Real-time functional magnetic resonance imaging neurofeedback training of amygdala upregulation increases affective flexibility in depression.

BACKGROUND: Decreased affective flexibility is associated with depression symptoms, and it has been suggested that common interventions may target this mechanism. To explore this hypothesis, we evaluated whether real-time functional magnetic resonance imaging neurofeedback (rtfMRI-nf) training to increase the amygdala responses during positive memory recall resulted in both symptom improvements, as has been observed previously, and flexibility to decrease amygdala reactivity in response to a cognitive task among patients with major depressive disorder (MDD). METHODS: In a double-blind, placebo-controlled, randomized clinical trial, adults with MDD received 2 sessions of rtfMRI-nf training to increase their amygdala (experimental group) or parietal (control group) responses during positive autobiographical memory recall. We evaluated signal changes in the amygdala during both the positive memory neurofeedback and a subsequent counting condition. RESULTS: We included 38 adults with MDD, including 16 in the experimental group and 22 in the control group. In the experimental group, amygdala activity increased (t > 2.01, df < 27, p < 0.05, d > 0.5) and depressive symptoms decreased (-8.57, 95 % confidence interval [CI] -15.12 to -2.59; t 13 = -3.06, p = 0.009, d = 1). Amygdala activity during the count condition decreased after rtfMRI-nf (-0.16, 95 % CI -0.23 to -0.09; t 396 = 4.73, p < 0.001, d = 0.48) and was correlated with decreased depression scores (r = 0.46, p = 0.01). We replicated previous results and extended them to show decreased amygdala reactivity to a cognitive task during which no neurofeedback was provided. LIMITATIONS: The count condition was reported by participants as negative, but emotionality or accuracy during this condition was not assessed. CONCLUSION: These results suggest that nominally targeting unidimensional change in neural mechanisms could have implications for bidirectional control, increasing the likely reach and explanatory framework for how common depression interventions work.Trial registration: ClinicalTrials.gov NCT02709161.

Dopamine metabolite levels in the vitreous of diabetic and non-diabetic humans.

Animal studies suggest that the retinal dysfunction in diabetic subjects that precedes overt clinical vasculopathy may be due to a retinal dopamine deficit. We analyzed levels of dopamine (DA) and its primary metabolite, 3,4-dihydroxyphenylacetic acid (DOPAC), in the vitreous of diabetic and non-diabetic human subjects. Adult patients undergoing pars plana vitrectomy for non-hemorrhagic indications were prospectively recruited from the Emory Eye Center in Atlanta, GA. Vitreous samples were analyzed using high performance liquid chromatography (HPLC) to measure levels of DOPAC and DA in the vitreous specimens. Vitreous samples from 9 diabetic patients and 20 from non-diabetic patients were analyzed. No eyes had apparent diabetic retinopathy. Mean normalized DA concentration in vitreous of diabetic subjects was 0.76 ± 0.12 pg/µL vs. 0.73 ± 0.08 pg/µL in non-diabetic vitreous (p = 0.849). DOPAC concentration was 8.84 ± 0.74 pg/µL in vitreous of diabetic subjects vs. 9.22 ± 0.56 pg/µL in vitreous of non-diabetic subjects (p = 0.691). No difference was observed in the concentrations of DA and DOPAC in the vitreous of people without diabetes compared to those with diabetes without retinopathy.

EFFECT OF LUBRICANTS ON CORNEAL THICKNESS AFTER VITRECTOMY.

PURPOSE: This study examines the impact of corneal surface lubricants used during pars plana vitrectomy on corneal edema. METHODS: This prospective, observational, clinical study occurred at an academic institution. Participants were individuals aged 18 years and older who had already consented to undergo pars plana vitrectomy, without pre-existing corneal pathology. A corneal lubricant was chosen by the surgeon. Corneal thickness was measured preoperatively and postoperatively using pachymetry and anterior segment optical coherence tomography (AS-OCT). Main outcome measure was change in corneal thickness as measured by pachymetry. RESULTS: Forty-one patients completed the study protocol. The 23 subjects in the SHCS group had a significantly smaller increase in corneal thickness as measured by pachymetry compared with the 18 subjects in the HPMC group (29.9 µm vs. 58.1 µm, P value 0.02). When measured by anterior segment optical coherence tomography, the SHCS group had a smaller increase in corneal thickness compared with the HPMC group (0.04 mm vs. 0.06 mm, P value 0.09) but did not reach significance. CONCLUSION: SHCS is associated with reduced postoperative increase in corneal pachymetry as compared to HPMC.

