740
document
Microbiologic yields and complication rates of vitreous needle aspiration versus mechanized vitreous biopsy in the Endophthalmitis Vitrectomy Study . PURPOSE To compare the microbiologic yields and complication rates associated with vitreous needle tap and vitreous biopsy in the Endophthalmitis Vitrectomy Study ( EVS ) . METHODS Of 420 EVS patients with postoperative endophthalmitis , 201 received immediate vitreous tap or biopsy ( without pars plana vitrectomy ) by random assignment and 193 completed 9-12 months of follow-up . Vitreous specimens were obtained by biopsy with a 20-gauge vitrectomy cutting instrument or by needle tap with a 22-27-gauge needle . If resistance to aspiration by needle tap was noted , a vitreous biopsy was performed . RESULTS Of 201 patients undergoing tap or biopsy , 70 ( 35 % ) had needle tap , 127 ( 63 % ) had mechanized biopsy , and 4 ( 2 % ) had initial needle tap that was aborted to mechanized biopsy ( " abort " eyes ) . Intraoperative hyphema occurred in 2 tap eyes ( 3 % ) , 3 biopsy eyes ( 2 % ) , and 0 ( 0 % ) abort eyes . Postoperative retinal detachment developed in 8 ( 11 % ) tap eyes , 10 ( 8 % ) biopsy eyes , and 0 ( 0 % ) abort eyes ( not significant ) . Respective rates of culture and gram stain positivity were 69 % and 42 % in tap eyes and 66 % and 41 % in biopsy eyes ( not significant ) . The rate of severe visual loss ( final acuity < 5/200 ) was significantly higher in tap eyes ( 16 eyes , 24 % ) compared with biopsy eyes ( 13 eyes , 11 % ) and abort eyes ( 0 eyes , 0 % ; P = 0.043 ) . The difference was largely explained by the greater proportion of virulent organisms in the tap eyes compared with biopsy eyes . When visual acuity outcome was defined by other thresholds ( 20/40 and 20/100 ) , the difference was not significant . CONCLUSIONS This study showed no significant differences between mechanized vitreous biopsy and needle tap with respect to microbiologic yield , operative complications , short-term ( 9-12 months ) retinal detachment risk , or visual outcome . Choice of vitreous sampling procedure must depend on the clinical judgment of the surgeon .
741
Intervention_Surgical
vitreous needle aspiration
742
Intervention_Surgical
mechanized vitreous biopsy
743
Intervention_Surgical
vitreous needle tap
744
Intervention_Physical
vitreous biopsy
745
Intervention_Surgical
vitreous tap or biopsy ( without pars plana vitrectomy )
746
Intervention_Surgical
20-gauge vitrectomy
747
Outcome_Physical
Intraoperative hyphema
748
Outcome_Physical
Postoperative retinal detachment
749
Outcome_Physical
Respective rates of culture and gram stain positivity
750
Outcome_Physical
rate of severe visual loss
751
Outcome_Physical
proportion of virulent organisms in the tap eyes
752
Outcome_Physical
visual acuity outcome
753
Participant_Condition
Endophthalmitis Vitrectomy
754
Participant_Sample-size
420
755
Participant_Condition
EVS
756
Participant_Condition
postoperative endophthalmitis
757
Participant_Sample-size
201
758
Participant_Condition
immediate vitreous tap
759
Participant_Condition
biopsy
760
Participant_Sample-size
193
761
Participant_Sample-size
201
762
Participant_Condition
tap
763
Participant_Condition
biopsy
764
Participant_Sample-size
70
765
Participant_Condition
needle tap
766
Participant_Sample-size
127
767
Participant_Condition
mechanized biopsy
768
Participant_Sample-size
4
769
Participant_Condition
needle tap