​Weakness of both lower limbs + decreased vision, detailed diagnosis ideas have been summarized

*Only for medical professionals to read and refer to the Neurological Archives: Layers of analysis, improve clinical diagnosis and treatment thinking.
Weakness of the lower limbs is a common clinical symptom, and the cause is more complicated.
It can be central nervous system disease or located in the peripheral nervous system
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Decreased vision is more common in the optic nerve itself and also in the eyeball.
So, when the weakness of the lower limbs and the decreased vision appear at the same time, how should we locate and qualitatively diagnose it? Case Let's look at a case first
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The patient Wang Moumou, female, 32 years old
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Main complaint: weakness of both lower limbs for 4 months, loss of vision in the left eye for 2 days
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▌ History of present illness: The patient developed weakness in both lower limbs before April, manifested as weakness that gradually worsened, and fell due to weakness in the morning, and the strength of both upper limbs was normal
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Accompanied by sensory disturbances (numbness from the feet to the upper trunk) and frequent paroxysmal pain (radiating pain in the upper and lower limbs when the neck is flexed)
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Two days ago, the patient experienced decreased vision in the left eye, and at the same time, the patient had moderate to severe pain in the left posterior orbit, and the pain increased during eye movement
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Past history: past physical fitness
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Personal history, family history: nothing special
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▌ Physical examination: The vision in the left eye of the patient can only see the number of fingers, and the vision in the right eye is normal
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Eye movements are normal on both sides, but movement can induce pain in the left posterior orbit
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The patient has no diplopia
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The rest of the cranial nerve examination results are normal
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Nervous system examination: increased muscle tone of both lower limbs, normal muscle tone of both upper limbs, level 5 muscle strength of both upper limbs, and level 2 muscle strength of both lower limbs
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Extremities tendon reflex (+++), bilateral Pap sign is positive, and the superficial sensation of both lower limbs is decreased
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The patient also has urinary retention
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▌ Auxiliary examination: hematology examination: there is no obvious abnormality in blood routine, electrolytes, and biochemical indicators
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Anti-nuclear antibody was weakly positive, but anti-double-stranded DNA antibody, anti-SSA antibody, anti-SSB antibody, anti-phospholipid antibody, and anti-Scl-70 antibody were all negative
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Aquaporin antibody (AQP4 antibody: NMO-IgG) is strongly positive
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Cerebrospinal fluid (CSF) test results indicated that the white blood cells increased to 75×106L, and neutrophils accounted for 80%
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CSF protein and sugar content are normal
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The oligoclonal zone of CSF was negative
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Spinal cord MRI: Transverse long-segment signal changes in the cervical and thoracic spinal cord, involving the brainstem
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Figure 1: MRI of the patient's spinal cord and brain MRI (enhanced): the left optic nerve is enhanced, which is consistent with the manifestations of optic neuritis, and there is no T2 hyperintensity lesion in the brain parenchyma
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Figure 2: How to locate and qualitatively diagnose the patient's brain MRI (enhanced)? ▌ Location diagnosis: The patient is weak in both lower limbs with sensory disturbances and paroxysmal pain.
It is located in the spinal cord.
Because motor, sensory and autonomic nerves are all involved, it is considered as a transverse spinal cord injury
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Loss of vision in the left eye, located on the left optic nerve
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▌ Qualitative diagnosis: young female patients, subacute onset, clinical manifestations of spinal cord and optic nerve injury symptoms, imaging findings found lesions in long segments of the spinal cord (> 3 segments), laboratory tests showed positive AQP4 antibody, combined with clinical, imaging and According to the biochemical performance, it is not difficult to diagnose the patient as neuromyelitis optica (NMO) in this case
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But in the face of such cases, we must learn the diagnosis and differential diagnosis of transverse spinal cord injury and optic neuropathy
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Differential diagnosis of transverse spinal cord injury Transverse spinal cord injury: there are various motor, sensory, and sphincter dysfunctions below the damage level.
At the same time, when certain segments of the spinal cord are damaged, they will show the pathological characteristics of these segments, such as diseased segments Muscle flaccid paralysis and atrophy, loss of reflex, radicular pain, or hypoesthesia or loss of radicular distribution will occur in the segment
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These symptoms are called segmental symptoms, which are of great value for the location and diagnosis of lesions
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The determination of the sensory disturbance plane and the change of reflex are also of great help to the segmental positioning of the diseased spinal cord
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1.
NMO-related transverse myelitis can be combined with optic neuritis
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MRI of the spinal cord can show abnormal T2 signals in the long-segment spinal cord, and MRI symmetrical signal changes over the length of at least 3 vertebral body segments
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Brain MRI lesions do not meet the diagnostic criteria for MS (normal or in line with the classic NMO lesion distribution: hypothalamus, corpus callosum, periventricular or brainstem)
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NMO-IgG is serologically positive and oligoclonal bands are negative (about 80% of patients)
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The number of cerebrospinal fluid cells increased significantly (white blood cells>50×106L), mainly neutrophils
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2.
Transverse myelitis associated with multiple sclerosis can cause other neurological diseases (optic neuritis, brainstem syndrome, cortical motor or sensory disorders)
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Spinal cord MRI shows asymmetrical T2 abnormal signals and the length of the lesion rarely exceeds 2 vertebral body segments
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Cerebrospinal fluid has a slight increase in cells (white blood cells <50×106L), mainly neutrophils
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Cerebrospinal fluid (and blood) mismatched oligoclonal bands are positive
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3.
System immune disease-related myelitis may be related to the systemic manifestations of autoimmune diseases, such as skin rash or arthritis, coexist with myelitis and previous symptoms of autoimmune disease
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Serum autoimmune disease test results can be positive
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Other auxiliary examinations support the diagnosis
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4.
