </study_pop>
    <sampling_method>Probability Sample</sampling_method>
    <criteria>
      <textblock>
        Inclusion Criteria:&#xD;
&#xD;
          -  older than 18 years&#xD;
&#xD;
          -  deep anterior chamber visualized by the slit lamp with open angle estimation using the&#xD;
             Van Herick technique&#xD;
&#xD;
          -  IOP lower than 21 mmHg&#xD;
&#xD;
          -  without surgical intercurrences, submitted to phacoemulsification&#xD;
&#xD;
        Exclusion Criteria:&#xD;
&#xD;
          -  younger than 18 years&#xD;
&#xD;
          -  shallow anterior chamber visualized by slit lamp with estimation of narrow angle&#xD;
&#xD;
          -  preoperative surgical complications&#xD;
&#xD;
          -  IOP greater than 21 mmHg&#xD;
&#xD;
          -  contact lens wearers&#xD;
&#xD;
          -  eye surgeries and/or ocular diseases and/or systemic disorders.&#xD;
      </textblock>
    </criteria>
    <gender>All</gender>
    <minimum_age>18 Years</minimum_age>
    <maximum_age>80 Years</maximum_age>
    <healthy_volunteers>No</healthy_volunteers>
  </eligibility>
  <location>
    <facility>
      <name>Rodrigo Egidio da Silva</name>
      <address>
        <city>Goiania</city>
        <state>GO</state>
        <zip>74180-010</zip>
        <country>Brazil</country>
      </address>
    </facility>
  </location>
  <location_countries>
    <country>Brazil</country>
  </location_countries>
  <reference>
    <citation>Poley BJ, Lindstrom RL, Samuelson TW, Schulze R Jr. Intraocular pressure reduction after phacoemulsification with intraocular lens implantation in glaucomatous and nonglaucomatous eyes: evaluation of a causal relationship between the natural lens and open-angle glaucoma. J Cataract Refract Surg. 2009 Nov;35(11):1946-55. doi: 10.1016/j.jcrs.2009.05.061.</citation>
    <PMID>19878828</PMID>
  </reference>
  <reference>
    <citation>Poley BJ, Lindstrom RL, Samuelson TW. Long-term effects of phacoemulsification with intraocular lens implantation in normotensive and ocular hypertensive eyes. J Cataract Refract Surg. 2008 May;34(5):735-42. doi: 10.1016/j.jcrs.2007.12.045.</citation>
    <PMID>18471626</PMID>
  </reference>
  <reference>
    <citation>Slabaugh MA, Bojikian KD, Moore DB, Chen PP. The effect of phacoemulsification on intraocular pressure in medically controlled open-angle glaucoma patients. Am J Ophthalmol. 2014 Jan;157(1):26-31. doi: 10.1016/j.ajo.2013.08.023. Epub 2013 Oct 30.</citation>
    <PMID>24182743</PMID>
  </reference>
  <reference>
    <citation>Damji KF, Konstas AG, Liebmann JM, Hodge WG, Ziakas NG, Giannikakis S, Mintsioulis G, Merkur A, Pan Y, Ritch R. Intraocular pressure following phacoemulsification in patients with and without exfoliation syndrome: a 2 year prospective study. Br J Ophthalmol. 2006 Aug;90(8):1014-8. doi: 10.1136/bjo.2006.091447. Epub 2006 May 3.</citation>
    <PMID>16672324</PMID>
  </reference>
  <reference>
    <citation>Bigger JF, Becker B. Cataracts and primary open-angle glaucoma: the effect of uncomplicated cataract extraction on glaucoma control. Trans Am Acad Ophthalmol Otolaryngol. 1971 Mar-Apr;75(2):260-72. No abstract available.</citation>
    <PMID>4933971</PMID>
  </reference>
  <reference>
    <citation>Yang HS, Lee J, Choi S. Ocular biometric parameters associated with intraocular pressure reduction after cataract surgery in normal eyes. Am J Ophthalmol. 2013 Jul;156(1):89-94.e1. doi: 10.1016/j.ajo.2013.02.003. Epub 2013 Apr 28.</citation>
    <PMID>23628350</PMID>
  </reference>
  <reference>
    <citation>Vincent SJ, Vincent RA, Shields D, Lee GA. Comparison of intraocular pressure measurement between rebound, non-contact and Goldmann applanation tonometry in treated glaucoma patients. Clin Exp Ophthalmol. 2012 May-Jun;40(4):e163-70. doi: 10.1111/j.1442-9071.2011.02670.x. Epub 2011 Oct 20.</citation>
    <PMID>21883774</PMID>
  </reference>
  <reference>
    <citation>Shingleton BJ, Pasternack JJ, Hung JW, O'Donoghue MW. Three and five year changes in intraocular pressures after clear corneal phacoemulsification in open angle glaucoma patients, glaucoma suspects, and normal patients. J Glaucoma. 2006 Dec;15(6):494-8. doi: 10.1097/01.ijg.0000212294.31411.92.</citation>
    <PMID>17106361</PMID>
  </reference>
  <verification_date>January 2017</verification_date>
  <study_first_submitted>January 6, 2017</study_first_submitted>
  <study_first_submitted_qc>January 6, 2017</study_first_submitted_qc>
  <study_first_posted type="Estimate">January 10, 2017</study_first_posted>
  <last_update_submitted>January 6, 2017</last_update_submitted>
  <last_update_submitted_qc>January 6, 2017</last_update_submitted_qc>
  <last_update_posted type="Estimate">January 10, 2017</last_update_posted>
  <responsible_party>
    <responsible_party_type>Principal Investigator</responsible_party_type>
    <investigator_affiliation>VER Excelência em Oftalmologia</investigator_affiliation>
    <investigator_full_name>Rodrigo Egidio da Silva</investigator_full_name>
    <investigator_title>Ophtalmologist</investigator_title>
  </responsible_party>
  <keyword>intraocular pressure</keyword>
  <keyword>phacoemulsification</keyword>
  <keyword>cataract</keyword>
  <condition_browse>
    <!-- CAUTION:  The following MeSH terms are assigned with an imperfect algorithm            -->
    <mesh_term>Cataract</mesh_term>
  </condition_browse>
  <patient_data>
    <sharing_ipd>No</sharing_ipd>
  </patient_data>
  <!-- Results have not yet been posted for this study                                          -->
</clinical_study>


