Tag Archives: Visual disturbance

Kearns-Sayre Syndrome KSS

Clinical features: Onset before 20 years of age. Progressive external opthalmoplegia (restricted eye movements, usually movements are not dysconjugated) and pigmentory retinopathy. Also myopathy, heart block, CNS deficits, short stature. Pathology: Muscle biopsy: Gomori trichrome: Ragged red fibres Variation in muscle size COX negative fibres Brainstem and cerebellum: neuronal loss. Spongy to vacuolar myelinopathy. May … Continue reading Kearns-Sayre Syndrome KSS

Cranial Neuropathies

Here are some lists to help with the cranial neuropathies. Please see the underlying sections. Also see the section on vertigo for cranial nerve VIII diseases. Synonyms: Cranial neuropathy Causes of Oculomotor nerve palsy (CN III): think of anatomy Nuclear & fasciular: Tumours: Glioma Part of a brainstem stroke syndrome Basilar area: Meningitis: Bacterial, Meningovascular … Continue reading Cranial Neuropathies

Diabetic Neuropathy

There are various types of diabetic neuropathy Diabetic polyneuropathy (sensory type and sensorimotor type): Diagnosis: Features of polyneuropathy and meeting criteria for diabetes mellitus Clinical features: Symmetric sensory polyneuropathy, loss of vibration, pain, touch and temperature sensation and in some cases proprioception loss and Charcot joints Areflexia Painful May become sensorimotor Pathology, nerve biopsy: Nonspecific … Continue reading Diabetic Neuropathy

Giant Cell Arteritis

Synonyms: a.k.a. cranial arteritis a.k.a. temporal arteritis: Diagnosis: Biopsy of the temporal artery within 7 days of starting steroids: With serial sectioning Or clinical features plus raised ESR or CRP plus response to steroids Pathology: Panarteritis: Intimal thickening and proliferation, Lymphocytic infiltration of media and adventitia, giant cells, Disruption of elastic lamina Chronic phase: intimal … Continue reading Giant Cell Arteritis

Acquired Oculomotor Apraxia

Synonyms: a.k.a. Roth-Bielschowsky syndrome (supranuclear palsy of gaze due to corticotectal/corticotegmental tract lesions) Diagnosis: A form of supranuclear palsy diagnosed clinically and by isolating the underlying cause Clinical features: Inability to perform horizontal saccades Vertical eye movements may be intact Oculocephalic reflexes are intact Caloric testing shows slow deviation without saccades Optokinetic nystagmus remains without … Continue reading Acquired Oculomotor Apraxia

Superior Orbital Fissure Syndrome

Synonyms: Anterior cavernous sinus syndrome, Rochon-Duvigneaud’s syndrome Diagnosis: This is a clinical diagnosis. Underlying causes are identified by investigations and clinical assessment. Dysfunction of cranial nerves oculomotor (III), trochlear (IV), abducens (VI) and first division of the trigeminal nerve (V1). Also sympathetic fibers may be involved causing a Horner syndrome (this becomes cavernous sinus syndrome). … Continue reading Superior Orbital Fissure Syndrome

Cavernous Sinus Syndrome

Diagnosis: This is a clinical diagnosis. Dysfunction of cranial nerves III, IV, and VI, and the superior divisions of cranial nerve V. Investigations to consider: Blood tests: FBC, U&E, fasting Glucose Vasculitic screen, ESR, CRP, ANCA, ANA, ENA SPEP, ACE Tests for infections: Borrelia serology, HIV MRI pre and post contrast: Pituitary tumors, meningioma, metastasis … Continue reading Cavernous Sinus Syndrome

Internuclear Ophthalmoplegia (INO)

Diagnosis: This is a clinical diagnosis. The underlying cause is determined by investigations Clinical features: Diplopia Classic variant, posterior INO: On lateral gaze: Failure of adduction of the contralateral eye, nystagmus of the abducting eye Medial rectus is less weak on testing each eye separately Anterior INO variant: Divergent eyes bilaterally, paralysis of both medial … Continue reading Internuclear Ophthalmoplegia (INO)

Abducens (cranial nerve VI palsy)

Diagnosis: This is a clinical diagnosis Clinical features: Horizontal diplopia In neutral gaze, normal appearance or head is slightly turned to the unaffected side (compensation for unopposed medial rectus) On movement: Affected eye fails to abduct Investigations to consider: Blood tests: ESR: giant cell arteritis TFT, glucose ANCA: Wegner’s granulomatosus HbA1c ESR CT: Out rules … Continue reading Abducens (cranial nerve VI palsy)

Trochlear Nerve Palsy (Cranial IV palsy)

Diagnosis: This is a clinical diagnosis Clinical features: Rare in isolation In neutral gaze: slight head tilted contralateral to the weak superior oblique muscle (loss of in-torsion) Test with eye adducted and moved inferiorly. This is also the position of worse diplopia If bilateral: on horizontal gaze, the abducting eye drifts downwards (inferior rectus of … Continue reading Trochlear Nerve Palsy (Cranial IV palsy)

Oculomotor Palsy (cranial nerve III palsy)

Synonyms: a.k.a. III nerve palsy Diagnosis: This is a clinical diagnosis. The underlying cause requires investigations. Clinical features: In neutral gaze: The eye is looking down & out. There is complete ptosis. On looking downwards torsional (in-torsion) nystagmus of the eye occurs (due to intact IV nerve action) Note the presence of meiosis: Normal pupil … Continue reading Oculomotor Palsy (cranial nerve III palsy)

