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Over 15 million epilepsy patients worldwide have drug-resistant epilepsy. Successful surgery is a standard of care treatment but can only be achieved through complete resection or disconnection of the epileptogenic zone, the brain region(s) where seizures originate. Surgical success rates vary between 20% and 80%, because no clinically validated biological markers of the epileptogenic zone exist. Localizing the epileptogenic zone is a costly and time-consuming process, which often requires days to weeks of intracranial EEG (iEEG) monitoring. Clinicians visually inspect iEEG data to identify abnormal activity on individual channels occurring immediately before seizures or spikes that occur interictally (i.e. between seizures). In the end, the clinical standard mainly relies on a small proportion of the iEEG data captured to assist in epileptogenic zone localization (minutes of seizure data versus days of recordings), missing opportunities to leverage these largely ignored interictal data to better diagnose and treat patients. IEEG offers a unique opportunity to observe epileptic cortical network dynamics but waiting for seizures increases patient risks associated with invasive monitoring. In this study, we aimed to leverage interictal iEEG data by developing a new network-based interictal iEEG marker of the epileptogenic zone. We hypothesized that when a patient is not clinically seizing, it is because the epileptogenic zone is inhibited by other regions. We developed an algorithm that identifies two groups of nodes from the interictal iEEG network: those that are continuously inhibiting a set of neighbouring nodes ('sources') and the inhibited nodes themselves ('sinks'). Specifically, patient-specific dynamical network models were estimated from minutes of iEEG and their connectivity properties revealed top sources and sinks in the network, with each node being quantified by source-sink metrics. We validated the algorithm in a retrospective analysis of 65 patients. The source-sink metrics identified epileptogenic regions with 73% accuracy and clinicians agreed with the algorithm in 93% of seizure-free patients. The algorithm was further validated by using the metrics of the annotated epileptogenic zone to predict surgical outcomes. The source-sink metrics predicted outcomes with an accuracy of 79% compared to an accuracy of 43% for clinicians' predictions (surgical success rate of this dataset). In failed outcomes, we identified brain regions with high metrics that were untreated. When compared with high frequency oscillations, the most commonly proposed interictal iEEG feature for epileptogenic zone localization, source-sink metrics outperformed in predictive power (by a factor of 1.2), suggesting they may be an interictal iEEG fingerprint of the epileptogenic zone.
Assuntos
Epilepsia , Convulsões , Humanos , Estudos Retrospectivos , Eletrocorticografia/métodos , Epilepsia/diagnóstico , Epilepsia/cirurgia , BiomarcadoresRESUMO
Purpose: Trabeculectomy surgery is a commonly performed procedure for treatment of glaucoma. While the goal is to lower intraocular pressure, over-filtration may cause hypotony with ocular structural changes and vision loss. Observations: A 53-year-old woman with primary open-angle glaucoma was referred to our service for further evaluation. The patient previously underwent trabeculectomy 9 years prior and was found to have a cataract and hypotony maculopathy in the right eye. Treatment options included cataract surgery alone, bleb revision alone, or combined cataract extraction and bleb revision. Biometry revealed corneal astigmatism in the right eye, and significant disparity in axial length between the two eyes. Since the axial length and corneal astigmatic changes were presumed to be at least partially reversible, measurements from the non-operative left eye influenced the lens selection for the hypotonous right eye. The patient underwent combined phacoemulsification and bleb revision. While IOP increased and hypotony was partly reversed, there was hyperopic and astigmatic refractive surprise after surgery.The patient subsequently underwent intraocular lens exchange using biometric values of the previously hypotonous eye and met the target post-operative refractive goal. Conclusions and importance: This case demonstrates changes to the axial length and ocular structure following longstanding hypotony maculopathy may be permanent, even after restoration of normotensive intraocular pressure.
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Lens dislocation is a significant complication after cataract surgery. Scleral fixation of 3-piece intraocular lens provides favorable visual outcome and can spare patients the need for lens exchange. Two patients presented with dislocated 3-piece lenses implanted over 10 years earlier. Both patients underwent pars plana vitrectomy and dropped lens rescue with scleral fixation. Postoperatively, the lens optic was found flipped nearly 90° at the optic-haptic junctions secondary to fluid-air exchange performed during vitrectomy. Both patients underwent intraocular lens exchange with a four point sclera fixated lens. Our study found that air tamponade is better avoided during rescue of old dislocated 3-piece lens implants. Intraocular lens exchange is preferred, when possible, to avoid complications associated with old dislocated lenses. Larger studies are needed to determine the effect of time on dislocated lens implants materials.
