Neuroophthalmology for medical students last upgrade 4/2021 Marek Michalec, MD PhD Department of ophthalmology, Faculty Hospital Brno Faculty of medicine, Masaryk University Head: Oldřich Chrapek, Assoc. Prof., MD PhD Content of neuroophthalmology •Visual pathways affections •disorders and affections of optic nerve chiasmatic lesions, postchiasmatic lesions •typical manifestation – decrease of visual acuity and visual field defect •Disorders of oculomotor balance •neurogenic ofi myogenic etiology •typical manifestation - binocular diplopia and paralytic strabismus •Disorders of pupillary reactions •any disorder in any part of pupilomotoric pathway •typical manifestation – anisocoria or abnormality in reaction of pupils • •Note: all disorders mentioned above can be present at same time in various combinations Neuroophthalmological examination I. Medical history •crucial – complete medical history = nearly an half of diagnostic success • •Questions about subjective signs: •Questions: when troubles started, how long last it, any change during time (intermittent / progressive), presence of troubles on fellow eye, personal history, medical history •Common complaints – dominant signs from the patient´s view (i.e. visual acuity decrease, diplopia) •Searching for objective signs: •i.e. pupillary reaction disorders, oculomotor function disorders, ptosis of upper eyelid, red eye •Poor complaints – pacient itself does not be aware with all the signs / troubles • • Neuroophthalmological examination II. General ophthalmological examination •Visual acuity assesment (distance) = central visual acuity (VA) •natural (with no correction = UCVA) and using the best correction of refractive errors (BCVA), monocular, binocular assesment •Basic eye examination •Examination of anterior segment (slit lamp) and posterior segment (direct / indirect ophthtalmoscopy / biomicroscopy) •Focus to exclude possible ophthalmological causes of VA decrease (i.e. corneal scars or opacities, cataract, hemophthalmus, retinal pathologies) •Visual field examination (VF) = perimetry •Crucial examination in neuroophthalmology •Important even with normal VA (good VA does not exclude visual field defects!!!) • Neuroophthalmological examination III. Accessory (interdisciplinary) examination •Internal •basic + specific samling •Neurological •to exclude possible intracranial causes (intracranial expansive lesions, thrombosis, stroke) •to exclude neurological sign of possible neurological diseases (multiple sclerosis) •Endocrinnne •to exclude thyroid disorders (thyroid associated orbitopathy / ophthalmopathy) •to exclude hormonal activity of pituitary gland (pituitary adenoma, chiasmal lesions) • Neuroophthalmological examination IV. Imaging techniques Neurooftalmological examination IV. Imaging techniques Optic nerve characteristics, physiology •Characteristics •2nd cranial nerve •Embryologically part of CNS (together with neural part of retina) •Anterior part of visual pathway •Physiology •Pure senzoric nerve •Every optic nerve = 1.2 million of nerve fibers •80% of nerve fibers - sensoric visual information •20% of nerve fibers - pupilomotoric information (major part of afferent pupilomotor pathway) • • • Optic nerve anatomy •Composition •axons of ganglionic cells •neuroglia •Optic nerve sheaths = sheats of CNS (pia mater, arachnoidea, dura mater) •Anatomical division •Intraocular part •Intraorbital part •Intracanalicular part •Intracranial part •Blood support •Posterior cilliary artery •Ophthalmic artery •Internal carotid artery • • • Optic nerve affections: General characteristics •Typical clinical signs: •Decrease of visual acuity – most prominent sign, usually unilateral, represents the amount of lesion of nerve fibers predominantly from central part of retina (macula) •Visual field defect – represents the amount of lesion of nerve fibers in general •Color vision defect – less prominent but almost always present sign; but not specific (acquired disorder) •Relative afferent pupillary defect (RAPD) – typically unilateral, present of size of affection; due to the affection of afferent part of pupillomotoric pathway • • Pathologies of optic nerve division •1) congenital anomalies •hypoplasia, coloboma, Morning glory syndrom, tilted disc, fibrae medullares, optic disc drusen •2) inflammatory affections - neuritis •demyelinisating, infection, paraneoplastic •3) non-inflammatory affecions - neuropathies •ischaemic, toxic, nutritive •4) Bilateral