92 Argyll Robertson pupils Neurosyphilis Very rarely, may cause unilateral miosis Advanced age MAO: monoamine oxidase. Diplopia Monocular Diplopia This condition may be psychogenic, or may be due to a refractive distur- bance in the eye. Astigmatism or opacity of the cornea or lens Corneal dystrophy Iridodialysis Foreign body (e.g., air bubbles, glass, parasites) Large retinal tear Retinal macular cyst Occipital lobe lesions Tonic conjugate gaze deviation Lack of correspondence between the frontal eye fields and occipital associative areas Palinopsia Binocular Diplopia If double vision is relieved by occlusion of either eye, it is due to malalignment of the visual axes. Extraocular muscle disorders Myasthenia gravis Thyroid orbitopathy Orbital apex trauma with connective tissue and muscle entrapment Orbital myositis Neuro-Ophthalmology Tsementzis, Differential Diagnosis in Neurology and Neurosurgery © 2000 Thieme All rights reserved. Usage subject to terms and conditions of license. 93 Tumors E.g., pituitary adenoma and growth hormone –secret- ing adenoma. The tumors cause enlargement of the extraocular muscles Oculomotor nerve dis- orders Severe head trauma E.g., sphenoid fractures (orbital apex) affect the oculo- motor nerves, temporal bone fractures affect cranial nerves VI and VII Microvascular ischemia Associated with diabetes mellitus Compression – Tumor Meningioma, pituitary adenoma with apoplexy, metastases (particularly from nasopharyngeal carci- noma) – Giant intracranial aneurysm Increased intracranial pressure E.g., uncal and tonsillar herniation affecting cranial nerves III and VI Meningeal infection, basal inflammation and carcinomatosis Central pathway dis- orders Internuclear ophthal- moplegia A lesion of the medial longitudinal fasciculus (MLF) be- tween cranial nerves III and VI produces disconjugate eye movements and diplopia on lateral gaze Skew deviation This is thought to represent damaged otolithic inputs. It occurs frequently with unilateral MLF lesions, but may also occur in many brain stem lesions. Usually, the higher eye is on the side of the lesion Divergence insuffi- ciency E.g., bilateral sixth cranial nerve palsies, increased in- tracranial pressure Convergence insuffi- ciency E.g., convergence spasm suggested by associated miosis due to the near response Decompensated stra- bismus Usually of no pathological importance Optical system disorders Nuclear lens sclerosis Uncorrected refractory error Corneal disease – Keratoconus E.g., Gorlin–Goltz syndrome or focal dermal hypo- plasia, Crouzon’s disease – Megalocornea E.g., Marfan’s syndrome, Pierre Robin’s syndrome – Microcornea E.g., Bardet–Biedl syndrome Diplopia Tsementzis, Differential Diagnosis in Neurology and Neurosurgery © 2000 Thieme All rights reserved. Usage subject to terms and conditions of license. 94 Peripheral iridectomy Disorders of the lens – Dislocated lens E.g., Alpor t’s syndrome, Marfan’s disease – Spherophakia E.g., hyperlysinemia, sulfite oxidase deficiency Unclear or combined disorders Chronic progressive ex- ternal ophthalmoplegia Toxic ophthalmoplegia E.g., botulism and diphtheria Miller–Fisher syndrome, Guillain–Barré syn- drome E.g., postviral neuropathy Metabolic E.g., Wernicke’s encephalopathy Eaton–Lambert myas- thenic syndrome Myotonic dystrophy MLF: medial longitudinal fasciculus. Vertical Binocular Diplopia Blowout fracture of orbital floor with entrapment of the inferior rectus muscle Thyroid orbitopathy with tight inferior rectus muscle Ocular myasthenia Cranial nerve III (oculomotor) palsy Cranial nerve IV (trochlear) palsy Skew deviation Horizontal Binocular Diplopia Blowout fracture of medial orbital wall and entrapment of the medial rectus muscle Thyroid orbitopathy with tight medial rectus muscle Ocular myasthenia Internuclear ophthalmoplegia Convergence insufficiency Decompensated strabismus Cranial nerve III (oculomotor) palsy Cranial nerve VI (abducens) palsy Neuro-Ophthalmology Tsementzis, Differential Diagnosis in Neurology and Neurosurgery © 2000 Thieme All rights reserved. Usage subject to terms and conditions of license. 