AUTHOR AND EDITOR INFORMATION

Section 1 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• References

INTRODUCTION

Section 2 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• References

Background

Cortical basal ganglionic degeneration (CBGD) may be considered a syndrome rather than a disease. Its defining clinical characteristics (ie, progressive dementia, parkinsonism, limb apraxia) may occur as a result of heterogenous neuropathological conditions such as Pick complex disorders (see Pick Disease), Alzheimer disease, and even rare disorders such as CNS Whipple disease and Niemann-Pick type C. Histopathologically identifiable CBGD can also present clinically as primary progressive aphasia or primary progressive apraxia in patients who had no prominent movement disorders earlier in their lives.

Pathophysiology

Both cortical and subcortical abnormalities are seen. Ballooned swollen neurons with loss of cytoplasmic staining (ie, achromasia) are present in the cortex and also may be seen in the basal ganglia. As in Pick disease and progressive supranuclear palsy, tau-immunoreactive neuronal and glial inclusions may be seen in cortical (pyramidal and nonpyramidal) neurons as well as subcortical regions. However, inclusions in CBGD, unlike Pick bodies, are not immunoreactive to ubiquitin.

Frequency

United States

Data on incidence and prevalence of this disorder are still being collected. Clinical reports have multiplied geometrically in the last 20 years, suggesting either that clinical evaluation has become more sensitive or that the syndrome is appearing more frequently. It is estimated to account for less than 3% of cases of parkinsonism seen in clinics that specialize in movement disorders.

Mortality/Morbidity

This is a progressive neurodegenerative disorder with increasing levels of disability and loss of independence. Individuals with CBGD do not usually die of the disorder itself but of complications of the bedridden state, such as aspiration pneumonia and infections.

Race

No racial predilection is known.

Sex

No sexual predilection is known.

Age

Typically, CBGD presents in the sixth or seventh decade of life. No pathologically confirmed case of CBGD has ever had its onset at an age younger than 45 years.

CLINICAL

Section 3 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• References

History

Lang proposed the clinical criteria for diagnosis of cortical basal ganglionic degeneration (CBGD) (enumerated here with some revisions); it usually is accompanied by the pathology of cortical basal ganglionic degeneration.

• Chronic progressive course
• Asymmetric onset of extrapyramidal dysfunction
• Higher cortical dysfunction
• • Limb apraxia - Disorder of skilled, learned, purposeful movement; this is one of the few disorders in which limb apraxia can appear in the history (ie, patients are often aware of the apraxia).
  • "Alien limb" ("My hand/leg has a mind of its own.")
• Movement disorder
• • Rigid/akinetic syndrome resistant to therapeutic doses of levodopa
  • Dystonic limb posturing (not purely action induced)
  • Spontaneous and reflex focal myoclonus
  • According to Fahn, occasional action tremor
• Unusual presentations, for example, primary progressive aphasia and progressive buccofacial apraxia
• Prominent delusions or hallucinations (not related to levodopa): These suggest that the patient does not have CBGD; they are more characteristic of diffuse Lewy body disease.

Physical

• Limb apraxia: Patients must make errors beyond using a body part as a tool (eg, using fingers as scissor blades). Errors often suggest ideomotor or limb-kinetic apraxia.


• Other mental abnormalities include the following:
• • Amnesia
  
  
  • Generally, no "cognitive" abnormalities (eg, right-left disorientation, naming difficulty, acalculia), but rather "frontal-executive" deficits (eg, distractibility, perseveration, loss of judgment, motor planning deficit even on the less motor-impaired side)


• Eye movements: These can be impaired, with restricted horizontal movements as well as upgaze; restricted downgaze is suggestive of progressive supranuclear palsy.


• Dystonia: This is not purely action induced.


• Myoclonus: Myoclonus must spread beyond fingers if stimulus sensitive.


• Rigidity: This must be elicited easily without reinforcement.


• No resting tremor is present.


• No autonomic disturbance is present.


• Cortical sensory loss: Loss of graphesthesia (ability to identify a letter drawn in the hand or on the finger) can be a sensitive test.

Causes

• The cause of CBGD is unknown.
• Case reports suggest that a familial predisposition may exist in some individuals with this disorder.
• Because of the clinical and pathologic relationships between CBGD, progressive supranuclear palsy, and Pick disease, interest in this disease has focused on chromosome arm 17q markers. At this point, however, no definite relationship between genetic markers in this region and CBGD has been demonstrated.