Using a Deep Learning Algorithm and Integrated Gradients Explanation to Assist Grading for Diabetic Retinopathy.

PURPOSE: To understand the impact of deep learning diabetic retinopathy (DR) algorithms on physician readers in computer-assisted settings. DESIGN: Evaluation of diagnostic technology. PARTICIPANTS: One thousand seven hundred ninety-six retinal fundus images from 1612 diabetic patients. METHODS: Ten ophthalmologists (5 general ophthalmologists, 4 retina specialists, 1 retina fellow) read images for DR severity based on the International Clinical Diabetic Retinopathy disease severity scale in each of 3 conditions: unassisted, grades only, or grades plus heatmap. Grades-only assistance comprised a histogram of DR predictions (grades) from a trained deep-learning model. For grades plus heatmap, we additionally showed explanatory heatmaps. MAIN OUTCOME MEASURES: For each experiment arm, we computed sensitivity and specificity of each reader and the algorithm for different levels of DR severity against an adjudicated reference standard. We also measured accuracy (exact 5-class level agreement and Cohen's quadratically weighted κ), reader-reported confidence (5-point Likert scale), and grading time. RESULTS: Readers graded more accurately with model assistance than without for the grades-only condition (P < 0.001). Grades plus heatmaps improved accuracy for patients with DR (P < 0.001), but reduced accuracy for patients without DR (P = 0.006). Both forms of assistance increased readers' sensitivity moderate-or-worse DR: unassisted: mean, 79.4% [95% confidence interval (CI), 72.3%-86.5%]; grades only: mean, 87.5% [95% CI, 85.1%-89.9%]; grades plus heatmap: mean, 88.7% [95% CI, 84.9%-92.5%] without a corresponding drop in specificity (unassisted: mean, 96.6% [95% CI, 95.9%-97.4%]; grades only: mean, 96.1% [95% CI, 95.5%-96.7%]; grades plus heatmap: mean, 95.5% [95% CI, 94.8%-96.1%]). Algorithmic assistance increased the accuracy of retina specialists above that of the unassisted reader or model alone; and increased grading confidence and grading time across all readers. For most cases, grades plus heatmap was only as effective as grades only. Over the course of the experiment, grading time decreased across all conditions, although most sharply for grades plus heatmap. CONCLUSIONS: Deep learning algorithms can improve the accuracy of, and confidence in, DR diagnosis in an assisted read setting. They also may increase grading time, although these effects may be ameliorated with experience.

Amygdala real-time fMRI neurofeedback upregulation in treatment resistant depression: Proof of concept and dose determination.

Previous work has shown that adults suffering from major depressive disorder (MDD) can increase their amygdala reactivity while recalling positive memories via real-time neurofeedback (rt-fMRI-nf) training, which is associated with reduction in depressive symptoms. This study investigated if this intervention could also be considered for patients suffering from MDD who do not respond to standard psychological and pharmacological interventions, i.e., treatment resistant (TR-MDD). 15 participants received 5 neurofeedback sessions. Outcome measures were depressive symptoms assessed by BDI scores up to 12 weeks following acute intervention, and amygdala activity changes from initial baseline to final transfer run during neurofeedback sessions (neurofeedback success). Participants succeeded in increasing their amygdala activity. A main effect of visit on BDI scores indicated a significant reduction in depressive symptomatology. Percent signal change in the amygdala showed a learning curve during the first session only. Neurofeedback success computed by session was significantly positive only during the second session. When examining the baseline amygdala response, baseline activity stabilized/asymptoted by session 3. This proof-of-concept study suggests that only two neurofeedback sessions are necessary to enable those patients to upregulate their amygdala activity, warranting a future RCT. Over the course of the rtfMRI-nf intervention, participants also reported reduced depressive symptomatology. Clinical trial registration number: NCT03428828 on ClinicalTrials.gov.

