Outcomes of residentperformed phacoemulsification cataract extraction complicated by vitreous loss

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Outcomes of resident-performed phacoemulsification
cataract extraction complicated by vitreous loss

• Gowri Pachigolla, M.D., Steven Verity, M.D.,
• Preston H. Blomquist, M.D.
• April 2008

The University of Texas Southwestern Medical
Center at Dallas, TX
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Introduction

• Over 2.5 million cataract extractions are
  performed per year in the US
• 97 of cataract extraction are performed using
  phacoemulsification techniques
• Accidental vitreous loss has been associated with
  CME, glaucoma, retinal detachment,
  endophthalmitis, vitreous hemorrhage, IOL
  dislocation, corneal endothelial decompensation
  and retinal vascular occlusions
• Nevertheless most patients (67-97), even in
  training centers, achieve at least BCVA 20/40

Leaming DV. Practice styles and preferences of
ASCRS members--2003 survey. J Cataract Refract
Surg 2004 30892-900
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Introduction

• Most comparative studies in the past have found
  that outcomes after posterior capsular rupture or
  vitreous loss are significantly worse than after
  uncomplicated cases
• However, one study by Nishi demonstrated
  equivalent outcomes in several measures including
  VA, incidence of post-operative complications and
  endothelial cell loss
• More recently with phacoemulsification becoming
  the predominant technique for CE, a few studies
  have shown that in cases of vitreous loss, ECCE
  fare worse

Nishi O. Vitreous loss in posterior chamber lens
implantation. J Cataract Refract Surg 1987
13424-7. Chan FM, et al. Short-term outcomes in
eyes with posterior capsule rupture during
cataract surgery. J Cataract Refract Surg 2003
29537-41. Blomquist PH, et al. Visual outcomes
after vitreous loss during cataract surgery
performed by residents. J Cataract Refract Surg
2002 28847-52. Ah-Fat FG, et al. Vitreous loss
during conversion from conventional extracapsular
cataract extraction to phacoemulsification. J
Cataract Refract Surg 1998 24 801805.
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Purpose Methods

• To compare clinical outcomes after
  resident-performed phacoemulsification
  complicated by vitreous loss and uncomplicated
  control cases
• Retrospective comparative study of all
  consecutive patients undergoing planned
  phacoemulsification from April 2005 to March 2006
  at Parkland Memorial Hospital
• Exclusions lt4 weeks of followup, combined
  procedures, planned ECCE, h/o ruptured globe,
  dislocated native lens

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Results

• 525 consecutive patients were identified
• 127 excluded
• inadequate follow-up (67)
• combined surgical procedure (29)
• unavailable operative report (13)
• primary ECCE (5)
• cases performed by fellows (4)
• unavailable medical charts (3)
• history of ruptured globe (2)
• dislocated native lens (1)
• 4 aborted cases. 1 rescheduled within study time
  and included in the data analysis.
• A total of 398 patients were included in the study

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Results

• 3 groups
• Controls (366 eyes)
• No vitreous loss
• 2. Vitreous loss group (23 eyes)
• Completion of CE with phacoemulsification
• 3. Conversion group (9 eyes)
• Conversion to ECCE/ICCE regardless of
• vitreous loss

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Demographics
Mean follow up time was less for the Vitreous
loss group.
Unplanned operative incidents
Numbers in parenthesis are percentages
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Operative procedures and IOL Types
Most eyes in the Control group had IOLs placed
within the bag, while Sulcus and ACIOLs were more
commonly placed in the Vitreous Loss and
Conversion groups respectively.
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Preoperative lenticular characteristics
Having at lease one preoperative lenticular
pathology was more common in the Conversion group
than in the Control group. Numbers in
parenthesis are percentages P 0.006, versus
Control group (z-test)
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Late complications
Both the Vitreous Loss and Conversion groups were
more often complicated by at least one late
adverse event, while CME occurred more frequently
in the Conversion group only. Only one of the
endophthalmitis cases was culture-positive.
Numbers in parenthesis are percentages P lt
0.001, versus Control group (z-test) P 0.002
for Vitreous loss and Conversion groups versus
Controls (z-test)
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Visual outcomes
Mean logMAR BCVA (Snellen equivalent)
Postop BCVA was not significantly worse in the
Vitreous Loss group compared to Controls, with
both groups having approximately 20/30 vision.
Alternately, postop BCVA in the Conversion group
was significantly worse than in Controls with a
VA of about 20/70 in the Conversion group. P lt
0.05, versus Control group (ANOVA on ranks) P
gt 0.05, versus Control group (ANOVA on ranks)
P lt 0.05, versus Control group (ANOVA on ranks)
Percentage of eyes with postoperative BCVA 20/40
or better
P lt 0.001, versus Control group (z-test)
Postoperative BCVA excludes 57 patients in the
Control group and 2 in the Vitreous loss group
with preexisting ocular disease accounting for
BCVA lt 20/40
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Conclusion

• In the past, comparative studies evaluating
  clinical outcomes after CE complicated by
  vitreous loss have included ECCE. Given the more
  complicated postop course and variable VA
  outcomes after complicated and uncomplicated
  ECCE, the current study chose to separate these
  patients.
• The study is limited by its small sample size and
  limited follow up time however, it does conclude
  that although, vitreous loss after
  resident-performed phacoemulsification more often
  results in late complications, visual outcome is
  not significantly worse as long as complications
  do not result in conversion to EC/ICCE.
• Careful surgical planning and anticipation of
  conversion to ECCE may improve outcomes.