BConvergence

Downward Drifting The Arm

Internuclear ophthalmoplegia (INO), left side. a Paresis of adduction of the left and monocular nystagmus of the right eye on gaze to the right side. b Normal adduction during accommodative convergence, proving that the medial rectus itself is unaffected Dysarthria is a disturbance of the motor control of speech, resulting in poor articulation. In contradistinction to aphasia, which is categorized as a neuropsychological deficit (see above), dysarthria is a purely motor disturbance...

Frontolateral Approach

Frontotemporal Craniotomy

More recently, intraoperative stimulation of white matter tracts can be applied by using subcortical electrical stimulation to induce evoked potentials. When the patient is awake, even phosphenes can be induced using this technique. Whenever these responses are evoked during iterative stimulation, tumor resection has to be interrupted in order to preserve the functional integrity of the optic radiation ( Fig. 22.20). Fig. 22.17. Head positioning and skin incision for the frontolateral approach....

Info

Cat-scratch disease 115 cataract 9 catch trial 40 cavernous - - syndrome 151 cecocentral scotoma - differential diagnosis 45 central - areolar choroidal dystrophy (CACD) 241 - areolar pigment epithelial (CAPE) dystrophy 90 - vestibular nystagmus 167 cerebellar - disturbances of vision in children 257 cerebrospinal fluid (CSF) 220, 267 Cestan Raymond syndrome 147 CHAMPS (Controlled High Risk Subjects Avonex Multiple Sclerosis Prevention Study) 117 Charcot's triad 283 Charles Bonnet syndrome 190...

Scotoma Multiple Sclerosis

Myelinated Nerve Fiber Bundle Defect

Paramacular retinal choroidal process Artifactual displacement of a central scotoma by eccentric fixation at the scotoma's margin (with corresponding displacement of the physiologic (one that includes both the physiologic blind spot and the papillomacular bundle) Central areolar choroidal atrophy

Treatment of AAION

Treatment should be the immediate administration of a high dose of a corticosteroid. Prednisone is the most commonly used agent and should be given at doses of at least 1 mg kg of body weight daily. There is no uniform agreement as to the optimal dose of prednisone, but while doses of 30 to 50 mg day may be sufficient to relieve the general symptoms, they are inadequate for the protection of vision in the contralateral eye. There has been a trend toward the use of very high doses during the...

Severe Periodontitis After Radiotherapy

Optic Nerve Sheath Meningioma

Orbital tumors that are located lateral to the nerve may be resected via a lateral orbitotomy. Lesions superior to the optic nerve are removed using an orbitofrontal cra-niotomy. When the tumor is located below the nerve or medially, a transethmoidal or transmaxillary approach or a transconjunctival approach can be chosen. Optic nerve sheath meningeomas ( Fig. 22.1) may be treated with a variety of modalities, depending on the current visual status of the patient. If vision is lost completely,...

Optic Neuropathies of Malnutrition Definition

An optic neuropathy of malnutrition is one caused by a dietary deficiency. In the developed parts of the world, this is most commonly a deficiency of vitamin Bi2. Such cases are uncommon, and are most often caused by macrocytic anemia. Vitamin Bi2 and folate levels are easily measured. Other risk factors for malnutrition include intestinal bypass or gastric stapling for weight loss and the hepatic cirrhosis of alcoholism. Treatment should include intramuscular injections of high doses of...

Extensive Reading Definition

Aphasia Picture Description

Developmental dyslexia is an isolated disturbance of reading and writing in someone of normal intelligence and adequate schooling, with no accompanying deficits (whether sensory, motor, or psychological). The patient's history can yield valuable clues The problem has been present since the beginning of study of reading and writing. The parents report school problems, in particular poor grades in English, while the remaining subjects of school study are initially unaffected. Characteristically,...

Sensory Loss In One Side Of Body

Images Dissociated Sensory Loss

Apply tuning fork to surfaces with palpable subcutaneous bone (0-8 8) With eyes closed identify small objects placed in the hands Table 21.12. Additional pathologic signs symptoms of sensory systems Table 21.12. Additional pathologic signs symptoms of sensory systems Sensory perception is unpleasantly altered, e.g., touch is felt as pain Unpleasant sensations (itching, burning, formication) that are spontaneous, or elicited by gentle surface stimuli Sensations are amplified and are felt as...

Optic Neuropathy

If there is no suspicion of an arteritic process see below , a workup by the patient's internist or family physician should look for evidence of occult vascular disease. Aside from the usual risk factors hypertension, hypercholesterolemia, and diabetes mellitus , the physician should also look for an elevated hematocrit, signs of a vasculitic process, sleep apnea, or heart failure. The younger the patient, the more intensive this workup should be. Treatment in the acute phase of the...

Optic Tract No Macular Sparing

Optic Nerve Cancer

Homonymous hemianopsia to the left with good congruence no macular sparing causes severe loss of reading ability Retrochiasmal lesion in the contralateral hemisphere e.g., a tract lesion on the right side , or widespread damage to the retrogeniculate visual system on the right Vascular disease in about 75 of patients Infarction hemorrhagic or occlusive Arteriovenous malformation or aneurysm Space-occupying lesions in about 15 of patients Inflammation, e.g., multiple sclerosis Trauma up to 2 of...

