Download Nguyen, T

Alexia: Low Vision Masquerader
AbstractAlexia is a reading disorder that can occur after a stroke. This case presents a patient with alexia
following a stroke, masquerading as difficulty reading due to moderate low vision from wet macular
degeneration.
I. Case History
 Demographics: 83 year old Caucasian male
 Chief complaint
o Patient referred for low vision exam with inability to read small print
o Main goals for low vision rehabilitation/activities of daily living (ADL)
 Reading
 Signing name
 Seeing dials on radio
 Seeing numbers on TV remote and telephone, computer keyboards
 History
o Ocular
 Exudative macular degeneration OD, s/p Anti-VegF injections
 Non-exudative macular degeneration OS
 Pseudophakia OU
 Diabetes Type II without retinopathy OU
 Grade 1 hypertensive retinopathy OU
 Posterior vitreous detachment OU
o Medical
 Vascular dementia
 Cerebrovascular accident (CVA) x three incidents
 Initially, unable to recognize letters, relearned using flashcards
 Knows numbers
 Remembers music/hymns
 No difficulty speaking
 Walking: uses cane occasionally for balance, and wife helps
 Right-sided weakness
 H/o hallucinations
 Diabetes mellitus type II
 Peripheral neuropathy
 Gastroesophageal reflux disease
 Hypertension
 Degenerative joint disease of the spine
 Medications
o Valproic Acid 250mg Cap PO BID
o Escitalopram oxalate 5mg tab 2 tab PO QD
o AREDS 2 Vitamins
o Atorvastatin Calcium 20mg half tab QD
o Cephalexin 500mg Cap PO TID
o Dabigatran Etexilate 150mg Cap PO BID
o Sertraline HCL 100mg half tab PO QD
o Sotalol HCL 160mg half tab PO BID
o
Trazodone HCL 50mg tab PO QPM
II. Clinical Findings: Low Vision Evaluation
 Best Corrected Distance VA:
o OD: +2.00-3.00x090 2M/4+2
o OS:+1.50-3.00x100 2M/5+1
 Contrast sensitivity: OU: 1.50, slight impairment
 Amsler @ 33cm
o OU: Full, (-) metamorphopsia, (-) scotoma
o OD: Full, (+) metamophopsia, (-) scotoma
o OS: Full, (-) metamorphopsia, (-) scotoma
 EOM: full range of motion
 Pupils: PERRL (-) APD
 CVF: FTFC OD, OS, OU
 Near low vision Assessment
o Calculated ADD: +3.00
o Device evaluation
 Pt had difficulty reading with appropriate magnification
 Bar magnifier, can read letters, but has trouble stringing letters together to form
a word
 Increased magnification ~10 fold on CCTV, and was able to read letters and
sound out the word “elephant,” but reads it as “ele pant” with significant
difficulty
o Ocular Health
 SLE: unremarkable
 Un-dilated Fundus Examination (90D)
 Macula: pigment clumping OU
III. Differential diagnosis
 Primary/leading
o Low vision due to exudative ARMD OD, non-exudative ARMD OS
 Patient has reduced vision due to macular degeneration causing inability to see
small print.
 Patient was able to see letters with magnifiers, but not form words. This
indicates that there is some neurological defect causing inability to read.
o Alexia
 Patient able to read letters, but not form words with magnifying devices.
Patient has history of three strokes with right-sided weakness. Patient had to
relearn letters with flashcards.
IV. Diagnosis and Discussion
 Diagnosis
o Alexia following cerebral vascular accident
 Discussion
o Alexia is an acquired reading disorder that occurs after a person has established the
ability to read. Alexia can cause difficulty with:
 Recognizing words
 Reading synonyms
 Reading small words like “it” or “the”
 Extended periods of reading
o
Alexia is categorized into two main groups:
1. Central alexia
 Phonological alexia- can read familiar words, but have trouble with new words.
Nouns and words that they have had increased exposure to are easiest for these
individuals to read, but sounding out words proves very difficult.
 Deep alexia- includes semantic errors such as confusing the word “cat” with
“dog” in addition to all the phonological symptoms.
 Surface alexia- the opposite of phonological alexia. It is diffiicult for these
individuals to read words they recognize but they still have the ability to sound
out unfamiliar words.
2. Peripheral alexia
 Hemianopic alexia- the most common type of peripheral alexia. In this category,
the visual field loss from a stroke can come close enough to fixation that it
interferes with the saccades that are necessary for reading.
 Pure alexia- individual letters are easily recognized, but it is difficult to read
single words. In order for a patient with pure alexia to read, they must break
down the word into letters, then re-assemble them back into a word.
 Neglect alexia- prefixes are missed or substituted with another prefix.
 Attentional alexia- letter crowding, migration, and blending of words occur.
V. Treatment/Management
 There are few studies that report clear effects of therapy with alexia. There are no reports of
controlled data or reported findings that are supported by statistical data.
 The role of neuroplasticity in the treatment of alexia has shown some improvement in some
case studies.
 Multiple oral re-reading techniques have some effect.
o In pure alexia, the focus of therapy is primarily on recognizing whole words.
o Hemianopic alexia therapy attempts to improve saccadic eye movements.
VI. Conclusion

Neurological defects should be considered along with visual defects in providing a complete low
vision examination.
Bibliography
1. Leff, A. P., G. Spitsyna, and R. J. Wise. "Structural Anatomy of Pure and Hemianopic Alexia." Journal
of Neurology, Neurosurgery & Psychiatry77.9 (2006): 1004-007. Web. 26 Aug. 2015
2. Leff, Alexander. "Alexia." Advances in Clinical Neuroscience and Rehabilitation 4.3 (2004): 18-22.
Whitehouse Publishing, 7 Alderbank Terrace, Edinburgh. Web.
3. Starrfelt, Randi, Rannveig Rós Ólafsdóttir, and Ida-Marie Arendt. "Rehabilitation of Pure Alexia:
A Review." Neuropsychological Rehabilitation 23.5 (2013): 755-79