Cancer-associated retinopathy (CAR)

Diagnosis: A paraneoplastic syndrome. diagnosed based on clinical features, associated antibodies, perimetry and identification of the underlying neoplasm Clinical features: Rapid visual loss Anti CAR antibodies (VPS, Anti-Recoverin): raised Goldmann perimetry: ring-like scotoma in each eye Investigations to consider: CT chest abdomen & pelvis: lung cancer Related articles: Approach to visual deficits, Optic neuritis,

Leukoencephalopathy (white matter disease)

Damage to white matter may occur due to may conditions that can affect the brain. The clinical features, prognosis and treatment are related to the underlying condition Clinical features: There is a wide range of symptoms: Rapidly progressive dementia/subacute encephalopathy, lower body parkinsonism/gait apraxia, behavioural changes, pseudobulbar speech and pseudobulbar affect may occur Later on … Continue reading Leukoencephalopathy (white matter disease)

Biotin-Responsive Encephalopathy

Diagnosis: Clinical features, laboratory testing and MRI Clinical features: Ophthalmoplegia, nystagmus, ataxia, diplopia and ptosis Complex partial seizures with status epilepticus. Thiamine-responsive Genetics: Thiamine-Transporter Gene Findings on Investigations: MRI: High-intensity signals in the bilateral medial thalamus Laboratory: Thiamine levels: normal Treatment: Thiamine Related articles: Approach to cognitive impairment, approach to acute confusion, approach to diplopia, … Continue reading Biotin-Responsive Encephalopathy

Optic Neuritis

Diagnosis: Clinical features with or without imaging or physiological tests Clinical features: Painful, loss of vision, & loss of accurate colour vision (dyschromatopsia) Fundoscopy: swollen optic disc (optic disc edema, this is not papilledema because pressure is normal), Relative afferent papillary defect Findings on Investigations: MRI: T2 fat suppressed, high signal foci in the optic … Continue reading Optic Neuritis

Neuromyelitis Optica

Synonyms: a.k.a. Devic’s disease Diagnosis: A combination of clinical features, NMO-IgG antibodies and imaging Clinical features: simultaneous or sequential occurrence of optic neuritis and myelitis (usually acute complete transverse myelitis). Findings on Investigations: MRI: Spinal cord lesion =or> 3 segments long Non-diagnostic for Multiple sclerosis White matter lesions that are long & extend from the … Continue reading Neuromyelitis Optica


Diagnosis: Suggested by MRI and confirmed by pathology (brain biopsy/resection) Findings on Investigations: Eye, optic nerve, pineal gland Pathology: Grossly: White tan mass Histology: Small round blue cells, rosette (Homer-Wright around neuritic processes & Flexner-Wintersteiner around a central lumen), necrosis, frequent mitosis Immunohistochemistry: NSE, NeuN, synaptophysin Genetics: RB gene mutation 13q14, germline. Related articles: Brain … Continue reading Retinoblastoma

Susac’s syndrome

Synonyms: Retinocochleocerebral vasculopathy Diagnosis: Clinical: Encephalopathy (including psychosis), monocular vision loss, hearing loss Headache Branch retinal artery occlusion MRI: T2 hyperintensity in basal ganglia, thalamus, white matter (almost always involving corpus callosum). May involve brainstem & cerebellum T1 +contrast: leptomeningeal enhancement & parenchymal enhancement Ophthalmic fluorescein angiography: Retinal vasculitis: narrowing, occlusion, vessel wall hyperfluorescence, contrast … Continue reading Susac’s syndrome

Ischemic Stroke

Ischemic stroke is the commonest form of stroke. It represents infarction of the brain or spinal cord due to interruption of blood supply. There are many causes including embolism of material such as thrombus, cholesterol or rarely other material. Other mechanisms include thrombosis and miscellaneous causes of interruption of blood flow. The symptoms vary depending … Continue reading Ischemic Stroke

Tuberculous Meningitis

Synonyms: Mycobacterium tuberculosis meningitis, TB meningitis, tuberculoma, tuberculous meningovasculitis Diagnosis: Clinical features plus confirmatory CSF analysis or TB studies Findings in Investigations: Findings remain after 10 days treatment White cell count: moderately high, Usually <500/microL, (100-300/mm3) Mainly lymphocytes Protein: High, >0.8g/L Glucose: Low ,<2.2 mmol/l Or atypically: Neutrophilia if early, normal protein, normal glucose Eosinophilia … Continue reading Tuberculous Meningitis

Nerve diseases

Please start with the section on neuromuscular disease patterns for an introduction. Once you determined that the patient likely has a nerve disease you will need to consider which type to narrow down the differential diagnosis. As described in the previous section determining which of the main patterns cranial neuropathy, mononeuropathy, radiculopathy, polyneuropathy, mononeuropathy multiplex, … Continue reading Nerve diseases

Multiple Sclerosis

This is an autoimmune disease of the central nervous system white matter. There is some evidence that the grey matter may be involved in the disease, but it is best to think of it as a type of white matter disease. The disease is multifocal i.e. it affects non-adjacent parts of the white matter. The … Continue reading Multiple Sclerosis