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Biomed Pap Med Fac Univ Palacky Olomouc Czech Repub. 2018; 162:XX.
1
25-gauge vitrectomy and gas for the management of rhegmatogenous
retinal detachment
Miroslav Veitha, Zbynek Stranaka, Martin Pencaka, Jana Vranovab, Pavel Studenya
Aims. To evaluate the anatomical and functional results in patients with rhegmatogenous retinal detachment (RRD)
who underwent 25-gauge pars plana vitrectomy (PPV) with gas tamponade.
Materials and Methods. A retrospective evaluation of 126 eyes of 126 patients (79 men, 47 women) with RRD who
underwent 25-gauge PPV with gas tamponade (13% C3F8 in 87 eyes, 20% SF6 in 39 eyes). 113 patients (89.7%), were
operated on under local anaesthesia, 13 patients (10.3%) under general anaesthesia. Macula was detached in 85 eyes
(67.5%). 53 eyes had pseudophakic RRD, 73 eyes were phakic. Anatomical success of the primary intervention, change
in best corrected visual acuity (BCVA) and incidence of complications were assessed. An average follow-up period is
7.2 months (6-15).
Results. With single operation, retinal attachment was achieved in 125 eyes (99.2%); the final anatomical success
was 100%. The initial mean BCVA was 0.89 logMar (2.00 to 0.00); at the end of the follow-up period, it improved to
0.23logMAR (1.00 to -0.10), P < 0,0001. During the first post-intervention day, hypotony of the eye below 10 mmHg
was observed in 1 patient (0.8%); on the contrary, intraocular pressure was temporarily increased to 25 mmHg and
more in 36 patients (28.6%).
Conclusion. The surgical treatment of RRD using 25-gauge PPV with expansive gas tamponade renders excellent ana-
tomical results and improvement in BCVA. The incidence of complications and necessity of sclerotomy suturing are low.
Key words: 25-gauge, vitrectomy, retinal detachment, rhegmatogenous, gas, oblique, transconjunctival
Received: February 15, 2018; Accepted: June 7, 2018; Available online: June 21, 2018
https://doi.org/10.5507/bp.2018.034
aDepartment of Ophthalmology, University Hospital Kralovske Vinohrady and Third Faculty of Medicine, Charles University in Prague,
Czech Republic
bDepartment of Medical Biophysics and Medical Informatics, Third Faculty of Medicine, Charles University in Prague, Czech Republic
Corresponding author: Miroslav Veith, e-mail: mveith@email.cz
INTRODUCTION
Rhegmatogenous retinal detachment (RRD) is a
serious, vision-threatening condition which affects ap-
proximately 1 out of 10.000 people every year. The de-
velopment of RRD is caused by formation of a retinal
break followed by accumulation of intraocular fluid in
the subretinal space. Contrary to some other vitreoretinal
diseases, RRD requires a prompt surgical intervention1,2.
Current intervention methods used are scleral buckling,
pneumatic retinopexy and pars plana vitrectomy (PPV),
the latter being performed either as a sole procedure or
combined with scleral buckling3-5.
The best surgical method is still being discussed.
Treatment in often individualized based on surgeon ex-
perience and preferences, number and location of retinal
breaks, amount of subretinal fluid, state of the macula,
presence of proliferative vitreoretinopathy (PVR), condi-
tion of the lens, state of the vitreous body and overall
condition of the patient.
The development of sutureless vitrectomy methods
was a significant milestone in the vitreoretinal surgery.
Such techniques offer benefits of a mini-invasive proce-
dure with a higher post-operative comfort and faster re-
covery.
In this paper, anatomical and functional results of
25-gauge PPV for RRD are evaluated.
MATERIALS AND METHODS
We retrospectively evaluated medical records of 126
consecutive eyes of 126 patients with RRD. Patients un-
derwent primary surgery for RRD in the Department of
Ophthalmology of the Kralovske Vinohrady University
Hospital from May 2013 through June 2016. 25-gauge
PPV was performed using the Constellation vitrectomy
machine (Alcon, Forth Worth, TX, USA), with the
Ultravit vitrectomy probe with a cut rate of 5,000 cuts/
min. Resight 500 (Zeiss, Germany) was used to visual-
ise the fundus. Patient with minimum follow-up 6 month
were enrolled. None of the patients has PVR greater than
grade B.
