This medical journal article reviews ocular motility issues in aging and dementia, and includes PSP, CBS, and DLB among others (AD, PD, FTLD, CJD).
Here’s a link to the abstract:
Ocular Motility of Aging and Dementia
Pelak VS.
Current Neurology and Neuroscience Reports.
2010 Aug 10. [Epub ahead of print]
PubMed ID#: 20697981
I’ve copied below a few excerpts related to three disorders within Brain Support Network — PSP, CBS, and DLB.
Robin
Excerpts from:
Ocular Motility of Aging and Dementia
Pelak VS.
Current Neurology and Neuroscience Reports.
2010 Aug 10. [Epub ahead of print]
PubMed ID#: 20697981
Dementia with Lewy Bodies
Ocular Motility Dysfunction
Systematic study of eye movements in DLB has been very limited. … Reflexive saccades are impaired in DLB, with increased latencies and antisaccades errors. Vertical and horizontal supranuclear palsies are rare but have been described. Balint syndrome may be prominent because of involvement of the biparietal cortex.
Visual Symptoms
Visual hallucinations are the most common visual complaint, but reading difficulties, difficulty focusing, and other visual complaints similar to those in both AD and PD…may occur.
Corticobasal Syndrome
Ocular Motility Dysfunction
The most prominent disturbance is increased saccade latency, which is greater for saccades toward the direction of limb apraxia and correlates with limb apraxia scores. On examination, some patients may use head thrusts to improve horizontal saccades. Convergence insufficiency and a high number of errors on the antisaccade test also may be observed. Vertical and horizontal gaze palsies and/or ocular misalignment may occur, but rarely to the significant extent seen, for example, in PSP.
Visual Symptoms
Patients may report difficulty reading, likely
because of problems moving their eyes from word to word and from line to line in the presence of severely increased saccade latency. If ocular misalignment or convergence insufficiency is present, patients will report diplopia.
Progressive Supranuclear Palsy
Ocular Motility Dysfunction
The diagnostic ocular motility hallmark is
limitation of vertical gaze, usually downgaze
before upgaze. Involvement of horizontal gaze typically follows. Supranuclear gaze palsies may appear months or years after the onset of other neurologic symptoms, and they usually are preceded by marked slowing of voluntary vertical saccades. Horizontal saccades also may be markedly abnormal with decreased saccade amplitude and velocity, whereas latency often is normal. Saccadic gain and smooth pursuit gain are significantly decreased… An increased frequency of square wave jerks is seen in 60% of PSP patients, and these are readily notable during fixation.
Visual Symptoms
Difficulty reading is an especially prominent
complaint because of the downgaze palsy. Diplopia is relatively uncommon because the gaze palsy usually is symmetric. Blurred vision and eye discomfort occur, and these symptoms more likely are related to decreased blink rate and inadequate tear production than to ocular motility disturbances; however, fixation instability and impaired convergence also may contribute.