Faculty Bibliography

As all other aspects in times of the coronavirus disease (COVID)-19 pandemic, carrying-out quality clinical research has been challenging. Many well-established paradigms have shifted as a consequence of the rapid demand for new knowledge. New treatments are fast-moving, informed consent forms are difficult to obtain, a competitive invitation from researchers to participate in different studies is common, and non-COVID-19 research protocols are suffering continuity. However, these challenges should not imply taking shortcuts or accepting deficiencies in bioethical standards, but rather enhance the alertness for rigorous ethical approaches despite these less than ideal circumstances. In this manuscript, we point out some interrogates in COVID-19 research and outline possible strategies to overcome the difficult task to continue with high-quality research without violating the ethical principles.

The offline "replay" of neural firing patterns underlying waking experience, previously observed in non-human animals, is thought to be a mechanism for memory consolidation. Here, we test for replay in the human brain by recording spiking activity from the motor cortex of two participants who had intracortical microelectrode arrays placed chronically as part of a brain-computer interface pilot clinical trial. Participants took a nap before and after playing a neurally controlled sequence-copying game that consists of many repetitions of one "repeated" sequence sparsely interleaved with varying "control" sequences. Both participants performed repeated sequences more accurately than control sequences, consistent with learning. We compare the firing rate patterns that caused the cursor movements when performing each sequence to firing rate patterns throughout both rest periods. Correlations with repeated sequences increase more from pre- to post-task rest than do correlations with control sequences, providing direct evidence of learning-related replay in the human brain.

Background There is growing recognition that positive health beliefs may promote blood pressure (BP) reduction, which is critical to stroke prevention but remains a persistent challenge. Yet, studies that examine the association between positive health beliefs and BP among stroke survivors are lacking. Methods and Results Data came from the DESERVE (Discharge Educational Strategies for Reduction of Vascular Events) study, a randomized controlled trial of a skills-based behavioral intervention to reduce vascular risk in a multiethnic cohort of 552 transient ischemic attack and mild/moderate stroke patients in New York City. The exposure was perception that people can protect themselves from having a stroke (ie, prevention self-efficacy) at baseline. The association between systolic BP (SBP) reduction at 12-month follow-up and self-efficacy was examined using linear regression adjusted for key confounders, overall and stratified by age, sex, race/ethnicity, and intervention trial arm. Approximately three quarters endorsed self-efficacy. These participants had, on average, 5.6 mm Hg greater SBP reduction compared with those who did not endorse it (95% CI, 0.5-10.7 mm Hg; P=0.032). Self-efficacy was significantly associated with greater SBP reduction, particularly among female versus male, younger versus older, and Hispanic versus non-Hispanic white patients. Sensitivity analysis adjusting for baseline SBP instead of elevated BP yielded no association between self-efficacy and SBP reduction, but showed sex differences in this association (women: β=5.3; 95% CI, -0.2 to 10.8; P=0.057; men: β=-3.3; 95% CI, -9.4 to 2.9; P=0.300; interaction P=0.064). Conclusions Self-efficacy was linked with greater SBP reduction among female stroke survivors. Targeted strategies to improve health beliefs after stroke may be important for risk factor management. REGISTRATION URL: https://www.clini​caltr​ials.gov; Unique identifier: NCT01836354.

Deep learning (DL) methods have in recent years yielded impressive results in medical imaging, with the potential to function as clinical aid to radiologists. However, DL models in medical imaging are often trained on public research cohorts with images acquired with a single scanner or with strict protocol harmonization, which is not representative of a clinical setting. The aim of this study was to investigate how well a DL model performs in unseen clinical datasets-collected with different scanners, protocols and disease populations-and whether more heterogeneous training data improves generalization. In total, 3117 MRI scans of brains from multiple dementia research cohorts and memory clinics, that had been visually rated by a neuroradiologist according to Scheltens' scale of medial temporal atrophy (MTA), were included in this study. By training multiple versions of a convolutional neural network on different subsets of this data to predict MTA ratings, we assessed the impact of including images from a wider distribution during training had on performance in external memory clinic data. Our results showed that our model generalized well to datasets acquired with similar protocols as the training data, but substantially worse in clinical cohorts with visibly different tissue contrasts in the images. This implies that future DL studies investigating performance in out-of-distribution (OOD) MRI data need to assess multiple external cohorts for reliable results. Further, by including data from a wider range of scanners and protocols the performance improved in OOD data, which suggests that more heterogeneous training data makes the model generalize better. To conclude, this is the most comprehensive study to date investigating the domain shift in deep learning on MRI data, and we advocate rigorous evaluation of DL models on clinical data prior to being certified for deployment.

