WJORV
10.5005/jp-journals-10020-1010
REVIEW ARTICLE
20 Gauge Sutureless Vitrectomy
20 Gauge Sutureless Vitrectomy
1
Pukhraj Rishi, 2Sabyasachi Sengupta
1
Consultant, Shri Bhagwan Mahavir Vitreoretinal Services, Sankara Nethralaya, Chennai, Tamil Nadu, India
2
Fellow, Shri Bhagwan Mahavir Vitreoretinal Services, Sankara Nethralaya, Chennai, Tamil Nadu, India
Correspondence: Pukhraj Rishi, Consultant, Shri Bhagwan Mahavir Vitreoretinal Services, Sankara Nethralaya, 18 College
Road, Chennai-600006, Tamil Nadu, India, Phone: 91-4428271616, Fax: 91-4428254180, e-mail: [email protected]
ABSTRACT
Objective: To review available peer-reviewed publications to evaluate the efficacy of 20 gauge sutureless pars plana vitrectomy.
Methods: Literature searches of the PubMed and the Cochrane Library databases were conducted with no date restrictions; the searches
were limited to articles published in English only. All publications with level II and III evidence were studied extensively. A comparison of this
technique was also performed with available results from other small gauge sutureless vitrectomy techniques.
Results: The overall safety profile of 20 gauge sutureless pars plana vitrectomy is similar to that established for conventional 20 gauge pars
plana vitrectomy and provides comparable visual acuity results. Compared with conventional vitrectomy, this technique is associated with
significantly lower levels of patient discomfort and ocular inflammation, and the time required for improvement in visual acuity is shorter.
Recent modifications in techniques of making biplanar sclerotomies along with application of fibrin tissue adhesives to the sclerotomy and
conjunctival openings make this procedure comparable to smaller guage transconjunctival sutureless vitrectomies, but with the advantage
of retaining advanced fluidics.
Conclusions: In this review, the authors enlist various surgical techniques and their modifications in 20 gauge sutureless pars plana
vitrectomy and summarize the emerging results from early studies conducted in this novel approach. Current evidence warrants conducting
prospective, randomized and controlled clinical trials to compare this technique with conventional 20G vitrectomy as well as the newer
smaller gauge vitrectomy techniques. As surgical techniques evolve and clinical experience grows, continued close surveillance is necessary
for an accurate assessment of complications.
Keywords: Vitrectomy, Trans-scleral sutureless vitrectomy (TSV), 20 gauge, Tissue adhesive, Surgery.
INTRODUCTION
Pars plana vitrectomy has brought about a paradigm shift and
revolutionized retinal surgery since its introduction by
Machemer et al in 1971.1 With the established safety and
efficacy of this technique, the indications have expanded with
gratifying results. Conventional 20 gauge vitrectomy involves
making three sclerotomy ports after a limited conjunctival
dissection followed by suturing these sclerotomies and
conjunctiva at the end of the procedure. The quest to find ways
to shorten surgical time and to minimize trauma to the eye led
to the development of the first 20G transconjunctival sutureless
approach in 1996 by Chen et al.2 The introduction of 23, 25
and the recently introduced 27G vitrectomy systems have
reduced surgical time and improved patient comfort enabling
early rehabilitation.3, 4
The basis of a sutureless pars plana sclerotomy was to
stabilize the intraocular pressure (IOP) during surgery with a
truly closed system as well as reduce the surgical time by
removing the need for sutured wound closure. Wound and suture
related complications, such as leakage, irritation, and scleral
pigmentary changes could also be avoided. Concerns regarding
wound competence in a sutureless procedure have seen the
modification of the conventional straight incision to techniques
such as angled, beveled, oblique and scleral tunnel incisions.
