scholarly journals Natural history of the anterior visual pathway after surgical decompression in patients with pituitary tumors

2015 ◽  
Vol 42 (S1) ◽  
pp. S45-S45 ◽  
Author(s):  
RA Won Hyung ◽  
W Chan ◽  
Y Starreveld ◽  
F Costello
Keyword(s):  
Structural Changes ◽  
Tumor Resection ◽  
Pituitary Tumors ◽  
Visual Pathway ◽  
Surgical Decompression ◽  
Fiber Layer ◽  
Nerve Fiber Layer Thickness ◽  
Compressive Neuropathy ◽  
History Of ◽  
Endoscopic Tumor Resection

Introduction: Visual dysfunction is one of the primary indications for surgical management of pituitary tumors with the goal of terminating the progressive decline in vision. Unfortunately, it is difficult to predict how successful surgical decompression will be in these patients. The purpose of this study was to assess the structural changes seen in the anterior visual pathway after pituitary tumor resection. Methods: 13 patients (7F) underwent endoscopic tumor resection for pituitary macroadenoma. Each patient underwent a full ophthalmologic assessment including optical coherence tomography (OCT) preoperatively and postoperatively at 3-6months and 9-12months. Post-surgical changes in the retinal nerve fiber layer thickness (RNFLT) for each eye (N=26) were compared in cases with normal preoperative RNFLT (greater than 80 μm) versus those with abnormally thinned RNFLT (less than 80 μm). Results: For 9 cases with thinned RNFLT preoperatively (mean=70.1 μm±8.5), there was a significant decline in RNFLT at 3-6 months follow-up (mean change= −3.8 μm;p=0.002), which did not recover even at 9-12months after surgery (mean=67.6 μm±12.7). Contrastingly, eyes with normal RNFLT preoperatively (mean=89.7 μm±9.4) did not show significant postoperative thinning (mean change= −1.9 μm). Conclusion: Even after a complete surgical decompression, there are ongoing structural changes in the anterior visual pathway in patients with compressive neuropathy. There may be a point of no return where surgical decompression may not prevent further structural degeneration.

scholarly journals MS optic neuritis-induced long-term structural changes within the visual pathway

2020 ◽  
Vol 7 (2) ◽  
pp. e665 ◽  
Author(s):  
Marc Pawlitzki ◽  
Marc Horbrügger ◽  
Kristian Loewe ◽  
Jörn Kaufmann ◽  
Roland Opfer ◽  
...  
Keyword(s):  
Optic Neuritis ◽  
Structural Damage ◽  
Structural Changes ◽  
Visual Pathway ◽  
System Structure ◽  
Pattern Reversal ◽  
Inner Plexiform Layer ◽  
Fiber Layer ◽  
History Of

BackgroundThe visual pathway is commonly involved in multiple sclerosis (MS), even in its early stages, including clinical episodes of optic neuritis (ON). The long-term structural damage within the visual compartment in patients with ON, however, is yet to be elucidated.ObjectiveOur aim was to characterize visual system structure abnormalities using MRI along with optical coherence tomography (OCT) and pattern-reversal visual evoked potentials (VEPs) depending on a single history of ON.MethodsTwenty-eight patients with clinically definitive MS, either with a history of a single ON (HON) or without such history and normal VEP findings (NON), were included. OCT measures comprised OCT-derived peripapillary retinal nerve fiber layer (RNFL) and macular ganglion cell/inner plexiform layer (GCIPL) thickness. Cortical and global gray and white matter, thalamic, and T2 lesion volumes were assessed using structural MRI. Diffusion-weighted MRI-derived measures included fractional anisotropy (FA), mean (MD), radial (RD), and axial (AD) diffusivity within the optic radiation (OR).ResultsMean (SD) duration after ON was 8.3 (3.7) years. Compared with the NON group, HON patients showed significant RNFL (p = 0.01) and GCIPL thinning (p = 0.002). OR FA (p = 0.014), MD (p = 0.005), RD (p = 0.007), and AD (p = 0.004) were altered compared with NON. Global gray and white as well as other regional gray matter structures did not differ between the 2 groups.ConclusionA single history of ON induces long-term structural damage within the retina and OR suggestive of both retrograde and anterograde neuroaxonal degeneration.

scholarly journals Evaluation of retinal nerve fiber layer thickness in patients of pituitary adenomas with and without optic chiasmal compression

2019 ◽  
Author(s):  
Kun Lei ◽  
Lina Wang ◽  
Meizi Wang ◽  
Shuran Wang ◽  
Yuanzhen Qu
Keyword(s):  
Nerve Fiber ◽  
Retinal Nerve Fiber Layer ◽  
Pituitary Tumors ◽  
Fiber Layer ◽  
Nerve Fiber Layer ◽  
Chiasmal Compression ◽  
Nerve Fiber Layer Thickness ◽  
Significant Difference ◽  
Sd Oct ◽  
Retinal Nerve Fiber