95 Ptosis Congenital Isolated Drooping is unilateral in 70% of congenital ptosis cases Familial Very rare, bilateral Sympathetic denerva- tion Congenital Horner’s syndrome Anomalous synkinesis between cranial nerves III and V Marcus Gunn phenomenon, jaw winking Blepharophemosis syn- dromes Neonatal myasthenia Neurogenic E.g., due to third nerve lesions Nuclear lesions Severe bilateral ptosis, medial rectus weakness, up- ward gaze paresis and pupillary dilation if the lesion is complete Peripheral lesions Unilateral ptosis, mydriasis, and ophthalmoplegia Myopathy Myasthenia gravis Oculopharyngeal muscular dystrophy Chronic progressive ex- ternal ophthalmoplegia Polymyositis Chronic use of topical steroid eye drops/oint- ment Orbit Inflammatory disease – Thyroid orbitopathy – Idiopathic orbital in- flammatory disease Orbital pseudotumor – Tolosa–Hunt syn- drome – Orbital ape x syn- drome Painful ophthalmoplegia Tumors Infantile rhabdomyosarcoma, dermoid cyst, heman- gioma, metastatic neuroblastoma, optic glioma Ptosis Tsementzis, Differential Diagnosis in Neurology and Neurosurgery © 2000 Thieme All rights reserved. Usage subject to terms and conditions of license. 96 Trauma Iatrogenic, especially after surgery for strabismus, reti- nal detachment, and cataract Pseudoptosis Secondary to ocular irri- tations, foreign body (e.g., protective) Blepharospasm Enophthalmos Pathological contra- lateral lid retraction Contralateral exoph- thalmos Huntington’s chorea (lid-opening apraxia) Hysterical Acute Ophthalmoplegia Unilateral Aneurysm or anomalous vessels The nerve palsy is considered to be due to hemor- rhage, either within the aneurysmal sac to which the nerve is adherent, or directly into the nerve – Oculomotor nerve palsy Aneurysms at the junction of the posterior communi- cating and internal carotid arteries – Abducens nerve palsy Aneurysm of the anterior inferior cerebellar artery and basilar artery Small brain stem hemorrhages E.g., emboli, leukemia, blood coagulopathies Ophthalmoplegic migraine Transitory palsy affecting the oculomotor nerve in 85% of cases, and the abducens and trochlear nerves in only 15% Cavernous sinus throm- bosis Originating almost exclusively from spread of infection from the mouth, nose, or face Inferior petrosal sinus thrombosis (Gradenigo syndrome) Originating from infections of the middle ear and af- fecting the abducens nerve, facial nerve, and trigemi- nal ganglion Cavernous sinus fistula Traumatic in origin Neuro-Ophthalmology Tsementzis, Differential Diagnosis in Neurology and Neurosurgery © 2000 Thieme All rights reserved. Usage subject to terms and conditions of license. 97 Brain tumors Brain stem glioma, craniopharyngioma, pituitary ade- noma, nasopharyngeal carcinoma, lymphoma, pineal region tumors Idiopathic cranial ner ve palsy Transitory nerve palsy, attributed to a viral infection and affecting the abducens nerve more often than the oculomotor or trochlear nerves Myasthenia gravis And other pharmacological or toxic causes of neuro- muscular blockade Orbital – Tumors Dermoid cyst, hemangioma, metastatic neuroblas- toma, optic glioma, rhabdomyosarcoma – Inflammatory dis- ease Tolosa–Hunt syndrome, orbital pseudotumor, sarcoid Trauma E.g., blowout fracture of the orbit with entrapment myopathy Increased intracranial pressure E.g., uncal herniation, pseudotumor cerebri Demyelination E.g., fascicular, affecting all three nerves Bilateral Most of the conditions causing unilateral acute oph- thalmoplegia may also produce bilateral ophthal- moplegia Botulism Intoxication Ocular motility may be impaired by drugs such as anti- convulsants, tricyclic antidepressants, and other psy- chotropic medications at toxic serum concentrations Encephalitis of the brain stem Caused by echovirus, coxsackievirus, and adenovirus Diphtheria Cavernous sinus throm- bosis Caroticocavernous fistula Myasthenia gravis, thyrotoxicosis Acute Ophthalmoplegia Tsementzis, Differential Diagnosis in Neurology and Neurosurgery © 2000 Thieme All rights reserved. Usage subject to terms and conditions of license. 