Surgical Outcomes of Standardized Endoscopical Deep Medial Orbital Decompression in Dysthyroid Optic Neuropathy.

INTRODUCTION: The aim of the study was to standardize the endoscopic deep medial orbital decompression surgery for better relief of optic nerve compression in dysthyroid optic neuropathy (DON). METHODS: A total of 128 eyes from patients received the standardized endoscopic deep medial orbital decompression surgery were recruited in this study. The efficacy of the procedure was assessed at a 1-month follow-up by the best-corrected visual acuity (VA), visual field (VF), and visual evoked potential (VEP). Clinical data were collected to explore the factors that affected visual recovery. Oxygen saturation of retinal blood vessels, retinal thickness, and vessel density were measured to demonstrate the potential recovery mechanisms. RESULTS: After surgery, the ratio of extraocular muscle volume in the orbital apex to orbital apex volume significantly decreased from 44.32 ± 22.31% to 36.82 ± 12.02% (p < 0.001). 96.87% of eyes' final VA improved; average VA improved from 0.93 ± 0.73 to 0.50 ± 0.60 at 1 week (p < 0.001) and 0.40 ± 0.53 at 1 month (p < 0.001). Postoperatively, VF and VEP also improved, the oxygen saturation of retinal arteries increased, and the retinal thickness was reduced. Preoperative VA, visual impairment duration, and clinical activity score evaluation were associated with visual recovery. CONCLUSION: In this study, we standardized the endoscopic deep medial orbital decompression, of which key point was to relieve pressure in the orbital apex and achieved satisfactory visual recovery in DON patients.

Case of infiltrative optic neuropathy with hypertrophic pachymeningitis as a manifestation of en plaque meningioma.

We describe a case of infiltrative optic neuropathy with hypertrophic pachymeningitis noted on MRI of the brain, presenting a diagnostic dilemma with a wide variety of differential diagnoses to consider. Our patient is a middle-aged woman with a 20-year history of migranous-sounding headaches who was incidentally found to have worsening vision in her left eye during a routine driving test visual acuity check. Neurological examination revealed a left grade III relative afferent pupillary defect and a central scotoma with red desaturation. Subsequent MRI of her brain and anterior visual pathway revealed features suggestive of an infiltrative left optic neuropathy with hypertrophic pachymeningitis. An extended workup including diagnostic lumbar puncture and blood tests for possible autoimmune, infective and neoplastic causes proved unyielding. Eventually, an endoscopic transsphenoidal biopsy helped to clinch the diagnosis of a (meningothelial subtype) WHO grade 1 meningioma as the cause of her clinical and radiological presentation.

Neuro-ophthalmic Complications in Pediatric Leukemia.

BACKGROUND: Optic neuropathy in childhood leukemia occurs through multiple direct and indirect mechanisms, including leukemic infiltration of the optic nerve, infection, blood dyscrasias, or adverse effects of treatment. We aimed to characterize visual outcomes in pediatric patients with leukemia-associated neuro-ophthalmic manifestations. METHODS: We retrospectively identified patients with leukemia and optic nerve pathology over 13 years by diagnostic billing codes. We collected information on demographics, presentation, treatment course, and visual outcomes directly from medical records. RESULTS: Of the 19 patients who met inclusion criteria, 17 (89.5%) had pseudotumor cerebri and 2 had direct optic nerve infiltration. Causes of increased intracranial pressure included central nervous system infiltration (6 of 17), hyperviscosity/leukemia (2 of 17), venous sinus thrombosis (3 of 17), medication induced (5 of 17), and bacterial meningitis (1 of 17). 47.1% (8 of 17) had papilledema at the time of leukemia diagnosis, and 94.1% (16 of 17) of patients with pseudotumor cerebri were treated with acetazolamide. At presentation, 3 patients had decreased vision secondary to macular ischemia, subhyaloid vitreous hemorrhage, or steroid induced glaucoma. Following treatment of pseudotumor cerebri, binocular visual acuity was ≥20/25 in all patients. One patient with optic nerve infiltration had a final visual acuity of count fingers in the affected eye. CONCLUSIONS: In our chart review, the most common mechanism of neuro-ophthalmic involvement in pediatric leukemia was elevated intracranial pressure from a myriad of causes. Visual outcomes from patients with elevated intracranial pressure were excellent. Understanding the mechanisms by which leukemia can cause optic nerve disease in pediatric patients can facilitate earlier diagnosis and treatment and potentially improve visual outcomes.