All patients were operated by the same surgeon (MV).
113 patients (89.7%) were operated under retrobulbar an-
aesthesia (Marcain), 13 patients (10.3%) were operated
under general anaesthesia. Cannulas were placed in a
standard manner – inferotemporally for infusion cannula,
superotemporally and superonasally (in phakic eyes, 4
mm posterior to the limbus, in pseudophakic eyes, 3.5
Biomed Pap Med Fac Univ Palacky Olomouc Czech Repub. 2018; 162:XX.
2
mm posterior to the limbus). After displacing the conjunc-
tiva, the trocar/cannula system was introduced parallel to
the limbus under an angle of approximately 10°, with a
simultaneous denting of the sclera. As soon as the can-
nula top touched the sclera, the introduction angle was
changed to approximately 60°.
The procedure itself started with core vitrectomy.
Meticulous peripheral vitreous removal was performed
especially around retinal breaks in order to relieve vitreo-
retinal tractions, and also along the detached retina and
around the outlets of cannulas in order to prevent the
incarceration of the vitreous into the sclerotomies after
the extraction of cannulas at the end of the surgery. The
peripheral vitreous was removed in retroillumination us-
ing scleral indentation with light probe. In some cases,
perfluorodecalin (Arcaline, Arcadophta, France) was
applied to immobilise the detached retina and to facili-
tate the evacuation of subretinal fluid through peripheral
breaks. The decision on its application was based on the
detachment size, subretinal fluid quantity, and localisation
and size of breaks. Perfluorodecalin was also applied in
patients with detached macula when membrane peeling
was indicated. If epiretinal membrane (ERM) was appar-
ent in macula or where its presence was suspected, bril-
liant blue (Ocublue, Aurolab, India) dye was used and
ERM and internal limiting membrane (ILM) peeling was
performed. This procedure was followed by fluid-air ex-
change. Charles Flute Cannula (Alcon, Forth Worth, TX,
USA) or vitrectomy probe was used to drain fluid from
the subretinal space through the break, and subsequently,
complete fluid-air exchange was performed. Complete reti-
nal attachment was not required, where small volume of
residual subretinal fluid was present after the complete
fluid-air exchange, it was left. Retinopexy of margins of
the break and lattice degenerations was performed under
air using endolaser or cryotherapy probe. When perfluo-
rodecalin was used, retinopexy was usually performed
before the fluid-air exchange. If multiple retinal breaks
and lattice degeneration were present, 360° retinopexy
was performed. Non-expansive concentration of sulfur
hexafluoride (SF6) (Alchimia, Italy) or perfluoropropane
(C3F8) (Alchimia, Italy) was used as a tamponade in
all the patients. In patients with superior retinal breaks,
20% SF6 was usually used; in patients with inferior retinal
breaks, 13% C3F8 was usually used. The choice of gas
type also depended on its availability at the workplace.
After the extraction of the cannulas, tightness of the scle-
rotomy was checked. If leakage was present, digital mas-
sage was performed. If digital massage was not sufficient
to stop the leakage, sclerotomy was sutured using Vicryl
8-0 (Ethicon, Johnson & Johnson Int). Patients were ad-
vised on a suitable head positioning during a one-week
period depending on the location of breaks.
Patients were examined in our ophthalmology de-
partment one day after the intervention, one month, 2
months after the intervention, and then as needed. Only
patients with follow up period six month and more were
enrolled. In all the examinations, the best corrected vi-
sual acuity (BCVA) was checked using ETDRS charts
(Early Treatment Diabetic Retinopathy Study), and it
was converted to logMAR values for statistical purposes.
Intraocular pressure (IOP) was measured, and an exami-
nation was performed using a slit lamp including a biomi-
croscopy of the fundus in artificial mydriasis.
