Nervous and sensory conditions

Neonatal brainstem dysfunction

Neonatal brainstem dysfunction is a rare neurologic disorder of newborns marked by impaired suction and swallowing, obstructive apnea, medication-resistant gastroesophageal reflux, and cardiac vagal overactivity with bradycardia.

Neonatal cerebral ischaemia

Neonatal cerebral ischaemia (ICD-11 KB00; ICD-10 P91.0) is insufficient cerebral blood flow in newborns, subdivided into perinatal arterial stroke and neonatal sinovenous thrombosis; NAIS causes about 80% of perinatal strokes.

Neonatal hydrocephalus

Neonatal hydrocephalus, also called infantile or congenital hydrocephalus, is excess cerebrospinal fluid in a newborn's brain ventricles with raised pressure; causes include prematurity-related hemorrhage, infection, and L1CAM and other genetic forms, treated by shunt or ETV.

Neonatal meningitis

Neonatal meningitis: bacterial infection of the meninges and CSF in newborns (first 28 days, often considered to 90 days). Caused mainly by GBS, E. coli, Listeria; fatality 10–15% in high-income versus 40–58% in low-income settings.

Neonatal seizures

Neonatal seizures: seizures in newborns (first 28 days, up to 44 weeks PMA), 1–5 per 1000 live births, mostly acute provoked by HIE, stroke, infection; diagnosed by EEG; phenobarbital first-line.

Neovascular glaucoma

Neovascular glaucoma (NVG), also called rubeotic glaucoma, is a severe secondary glaucoma from iris and angle neovascularization driven by retinal ischemia, mainly diabetic retinopathy and central retinal vein occlusion, treated with anti-VEGF, PRP, and glaucoma surgery.

NESCAV syndrome

NESCAV syndrome, formerly autosomal dominant intellectual disability type 9, is a rare neurodegenerative KIF1A disorder beginning in infancy, causing developmental delay, absent speech, and progressive lower-limb spasticity.

Neuralgia

Neuralgia, nerve pain along a nerve's distribution; major forms are trigeminal neuralgia (tic douloureux), postherpetic neuralgia, and occipital neuralgia. TN incidence 12.6/100,000 person-years; carbamazepine first-line; microvascular decompression most effective surgery.

Neuralgic amyotrophy

Neuralgic amyotrophy, also called Parsonage-Turner syndrome or brachial neuritis, is a painful peripheral nerve disorder with sudden shoulder pain followed by weakness, atrophy, and sensory loss; idiopathic or autosomal dominant hereditary (SEPTIN9) forms.

Neurenteric cyst

A neurenteric cyst, also called an enterogenous or enteric cyst, is a rare congenital lesion lined by gut-like epithelium, usually ventral to the spinal cord, treated by surgical resection.

Neuroblastoma

Neuroblastoma, also called INRG-stage childhood sympathetic cancer, is the most common extracranial solid tumor of childhood, arising from adrenal medulla and paraspinal neuroblasts; risk-stratified by MYCN amplification and INRGSS, with survival from 98% (low-risk) to about 60% (high-risk).

Neurocutaneous melanocytosis

Neurocutaneous melanocytosis (NCM, neurocutaneous melanosis) is a rare congenital phakomatosis with CNS melanocyte deposits plus large or multiple congenital melanocytic nevi, caused by postzygotic NRAS codon 61 mutations, symptomatic in one-third to one-half of cases.

Neurodegeneration due to 3-hydroxyisobutyryl-CoA hydrolase deficiency

HIBCH deficiency (OMIM 250620), an ultrarare autosomal recessive valine catabolism disorder caused by HIBCH gene mutations, causing Leigh-like neurodegeneration, hypotonia, seizures, elevated C4-OH carnitine, treated with valine-restricted diet.

Neurodegenerative disease

Neurodegenerative disease is a progressive disorder of the brain or peripheral nervous system that leads to nerve cell death. While some treatments can slow progression, no cure currently exists.

Neurodevelopmental delay-intellectual disability-skeletal defects syndrome

Neurodevelopmental delay-intellectual disability-skeletal defects syndrome, also called HNRNPH2-related neurodevelopmental disorder or Bain type X-linked syndromic intellectual disability, is a rare X-linked dominant disorder from HNRNPH2 missense variants at Xq22.1, causing universal developmental delay, intellectual disability, and frequent scoliosis and foot deformities.