Kfb Eye Procedure

Nystagmus predominantly in one eye in association with brainstem disease Most common form is that seen in internuclear ophthalmoplegia Physiologic, e.g., gazing out at passing landscape from a moving vehicle Can be tested with an optokinetic drum or tape, pathological asymmetry found with lesions of the temporoparietooccipital region Area 19 see Fig. 13.1

Neurosurgery of the Visual Pathway

Tatagiba The visual pathways take an extraordinary and extensive intraorbital and intracranial course from the globe to the visual cortex within the occipital lobes. Hence, a large number of orbital and intracranial pathologies interfere with the optic pathways. The diagnosis and treatment of these pathologies demands an interdisciplinary team with ophthalmologists, neuroradiologists, neurosurgeons, and radiation therapists. The management algorithm takes into...

Chiasmal Region of the Afferent Visual Pathway

Undisplaced Flap

The pathognomonic signs of chiasmal disease include bilateral, usually bitemporal, visual field defects that respect the vertical meridian see Chaps. 3 and 4 . The bitemporal character of the visual loss and typical course of isopters with sharply defined discontinuities at the midline are easily detected with kinetic perimetry in the central 30 of the field, but discrete defects are more accurately demonstrable by automated static perimetry. Fig. 12.2. Compression of the posterior pole with...

Where Is The Optic Nerve Located

Orbital Nerve Info

The transconjunctival approach is a useful way with good intraoperative visibility, especially for lesions located in the inferior medial and basal compartment of the orbit. Deep intraconal lesions at the orbital apex and extraconal superior lesions are less accessible by this approach. However, selected intraorbital lesions may be resected without muscle dissection, leading to excellent cosmetic and functional results. Fig. 22.14. Skin incision and bone removal for a lateral orbitotomy,...

Decompression Of The Optic Nerve Canal

Surgical Removal Hematoma

Optic nerve gliomas are often associated with neurofibromatosis type 1 and occur typically in the first decade of life Fig. 22.2 . Surgery has to be considered when loss of vision or radiological progression occur. In these cases, the nerve is resected with the tumor via a fronto-lateral approach to prevent chiasmatic involvement Fig. 22.3 . Cavernous hemangiomas are the most common benign primary orbital tumor of the adult and can be removed completely. The surgical approach depends on the...

Treatment of CN

In cases where the null point of nystagmus is eccentrically located, the compensatory head posture can be relieved through surgical repositioning of the null point to the primary position the Kestenbaum procedure . For many patients who experience dampening of the nystagmus during accommodative convergence, fusional vergence has a favorable effect. It can be tested by using base-out prism lenses in a trial frame to see whether fusional convergence is useable....

Ulnar Nerve Lesion Definition

Migration The Ulnar Nerve

Unilateral paresis of the tongue deviates to the healthy side in peripheral disease and caudal brainstem disease, less so with supranuclear disease cerebral lesions Fig. 21.2. Topographic summary of structures in the brainstem that are important for the localization of pathology cranial nerve nuclei and cranial nerves Roman numerals , the pyramidal tracts P volitional motor function , the posterior columns lemniscus medialis LM and their nuclei sensory afferents cerebellar tracts have been left...

Toxic Optic Neuropathies Definition

A toxic optic neuropathy is a bilateral optic neuropathy caused by the neurotoxic effects of medications usually chronic or environmental toxins acute or chronic . Ethambutol and other antitubercular drugs, cytostatic agents, heavy metals, hexachlorophene, and methanol can all cause a toxic optic neuropathy also see Chap. 17 . The first priority is to identify the offending agent and then to block further exposure. Specific measures that follow are determined by the nature of the toxin. The...

Temporal Bone Basal Cancer

Central fixation on an attractive stimulus, while introducing objects in the periphery, moving from unseeing to seeing An assistant introduces the object from the periphery, while the examiner carefully monitors the child's responses One finger, five fingers, fist, fixation in abductiona, monocular testing One, two, five fingers, or fist Monocular and binocular testing, altitudinal defects can also be discovered Look out for false constriction -test first with confrontation Reproducible...

Concentric Constriction

Concentric Constriction Visual Field

Such problems are usually unearthed during very careful history taking, and their discovery will generally lead to an appropriate plan for management. Reading Disorders Caused by Visual Field Defects Defects in the central visual field can limit the extrafoveal vision that is critical to the task of reading. This region, referred to as the reading visual field, gives a sufficient size of perceptive span to allow further scanning of the text in an organized fashion. Defects in this region of the...

How To Remove A Lesion In The Clinoid

Migration The Ulnar Nerve

Frontolateral or pterional craniotomies allow exposure and removal of these lesions with good functional outcome. Fig. 22.6. Meningioma of the left clinoid process in axial a and coronal b planes of contrast-enhanced T1-weighted MR images. Patient positioning and skin incision behind the hairline for a fron-tolateral approach to remove this lesion c Fig. 22.6. Meningioma of the left clinoid process in axial a and coronal b planes of contrast-enhanced T1-weighted MR images. Patient positioning...

Drug Induced and Toxic Disorders in Neuro Ophthalmology

Signal processing in the retinal photoreceptors, as well as in the cells and synapses of the afferent visual pathways, is controlled by a group of neurotransmitters, proteins, enzymes, and their metabolites that arise in complex cascades of chemical reactions to produce all the necessary functions of normal visual perception. Neurotropic drugs, toxins and some foods can interfere with these processes and their underlying structural components, thereby disturbing visual perception. In addition,...