Sudden onset of anterior spinal artery occlusion
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It is in line with the anterior spinal artery syndrome (paraplegia of the lower limbs, loss of pain and temperature sensation, relative retention of vibration and proprioception)
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There may be risk factors for vascular disease (hypertension, diabetes, smoking) or risk factors for peripheral vascular embolism
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Spinal cord MRI showed T2 thin line-like abnormal signals, confined to the anterior 2/3 of the spinal cord, accompanied by DWI signal changes
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5.
Spinal arteriovenous malformations or arteriovenous fistulas usually progress gradually and worsen stepwise
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The combined upper and lower motor elements are damaged
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MRI of the spinal cord can show long, patchy abnormal T2 signals, and the lesions are enhanced by gadolinium
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Tortuous blood vessels can be seen on the surface of the spinal cord, and spinal cord angiography can confirm the diagnosis
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6.
History of radiation therapy for radiation myelopathy, the area involves the spinal cord
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Progressively worsening spinal cord lesions with spinal atrophy (rare, but may present subacute manifestations)
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Spinal cord MRI showed spinal cord atrophy with abnormal T2 signal, and in chronic cases, adjacent vertebral body lesions were seen
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7.
B12 or folic acid-deficiency myelopathy may have a history of untreated pernicious anemia, malnutrition, or a history of gastric reduction and bariatric surgery
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(In rare cases, the abuse of nitrous oxide inhalants)
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Clinical history of painless limb weakness with loss of sensation
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Serum B12 level is low, macrocytic anemia, serum homocysteine ​​is high
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Spinal cord MRI showed abnormal changes in posterior cord and/or corticospinal tract length T2
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8.
A history of copper-deficiency myelopathy malnutrition or gastric reduction and bariatric surgery
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Serum copper is low
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Spinal cord MRI showed abnormal changes in posterior cord and/or corticospinal tract length T2
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Differential diagnosis of optic neuropathy 1.
NMO-related optic neuritis Painful vision loss with or without optic discitis, often with severe symptoms, can be unilateral or bilateral (simultaneous or sequential)
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Accompanied by transverse myelitis
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Intravenous hormone therapy responds well
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MRI showed that the optic nerve was strengthened, but there were no other features consistent with multiple sclerosis
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2.
Multiple sclerosis-related optic neuritis Painful vision loss/decreased color saturation with or without optic discitis, with varying symptoms
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Unilateral is more common, although the contralateral eye can be affected repeatedly later
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There are other clinical features that suggest MS
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MRI showed that in addition to meeting the criteria for diagnosing MS, the lesions may have optic nerve enhancement
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3.
Leber hereditary optic neuropathy is severe, bilateral, sequential painless vision loss, mainly involving the central visual field
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Mitochondrial DNA mutations, mutations are heterogeneous among tissues
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4.
Optic neuritis related to other inflammatory diseases varies in severity and can be bilateral or recurrent
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Peripheral erythema with potential systemic diseases (such as systemic lupus erythematosus, Sjogren’s syndrome, sarcoidosis, Behçet’s disease, etc.
)
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Chronic recurrent inflammatory optic neuropathy (CRION) is a rare idiopathic disease.
Accompanied by severe recurrent optic neuropathy, it can progress to blindness
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5.
Infectious optic neuropathy, tuberculosis, syphilis, Lyme disease, virus/like infectious diseases
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6.
Poisoning and dystrophic optic neuropathy Smoking can aggravate dystrophic optic neuropathy
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Causes of poisoning include CO, methanol, ethylene glycol, and tobacco poisoning
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Toxic optic neuropathy caused by drugs, including ethambutol, isoniazid, colliodone, linezolid, methotrexate, sildenafil and infliximab
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7.
Non-arterial ischemic optic neuropathy painless vision loss, usually in people over 50 years old
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Risk factors for coexisting vascular diseases (hypertension, diabetes, hypercholesterolemia, smoking)
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Fundus examination is usually normal
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8.
Arterial ischemic optic neuropathy painless vision loss, more common in people over 70 years old
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Opticitis can be seen on the ophthalmoscope
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May have clinical manifestations or medical history consistent with superficial temporal arteritis and polymyalgia rheumatica
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Immediate high-dose hormone therapy can prevent further loss of vision
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Summary: Long-segment transverse myelitis (involving 3 or more vertebral segment lengths) is highly indicative of NMO
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The lesions can extend to the brainstem, with clinical manifestations such as refractory hiccups, dysarthria, dysphagia, or respiratory dysfunction
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If a patient with transverse myelitis has brainstem involvement, it is necessary to closely monitor the above complications and provide early supportive treatment
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Severe optic neuritis is manifested as almost complete or complete vision loss, suggesting a potential cause, such as NMO or Leber hereditary optic neuropathy (LHON), etc.
, pay attention to differential diagnosis
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References: [1]Frohman EM,Wingerchuk DM,Clinical practice.
Transverse myelitis.
N Engl J Med,2010,363(6),564-72.
[2]Wingerchuk DM,Lennon VA,Lucchinetti CF,et al.
The spectrum of neuromyelitis optica.
Lancet Neurol 2007;6(9):805-15.
[3]Wu Y,et al.
Neuromyelitis optica spectrum disorder:Pathogenesis,treatment,and experimental models.
Mult Scler Relat Disord 2019 Jan;27.
[ 4]Knight SL,et al.
A retrospective review of the long term clinical outcomes of patients with neurogenic lower urinary tract dysfunction following transverse myelitis.
Neurourol Urodyn 2021 01;40(1).
[5]Zhao Wei et al.
Translated, "Neurology Typical Cases Yun Cui", Tianjin Publishing and Media Group.