98 Internuclear Ophthalmoplegia This is a disorder of horizontal eye movements due to a lesion of the me- dial longitudinal fasciculus (MLF) in the mid-pons, between the third and sixth cranial nerves. The MLF lesion produces disconjugate eye movements and diplopia on lateral gaze, since impulses to the lateral rectus travel abnormally, whereas those to the medial rectus are intact. Brain stem infarction Most common in the older population; the syndrome is unilateral, and is caused by occlusion of the basilar artery or its paramedian branches Multiple sclerosis Most common in the young adults, especially when the syndrome is bilateral Intrinsic and extra-axial brain stem and fourth ventricular tumors E.g., glioma, metastasis Brain stem encephalitis E.g., viral or other forms of infection Drug intoxication E.g., tricyclic antidepressants, phenothiazines, barbitu- rates, phenytoin Metabolic en- cephalopathy E.g., hepatic encephalopathy, maple syrup urine dis- ease Lupus erythematosus Head trauma Degenerative condi- tions E.g., progressive supranuclear palsy Syphilis Chiari types II and III malformation and as- sociated syringobulbia Pseudointernuclear ophthalmoplegia As a feature of myasthenia gravis, Wernicke’s en- cephalopathy, Guillain–Barré syndrome, exotropia, Fisher’s syndrome Neuro-Ophthalmology Tsementzis, Differential Diagnosis in Neurology and Neurosurgery © 2000 Thieme All rights reserved. Usage subject to terms and conditions of license. 99 Vertical Gaze Palsy Tumors – Pineal area – Midbrain – Third ventricle Aqueduct stenosis and hydrocephalus Infarction or hemorrhage of the dorsal midbrain Head trauma Multiple sclerosis Miller–Fisher syndrome Vitamin B 12 or B 1 deficiency Neurovisceral lipid storage diseases – Gaucher’s disease – Niemann–Pick disease, type C Congenital vertical oculomotor apraxia The syndrome can be mimicked by: – Progressive supranuclear palsy – Thyroid ophthalmopathy – Myasthenia gravis – Guillain–Barré syndrome – Congenital upward gaze limitation Unilateral Sudden V isual Loss Vascular disturbances Ischemic optic atrophy due to arteriosclerosis Pallor of the optic nerve head, pale retinas, pseudo- papilledema and incomplete blindness are the promi- nent diagnostic features Transient monocular blindness or amaurosis fugax Stenosis of the internal carotid artery or cardiogenic emboli are mainly responsible Temporal arteritis Affects elderly individuals, and frequently leads to complete blindness; patients complain of headaches, and the ESR is usually raised Unilateral Sudden Visual Loss Tsementzis, Differential Diagnosis in Neurology and Neurosurgery © 2000 Thieme All rights reserved. Usage subject to terms and conditions of license. 100 Bilateral Sudden Visual Loss Cortical blindness Loss of vision with preservation of the pupillary light reflex and normal ophthalmoscopic examination Transient blindness Mild head trauma, migraine, hypoglycemia, hypoten- sion Acute retrobulbar neuritis Acute inflammatory re- action of the optic nerve in response to: – Multiple sclerosis Up to 50% of cases have other manifestations of mul- tiple sclerosis – Metabolic and toxic insults – Birth control pill Patients complain of impairment of central vision (e.g., “puff of smoke,” “fluffy ball”). The examination re- veals impaired visual acuity (20/200), a cen- tral scotoma, and occa- sionally papilledema (when the inflamma- tion