Capsular Tension Rings:

1
Capsular Tension Rings

• Current Indications and Outcomes
• Maryam Mokhtarzadeh, MD
• Jayne S. Weiss, MD
• John M. Ramocki, MD
• No financial conflicts to disclose
• Kresge Eye Institute
• Detroit, Michigan

2
Background

• A CTR is a 270 degree open PMMA ring placed in
  the capsular bag during cataract surgery in cases
  with zonular instability or weakness.
• CTRs were introduced in 1991, used in Europe
  since 1993, but were only approved by the U.S.
  FDA in late 2003.
• We asked How has the introduction of CTRs
  changed the surgical experience at KEI?

3
Purpose

• To examine the history and use of capsular
  tension rings among surgeons at an academic
  center, specifically determining the indications
  and results.

4
Methods

• Retrospective chart review of all complex
  cataract surgeries from 1/2005 to 5/2007 at KEI,
  identified by billing code (66982)
• Review of operating room logs from 1/2003 to
  9/2007 to account for every CTR used at KEI and
  the local VA since FDA approval.
• Comparison of all CTR cases to a control group
  consisting of all other complex cataract
  surgeries.
• The data was analyzed for uptake, indications,
  and outcomes of CTR use.

5
Results

• Use
• The first CTR was implanted at KEI in 10/2004
• In the control group, 11 surgeons performed 254
  cases coded as complex cataract surgeries.
• In the experimental group, 8 of these surgeons
  performed 58 cataract surgeries using CTRs.
• The experimental group included every case using
  CTRs that has been performed in the history of
  the institutions studied.

6
Results

• Indications
• The most commonly listed preoperative indications
  for CTR placement were trauma (22) and
  pseudoexfoliation (17).
• Additional indications prior intraocular
  surgery, phacodonesis, subluxed lens, high
  myopia, phacomorphic glaucoma, and phacolytic
  glaucoma.
• One third of patients in the experimental group
  had no known preoperative indications for CTR
  placement.

7
Results

• Outcomes
• 85 of control cases resulted in IOL placement in
  the bag compared to 74 of CTR cases.
• 11 of control cases required anterior vitrectomy
  compared to 27 of CTR cases.
• CTRs were most frequently placed immediately
  after completion of cortical removal
• However, in cases where anterior vitrectomy was
  performed, CTRs were more frequently placed
  during phacoemulsification
• There was a single incidence of posterior CTR
  dislocation postoperatively which was
  successfully removed by pars plana vitrectomy.

8
Results
Placement of IOL
Control
CTR Used
85
74
9
Results
10
Results (cont)
Surgical Timing of CTR Use
18 16 14 12 10 8 6 4 2 0
CTRAnterior Vitrectomy
CTRNo Anterior Vitrectomy
Pre-Phaco Post-Phaco
Post-IA Unknown
Mid-Phaco
Mid-IA Post-Lens
11
Discussion

• Recently experience with CTRs has been increasing
  rapidly half of the cases in this study were
  performed between 1/2007-9/2007.
• In our patient population there are many
  preoperative indications for CTR placement, most
  common being trauma.
• CTRs are often implanted in cases with no known
  preoperative indications due to surgeon
  preference or intraoperative discovery of zonular
  instability.
• Review of surgical boarding forms and consents
  revealed that the decision to place CTRs is most
  often made intraoperatively.

12
Discussion

• Most CTRs are placed immediately after removal of
  cortex is complete.
• However, in cases requiring anterior vitrectomy,
  CTRs are more often placed during
  phacoemulsification.
• There was a higher incidence of anterior
  vitrectomy in the experimental group.
• However, there was no statistically significant
  difference between the percentages of cases where
  an IOL could be successfully placed in the
  capsular bag.
• CTRs are being used effectively in difficult
  cases.