Dural Carotid Cavernous Fistula

Dural carotid-cavernous fistulas arise spontaneously and primarily in elderly women. Dural branches of the internal or external carotid are equally involved, and fistulas often arise spontaneously from both sources. The resulting venous congestion causes an ectasia of the orbital and conjunctival veins that are clearly differentiable from inflammatory hyperemia large, rope-like conjunctival vessels that contrast with white scleral tissue , as well as chemosis with lid swelling, exophthalmos,...

Signs and Symptoms of Pituitary Tumors

The most common ophthalmological sign of a pituitary adenoma is the bitemporal loss of visual field see Chaps. 3 and 4 . Fundus findings are at most and often subtly optic disc pallor. A loss of visual acuity is not always present see above . Disturbances of motility involving dysfunction of the trochlear or abducens nerves are found in only about 10 of patients. With very large, eccentrically growing tumors, there is occasionally damage to the first two branches of the trigeminal nerve. ment....

Ductions and Versions

With the patient's head held in a fixed position, the examiner observes the limits of movement of each eye during visual pursuit of the examiner's hand finger into all diagnostic gaze positions. First, binocular movements are as- Fig. 10.2. Schematic diagram of motility deficits. The estimates of reduced motility are symbolized by minus signs for each of the diagnostic gaze positions adduction, abduction, and elevation and depression in abduction and adduction , and over actions are marked by...

B

B-scan echography 199 Babinski sign 280 bacterial sinusitis 134 Balint's syndrome 189 Barany's pointing test 283 Bardet-Biedl syndrome 90, 239 Bartonella henselae 115 Bassen-Kornzweig syndrome 234 Beh et's disease 94, 200 - syndrome 147 Bell's phenomenon 274 Benedikt's syndrome 143 benign - concentric annular macular dystrophy 90 - pediatric sixth nerve palsy 148 Bergmeister's papilla 107 Best's vitelliform macular dystrophy 89, 91, 98 beta-blocker 218 biceps tendon reflex 282 Bielschowsky...

Subarachnoid Damage to the Oculomotor Nerve

From the ventral midbrain, through the interpeduncular fossa and to its entry into the cavernous sinus, the third nerve lies in the subarachnoid space, where it is exposed to hemorrhages from aneurysms arising from the supracli-noid carotid artery, mostly at the exit of the posterior communicating artery. Rupture of such an aneurysm produces paralysis of the third nerve, but also the dramatic symptoms of acute subarachnoid bleeds, including abrupt headache of the worst sort, reduced levels of...

Treatment of Graves Disease

When managing the problems of active Graves' disease, the following measures are known to be of benefit maintenance of a euthyroid state, avoidance of cigarette smoking very important , use of topical hydrating agents with or without preservatives, as needed , and nonsteroidal anti-inflammatory drugs. These are largely supportive therapy, allowing time to pass and inflammatory activity to subside, while protecting vision in the meantime. This is adequate for a majority of cases. Infrequently,...

Supranuclear Disorders of Ocular Motility

There are several different types of eye movements coordinated with one another and regulated by an integrated control system. Refixation saccadic movements serve to redirect the eye, to bring images of interest to the center of the retina. Pursuit movements and optokinetic nystagmus prevent or reduce slippage of the image over the retina. The vestibulo-ocular reflex acts to stabilize the eye's position during head movements. Convergence and divergence movements allow objects at various...

S

Saccades, see also fast eye movement 157 sagittal sinus thrombosis 111 sarcoidosis 116, 200 sarcoma 181 scintillating scotoma 198, 218 scopolamine 66 scotoma 14, 21, 30 - with characteristic fundus changes 50 - scintillating 198 scotopization 15, 81 SDN, see sensory defect nystagmus sector- and wedge-shaped defect - differential diagnosis 45 sensory defect nystagmus - clinical testing 280 septic cavernous sinus thrombosis 134 serotonin agonist 218 severe head trauma 144 siderosis bulbi 94...

Intracavernous Carotid Aneurysm

An intracavernous aneurysm is extra dural, enlarges slowly, and constitutes an enlarging intracavernous mass, much like that of neoplastic, space-occupying lesions. Ruptures are not usual, but when they do open, a direct fistula is formed see above . Slow growth and frequent thrombosis, in contrast to supraclinoid aneurysms, have a generally good prognosis. Characteristic signs and symptoms include sixth nerve palsy, frequently with Horner's syndrome, facial pain first division of the fifth...

Treatment of Pituitary Tumors

For microadenomas, which cause no problem with vision, treatment is directed at relieving any hormonal imbalances. For macroadenomas with hormonal activity, medical therapy must usually be accompanied by some degree of surgical reduction in the size of the mass. Favorable effects can occur within 24 h of surgical decompression, after several days of medical management e.g., bromocriptine, see below , or several months after radiotherapy. The differential diagnosis of a pituitary adenoma should...

Q

- therapy 301 radioperiosteal reflex 282 radiosurgery 302 RAPD, see relative afferent pupillary defect Rayleigh equation 76, 77 RBON, see retrobulbar optic neuritis reading 303 - sensory disturbances 304 rebound movement 283 red-green dyschromatopsia 15 refixation saccades 160 reflex - scotoma, with characteristic fundus changes 50 refractive ametropia 8 refractometer 5 Refsum's disease 234 relative afferent pupillary defect RAPD 10, 12, 24, 30, 58, 59, 114, 124, 176, 208 relative scotoma 39...

