Where is the lesion of a junctional scotoma? Although numerous automated perimetries are available, the Humphrey strategies, in particular, the Swedish Interactive Thresholding Algorithm (SITA) standard and SITA fast programs, are the most commonly used. 4. A recorded number of 0 indicates that the patient could not detect even the brightest stimulus at that point. [1] [2] Ophthalmologic findings typically involve visual field defects (e.g., optic neuropathy, junctional visual loss, bitemporal hemianopsia), although less commonly patients may also have efferent complaints (e.g., ocular motility deficits from cavernous sinus involvement, Nystagmus ). Bromocriptine is the first-line agent used in treating prolactinomas and suppresses prolactin secretion by binding to D2 dopamine receptors. Cushing syndrome describes the assortment of physiologic changes that occurs with elevated serum cortisol levels. [6], Pituitary "incidentalomas" are lesions of any kind found in the pituitary on imaging performed for a different purpose. 3.7). Characterization of the visual field defect often allows precise localization of the lesion along the visual pathways. Instruct the patient to count fingers presented within the central 30 degrees (in each of four quadrants around fixation). - hypothyroidism . Lesions of the optic radiations typically produce a contralateral homonymous hemianopia, worse superiorly when the lesion is in the temporal lobe and worse inferiorly when the lesion is in the parietal lobe. Lesion groups 1 and 2 result in a bowtie pattern of optic atrophy (Fig. In addition to the visual field defects, there may be decreased visual acuity, which is always the same in both eyes (Fig. What values indicate an unreliable Humphrey Visual Field? If it is homonymous, is the defect complete or incomplete? 11. Dept of Ophthal & Optometry,AKH, Medical University of Wien Dept of Ophthal & Optometry,AKH, Wien, Austria, Department of Ophthalmology, Goethe University of Frankfurt am Main Department of Ophthalmology, Frankfurt am Main, Germany, 2015 Springer-Verlag Berlin Heidelberg (outside the USA), Khan, K., Almarzouqi, S.J., Morgan, M.L., Lee, A.G. (2015). A right homonymous hemianopia (contralateral to lesion). Upper Altitudinal Hemianopia is caused as a result of destruction of bilateral destruction of lingual gyri. Natural history of nonfunctioning pituitary adenomas and incidentalomas: a systematic review and metaanalysis. Lesion group 3 results in mostly temporal atrophy of the left optic nerve (Fig. Ophthalmology is typically consulted to evaluate the patient's visual fields. 1. A large number of fixation losses (>33% of false-positive or false-negative responses) indicates an unreliable test. 3.31). The nasal visual field falls on the temporal retina. Types of Field Defects Merck and the Merck Manuals Merck & Co., Inc., Kenilworth, NJ, USA is a global healthcare leader working to help the world be well. Junctional scotoma, Bitemporal defects, Homonymous hemianopia defects (w/wo macular sparing, spared temporal crescent). Rarely juxtaposed homonymous quadrantanopic or hemianopic visual field defects can mimic bilateral altitudinal visual field loss. What disease can cause this? 3.10 indicates the amount each point deviates from the age-adjusted normal values. It contains input from the superior retinal quadrants, which represent the inferior visual field quadrants. 2. Signs that you may have a visual field defect include: Bumping into things Knocking over objects when reaching Having difficulty reading Getting into a car accident A central scotoma in the eye ipsilateral to the lesion & a superotemporal defect in the fellow eye. What field defects results from ischemia limited to of the tip of an occipital lobe? At the level of the chiasm, the crossing inferonasal fibers travel anteriorly toward the contralateral optic nerve before passing into the optic tract. This is called Wilbrands knee and is responsible for the junctional scotoma in lesions of the posterior optic nerve. If it respects the vertical meridian, is the defect bitemporal or homonymous? They tend to be macroadenomas at time of clinical diagnosis due to the subtle manifestations of excess growth hormone. Adapted from Bagheri N, Duraani AK: The Wills Eye Manual, ed. Figure 1. What values indicate an unreliable Humphrey Visual Field? A comparative scale on the bottom relates the degree of grayness on the gray scale to the change in decibel levels from the numeric grid. The most common cause of this type of nerve fiber layer visual field defect in adults is glaucoma, but any process that damages the retinal nerve fiber layer can produce an altitudinal visual field defect including retinal vascular damage (e.g., branch retinal artery occlusion), nonarteritic and arteritic anterior ischemic optic neuropathy, optic disk drusen, papilledema, and other lesions producing optic nerve damage. Nonfunctioning adenomas are less likely to enter remission following surgical treatment than functioning adenomas. 