However, an incomplete armamentarium and overflexible
World Journal of Retina and Vitreous, May-August 2011;1(1):37-42
instrumentation coupled with increased risk of postoperative
hypotony, endophthalmitis and compromised fluidics have
limited the application of these new systems. Another limiting
factor was the increased cost incurred on instrumentation. In
contrast, a 20G system has sturdy instruments and excellent
fluidics albeit longer surgical times due to suturing and
additional suture related complications. Also, the retinal surgeon
desires a single vitrectomy system that could deal with varied
surgical situations, such as lensectomy for advanced nuclear
sclerosis/membranectomy of thick papillary membranes,
advanced proliferative diabetic retinopathy with extensive
fibrovascular proliferation, advanced proliferative
vitreoretinopathy, management of a dropped nucleus (grade IV)
or retained intraocular foreign body (IOFB). 20G sutureless
vitrectomy system combines the superior fluidics and stability
of 20G instruments along with the reduced surgical times and
improved patient comfort of the 23, 25G systems. The purpose
of this review is to summarize the available information on 20G
transconjunctival sutureless vitrectomy and evaluate its role in
modern-day vitreous surgery supplemented with our personal
experience.
WOUND CONSTRUCTION IN
20G SUTURELESS VITRECTOMY
Chen described a scleral tunnel technique after limited
conjunctival dissection followed by insertion of the
37
Pukhraj Rishi, Sabyasachi Sengupta
microvitreoretinal (MVR) blade into the vitreous cavity at the
base of the tunnel.2 Yeshuran described the creation of a
modified sutureless sclerotomy using a MVR blade.5 In the first
stage of sclerotomy construction, a 19G MVR blade was
advanced inside the sclera for approximately 2.5 mm at a
20º angle. It was then rotated into a vertical position, and the
vitreous cavity was penetrated.
Gotzaridis described a technique in which the MVR blade
was introduced into the conjunctiva-sclera in a beveled
direction. 6 The technique began with diathermy of the
conjunctiva with a “short neck” wide-tip diathermy probe. The
diathermy was broad and intense. The diathermy probe was
applied like “ironing clothes” (press and stretch the conjunctiva
over the sclera). The conjunctiva became thin or very thin, and
sometimes an opening was created with a gradually thinning
rim that was sealed with the underlying sclera. The visible end
point of the conjunctival burn was a white circle the size of at
least 4 to 5 mm in diameter. The adhesion between the
conjunctiva and the sclera prevented bleeding and inflation of
the subconjunctival space with infusion fluid. A 20-gauge MVR
blade was used to create a combined conjunctivoscleral incision
in the inferotemporal quadrant. A self-retaining 4 mm infusion
cannula (DORC International—Dutch Ophthalmic Research
Center, Zuidland, The Netherlands) was used in this port without
a suture. At the end of the operation, a single 8-0 vicryl
(polyglactin 910) suture was used to close the conjunctiva and
sclera together.
Patil et al described a technique in which a fornix-based
conjunctival and tenons flap was recessed by 4 mm.7 A partial
thickness (1/2-2/3 depth) scleral incision 2 to 3mm in length
was made 2.0 mm from the limbus. An angled bevel up crescent
blade was used to create a 2.0 mm scleral pocket posteriorly.
This approximated the entry into the eye to about 4mm from
the limbus. The MVR blade was passed through the scleral
pocket and rotated to 60º before entering the vitreous cavity.
The conjunctiva was approximated and diathermized at the end
of the operation.
In the technique described by Lafetá et al, incisions were
made radially at 3 mm from the limbus and tunnels were made
limbus-parallel.8 The procedure was initiated using a 20-gauge
bent stiletto (45° angle; 0.9 mm; Blumenthal; BD Visitec) that
was inserted at a 10° angle through the conjunctiva, without
displacement. The instrument set included one infusion inserter
that measured 11.5 mm, one infusion trocar measuring 8.5 mm
with a 4.0 mm intraocular extension, two blunt trocar-inserters,
measuring 10.0 mm with a 4.0 mm intraocular extension, to
place the 6.5 mm trocars. At the end, the eye was pressurized at
20 mm Hg and the infusion was closed before removing the
two trocars from the superior quadrants. Then, the infusion was
reopened, increasing the eye pressure for a few seconds with
simultaneous cotton-tip massage at the entry ports in order to
close the tunnels.