DIFFERENTIALS

Section 4 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• References

Other Problems to be Considered

Dentatorubropallidoluysian atrophy
Drug-induced parkinsonism
Progressive pallidal atrophy
Vascular dementia

WORKUP

Section 5 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• References

Lab Studies

• Ceruloplasmin - Also performed in patients with atypical parkinsonism or Parkinsonlike syndrome
• Workup for reversible systemic causes of cognitive deficits
• • B-12 level
  • Rapid plasma reagin (RPR) or Venereal Disease Research Laboratory (VDRL) test, which may be falsely negative in patients older than 65 years, to rule out neurosyphilis
  • Thyroid function tests
  • Electrolytes
  • CBC with differential and platelets
  • If appropriate or other evidence of systemic disease - Rheumatologic workup, including antinuclear antibody (ANA), erythrocyte sedimentation rate (ESR), liver function tests, and ammonia level
  • Manual smear for acanthocytes or genetic testing for Huntington disease if patient has chorea

Imaging Studies

• MRI of brain
• • This study is particularly helpful in evaluating the size of the midbrain if any disturbance of eye movements is noted and progressive supranuclear palsy is being considered. Midbrain size should be relatively normal in CBGD.
  • Cortical atrophy usually occurs, and this can be more localized to the central sulci/supplementary motor area (SMA) than to the temporal/parietal cortex (the latter pattern is seen in dementia of the Alzheimer type).
  • Abnormal signal in basal ganglia can occur with metal deposition in Wilson disease or Hallervorden-Spatz disease.

• Functional brain imaging is not generally needed, but it can be helpful in some patients to document that cognitive changes are neurological and not psychological in origin. Position emission tomography (PET) and single-photon emission computed tomography (SPECT) reveal asymmetric activity in both cortical (frontal-parietal) and subcortical (basal ganglia) regions.

Other Tests

• Neuropsychological testing or evaluation of limb apraxia by a cognitive neurologist, speech pathologist, or occupational therapist with advanced training and experience with neurodegenerative disorders is recommended. This can be useful to differentiate the more common patients with concomitant parkinsonism and Alzheimer disease, who also can be apraxic but should not have as severe a motor coordination deficit or alien limb sign.
• Electroencephalography (EEG) in cases of polymyoclonus or short history of rapid decline
• Somatosensory evoked potentials: These are not generally a part of the clinical workup. If done as part of the workup of reflex myoclonus, they should not show giant potentials.

Procedures

• In patients with prominent segmental myoclonus (especially if involving the face); eye movement disorder; and history of celiac sprue, chronic diarrhea, or unexplained arthritis, consider further workup to rule out the diagnosis of CNS Whipple disease.
• • Lumbar puncture (LP) may be done to examine cerebrospinal fluid (CSF) for cells and elevated protein; the polymerase chain reaction (PCR) test for the organism Tropheryma whippleii should also be done.
  • Consider jejunal biopsy; it can show changes characteristic of Whipple disease in the gut.
  • If diagnosis is strongly desired (familial pattern) or features are atypical (rapid course), consider brain biopsy.

Histologic Findings

Cortical findings include frontoparietal atrophy and astrogliosis, presence of swollen achromatic neurons (ballooned neurons or pale bodies), neuropil threads, and occasionally neurofibrillary tangles. Argyrophilic tau-immunoreactive inclusion bodies can be found subcortically in the substantia nigra, basal ganglia, and dentato-rubro-thalamic tracts. Although this description sounds different from that of progressive supranuclear palsy, tau-positive inclusions of CBGD may be coiled and thus they can be confused with tau-positive neurofibrillary tangles. Some cases of CBGD are thus difficult to distinguish pathologically from progressive supranuclear palsy.