12. "Tumors of the Pituitary Gland." Nelson syndrome does not occur as often now that neuroimaging techniques are better and more easily available.[5]. 3.19, Fig. If the middle cerebral artery is patent when the PCA is occluded, this focal area of the occipital lobe may be spared. The temporal crescent syndrome. Symptoms include night blindness and loss read more ), nonphysiologic vision loss, Rare: Bilateral occipital disease, tumor or aneurysm compressing both optic nerves, Loss of all or part of the lateral half of both visual fields; does not cross the vertical median, More common: Chiasmal lesion (eg, pituitary adenoma, meningioma, craniopharyngioma, aneurysm, glioma), Enlargement of the normal blind spot at the optic nerve head, Papilledema, optic nerve drusen, optic nerve coloboma, myelinated nerve fibers at the optic disk, drugs, myopic disk with a crescent, A loss of visual function in the middle of the visual field, Macular disease, optic neuropathy (eg, ischemic Ischemic Optic Neuropathy Ischemic optic neuropathy is infarction of the optic disk. These tumors are the most common causeof optic chiasm compression in adults. If it is homonymous, is the defect complete or incomplete? For further information, please see the additional resources section at the end of this article. 1. 3.4.1 Anterior Visual Pathways Currently, there is no effective treatment to reverse the visual impairment in NAION. 13. It is a defect surrounded by normal visual field. Optic neuropathies typically produce nerve fiber bundle defects within the central 30 degrees of the visual field. Fixation Loss 20% [1][2] Ophthalmologic findings typically involve visual field defects (e.g., optic neuropathy, junctional visual loss, bitemporal hemianopsia), although less commonly patients may also have efferent complaints (e.g., ocular motility deficits from cavernous sinus involvement, Nystagmus). The optic nerve in altitudinal visual field loss may show sector or diffuse edema, be normal, or show optic atrophy. Patients will often complain that they have trouble with anteroposterior tasks such as cutting fingernails, threading needles, and working with precision tools. 2003. [2][6] Overall, it is estimated that in upwards of 25% of the population have pituitary adenomas although most of these are incidentally found. 3.21 show different homonymous hemianopias. Retrochiasmal lesions normally cause homonymous visual field defects; the only exception is the temporal crescent or half moon syndrome, caused by a lesion in the anterior part of the contralateral parieto-occipital sulcus. 3. [39] Endoscopic techniques have improved visualization of the tumor and allowed for smaller incisions and faster healing. This may be: central (e.g. If it respects the vertical meridian, is the defect bitemporal (temporal side of the vertical meridian in each eye) or homonymous (on the same side of the vertical meridian in each eye)? A patient with altitudinal visual loss is more likely to have a carotid or cardiac embolic source compared with patients with diffuse or constricting patterns of vision loss. Pearls The stimulus size is kept the same, but the brightness varies. Ask the patient to signal detection of the white dot by pressing a buzzer. Is the test normal? Ali K. Pract Neurol 2015;15:5355 Lesions of the optic tract cause a contralateral homonymous hemianopia, which may or may not be congruent. Sudden expansion of the pituitary mass into the cavernous sinus can cause sudden ophthalmoplegia and facial hypoesthesia due to compression of cranial nerves III, IV, V, and VI, with cranial nerve III being affected most commonly. 4. In optometry, ophthalmology, and neurology, a visual . For example, a small detachment in the inferior retina results in a small superior visual field defect, while a large temporal detachment causes extensive nasal field loss. She later presented with right-sided visual disturbance; her examination confirmed temporal crescent syndrome. H53.439 is a billable ICD-10 code used to specify a medical diagnosis of sector or arcuate defects, unspecified eye. What are the monocular VF defect patterns? Goldmann visual field showing a bitemporal hemianopsia. LH deficiency is manifested by decreased energy and libido in men due to decreased testosterone levels, and amenorrhea in premenopausal women. 3. By varying the distance of the patient from the screen, it is possible to differentiate organic from nonorganic constriction of the visual field: in organic patients, the visual field enlarges when the patient is placed farther away from the screen (see Chapter 18). 