How To Heal Eyes Naturally Tilted Optic Nerve Drusen

Optic Nerver Glioma

The differential diagnosis of optic atrophy in children Fig. 19.6. a Lesion of the right optic tract with an incongruous, homonymous quadrantic hemianopia to the left. Optic discs The disc of the right eye has temporal pallor with a shallow excavation, while the disc of the left eye has a bow-tie pattern of pallor, evident in both the nasal and temporal disc quadrants. This finding is easily missed, when a direct ophthalmoscope is not used. b Visual field testing static perimetry...

Brain Tumors Relevant to Clinical Neuro Ophthalmology

The ophthalmologist should keep in mind that the differential diagnosis always includes the chance that a brain tumor might be at fault. It is not at all unusual for these potentially life-threatening diseases to present with purely ophthalmologic symptoms. Bitemporal or anterior junction defects MRI only when a tumor is still suspected MRI of the orbits MRI of the orbits alternatively CT and the chiasmal region Bitemporal or anterior junction defects Papilledema from any location of tumor...

Radiation Optic Neuropathy Definition

Optic Neuropathy Radiation

Radiation optic neuropathy is a consequence of highdose radiation therapy delivered to the region of optic nerve and or chiasm, which often presents abruptly in a manner that mimics acute retrobulbar optic neuritis. The loss of vision is usually profound and there is no effective therapy to reverse the process, once it has begun. An interval of 9 to 12 months or more after radiation therapy is the usual temporal sequence, and the optic disc is initially normal in appearance hence the similarity...

T Pearl

Feathered Nerves Optic Nerve Head

Macropapilla is easily confused with advanced glauco-matous cupping, but is easy to distinguish from glaucoma by demonstrating the presence of a normal visual field. In discs with very large cups that appear to be pathological, one should carefully examine the neuroretinal rim - that ring of tissue that surrounds the physiologic cup and covers the surface of the disc to its very margin. The examiner should take note of the color of the neuroretinal tissue is it a healthy pink or is it pale,...

D

Line Bisection Test

Acuity Swinging flashlight test Anterior segment Fundus Diagnosing visual loss of uncertain origin - see Chap. 2 Homonymous visual field defects or normal Nonphysiological only with justified suspicion j _ Simulation tests The where system occipitoparietal Disorders of visual orientation Flow diagram. Diagnostic procedures in the case of suspected central disturbances of vision The how or what system occipitotemporal Cerebral achromatopsia Table 13.1. Summary of commonly described symptoms in...

Clinoid and Sphenoid Wing Meningiomas

Twenty-five percent of all meningiomas arise near the anterior clinoid processes or along the sphenoid wings. Most affected are women 66 aged 30 to 50 years. Exophthalmos is caused in 50 of cases, and optic disc swelling occurs often bilaterally in half of all meningiomas of this category. Growth through the superior orbital fissure and into the orbit is common, and is usually associated with prominent hyperostosis of the sphenoid wing, as seen on CT scans. Typical visual field findings include...

Aicardi Syndrome Retina

Spasmus Nutans Symptoms

Circumpapillary chorioretinal lacunae in a young girl. The disease is lethal in males. b Aicardi syndrome. Hypoplasia of the corpus callosum arrow and cortical heterotopia Proper diagnostic classification of congenital or neonatal nystagmus is challenging. A practical schema is illustrated in the flow diagram of Fig. 19.11 see also Chap. 11 . Sensory defect nystagmus SDN , or ocular nystagmus that arises from a congenital defect in retinal and or optic nerve...

Crossing Isopters In Functional Visual Loss

Visual Acuity Testing Documentation

ERG electroretinogram, VEP visually evoked potentials, OKN optokinetic nystagmus 206 ERG electroretinogram, VEP visually evoked potentials, OKN optokinetic nystagmus 206 Observations of Behavior and Triggering of Reflexes For those complaining of complete blindness, behavioral observation provides telling information. When greeted for the first time, does the patient reach for your hand, bump into obstacles, or have trouble finding the examination chair On passage down a flight of stairs, those...

Optic Neuritis In Diabetes

Neuritis Cat Scratch Disease

High-dose corticosteroids or no therapy Surgical decompression, radiation, or no intervention Benign tumors, visual recovery possible Fig. 8.15. At the acute onset of optic neuritis the optic disc can appear completely normal left or swollen Pain on eye movement is very characteristic of optic neuritis and is reported by more than 90 of affected patients. Fig. 8.15. At the acute onset of optic neuritis the optic disc can appear completely normal left or swollen 3. Age in a majority of cases, 18...

Headache from a Neuro Ophthalmic Point of View

Tension Headache Diagram

Headache is the most frequent cause for cooperative interaction between neurologists and ophthalmologists. Frequently, patients are seen first by their primary care physicians, and are then referred to ophthalmologists for further testing and management, chiefly to rule out ocular sources of pain. From there, they are commonly referred to neurologists, to be sure that something serious will not be missed. The diagnostic classification of headache is at first glance extraordinarily confusing or...