TREATMENT

Section 6 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• References

Medical Care

• On first evaluation, discontinue anticholinergics or other medications that impair attention and memory. Discontinue any medications that may cause parkinsonism. Start vitamin E if the patient has memory loss. Consider empiric treatment of depression and initiate a trial of levodopa/carbidopa (Sinemet) if rigidity and movement disorder are disabling. Institute a plan for titration of this medication to an appropriate level before declaring the patient to be a "levodopa/carbidopa failure." Consider botulinum toxin injections if the patient has painful limb dystonia. Obtain an EEG if the patient has polymyoclonus or rapid decline. Refer to occupational, physical, and speech therapists, as needed, for gait and safety evaluation, assistive devices, and an exercise program to maintain endurance and strength.
• On second evaluation, treat any systemic conditions identified on serologic testing. Discontinue Sinemet if ineffective, and begin empiric trial of second- or third-line dopaminergic agent or consider treatment with clonazepam for myoclonus. Consider a spinal tap if any symptoms suggestive of CNS Whipple disease are present; discuss this possibility with the patient and family. Refer the patient to a geriatric nurse practitioner, case manager, or other dementia resource persons when available. Share reading material on CBGD and dementia with the patient and family. Coordinate consultation with a behavioral neurologist or movement disorder specialist if the family desires.
• On third evaluation, treat any systemic conditions further identified, perform spinal tap, and consider brain biopsy if the diagnosis is still in doubt or if the family or patient may benefit. Consider further adjustment of dopaminergic therapies depending upon clinical response.

Consultations

• Physical and occupational therapist: Sometimes physical and occupational therapy can be helpful to maintain endurance in patients with impaired gait or to teach patients with visual agnosia different strategies for performing activities of daily living.
• Speech therapist: These professionals can train patients with primary progressive aphasia or buccofacial apraxia to use an assistive communication device, similar to those used by patients with amyotrophic lateral sclerosis and other neuromuscular diseases. This training must be instituted early when patients are still capable of learning procedural/motor skills. If the diagnosis is in doubt, speech therapists with graduate training also can assess apraxia with quantitative standardized tests.
• A geriatric case manager, nurse clinician, or social worker can be very helpful in counseling patients and their families on issues relating to increasing disability and, ultimately, end-of-life care.
• Many patients may wish to visit, if only once, a specialist in the area of behavioral neurology or movement disorders to confirm the diagnosis. Some patients find taking part in research studies extremely gratifying as this disorder remains untreatable.

Diet

• Dysphagia may occur in some patients with prominent buccofacial apraxia.
• Speech therapy consultation for swallowing evaluation is recommended.
• Thickened liquids or soft foods (depending upon degree of impairment) may be necessary.

Activity

Activity is not restricted, but motor assistance is required as the disease progresses.

MEDICATION

Section 7 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• References

Unfortunately, no regimen is reported to be highly effective in slowing or reversing motor or cognitive symptoms of this disease. Medications for Parkinson disease, including anticholinergics, levodopa, and dopamine agonists, can reduce the rigidity to a minor extent in some patients and usually are tried at some point in the course of the disease.

Drug Category: Dopaminergic medications

These agents are dopamine receptor agonists.

Drug Name	Levodopa/carbidopa (Sinemet)
Description	Unresponsiveness to this medication supports diagnosis of CBGD; thus, an empiric trial, titrated to high dose (many advocate minimum 4 g daily), is recommended in every patient.
Adult Dose	10/100 PO tid, increase over 2 wk to 25/250 PO tid, then increase by 25/250 q3-4d or weekly until change in motor symptoms or dose of 4 tab 25/250 tid is reached without any response
Pediatric Dose	Not established
Contraindications	Documented hypersensitivity, narrow-angle glaucoma, malignant melanoma, undiagnosed skin lesions
Interactions	Hydantoins, pyridoxine, phenothiazine, and hypotensive agents may decrease effects; antacids and MAOIs increase toxicity
Pregnancy	C - Safety for use during pregnancy has not been established.
Precautions	Nausea and GI complaints common; can be lessened by taking with food but avoid taking with protein; cannot discontinue abruptly; certain adverse CNS effects (eg, dyskinesias) may occur at lower dosages and earlier in therapy with SR form; caution in history of myocardial infarction, arrhythmias, asthma, or peptic ulcer disease; sudden discontinuation of levodopa may cause worsening of Parkinson disease; high-protein diets should be distributed throughout day to avoid fluctuations in levodopa absorption