papiledema •elevation of intracranial pressure zdenek Papiledema clinical picture •Diminished margins of disc •Diminished physiological excavation •Nerve fiber layer oedema •Hyperemia of disc •Dilatation of vessels, tortuosity •Haemorrhagies, cotton wool spots • Papilloedema Physiological appearance •Clinical picture during time •Dynamic state during time •Depends of cause, duration, and therapy • • • • • • • •Example: development in intracranial hypertension (young female), treatment by using acetazolamide. • Papiledema Bilateral papiledema •Etiology •Increase of intracranial pressure and spreading within sheaths •75% of cases – intracranial tumor!!! (frontal lobr or chiasmal area) •Rest of cases – pseudotumor, meningitis, AV malformation, thrombosis •Clinical pisture •Subjective signs: •Short lasting visual impairment (obnubilations) •Headaches (worse in horizonal position) •Objective signs: •Bilateral oedema of optic nerve disc •Enlargement of blind spot – in visual field testing 14-008_CD http://upload.wikimedia.org/wikipedia/commons/1/1a/Papilledema.jpg Optic neuritis Optic neuritis diagnostics •Optical coherence tomography •Accessory examination of MS •Dynamics of changes of RNFL during time •Decrease of RNFL is objective proof of postneuritic atrophy of optic nerve Michalec_RNFL_Obr2.jpg Michalec_RNFL_Obr3.jpg Condition after optic neuritis Left eye (clinically isolated syndrome) Multiple sclerosis Contition after bilateral optic neuritis Michalec_RNFL_obr1.jpg Physiological findings Healthy pacient Optic neuritis diagnosis MRI: optic neuritis http://www.oculist.net/downaton502/prof/ebook/duanes/graphics/figures/v8/1050/004f.gif VEP: delayed latency P100 Anterior ischemic optic neuropathy •most common optic nerve affection in advanced age •unilateral condition •Cause – affection of short ciliary arteries •Epidemiology •50 years of age and more •Clinical picture •loss of visual acuity - fast onset, painless (light perception to almost normal values) •monocular visual field defect – altitudinal scotoma •unilateral ischemic optic disc oedema • prochazkova dolezelova1OS Anterior ischemic optic neuropathy •Arteritic form (10 – 15 % of all cases) – less common, more serious •Risk factors: association with systemic vasculitis (giant-cell arteritis = Horton disease) •Clinical picture: loss on weight, headache, jaw claudication, tenderness and sensitivity on the scalp) •very high sedimentation rate - over 100 per hour, temporal artery biopsy •High risk of affection of fellow eye (days, weeks) – immediate therapy!!! •Therapy: high dosage of intravenous corticoids •Nonarteritic form (85 – 90 % of all cases) •Risk factors: hypertension, diabetes, dyslipidemia, smoking, obesity •Therapy: N/A, compensation of all systemic diseases D:\slides\Neuropathies 14.JPG Temporal artery in GCA Optic nerve atrophy •Irreversible loss of axons •After various optic nerve affections •Etiology •Primary – posttraumatic, by direct pressure of tumor •Secondary – affection of optic nerve (ischemia, inflammation) •Glaucomatous – due to elevated intraocular pressure • •Clinical picture •Pale optic disc •Reduction of smaller vessels http://www.reviewofoptometry.com/CMSImagesContent/2011/11/030_RO1111_F1.gif https://c2.staticflickr.com/8/7254/7602735410_622dcf9a80_m.jpg Anatomy of visual pathway Optic nerve Optic chiasm Optic tract Lateral geniculate body (primary subcortical visual centre) Optic radiation (parietal and temporal lobe) Brodman area 17 (primary visual cortex, occipital lobe) Retina photoreceptor (rod, cone) Bipolar cell (1st neuron) Ganglion cell (2nd neuron) axon of ganglion cell magno-, parvo-, coniocellular cells (3rd neuron) Geniculocalcarine tract fissura calcarina Anatomy of visual pathway – clinical notes •Optical apparapart of eye switch the picture, therefore: •Temporal part of retina process information from nasal part of VF •Nasal part of retina process information from temporal part of VF • •Partial crossing of nerve fibers in optic chiasm: •Nerve fibers originating from temporal part of retina are not crossing and continue on same size of CNS •Nerve fibers originating from nasal part of retina are crossing and continue on opposite size of CNS • •Size lateralisation of visual information in visual cortex: •Right hemisphere process information from left part of VF of both eyes •Left hemisphere process information from right part of VF of both eyes Visual field Visual pathway lesion and visual field defects •Optic