Saad et al described making a small conjunctival incision
over the site of the intended sclerotomy.9 The sclerotomies were
then constructed with a 20 gauge MVR blade introduced in the
38
sclera at a 10° angle, 1.5 mm from the limbus in aphakic or
pseudophakic eyes or 2 mm from the limbus in phakic eyes to
create a 2 mm long half-thickness scleral incision. The MVR
blade was then rotated 90° to the eye and introduced in the
mid-vitreous cavity in the normal way at the intended site of
entry (3.5 mm from the limbus in aphakic or pseudophakic eyes
or at 4 mm in phakic eyes) and withdrawn. The superior
sclerotomies were fashioned in an anteroposterior direction
perpendicular to the limbus. The infusion line sclerotomy was
fashioned in a circumferential direction parallel to the limbus,
and the infusion line was held in place with a preplaced 7.0
vicryl suture. The intraocular instruments were introduced in
the same manner as the MVR blade by passing into the scleral
incision first and then rotated to 90° before entering the vitreous
cavity. Cautery was applied to the edge of the scleral incision
to shrink the scleral fibers and help in closing the external
opening of the sclerotomy when necessary. The conjunctiva
was closed over the sclerotomy with an absorbable suture.
Of the currently available options, 20-gauge non-trocar or
trocar systems hold the possibility of providing some of the
advantages of smaller-gauge systems without the need to adopt
a lot of newer instrumentation in switching to transconjunctival
sutureless surgery.10 Sclerotomies with the Claes 20 gauge
vitrectomy system (DORC International, Zuidland, Netherlands)
are created using a two-step procedure; a regular 20-gauge
microvitreoretinal knife is inserted at an estimated angle of 10°
to 20° using the DORC fixed footplate; then the trocar is
inserted. The DORC system is equipped with a high speed
pneumatic vitrectome with closest aspiration port to the tip
enabling increased aspiration flow and instrument stiffness. The
new generation trocar design enhances smooth insertion and is
equipped with a unique closure valve that creates a closed
surgical field with constant intraocular pressure without the need
for closure plugs. For insertion of the Synergetics One-Step
Surgical System (Synergetics, O’Fallon, MO), the bladed trocar
inserter is used.11 The flexible cannula of the Synergetics system
tends to self seal during surgery.
TISSUE GLUE FOR SCLERAL AND CONJUNCTIVAL
CLOSURE AFTER 20G VITRECTOMY
Batman et al demonstrated successful closure of both, the
sclerotomy sites as well as the conjunctival peritomy, using
fibrin tissue glue (Tisseel, Baxter AG Industries, Vienna,
Austria).12After cannulae were removed, each of the entry site
was closed with one drop of fibrin glue that was immediately
applied over the edges of the sclerotomy. The edges were
opposed gently with forceps for 45 seconds for firm adhesion.
Excess sealant was excised with scissors. The wound was
checked for leakage by applying pressure to the edges of incision
with a sponge. Then, three or four drops of fibrin glue were
spread on the bare sclera near the limbus 360º and the
conjunctival was pressed into place.
Our preferred technique of 20G sutureless pars plana
vitrectomy consists of creating three biplanar sclerotomies
(Figs 1A and B), performing standard vitrectomy and at the
end of the procedure, using fibrin glue at the lips of the
JAYPEE
WJORV
20 Gauge Sutureless Vitrectomy
sclerotomy sites (Figs 2A to D) and conjunctival peritomy for
closure (Figs 3A to F). We have found this method to be very
useful for the management of a wide range of pathologies. It
also facilitates easy use of endotamponading agents whenever
necessary. Ultrasound biomicroscopy (UBM) of these slerotomy
sites at six weeks postoperative follow-up also revealed a good
healing pattern (Figs 4A and D).