Ischemic optic neuropathy as first presentation in patient with m.3243 A > G MELAS classic mutation.

BACKGROUND: Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome is a systemic disorder in which multi-organ dysfunction may occur from mitochondrial metabolism failure. Maternally inherited mutations in the MT-TL1 gene are the most frequent causes for this disorder. Clinical manifestations may include stroke-like episodes, epilepsy, dementia, headache and myopathy. Among these, acute visual failure, usually in association with cortical blindness, can occur because of stroke-like episodes affecting the occipital cortex or the visual pathways. Vision loss due to optic neuropathy is otherwise considered a typical manifestation of other mitochondrial diseases such as Leber hereditary optic neuropathy (LHON). CASE PRESENTATION: Here we describe a 55-year-old woman, sister of a previously described patient with MELAS harbouring the m.3243A > G (p.0, MT-TL1) mutation, with otherwise unremarkable medical history, that presented with subacute, painful visual impairment of one eye, accompanied by proximal muscular pain and headache. Over the next weeks, she developed severe and progressive vision loss limited to one eye. Ocular examination confirmed unilateral swelling of the optic nerve head; fluorescein angiography showed segmental perfusion delay in the optic disc and papillary leakage. Neuroimaging, blood and CSF examination and temporal artery biopsy ruled out neuroinflammatory disorders and giant cell arteritis (GCA). Mitochondrial sequencing analysis confirmed the m.3243A > G transition, and excluded the three most common LHON mutations, as well as the m.3376G > A LHON/MELAS overlap syndrome mutation. Based on the constellation of clinical symptoms and signs presented in our patient, including the muscular involvement, and the results of the investigations, the diagnosis of optic neuropathy as a stroke-like event affecting the optic disc was performed. L-arginine and ubidecarenone therapies were started with the aim to improve stroke-like episode symptoms and prevention. The visual defect remained stable with no further progression or outbreak of new symptoms. CONCLUSIONS: Atypical clinical presentations must be always considered in mitochondrial disorders, even in well-described phenotypes and when mutational load in peripheral tissue is low. Mitotic segregation of mitochondrial DNA (mtDNA) does not allow to know the exact degree of heteroplasmy existent within different tissue, such as retina and optic nerve. Important therapeutic implications arise from a correct diagnosis of atypical presentation of mitochondrial disorders.

CT analysis of predictors for visual acuity in optic neuropathy with mucocele.

OBJECTIVE: To evaluate the causative and risk factors for optic neuropathy with mucocele via imaging studies. METHODS: We included 21 patients with rhinogenous optic neuropathy with mucocele. We collected data on the sinus involved, age, sex, number of days from the onset of visual impairment to surgery, and computed tomography (CT) imaging findings (bone defects in the lamina papyracea, Onodi cell mucocele, exophthalmos, and optic nerve deviation). The results were compared between two groups, the one having nine patients with pre-operative visual acuity of <0.1 (the poor group) and the other having 12 patients with pre-operative visual acuity of ≥0.1 (the fair group). Whether or not there was a difference in pre-operative visual acuity between patients with and without Onodi cell mucocele was determined. RESULTS: After surgery, visual acuity improved in 16/21 (76.2%) patients, and a correlation analysis showed a significant positive correlation between pre-operative and post-operative visual acuity. In imaging, the causative sinuses accounted for 85.7% of both posterior ethmoid and sphenoid sinuses. Bone defects of the lamina papyracea at the optic canal and the vertical downward deviation of the optic nerve at each location, especially in 6/9 patients with Onodi cell mucocele, were characteristic in the poor group. In these conditions, increasing the contact areas of the optic nerve and mucocele can leads to more chances of direct downward compression of the optic nerve and infection occurring, and it may lead to severe pre-operative visual impairment. CONCLUSION: Imaging studies of optic neuropathy with mucocele help to determine the risk factors and perform early and precise diagnostic imaging and decision-making for surgery.