nerve lesions •Monocular defects of VF •Lesions in chiasmal area •Usually bilateral heteronymn defects of VF •Lesions of optic tract •Bilateral (incongruent) homonymn defects of VF •Lesions of lateral geniculate body •Bilateral homonymn defects along horizontal line •Geniculocalcarine tract lesions •bilateral congruent* defects of VF • •* Pozn.: congruence – bilateral symmetry of defects of visual field increasing with closer proximity to occipital cortex 1 1 2 2 3 3 4 4 5 5 6 6 7 7 Chiasmal syndrome •lesions in chiasmal area •typically compressive, expansive condition •typical visual field defects – use in diagnosis • •causes: •Pituitary adenomas •Craniopharyngioma •Meningioma •Aneurysm • Pituitary adenoma •benign tumor of pituitary gland •classification • by size – microadenoma (up to 10mm), macroadenoma (more than 10mm) •biological activity – benign adenoma, invasive adenoma, adenocarcinoma •possibility of metabolical activity (e.g. prolactinom) a •compression and lesion of optic chiasm by tumor growth – bitemporal hemianopsia – starting as upper kvadrantanopsia •therapy •conservative – hormone inhibition (Cabergolin, Octreotid) •surgical - resection (endonasal, transsphenoidal adenectomy) • •benign rare type of tumor from pituitary gland embryonal tissue •pressure on nearby tissue, typical visual field defects – bitemporal hemianopsia – first starting as lower quadrantanopsia •therapy •surgical - transsphenoidal adenectomy) •radiotherapy • Craniopharyngioma Meningiomas •slow growing tumor from meninges •tumor growth, pressure on nearby tissue, typical visual field defects depending on location •therapy •surgical •radiotherapy • Anatomy of eye movement system •4 recti muscles: •medial rectus m. •lateral rectus m. •inferior rectus m. •superior rectus m. •2 oblique muscles: •superior oblique m. •inferior oblique m. • Eye movement disorders •Isolated palsies •oculomotor nerve palsy •trochlear nerve palsy •abducent nerve palsy •Ophthalmoplegia •Combination of affection of 2 or 3 nerves •cavernous sinus syndrome •orbital apex syndrome •carotido-cavernous fistula • • Isolated palsies - causes •Oculomotor nerve palsy – aneurysm (most common), less common tumor, trauma, ischemia (diabetic neuropathy) •Trochlear nerve palsy – trauma (fall on head; most common sign), ischemia of brainstem, tumor, half of cases idiopathic •Abducens nerve palsy – trauma (most common), ischemia (diabetic neuropathy), intracranial hypertension (sometimes first manifestation), meningitis, tumor in close proximity of brainstem, idiopathic • • Oculomotor nerve palsy •Upper eyelid ptosis •Convergence insufficiency •Eye movement disorder – in multiple sizes of gaze (nasal, up, down) •Diplopia (mixed – horizontal and vertical) •Anisocoria (mydriasis on affected size) Trochlear nerve palsy •Diplopia – vertical, major manifestation in downgaze or walking downstairs) •Eye movement disorder – affected eye with small hypertropia, not necessary visible! •Compensation head posture (Torticollis) – chin turning down, head posture at non affected size • Abducens nerve palsy •Diplopia – typically horizontal, major manifestation in gaze to affected size •Eye movement disorder – insufficiency of movement laterally (insufficiency of abduction) •Compensation head posture – head turned laterally on affected size Cavernous sinus syndrome •Etiology •Compressive / infiltrative lesion in cavernous sinus (thrombosis, tumor, metastasis, aneurysm) •Lesion of multiple oculomotor nerves (oculomotor, trochlear, abducens) and trigeminal •Absence of optic nerve lesion, therefore the onset of diplopia • • • meningioma Clinical picture •Upper eyelid ptosis (oculomotor nerve palsy) •ophthalmoplegia (oculomotor nerves palsy) •diplopia (no affection of optic nerve) •Mydriasis (oculomotor nerve palsy) •exophthalmus (oculomotor nerves palsy) •Trigeminal pain • • • Orbital apex syndrome •Etiology •Compressive / infiltrative lesion in the orbital apex (tumor, metastasis, inflammation) •Lesion of oculomotor, trochlear, abducens nerve and also optic nerve •Clinical picture •Upper eyelid ptosis (oculomotor nerve palsy) •Ophthalmoplegia (multiple oculomotor nerves palsy) •Decrease of visual acuity (affection of optic nerve) •Exophthalmus (multiple oculomotor nerves palsy) •Absence of diplopia (the more severe lesion of optic nerve, the lower presentation of diplopia) •Trigeminal pain • Aspergillus infection Pupillary reactions •Physiological appearance of pupils •Shape •Always round and regular pupil even in dark or light •Size •isocoria – equal size of pupils •under fotopic conditions - miosis •Under photopic conditions - mydriasis •physiological anisocoria – inequal size of pupils up to 1mm; cca 20% of population •Difference in size is usually preserved even in dark or light •Dependence of size of pupils: •Autonomous nervous sytem (i.e. anxiety, fear, stress, rest, sexual excitation…) •Medication, drugs • Pupillary reactions •Physiological reactions of pupil • •Mydriasis (wide pupil) •Sympathetic part (innervation - dilatator muscle) •miosis (narrow pupil) •Parasympathetic part (innervation - sphincter muscle) •Consensual reaction of both pupil even in the case of enlightenment of one pupil only Pupillary reaction diagnostic testing •Photoreaction testing •Reaction to direct and indirect enlightenment – physiological miosis of both pupils at same time •Test near response •Testing of accomodation-convergence reflex •Physiological miosis associated with convergence and accomodation (fixation to object moving closer to eyes) •Pharmacological testing •Diagnosis of anisocoria Stav po embolizaci Pupillary reactions Diagnostic testing •Test swinging flashlight •diagnosticic testing for presence of relative afferent pupillary defect (RAPD) – lesion of visual filed is shared with afferent part of pupilomotoric pathway; typical for unilateral lesion of optic nerve •Principle: change of enlightenment of one pupil, followed by the other pupil with latency (circa 2 seconds) – this is necessary for mydriasis restoration and observation of reactions: •1) both pupils with mydriasis in dark •2) enlightenment of one (presumed normal) pupil only – fast miosis of both pupils •3) enlightenment of fellow (presumed pathological) pupil – slower / abnormal reaction of both pupils (presence of RAPD) •4) repeated enlightenment of normal pupil – normal reaction with fast miosis of both pupils • • Stav po embolizaci 1 2 3 4 Reactions of pupil •Atypical size or reactions of pupil •Pupilotonia (Adie´s pupil) •Wider (mydriasis) pupil with small or no reaction to light •Worm-like movement of pupillary margin (using slit lamp) •Accomodation failure (VA decrease to near distance) •Decreased / diminished tendon reflexes (patellar, Achilles) •Argyll-Robertson pupil •Narrow pupil with no additional rection to light •Preservation of accomodation •Typically for patients with neurosyphillis, neuropathies, diabetic polyneuropathies •Anisocoria •Inequal size of pupils (usually more than 1mm) Anisocoria diagnostic method light dark •1) Exclusion of various possible ophthalmological causes: •Plegia of pupil after ocular trauma (contusion, perforating trauma) •Anomalies of shape (i.e. congenital or acquired coloboma or anomaly, recurrent iridocyclitis – posterior synechiae) •Complications after intraocular surgery (mostly cataract surgery) or intraocular inflammation (endophthalmitis) •2) Assessment of pathological pupil •Size of pupil in light (wider pupil is pathological) •Size of pupil in dark (narrowet pupil is pathological) Pathological pupil Anisocoria – diagnostic method Stav po embolizaci light dark 10% cocaine Horner´s syndrome Physiological anisocoria 0,1% Pilocarpine Adie´s pupil 1-2% Pilocarpine Oculomotor nerve palsy Arteficial mydriasis Horner´s syndrome •Etiopathogenesis •Lesion of sympathetic pupilomotorpathway • •Signs •Miosis of pupil (no mydriasis in dark) – dilatator muscle palsy •Upper eyelid ptosis (usually mild) and pseudoenophthalmus – tarsal muscle palsy •anhidrosis (diminished sweating on affected size / half of face) •heterochromia (congenital form only) – failure of chromatophores creation • Stav po embolizaci Horner´s syndrome •Etiology •50% idiopathic •50% various causes •Trauma /surgery in cranial /cervical / upper thoracal area •Dissection of internal carotid artery •Brainstem ischemia •Multiple sclerosis •intracranial tumors (various locations) •Spinal cord (syringomyelia) •Pancoast tumor (lung apex tumor) •Thyroid diseases (goiter, carcinoma) Angiografie: komunikace - fistula Stav po embolizaci http://www.ib.cnea.gov.ar/~redneu/2013/BOOKS/Principles%20of%20Neural%20Science%20-%20Kandel/gatewa y.ut.ovid.com/fulltextservice/ct%7B06b9ee1beed594190674f1983457a7dd32af6a0d5a4c9892~53/da7c45ff14.g if.png Thank you for your attention! http://upload.wikimedia.org/wikipedia/commons/thumb/9/9d/Example_of_Horner%27s_syndrome_in_a_cat.jp g/800px-Example_of_Horner%27s_syndrome_in_a_cat.jpg