Hereditary Disorders of Neuro Ophthalmic Relevance

Alport Syndrome Sign And Symptoms

Hereditary disorders of importance for neuro-ophthalmology include genetically inherited disorders of the posterior segment and afferent visual pathway that characteristically present as visual field defects, visual acuity loss, strabismus, or even complete blindness. These disorders have significant social and economic importance with lifelong consequences for the afflicted patient. The prevalence of inherited retinal disorders is approximately 20 cases per 100,000 people. Decoding of the...

Optic Atrophy after Papilledema Definition

Damage to the optic nerve caused by chronic papillede-ma. If elevated intracranial pressure goes undetected, bilateral loss of vision can develop, because chronic papilledema often leads to gliosis and atrophy of the optic nerve. The same problem can develop if the cause of the elevated pressure cannot be corrected. The pathogenic mechanism is not well understood, but ischemia is thought to play an important role. The time needed to develop this complication is variable and is not predictable...

Traumatic Optic Neuropathy Definition

A traumatic optic neuropathy is one caused by trauma to the optic nerve, most frequently in the setting of a traffic accident with cranial and or midface fractures. Traumatic optic neuropathy results primarily from indirect injury, rather than by direct crushing or tearing mechanisms. A direct blow to the eye can cause an avulsion of the optic nerve more properly called an expulsion . The mechanism appears to be one of a sudden, explosive increase in intraocular pressure with rupture of the...

Functional Visual Loss and Malingering

Ophthalmic Differential Diagnosis Tables

Malingering is an intentionally deceptive mimicry of a nonexistent disorder, and augmentation is an intentionally exaggerated account of an existing disorder. Functional visual loss is a subjectively described visual disorder without an objectively observed abnormality. It is an unconscious, often subconscious, simulation of a nonexistent disease. Synonyms include psychogenic visual loss, conversion, and hysterical visual loss . The related group of psychogenic ocular disorders includes...

Choroid Feather Appearance

Optic Disc Hypoplasia Double Ring

The association of myelinated nerve fibers with cutaneous nevi is known as Gorlin's syndrome, and also as basal cell nevus syndrome, which needs to be identified early in life, so as to minimize the risk of developing cutaneous melanomas. Melanocytomas of the optic disc are benign and require only regular follow-up examinations. They are strikingly black in color, prominent, and commonly extend across the margin of the disc or are surrounded by a choroidal nevus. The have a soft, feather-like...

Symptom Of Pelopsia

Allesthesia

Schematic diagram of the most common pseudo hallucinations. Upside down inverted objects. Macropsia microp-sia objects seen as too large or small. Telopsia pelopsia objects seen as too far or near. Palinopsia objects seen in correct relation to others e.g., exclusively situated on horizontal planes and thus in multiple locations a subtype of polyopsia . Metamorphopsia objects misshapen. Polyopsia multiple images of a single object a failure of the extinguishing center . Platyopsia...

Signs and Symptoms of the Arteritic Form of AION j Note

Giant Cell Arteritis

It is particularly important to consider the possibility that an acute case of ischemic optic neuropathy might be arteritic in nature, for if the problem is indeed caused by arteritis, it should be considered as an emergent situation requiring immediate intervention with highdose corticosteroid therapy. The average age at the onset of anterior ischemic optic neuropathy in patients with temporal arteritis AAION is about 75 years. Arteritis can also present with branch retinal vessel occlusions,...

Ophthalmoplegic Migraine

A small number of migraine patients experience an ipsilat-eral oculomotor paresis in connection with an episode of migraine. Like the migraine attacks, this form of paresis appears during childhood as the initiating event in an episode that includes vomiting, photophobia, abdominal pain, irritability, and less commonly headache. The paresis affects all branches and recovers completely, as a rule, within a month's time. Relapses can repeatedly occur, sometimes after years of inactivity, and such...

Subnormal Photoreceptor Functions

Electroretinogram

Multiple evanescent white dot syndrome MEWDS Normal or reduced b-wave and oscillatory potentials The EOG is the testing method of choice when the primary damage is thought to lie in the retinal pigment epithelium. The most important indications for the EOG are a suspicion of Best's vitelliform macular dystrophy and the suspicion of a pigment epitheliopathy, especially when assessing visual function during chronic chloroquine therapy. The phototransduction process in the photoreceptor outer...

Friedemann Kimmich Neuroophthalmology

Yet another textbook of clinical neuro-ophthalmology This text and its digital supplement are meant to be used by comprehensive ophthalmologists and residents in training, and are not meant to be used as one would the larger, almost encyclopedic, reference texts with their detailed citations and case reports. Resident physicians should find the format of this text particularly helpful as a learning tool, including the interactive, digital DVD supplement. The material is sufficiently complete as...

Afferent Pupillary Defect

Efferent Pupillary Defect

Axons by way of the third cranial nerve to the ipsilateral ciliary ganglion from where postganglionic parasympathetic fibers innervate the eye via the short posterior ciliary nerves, terminating at the pupillary sphincter. This anatomically bilateral sharing of neural input has the important consequence that damage to the afferent visual pathways that lead to the Edinger-Westphal nucleus cannot cause an anisocoria. Thus, anisocoria is never a sign of an afferent disturbance, but is always a...

Fundus Albipunctatus Treatment

Mferg Stargardt Disease

For macular diseases, however, the multifocal ERG see below is a particularly valuable diagnostic test. During the flash ERG, the following values are recorded The amplitude of the a-wave, measured from the electrical baseline to the negative peak recorded just before the appearance of the b-wave The amplitude of the b-wave, measured from the valley of the a-wave to the positive peak of the b-wave The implicit times, meaning the time from the flash stimulus to the peak of the corresponding ERG...

