Field changes on automated Humphrey’s field analyzer in tuberculosis following ethambutol therapy

This study was conducted to evaluate the visual field changes in tubercular patients on anti-tubercular therapy and to assess the reversibility of these changes after the discontinuation therapy. This study was conducted as a prospective analytical study at tertiary care centres in Bhopal and Jabalpur on all newly detected tuberculosis patients. Ocular history, relevant history was recorded and detailed ocular examination was done at the time of presentation, before initiating ATT. All the patients were followed up periodically till the cessation of treatment and three months thereafter. A total of 40 cases of newly diagnosed tuberculosis were registered with mean age of 38.4±13.99 years. We documented significant deterioration in visual acuity after 3 months of initiation of therapy. Once the ATT was stopped, the improvement in visual acuity was statistically significant 3 months after the cessation of ATT as compared to visual acuity 3 months after initiation of ATT (p<0.05). But residual visual impairment even after stoppage of ATT was observed. Color vison and visual field defects were observed in higher proportions of eyes following initiation of ethambutol which improved significantly after 3 months of cessation of ATT (p<0.05). Ethambutol, even in recommended dose according to DOTS, has been associated with ocular toxicity which manifests in the form of painless progressive loss of vision, color vision defects and visual field defects. Though these changes are usually reversible, few patients have irreversible damage. Thus, patients receiving ethambutol must be explained regarding these effects and followed up periodically.

Clinical Features and Surgical Management of Pituitary Adenoma During Pregnancy: Case Series and Literature Review

Purpose Although conservative treatment was recommended for pregnant patients with pituitary adenomas (PAs), surgical treatment is occasionally necessary for those with acute symptoms. However, surgical intervention among these patients is poorly studied. Methods Six patients with PAs who underwent surgical treatment during pregnancy at Peking Union Medical College Hospital between January 1990 and June 2021 and another 35 pregnant patients profiled in the literature were included. Results All the 41 enrolled patients (mean age 29.8 ± 5.3 years) had acute symptoms including visual field defects, severe headaches, or vision loss requiring emergency pituitary surgeries. Mean tumor diameter was 2.16 ± 0.9 cm, and 92.6% were macroadenomas. PA apoplexies were found in 23 patients. The average gestation time at surgery was 25.1 ± 7.1 weeks; 55.9% of these patients underwent surgery in the second trimester of pregnancy. Multidisciplinary team was involved from before surgery to after delivery. Except one patient underwent an induced abortion, and one fetus died due to a nuchal cord, thirty-nine patients delivered successfully, and 37 of fetuses were healthy till the last follow-up. One fetus died of congenital diaphragmatic hernia, and another had a low Apgar score after a cesarean section but survived. Conclusion PA surgery for pregnant patients with PAs is effective and safe during the second and third trimesters. Pregnant patients requiring emergency PA surgery need multidisciplinary evaluation and healthcare management. Cooperation of neurosurgery, endocrinology, obstetrics, anesthesiology, and neonatology is necessary for a successful surgical intervention for pregnant patients with PAs.

Glaucoma Diagnostic Performance of Macular Ganglion Cell Complex Thickness Using Regular and Long Axial Length Normative Databases

The risks of misdiagnosing a healthy individual as glaucomatous or vice versa may be high in a population with a large majority of highly myopic individuals, due to considerable morphologic variability in high myopic fundus. This study aims to compare the diagnostic ability of the regular and long axial length databases in the RS-3000 Advance SD-OCT (Nidek) device to correctly diagnose glaucoma with high myopia. Patients with high myopia (axial length ≥ 26.0 mm) in Chang Gung Memorial Hospital, Taiwan between 2015 and 2020 were included. Glaucoma was diagnosed based on glaucomatous discs, visual field defects and corresponding retinal nerve fiber layer defects. The sensitivity, specificity, diagnostic accuracy and likelihood ratios of diagnosing glaucoma via mGCC thickness in both superior/inferior and GChart mapping using the regular and long axial length normative databases. The specificity and diagnostic accuracy of mGCC thickness for distinguishing glaucomatous eyes from nonglaucomatous eyes among highly myopic eyes were significantly improved using the long axial length database (p=0.046). There were also significant proportion changes in S/I mapping as well as GChart mapping (37.3% and 48.0%, respectively; p<0.01) from abnormal to normal in the myopic normal eye group when using the long axial length normative database. The study revealed that clinicians could utilize a long axial length database to effectively decrease the number of false-positive diagnoses or to correctly identify highly myopic normal eyes misdiagnosed as glaucomatous eyes.