Recall of Autobiographical Memories Following Odor vs Verbal Cues Among Adults With Major Depressive Disorder.

Importance: Major depressive disorder (MDD) is associated with deficits in autobiographical memory (AM) recall, which is thought to stem from disruptions in effortful recall. Understanding whether these deficits are mitigated when recall is stimulated more directly, such as by odor cues, could inform therapeutic interventions for MDD. Objective: To evaluate whether deficits in specific AM recall in MDD are mitigated when odor cues vs word cues are used to prompt memory. Design, Setting, and Participants: This cross-sectional study assessed recall of specific AMs in response to both odor cues and word cues (in a randomized, counterbalanced order) in a repeated measures design. Data were collected between September 2021 and November 2022. The study took place at the University of Pittsburgh School of Medicine in Pennsylvania and included adults with a primary diagnosis of MDD, according to the Mini International Neuropsychiatric Interview. Data were analyzed from January to June 2023. Main Outcomes and Measures: The primary outcome measure was the percentage of specific AMs recalled in response to odor-cued memories vs word-cued memories. Additional outcome measures included ratings of arousal, vividness, repetition, and recall response time for odor-cued memories vs word-cued memories. Results: Thirty-two adults (mean [SD] age, 30.0 [10.1] years; 26 [81.3%] female; 6 [18.8%] male) with a primary diagnosis of MDD completed the study. Participants recalled more specific AMs for odor cues than word cues (mean [SD], 68.4% [20.4%] vs 52.1% [23.3%]; Cohen d, 0.78; P < .001). Additionally, odor-cued recall was rated more arousing (mean [SD], 3.0 [0.8] vs 2.6 [0.7]; Cohen d, 1.28; P < .001) and vivid (mean [SD], 3.3 [0.7] vs 3.0 [0.7]; Cohen d, 0.67; P < .001), and was slower than word-cued recall (mean [SD], 14.5 [3.6] vs 8.9 [3.4] seconds; Cohen d, 1.18; P < .001). When compared with the population mean for word cues in healthy controls (80%), participants recalled fewer specific memories in response to words (Cohen d, 1.18; P < .001), supporting the presence of overgenerality. Notably, the percentage of specific memories recalled in response to odor cues did not differ from the healthy control population mean (Cohen d, 0.26; P = .15). Conclusions and Relevance: In this cross-sectional study, adults with MDD recalled more specific AMs in response to odor cues compared with word cues. This study suggests that AM deficits may only be observed when verbal cues are used and provides a potential new method for increasing specific AM recall in patients with MDD.

Enhanced efficacy of CBT following augmentation with amygdala rtfMRI neurofeedback in depression.

BACKGROUND: Despite cognitive behavioral therapy (CBT) being a standard treatment in major depressive disorder (MDD), nearly half of patients do not respond. As one of the predictors of CBT's efficacy is amygdala reactivity to positive information, which is often decreased in MDD, we explored whether real-time fMRI neurofeedback (rtfMRI-nf) training to increase amygdala responses during positive memory recall prior CBT would enhance its efficacy. METHODS: In a double-blind, placebo controlled, randomized clinical trial, 35 adults with MDD received two sessions of rtfMRI-nf training to increase their amygdala (experimental group, n = 16) or parietal (control group, n = 19) responses during positive memory neurofeedback prior to receiving 10 CBT sessions. Depressive symptomatology was monitored between the rtfMRI sessions, the first three, 9th and 10th sessions of CBT and at 6 months and 1 year follow-up. RESULTS: Participants in the experimental group showed decreased depressive symptomatology and higher remission rates at 6 months and 1 year follow-up than the control group. Analysis of CBT content highlighted that participants in the experimental group focused more on positive thinking and behaviors than the control group. LIMITATIONS: The study was relatively small and not sufficiently powered to detect small effects. CONCLUSIONS: CBT, when combined with amygdala neurofeedback, results in sustained clinical changes and leads to long-lasting clinical improvement, potentially by increasing focus on positive memories and cognitions.

Effect of Age at Primary Intraocular Lens Implantation on Refractive Growth in Young Children.