Abstract Background: Numerous studies have demonstrated loss of circumpapillary retinal nerve fiber layer (cpRNFL) thickness in patients with chiasmal compression using optical coherence tomography (OCT). This study aimed to evaluate the cpRNFL and ganglion cell compound (GCC) thicknesses in patients suffering pituitary tumors with and without chiasmal compression. Methods: forty-four patients with pituitary adenoma (PA) (twenty-one without chiasmal compression and twenty-three with chiasmal compression) and eighteen controls were enrolled. cpRNFL and GCC thickness were measured in both patients and controls by SD-OCT. Results: three groups (PAs with optic chiasmal compression, PAs without optic chiasmal compression and controls) were closely matched in terms of mean age, sex and IOP (p=0.173, p=0.184 and P=0.343, respectively). The average cpRNFL and GCC thickness was significantly different among three groups (cpRNFL : 94.1±12.5µm, 106.4±7.3µm, 110.7±6.9µm, respectively; GCC: 85.8±6.9µm, 93.8±5.0µm, 97.2±5.6µm, respectively ). The cpRNFL was analyzed in different regions, and significant difference was found in nasal upper and nasal lower between PAs without optic chiasmal compression and controls. Conclusion: Even there is no evidence of compression at the chiasm on magnetic resonance imaging (MRI), GCC and cpRNFL thinning could still be detected in patients of pituitary tumor by SD-OCT. The loss of RNFL is more severe in patients with chiasmal compression.

scholarly journals A Case of Merkel Cell Carcinoma of the External Auditory Canal Skin with Annulus and Tympanic Membrane

2021 ◽  
Vol 64 (7) ◽  
pp. 500-504
Author(s):  
Ara Cho ◽  
Mi Jang ◽  
In Seok Moon ◽  
Seung Ho Shin
Keyword(s):  
Cell Carcinoma ◽  
Merkel Cell Carcinoma ◽  
External Auditory Canal ◽  
Tumor Resection ◽  
Neuroendocrine Neoplasm ◽  
High Recurrence Rate ◽  
Adjuvant Radiation ◽  
Merkel Cell ◽  
History Of ◽  
Endoscopic Tumor Resection

Merkel cell carcinoma is an extremely rare neuroendocrine neoplasm of the external auditory canal (EAC) skin, which requires wide excision and adjuvant radiation due to a high recurrence rate. In this report, we describe a case of Merkel cell carcinoma arising from the EAC which was successfully treated with endoscopic excision. A 32-years-old female patient with a history of papillary thyroid cancer was diagnosed with an EAC tumor incidentally. There was a erythematous papular lesion on the posterior EAC without any evidence of locoregional metastasis. The patient underwent endoscopic tumor resection under general anesthesia, and the final pathologic report confirmed the diagnosis of Merkel cell carcinoma. There was no clinical or radiographic evidence of recurrence or metastasis of Merkel cell tumor for 41 months after surgical resection alone.

scholarly journals QUANTIFICATION OF RETINAL NERVE FIBER LAYER FOR EARLY DETECTION OF ANTERIOR VISUAL PATHWAY LESIONS

2021 ◽  
Vol 71 (1) ◽  
pp. 96-100
Author(s):  
Noureen Malik ◽  
Syed Abid hassan Naqvi ◽  
Zahra Arsalan
Keyword(s):  
Optical Coherence Tomography ◽  
Nerve Fiber ◽  
Layer Thickness ◽  
Retinal Nerve Fiber Layer ◽  
Visual Pathway ◽  
Fiber Layer ◽  
Nerve Fiber Layer ◽  
Nerve Fiber Layer Thickness ◽  
Significant Difference ◽  
Retinal Nerve Fiber

Objective: To assess the role of quantification of retinal nerve fiber layer for early detection of anterior visualpathway lesions. Study Design: Case-control study. Place and Duration of Study: Armed Forces Institute of Ophthalmology, Rawalpindi, from Jan to Jul 2019. Methodology: A total of 100 cases of anterior visual pathway lesions of varying clinical presentations wereincluded in the study. There were 100 matched controls who were selected from the community without anyophthalmological abnormality using non-probability consecutive sampling technique. Retinal nerve fiber layer(RNFL) thickness was measured with the help of optical coherence tomography in both the cases and controls.Mean retinal nerve fiber layer values were compared in both the groups. Student’s t-test was applied to look forany significant difference between the two groups. Results: Mean age of the patients was 39.14 ± 3.925 years while mean age of the controls was 39.23 ± 2.415 years. Mean retinal nerve fiber layer thickness in the case group was 72.21 ± 9.615 µm while on the control group was 101.34 ± 9.615 µm. A statistically significant difference was observed between cases and controls in terms of mean retinal nerve fiber layer thickness (p<0.001). Subjects with retinal nerve fiber layer thickness <85 µm were more likely to exhibit anterior visual pathway lesions (OR= 15.915 [6.278-40.346]; 95% CI, p<0.001). Conclusion: Decreased retinal nerve fiber layer thickness can serve as a predictor for anterior visual pathwaylesions. Optical coherence tomography should be incorporated for routine screening of high-risk cases in order to identify anterior visual pathway lesions in time.