3 Visual Fields So all three of these visual fields are examples of field defects where there is some respect to the horizontal midline. The lesion may be anywhere along the optic pathway; retina to occipital cortex. A comparative scale on the bottom relates the degree of grayness on the gray scale to the change in decibel levels from the numeric grid. 2. multiple endocrine neoplasia (MEN) type 1, https://doi.org/10.1007/s12022-017-9498-z, https://eyewiki.org/w/index.php?title=Pituitary_Adenoma&oldid=88579, Some multiple hormones, others are nonsecreting, Aneurysms (internal carotid artery, middle or anterior cerebral artery, or anterior communicating artery), Patients with prolactinomas who cannot tolerate the side effects from dopaminergic agonist therapy, Patients with prolactinomas who had no tumor shrinkage with dopaminergic agonist therapy, Patients with prolactinomas who decided on primary surgical excision, Patients with prolactinomas who had cystic features on MRI (80% of tumor volume on T2 sequences) that were unlikely to shrink sufficiently with medical management alone, Patients with cavernous sinus involvement, Patients with vision-related symptoms from compression of the optic apparatus. It appears in people with damage to one hemisphere of their visual cortex, and occurs simultaneously with bilateral homonymous hemianopia or homonymous quadrantanopia. Supported by Ask the patient to count fingers in two quadrants simultaneously. Patients with pituitary adenomas have a variable history, dependent on the functional (secretory) status of the tumor, its size, and any mass effect. 3.26). Place the patients head on a chin rest in front of a computer screen. Prechiasmal damage to the visual pathway usually involves the optic nerve (e.g., optic neuritis , optic atrophy, AION , papilledema Most patients show improvement of visual acuity, visual fields, or both following surgical treatment. 2. While a majority of patients with endogenous Cushing syndrome have thyrotrophic adenomas (called Cushing Disease - see below), other tumors should also be considered as part of the endocrinologic workup, including adrenal tumors and especially ACTH-secreting small cell carcinoma of the lung. Central, Cecocentral, Paracentral, Arcuate/Sector, Nasal Step, Altitudinal, Enlarged blind spots, Temporal Crescent Defect. Hypercortisolism is not present because of the absence of the adrenal glands. What are the bilateral VF defect patterns? The WHO currently recommends against using the term atypical adenoma as there is no accurate prognosis 12. Thieme Macular lesions produce central or paracentral defects, whereas most degenerative retinopathies, such as retinitis pigmentosa, produce progressive constriction of the peripheral and midperipheral visual field (Fig. 2. 2. A homonymous hemianopsia denser inferiorly (opposite of pie in the sky). What field defect results when a stroke only affects the anterior portion of the occipital lobe? Altitudinal defects occur in retinal vascular disease, glaucoma, and other disorders that affect the eye itself. 3.11): 5. [6] These tumors tend to be large and invade adjoining structures, which can cause visual field defects. 5. It is the technique of choice for patients with optic nerve lesions, papilledema, chiasmal compressive lesions, and other progressive visual disorders. The stimulus size is kept the same, but the brightness varies. It can be arteritic or nonarteritic. IRT. 3.3 Interpretation of a Visual Field Defect, 3.3.1 Understanding a Humphrey Visual Field Printout. [5] Vison loss due to compression first affects the superotemporal visual fields, then inferotemporal, inferonasal and finally superonasal fields. If it is homonymous and incomplete, is the defect congruent (same defect shape and size in each eye)? 3.30). These axons are destined for the lateral geniculate nucleus, where they synapse with neurons whose axons then form the optic radiations. Lesions of the parietal lobe often impair optokinetic nystagmus (see Fig. [49] It was found that recurrence rates can be decreased with a combination treatment of surgery and radiotherapy (from 7-35% to 7-13%). In: Miller NR, Newman NJ, eds. Vision tends to return to normal or almost normal without treatment in a couple [24], Pituitary adenomas that compress on the chiasm can often produce a slow decrease in visual function. The patient sits 1m from a black screen (mounted on a wall) on which there are concentric circles. Patients undergoing radiation therapy tend to have a slower recovery and time to improvement.[5]. Most ACTH-secreting pituitary adenomas are small, with detection of the tumor earlier due to the significant systemic changes. The test involves the following steps: Automated static perimetry or kinetic perimetry are used to formally assess visual fields. Adenoma cells stain on immunohistochemistry based on the type of hormone they secrete. Gonadotrophic adenomas secrete lutenizing hormone (LH) and follicle-stimulating hormone (FSH). 