12.4.09 laudate spinal lesions
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Acute Myelopathies
Darrell Laudate
12/4/09 AM Report
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Overview of Acute Myelopathy
Spinal cord dysfunction or myelopathy, can occurdue to a lesion arising within the spinal cord or due
to compression of the spinal cord originating outsideof it
Frequently devastating, often producing
quadriplegia, paraplegia, and sensory deficits
Many spinal cord diseases are reversible ifrecognized and treated at an early stage
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Transverse Myelopathy vs. Myelitis
Transverse Myelopathy refers to clinicalpresentation of severe motor, sensory, and
autonomic dysfunction (bowel, bladder, andsexual abnormalities ) below a spinal cord lesiondue to any acute/ subacute process affecting thespinal cord, compressive or not
Often associated with back pain
Transverse Myelitis refers to an inflammatoryprocess of the grey and white matter of the spinalcord
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Transverse Myelopathies (cont.)
Localization of the lesion depends upon the level of the spinal cord involvedand the extent of the involvement of the various long tracts. In some cases,there is almost total paralysis and sensory loss below the level of the lesion,
others only partial loss
If cervical area is involved, all four limbs may be involved and there is riskof respiratory paralysis (segments C3,4,5 to diaphragm) Lhermitte's sign: an electric shock-like sensation down the neck,
back, or extremities that occurs with bending of the neck Lesions of the lower cervical (C2-T1) region will cause a combination of
upper and lower motor neuron signs in the upper limbs, and exclusivelyupper motor neuron signs in the lower limbs.
A lesion of the thoracic spinal cord (T1-12) will produce a spasticparaplegia.
A lesion of the lower part of the spinal cord (L1-S5) often produces acombination of upper and lower motor neuron signs in the lower limbs
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Upper vs Lower Motor Neuron Lesions
Lower motor neuron lesionis a lesion which affects nerve fibers traveling from theanterior horn of the spinal cord to the relevant muscle(s) Associated with areflexia
leads to flaccid paralysis (paralysis accompanied by muscle loss)
Upper motor neuron lesionis a lesion of the neural pathway above the anterior horncell or motor nuclei of the cranial nerves and are marked by:
Spasticity, increase in tone in the extensor muscles (lower limbs) or flexor muscles(upper limbs)
Clasp-knife response where initial resistance to movement is followed by relaxation Weakness in the flexors (lower limbs) or extensors (upper limbs), but no muscle
wasting Brisk tendon jerk reflexes Babinski or Hoffman sign is present increase deep tendon reflex Pronator drift
(Spinal Shock - loss of sensationaccompanied by motor paralysiswith initial loss butgradual recovery of reflexes Occurs following a spinal cord injury, thus what may have looked like a lower motor
neuron lesion can later reveal itself to be an upper motor lesion)
http://en.wiktionary.org/wiki/sensationhttp://en.wikipedia.org/wiki/Paralysishttp://en.wikipedia.org/wiki/Reflexeshttp://en.wikipedia.org/wiki/Reflexeshttp://en.wikipedia.org/wiki/Paralysishttp://en.wiktionary.org/wiki/sensation -
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Important Dermatomal Landmarks
C2- posterior half of the skull cap C3- area correlating to a high turtle neck shirt C4- area correlating to a low-collar shirt C6- (radial nerve) 1st digit (thumb) C7- (median nerve) 2nd and 3rd digit C8- (ulnar nerve) 4th and 5th digit, also the funny bone T4- nipples. T5- Inframammary fold. T6/T7- xiphoid process. T10- umbilicus(important for early appendicitis pain) T12- pubic bonearea. L1- inguinal ligament L4- includes the knee caps