Acute to Subacute Spinal Cord Infarction Mimicking Acute Multiple Sclerosis: Usefulness of Diffusion-Weighted MRI for Diagnosis

Background: Spinal cord infarction (SCI) is difficult to diagnose because of its rarity, unknown etiology, and unestablished diagnostic criteria. Additionally, the timeline of SCI has not been studied in detail, as few studies using diffusion-weighted image (DWI) sequences of the spine of a small target population have been previously conducted. Case Study: A 56-year-old male with underlying arrhythmia suddenly developed visual field defects on the right side, pain in the left upper extremity, and a tingling sensation in the left hand. Brain Magnetic resonance imaging (MRI) revealed acute to subacute stages of multifocal brain infarction. On additional cervical spinal MRI, it showed atypical MRI findings of SCI, considered late acute to early subacute phase, which were similar to those seen in the acute phase of multiple sclerosis (MS). Additional DWI revealed restricted diffusion. From these findings, it could be inferred that the patient’s SCI occurred at the same time as the multifocal brain infarctions caused by atrial fibrillation. Conclusion: A DWI sequence of spine MRI could be helpful in the diagnosis of acute to subacute phase SCI and in differentiating with acute MS.

Long-Term Outcomes of Patients with Acromegaly - A Report from the Swedish Pituitary Register

Objective: To describe treatment and long-term outcomes of patients with acromegaly from all health-care regions in Sweden. Design and Methods: Analysis of prospectively reported data from the Swedish Pituitary Register of 698 patients (51% females) with acromegaly diagnosed from 1991-2011. The latest clinical follow-up date was December, 2012, while mortality data were collected for 28.5 years until June, 2019. Results: The annual incidence was 3.7/million; 71% of patients had a macroadenoma, 18% had visual field defects, and 25% had at least one pituitary hormone deficiency. Eighty-two percent had pituitary surgery, 10% radiotherapy and 39% medical treatment. At the 5- and 10-year follow-ups, IGF-I levels were within the reference range in 69% and 78% of patients, respectively. In linear regression the proportion of patients with biochemical control including adjuvant therapy at 10 year follow-up increased over time with 1.23 % per year. The SMR (95% CI) for all patients was 1.29 (1.11-1.49). For patients with biochemical control at the latest follow-up, SMR was not increased, neither among patients diagnosed 1991-2000, SMR 1.06 (0.85-1.33) or 2001-2011, SMR 0.87 (0.61-1.24). In contrast, non- controlled patients at the latest follow up from both decades had elevated SMR, 1.90 (1.33-2.72) and 1.98 (1.24-3.14), respectively. Conclusions: The proportion of patients with biochemical control increased over time. Patients with biochemically controlled acromegaly have normal life expectancy while non-controlled patients still have increased mortality. The high rate of macroadenomas and unchanged age at diagnosis illustrates the need for improvements in the management of patients with acromegaly.

Resting-state Functional Connectivity After Occipital Stroke

Background Resting-state functional magnetic resonance imaging (rsfMRI) reflects spontaneous activation of cortical networks. After stroke, these networks reorganize, both due to structural lesion and reorganization of functional connectivity (FC). Objective We studied FC in chronic phase occipital stroke patients with homonymous visual field defects before and after repetitive transorbital alternating current stimulation (rtACS). Methods This spin-off study, embedded in the randomized, sham-controlled REVIS trial, comprised 16 chronic occipital stroke patients with visual field defect and 12 healthy control subjects. The patients underwent rsfMRI at baseline, after two weeks of rtACS or sham treatment, and after two months of treatment-free follow-up, whereas the control subjects were measured once. We used a multivariate regression connectivity model to determine mutual prediction accuracy between 74 cortical regions of interest. Additionally, the model parameters were included into a graph to analyze average path length, centrality eigenvector, centrality degree, and clustering of the network. The patients and controls at baseline and the two treatment groups were compared with multilevel modeling. Results Before treatment, the patients and controls had similar whole-network prediction accuracy and network parameters, whereas centrality eigenvector differed in perilesional regions, indicating local modification in connectivity. In line with behavioral results, neither prediction accuracy nor any network parameter changed systematically as a result of rtACS rehabilitation compared to sham. Conclusions Whole-network FC showed no difference between occipital stroke patients and healthy population, congruent with the peripheral location of the visual network in relation to the high-density cortical core. rtACS treatment in the given setting did not affect FC.

