Microsoft Word - Editorial 24,2,08


53 

Editorial 
 

Management of Retinal Detachment 
According to Risk Factors 

 
Retinal detachment is a sight threatening and 
potentially blindening condition which if treated 
promptly can save and salvage good vision. On the 
other hand, in spite of prompt and timely surgery 
sometimes the visual outcome is not up to our 
expectations. These things pose a problem especially 
in our society where economics play a major role. 
There is very limited medical insurance for private 
sector and public sector is inundated with huge 
numbers. The number of VR surgeons is certainly 
insufficient to cope with the amount of patients and 
there is an obvious and dire need for more facilities to 
perform these surgeries. In this scenario we need to 
have some basis upon which we can build our 
decisions and expectations so that our system becomes 
more efficient with best possible results. There have 
been two good efforts recently in the form of studies 
done in Pakistan, the first one to find out about the 
Risk factors for developing PVR which eventually will 
predict the surgical outcome and the second about 
different presentations, their management and results. 
These efforts are extremely useful and give the idea of 
what kind of patients we are dealing with and at the 
same time some insight into our surgical management. 
They have shown for example that a retinal 
detachment of 1 month duration is a very significant 
landmark as a prognostic factor for PVR. On the other 
hand there are some concepts which require special 
attention. I would like to try and clarify some points 
from one of the studies which otherwise may create 
some confusion for others. 

 
Some concepts of the study: 

a. The study gives an impression that there could 
have been some confusion between the diagnosis 
of a dialysis and a GRT (Giant Retinal Tear). The 
basis of my presumption is the fact that in their 
study all the dialysis had PVR which had 
developed within two weeks, they were dealt in 

by vitrectomy and they all had bad visual 
outcome. Why? This compels us to look more 
carefully into the situation. 

b. Second is a concept of leaving the oil in 
permanently. Some believe that as silicone oil has 
not shown any problem for 6 months (period of 
their follow-up) therefore it will never do so in the 
future and can be left safely in the eye indefinitely. 

c. It was also stated that patients develop cataract in 
a GRT. 

d. There were genuine concerns about anterior PVR 
which became a major factor resulting in failure of 
surgery, without any possible solution. 

e. One very interesting comment about their 
technique was that cryo was applied in 2 rows 
only posterior to the breaks. 

f. It has been quoted that Silicone oil has better 
retinal attachment rate than SF6. 

 
The visual results in our local study are not up to 

the mark, so we will have to look into it in detail to see 
whether the results were as expected or not. The 
dialysis which were treated; were either not dialysis 
but GRTs or if they were dialysis then the surgical 
management should have been different. Dialysis is 
usually (not always) a result of blunt ocular trauma 
where by the peripheral retina is torn or avulsed at the 
edge. There is a roof of vitreous base over the defect 
therefore, much less RPE cells will trickle over into the 
vitreous cavity resulting in much less PVR. That is 
why the procedure of choice for a dialysis is Cryo / 
Buckle and/or drain. Best form of external temponade 
is a sponge for a dialysis but then personal preferences 
are justified. We know that if we do a vitrectomy on a 
dialysis then there is a danger of it being converted to 
a GRT along with all the sequelae. 

As for the duration of silicone oil (SO), the reality 
is that oil seldom causes any problem before 6 months. 



54 

1000 to 1300 CST SO is supposed to last about 6 to 8 
months after which it is usually removed; whereas, the 
5000 CST is usually good for over 5 years. Variations 
are always there. We are aware of the controversy 
about silicone oil being toxic to the retina at times, 
therefore where ever possible it should be removed. 
However, there will be cases where we have to leave it 
for as long as possible. Cataract which is seen after a 
GRT is usually because of the surgery and silicone oil. 
One belief is that oil will provide better temponade 
than the gas but the basis of this has been doubtful as 
gas was not tried at all in their study. It is the opinion 
of many authorities that gas can provide better 
temponade; it’s the reduction of size rate versus 
longevity of oil which makes the difference. The 
relative advantages of the oil include clear media in 
the post operative period which can help an only eye 
patient to cope and the surgeon to perform laser in 
some situations. It can also provide long term 
temponade. Where as gas does not require a separate 
procedure for removal and cause less cataracts. 
Indeed, we see a predominant trend here towards not 
using the intravitreal gases with vitrectomy as 
compared to the developed world. Superior breaks 
can easily be covered with gas (SF6 or C2F6) even 
without any external support. In case of inferior break 
also; gases like C3F8 can be sufficient but usually with 
external temponade and proper post-op posturing. 
One very important message that I would like to pass 
here is about cryo. It should cover all the edges, as 
fluid can go around from anterior side. As rightly 
stressed by the author we should not freeze the 
exposed base in the middle of the hole as it can release 
RPE cells and cause PVR. We also have to be careful 
not to apply cryo twice at one spot as it can later cause 
necrosis and breaks. The freeze ball should only come 
to the edge of the break. 

Books have taught us how far back to place our 
encircling bands and we may modify it according to 
our needs. We know that the purpose of a 360 degree 
band is not to cover the holes but to support the 
vitreous base and can also be used to counteract the 

PVR forces. When placed posteriorly these bands 
produce a barrage between the anterior and posterior 
retina so that the posterior retina stays relaxed and 
flat. But, when we encounter anterior PVR our 
placement of band should be anteriorly to counter act 
that force. 

Inferior PVR and later tractional redetachments 
have haunted our surgeons for quite some time. Once 
developed, it has to be countered by inferior relaxing 
retinotomies or even retinectomy, but liquids like 
heavy silicone can also help avoid these problems. 
However, the cost of this is higher and it has to be 
removed within 3 months. Second option is 360 degree 
band or inferior high external temponade along with 
silicone oil and proper post-operative posturing. 
Trauma and penetrating injury causes high level of 
PVR therefore, it is useful to consider anti proliferative 
agents like intravitreal triamcinolone and infusions 
containing heparin and 5FU to flush the vitreous 
cavity, just like in a macular translocation surgery. 

The responsibility lies with us ophthalmologists 
who are doing or are interested in doing retinal 
surgery to get as much training as possible in this field 
and to keep up to date with the newer developments 
to perform safe surgery. We should also try to follow 
basic rules laid down by the pioneers to deal with 
cases according to their risk factors. One such basic 
rule in the treatment of retinal detachment is, “Do it 
from the outside as far as possible”. The common 
exceptions are: Most aphakic and pseudophakic 
detachments, PVR with tightening, too far posterior 
multiple breaks etc. One of the most important factors 
in deciding whether to do an external procedure or a 
vitrectomy is presence or absence of a PVD (Posterior 
vitreous detachment). And remember one thing, “PVR 
is often a result of failed surgery rather than a cause 
for it“. 
 
 

Khurram A. Mirza