http://en.wikipedia.org/wiki/C2_nervehttp://en.wikipedia.org/wiki/C3_nervehttp://en.wikipedia.org/wiki/C4_nervehttp://en.wikipedia.org/wiki/C6_nervehttp://en.wikipedia.org/wiki/Radial_nervehttp://en.wikipedia.org/wiki/Thumbhttp://en.wikipedia.org/wiki/C7_nervehttp://en.wikipedia.org/wiki/C8_nervehttp://en.wikipedia.org/wiki/Ulnar_nerve#Cutaneoushttp://en.wikipedia.org/wiki/Funny_bonehttp://en.wikipedia.org/wiki/T4_nervehttp://en.wikipedia.org/wiki/Nipplehttp://en.wikipedia.org/wiki/T5_nervehttp://en.wikipedia.org/wiki/Inframammary_foldhttp://en.wikipedia.org/wiki/T6_nervehttp://en.wikipedia.org/wiki/T7_nervehttp://en.wikipedia.org/wiki/Xiphoid_processhttp://en.wikipedia.org/wiki/T10_nervehttp://en.wikipedia.org/wiki/Umbilicushttp://en.wikipedia.org/wiki/T12_nervehttp://en.wikipedia.org/wiki/Pubic_bonehttp://en.wikipedia.org/wiki/L1_nervehttp://en.wikipedia.org/wiki/L4_nervehttp://en.wikipedia.org/wiki/L4_nervehttp://en.wikipedia.org/wiki/L1_nervehttp://en.wikipedia.org/wiki/Pubic_bonehttp://en.wikipedia.org/wiki/T12_nervehttp://en.wikipedia.org/wiki/Umbilicushttp://en.wikipedia.org/wiki/T10_nervehttp://en.wikipedia.org/wiki/Xiphoid_processhttp://en.wikipedia.org/wiki/T7_nervehttp://en.wikipedia.org/wiki/T6_nervehttp://en.wikipedia.org/wiki/Inframammary_foldhttp://en.wikipedia.org/wiki/T5_nervehttp://en.wikipedia.org/wiki/Nipplehttp://en.wikipedia.org/wiki/T4_nervehttp://en.wikipedia.org/wiki/Funny_bonehttp://en.wikipedia.org/wiki/Ulnar_nerve#Cutaneoushttp://en.wikipedia.org/wiki/C8_nervehttp://en.wikipedia.org/wiki/C7_nervehttp://en.wikipedia.org/wiki/Thumbhttp://en.wikipedia.org/wiki/Radial_nervehttp://en.wikipedia.org/wiki/C6_nervehttp://en.wikipedia.org/wiki/C4_nervehttp://en.wikipedia.org/wiki/C3_nervehttp://en.wikipedia.org/wiki/C2_nerve -
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Evaluation of suspected myelopathy
Imaging is indicated in all patient with suspicion for myelopathy MRI is generally the most appropriate study as it images the spine,
paraspinal region, and spinal cord; also may reveal evidence of intrinsic
lesions most patients with suspected cord compression should have total spinal
cord imaging sole imaging of the lumber spine is often ordered with cord compression
suspicion, but recall the spinal cord ends at L1, thus visualization of thespinal cord is not possible with a lumbar MRI alone
lumbar MRI is useful however to exclude cauda equina
compression (lower extremity weakness and sensory andbladder disturbances without upper motor neuron signs)
Exceptions may include pts with upper and lower extremity symptoms ascervical localization is likely -> Cervical MRI
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Other Studies
Lumbar Puncture
Serologic Studies as clinically indicated CT myelogram may be beneficial in
patients with suspected inflammatoryor demyelinative lesions of the spinalcord
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Noncompressive Myelopathies
Vascular
Arteriovenous malformation
Antiphospholipid syndrome and other hypercoagulable states
Inflammatory Multiple sclerosis
Neuromyelitis optica (Devics Disease)
Transverse myelitis (idiopathic)
Sarcoidosis
Vasculitis
Infectious/Postinfectious Viral: VZV, HSV-1 & -2, CMV, HIV, HTLV-I, enteroviruses,
flaivaviruses
Bacterial and mycobacterial: Borrelia, Listeria, syphilis, Mycoplasmapneumoniae
Parasitic: schistosomiasis, toxoplasmosis
Metabolic
Vitamin B12 deficiency (subacute combined degeneration) Copper deficiency
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Compressive Myelopathies
Cervical spondylosis
Epidural, intradural, or intramedullary neoplasm
Epidural abscess