A
RESULTS
Yeshurun et al5 reported that 33 out of the 35 eyes underwent
uneventful operations and only two eyes required suture
placement at the end of surgery (2.9% of sclerotomies). In
the series by Gotzaridis et al,6 only 3.5% patients suffered
from postoperative hypotony, which normalized 3 days after
operation. Lafeta et al8 reported no case of hypotony, choroidal
B
Figs 1A and B: Using a 20G MVR blade, an initial scleral dissection is done at 10o angulation to the globe to create a scleral pocket
(A) followed by entry into the vitreous cavity almost perpendicular to the scleral plane (B) to finally achieve a biplanar incision
A
B
C
D
Figs 2A to D: After application of fibrin glue to the sclerotomy site, the scleral lips are apposed for 40 to 50 seconds using toothed forceps
(A) The sclerotomy is seen to be well approximated (arrows) without leakage (B and C) which is confirmed at high magnification (D)
World Journal of Retina and Vitreous, May-August 2011;1(1):37-42
39
Pukhraj Rishi, Sabyasachi Sengupta
A
B
D
E
C
F
o
Figs 3A to F: After applying fibrin glue to the bare scleral over the temporal 180 , the edges of the conjunctival peritomy at the site of
relaxing cuts are apposed using forceps (A) followed by apposition of the superior conjunctiva at the limbus (B) till it is adhered well (C)
Fibrin glue is then applied to remaining bare sclera (D) and the cut ends of the conjunctiva on the opposite side are approximated (E)
till a good seal is attained. Excellent conjunctival closure is achieved at the end of the procedure (F) over the entire 360o
A
B
C
D
Figs 4A to D: Ultrasound biomicroscopy of sclerotomy sites reveals complete closure with no evidence of internal gaping or
vitreous incarceration in the wound
40
JAYPEE
WJORV
20 Gauge Sutureless Vitrectomy
detachment or endophthalmitis. Saad and Assi9 recently
concluded from their experience of 183 sclerotomies
performed, that 10 (6%) required suture placement. More
recently, Kim et al11 reported that, in a series of 164 20G
sutureless vitrectomies, suture placement at the end of the
procedure was required in 63 patients (38%) to close leaking
sclerotomies. In a comparative series of 21 consecutive eyes
undergoing sutureless vitrectomy using self-sealing wedgeshaped pars plana sclerotomies, Theelan et al reported no cases
of hypotony.12 Batman et al, in their study using fibrin glue to
seal sclerotomies and conjunctiva, reported complete
conjunctival reattachment and no scleral wound leakage at
the end of the surgical procedure and during the follow-up
period. No adverse effects were seen with fibrin glue
application at two months.13Abnormal fibrous ingrowth was
not detected at the sclerotomy sites by means of UBM in glue
applied eyes. Patient comfort was significantly higher in eyes
receiving glue application compared to those receiving vicryl
sutures.
Table 1 shows the results of the recently published studies
on 20G sutureless vitrectomies.
Possible complications of 20G vitrectomy include
postoperative hypotony, choroidal detachments, conjunctival
blebs, scleral flap necrosis or infection, vitreal incarceration
and endophthalmitis.14-16
CONCLUSION
In conclusion, advantages of 23G TSV system include short
procedure time, faster healing, less postoperative inflammation
and allowance of high speed cutters with superior fluidics.
Table 2 shows comparison of 20, 23 and 25G vitrectomy
systems. Despite gauge conversion, 20G parsplana vitrectomy
maintains a niche of its own. Sutureless 20G vitrectomy
techniques that have been described, can enable retinal surgeons
to graduate into this surgery without a steep learning curve.
Also, as routine instruments can be used, additional investments
are not required and this makes it economical. Advantages of
using biologic adhesives to seal sclerotomies are that it imitates
Table 2: Comaprison of 20, 23 and 25G vitrectomy systems
Parameter
20G
23G
TSV
√
√
√
Cost
Least
Higher
Highest
Full
Limited
Limited; Flimsy
Highest
Moderate
Low
Least
Moderate
Longer
Instrumentation
I/A rate
IO surgery time
25G
Hypotony
0.3%
Higher
Highest
Endophthalmitis
Least
Higher
Highest
Learning curve
Short
Moderate
Moderate
Note: TSV, Trans-scleral sutureless vitrectomy.
the final stage of the normal physiological coagulation process
and mimics physiological wound healing process. This
technique coupled with the transition back towards 20G
vitrectomy seems very promising. A randomized control trial
could bring out the comparison better and enable wider
acceptance.
REFERENCES
1. Machemer R, Buettner H, Norton EW, Parel JM. Vitrectomy:
A pars plana approach. Trans Am Acad Ophthalmol Otolaryngol
1971;75:813-20.