3.13). The numeric grid just to the right of the measurements of reliability is a presentation of the threshold level in decibels for all points checked in the patients visual field. The far periphery can be assessed by finger wiggle. Bilateral homonymous hemianopias Pain is often unilateral, throbbing, worse with exertion, and accompanied by symptoms read more (which may cause transient homonymous hemianopia). Treatment for the nonarteritic read more or Leber hereditary neuropathy Leber hereditary optic neuropathy Hereditary optic neuropathies result from genetic defects that cause vision loss and occasionally cardiac or neurologic abnormalities. The incidence of pituitary adenomas presenting as monocular visual field defects was reported to be 9% (in a series of 1,000 patients). 3.22b) of the right optic nerve. Optic Tract While the patient is asked to fixate on a central target, a white or colored circular stimulus is slowly moved from the periphery toward the center of the screen until the patient reports seeing the stimulus. Learn more about the Merck Manuals and our commitment to Global Medical Knowledge. 7. Bilateral occipital lobe lesions will produce bilateral homonymous hemianopias, which may be asymmetric (Fig. The nasal visual field falls on the temporal retina. A congruent visual field defect presents with the same exact shape in the field of both eyes. [1] Periodic neuroimaging is also essential, as recurrence may occur even as late as 10 years post-surgery. Visual field testing is useful when evaluating patients complaining of visual loss (especially when the cause of visual loss is not obvious after ophthalmic examination) or patients with neurologic disorders that may affect the intracranial visual pathways (e.g., pituitary tumors, strokes involving the posterior circulation, and traumatic brain Patients with secretory tumors may have systemic complaints that are associated with their corresponding hormonal imbalance. The visual field and retina have an inverted and reversed relationship. Crooke cell adenomas, another subset of corticotroph adenomas, have characteristic morphology on immunohistology stains with a ring of LMWK and PAS positive granules along the periphery. The slow-growing nature of these tumors tends to cause optic atrophy before the tumor enlarges sufficiently to compress the third ventricle or produce sufficient mass effect to increase intracranial pressure (ICP). My Education Find an Ophthalmologist Home Coronavirus For Ophthalmologists Meetings AAO 2022 Meeting Information Past and Future Meetings Mobile Meeting Guide Contact Information 3.10), which provides a gross picture of the size and severity of the field defects present. Special attention should be directed to the horizontal and vertical axes of the visual field to see if there is a change in vision across an axis. These numbers are then converted to a gray scale representation of the field (upper right, Fig. On T2-weighted images, the adenoma is more indistinct, as it appears isointense or only slightly hyperintense in comparison with the surrounding gland. 3.10, the left eye was tested (as indicated by the word left in the upper right corner). Springer, Berlin, Heidelberg. Lights of different sizes and brightness allow the drawing of isopters. Thieme, 2. The upper division (Figure 17-2) projects to the upper bank of the calcarine sulcus, the cuneus. Microincidentalomas (<1 cm) have been reported to be more common than macroincidentalomas (4-20% vs. 0.2% on CT, 10-38% vs. 0.16% on MRI, respectively). 3.13). Uncorrected refractive errors or disturbances in the normally clear media (such as cataract) cause a general loss of sensitivity of the visual field. Complete homonymous hemianopias may occur with any lesion of the retrochiasmal visual pathways and do not allow precise localization of the lesion along the retrochiasmal visual pathways. Bowtie atrophy of the right optic nerve Depending on the etiology of the optic neuropathy, arcuate defects, altitudinal defects, and central, paracentral, or centrocecal scotomas are observed (Fig. 3.27). The physiologic blind spot corresponds to the optic disc (which has no overlying photoreceptors) and is located approximately 15 degrees temporally in each eye. Or simply, visual field can be defined as the entire area that can be seen when an eye is fixed straight at a point. Zhang X, Horwitz GA, Heaney AP, Nakashima M, Prezant TR, Bronstein MD, Melmed S. Pituitary tumor transforming gene (PTTG) expression in pituitary adenomas. It is characterized by the presentation of acute, severe headache, nausea, and altered consciousness. Hemifield slide diplopia from altitudinal visual field defects. 