This document provides an overview of vitrectomy principles and techniques. It discusses the history and evolution of vitrectomy surgery. It covers surgical anatomy, the main aims of vitrectomy, components of vitrectomy machines and their functions. It describes techniques for sclerotomies, vitreous cutters, infusion cannulas and viewing systems. It outlines the basic steps of a closed vitrectomy procedure and discusses adjunctive procedures like air-fluid exchange and use of perfluorocarbon liquids, silicone oil and gases. Recent advances discussed include 25-gauge vitrectomy and endoscope-assisted surgery.
2. Introduction
1968-open sky vitrectomy-KASNER
1971-closed system vitrectomy-modern
pars plana surgery -MACHEMER
Bimanual vitrectomy-O’MALLEY
CHARLES ,SCHEPENS,PEYMAN-
instrumentation&surgical techniques.
5. Pars Plicata-2.5 MM
Pars Plana –3-5MM
Ora –5-7MM From Limbus
Vitreous Base-2-6mm wide zone
straddling the ora, extending 2-3mm
posterior to it .
6.
7. Main Aims
Clearing the media & access to
diseased retina,space for
int.tamponade
Retinal manipulation & reattachment
Release of v-r traction
Removal of tissue or foreign material &
to obtain vit. biopsy.
11. Conventional
Plano concave lenses
Hand held contact
lenses,placed on a
ring,self stabilizing
Small
field,nonmagnified
Additional lenses reqd
High
resolution,excellent
stereopsis
12. Wide Angle System
Contact
Non Contact
Stereroscopic Diagonal Invertor reqd
14. LENS MAG FIELD USE
PLANO
CONCAVE FLAT
1.0 20* POSTERIOR
POLE
,CENTRAL
VITREOUS
PRISM LENS 1.0 20* MIDPERIPHERA
L FUNDUS AND
VITREOUS
SUPER
MACULA (V)
1.03 64*-77* POSTERIOR
POLE
,CENTRAL
VITREOUS
MINI QUAD 0.71 106*-127* UPTO ORA
LANDERS
WIDEFIELD
0.38 130*-146* UPTO ORA
LANDERS
EQUATORIAL
0.65 101*-131* GOOD UPTO
EQUATOR
15. Vitreous Cutter
Presence of outer
fixed tube and an
opening thru’ which
vit. is aspirated.
Inner tip slides
across inner Port. of
opening thus cutting
the vitreous
Eg.Guillotine,Rotatio
n,Oscillation.
Safe to use low
suction,high cut rate
17. Aspiration
Device based on venturi principle creates
vacuum used to provide aspiration
The venturi has inlet for compressed air
& uses the energy from air to produce a
vacuum.
21. Intraocular Irrigating Solution
CRITERIA–should be sterile,isotonic and
which constitute near those of normal
ocular fluid and with a balanced pH.
Mixture of GBR(glutathione, bicarbonate
and ringer lactate).
BSSPlus with similar comb.
Lens opacification in diabetic pt.
Advocated- Glucose fortified BSS Plus
Regular BSS Plus for non diabetic pt.
22. Before You Begin
Inspection and testing of cutter for
cutting and aspiration
Flushing of air bubble from system &
infusion canula.
Testing of fiberoptic probe/light pipe.
Adjustment of infusion bottle height.
28. Basic closed Vitrectomy
Confirm infusion canula in and start fluid
Insert light pipe and cutter
Cutting and suction activated by cutter
Viewing system and parameters of suction
and cutting vary depending on a given
condition and plane of working
Basic eye movements are made by
exerting equal forces with 2 instr. in same
direction.
In Phakics imp. to avoid possible damage
to the lens.
36. Air fluid exchange
Air via infusion canula
(pump)
Active aspiration
Passive aspiration
Removal of SRF
37. Use of PFCL
Giant retinal tear
PVR
Dislocated nucleus / dropped nucleus
38. Use of silicone oil
PVR
Diabetic vitrectomies
For prolonged tamponade
39. Use of gases C3f8 Sf6
Pneumoretinopexy
Tamponade
40. Recent advances
25 G vitrectomy –transconjunctival,sutureless
Tried in less complicated cases like
ERM /Diabetic macular edema/ macular hole
/persistent vitreous haem
4-port vitrectomy(both hands actively
functioning with help of chandelier system)
23 G
Endoscope assisted
OFFICE system
41. Write the OT notes of the following situations
Recent Total RRD in a 60 year old
patient
Recent TRD in a diabetic patient
Fresh Vit. Hg in a 35 yr old male patient
Fresh Rd from 2 to 4 o clock in a young
patient