2. Chen JC. Sutureless pars plana vitrectomy through self-sealing
sclerotomies. Arch Ophthalmol 1996;114:1273-75.
3. Warrier SK, Jain R, Gilhotra JS, Newland HS. Sutureless
vitrectomy. Indian J Ophthalmol 2008;56:453-58.
4. Oshima Y, Wakabayashi T, Sato T, Ohji M, Tano Y. A 27 guage
instrument system for transconjuctival sutureless microincision
vitrectomy system. Ophthalmology 2010;117:93-102.
5. Yeshurun I, Rock T, Bartov E. Modified sutureless sclerotomies
for pars plana vitrectomy. Am J Ophthalmol 2004;138:866-67.
6. Gotzaridis EV. Sutureless transconjunctival 20 gauge pars plana
vitrectomy. Semin Ophthalmol 2007;22:179-83.
7. Patil BB, Mowatt L, Ho S, Scott R. Reverse self-sealing
sclerostomies. Eye 2005;19:1235-37.
8. Lafetá AP, Claes C. Twenty-gauge transconjunctival sutureless
vitrectomy trocar system. Retina 2007;27:1136-41.
9. Saad A, Assi A. Modified 20-gauge sutureless single-step
sclerotomies for pars plana vitrectomy. Retina 2009;29:
848-53.
Table 1: Comparative table of studies on 20G sutureless vitrectomy
Study
No. of eyes
Technique
Suture (%)
Comments
Milibak et al14
17
PA tunnel 20G MVR blade
58
High rate of leakage
Kwok et al15
25
Circumferential needle 20G needle
11
Suprachoroidal detachment and lens touch
Saad et al9
25
AP tunnel with crescent blade
6
Traditional incision for infusion cannula
Jackson16
30
Circumferential tunnel 20G MVR
14
High rate of leakage and other complications
Theeleen et al12
21
Wedge-shaped sclerotomy
20G MVR blade
5
Leakage, if no. of instrument exchanges are more
Yeshurun et al5
35
Circumferential oblique superior
sclerotomies with 19G MVR blade
2.9
Patil et al7
40
AP tunnel crescent blade
2.5
Lafeta et al8
50
20G trocar system
0
Need a trocar system
Blade-like trocar
38
New synergestics one step surgical system used
Kim et al11
164
Traditional incision for infusion cannula
Traditional incision for infusion cannula
Note: PA, Postero-anterior; AP, Antero-posterior.
World Journal of Retina and Vitreous, May-August 2011;1(1):37-42
41
Pukhraj Rishi, Sabyasachi Sengupta
10. Atienza NF, Say EA, Garcia CP, Tanqueco RE, Say AS.
Comparison between the DORC (Claes) and synergetics
20 gauge trocar systems for sutureless transconjunctival
vitrectomy surgery. Paper presented at: Retina Congress 2009;
Sep 30-Oct 4, 2009; New York.
11. Kim JE, Shah SN, Choi DL, et al. Transconjunctival 20-gauge
pars plana vitrectomy using a single entry cannulated sutureless
system. Retina 2009;29:1294-98.
12. Theelen T, Verbeek AM, Tilanus MA, van den Biesen PR.
A novel technique for self-sealing, wedge-shaped pars plana
sclerotomies and its features in ultrasound biomicroscopy and
clinical outcome. Am J Ophthalmol 2003;136:1085-92.
42
13. Batman C, Ozdamar Y, Mutevelli S, Sonmez K, Zilelioglu G,
Karakaya J. A comparative study of tissue glue and vicryl suture
for conjunctival and scleral closure in conventional 20-gauge
vitrectomy. Eye 2009;23:1382-87.
14. Milibák T, Süveges I. Complications of sutureless pars plana
vitrectomy through self-sealing sclerotomies. Arch Ophthalmol
1998;116:119.
15. Kwok AK, Tham CC, Lam DS, Li M, Chen JC. Modified
sutureless sclerotomies in pars plana vitrectomy. Am J
Ophthalmol 1999;127:731-33.
16. Jackson T. Modified sutureless sclerotomies in pars plana
vitrectomy. Am J Ophthalmol 2000;129:116-17.
JAYPEE