Statistical analyses were performed using statistical
software STATISTICA (version 12). For the purposes
of statistical testing, the BCVA results were converted
to logMAR equivalents. All the decisions were taken at a
significance level (alpha) of 0.05.
The anatomical success of the primary intervention
was evaluated, as well as the final anatomical success,
change in visual acuity, numbers of sutured sclerotomies
and incidence of complications. An average follow-up pe-
riod was 7.2 months (6-15).
RESULTS
126 eyes of 126 patients (79 men, 47 women) were
included in the study. Average age was 61.1 years (23-81).
Retina was detached in one quadrant in 12 eyes, in 2 to 3
quadrants in 100 eyes, and retina was completely detached
in 4 eyes. Macula was detached in 85 eyes (67.5%). One
break was detected in 53 eyes (42.1%), 3 and more in 41
eyes (32.5%). At least one break was present in inferior
retinal quadrants between numbers 4-8 in 48 eyes (38.1%).
53 eyes were pseudophakic and 73 phakic. During the
Table 1. Patient‘s demographics.
Total no. of eyes (total no. of patients) 126/126
Age, (y)
Mean ± SD 61,1 ± 10,6
Median (range) 62 (23–81)
Sex, no. (%)
Male 79
Female 47
Symptoms duration (d)
Mean ±SD 7.2 ± 5.4
Median (range) 7 (1–28)
Follow-up (mo)
Mean ± SD 7.2 ± 2.1
Median (range) 6 (6–15)
Quadrant of RD, no. of eyes
1 12
2 62
3 38
4 14
Macula detachment, no. (%) of eyes
Macula on 41 (32.5%)
Macula off 85 (67.5%)
Number of tears, no. of eyes
1 53
2
≥3
32
41
Lens status (%)
Phakic 73 (57.9%)
Pseudophakic 53 (42.1%)
RD, retinal detachment
Biomed Pap Med Fac Univ Palacky Olomouc Czech Repub. 2018; 162:XX.
3
Table 2. Visual acuity results.
Preoperative VA,
logMAR
(Snellen VA)
Postperative VA,
logMAR
(Snellen VA)
P
Macula-on RD 0.36 (0.62) 0,19 (0.81) 0.002
Macula-off RD 1.15 (0.22) 0,25 (0.66) <0.0001
All RD 0.89 (0.35) 0,23 (0.71) <0.0001
VA, Visual Acuity; RD, Retinal Detachment
follow-up period, cataract surgery was performed in 31
of 73 phakic patients (42.5%) (Table 1).
Perfluorodecalin was used in 62 eyes (49.2%), and in
19 eyes (15.1%) ERM and ILM peeling was performed.
360° retinopexy was performed in 14 patients (11.1%).
13% C3F8 was used as a tamponade in 87 eyes (69%), 20
% SF6 in 39 eyes (31%).
After the primary surgery, retinal attachment was
achieved in 125 eyes (99.2%). In one eye, another PPV
with gas tamponade was performed within one month due
to a persistent flat retinal detachment in the periphery
of the inferior temporal quadrant. The final anatomical
success rate of the whole group was 100%. Mean initial
BCVA was 0.89 logMar (2.00 to 0.00); at the end of the
follow-up period, it improved to 0.23logMAR (1.00 to
–0.10), P<0.0001 (Table 2).
In one case, at the end of the surgery, one sclerotomy
had to be sutured due to leakage; in one case, two scle-
rotomies had to be sutured, and in a case of one patient,
all three sclerotomies had to be sutured. On the first post-
operation day, a mean IOP value was 21 mmHg (9-45).
One eye was hypotonic – less than 10 mmHg (0.8%); in-
traocular pressure was 9 mmHg. In 36 patients (28.6%) in-
traocular pressure was temporarily increased to 25 mmHg
and more (25-30 mmHg in 23 eyes, 31-40 mmHg in 12
eyes, over 41 mmHg in 1 eye). The intraocular pressure
normalized with topical anti-glaucoma therapy. During
the follow-up period, one patient developed cystoid macu-
lar oedema (the eye had suffered an injury and it had been
intervened twice for strabismus), and one patient devel-
oped ERM. In one patient with high myopia and loosened
suspensory ligaments of the lens, gas penetrated into the
anterior chamber, causing a pupillary block and an eleva-
tion of the IOP. When laser iridotomy was performed,
IOP values returned to normal. No other complications
including endophthalmitis were observed.
