Tuesday, November 11, 2008

PSP current nomenclature and types

"The postmortem room has become the temple of truth" (Donald Calne, re PSP) (Neurology 2008)

Current nomenclature "Richardson disease" corresponds with initial descriptions. There is a gradual onset of postural instability and falls within the first two years, with vertical supranuclear gaze palsy, a frontal dysexecutive syndrome, rigidity and bradykinesia that is not responsive to leveodopa, and a life expectancy of six years.

A second milder group at pm (post-mortem) have PSP tau pathology that is more restricted and less severe are called PSP-P (PSP-parkinsonism). They have assymmetric bradykinesia of the limbs, an initial response to levodopa, tremor and limb dystonia without early falls, eye movement problems, or cognitive dysfunction. Most patients with "atypical PSP" are in this category.

The third rarer category is pure akinesia with gait freezing (PAGF). There is gradual onset of unsteady or slow gait and hypophonia progressing to gair freezing and start hesitation, without limb rigidity or tremor. There is no response to levodopa and there is no dementia or opthalmoplegia in the first five years. In types 2 and 3 the median duration of the disease is around ten years.

Other patients with similar tau-PSP pathology present with corticobasal ganglionic degeneration, progressive nonfluent aphasia, or apraxia of speech.

Practice pearl:  pay attention to SPEED of vertical saccades

 References up to date: Williams DR, de Silva R, Pavour DC et al. Characteristics of two distinct clinical phenotypes in pathologically proven progressive supranuclear palsy: Richardson' syndrome and PSP - parkinsonism. Brain 2005; 128:1247-1258. Williams DR, Holton JL, Strand C. et al. Pathological tau burden and distribution distinguishes progressive supranuclear palsy-parkinsonism from Richardson's syndrome. Brain 2007; 130: 1566-1576. Mizusawa H, Mochizuki A , Ohkoshi N, et al. Progressive supranuclear palsy presenting with pure akinesia. Adv Neurol 1993; 60: 618-621. Josephs KA, Duffy JR, Strand EA et al. Clinicopathological and imaging correlates of progressive aphasia and apraxia of speech. Brain 2006; 129: April 13. Tsuboi Y, Josephs KA, Boeve BF et al. Increased tau burden in the cortices of progressive supranuclear palsy presenting with corticobasal syndrome. Mov Disord 2005; 20: 982-988.
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Tuesday, November 04, 2008

Horners syndrome pearls

Note-skipping standard textbook items, this is a(my) blog and I am ONLY including minutiae that I want to remember later and am purposely omitting much common information about horner's that is already well known to me. This post is based on H Wilhelm, "The Pupil" Curr Opin Neurol 21:36-42 2008.

1. Many cases of Horners after evaluation remain idiopathic.
2. Iatrogenic Horners after subclavian/jugular venous puncture is fairly common and well reported
3. Carotid dissection is associated with 25 or 37 % Horners s., and the key clinical pearl is the association of PAIN and acuity. 15 % have a bad outcome so beware of this diagnosis.
4. Beware of VI paresis and Horners which usually localizes to cavernous sinus and indicates a mass lesion there.
5. Previously unknown mediastinal tumors are RARE. Only two percent of bronchogenic tumors are Pancoast tumors . Other tumors that RARELY present are thyroid (usually benign goiter but could be CA) and nasopharyngeal CA.
6. In children neuroblastoma is fairly common and needs to be ruled out. rhabdomyosarcomas and gangliogliomas also are reported in this population.
7. Cocaine testing in texts is difficult to the trouble getting cocaine drops. Apraclonidine can be an effective substitute. Like cocaine, the pupil is only denervated in the third neuron in the arc and only such third neuron lesions dilate with apraclonidine. It does reverse anisocoria in such cases. The jury is truly not back in for apraclonidine. More studies are indicated.
8. To differentiate meiosis in Horners from physiologic anisocoria, check time to dilatation in darkness. Infrared video can be used if available. Normal pupils start to filate by .5-1 s and reach maximal dilatation by 5 s, whereas Horner pupils reach maximal dilatation by 10 seconds. Its only sensitive if repeated about four times; if only done once, it will most likely be false negative, if done four times, is 83 % sensitive.

More facts about Horner's
9. Reported after chest tube insertion
10. reported after cervical block/epidural
11. Klumpke's paralysis, goiter,MS sympathectomy, chiari, lateral medullary infarct,acute otitis, mandibular abscess, neuroblastoma,and cervical rib are other causes
12. Signs may include loss of ciliospinal reflex, heterochromia (iris)
13. In animals leashes if too tight can cause Horner's syndrome
14. Drugs are overlooked cause esp drugs that affect DA levels
14. Sweating pattern analyzed by Morris lee and Lim:
The distribution of sweating on the face was studied in 31 patients with Horner’s syndrome. In patients whose lesion was known to be distal to the bifurcation of the common carotid artery impairment of sweating was confined to the medial aspect of the forehead and side of the nose. In more proximal lesions loss of sweating involved the whole of one side of the face. Facial sweating was normal in 6 patients with avulsion injuries of the brachial plexus and in 2 patients with a lateral meduliary syndrome. These findings suggest that the pattern of sweating in Horner's syndrome may be useful in some patients in localizing the site of the lesion. (Brain, 1984)

Oculomotor syndromes PEARLS

cf Tilikete C, Pelisson D. Oculomotor syndromes of the brainstem and cerebellum. Curr Opin Neurol 21:22-28 2008

Head shaking nystagmus (hsn)- usually is a peripheral vestibular lesion. However it can occur in Wallenberg syndrome.

In central positional nystagmus, Dix Hallpike testing induces downbeat nystagmus(DBN). DBN also occurs in floccular disturbance and the gravity dependent component can be suppressed with 3,4 aminopyridine. Other oddball causes of DBN include West Nile virus encephalomyelitis, intrathecal morphine, a particular genetic syndrome of cerebellar ataxia, or another syndrome combining DBN with motor neuronopathy and cerebellar ataxia.

Saturday, November 01, 2008

Abnormalities (hemorrhages etc.) conjunctiva-causes

1.Subconjunctival hemorrhages-- common in trauma, rare in SAH and severe HTN
2. Leptospirosis-- injection of conjunctiva plus meningitis and myopathy
3. Filarial migratory phase of loa-loa-- injection is seen
4. telangiectasia in conjunctiva seen in sickle cell disease and ataxia telangiectasia
5. Retroorbital tumors can produce injection
6. Renal failure can produce severe conjunctival injection

Hypertelorism-- list of causes

1. normal
2. congenital absent callosum
3. Aicardi's syndrome
4. Schapiro's syndrome ( hypothermia and other congenital defects)
5. Septo-optic dysplasia