download date: ClinicalTrials.gov processed this data on September 20, 2023
link text: Link to the current ClinicalTrials.gov record.
url: https://clinicaltrials.gov/ct2/show/NCT03016507
org study id: VEREO 3
nct id: NCT03016507
lead sponsor: 
collaborator: 
has dmc: Yes
The objective of this study is to evaluate the IOP variation before and 30 days after
      performing phacoemulsification through pneumatic tonometry, in addition to evaluating the
      factors possibly related to this variation.
Cataracts represent the major cause of treatable blindness in developing countries. According
      to data , there are 45 million blind people in the world, of which 40% is due to cataract
      etiology. In Brazil, there are about 350,000 individuals blinded by cataracts.

      One of the consequences observed after the cataract surgery is the variation of intraocular
      pressure (IOP). IOP is directly related to the volume of aqueous humor in the anterior
      chamber. Reports of oscillations after a cataract surgery range from +1.3 to -2.5 mmHg. The
      duration of this oscillation varies according to the literature studied. Some studies show
      that the oscillation seen in the first postoperative year was maintained for the 10-year
      period and was similar in patients of all ages. However, other authors have identified a
      non-permanent oscillation, which makes this topic controversial in ophthalmology.

      There are a number of factors related to the degree of IOP reduction after a cataract
      surgery. Studies have shown that the preoperative IOP value, the depth of the anterior
      chamber, the volume of irrigation used during surgery and the age of the patients may
      interfere with the IOP variation in the postoperative period.

      However, the gold standard tonometer for IOP measurement is Goldmann's. This measurement is
      closely related to important characteristics of the cornea, such as its thickness and
      curvature, and may underestimate or overestimate IOP values.