Pituitary Apoplexy

Pituitary Apoplexy

Only 30 of patients presenting with pituitary tumors complain of visual problems. The tumor must rise more than 1 cm above the diaphragma sellae before causing a clinically detectable loss of visual field and or acuity. Commonly, this is a hormonally inactive tumor that due to the absence of endocrine signs or symptoms has been very inconspicuous. Pituitary microadenomas are those with a diameter of 10 mm or less. The threshold for radiological detection of a microadenoma is 3 mm or less. A...

Segment of the Afferent Visual Pathway

Optociliary

Tumors of the prechiasmal segment of the afferent visual pathway are typically unilateral and for that reason often unnoticed , cause a fluctuating acuity deficit from day to day, and have a slow rate of progression. Monocular visual deficits that vary with the direction of gaze are frequently a sign of a retrobulbar mass, such as a hemangioma or an optic nerve sheath meningioma. Frequently an associated loss of color saturation, especially for red colors, also escapes the patient's notice....

Signs and Symptoms of Nonarteritic Anterior Ischemic Optic Neuropathy

The average age of patients with acute nonarteritic anterior ischemic optic neuropathy NAION is about 61 years. The visual loss occurs abruptly and without a prodromal warning, usually while the patient is asleep or within a 12-h period, and there is no associated pain or headache. The initial swelling of the optic disc subsides within 2 months, leaving a pale, atrophic appearance, which is often sectoral most commonly located in the superior half of the disc . There is for the most part no or...

Of Neuro Ophthalmic Emergencies

Ninety percent of clinical neuro-ophthalmology is in the taking of a history after W.F. Hoyt . Attentive listening, specific questioning and careful evaluation of the information gained make up the foundation of what is primarily a diagnostic subspecialty. The effort invested in gathering this information saves time and avoids unnecessary, potentially dangerous and or expensive diagnostic procedures. When possible, the previous records of the patient's care should be reviewed prior to beginning...

J Note

Optic Nerve Edema

Typical cases of recurrent retrobulbar optic neuritis RBON should not be treated with lower doses of orally administered medication, since this is known to double the risk of subsequent relapses of demyelination. In the 1990s, the use of beta-interferon and copolymer 1 proved effective at reducing both the frequency and severity of attacks of demyelination in patients with clinically definite MS meaning two or more separate episodes of demyelination . Another study reported in the year 2000...

Swinging Flashlight Test

Swinging Flashlight Test

When an Optical Disturbance Is Found If the Snellen acuity can be improved by a reduced aperture device or if there are visible irregularities in the media often best seen in the reflected light of the fundus reflex through a dilated pupil , there should be a systematic search for any or all of the following causes. A repetition of the subjective and objective refractions with pupillary dilation and cycloplegia is necessary. This will occasionally uncover an undetected or an irregular corneal...

Optic Disc Signs and Optic Neuropathies

The fundoscopic examination of the optic disc affords the physician one of the very few practical and completely patient-independent, objective neuro-ophthalmic signs. Techniques and Criteria for Assessment of the Optic Disc In the papilla of the optic nerve i.e., that part that is visible to the physician - having a diameter of about 1.5 mm about 1.3 million ganglion cell axons and their associated glial support cells crowd through the limited scleral opening at the lamina cribrosa to form the...

Differential Diagnosis of Trochlear Nerve Pareses

In many cases of superior oblique paresis, it is not the trochlear nerve at fault, but it is instead caused by changes in the trochlear tendon complex or the body of the muscle itself. These patients have a marked overaction of the antagonist inferior oblique in adduction, a positive Biel-schowsky head-tilt test, an amazing amplitude of the vertical fusional vergence movements able in some cases to fuse a hyperphoria of 40 prism diopters , and a long standing history of head tilt to...

Neuro Ophthalmic Aspects of Orbital Disease

Right Orbit Structures

Orbital diseases are distinct from primary ocular disorders in that they require consideration of a much larger group of differential diagnoses. Thus, ptosis may be attributable to a simple problem in the anterior segment, but may also be the clinical presentation of a more general disorder, such as Horner's syndrome, oculomotor paralysis, or myasthenia gravis. One must also consider orbital involvement in primary disorders of the periorbital structures, including the paranasal sinuses and the...

Hypothalamus Nuclei

Hypothalamic Nuclei

The extent of optic atrophy does not correlate with the extent of acuity loss. Even bilateral optic atrophy does not always rule out a possible recovery of both Snellen acuity and visual field. However, disc pallor does suggest that the recoverability of optic nerve and chiasmal function after surgical decompression is limited. Development of papilledema caused by chiasmal perichi-asmal disease is very uncommon but does occur when the mass compresses and obstructs the foramina of Monro. This...

Clinical Presentation

Pituitary Gland Carotid Artery

The signs and symptoms depend on the speed at which the pathological process progresses. Abrupt expansion of the intrasellar contents, after infarction or hemorrhage into a pituitary adenoma, causes a rapid onset of combined, often bilateral cranial neuropathies, associated with severe headache and uni- or bilateral, often profound, loss of vision. With a subarachnoid hemorrhage, the patient's condition can rapidly deteriorate to the level of a coma. Neuroradio-logical imaging will show an...