Surgeon effects on cataract refractive outcomes are minimal compared with patient comorbidity and gender: an analysis of 490 987 cases.

AIM: To investigate effect of patient age, gender, comorbidities and surgeon on refractive outcomes following cataract surgery. METHODS: Study population: patients on UK national ophthalmic cataract database on cataract operations undertaken between 1 April 2010 and 31 August 2018. Variables examined included gender, age, diabetic retinopathy, glaucoma, high myopia, inherited retinal disease, optic nerve disease, uveitis, pseudoexfoliation, vitreous opacities, retinal pathology, cataract type, previous surgery and posterior capsular rupture. A multivariate normal cross-classified model was fitted to the refractive outcome using Markov Chain Monte Carlo (MCMC) methods with diffuse priors to approximate maximum likelihood estimation. A MCMC chain was generated with a burn-in of 5000 iterations and a monitoring chain of 50 000 iterations. RESULTS: 490 987 cataract operations were performed on 351 864 patients by 2567 surgeons. Myopic and astigmatic errors were associated with posterior capsule rupture (-0.38/+0.04×72), glaucoma (-0.10/+0.05×95), previous vitrectomy (-0.049/+0.03×66) and high myopia (-0.07/+0.03×57). Hyperopic and astigmatic errors were associated with diabetic retinopathy (+0.08/+0.03×104), pseudoexfoliation (+0.07/+0.01×158), male gender (+0.12/+0.05×91) and age (-0.01/+0.06×97 per increasing decade). Inherited retinal disease, optic nerve disease, previous trabeculectomy, uveitis, brunescent/white cataract had no significant impact on the error of the refractive outcome. The effect of patient gender and comorbidity was additive. Surgeons only accounted for 4% of the unexplained variance in refractive outcome. CONCLUSION: Patient comorbidities and gender account for small but statistically significant differences in refractive outcome, which are additive. Surgeon effects are very small.

BARTONELLA HENSELAE -ASSOCIATED OPTIC NEUROPATHY PRESENTING AS A CENTRAL SCOTOMA IN THE ABSENCE OF OVERT PAPILLITIS: A MULTIMODAL IMAGING STUDY.

BACKGROUND/PURPOSE: The purpose of this report was to describe the use of multimodal imaging to establish the diagnosis of Bartonella henselae -associated optic neuropathy in a patient who presented with a central scotoma without overt evidence of optic nerve involvement. METHODS: This was a case report. Main outcome measures included clinical, optical coherence tomography, and fluorescein angiography findings. OBSERVATIONS: A 72-year-old woman presented with a 3-day history of central scotoma in the left eye. Her examination was remarkable for faint exudation in the nasal macula of the left eye but was otherwise normal for her age. Spectral domain optical coherence tomography of the macula revealed mild thickening of the papillomacular bundle with scattered small cystoid spaces and several intraretinal exudates, none of which were visible clinically. Fluorescein angiography revealed localized leakage of the inferotemporal optic disc. When prompted, the patient recalled being scratched multiple times by her two pet kittens. Serial testing showed rising anti- B. henselae ( B. henselae ) immunoglobulin G antibody titers to 1:1,280, confirming the suspected diagnosis of B. henselae -associated optic neuropathy. CONCLUSION: Bartonella -associated optic nerve involvement can occur without overt evidence of optic disc swelling. Multimodal imaging can be used to suggest the diagnosis and support appropriate serologic testing.

Neurovascular Compression in the Anterior Visual Pathway: A Case Series.