Drug Name	Bromocriptine (Parlodel)
Description	Semisynthetic ergot alkaloid derivative; strong dopamine D2-receptor agonist; partial dopamine D1-receptor agonist. Stimulates dopamine receptors in corpus striatum. Approximately 28% absorbed from GI tract and metabolized in liver. Approximate elimination half-life is 50 h with 85% excreted in feces and 3-6% eliminated in urine. Initiate at low dosage; slowly increase dosage to individualize therapy. Maintain levodopa dosage during introductory period. Assess dosage titration every 2 wk. Gradually reduce dose in 2.5-mg decrements if severe adverse reactions occur.
Adult Dose	2.5 mg PO bid initially, increase to 15-20 mg bid; usually not helpful
Pediatric Dose	Not established
Contraindications	Documented hypersensitivity, ischemic heart disease, peripheral vascular disorders
Interactions	Ergot alkaloids may increase toxicity; amitriptyline, butyrophenones, imipramine, methyldopa, phenothiazines, reserpine may decrease effects
Pregnancy	C - Safety for use during pregnancy has not been established.
Precautions	Caution in renal or hepatic disease

Drug Name	Ropinirole (Requip)
Description	Often not helpful but a trial probably worthwhile for patients with disabling rigidity.
Adult Dose	0.25 mg PO tid, gradually increase over 1 wk to 1 mg PO tid
Pediatric Dose	Not established
Contraindications	Documented hypersensitivity
Interactions	Estrogens may reduce clearance by 36%; dose adjustment may be required if estrogen therapy stopped or started during treatment with ropinirole Potential exists for substrates or inhibitors of CYP1A2 to alter clearance; if therapy with potent CYP1A2 inhibitor stopped or started during treatment, dose adjustments may be necessary Dopamine antagonists such as phenothiazines, butyrophenones, thioxanthenes, and metoclopramide may diminish effectiveness
Pregnancy	C - Safety for use during pregnancy has not been established.
Precautions	Monitor for signs and symptoms of orthostatic hypotension; dopamine receptor agonists may potentiate dopaminergic adverse effects of levodopa and may cause or exacerbate preexisting dyskinesia (decreasing dose of levodopa may ameliorate this adverse effect); retroperitoneal fibrosis, pulmonary infiltrates, pleural effusion, or pleural thickening have occurred in some patients treated with ergot-derived dopaminergic agents; complete resolution of these complications does not always occur when drug discontinued; because CNS depressants may cause possible additive sedative effects, use caution; cases of rhabdomyolysis have been reported in patients with advanced Parkinson disease treated with pramipexole

Drug Name	Pramipexole (Mirapex)
Description	Nonergot dopamine agonist with specificity to D2 dopamine receptor but has also been shown to bind to D3 and D4 receptors and may stimulate dopamine activity on nerves of striatum and substantia nigra. Often not very helpful, but trial worthwhile.
Adult Dose	0.125 mg PO tid, gradually increase over wk to 1 mg PO tid
Pediatric Dose	Not established
Contraindications	Documented hypersensitivity, orthostatic hypotension (can exacerbate)
Interactions	Cimetidine may increase toxicity; may increase levodopa levels
Pregnancy	C - Safety for use during pregnancy has not been established.
Precautions	Caution in renal insufficiency and preexisting dyskinesias

Drug Name	Amantadine (Symmetrel)
Description	Unknown mechanism of action; may release dopamine from dopaminergic terminals.
Adult Dose	100 mg PO bid
Pediatric Dose	Not established
Contraindications	Documented hypersensitivity
Interactions	Drugs with anticholinergic or CNS stimulant activity increase toxicity; hydrochlorothiazide plus triamterene may increase plasma concentrations
Pregnancy	C - Safety for use during pregnancy has not been established.
Precautions	Caution in liver disease, uncontrolled psychosis, eczematoid dermatitis, seizures, concomitant CNS stimulant drugs; reduce dose in renal disease when treating Parkinson disease; do not discontinue this medication abruptly

Drug Category: Neuroprotective agents

No studies demonstrate that therapy with neuroprotective drugs slows the course of CBGD. However, such therapy does affect the course of other neurodegenerative dementias; therefore, neuroprotective agents generally are offered empirically.