1.27) when stimuli are moved in the direction of the damaged parietal lobe (Fig. Reddy R, Cudlip S, Byrne JV, Karavitaki N, Wass JA. 2. This corresponds to superior, bitemporal, and central vision loss. Grid: Present a square grid of lines and ask the patient to fixate on a central point and to draw any area in which the lines disappear (Fig. Fideleff HL, Boquete HR, Surez MG, Azaretzky M. Prolactinoma in children and adolescents. Testing strategies for visual fields are discussed below. Present stimuli consisting of dots of white light projected one at a time onto the inner surface of the bowl, usually moving from the unseen periphery into the patients field of view. At present, What are the findings of bilateral occipital lobe lesions? The densely granulated variant is more common and is usually basophilic, and the sparsely granulated variant is chromophobic. Most improvement takes place between 1-4 months. Although the anatomical presence of Wilbrands knee is debated, junctional scotomas are observed clinically. The resulting manifestations of the disease process include peripheral field loss, which may progress to central vision loss and legal blindness without intervention in the advanced disease state. 3.23). The altitudinal defect can be unilateral or bilateral. An unusual presentation of optic neuritis and the Pulfrich phenomenon. 8. [25] When a filter is placed in front of one eye and a moving object at a constant distance away is viewed, the person perceives the object as having depth, when in reality it is moving in the same plane. Some patients with complete bitemporal hemianopsia will complain of a complete loss of depth perception. 2. This disease classically affects older patients with vasculopathic risk factors and sleep apnea. visual field loss indicates a prechiasmal pathology, while bilateral visual field loss indicates a chiasmal or retrochiasmal pathology. "Tumors of the Pituitary Gland." The normal visual field in each eye is approximately (Fig. Pituitary adenomas are a collection of tumors that arise from the pituitary gland. 3.22b). 10. 2. PubMed Central When we fixate with both eyes, there is superimposition of the central 60 degrees of visual fields in both eyes. The rule of congruency states that the more congruent the homonymous hemianopia, the more posterior the lesion. The test involves the following steps: 8. The most common cause is a retinal break (a tear or, less commonly, a hole) (rhegmatogenous read more, Less common: Glaucoma Overview of Glaucoma Glaucomas are a group of eye disorders characterized by progressive optic nerve damage in which an important part is a relative increase in intraocular pressure (IOP) that can lead to irreversible read more , optic nerve lesion, optic nerve coloboma, A small, bow-shaped (arcuate) visual field defect that follows the arcuate pattern of the retinal nerve fibers; does not cross the horizontal median, Damage to ganglion cells that feed into a particular part of the optic nerve head, More common: Glaucoma Overview of Glaucoma Glaucomas are a group of eye disorders characterized by progressive optic nerve damage in which an important part is a relative increase in intraocular pressure (IOP) that can lead to irreversible read more, Less common: Ischemic optic neuropathy Ischemic Optic Neuropathy Ischemic optic neuropathy is infarction of the optic disk. Special attention should be directed to the horizontal and vertical axes of the visual field to see if there is a change in vision across an axis. Therefore, chronic optic tract lesions will cause optic atrophy, often in a characteristic pattern. 2. It can be repeated to monitor if the defects are growing or shrinking as a measure of whether the disease process is worsening or improving. 1. [3] One review found an average incidence of 16.7% (14.4% in autopsy studies and 22.5% in radiologic studies). Guaraldi F, Salvatori R. Cushing syndrome: maybe not so uncommon of an endocrine disease. [6] The term, pituitary carcinoma is reserved forcases with metastatic spread, either local or systemic invasion, and comprise of <1% of tumors. Postsynaptic fibers from the lateral geniculate nucleus form the optic radiations, which separate into the inferior fibers (temporal lobe) and the superior fibers (parietal lobe) as they progress posteriorly toward the occipital cortex (Fig. [2][24], As described above, extraocular muscle paresis is a rare presentation (~5% of patients with pituitary adenoma) most often associated with a concurrent palsy of the corresponding cranial nerve. Because of the anatomy of the posterior ciliary arteries, optic nerve ischemia often results in a superior (more often) or inferior segmental optic nerve atrophy. The Academy uses cookies to analyze performance and provide relevant personalized content to users of our website. [4], Papilledema is a rare finding in pituitary adenomas. The nasal visual field extends to 60% of the horizon, whereas the temporal fieldextends to a further 3040 beyond that; this part of the visual field is represented on the contralateral anterior parieto-occipital sulcus. Patients can have decreased consciousness or strokes from extravasation of blood into the subarachnoid space. Of all conditions causing the chiasmal syndrome, pituitary adenomas are the most common (50-55%). more or Leber hereditary neuropathy Leber hereditary optic neuropathy Hereditary optic neuropathies result from genetic defects that cause vision loss and occasionally cardiac or neurologic abnormalities . Distinction of densely vs sparsely granulated adenomas is mainly through low molecular weight cytokeratin (LMWK) immunohistochemistry. 