scholarly journals Clinical features of toxic optic neuropathies

2017 ◽  
Vol 98 (3) ◽  
pp. 400-403
Author(s):  
N L Sheremet ◽  
N A Khanakova ◽  
N V Zhorzholadze ◽  
T A Nevinitsyna
Keyword(s):  
Optic Nerve ◽  
Optic Neuropathy ◽  
Structural Changes ◽  
Clinical Symptoms ◽  
Light Sensitivity ◽  
Ganglion Cell Complex ◽  
Fiber Layer ◽  
Chronic Alcohol Abuse ◽  
Nerve Fiber Layer Thickness ◽  
Toxic Optic Neuropathy

Aim. To study the features of the clinical symptoms of toxic optic neuropathy. Methods. 21 patients (42 eyes) with toxic optic neuropathy were examined with the use of standard ophthalmic exam, computer visual field test, spectral optical coherence tomography of the retina and optic nerve. Results. Toxic optic neuropathies were caused by the acute (4 patients) or chronic (10 patients) alcohol intake, drug abuse (6 patients) and medications (ethambutol, 1 patient). In all patients bilateral visual deterioration with central scotomas with various levels of light sensitivity reduction and prominent dyschromatopsia was revealed. The features of structural changes were reveled in patients with toxic optic neuropathy: the primary thinning of the retinal inner layers with further peripapillary retinal nerve fiber layer thickness loss. Severity of the structural changes ranged from the predominant damage of the retinal inner layers and minor decrease in the temporal peripapillary sector thickness to profound atrophy of the ganglion cell complex and optic nerve. In acute and chronic alcohol abuse after the treatment and complete alcohol cessation 43% of patients noted recovered visual function. Conclusion. Severity of the symptoms of toxic optic neuropathy, intensity and the rate of atrophy development, and prognosis depend on the nature of the toxin, its dose and exposure time, genetic features in each case; such algorithm of the changes is probably connected to the pathogenesis based on mitochondrial dysfunction.

scholarly journals A Rare Association between Myasthenia Gravis and a Growth Hormone Secreting Pituitary Macroadenoma: A Single Case Report

2019 ◽  
Vol 2019 (7) ◽  
Author(s):  
M T Farfouti ◽  
M Ghabally ◽  
G Roumieh ◽  
S Farou ◽  
M Shakkour
Keyword(s):  
Myasthenia Gravis ◽  
Single Case ◽  
Brain Mri ◽  
Tumor Resection ◽  
Pituitary Tumors ◽  
Pituitary Mass ◽  
Myasthenic Patient ◽  
Single Case Report ◽  
History Of ◽  
Underlying Causes

Abstract Myasthenia Gravis (MG) is a chronic autoimmune neuromuscular disease. Although it is well known that patients with myasthenia gravis have a higher incidence of other autoimmune disorders, however, its association with pituitary adenomas is extremely rare. We believe that our case represents the 8th of this association and the 2nd case involving a GH-secreting adenoma. Here we report a case of a 45-year old Syrian woman who presented with typical complaints of myasthenia gravis as she was suffering from variable painless and effort-related dysphagia and dysarthria. Her complaints became more evident at the end of the day, while acromegaly only manifested as a 4-month history of headache and a special facies that was noted by the physician. Brain MRI scan demonstrated a 3.21 x 2.42 x 2.35 cm pituitary mass for which the patient underwent a trans-sphenoidal pituitary tumor resection. In addition, postoperative histopathological investigations confirmed the diagnosis of a GH-secreting macroadenoma. On following up, it was observed that her myasthenic symptoms improved significantly on Pyridostigmin and Prednisolone. In conclusion, the presence of headache in a myasthenic patient should raise the attention for other underlying causes including pituitary tumors.

scholarly journals Linking Neural and Clinical Measures of Glaucoma with Diffusion Magnetic Resonance Imaging (dMRI)

2018 ◽  
Author(s):  
Nathaniel Miller ◽  
Yao Liu ◽  
Roman Krivochenitser ◽  
Bas Rokers
Keyword(s):  
Structural Changes ◽  
Structural Integrity ◽  
Anatomical Variation ◽  
Healthy Controls ◽  
Clinical Markers ◽  
Fiber Layer ◽  
Nerve Fiber Layer Thickness ◽  
Clinical Measures ◽  
Automated Methods ◽  
Cup To Disc Ratio