Drug Category: Nonsteroidal anti-inflammatory agents (NSAIDS)

Have analgesic, anti-inflammatory, and antipyretic activities. Their mechanism of action is not known, but they may inhibit cyclooxygenase activity and prostaglandin synthesis. Other mechanisms may exist as well, such as inhibition of leukotriene synthesis, lysosomal enzyme release, lipoxygenase activity, neutrophil aggregation, and various cell-membrane functions.

Drug Category: Benzodiazepines

By binding to specific receptor sites, these agents appear to potentiate the effects of GABA and facilitate inhibitory GABA neurotransmission and other inhibitory transmitters.

Drug Category: Toxins

Botulinum toxin can inhibit transmission of impulses in neuromuscular tissue.

FOLLOW-UP

Section 8 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• References

Further Inpatient Care

• Inpatient admission can facilitate a more rapid diagnostic workup; if deterioration has been rapid with a high degree of suspicion, a brain biopsy may be advisable. This is completed over 2 days with initial contact made by a case manager. Referral for brain biopsy then can be expedited and the procedure carried out on the same admission.

Further Outpatient Care

• Periodic follow-up is appropriate to adjust dopaminergic medications or treatment for depression or other conditions. It may also help the caregiver to make plans for future care when the patient becomes more disabled.

Complications

• Patients with cerebral atrophy can develop subdural hematoma after a spinal tap. Some physicians admit for 23-hour observation when performing LP to observe for headache, sleepiness, or other changes in mental status.

Prognosis

• Unfortunately, this disorder is progressive, leading to increased cognitive and motor disability.
• Aspiration pneumonia or other complications are usually the cause of death after the patient has lost the ability to care for him/herself and has lost mobility.

Patient Education

• A geriatric case manager can be very helpful in counseling the patient and family about the prognosis, community resources, need for supervision, etc.
• Massachusetts General Hospital (ie, Harvard neurology program) provides links to an online forum and chat rooms for patients and their families. Some may find them helpful sources of information and support.
• For quality care, screen patients with movement disorders for fall risk by inquiring whether patients have had 2 or more falls over the past year or one or more falls with injury. Such patients would be eligible for physical therapy assessment and aggressive fall prevention via environmental management and caregiver/patient education.

MISCELLANEOUS

Section 9 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• References

Special Concerns

• While the patient is able to participate meaningfully, legal issues such as durable power of attorney, living will, and wishes regarding disposition can and should be addressed sensitively.