A retrospective review of 29 patients with neurovascular compression syndrome (NVCS) involving the anterior visual pathway was conducted. Various patterns of NVCS and visual defects were identified, most commonly involving the optic nerve and internal carotid artery. Most patients were stable, except one with progressive visual field defects. Although mostly asymptomatic, NVCS can rarely cause compressive optic neuropathy. NVCS should be kept in the differential diagnosis of normal tension glaucoma, especially with progressive visual loss despite treatment. Patients with progressive visual loss may require decompression surgery. Non-contrast computed tomography scan may miss NVCS, and magnetic resonance imaging is diagnostic.

Combined endonasal and orbital approach for annulus of Zinn area decompression in dysthyroid optic neuropathy.

BACKGROUND: Dysthyroid optic neuropathy (DON) is a serious complication of thyroid-associated ophthalmopathy (TAO) that can cause permanent vision loss from orbital apex syndrome. Urgent management of high-dose corticosteroid pulse therapy is recommended, and salvage orbital apex decompression surgery may require in refractory patients ineffective with corticosteroid pulse therapy. PURPOSE: To evaluate the short-term efficacy and safety of combined endoscopic endonasal and orbital approach decompression in the annulus of the Zinn (AZ) area in refractory dysthyroid optic neuropathy (DON). METHODS: In this retrospective study, patients who underwent combined endoscopic endonasal and orbital approach decompression around the AZ area for the treatment of refractory DON from May 2021 to March 2022 were enrolled. A total of 15 orbital apex were decompressed across 9 patients. The demographic, imaging, and surgical data, as well as preoperative and postoperative best corrected visual acuity (BCVA), proptosis degree and Modified-Chinese-TAO-QOL scores, were collected and assessed. The t-test was used to identify differences between preoperative and postoperative parameters: visual acuity, proptosis and QOL scores. RESULTS: The mean best corrected visual acuity (BCVA) improved from 0.79 ± 0.77 LogMAR preoperatively to 0.21 ± 0.27 LogMAR (P < 0.001) postoperatively. Additionally, proptosis decreased from 22.25 ± 2.01 mm to 18.42 ± 1.85 mm (P < 0.01), with an average decrease of 3.7 mm. The preoperative scores of the visual, psychological, and comprehensive components of QoL were 14.60 ± 9.08, 37.49 ± 6.26 and 26.75 ± 3.70, respectively, which significantly improved postoperatively to 54.18 ± 7.23, 68.78 ± 12.53 and 61.88 ± 9.37, respectively. The postoperative follow-up time ranged from 2 to 11 months, and the median follow-up time was 7 months. There was 1 case of transient postoperative sinusitis and 1 new case of transient diplopia, which was relieved after 3 months. CONCLUSION: Combined endoscopic endonasal and orbital approach adequate decompression for AZ area significantly improves visual acuity and QOL in patients with DON.

Optic Disc Drusen in Patients With Ocular Hypertension: A Case Series and Review of the Literature.

