Examination |
7 |
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This chapter will neither provide detailed descriptions of examining the patient for VR surgery, nor will it detail the findings in various conditions.1 Instead, a few important, perhaps less commonly emphasized points are presented in Table 7.1 about each diagnostic procedure.
Pearl
The VR surgeon must examine the entire eyeball, not simply the vitreous and retina.
When the examination is completed and the surgeon dictates the findings, it is extremely helpful to do a schematic (retinal) drawing as well.2 I am not recommending a drawing that looks like a piece of art, but a sketch indeed speaks a thousand words: the location and extent of an RD or height of the hypopyon is easy to illustrate and is very informative to a colleague. The drawing also serves as a baseline image for later comparison.
Q&A
Q Does the finding on examination determine the therapy?
ASometimes: an RD makes surgery unavoidable, unless the patient categorically refuses (see Chap. 5). In most cases, however, the diagnosis is the “basis for negotiation” with the patient: whether and when surgery is optimal to be performed.
1Such information can be found in many excellent publications, which the readers are encouraged to consult.
2The iPad with the appropriate software, such as the one being developed by Dr. Klaus Lucke (Bremen, Germany), may be a huge advancement in this area.
© Springer International Publishing Switzerland 2016 |
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F. Kuhn, Vitreoretinal Surgery: Strategies and Tactics,
DOI 10.1007/978-3-319-19479-0_7
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7 Examination |
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Table 7.1 Examining the candidate for VR surgery |
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Variable |
Comment |
History |
The VR surgeon should never rely on the referring physician’s or a nurse’s |
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notes but personally ask the patient about his current complains, past |
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ocular and systemic history, current general condition etc. |
|
Certain conditions such as vitreous floaters may be difficult for the |
|
VR surgeon to visualize, which makes asking the proper questions |
|
especially pertinent |
External |
This is crucial mostly in cases of injury, but can reveal other abnormalities |
inspection |
such as hypopyon or cataracta |
Visual functions |
The VA must be taken in both, not just in the affected eye |
(VA, reading |
In many macular conditions (see Sect. 50.1) the patient’s difficulty reading |
ability, Amsler) |
with the affected eye or the abnormalities found on the Amsler test, |
|
especially if these can be compared to a normal fellow eye’s, are more |
|
important than the VA levelb |
Slit lamp/60–90 |
While such lenses provide a small field of view, they have high |
D lensesc |
magnification and resolution, allowing the surgeon to detect minor |
|
abnormalities in a three-dimensional view. The eye’s external surface, |
|
the anterior chamber and the tissues surrounding/constituting it, the |
|
vitreous/cavity, the posterior retina, the optic disc, and to a certain extent |
|
the choroid can and should be examined |
|
This method is often employed in determining whether a PVD is present. |
|
Unfortunately, what is diagnosed as PVD often proves to be |
|
vitreoschisis (see the comments below, under ultrasonography) |
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The exact location of the retinal break in an eye with RD is much less important |
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to determine if PPV, not SB, is planned (see below and Sect. 54.5.1) |
Slit lamp/ |
The former lens has a very small field of view but allows the surgeon to |
three-mirror |
visualize the chamber angle and the peripheral retina as well. Enlarging |
and/or |
the field of the lens reduces its resolution |
170° lensd |
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IBOe |
This is a great diagnostic tool, which is less utilized today than it deserves. |
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Its strong light is able to penetrate even advanced media opacities, gives |
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an excellent three-dimensional view, and allows dynamic examination. |
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With scleral indentationf, the surgeon can also examine the retinal |
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periphery |
|
Many surgeons stand during the ophthalmoscopy while the patient is |
|
sitting. This does not allow full viewing of the periphery, especially |
|
superiorly, and is very taxing for the surgeon’s lower back. Ideally, the |
|
patient is in the supine position during the examination and the surgeon |
|
is standing over him, with a straight back |
|
The exact location of the retinal break in an eye with RD is much less |
|
important to determine if PPV, not SB, is plannedg |
IOP |
It should always be measured and recorded |
OCT |
This is a relatively new field and an increasingly important diagnostic tool. |
|
Its primary focus is the macular area, but it also provides important |
|
information about the retina elsewhere, the choroid, the optic disc etc. It |
|
allows the surgeon to actually see things that used to be somewhat of a |
|
guesswork beforeh. Being a noninvasive tool, it can readily be used |
|
during repeated follow-up visits, providing the surgeon with a |
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longitudinal view of the condition in question |
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The OCT findings do not always reflect reality. When the diagnosis of |
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PVD, for instance, is made, it may actually be a vitreoschisis – it is the |
|
particular machine’s resolution that limits how much the finding can be |
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trusted (see the comments below, under ultrasonography) |
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(continued) |
7 Examination |
61 |
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Table 7.1 (continued) |
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Variable |
Comment |
Ultrasonography |
This test is very useful in eyes with opaque media, primarily to detect the |
|
presence of an RD. However, it is very important to understand that it |
|
may be impossible to definitely determine whether the retina is detached, |
|
especially in severely traumatized eyes with dense VHi. The surgeon |
|
who, based on ultrasonography, is convinced that the retina is attached |
|
can easily cause major iatrogenic retinal damage during surgeryj |
|
Although it is also often employed to determine whether a PVD has |
|
occurred, ultrasonography can be misleading as it is unable to detect the |
|
thin vitreous layer on the posterior retina. Erroneously diagnosing |
|
vitreoschisis as PVD can lead to erroneous therapeutic decisions |
|
(see Sect. 26.1.2) |
Electrophysiology |
It is extremely rare that the VR surgeon needs the results of this test |
Fluorescein |
It is much less common than in the past that the VR surgeon needs the |
angiography |
results of this test. Nevertheless, this is the only method to show retinal |
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ischemia |
Documentationk |
Drawing, fundus photography, and written and electronic records of all |
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findings can and should be part of the examination (see the text for more |
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details) |
aA nuclear cataract can be highly transparent and therefore easier to detect with a penlight than at the slit lamp.
bThe pathologies causing reading difficulties or metamorphopsia point to foveal involvement, even if the underlying disease is outside the macula. A deep IOFB impact, even if rather distant, can cause retinal folding that reaches into the center.
cThese lenses are noncontact.
dThese are contact lenses and thus should not be used immediately prior to surgery. eKeep in mind that the image the surgeon sees is upside down.
fRemember, this is rather unpleasant to the patient.
gThe advantage of the 90 D lens over IBO in identifying a retinal break and the traction forces acting upon it is its higher resolution; the disadvantage is that it, unlike the IBO, does not allow a proper dynamic examination.
hIs it a partial-thickness macular hole, a pseudohole, or a true hole?
iConversely, in up to a fifth of the cases the presence of an RD is incorrectly diagnosed in an eye with VH (see Sect. 62.1).
jThis is partially a psychological phenomenon. The surgeon is subconsciously prone to proceed with less caution during vitrectomy if under the impression (conviction) that he will not encounter detached retina with his probe.
kThis is not examination in any sense of the world, but should be part of the process of working up the patient.
A final caveat about examining the patient. Do not order tests that will not fulfill at least one of the following criteria:
•Influences therapeutic decisions.
•Serves as a baseline for monitoring progression.
•Helps determining the technique or success of therapy.
•Preserves the record for medicolegal purposes.
•Is necessary for a scientific study.