Internuclear Opthalmoplegia

Internuclear Ophthalmoplegia

MLF lesion left internuclear ophthalmoplegia -MLF lesion and PPRF lesion and or N. VI lesion right one-and-a-half-syndrome MLF lesion left internuclear ophthalmoplegia -MLF lesion and PPRF lesion and or N. VI lesion right one-and-a-half-syndrome Fig. 11.5. a,b Supranuclear and nuclear structures of the ocular motor system. View of the translucent brainstem from behind. The impulse for right gaze is generated in the right PPRF. The signal is transmitted to the right abducens nucleus VI . There,...

Electrophysiology

Optic Tract

Electrophysiological methods of examination involve the recording of bioelectric potentials that arise during the neural processing of visual information by the various elements of the afferent visual pathways. Changes in the various types of electrical potentials allow conclusions to be made about the locations and kinds of functional disturbances in the afferent neurons of the visual system. The examination methods of electrophysiology, including the electroocu-logram EOG , the various types...

Clinical Features of Graves Disease

Conjunctival Injection Graves

Graves' disease also called thyroid ophthalmopathy, dys-thyroid ophthalmopathy, or endocrine orbitopathy is an autoimmune disease that commonly, though not always, is associated with hyperthyroidism. It is accompanied by a broad spectrum of signs and symptoms of orbital inflammation. Chief among these is exophthalmos. Graves' disease is the most common cause of exophthalmos among Fig. 9.5. A patient with Graves' disease. Striking proptosis, left more than right, with bilateral retraction of...

Ocular Tilt Reaction

Ocular Tilt Reaction

A unilateral interruption of the otolithic afferent pathway causes the ocular tilt reaction OTR , which has four components 1. A yoked rotational displacement of both eyes around the visual axis 2. A vertical strabismus skew deviation 4. A tilt of the subjective visual perception of the vertical All four components are tilted in the same direction. In the example diagrammed in Fig. 11.8, the tilt is to the right. The rotational displacement of both eyes and the skew deviation are caused by an...

Opthalmic Nerve

Ciliary Ganglion Ophthalmic Nerve

Schematic overview of the anatomy of the pupillary light reflex arc. By way of the optic tract the afferent path of the pupillary system projects to the dorsal midbrain pretectum, 2 . From there, the signal is carried to the Edinger-Westphal subnucleus in the nuclear complex of the oculomotor third cranial nerve. The oculomotor nerve innervates the ciliary ganglion 3 , from which the short posterior ciliary nerves arise and enter the eye to innervate the pupillary sphincter 4 . Not to...

Chemosis

Congenital Ptosis

Chemosis is associated with a variety of usually benign disease processes in the anterior segment, but can also be typical of a group of orbital disorders orbital inflammatory diseases, such as idiopathic inflammatory pseudotumor, ocular myositis, dysthyroid ophthalmopathy, or any impairment of venous outflow from the orbit e.g., carotid-cavernous fistula or infiltrating orbital malignancies . Table 9.3 summarizes the various diagnostic methods used for the study of orbital disease. A rational...

Optic Tract Lesion

Visual Field Loss Optic Atrophy

Structures of neuro-ophthalmic relevance and their relative positions in the perichiasmal region modified from von Lanz et al. 2003 see Further Reading The relative positions of chiasm and hypophysis means, on the one hand, that microadenomas by definition as intra-sellar lesions never cause perimetrically detectable visual field defects. On the other hand, when an adenoma has grown so large that it is detectable by the visual field defect it causes, it is already at an advanced stage...

Dyschromatopsias Associated with Neuro Ophthalmic Disease

Lanthony Desaturated

Krastel, and W. Hart People with congenital dyschromatopsias are frequently not aware that their color perception differs from those with normal, trichromatic color vision. Others have learned to adapt to their limited perception of certain colors. Thus, a person with faulty red green color discrimination will often describe a dark green color as red. Some of these people know that they cannot properly identify colors accurately in certain ranges of hue and luminance....

Wilbrand S Knee

Mri Varix Knee

Nonetheless, perimetry remains a very important diagnostic tool for following the course of disease in this region. The very thin fibers of the papillomacular bundle are clustered together in the core of the optic nerve, and they represent the largest number of fibers in the so-called par-vocellular system. These axons project into the layers of the lateral geniculate body that contain neuronal somas, which are also quite small see Fig. 3.6 . Parvocellular neurons transmit the encoded image...

To the Optic Tract

Bow Tie Atrophy Optic

Optic atrophy after damage to the optic tract is a characteristically bilateral, though asymmetric, form of optic atrophy that develops in patients with chronic lesions of the optic tract. Lesions affecting this last portion of the third neuron see Chap. 3 produce a characteristic pattern of optic atrophy that is ophthalmoscopically manifest within several weeks or months after the damage also see Chap. 19 . Corresponding to the course of the nerve fibers, the atrophy in the disc ipsilateral to...

Fascicular Abducens Palsies

Medial Longitudinal Fasciculus

The anatomic neighbors of the paramedian pontine reticular formation the PPRF, also the center for horizontal gaze control include the facial nerve, the uncrossed pyramidal tracts, the sensory and sympathetic long tracts, and the abducens nerve Fig. 10.7 . The clustered proximity of these structures and the long intrapontine course of the sixth cranial nerve make collateral damage very common for fascicular lesions of the abducens nerve Table 10.3 . The classical brainstem syndromes described...

