The Highly Myopic Eye |
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42.1The Risk of RD If Cataract Surgery Is Needed
One crucial question in these patients is the development of a cataract, whose removal further increases the RD risk: what is the safest management option? There are three alternatives to choose from:
•The traditional approach. Standard phacoemulsification and IOL placement are performed, even if the IOL has 0 D power (see Table 3.3). This option completely neglects the RD risk.1
•The traditional approach + laser cerclage. At least 1 month before the cataract is removed, the anterior retina is treated (see Sect. 30.6) to counter the existing and forthcoming traction. The problem is that the cataract may interfere with visualization and thus the completion of the treatment; furthermore, the laser scars may not be sufficient to resist the VR traction. Nevertheless, this option reduces the RD risk compared to the traditional approach.
•The unorthodox approach: lensectomy, vitrectomy, and endolaser cerclage. This is by far the most complex operation and one with an obvious risk for postoperative PVR development. However, once the PVR threat is over,2 the risk of RD will be as close to zero as possible. IOL implantation may not be needed at all,3 but if an IOL is implanted, the surgeon should consider the option of removing the capsules and implanting an iris-claw IOL (see Chap. 38).
1The problem is the VR surgeon’s.
2~3 months postvitrectomy (see Sect. 53.1).
3If the aphakic status yields an emmetropic situation or one close to it.
© Springer International Publishing Switzerland 2016 |
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F. Kuhn, Vitreoretinal Surgery: Strategies and Tactics,
DOI 10.1007/978-3-319-19479-0_42
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42 The Highly Myopic Eye |
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42.2Vitrectomy in the Highly Myopic Eye
The larger axial length has important implications for the VR surgeon (see
Table 42.1).
Table 42.1 The highly myopic eye and the VR surgeon
Findinga |
Comment |
Axial length too large for some |
Especially the probe; in eyes over 32 mm it is either |
instruments |
impossible to reach the posterior pole or the eyewall must |
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be significantly indented. This can distort the image and |
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make the creation of a PVD even more difficult |
Blood circulation poorer |
May be an additional reason for the increased RD risk and |
(contributory factor in retina |
may explain why permanent visual deterioration can occur |
and choroid becoming |
earlier if the macula detaches |
thinner) |
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Eyewall too thin |
Easier to inadvertently penetrate with a needle during |
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peribulbar anesthesia or SBb |
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Postoperative thinningc with bluish discoloration of the sclerad |
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is not uncommon |
ILM peeling |
More difficult and risky because the retina is so much thinner |
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and because the loss of pigment in the RPE may mean |
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lower contrast even if the staining is successful |
IOL implantation |
May be unnecessary if the refractive error does not need |
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correction (see the text and Sect. 38.4.2) |
Laser cerclage |
Regardless of the etiology/indication for PPV, such laser |
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should always be considered to reduce the risk of |
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postoperative RDe |
Lens: anterior displacement |
Removal of the anterior hyaloid face may become technically |
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easier |
PVD |
See above. Particularly in eyes with RD the surgeon must |
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struggle with, but not give up on, the creation of a PVDf |
Sclerotomy site |
Should be a bit more posterior (~4 mm) |
Staphyloma – spanning RD |
See Chap. 56 |
aIn alphabetical order.
bCreating scleral tunnels for fixing the band is contraindicated in these eyes (see Sect. 54.4.2.6). cEspecially after reoperations, and particularly, but not exclusively, in 20 g surgery.
dObviously, this is the choroid’s color, which becomes visible through the thin sclera.
eIn fact laser cerclage should also be considered if the eye undergoes cataract extraction; removal of the lens adds a second risk factor for postoperative RD development (see the text for more details).
fI have never seen a highly myopic eye with a complete spontaneous PVD; they all have a vitreoschisis, although it may be very difficult to visualize the vitreous cushion on the posterior retina, even intraoperatively and even with TA use (see Chap. 56).
42.3Posterior RD over a Staphyloma
This is detailed in Chap. 56.