Epidural hemorrhage/hematoma
Herniated disc
Posttraumatic compression by fractured or displaced vertebra orhemorrhage
Clinical criteria alone cannot distinguish spinal cordcompression and intrinsic cord lesions
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Acute Viral Myelitis Two Forms
Enteroviruses (poliovirus, coxsackie virus, and enterovirus 71), Flaviviruses(West Nile virus and Japanese encephalitis virus) have been known to targetthe gray matter (Anterior horn cells) of the spinal cord, producing acute lowermotor neuron disease.1
usually accompanied with fever, headache, and meningismus produces asymmetrical flaccid weakness with reduced or absent reflexes
and few sensory symptoms or signs MRI often shows hyperintensities in the anterior horns of the spinal cord
on T2-weighted imaging Cerebrospinal fluid (CSF) analysisdemonstrates a moderate pleocytosis
These features help to distinguish this form of viral myelitis from Guillain-Barr syndrome, which usually produces symmetric deficits, with no MRIabnormalities, and is associated with elevated CSF protein levels withoutpleocytosis.
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Acute Viral Myelitis
CMV, VZV, HSV I &II, HCV, and EBV are associated with asecond form of viral myelitis has clinical and diagnostic testfeatures that are similar to transverse myelitis
Association between the myelitis and the virus is not alwaysclear, some may represent post-infectious transverse myelitis,others, a positive polymerase chain reaction (PCR) test in theCSF suggests that the myelitis is directly related to the viralinfection
Treated with Herpes zoster, HSV, and EBV myelitis are treatedwith intravenous acyclovir (10 mg/kg q8h) or oral valacyclovir(2 gm tid) for 1014 days; CMV with ganciclovir (5 mg/kg IVbid) plus foscarnet (60 mg/kg IV tid), or cidofovir (5 mg/kg perweek for 2 weeks).2
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Other Infectious Myelopathies
HIV
More of a chronic myelopathy, Often found mostly in late stages of AIDS andassociated with AIDS related dementia in half
slowly progressive spastic paraparesis is accompanied by loss of vibration andposition sense and urinary frequency, urgency, and incontinence
CSF may show nonspecific protein elevation
ART may reverse the symptoms3
Bacterial
Mycoplasma (acute and post infectious), Listeria monocytogenes TB
via secondary cord compression from verterbral osteomyelitis, aka Potts disease Also via compressive tuberculomas
Lyme disease Cases have been described in which clinical and MRI features resembling
acute transverse myelitis have been attributed to Lyme disease.4
CSF in these cases typically demonstrates a lymphocytic pleocytosis and elevated
protein
Schistosomiasis (in endemic areas)
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Tabes Dorsalis (Locomotor Ataxia)
Form of tertiary neurosyphilis in which the nerves of the dorsal (or posterior)columns degenerate
Loss of sense of position (proprioception), vibration, and discriminativetouch
Latency period of 3-20 years
Cardinal signs of tabes are loss of reflexes in the legs; impaired position andvibratory sense; Romberg's sign also:
bilateral Argyll Robertson pupils
fleeting and repetitive lancinating pains, primarily in the legs Paresthesias/ formincation visceral crisis (Bladder disturbances, and acute abdominal pain with vomiting personality changes, dementia, deafness, visual skeletal musculature is hypotonic due to destruction of the sensory limb of the
spindle reflex Ataxia of the legs and (tabetic) gait due to loss of position sense occurs in half
of patients
http://en.wikipedia.org/wiki/Proprioceptionhttp://en.wikipedia.org/wiki/Proprioception -
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Tabes dorsalis (cont.)