PURPOSE: To evaluate the effect of age at primary intraocular lens (IOL) implantation on rate of refractive growth (RRG3) during childhood. METHODS: A retrospective chart review was performed for children undergoing primary IOL implantation during cataract surgery. RRG3 was calculated for one eye from each patient using the first postoperative refraction, last refraction that remained stable (< 1.00 diopters [D] change/2 years), and the corresponding ages. RRG3 values for pseudophakic patients operated on from ages 0 to 5 months were compared with values for patients operated on at ages 6 to 23 months and 24 to 72 months. Patients with refractive errors that stabilized were grouped by age at surgery to compare age at refractive plateau. RESULTS: Of 296 eyes identified from 219 patients, 46 eyes met the inclusion criteria. There was a statistically significant difference in RRG3 among age groups. The mean RRG3 value was -19.82 ± 5.23 D for the 0 to 5 months group, -22.32 ± 7.45 D for the 6 to 23 months group (0 to 5 months vs 6 to 23 months, P = .43), and -9.64 ± 11.95 D for the 24 to 72 months group (0 to 5 months vs 24 to 72 months, P = .01). CONCLUSIONS: Age at primary IOL implantation affects the RRG3, especially for children 0 to 23 months old at surgery. Surgeons performing primary IOL implantation in infants may want to use age-adjusted assumptions, because faster refractive growth rates can be expected in young children. [J Pediatr Ophthalmol Strabismus. 2020;57(4):264-270.].

Characteristics and Outcomes of Endogenous Endophthalmitis: Eight-Year Experience at a Tertiary Care Center.

PURPOSE: To describe the characteristics and outcomes of endogenous endophthalmitis. DESIGN: Retrospective case series. PARTICIPANTS: Patients with endogenous endophthalmitis. METHODS: A retrospective chart review of patients diagnosed with endogenous endophthalmitis between September 1, 2006, and November 1, 2014. MAIN OUTCOME MEASURES: Clinical findings, treatments, microbial results, visual outcomes, and secondary ocular sequelae. RESULTS: Sixty-three patients (68 eyes) were diagnosed with endogenous endophthalmitis. Ocular symptoms were the first manifestation of disease in 76% of patients. Fungal and bacterial endophthalmitis were seen in 37% (n = 25) and 43% (n = 29) of eyes, respectively. In 47% of eyes (n = 32), the disease was associated with intravenous drug use. Eighteen percent of eyes (n = 12) underwent an initial pars plana vitrectomy (PPV) with intravitreal antibiotics, none of which required a secondary intervention for acute infection. Four percent of eyes (n = 3) received only systemic treatment. Seventy-eight percent of eyes (n = 53) underwent initial bedside aspirate with intravitreal injection of antibiotics (tap-and-injection), of which 55% (n = 29) required a secondary PPV. Of eyes that underwent secondary PPV after initially negative culture results from the tap-and-injection, 52% demonstrated positive culture results at the time of secondary PPV (n = 11/21) despite all but 1 having received appropriate antimicrobial coverage initially. Fifty-four percent of eyes (n = 37) experienced secondary ocular sequelae. Eyes that received initial tap-and-injection had statistically nonsignificant better average initial vision, but worse average vision at each follow-up interval, compared to PPV while being less likely to gain 2 lines or more of vision at every follow-up interval except 6 months, with the difference reaching statistical significance at 1 week (odds ratio = 0.014; P = 0.037). Eyes that underwent initial tap-and-injection were statistically significantly more likely to require a secondary PPV (55% vs. 0%; P = 0.0006) and had fewer positive microbial results (19% vs. 67%) than those that underwent initial PPV (P = 0.002). CONCLUSIONS: Most eyes that received initial tap-and-injection eventually underwent a secondary PPV. Initial PPV may have an important role in management because it was associated with better diagnostic yield and a trend toward better visual outcomes.

Linguistic analysis of the autobiographical memories of individuals with major depressive disorder.