Neurodevelopmental disorder

Neurodevelopmental disorders (NDDs) are DSM-5 conditions with onset in the developmental period, including intellectual disability, autism spectrum disorder, ADHD, communication, motor, and learning disorders, affecting about 1 in 6 US children.

Neuroectodermal melanolysosomal disease

Neuroectodermal melanolysosomal disease, also known as Elejalde syndrome, is a rare autosomal recessive disorder with silvery hair, seizures, and severe neurological impairment, first described in 1979.

Neuroferritinopathy

Neuroferritinopathy (hereditary ferritinopathy, NBIA3) is a rare autosomal dominant adult-onset movement disorder from FTL ferritin light chain mutations, causing brain iron accumulation, chorea or dystonia, low serum ferritin, and basal ganglia cavitation on MRI.

Neurofibroma

Neurofibroma: benign peripheral nerve sheath tumor of Schwann cell origin, named by von Recklinghausen in 1882; occurs sporadically or in NF1, with dermal and plexiform subtypes, treated by surgery or selumetinib.

Neurofibromatosis type 3

Neurofibromatosis type 3 (NF3), ICD-11 code LD2D.12, is a legacy designation for a third neurofibromatosis form; historically the mixed type (Riccardi 1982), later segmental (Carey 1986), now outside the NF1/NF2-related schwannomatosis/schwannomatosis framework.

Neurogenic arthrogryposis multiplex congenita

Neurogenic arthrogryposis multiplex congenita (ORPHA:1143, OMIM 208100, 618766) is a rare autosomal recessive AMC subtype with neonatal onset, caused by motor neuron or peripheral nerve defects leading to fetal akinesia, multiple joint contractures, and neurogenic muscle atrophy; genes include DST, ZC4H2, DYNC1H1, KIF21A.

Neurological Diagnostic Techniques

Neurological diagnostic techniques: neurological examination, blood, genetic, and CSF tests, MRI and CT imaging, EEG, EMG, nerve conduction, evoked potentials, and angiography used to diagnose brain, spinal cord, and nerve disorders.

Neurological examination

Neurological examination: structured clinical assessment of brain, spinal cord, nerves, and muscle receptors; components include mental status, cranial nerves, motor, sensory, reflexes; modern form 1850–1914; NIHSS quantifies stroke severity.

Neurolymphomatosis

Neurolymphomatosis (NL): rare infiltration of peripheral nerves, roots, plexuses, or cranial nerves by malignant lymphocytes, usually non-Hodgkin lymphoma; painful asymmetric neuropathy, diagnosed by biopsy and FDG-PET/MRI, median survival 18 months.

Neuroma of amputation stump

Neuroma of amputation stump, or amputation neuroma, is a disorganized mass of regenerating nerve fibers that forms at a severed nerve end after amputation, causing localized residual limb pain.

Neuromuscular disease

Neuromuscular disease: disorders of motor neurons, peripheral nerves, the neuromuscular junction, or muscle, causing weakness. Includes ALS, SMA, myasthenia gravis, CMT, and muscular dystrophies; treated with multidisciplinary care and new AAV gene therapies.

Neuromyelitis optica spectrum disorder

Neuromyelitis optica spectrum disorder (NMOSD, Devic disease) is a rare relapsing autoimmune astrocytopathy of the CNS driven by AQP4-IgG in over 80% of cases, diagnosed by 2015 IPND criteria and treated with methylprednisolone, plasma exchange, and approved biologics.

Neuromyotonia

Neuromyotonia, also called Isaacs' syndrome or acquired autoimmune neuromyotonia, is a peripheral nerve hyperexcitability disorder with continuous muscle fiber activity, CASPR2/VGKC antibodies, thymoma association, EMG neuromyotonic discharges, and Morvan syndrome as its CNS variant.

Neuronal intranuclear inclusion disease

Neuronal intranuclear inclusion disease (NIID) is a rare progressive neurodegenerative disease with eosinophilic intranuclear inclusions, caused by GGC repeat expansion in NOTCH2NLC; tremor, dementia, and a DWI U-fiber MRI sign are typical.