VDRL & RPR (nontreponemal tests) may be nonreactive in late neurosyphilis
If suspcion suspicion for neurosyphilis, serum FTA-ABS or TPPA (treponemaltests) are preferred
CSF may be completely normal in tabes dorsalis, or may show mildlymphocytic pleocytosis with 10 to 50 cells/microL and protein concentrationsof 45 to 75 mg/dL.
Syphilitic meningovascular myelitis can represent an earlier form of syphilisinfection
focal inflammation of the meninges can secondarily affect the adjacentanterior spinal artery thus result in a CVA or spinal cord infarction
Treatment - Penicillin G 3 to 4 million units IV every four hours or 24 millionunits continuous IV infusion for 10 to 14 days
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Connective tissue Associated
Myelopathies SLE
May be the initial feature but onset is usually present with other active lupus signs.
thought to be due to an arteritis, with resultant ischemic necrosis of the spinal cord
ANA, ds-DNA, anti-Sm, Anti-neuronal (may correlate with active CNS lupus) Has been associated with antiphospholipid antibodies in some studies but not all.5
Treatment: Prednisone (1.5 mg/kg per day), plasmapheresis, and cyclophosphamide.6
Antiphospholipid antibodies a may also benefit with warfarin as well as steroids andimmunosuppressive treatment.7
Mixed connective tissue disease
Sjogren's syndrome (antibodies to the Ro/SSA or La/SSB)
Scleroderma (ANA, anti-Scl-70, anti-centromere (ACA), anti-RNA polymerase III, and anti-beta2-glycoprotein I antibodies)
Ankylosing spondylitis
Acute myelopathy will typically occur in the setting of fracture of ankylosed spine or atlantoaxial-axial subluxation
cauda equina sydrome rare but associated with long standing disease
Rheumatoid arthritis
atlantoaxial subluxation, atlantoaxial impaction, and/or subaxial subluxation Rarely associated with CNS vasculitis and more rarely with myelopathy from vasculitis
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Sarcoid Neurosarcoidosis
Typically occur perivascularly, but they can be extramedullary orintramedullary, and can involve the cauda equina.
Occurs 5% of Sarcoid patients
MRI signal abnormalities are not specific
neurosarcoid lesions can appear similar to transverse myelitis orcan resemble a tumor
CSF profile consists of variable lymphocytic pleocytosis; oligoclonalbands are present in one-third of case
Generally treated with corticosteroids and other immunomodulatoryagents and can improve
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B12 Deficiency (subacute combined
degeneration of spinal cord)
Damage to peripheral nerves caused by demyelinationand irreversiblenerve cell death.
Symptoms include paresthesias in the hands and feet loss of vibration and position sensation progressive spastic and ataxic weakness Loss of reflexes due to an associated peripheral neuropathy in a
patient who also has Babinski signs, is an important diagnostic
clue Optic atrophy and irritability or other mental changes may be
prominent in advanced cases
This myelopathy tends to be diffuse rather than focal; signs aregenerally symmetric and reflect predominant involvement of the
posterior and lateral tracts, including Romberg's sign
http://en.wikipedia.org/wiki/Demyelinationhttp://en.wikipedia.org/wiki/Demyelination -
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B12 deficiency (cont.)
Usually established by the presence of decreased Vit B12
level
in the cases of low-normal B12, the presence of elevated MMAand homocysteine levels may be useful
Treatment: 1mg Cbl IM once daily for 1 week, followed by
1 mg IM every week for four weeks
if the underlying disorder persists, 1 mg every month
for the remainder of the patient's life.
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Hypocuric Myelopathy (Copper
Deficiency)
Very similar to subacute combined degeneration Progressive spasticity, severe gait abnormalities including ataxia,
and a neuropathy. Also associated with anemia and neutropenia in certain patients
More common after gastric bypass, also with zinc supplementation
Diagnosis usually confirmed with low levels of serum copper are foundand often there is also a low level of serum ceruloplasmin
Symptoms are potentially reversible with copper supplementation andreversal of underlying cause
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Multiple Sclerosis
Most common autoimmune inflammatory demyelinating diseaseof the CNS
Women of Northern European descent who are of child-bearingage.
