Ординатура / Офтальмология / Английские материалы / A Visual Field Evaluation with Automated Devices 2nd edition_Reddy_2006
.pdf
VISUAL FIELD TESTING WITH FREQUENCY DOUBLING TECHNOLOGY 191
HUMPHREY MATRIX 24-2 VISUAL FIELD PRINTOUT
Selection of the test : 24-2 FDT threshold Reliability indices : Good
Mean deviation : –12.13 dB P < 0.5% PSD : +6.29 dB, P < 0.5%
GHT : Outside normal limits
Total deviation probability plot and pattern deviation plot are almost symmetrical showing abnormal areas on either side of the vertical axis.
11Visual Field Defects Due to Occlusive Vascular Disorders of the Visual Pathway, A Case of Bitemporal Hemianopia and Coloboma of Disc and Retina
In this chapter I am presenting six cases of visual field defects of clinical importance. The first four cases are due to occlusive vascular disorders to the visual pathway.
Case - I Page No. 193 |
Anterior ischemic optic neuropathy (AION). |
Case - II Page No. 194} |
|
Case - III Page No. 195 |
Occlusion of upper branch of central retinal artery. |
Case - IV Page No. 196 |
Right posterior cerebral artery occlusion. |
Case Histories
Case I and Case II: Both these patients are known diabetic. Presented with defective vision in their left eyes.
Fundus: Both eyes showed pale disc edema with background diabetic retinopathy. Visual fields of the both the patients showed altitudinal field defects (Page no. 193 and 194). Pale disc edema and altitudinal field defects are suggestive of anterior ischemic optic neuropathy (AION). Later the diagnosis was confirmed by FA.
Case III: Complaint: Difficulty while walking down the steps. Left eye fundus: showed occlusion of the upper branch of central retinal artery.
Visual field: Lower half of the field defect with fovea sparing (Page No. 195).
Case IV: Complaint: Ataxic gait, funduswithin normal limits. FieldField showed left homonymous hemianopia (Page No. 196).
Diagnosis: Right posterior cerebral artery occlsion. Later the diagnosis was confirmed by CT scan brain. which showed right occipital lobe infarct.
CASE V: Complaint – unable to appreciate the side vision – OU.
OU - Fundus revealed mild palor of the optic disc especially the nasal side of the disc. Fields showed bitemporal hemianopic defect.
CT brain showed ? Anterior communicating artery aneurysm (Page No. 197). CASE VI: Case of coloboma of lower half of the disc and retina (Page No. 198).
VISUAL FIELD DEFECTS DUE TO OCCLUSIVE VASCULAR DISORDERS 193
SINGLE FIELD ANALYSIS PRINTOUT OF AION (CASE NO.1)
Selection of the test |
: 24-2 SITA Standard |
Reliability |
: Good |
Total deviation |
: Upper horizontal field defect |
Pattern deviation |
: Upper horizontal field defect |
PSD |
: 13.06 dB P value < 0.5% |
Mean deviation index |
: – 11.62 dB P value < 0.5% |
Interpretation |
: AION (fields are suggestive of anterior ischemic optic neuropathy - |
|
corresponding to the disc appearance). |
194 A VISUAL FIELD EVALUATION WITH AUTOMATED DEVICES
SINGLE FIELD ANALYSIS PRINTOUT OF AION (CASE NO.2)
Selection of the test |
: 24-2 SITA Standard |
Reliability |
: Good |
Total deviation |
: Lower horizontal field defect |
Pattern deviation |
: Lower horizontal field defect |
PSD |
: 14.12 dB P value < 0.5% |
Mean deviation index |
: – 13.95 dB P value < 0.5% |
Interpretation |
: AION (fields are suggestive of anterior ischemic optic |
|
neuropathy - corresponding to the disc appearance). |
VISUAL FIELD DEFECTS DUE TO OCCLUSIVE VASCULAR DISORDERS 195
SINGLE FIELD ANALYSIS PRINTOUT OF OCCLUSION OF
UPPER BRANCH OF C.R.A. (CASE NO.3)
Selection of the test |
: 24-2 SITA Standard |
Reliability |
: Good |
Total deviation |
: Lower horizontal field defect and fews scotomas in the upper horizontal field |
Pattern deviation |
: Lower horizontal field defect |
PSD |
: 14.88 dB P value < 0.5% |
Mean deviation index |
: – 18.19 dB P value < 0.5% |
Interpretation |
: Occlusion of upper branch of CRA |
|
(Field defects are corresponding to the fundus changes). |
196 A VISUAL FIELD EVALUATION WITH AUTOMATED DEVICES
SINGLE FIELD ANALYSIS PRINTOUT OF RIGHT POSTERIOR
CEREBRAL ARTERY OCCLUSION (CASE NO.4)
RIGHT EYE |
LEFT EYE |
Left Homonymous Hemianopia
Case IV: Complaint: Ataxic gait funduswithin normal limits. FieldField showed left homonymous hemianopia.
Diagnosis: Right posterior cerebral artery occlusion. Later the diagnosis was confirmed by CT scan brain, which showed right occipital lobe infarct.
VISUAL FIELD DEFECTS DUE TO OCCLUSIVE VASCULAR DISORDERS 197
FIELD CHART OF BITEMPORAL HEMIANOPIA
LEFT EYE |
RIGHT EYE |
Bitemporal Hemianopia
In this case I am showing bitemporal hemianopia. The CT showed a big aneurysm pressing the central fibers of optic chiasma. The aneurysm is thought to be arising from Anterior communicating artery.
198 A VISUAL FIELD EVALUATION WITH AUTOMATED DEVICES
SINGLE FIELD ANALYSIS PRINTOUT OF COLOBOMA OF
LOWER HALF OF THE DISC AND RETINA
The field defect is corresponding to the coloboma of the fundus. The student should not be blamed if he says “ I’m seeing a localized field defect in the upper arcuate area most probably due to glaucomatous optic nerve damage” when he is not given the fundus picture. From this case, one should understand how important is to correlate the fields with the fundus picture.
12Important Clues in Operating
Humphrey Field Analyzer
In order to fill the main menu of the Humphrey field analyzer we have to know the available tests in the Humphrey field analyzer. So, I am here with giving the available tests of Humphrey field analyzer.
Humphrey visual field tests
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Threshold tests |
|
|
|
|
|
Screening tests |
|||||
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Central tests |
Peripheral tests |
Special tests |
|
|
|
|
|
|
|
|
|
|
|
Glaucoma tests |
|
Central tests |
|
Full field tests |
|
Peripheral tests |
||||
|
|
|
|
|
|
|
|
|
|
|
This is a broad classification chart of Humphrey field tests. Again each group contains a number of different test point patterns and each test can be conducted with different test strategy.
200 A VISUAL FIELD EVALUATION WITH AUTOMATED DEVICES
The three broad groups of the threshold test are again subdivided according to the test point pattern and their location.
THRESHOLD TESTS
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Central |
|
|
|
|
Peripheral |
|
|
|
|
Speciality |
|
|||||
|
tests |
|
|
|
|
tests |
|
|
|
|
tests |
|
|||||
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Central |
30-2 |
Peripheral |
60-4 |
Neurological |
20 |
Central |
24-2 |
Nasal step |
|
Neurological |
30 |
Central |
10-2 |
Temporal crescent |
|
|
|
Macular program |
|
|
|
|
|
Each of the above test can be conducted with
any of the threshold - strategies.
(Full Threshold, FASTPAC, SITA-Standard or SITA-Fast).