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Purpose The purpose of the study is to determine if instructional videos detailing the use of smartphone accessibility features may be used to improve quality of life and comfort with phone usage among patients with severe glaucoma. Design The design of the present study is an interventional case series. Methods The patients with vision loss due to severe glaucoma were recruited from one institution. Two surveys were completed to provide baseline data: one detailed their current use of smartphone accessibility features, and the other provided survey was the EuroQol 5 Dimension 5 Level (EQ-5D-5L) (EuroQol Group, Rotterdam, Netherlands), which is used to assess the quality of life. Then, the patients were shown a brief video with instructions on configuring the use of voice-over, magnification, and zoom functions, along with other features. To conclude, the patients completed the same surveys either at follow-up visits or by phone calls. Results Fifteen patients were recruited to participate in the study. At baseline, the participants used a median of one accessibility feature, with the most common feature being "text sizing/bolding." At follow-up, the participants averaged the gain of use of one accessibility feature and reported a decrease in text messaging visual limitation, although these findings did not reach statistical significance. Overall, the quality of life, as measured by the EQ-5D-5L, demonstrated a non-statistically significant increase of six points. Conclusions Despite the lack of statistical significance, our results indicate that providing instructional videos may benefit the patients' ability to navigate on their smartphones. Incorporating links or Quick Response (QR) codes to these instructional videos provides an opportunity to improve the quality of life at no additional risk to the patient. Further studies are needed with an increased population to investigate for any significance of our findings.
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Rationale: Insular epilepsy can be a challenging diagnosis due to overlapping semiology and scalp EEG findings with frontal, temporal, and parietal lobe epilepsies. Stereotactic electroencephalography (sEEG) provides an opportunity to better localize seizure onset. The possibility of improved localization is balanced by implantation risk in this vascularly rich anatomic region. We review both safety and pre-implantation factors involved in insular electrode placement across four years at an academic medical center. Methods: Presurgical data, operative reports, and invasive EEG summaries were retrospectively reviewed for patients undergoing invasive epilepsy monitoring on the insula from 2016 through 2019. EEG reports were reviewed to record the presence of insula ictal and interictal involvement. We recorded which presurgical findings suggested insular involvement (insula lesion on MRI, insula changes on PET/SPECT/scalp EEG, characteristic semiology, or history of failed anterior temporal lobectomy). The likelihood of pre-sEEG insular onset was categorized as low suspicion if no presurgical findings were present ("rule out"), moderate suspicion if one finding was present, and high suspicion if two or more findings were present. Results: 76 patients received 189 insular electrodes as part of their implantation strategy for 79 surgical cases. Seven patients (8.9%) had insular ictal onset. One clinically significant complication (left hemiparesis) occurred in a patient with moderate suspicion for insular onset. There were 38 low suspicion cases, 36 moderate suspicion cases, and 5 high suspicion cases for pre-sEEG insula ictal onset. Two low suspicion (5.3%), three moderate suspicion (8.6%), and two high suspicion (40%) cases had insular ictal onset. Conclusions: The insula can safely receive sEEG. Having two or more presurgical factors indicating insular onset is a strong, albeit incomplete, predictor of insular seizure onset. Using pre-implantation clinical findings can offer clinicians predictive value for targeting the insula during invasive EEG monitoring.
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PURPOSE: To report a case of frosted branch angiitis presenting in a pediatric patient with unremarkable laboratory work-up apart from SARS-CoV-2 IgG antibodies. OBSERVATIONS: Less than four weeks after a SARS-CoV-2 infection, a 10 year-old female presented to the emergency department with severe headache and intermittent fevers. During her hospital admission, the ophthalmology service was consulted for blurry vision. Subsequent eye examination revealed frosted branch angiitis. The patient initially received intravenous corticosteroids but was escalated to plasmapheresis to achieve resolution of her symptoms. Outpatient maintenance therapy consisted of an oral Prednisone taper and Infliximab infusion. CONCLUSION AND IMPORTANCE: This case represents a unique ocular manifestation of COVID-19, as recent SARS-CoV-2 was the sole identifiable cause of the patient's frosted branch angiitis. Additionally, this patient required plasmapheresis to control disease progression.