is just behind the nerve head) Differential diagnosis – Papilledema (due to the severe visual loss, since vi- sion remains normal in papilledema unless there is hemorrhage or exudate into the macula retinal area, which leads into rapid central visual loss – Optic chiasmal compression (central vision is served by the papillomacular bundle, which is more sensitive to external compression than the rest of the optic nerve fibers. The presence of optic atro- phy and bitemporal field defects are the clues to the diagnosis – Trauma (fracture of the anterior cranial fossa ex- tending into the optic foramen) – Amblyopia with papilledema (transient attacks as- sociated with raised intracranial pressure, e.g., benign intracranial hypertension) ESR: erythrocyte sedimentation rate. Neuro-Ophthalmology Tsementzis, Differential Diagnosis in Neurology and Neurosurgery © 2000 Thieme All rights reserved. Usage subject to terms and conditions of license. 101 Permanent blindness – Anoxia Infarction ț Sudden and marked impairment of the basilar artery flow, usually in elderly individuals ț Posttraumatic intracranial hypertension, leading to tentorial herniation and causing compression of the posterior cerebral arteries Hemorrhage E.g., traumatic, or rarely spontaneous – Multifocal metastatic tumors in the occipi- tal lobes – Multifocal primary tumors E.g., malignant gliomas – Multifocal abscess in the occipital lobes Optic neuropathy Ischemic neuropathy E.g., infarction of the anterior portion of the optic nerve due to systemic vascular disease or hypotension Traumatic neuropathy E.g., severe head trauma with indirect optic neu- ropathy from nerve swelling, tear, or hemorrhage Toxic nutritional neuro- pathy – Drugs E.g., barbiturates, streptomycin, chloramphenicol, isoniazid, sulfonamides – Alcohol E.g., methyl alcohol: overnight visual loss; tobacco and ethyl alcohol: progressive visual loss – Vitamin B 1 , B 12 , folic acid deficiencies Progressive visual loss over weeks Demyelinating neu- ropathy Binocular visual loss in more than 50% of children, whereas in adults it is usually monocular Retinal disease Retinal ischemia E.g., central retinal artery occlusion – Hemodynamic Usually with aortic arch syndrome, after a sudden change from the recumbent to the upright position in elderly individuals – Retinal migraine In one-third of cases in children and young adults – Coagulopathies E.g., increased platelet activity, and increased factor VIII – Miscellaneous risk factors E.g., congenital heart disease, sickle-cell disease, vasculitis, and pregnancy Blind trauma E.g., retinal contusion, tear, or detachment Trauma to carotid or vertebral arteries Symptoms develop over several hours, or sometimes days Pituitary apoplexy E.g., hemorrhagic infarction of the pituitary gland oc- curring usually in preexisting pituitary tumor Bilateral Sudden Visual Loss Tsementzis, Differential Diagnosis in Neurology and Neurosurgery © 2000 Thieme All rights reserved. Usage subject to terms and conditions of license. [...]... paranasal sinus infection, trauma or necrotizing otitis externa – Bacterial sinusitis From ethmoid or sphenoid sinuses, or intracranially via emissary veins and the cavernous sinus, resulting in cerebral infarction, meningitis, subdural empyema, and brain abscess – Fungal sinusitis Candidiasis, aspergillosis, histoplasmosis, rhinomucormycosis, resulting in multiple cranial nerve palsies, internal carotid... subject to terms and conditions of license Pineal Gland 115 Pineal Gland (Fig 6) Germ-cell tumors – Pure germinoma The most common variant of germ-cell neoplasm in this area, accounting for 50% of pineal neoplasms – Embryonal cell carcinoma – Choriocarcinoma – Teratoma – Mixed germ-cell tumor – Yolk sac tumor Endodermal sinus Pineal parenchymal (cell origin) tumors – Pineoblastoma – Pineocytoma Tumors... hypercoagulable