BACKGROUND: The identification of glaucomatous optic neuropathy in the setting of optic disc drusen (ODD) is a challenge, and the decision of whether to offer treatment in the form of intraocular pressure (IOP) reduction is controversial. Here, we present a series of patients with coexisting ocular hypertension and ODD to evaluate clinical features, treatment options, and progression of optic neuropathy. In addition, a review of the literature on ODD with elevated IOP is provided. METHODS: Six patients with ODD and a history of ocular hypertension are presented. Components of the examination and imaging modalities used to establish the diagnosis of ODD were recorded and a description of ocular hypertension history, glaucoma testing, and the potential treatment of IOP were also provided. RESULTS: In this series, 4 of 6 patients with concurrent ocular hypertension and ODD showed progression of optic neuropathy as assessed by visual field or retinal nerve fiber layer thickness. Of the 2 patients who did not show evidence of progression, 1 was treated with IOP-lowering medications and 1 was observed off treatment. Of the 4 patients who showed evidence of progression, all 4 were initially treated with IOP-lowering medications and 2 ultimately went on to have trabeculectomy surgery. In the patients with progressive optic neuropathy, lowering the IOP seemed to halt the progression suggesting there was a pressure-sensitive component. CONCLUSIONS: Distinguishing changes to the optic nerve, particularly the structural changes at the lamina cribrosa of true glaucomatous optic neuropathy in the setting of ODD, is a challenge. Careful consideration of risk factors including age, presenting features, progression indicators, and management goals is to be accounted for in the decision to offer treatment. We see the presence ODD in the patients with ocular hypertension as an additional risk for progressive changes to the nerve fiber layer and visual field that needs to be considered when determining whether to initiate therapy. Our data suggest that treatment of IOP in the patients with ocular hypertension with ODD and evidence of progression reduces the risk of further progression. Further work is needed to determine whether progression of optic neuropathy in the setting of coexisting ODD and ocular hypertension is related mechanistically to predominantly an ODD-type process, a glaucomatous process, or a combination thereof.

Optic neuropathy associated with GVHD after bone marrow allogeneic hematopoietic stem cell transplantation for B-Acute lymphoblastic leukemia: case report.

BACKGROUND: Graft-versus-host disease (GVHD) is the most common complication after bone marrow allogeneic hematopoietic stem cell transplantation (allo-HSCT). The incidence of posterior segment complications was significantly lower than that of ocular surface lesions. Up to now, there has been no report about optic neuropathy associated with GVHD. CASE PRESENTATION: A 23-year-old man presented with visual acuity decline after allo-HSCT for B-acute lymphoblastic leukemia (B-ALL). Red rashes were found all over the body simultaneously. Visual field examination revealed central scotomas in both eyes. Visual evoked potential showed prolonged P100 latency and decreased P100 amplitude in both eyes. Other ocular examinations showed no obvious abnormality except for blunt pupillary light reflex. The minimal residual disease test was negative after transplantation, and no obvious abnormalities were found in optic nerve and brain by magnetic resonance imaging (MRI). After the multi-disciplinary consultation, the rashes and optic neuropathy were considered GVHD probably. As for the treatment, methylprednisolone and Ruxolitinib were suggested, supported by adjunctive neurotrophic therapy. Two months later, the rashes gradually subsided. However, the visual acuity was not significantly improved at latest follow-up. CONCLUSIONS: The present case report demonstrated GVHD probably associated with optic neuropathy. Although extremely rare, optic nerve should be considered as a potential target of ocular GVHD, which could expand the dimensions of GVHD.

The Changes in Optic Nerve after Orbital Decompression Surgery for Thyroid Eye Disease and Case Reports of Ischemic Optic Neuropathy.

Purpose: To demonstrate the changes in the retinal nerve fiber layer (RNFL) after orbital decompression for thyroid eye disease (TED). Methods: We retrospectively enrolled 52 surgical TED patients, 30 nonsurgical TED patients, and 30 control subjects. Five surgical TED eyes with disc edema were excluded. The surgical TED patients were classified into the "dysthyroid optic neuropathy (DON)" group (16 eyes) and the "non-DON" group (83 eyes). Optical coherence tomography (OCT) and visual field (VF) examinations were performed preoperatively and 6 months later. The control subjects and nonsurgical TED patients received two OCT examinations at 6-month intervals. The postoperative changes in the RNFL thickness were compared between groups. Three cases with severe postoperative vision loss were presented additionally. Results: The changes in the RNFL thickness of the controls (0.5 ± 3.4 µm) and the nonsurgical TED patients (0.3 ± 2.8 µm) were significantly smaller than the surgical TED patients (P < 0.001). The DON group (-9.2 ± 9.2 µm) had greater RNFL thickness reduction than the non-DON group (-3.9 ± 5.4 µm) (P = 0.002). Bone removal decompression was associated with decreased RNFL in the non-DON (P = 0.025; ß = -2.49) and DON (P = 0.042; ß = -9.43) groups. Three cases who were hard to operate due to extensive fibrosis experienced severe vision loss postoperatively due to anterior ischemic optic neuropathy, posterior ischemic optic neuropathy, and posterior ciliary artery occlusion, respectively. Conclusions: TED patients experienced subclinical optic nerve injury and significant RNFL loss after the orbital decompression surgery. Aggressive manipulation during decompression surgery may lead to dreadful vision loss. Tailored surgical plans and delicate manipulation are warranted.