REFERENCES

Section 10 of 10

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• References

• Benito-León J, Alvarez-Linera J, Louis ED. Neurosyphilis masquerading as corticobasal degeneration. Mov Disord. Nov 2004;19(11):1367-70. [Medline].
• Bergeron C, Pollanen MS, Weyer L. Unusual clinical presentations of cortical-basal ganglionic degeneration. Ann Neurol. Dec 1996;40(6):893-900. [Medline].
• Boeve BF, Maraganore DM, Parisi JE et al. Pathologic heterogeneity in clinically diagnosed corticobasal degeneration. Neurology. Sep 11 1999;53(4):795-800. [Medline].
• Clark AW, Manz HJ, White CL 3d. Cortical degeneration with swollen chromatolytic neurons: its relationship to Pick's disease. J Neuropathol Exp Neurol. May 1986;45(3):268-84. [Medline].
• Eidelberg D, Moeller JR, Sidtis JJ. Corticodentatonigral degeneration: metabolic asymmetries studied with 14-F-fluorodeoxyglucose and positron emission tomorgraphy. Neurology (Cleveland). 1989;39 (Suppl 1):164.
• Fahn S, Przedborski S. Parkinsonism. In: Rowland LP, ed. Merritt's Textbook of Neurology. 11^th ed. Baltimore: Williams & Wilkins; 2005:720.
• Feany MB, Mattiace LA, Dickson DW. Neuropathologic overlap of progressive supranuclear palsy, Pick's disease and corticobasal degeneration. J Neuropathol Exp Neurol. Jan 1996;55(1):53-67. [Medline].
• Fukui T, Sugita K, Kawamura M. Primary progressive apraxia in Pick's disease: a clinicopathologic study. Neurology. Aug 1996;47(2):467-73. [Medline].
• Gibb WR, Luthert PJ, Marsden CD. Corticobasal degeneration. Brain. Oct 1989;112 ( Pt 5):1171-92. [Medline].
• Heilman KM. The apraxia of CBGD. Mov Disord. 1996;11:348.
• Heilman KM, Rothi LJG. Apraxia. In: Heilman KM, Valenstein E, eds. Clinical Neuropsychology. 2^nd ed. New York: Oxford University Press; 1985:131-50.
• Jendroska K, Rossor MN, Mathias CJ. Morphological overlap between corticobasal degeneration and Pick's disease: a clinicopathological report. Mov Disord. Jan 1995;10(1):111-4. [Medline].
• Kertesz A. Frontotemporal dementia, Pick disease, and corticobasal degeneration. One entity or 3? 1. Arch Neurol. Nov 1997;54(11):1427-9. [Medline].
• Kertesz A, Hudson L, Mackenzie IR. The pathology and nosology of primary progressive aphasia. Neurology. Nov 1994;44(11):2065-72. [Medline].
• Kertesz A, McMonagle P, Blair M, Davidson W, Munoz DG. The evolution and pathology of frontotemporal dementia. Brain. Sep 2005;128(Pt 9):1996-2005. [Medline].
• Kertesz A, Munox DG. Pick's Disease and Pick complex. New York: Wiley-Liss; 1998.
• Kompoliti K, Goetz CG, Boeve BF. Clinical presentation and pharmacological therapy in corticobasal degeneration. Arch Neurol. Jul 1998;55(7):957-61. [Medline].
• Lang AE. Cortical basal ganglionic degeneration presenting with "progressive loss of speech output and orofacial dyspraxia" [letter; comment]. J Neurol Neurosurg Psychiatry. Nov 1992;55(11):1101. [Medline].
• Lang AE, Riley DE, Bergeron C. Cortical-basal ganglionic degeneration. In: Calne DB, ed. Neurodegenerative Diseases. Philadelphia: WB Saunders; 1994:877-94.
• Leiguarda R, Lees AJ, Merello M. The nature of apraxia in corticobasal degeneration. J Neurol Neurosurg Psychiatry. Apr 1994;57(4):455-9. [Medline].
• Markus HS, Lees AJ, Lennox G. Patterns of regional cerebral blood flow in corticobasal degeneration studied using HMPAO SPECT; comparison with Parkinson's disease and normal controls. Mov Disord. Mar 1995;10(2):179-87. [Medline].
• McMonagle P, Blair M, Kertesz A. Corticobasal degeneration and progressive aphasia. Neurology. Oct 24 2006;67(8):1444-51. [Medline].
• Paulus W, Selim M. Corticonigral degeneration with neuronal achromasia and basal neurofibrillary tangles. Acta Neuropathol (Berl). 1990;81(1):89-94. [Medline].
• Rebeiz JJ, Kolodny EH, Richardson EP Jr. Corticodentatonigral degeneration with neuronal achromasia. Arch Neurol. Jan 1968;18(1):20-33. [Medline].
• Riley DE, Lang AE, Lewis A. Cortical-basal ganglionic degeneration. Neurology. Aug 1990;40(8):1203-12. [Medline].
• Sakurai Y, Hashida H, Uesugi H. A clinical profile of corticobasal degeneration presenting as primary progressive aphasia. Eur Neurol. 1996;36(3):134-7. [Medline].
• Sano M, Ernesto C, Thomas RG. A controlled trial of selegiline, alpha-tocopherol, or both as treatment for Alzheimer's disease. The Alzheimer's Disease Cooperative Study. N Engl J Med. Apr 24 1997;336(17):1216-22. [Medline].
• Sawle GV, Brooks DJ, Marsden CD, Frackowiak RS. Corticobasal degeneration. A unique pattern of regional cortical oxygen hypometabolism and striatal fluorodopa uptake demonstrated by positron emission tomography. Brain. Feb 1991;114 ( Pt 1B):541-56. [Medline].
• Schofield EC, Caine D, Kril JJ, Cordato NJ, Halliday GM. Staging disease severity in movement disorder tauopathies: brain atrophy separates progressive supranuclear palsy from corticobasal degeneration. Mov Disord. Jan 2005;20(1):34-9. [Medline].
• Watts RL, Williams RS, Growden JD. Corticobasal ganglionic degeneration. Neurology (Cleveland). 1985;35 (Suppl 1):178.

Article Last Updated: Jul 9, 2007