3. It can quickly establish the pattern of visual field loss in the ill, poorly attentive, or elderly patient who requires continued encouragement to maintain fixation and respond appropriately. o [teenager OR adolescent ], Loss of all or part of the superior or inferior half of the visual field; does not cross the horizontal median, More common: Ischemic optic neuropathy, hemicentral retinal artery occlusion Central Retinal Artery Occlusion and Branch Retinal Artery Occlusion Central retinal artery occlusion occurs when the central retinal artery becomes blocked, usually due to an embolus. The equivalent concept for optical instruments and image sensors is the field of view (FOV).. Bone window scans help assess erosions and extensions into the sphenoid sinus. What are the bilateral VF defect patterns? 3.3). Visual field defects seen in each eye's visual field and the image perceived by the patient: a) right HH; b) left HH; c) left HH with macular sparing; d) right superior quadrantanopia, 'pie in the sky'; e) inferior quadrantanopia 'pie on the floor' Figure 2. 3.9). Two cases of generalised visual-field loss are presented, binocular loss in a girl with LCA and monocular loss in a boy with optic nerve hypoplasia. They make up 30-50% of pituitary adenomas and are the most common clinically functional adenomas. Bilateral occipital lobe lesions will produce bilateral homonymous hemianopias, which may be asymmetric (Fig. There is pallor affecting only the superior or inferior half of the optic nerve. 3. 1. The diplopia is binocular (only present when both eyes are open), and can have horizontal, vertical, or torsional components depending on the affected cranial nerve(s). It uses a threshold strategy, in which the stimulus intensity varies and is presented multiple times at each location so that the level of detection of the dimmest stimulus is determined. 4. 5. A junctional scotoma. (This rule does not apply to optic tract lesions that are suspected when the homonymous hemianopia is associated with a RAPD on the side of the hemianopia and bilateral optic nerve pallor). High Prevalence of Pituitary Adenomas: A Cross-Sectional Study in the Province of Liege, Belgium. In addition to the visual field defects, there may be decreased visual acuity, which is always the same in both eyes (Fig. Visual Field Defects Symptoms Vision loss in one eye may indicate a problem in the eye, whereas the same visual field defect in both eyes may signal a problem in the brain. Having a high basal hormonal level postoperatively was predictive of recurrence in functional adenomas, but there are no known predictive factors for recurrence in nonfunctioning adenomas. The test involves the following steps: The ability of the patient to perform the test can be evaluated by measurements of reliability reported on the printout. double vision. A contralateral homonymous hemianopia that is small and centrally located. This page was last edited on January 17, 2023, at 09:56. A variety of retinal or more central pathologies can cause visual field deficits that are limited to particular regions of visual space. Retrochiasmal lesions normally cause homonymous visual field defects; the only exception is the temporal crescent or half moon syndrome, caused by a lesion in the anterior part of the contralateral parieto-occipital sulcus. (C) Worsening optic disc swelling right eye (OD) with onset of vision loss OD; left optic nerve has superior pallor. [3] Most prolactinomas are sparsely granulated; on histology these tumor cells are weakly acidophilic or chromophobic. Less commonly, ophthalmologists may be the first to detect evidence of a pituitary adenoma. What are the bilateral VF defect patterns? An altitudinal visual field defect is a condition in which there is defect in the superior or inferior portion of the visual field that respects the horizontal midline. 10. If binocular, does the defect respect the vertical meridian? 11. PubMedGoogle Scholar. 4. Altitudinal defect ##### 4) Arcuate scotoma ##### 5) Paracentral scotoma . Relative to the point of fixation: 14. [18] Acidophil stem cell adenomas (ASCA) additionally have elevated GH and IGF-1. Presenting Visual Symptom of Chiasmal Compression. Pituitary or sella sequence magnetic resonance imaging (MRI) with and without contrast is the study of choice for most sellar and parasellar lesions, but high-resolution CTs with fine cuts (1.5-3 mm) have also been shown to be very helpful in the differential diagnosis especially if calcification is seen (e.g., craniopharyngioma or meningioma).