How lesions at different locations along the visual pathway influence pupillary reactions to chromatic stimuli

Purpose To examine systematically how prechiasmal, chiasmal, and postchiasmal lesions along the visual pathway affect the respective pupillary responses to specific local monochromatic stimuli. Methods Chromatic pupil campimetry (CPC) was performed in three patient groups (10 subjects with status after anterior ischemic optic neuropathy, 6 with chiasmal lesions, and 12 with optic tract or occipital lobe lesions (tumor, ischemia)) using red, low-intensity red, and blue local stimuli within the central 30° visual field. Affected areas - as determined by visual field defects revealed using conventional static perimetry - were compared with non-affected areas. Outcome parameters were the relative maximal constriction amplitude (relMCA) and the latency to constriction onset of the pupillary responses. Results A statistically significant relMCA reduction was observed in the affected areas of postchiasmal lesions with red (p = 0.004) and low-intensity red stimulation (p = 0.001). RelMCA reduction in the affected areas seemed more pronounced for low-intensity red stimulation (46.5% mean reduction compared to non-affected areas; 36% for red stimulation), however statistically not significant. In prechiasmal lesions, a statistically significant latency prolongation could be demonstrated in the affected areas with low-intensity red stimulation (p = 0.015). Conclusion Our results indicate that the choice of stimulus characteristics is relevant in detecting defects in the pupillary pathway of impairment along the visual pathway, favoring red stimuli of low intensity over blue stimuli. Such knowledge opens the door for further fundamental research in pupillary pathways and is important for future clinical application of pupillography in neuro-ophthalmologic patients.

When You Do Not Get the Whole Picture: Scene Perception After Occipital Cortex Lesions

Background: Occipital cortex lesions (OCLs) typically result in visual field defects (VFDs) contralateral to the damage. VFDs are usually mapped with perimetry involving the detection of point targets. This, however, ignores the important role of integration of visual information across locations in many tasks of everyday life. Here, we ask whether standard perimetry can fully characterize the consequences of OCLs. We compare performance on a rapid scene discrimination task of OCL participants and healthy observers with simulated VFDs. While the healthy observers will only suffer the loss of part of the visual scene, the damage in the OCL participants may further compromise global visual processing.Methods: VFDs were mapped with Humphrey perimetry, and participants performed two rapid scene discrimination tasks. In healthy participants, the VFDs were simulated with hemi- and quadrant occlusions. Additionally, the GIST model, a computational model of scene recognition, was used to make individual predictions based on the VFDs.Results: The GIST model was able to predict the performance of controls regarding the effects of the local occlusion. Using the individual predictions of the GIST model, we can determine that the variability between the OCL participants is much larger than the extent of the VFD could account for. The OCL participants can further be categorized as performing worse, the same, or better as their VFD would predict.Conclusions: While in healthy observers the extent of the simulated occlusion accounts for their performance loss, the OCL participants’ performance is not fully determined by the extent or shape of their VFD as measured with Humphrey perimetry. While some OCL participants are indeed only limited by the local occlusion of the scene, for others, the lesions compromised the visual network in a more global and disruptive way. Yet one outperformed a healthy observer, suggesting a possible adaptation to the VFD. Preliminary analysis of neuroimaging data suggests that damage to the lateral geniculate nucleus and corpus callosum might be associated with the larger disruption of rapid scene discrimination. We believe our approach offers a useful behavioral tool for investigating why similar VFDs can produce widely differing limitations in everyday life.

Role of Oxidative Stress in Ocular Diseases Associated with Retinal Ganglion Cells Degeneration

Ocular diseases associated with retinal ganglion cell (RGC) degeneration is the most common neurodegenerative disorder that causes irreversible blindness worldwide. It is characterized by visual field defects and progressive optic nerve atrophy. The underlying pathophysiology and mechanisms of RGC degeneration in several ocular diseases remain largely unknown. RGCs are a population of central nervous system neurons, with their soma located in the retina and long axons that extend through the optic nerve to form distal terminals and connections in the brain. Because of this unique cytoarchitecture and highly compartmentalized energy demand, RGCs are highly mitochondrial-dependent for adenosine triphosphate (ATP) production. Recently, oxidative stress and mitochondrial dysfunction have been found to be the principal mechanisms in RGC degeneration as well as in other neurodegenerative disorders. Here, we review the role of oxidative stress in several ocular diseases associated with RGC degenerations, including glaucoma, hereditary optic atrophy, inflammatory optic neuritis, ischemic optic neuropathy, traumatic optic neuropathy, and drug toxicity. We also review experimental approaches using cell and animal models for research on the underlying mechanisms of RGC degeneration. Lastly, we discuss the application of antioxidants as a potential future therapy for the ocular diseases associated with RGC degenerations.

Research advance in optic disc tilt and rotation in high myopia and its implications for glaucoma and visual field defects

High myopia is of worldwide concern due to its high prevalence, and myopia is an independent risk factor for glaucoma. The purpose of this paper is to review the mechanism and clinical manifestations of optic disc tilt and rotation in high myopia and its relationship with glaucoma, to provide clues for monitoring fundus changes in high myopia and the early diagnosis of high myopia with glaucoma.