DISCUSSION
The first generation of 25-gauge PPV was presented
by Fuji in 2002 (ref.6). Instruments used, however, were
flexible and not suitable for surgical solution of patholo-
gies which required a more complex peripheral vitrectomy
and major eye handling. It was also associated with higher
risk of peri- and postoperative complications7. In 2010,
the second generation instrumentation was introduced,
offering better fluid dynamics, improved rigidity of tools
and a wide-field illumination. It quickly became a pre-
ferred technique for surgeons who began to use it not
just for the solution of vitreous opacities and macular
diseases, but also in cases with more complex vitreoretinal
pathologies8-14.
25-gauge PPV offers many advantages, such as a
mini-invasive approach, shortened intervention time,
lower post-operative inflammatory reaction and patient’s
discomfort, minor conjunctival scarring and minor cor-
neal astigmatism9,15 . Cryosurgical approach is still use-
ful in RRD management, especially in phakic patients3,5.
However, PPV is more suitable for patients suffering from
multiple breaks in different quadrants, bullous retinal
detachment, breaks extending post-equatorially, breaks
with noticeable vitreoretinal traction, in patients with an
unclear situation as to break borders (no breaks detected
preoperatively or impossibility to identify with certainty
all the breaks during the pre-operative assessment) and
in pseudophakic patients3. With PPV, vitreoretinal trac-
tions may be relieved, and all the retinal breaks may be
precisely identified and repaired. The PPV may also help
to avoid some serious complications related to scleral
buckling3,15,16 . Cryosurgical interventions also tend to be
longer and general anaesthesia is required.
In our group, retinal attachment after primary opera-
tion was achieved in 99.2% of eyes. This result is com-
parable to those achieved by other techniques3-5. Similar
results have been published by several authors7,11,14,15,17. On
the contrary, Lai et al. achieved retinal attachment after
the primary operation only in 74% of the operated eyes12.
Operations were unsuccessful mainly in eyes with multiple
retinal breaks; the difference, however, was not statisti-
cally significant probably due to the size of the studied
group. Our group included 41 eyes (32.5%) with three
and more breaks, and in all the cases, retinal attachment
was achieved after the primary surgery. In a case of one
eye which required another intervention, there were two
breaks in superior quadrants. As a standard, the above-
mentioned authors performed a 360° thorough removal of
the vitreous base. However, we perform just an extended
core vitrectomy, and peripheral vitreous is meticulously
removed only at the borders of retinal breaks and along
the detached retina. We do not perform extensive pe-
ripheral vitrectomy at sites without obvious vitreoretinal
tractions. This approach may reduce the risk of minor
iatrogenic retinal breaks development which may easily
remain undetected and become the reason for operation
failure. In case of multiple retinal breaks and peripheral
retinal degenerations, 360° retinopexy was performed (in
a total of 14 eyes), which could also contribute to a better
anatomical success in our group. Other authors confirm
this assumption. Acar et al. presented a group of 22 oper-
ated eyes, in which a meticulous 360° removal of vitreous
base was performed, and 360° laser peripheral retinopexy
was performed in all the eyes. In 21 eyes, primary retinal
attachment was achieved (95.5%) (ref.15). In the group
of Miller et al. retinal attachment was achieved in all the
eyes when 360° laser retinopexy was performed; in com-
parison, when focal laser was applied, retinal attachment
was achieved only in 76.9% of the eyes11.
Biomed Pap Med Fac Univ Palacky Olomouc Czech Repub. 2018; 162:XX.