Histological examination of active plaques reveals perivascularinfiltration of lymphocytes (predominantly T cells) andmacrophages with occasional plasma cells. Perivascular andinterstitial edema may be prominent.
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Multiple Sclerosis (cont.)
Multiple sclerosis (MS) is a clinical diagnosis. There are no clinicalfindings that are unique to this disorder, but some are highlycharacteristic
Older criteria considered clinical characteristics and a number oflaboratory studies
these findings were then used to place patients in categoriesranging from clinically definite to laboratory supported definite toclinically probable to laboratory supported probable MS
McDonald criteria focus on a demonstration with clinical, laboratoryand radiologic data of the dissemination of MS lesions in time andspace, also incorporated specific MRI findings into the diagnosticscheme
A diagnosis cannot be made until other possible conditions have beenruled out and there is evidence of demyelinating events separated
anatomically and in time
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Multiple Sclerosis (cont.) CSF
oligoclonal bands using isoelectric focusing is the most important diagnostic CSFstudy when determining a diagnosis of MS
2/3 will have normal leukocyte count >50cells/microliter occurs only rarely and should raise suspicion of alternative
etiology
Will also see elevation of the CSF immunoglobulin level relative to other proteincomponents, suggesting intrathecal synthesis, generally IgG
MRI Cerebral or spinal plaques that are ovoid and hyperintense on proton density and T2-weighted
studies, and they are hypointense (if visible at all) on T1-weighted images. Conventional T2-weighted MRI techniques may underestimate MS plaque size
and burden, Diffusion tensor imaging and MR spectroscopy may correct this
Evoked potentials(EPs): CNS electrical events generated by peripheral stimulation ofa sensory organ)
Can detect abnormal CNS function that may be clinically undetectable or helpdefine the anatomical site of the lesion in tracts not easily visualized by imaging(e.g., optic nerves, dorsal columns).
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Neuromyelitis optica (Devics Disease)
Autoimmune, inflammatory disorder in which the optic nerves and spinal cord aretargeted but may also affect the brain,
Resembles multiple sclerosis (MS) as it has varying degrees of weakness or paralysis in
the legs or arms, loss of sensation (including blindness), and/or bladder and boweldysfunction.
Lesions are different from those observed in MS in that the attacks appear to be notmediated by the immune system's T cells but rather by antibodies called NMO-IgG thattarget aquaporin 4 of astrocytes.6
Acts as a channel for the transport of water across the cell membrane Found in the processes of the astrocytes that surround the blood-brain barrier,
This blood-brain barrier is weakened in Devic's disease, but it is unclear howNMO-IgG immune response leads to demyelination
Criteria: Optic neuritis, Myelitis, and one of the following:
MRI evidence of a contiguous spinal cord lesion three or more segments in length,or
Seropositivity for NMO-IgG
Treatment: Steroids, Cytoxan, PLEX, +/- Rituximab
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Cervical Spondylosis
Chronic degenerative and hypertraphic changes that involveintervertebral disks, vertebral bodies, facet joints, and ligaments if severe, can result in narrowing of cervical spinal canal and
cause spinal cord compression In many case series, cervical spondylotic myelopathy is the most
common cause of myelopathy, particularly in older adults
Cervical Spondylotic Myelopathy clinical syndrome associated with spondylosis but with spinal cord
dysfunction commonly in pts > 55y, perhaps most common form of myelopathy insidious onset of numbness, parathesias in upper extremities,
spastic or stiff-legged gait that is often not associated with pain surgical decompression is generally used to treat if symptomatic,
although there is no evidence from RCT proving the efficacy of this
therapy7
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Metastatic Disease to Spinal Cord
Oncologic emergency
usually requring treatment with corticosteroids (usually
dexamethasone), and emergent radiation therapy or surgery
indications for decompressive surgery for metastatic epiduralspinal cord compression includes: when tissue diagnosis isneeded, presence of spinal instability, or tumor is known to beradioresistant
One study showed patients who underwent anteriordecompressive surgical resection of metastatic epidural spinalcord compression due to cancer had better ambulatoryoutcomes than with radiation therapy alone.8
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Epidural Abscess
Rare, occurring in only 1 patient per 10,000 admitted to the hospital.9
Most common pathogen is Staphylococcus aureus, which accounts forabout two-thirds of cases 9
Typically originate via contiguous spread from infections of skin andsoft tissues or as a complication of spinal surgery and other invasiveprocedures, including indwelling epidural catheters.