A rare pediatric case of McCune-Albright syndrome with acute visual disturbance: Case report.

RATIONALE: McCune-Albright syndrome (MAS) is a rare disorder characterized by clinical findings, which includes fibrous dysplasia (FD). FD is a benign tumor that leads to increased rates of bone fracture. In some MAS cases with FD, facial deformities, severe pain, and orbital neuropathies are complicated. Aneurysmal bone cyst (ABC) is a benign bone tumor and rare complication of FD. PATIENT CONCERNS: A 9-year-old boy was admitted to our hospital because of acute visual disturbance. DIAGNOSIS AND INTERVENTIONS: The patient was clinically diagnosed as ABC complicated with MAS, and he underwent surgery. OUTCOMES: After the surgery, his sight became normal. Recurrence of ABC and visual disturbance was not observed in 3 years. Genetic analysis of a tissue sample from the ABC lesion by next-generation sequencing revealed a somatic activating GNAS mutation. LESSONS: To the best of our knowledge, this is the first case report of MAS causing optic neuropathy complicated with ABC. ABC complicated with MAS is extremely rare, but it should be considered as a possible diagnosis in patients with acute visual loss and facial swelling. In addition, our case had OAS, which is an uncommon syndrome and a rare complication in ABC with MAS, and rapid decompression of the ABC was effective in improving the patient's eyesight.

Clinical Features of Acute Retinal Necrosis with Optic Neuropathy and Central Retinal Artery Occlusion as Initial Manifestations.

Acute retinal necrosis normally occurs at the periphery retina and gradually merges and progresses to the posterior pole. Optic neuropathy and central retinal artery occlusion as initial manifestation is very rare. We report the case of a patient with optic neuropathy and central retinal vessels as the first manifestations of acute retinal necrosis. Antiviral drugs, corticosteroids, and drugs that improve blood circulation were given. The necrotic retina and swollen optic disc disappeared gradually. However, the final vision of this eye declined to no light perception. From the first case report in 2001 to now, a total of 8 sporadic cases have been reported. The average onset age is 60.85±14.05 years. Most of them had no history of virus infection. Cardiovascular disease history maybe a risk factor. Acute retinal necrosis should be considered in patients with retinal vascular occlusion accompanied by granulomatous anterior uveitis. Further research is needed to determine whether treatments in addition to antiviral and corticosteroid therapy are needed.

Multicolor Imaging for the Detection of Inner Nuclear Layer Microcysts Secondary to Optic Nerve Atrophy.

ABSTRACT: Inner nuclear layer (INL) microcysts have been reported in diseases affecting the optic nerve. The new ocular imaging techniques detect minimal structural alterations at the macula and correlate these findings to different etiologies with less invasive procedures. The relationship between ganglion cells distribution at the macula and chiasmal nerve fibers enables the diagnosis and location of neurological lesions by new generation optical coherence tomography (SD-OCT) imaging devices. We report the evaluation of a patient with a history of optic nerve trauma and macular INL microcysts with multicolor SD-OCT technology that shows a pattern that localizes the lesion to the left optic nerve and proximal segment of the chiasm.

Unilateral Isolated Paucisymptomatic Optic Disc Edema.