      Another way to measure IOP is through a non-contact tonometer, blow or pneumatic. The blow
      tonometer has a pneumatic system that produces a jet of air, which leads to flattening of the
      cornea and on the surface of which a beam of parallel light rays is projected, in which only
      the reflected parallel and coaxial rays are picked up by the receiver of the device,
      obtaining a maximum peak of light reception when the cornea is flattened. Its main advantage
      is in its use in screening programs, the need for the use of eye drops and the lowest rates
      of contamination. The blow tonometer, as well as the flattening tonometer, is influenced by
      corneal factors, such as curvature and thickness, presenting the same parameters of under and
      overestimation of IOP.

      The objective of this study is to evaluate the IOP variation before and 30 days after
      performing phacoemulsification through pneumatic tonometry, in addition to evaluating the
      factors possibly related to this variation.
time perspective: Cross-Sectional
measure: Intraocular Pressure Variation by Pneumatic Tonometer Before and After Phacoemulsification
time frame: Six months
study pop: 
sampling method: Probability Sample
criteria: 
gender: All
minimum age: 18 Years
maximum age: 80 Years
healthy volunteers: No
facility: 
country: Brazil
citation: Poley BJ, Lindstrom RL, Samuelson TW, Schulze R Jr. Intraocular pressure reduction after phacoemulsification with intraocular lens implantation in glaucomatous and nonglaucomatous eyes: evaluation of a causal relationship between the natural lens and open-angle glaucoma. J Cataract Refract Surg. 2009 Nov;35(11):1946-55. doi: 10.1016/j.jcrs.2009.05.061.
PMID: 19878828
citation: Poley BJ, Lindstrom RL, Samuelson TW. Long-term effects of phacoemulsification with intraocular lens implantation in normotensive and ocular hypertensive eyes. J Cataract Refract Surg. 2008 May;34(5):735-42. doi: 10.1016/j.jcrs.2007.12.045.
PMID: 18471626
citation: Slabaugh MA, Bojikian KD, Moore DB, Chen PP. The effect of phacoemulsification on intraocular pressure in medically controlled open-angle glaucoma patients. Am J Ophthalmol. 2014 Jan;157(1):26-31. doi: 10.1016/j.ajo.2013.08.023. Epub 2013 Oct 30.
PMID: 24182743
citation: Damji KF, Konstas AG, Liebmann JM, Hodge WG, Ziakas NG, Giannikakis S, Mintsioulis G, Merkur A, Pan Y, Ritch R. Intraocular pressure following phacoemulsification in patients with and without exfoliation syndrome: a 2 year prospective study. Br J Ophthalmol. 2006 Aug;90(8):1014-8. doi: 10.1136/bjo.2006.091447. Epub 2006 May 3.
PMID: 16672324
citation: Bigger JF, Becker B. Cataracts and primary open-angle glaucoma: the effect of uncomplicated cataract extraction on glaucoma control. Trans Am Acad Ophthalmol Otolaryngol. 1971 Mar-Apr;75(2):260-72. No abstract available.
PMID: 4933971
citation: Yang HS, Lee J, Choi S. Ocular biometric parameters associated with intraocular pressure reduction after cataract surgery in normal eyes. Am J Ophthalmol. 2013 Jul;156(1):89-94.e1. doi: 10.1016/j.ajo.2013.02.003. Epub 2013 Apr 28.
PMID: 23628350
citation: Vincent SJ, Vincent RA, Shields D, Lee GA. Comparison of intraocular pressure measurement between rebound, non-contact and Goldmann applanation tonometry in treated glaucoma patients. Clin Exp Ophthalmol. 2012 May-Jun;40(4):e163-70. doi: 10.1111/j.1442-9071.2011.02670.x. Epub 2011 Oct 20.
PMID: 21883774
citation: Shingleton BJ, Pasternack JJ, Hung JW, O'Donoghue MW. Three and five year changes in intraocular pressures after clear corneal phacoemulsification in open angle glaucoma patients, glaucoma suspects, and normal patients. J Glaucoma. 2006 Dec;15(6):494-8. doi: 10.1097/01.ijg.0000212294.31411.92.
PMID: 17106361
responsible party type: Principal Investigator
investigator affiliation: VER Excelência em Oftalmologia
investigator full name: Rodrigo Egidio da Silva
investigator title: Ophtalmologist
mesh term: Cataract
sharing ipd: No