Blindness and vision impairment are unpredictable complications of tuberculous meningitis (TBM) that are often unrecognized in the acute stages of illness due to inability to assess vision in patients with depressed levels of consciousness or confusion. We present a patient with definite TBM confirmed by positive Xpert MTB/RIF assay of cerebrospinal fluid (CSF) who developed binocular blindness two weeks after diagnosis and initiation of standard anti-tuberculosis treatment (ATT). Ophthalmological exam demonstrated complete bilateral abducens nerve palsies, impaired pupillary responses to light, normal optic discs, and visual acuity of hand motion only in each eye. Brain CT showed progressive enlargement of the third and lateral ventricles. We managed the patient medically with dexamethasone, acetazolamide, and substitution of moxifloxacin for ethambutol. Serial brain CTs confirmed gradual resolution of hydrocephalus. The patient had complete neurological recovery at six months except for residual blindness in the right eye. Visual acuity in the left eye recovered to normal (20/20). The assessment and management of vision impairment in TBM is discussed.

OBJECTIVE:To outline strategies for the treatment of migraine which do not require in-person visits to clinic or the emergency department, and to describe ways that health insurance companies can remove barriers to quality care for migraine. BACKGROUND:COVID-19 is a global pandemic causing widespread infections and death. To control the spread of infection we are called to observe "social distancing" and we have been asked to postpone any procedures which are not essential. Since procedural therapies are a mainstay of headache care, the inability to do procedures could negatively affect our patients with migraine. In this manuscript we review alternative therapies, with particular attention to those which may be contra-indicated in the setting of COVID-19 infection. DESIGN/RESULTS/UNASSIGNED:The manuscript reviews the use of telemedicine visits and acute, bridge, and preventive therapies for migraine. We focus on evidence-based treatment where possible, but also describe "real world" strategies which may be tried. In each section we call out areas where changes to rules from commercial health insurance companies would facilitate better migraine care. CONCLUSIONS:Our common goal as health care providers is to maximize the health and safety of our patients. Successful management of migraine with avoidance of in-person clinic and emergency department visits further benefits the current urgent societal goal of maintaining social distance to contain the COVID-19 pandemic.

BACKGROUND AND PURPOSE/OBJECTIVE:The brain stem is a complex configuration of small nuclei and pathways for motor, sensory, and autonomic control that are essential for life, yet internal brain stem anatomy is difficult to characterize in living subjects. We hypothesized that the 3D fast gray matter acquisition T1 inversion recovery sequence, which uses a short inversion time to suppress signal from white matter, could improve contrast resolution of brain stem pathways and nuclei with 3T MR imaging. MATERIALS AND METHODS/METHODS:-space to reduce motion; total scan time = 58 minutes). One subject returned for an additional 5-average study that was combined with a previous session to create a highest quality atlas for anatomic assignments. A 1-mm isotropic resolution, 12-minute version, proved successful in a patient with a prior infarct. RESULTS:The fast gray matter acquisition T1 inversion recovery sequence generated excellent contrast resolution of small brain stem pathways in all 3 planes for all 10 subjects. Several nuclei could be resolved directly by image contrast alone or indirectly located due to bordering visualized structures (eg, locus coeruleus and pedunculopontine nucleus). CONCLUSIONS:The fast gray matter acquisition T1 inversion recovery sequence has the potential to provide imaging correlates to clinical conditions that affect the brain stem, improve neurosurgical navigation, validate diffusion tractography of the brain stem, and generate a 3D atlas for automatic parcellation of specific brain stem structures.

BACKGROUND:Verification of complete occlusion or resection of neurovascular lesions is often done with intraoperative angiography. Surgery for spinal vascular lesions such as arteriovenous malformations (AVMs) and arteriovenous fistulas (AVFs) is typically performed in the prone position making intraoperative angiography difficult. There is no standardized protocol for intraoperative angiography in spinal surgeries performed in the prone position. OBJECTIVE:We describe our experience with using radial artery access for intraoperative angiography in thoracic spinal neurovascular procedures performed with patients in the prone position. METHODS:We reviewed all patients who underwent surgical resection of spinal vascular lesions in the prone position with radial artery vascular access for intraoperative angiography. Patients were treated in a hybrid endovascular operating room. RESULTS:4 patients were treated in the pone position utilizing transradial artery access intraoperative angiography for confirmation of complete resection of the vascular lesions. 2 patients were operated for dural AVFs, one patient had a pial AVF, and one patient had an AVM of the filum terminale. None of the patients faced any procedural complications. CONCLUSION/CONCLUSIONS:Radial artery access for intraoperative angiography in spinal neurovascular procedures in which selective catheterization of a thoracic branch is necessary, is feasible, safe, and practical.