BACKGROUND: Unilateral isolated optic disc edema (UIODE) represents a challenging clinical presentation that frequently precipitates an extensive diagnostic work-up. Patients without an apparent diagnosis despite appropriate investigations are often categorized as having "papillophlebitis," an entity that is poorly defined in the existing literature. Our aim was to describe the characteristics of a series of patients with paucisymptomatic UIODE, determine the optimal diagnostic approach to such cases, and clarify the clinical features of presumed papillophlebitis. METHODS: We retrospectively identified 29 patients with UIODE who were seen by neuro-ophthalmologists at a single center between 2005 and 2019. Each patient presented with isolated, unilateral disc edema that was either entirely asymptomatic or associated with minimal visual symptoms. Patients underwent a comprehensive neuro-ophthalmic evaluation and several ophthalmic and systemic investigations. Data from the initial visit and all subsequent clinical visits were collected, including patient demographics, examination findings, and details of the diagnostic work-up. RESULTS: Our 29 patients with UIODE were found to have a variety of underlying diagnoses including unilateral papilledema due to idiopathic intracranial hypertension (10 patients), optic nerve sheath meningioma (5), incipient nonarteritic anterior ischemic neuropathy (4), vitreopapillary traction (3), orbital masses (2), a peripapillary choroidal neovascular membrane (1), and presumed papillophlebitis (4). The duration of disc edema varied considerably based on the etiology, but most patients had favorable visual outcomes. CONCLUSIONS: A systematic approach to the evaluation of UIODE, combined with long-term follow-up, led to a definite diagnosis in a majority of patients, with only 4 patients presumed to have papillophlebitis, a diagnosis the actual existence of which remains controversial.

Reversible optic neuropathy secondary to metronidazole.

Metronidazole is a nitroimidazole antibiotic used in treating anaerobic bacteria and protozoal infections. It was first licensed for the treatment of Trichomonas vaginalis but is now used in the management of various gastrointestinal and genitourinary infections. Many neurological side effects are well documented, although there is scarce literature illustrating optic neuropathy secondary to metronidazole. We describe a case report of a 36-year-old man who presented with symptomatically reduced central visual loss on a background of a 2-year history of metronidazole use for a perianal fistula. Electrophysiology demonstrated bilateral optic neuropathy, with pattern visual evoked potential traces demonstrating marked latency and small amplitude responses of the P100 waves, which improved to within normal limits on cessation of metronidazole. This case study demonstrates clinical and electrophysiological reversibility of optic neuropathy secondary to high dose and prolonged metronidazole use.

Results of Neuroimaging in Patients with Atypical Normal-Tension Glaucoma.

AIM: The aim of the study was to determine the frequency of pathologies which can mimic normal-tension glaucoma (NTG), observed in neuroimaging of NTG patients, and to evaluate the frequency of pathologies in determined additional indications for neuroimaging. Material and Methods. The studied group consisted of 126 NTG patients who met at least one of the following criteria: unilateral NTG, damage in the visual field (VF) inconsistent with optic disc appearance, fast VF progression, worsening of visual acuity, predominant optic disc pallor rather than optic disc excavation, diagnosis under the age of 50, and scotoma in VF restricted by a vertical line. The patients included in the research underwent MRI scans of the brain and both orbits. RESULTS: After neuroimaging, the results of 29 (23%) patients were qualified as positive; 18 (14.2%) of the identified pathologies were found to clinically affect the visual pathway. The most frequent brain pathology was intracranial meningiomas, observed in 4 patients (3.1%), followed by optic nerve sheath meningiomas diagnosed in 3 cases (2.4%), and brain glioma in 1 patient (0.8%). Pituitary gland adenomas were described in 6 patients (4.5%); 3 of the tumours were in contact with the optic chiasm. 53 (40%) patients had minimal ischemic changes in different regions of the brain. In the case of worsening BCVA or fast VF progression, the frequency of positive results was the highest (50% and 40%), whereas in the case of diagnosis at a young age and unilateral involvement, neuropathology was the rarest (0% and 6.9%). CONCLUSIONS: In the case of NTG, the decision to perform neuroimaging should be made after a detailed assessment of clinical status, rather in the event of finding the signs of possible compressive optic neuropathy than as an obligatory procedure for every patient.