4
Operation success was achieved also in patients with
retinal breaks localised in the inferior retinal quadrants. In
48 eyes (38.1%), at least one break was detected between
numbers 4 and 8. Retinal attachment was achieved in all
these patients after the primary surgery. Similar results
were achieved by Duvdevan et al. (ref.16). In their series,
96% (24 eyes out of 25) primary retinal attachment was
achieved in patients with retinal breaks in inferior quad-
rants; compared to 82.4% (28 out of 34) primary retinal
attachment in the eyes with breaks in superior quadrants.
Also, Dell`Omo et al. were very successful in retinal de-
tachment repair in eyes with retinal breaks in inferior
quadrants; retinal attachment was achieved in 92.7% of
the eyes using PPV with gas tamponade without scleral
buckling18.
Proliferative vitreoretinopathy is a frequent cause of
the RRD operation failure12,19. Mini-invasive 25-gauge
vitrectomy causes a mild inflammatory response and a
lower production of pro-inflammatory factors causing
PVR. Despite this, 21% of patients in the group of Lai et
al. developed post-operative PVR (ref.12). In our group, no
patient developed PVR during the postoperative period.
Also other authors reported low PVR incidence13,16 ,18,19 .
Such results may be explained with better fluid dynamics
in the second-generation 25-gauge PPV, when pro-prolif-
erative substances are more meticulously eliminated (e.g.
retinal pigment epithelium cells, growth factors and cy-
tokines).
Sclerotomy leakage with subsequent hypotony became
rather frequent complication of sutureless PPV approach-
es. In our group, it was necessary to suture at least one
sclerotomy in three eyes. On the first postoperative day,
a hypotony under 10 mmHg was detected only in 1 eye
(9 mmHg). The value of IOP returned to normal within
two days without any necessity of further intervention
and without complications. A low incidence of sclerotomy
leakage and postoperative hypotony might be attributed to
extra-oblique scleral incisions. A longer intrascleral tunnel
provides better sclerotomy tightness. Hsu et al. observed a
lower incidence of postoperative hypotony ≤ 5 mmHg af-
ter 25-gauge PPV without tamponade in eyes with oblique
scleral incisions compared to straight sclerotomies (1.8%
vs. 10%) (ref.20). Similarly, Acar et al. observed an inci-
dence of hypotony under 8 mmHg in 17.1% of the eyes
when straight sclerotomies were performed and intraocu-
lar tamponade was not used21. Bourgault, however, did not
prove that oblique sclerotomies decreased the incidence
of postoperative hypotony compared to straight scleroto-
mies both in eyes with gas tamponade or without tam-
ponade (9.9% vs. 9.2%; P=0.85) (ref.22). The application
of gas tamponade, however, markedly decreased the risk
of hypotony (4.8% vs. 20.0% in eyes without tamponade;
P=0.0001). Gas was also used for temporary tamponade
in all the eyes in our group. Gas tamponade generates
pressure on sclerotomies, which contributes to their bet-
ter tightness and speeds up their healing. In our group
of patients with idiopathic macular holes operated with
25-gauge PPV and gas tamponade (n=53), hypotony was
not observed in any eye9. Furthermore, the vitrectomy
without a thorough basectomy leads to a shorter opera-
tion time with minor sclerotomy contusion. This fact may
also contribute to a better tightness of sclerotomies.
CONCLUSION
25-gauge PPV with gas tamponade is an efficient op-
eration technique for the management of non-complicated
retinal detachment including retinal breaks in inferior
quadrants with a minimal incidence of complications.
Extra-oblique sclerotomy incisions minimise the risk of
postoperative hypotony and the necessity to suture scle-
rotomies.
ABBREVIATIONS
PPV, Pars plana vitrectomy; RRD, Rhegmatogenous
retinal detachment; BCVA, Best corrected visual acuity;
PVR, Prolipherative vitreoretinopathy; IOP, Intraocular
pressure; ILM, Internal limiting membrane; ERM,
Epiretinal membrane.
Author contribution: All co-authors contributed equally to
preparing the manuscript. All co-authors also have read
the final manuscript and accept its conclusions.
Conflict of interest statement: The authors state that there
are no conflicts of interest regarding the publication of
this article.
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