Biomedical Engineering Reference
In-Depth Information
If the optometrist actually becomes a part of the team, he represents a fundamental asset
for the enhancement of the evaluations and for the achievement of the optimal results,
which otherwise will be slower and based on attempts and errors.
The optimal result may not be achieved starting from the assumption that better results
cannot be reached. This assumption may be generated from the lack of information, for
example, if no one told the team that a patient with a certain limitation in his/her field of
vision could make marked progress by positioning a horizontal monitor on the bottom-left
side of the patient. (This example comes from an actual examination.)
From his/her side, the optometrist who enters this kind of structure for the first time
has to make two important professional efforts. The first one, which is also the easiest one,
is to study all of the various available assistive technologies, work closely with the other
operators, and think of how his/her knowledge can be applied in this kind of scenario,
which is impossible to standardize. The second effort is very complex as well as fascinat-
ing and is linked to the idea that every single patient is special, therefore the whole team
has to make available every possible variation in the standard assessment procedure, get-
ting ready to approach every case in the appropriate way, learning from the patients, and
being flexible in the procedures but at the same time rigid in the objectives. There are not
and there should never be patients who do not cooperate: This is just a simple excuse for
hiding our limitations because every single patient can give us important clues on his/her
visual skills as long as we observe him/her with the right instruments.
10.4 Evaluation of Visual, Perceptive, and
Motor Functions: Clinical Case 1
The child presents a symmetric corneal reflex. At the cover test the answer is ortho. The
child is able to follow slowly by using a normal movement of the head while lying. While
sitting, the child is able to follow even vertically, but she is conditioned by the control of the
head. The evaluation of the refractive state shows hypermetropia that is in the physiologi-
cal range of age. While fixing proximal objects, an adaptive reaction during the retinos-
copy and a sporadic vergence are noticed. The saccadic movements are metrically correct,
but there is a latency of reaction that is higher than the standard. The metric is adequate
until a saccadic width of 20°. The visual acuity, evaluated both through optokinetic reflex
elicitation and preferential look, is 6 c/g.
The young age of the child and the serious neuromotor disease do not allow for a subjec-
tive evaluation of the visual functions. It is therefore necessary to elicit all of the possible
visual answers with variations in dimension and target contrast, even associated with
tactile stimuli or sounds.
The first evaluation made on the child was her fixation ability. The examination of the
corneal reflex of the lightened fixation target was symmetric and centered in both eyes.
Nystagmic movements or lateral shifts were not observed (Traccis 1992). This could sup-
port the hypothesis of binocular vision, not necessarily bifoveal. A further confirmation of
the absence of important phorias or tropias resulted from the cover test. This examination
only requires keeping fixation on a point in space and it was repeated both with the short-
and the long-distance target. In both cases the answer was ortho. This term means that the
shift of the occlusion both in the left eye (LE) and the right eye (RE) did not cause adaptive
