GRS Sessions at the Meeting in Queenstown, February 2008

Screening for glaucoma – what do we know and what studies do we need?
Chairpersons: Makoto Araie and Paul Foster

  • The case for population screening for glaucoma alone is controversial. A stronger case can be made for screening for visual dysfunction from all causes.
  • Opportunistic glaucoma case-finding in ophthalmic and optometric practice should be actively promoted.
  • No single test offers sufficiently high discriminative performance in the community setting where early coexistent ophthalmic and neurological pathology is relatively widespread.
  • Combined psychophysical and imaging tests do offer good sensitivity and specificity for detection of glaucoma.

Diagnosis of glaucoma - when is early diagnosis important? What is the standard in the developed world?"
Chairpersons Linda Zangwill and David Garway-Heath:

  • Is a glaucoma-damaged nerve more susceptible to further damage?
  • a. Thierry Zeyen summarized the epidemiological evidence supporting and disputing the idea that a glaucoma damaged nerve is more like to progress.

    b. Claude Burgoyne highlighted the importance of controlling for IOP and blood flow in experimental studies of glaucomatous progression.

  • We should aim to identify the earliest signs of structural damage (point – counterpoint)
  • a. Donald Budenz outlined the importance of detecting structural damage to diagnose glaucoma

    b. Stefano Gandolfi countered with evidence that it is not necessary to detect the earliest sign of glaucomatous structural damage.

  • We should be using tests of selective visual function to identify the earliest signs of functional damage (point – counterpoint)
  • a. Richard Mills argued that selective visual function tests can be helpful for detecting glaucoma

    b. Anders Heijl stated that using accepted methods for systematic literature reviews there is no evidence that SWAP or FDT detecs glaucomatous field loss earlier than SAP, but of course that more pahtological findings are detected if more tests are used. SAP offer advantages: long experience, good methods for computer-assisted analysis, mature technology,large dynamic range.

Judging progression of glaucoma – Is it necessary to follow both structure and function or is one enough?
Chairpersons: Balwantray Chauhan and Anders Heijl

  • Anders Heijl and Bal Chauhan presented contrasting viewpoints on the tools that should be used to monitor glaucoma patients once glaucoma damage was confirmed. Anders. Heijl argued that perimetry alone was sufficient while Bal Chauhan felt that monitoring the optic disc was also valuable.
  • Harry Quigley led a discussion on what tools and resources were necessary to monitor patients with glaucoma. He stressed the importance of sufficient examinations, appropriate tests and tools required to estimate progression.
  • Marcelo Nicolela discussed various thresholds of visual field and optic disc changes required to trigger changes in clinical management. He broached issues of different clinical settings and both patient and physician objectives.
  • Finally, Mark Sherwood presented ideas on encouraging ophthalmologists that measuring visual field and optic disc progression is important. He discussed obstacles currently present, including issues of training and resources.

Medical treatment of glaucoma – Resource management in the developed and underdeveloped world
Chairpersons: Anja Tuulonen and Ravi Thomas

  • To improve the cost efficiency of present health care expenditures for glaucoma, we should work to improve the worldwide performance of glaucoma care and allocation of resources. In addition to individual points of view (patients), we need to consider also societal points of view (populations).
  • We need team work to attack the problem, with other health care professionals (including optometrists) and other societies both within glaucoma and other fields in ophthalmology (e.g. AMD and diabetic retinopathy) as well as experts within related disciplines (e.g. health economics, epidemiology).
  • To start with, for proper decision making we need to produce high-quality, evidence-based data which currently is practically missing. In order to define what we want to accomplish, we need to know the future need for services. In addition, we have to gain better understanding of the magnitude of glaucoma-induced visual disability and allocation of resources. For example, there are examples in various places around the world in which there is over-testing and others where there is under-testing for glaucoma. Likewise, over- and undertreatment and over- and underspending are found within and across regions.
  • here is a strong worldwide incentive to improve the current knowledge and teaching of residents, general ophthalmologists and all health care professionals working within the field of glaucoma. We need to define levels of care (from minimum to the highest level of care) and to consider division and delegation of tasks between these levels among different professionals.
  • We need to gather data on the impact of technology on costs and outcomes, especially visual disability rates, and define its role in glaucoma care (e.g. when delegating tasks).

Basic science research in glaucoma
Chairpersons: Remo Susanna and Claude Burgoyne

Highlights of the basic science session included:

  • a summary of current knowledge on central nervous system involvement in the optic neuropathy of glaucoma by Neeru Gupta, (discussed by Harry Quigley)
  • an update on primary endothelin effects on optic nerve head astrocytes by Bal Chauhan (discussed by Marty Wax)
  • a report of Spectralis OCT detection of subsurface optic nerve head change in early experimental glaucoma by Claude Burgoyne (discussed by Jost Jonas) and
  • an explanation of the new genetic findings in pseudoexfoliation by Lee Alward (discussed by David Mackey).

Surgical treatment of glaucoma – are we doing too much or too little?
Chairpersons: Don Minckler and Franz Grehn

  • New surgical procedures are progressing toward wider application to open-angle glaucoma including canaloplasty (iScience), Trabectome (NeoMedix), and the trans-trabecuar shunt (Glaukos), all of which normalize IOP with fewer complications compared to standard filtering surgery.
  • Anti-VEGF therapy (Avastin) is widely utilized as therapy, before or in conjunction with pan-retinal photocoagulation for neovascular glaucoma associated with diabetes or other causes of retinal ischemia.
  • The ExPRESS shunt may have advantages over standard trabeculectomy in providing a consistent, relatively small fistula, no need for iridectomy, and less inflammation.
  • The Tubes vs Trabeculectomy study one-year results for the first time have demonstrated equivalence in IOP control between an aqueous shunt (Baerveldt 350) and trabeculectomy with MMC.