Temporal Crescent

Temporal Crescent

Fatigue, poor concentration, cannot understand the task of divided attention Compressive optic neuropathy see Chap. 8 Loss of nasal nerve fibers in glaucoma or optic disc drusen see Chap. 8 Bilateral retrogeniculate damage to the posterior visual pathways see Chaps. 3 and 12 Tests of functional disorders, exaggeration and or malingering see Chap. 15 When indicated MRI, CT, lab testing Artifact lens rim, lens holder. Check the centering of the perimeter lens Be sure to use an age-matched...

Oculomotor Apraxia Definition

Apraxia Definition

Oculomotor apraxia describes an eye movement disorder characterized by loss of or severely diminished volitional saccades with retention of the fast phases of vestibular nystagmus. Reflexive saccades stimulated by objects of interest in the peripheral visual field may be disordered or normal. Congenital oculomotor apraxia Cogan's syndrome manifests in newborn infants. During the first 3 months of life, affected infants are unable to look toward objects held out to them, and may be mistakenly...

Spasm of the Near Reflex

Spasms of accommodation and convergence are usually functional in nature, but are occasionally the result of a severe head injury or part of a dorsal midbrain syndrome. A highly variable moment-to-moment esotropia is accompanied by pupillary miosis and accommodative myopia. When binocular horizontal pursuit movements are tested, the adducting eye takes up fixation in either direction. This pseudo-abducens palsy is usually enhanced during cover uncover testing Fig. 10.8 . The spasms can last for...

Clinical Findings

Oculomotor Paralysis

Total loss of function in the third cranial nerve produces paralysis of the levator palpebrae superioris, with complete ptosis of the upper lid. The sympathetically innervated smooth muscle of the upper lid Muller's muscle can shorten the levator aponeurosis but will not cause any opening of the palpebral fissure. With passive elevation of the upper lid, the examiner will find the eye resting in an abducted position of 20 to 30 . Attempts at adduction in fresh cases will produce a weak movement...

Signs and Symptoms of Compressive Optic Neuropathy

The optic disc in an eye with a compressive neuropathy can be normal, swollen, or atrophic. The appearance depends on the timing, location, and duration of the compression. Atrophy of the disc signs of pallor and loss of nerve fiber bundle striations indicates that there has already been some permanent damage to the optic nerve, and a full recovery of function will not be possible. A swollen optic disc indicates that the site of compression is in or near the orbital apex. Orbital masses...

Infranuclear Disorders of Ocular Motility

Infranuclear disorders of ocular motility are marked by abnormal eye movements caused by lesions below the level of the cranial nerve nuclei. These lesions include damage to the cranial nerves, the extraocular muscles, or the connective tissue of the orbit. Their origins range from relatively harmless disorders to severe diseases that are life threatening. Infranuclear disorders produce paretic and or mechanical strabismus with severe deficits of visual perception by means of diplopia image...

Optic Nerve Carotid Artery

Ciliospinal Center Budge

If the affected pupil dilates as well or better than its contralateral partner, the site of damage lies somewhere below the level of the ganglion cervicale superius, i.e., in the first- or second-order neurons of the sympathetic pathway. Lower concentrations of phenylephrine about 2 are well suited to the pharmacologic detection of weakened pupillary dilators. Among infants, one often finds an aniso-coria with normal pupillary light reactions and no ptosis that persists after instillation of...

Perimetry

Visual Field Confrontation

Hart Examination of the visual field, whether on a hemispheric surface in which case one is doing perimetry or on a flat surface where one is doing campimetry is perhaps the single most important diagnostic test in neuro-ophthalmology. By visual field we mean the sum total of all visual sensation experienced by on observer with a fixed head and torso position, with eyes steadily gazing at a stationary object. This is in contradistinction to field of view and...

Collateral Vessels Retina

What Are The Appearances Papilledema

5 g The pathogenesis of papilledema is not one of leakage of a c fluid into the interstitial spaces of the optic disc. It is actually caused by intrinsic swelling of the ganglion cell axons because of stasis of axoplasmic flow in the prelaminar optic nerve see Chap. 3, Fig. 3.3 . This explains why atrophic optic discs cannot swell when intracranial pressure is elevated. If the disc swelling is present in one eye only, it still could be papilledema. Well-documented cases of unilateral...

Bruckner Test Strabismus

Ckner Test

Ammann test no further deterioration of acuity when viewing the chart through a neutral density filter an amblyopic eye behaves as if it is already dark-adapted Pathological Ammann test, i.e., there is further deterioration of acuity when viewing the chart through a neutral density filter the patient with an injury or an episode of inflammatory activity plausibly associates the cause of the poor vision. In all likelihood, the event was only a cause for drawing attention to the eye and discovery...

Of the Human Visual Pathway

Arrangement Fibres Optic Nerve

Nearly a half of all cortical neurons are devoted to the processing of visual information. The afferent visual pathway from the retina to the primary visual cortex has four neuronal elements Fig. 3.1 . First neuron photoreceptors Second neuron bipolar cells Third neuron retinal ganglion cells and their axonal processes, including the chiasm and optic tracts Fourth neuron geniculocalcarine neurons Surface area of the cerebral retina is about 30 cm2 Fig. 3.1. Schematic diagram of the human visual...