states Clinically, there is a sudden severe visual loss, and funduscopy would show an opaque posterior retina and cherry-red macula, whereas the fovea and peripheral retina maintain a normal color Tsementzis, Differential Diagnosis in Neurology and Neurosurgery © 2000 Thieme All rights reserved Usage subject to terms and conditions of license 106 Neuro-Ophthalmology Central retinal vein occlusion... cells and is histologically similar to adrenal or sympathetic ganglionic neuroblastomas or retinoblastomas Tsementzis, Differential Diagnosis in Neurology and Neurosurgery © 2000 Thieme All rights reserved Usage subject to terms and conditions of license 1 24 Intracranial Tumors Tsementzis, Differential Diagnosis in Neurology and Neurosurgery © 2000 Thieme All rights reserved Usage subject to terms and. .. subject to terms and conditions of license 1 14 Intracranial Tumors Fig 6 Pineal lesions 1 Germinoma Sagittal T1 WI with a large, solid space-occupying lesion originating from the pineal gland and a high postcontrast signal intensity causing compression of the brain stem and cerebellum with distortion of the 4th ventricle.There is also descent of the cerebellar tonsils 2 Astrocytoma and suprasellar... sellae and laterally into the cavernous sinus – Meningioma Located alongside the sphenoid wing, diaphragma sellae, clivus, and cavernous sinus – Nerve sheath tumors ț Plexiform neurofi- Diffusely infiltrating masses originating primarily bromas along the ophthalmic and the maxillary and mandibular divisions of the trigeminal nerve ț Schwannomas Cause one-third of primary trigeminal nerve and Meckel’s cavity... appearing as bright white spots within the vascular tree, and originating almost exclusively from heart valves Tsementzis, Differential Diagnosis in Neurology and Neurosurgery © 2000 Thieme All rights reserved Usage subject to terms and conditions of license Transient Visual Loss 105 Other Rarer emboli include cardiac myxomas, fat (Purtscher’s retinopathy and pancreatitis), air, amniotic fluid, and particles... neuropathy head swelling, afferent pupillary reflex, decrease in color vision, altitudinal field defect – Foster–Kennedy syn- Optic atrophy in one eye and a swollen disk in the drome other, associated with anosmia Tsementzis, Differential Diagnosis in Neurology and Neurosurgery © 2000 Thieme All rights reserved Usage subject to terms and conditions of license 108 Neuro-Ophthalmology – Pseudo-Foster–Kennedy... cystic space-occupying, nonenhancing lesion in the right CP angle with compression signs of the pons 8 Epidermoid tumor A solid and heterogeneous mass with smooth margins eroding the left occipital bone and compressing the left cerebellar hemisphere is seen on axial T1 WI Tsementzis, Differential Diagnosis in Neurology and Neurosurgery © 2000 Thieme All rights reserved Usage subject to terms and conditions... of inflammatory tissue around the dens of C2 This pathology causes stenosis of the foramen magnum and compression of the spinal cord and lower medulla Focal myelinolysis is indicated by a high intensity signal Tsementzis, Differential Diagnosis in Neurology and Neurosurgery © 2000 Thieme All rights reserved Usage subject to terms and conditions of license Internal Auditory Meatus 121 Tsementzis, Differential . posterior retina and cherry-red mac- ula, whereas the fovea and peripheral retina maintain a normal color. Transient Visual Loss Tsementzis, Differential Diagnosis in Neurology and Neurosurgery. becomes involved rapidly, and the disease prog- resses within a few months to total blindness and fi- nally to death within a year Neuro-Ophthalmology Tsementzis, Differential Diagnosis in Neurology. hemorrhagic infarction of the pituitary gland oc- curring usually in preexisting pituitary tumor Bilateral Sudden Visual Loss Tsementzis, Differential Diagnosis in Neurology and Neurosurgery