Expected back and/or radicular pain usually but not alwaysaccompanied systemic signs of infection
MRI preferred test Requires emergent surgical decompression and antibiotic therapy are
indicated to treat epidural abscess
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Spinal Cord Infarction
Rare compared with CVA
Most frequently caused by surgical procedures and pathologiesaffecting the aorta
May also occur in the setting of vascular risk factors or aorticdisease
Presents with sudden spinal cord dysfunction that typicallycorresponds to the territory of the anterior spinal artery
Weakness and pinprick loss below the level of the infarction butsparing vibration and position sense
No treatment available and prognosis is variable and dependent uponseverity of presenting deficit
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Dural AVM of Spinal Cord
Rare cause of ischemic spinal cord dysfunction Obstructs venous outflow of the spinal cord
May progress over months to years
Surgical obliteration of the fistula can potentiallyreverse this condition
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1) Solomon et al. Infectious causes of acute flaccid paralysis. Curr Opin Infect Dis. 2003 Oct;16(5):375-81
2) Hauser et al. "Chapter 372. Diseases of the Spinal Cord" (Chapter): Harrison's Principles of Internal Medicine, 17e:http://www.accessmedicine.com/content.aspx?aID=2904373.
3) Meurs et al. Acute transverse myelitis as a main manifestation of early stage II neuroborreliosis in two patients. Eur Neurol 2004;52:186.
4) Staudinger et al. Remission of HIV myelopathy after highly active antiretroviral therapy. Neurology 2000; 54:267.
5) Lennon et al. IgG marker of optic-spinal multiple sclerosis binds to the aquaporin-4 water channel. J. Exp. Med.2005. 202 (4): 4737.
6) Transverse myelitis as the first manifestation of systemic lupus erythematosus or lupus-like disease: good functional outcome andrelevance of antiphospholipid antibodies. AU D'Cruz DP; Mellor-Pita S; Joven B; Sanna G; Allanson J; Taylor J; Khamashta MA;Hughes GR SO J Rheumatol 2004 Feb;31(2):280-5.
7) Transverse myelopathy in systemic lupus erythematosus: an analysis of 14 cases and review of the literature. AU Kovacs B; LaffertyTL; Brent LH; DeHoratius RJ SO Ann Rheum Dis 2000 Feb;59(2):120-4.
8) Acute transverse myelopathy in systemic lupus erythematosus: clinical presentation, treatment, and outcome. AU Mok CC; Lau CS;Chan EY; Wong RW SO J Rheumatol 1998 Mar;25(3):467-73
9) Porter et al. Endocrine and reproductive manifestations of sarcoidosis. QJM 2003; 96:553.
10) McCormick et al. Cervical Spndylotic myelopathy: make the difficult diagnosis, then refer to surgery. Cleve Clin J Med. 2003;70:899-904
11) Patchell et al. Direct decompressive surgical resection in the treatment of spinal cord compression caused by metastatic cancer: arandomised trial. Lancet. 2005;366:643.
12) Darouiche, RO. Spinal epidural abscess. N Engl J Med 2006; 355:2012.
References