AbstractPurposeTo link optic nerve (ON) structural integrity to clinical markers of glaucoma using advanced, semi-automated diffusion weighted imaging (DWI) tractography methods in human glaucoma patients.MethodsWe characterized optic neuropathy in patients with unilateral advanced-stage glaucoma (n = 6) using probabilistic DWI tractography and compared their results to those in healthy controls (n=6).ResultsWe successfully identified the ONs of glaucoma patients based on DWI in all patients and confirmed that the degree of reduced structural integrity of the ONs determined using DWI correlated with clinical markers of glaucoma severity. Specifically, we found reduced fractional anisotropy (FA), a measure of structural integrity, in the ONs of eyes with advanced, as compared to mild, glaucoma (F(1,10) = 55.474, p < 0.0001). Furthermore, by comparing the ratios of ON FA in glaucoma patients to those of healthy controls (n = 6), we determined that this difference was beyond that expected from normal anatomical variation (F(1,9) = 20.276, p < 0. 005). Finally, we linked the DWI-measures of neural integrity to standard clinical glaucoma measures. ON vertical cup-to-disc ratio (vCD) predicted ON FA (F(1,10) = 11.061, p < 0.01, R2 = 0.66), retinal nerve fiber layer thickness (RNFL) predicted ON FA (F(1,10) = 11.477, p < 0.01, R2 = 0.63) and ON FA predicted perceptual deficits (visual field index [VFI]) (F(1,10) = 15.308, p < 0.005, R2 = 0.52).ConclusionWe provide semi-automated methods to detect glaucoma-related structural changes using DWI and confirm that they correlate with clinical measures of glaucoma.

scholarly journals IMPROVEMENT METHODS OF DIAGNOSIS THE VISUAL ANALYSER OF PATIENTS WITH MULTIPLE SCLEROSIS

2013 ◽  
Vol 12 (5) ◽  
pp. 76-86
Author(s):  
A. V. Kovalenko ◽  
G. N. Bisaga ◽  
E. V. Boiko ◽  
I. Yu. Kovalenko
Keyword(s):  
Multiple Sclerosis ◽  
Clinical Stage ◽  
Previous History ◽  
Automated Perimetry ◽  
Fiber Layer ◽  
Low Contrast ◽  
Neurodegenerative Process ◽  
Nerve Fiber Layer Thickness ◽  
History Of ◽  
Multiple Sclerosis Patients

137 (274 eyes) relapsing-remitting multiple sclerosis patients have been given detailed neuroophthalmologic examination. 58 of these patients (74 eyes) had a previous history of optic neuritis. As a result, the most informative methods of examination have been identified. These include the estimation of the frequency characteristics of the vision (vizokontrastoperimetriya, low-contrast tests Sloan), standard static automated perimetry, pattern visual evoked potentials, and optical coherence tomography which is used to measure macular volumes and retinal nerve fiber layer thickness. The above – mentioned methods make it possible to reveal the involvement of the optic analyzer in the inflammatory and neurodegenerative process at the pre-clinical stage. The obtained results allow us to recommend inclusion of the methods in the standard algorithm for the examination of patients with probable multiple sclerosis. 

The Reaction of Brain Structures with OsO4-Zinc-Iodide Stain

1971 ◽  
Vol 29 ◽  
pp. 272-273
Author(s):  
Werner J. Niklowitz
Keyword(s):  
Electron Microscope ◽  
Structural Changes ◽  
Mossy Fiber ◽  
Toxic Metal ◽  
Staining Technique ◽  
Brain Structures ◽  
Oxidase Inhibitor ◽  
Fiber Layer ◽  
Hippocampal Tissue ◽  
Zinc Iodide

After intoxication of rabbits with certain substances such as convulsant agents (3-acetylpyridine), centrally acting drugs (reserpine), or toxic metal compounds (tetraethyl lead) a significant observation by phase microscope is the loss of contrast of the hippocampal mossy fiber layer. It has been suggested that this alteration, as well as changes seen with the electron microscope in the hippocampal mossy fiber boutons, may be related to a loss of neurotransmitters. The purpose of these experiments was to apply the OsO4-zinc-iodide staining technique to the study of these structural changes since it has been suggested that OsO4-zinc-iodide stain reacts with neurotransmitters (acetylcholine, catecholamines).Domestic New Zealand rabbits (2.5 to 3 kg) were used. Hippocampal tissue was removed from normal and experimental animals treated with 3-acetylpyridine (antimetabolite of nicotinamide), reserpine (anti- hypertensive/tranquilizer), or iproniazid (antidepressant/monamine oxidase inhibitor). After fixation in glutaraldehyde hippocampal tissue was treated with OsO4-zinc-iodide stain and further processed for phase and electron microscope studies.

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