BACKGROUND: Major depressive disorder (MDD) is characterized by biases in memory, attention, and cognition. The present study utilized the Linguistic Inquiry and Word Count (LIWC) to examine the content of specific autobiographical memories (AMs) recalled by individuals with MDD during an autobiographical memory task. METHODS: We examined various features of the text (including use of affective, cognitive, and self-referential terms), as well as their associations with clinical and cognitive features of MDD (depression severity, autobiographical memory specificity, amygdala activity), in 45 unmedicated adults with MDD compared to 61 healthy controls. RESULTS: When recalling positive memories MDD individuals used the word "I" less, fewer positive words, more words indicating present focus (present tense verbs), and fewer words overall to describe memories compared to controls. When recalling negative memories, MDD individuals used "I" more, more words indicating present focus, and more words overall to describe memories relative to controls. Depression severity was correlated with word count, the use of "I", and words indicating present focus in negative memories and inversely correlated with word count and the use of "I" in positive memories. Autobiographical memory specificity was correlated with word count, the use of "I", and words indicating present focus for positive memories and inversely correlated with the use of "I" and words indicating present focus for negative memories. LIMITATIONS: Due to the nature of AM recall, we could not control for the number of memories which participants recalled in each mnemonic category. CONCLUSIONS: Results align with literature implicating rumination and intensive self-focus in depression and suggest that interventions targeting specific word use may be therapeutically beneficial in the treatment of MDD.

Fronto-Limbic Brain Dysfunction during the Regulation of Emotion in Schizophrenia.

Schizophrenia is characterized by significant and widespread impairments in the regulation of emotion. Evidence is only recently emerging regarding the neural basis of these emotion regulation impairments, and few studies have focused on the regulation of emotion during effortful cognitive processing. To examine the neural correlates of deficits in effortful emotion regulation, schizophrenia outpatients (N = 20) and age- and gender-matched healthy volunteers (N = 20) completed an emotional faces n-back task to assess the voluntary attentional control subprocess of emotion regulation during functional magnetic resonance imaging. Behavioral measures of emotional intelligence and emotion perception were administered to examine brain-behavior relationships with emotion processing outcomes. Results indicated that patients with schizophrenia demonstrated significantly greater activation in the bilateral striatum, ventromedial prefrontal, and right orbitofrontal cortices during the effortful regulation of positive emotional stimuli, and reduced activity in these same regions when regulating negative emotional information. The opposite pattern of results was observed in healthy individuals. Greater fronto-striatal response to positive emotional distractors was significantly associated with deficits in facial emotion recognition. These findings indicate that abnormalities in striatal and prefrontal cortical systems may be related to deficits in the effortful emotion regulatory process of attentional control in schizophrenia, and may significantly contribute to emotion processing deficits in the disorder.

Differential sensory fMRI signatures in autism and schizophrenia: Analysis of amplitude and trial-to-trial variability.

Autism and schizophrenia share multiple phenotypic and genotypic markers, and there is ongoing debate regarding the relationship of these two disorders. To examine whether cortical dynamics are similar across these disorders, we directly compared fMRI responses to visual, somatosensory and auditory stimuli in adults with autism (N=15), with schizophrenia (N=15), and matched controls (N=15). All participants completed a one-back letter detection task presented at fixation (to control attention) while task-irrelevant sensory stimulation was delivered to the different modalities. We focused specifically on the response amplitudes and the variability in sensory fMRI responses of the two groups, given the evidence of greater trial-to-trial variability in adults with autism. Both autism and schizophrenia individuals showed weaker signal-to-noise ratios (SNR) in sensory-evoked responses compared to controls (d>0.42), but for different reasons. For the autism group, the fMRI response amplitudes were indistinguishable from controls but were more variable trial-to-trial (d=0.47). For the schizophrenia group, response amplitudes were smaller compared to autism (d=0.44) and control groups (d=0.74), but were not significantly more variable (d<0.29). These differential group profiles suggest (1) that greater trial-to-trial variability in cortical responses may be specific to autism and is not a defining characteristic of schizophrenia, and (2) that blunted response amplitudes may be characteristic of schizophrenia. The relationship between the amplitude and the variability of cortical activity might serve as a specific signature differentiating these neurodevelopmental disorders. Identifying the neural basis of these responses and their relationship to the underlying genetic bases may substantially enlighten the understanding of both disorders.

Functional neuroimaging to characterize visual system development in children with retinoblastoma.

PURPOSE: To use functional magnetic resonance imaging (fMRI) and diffusion tensor imaging (DTI) to investigate visual system development in children being treated for retinoblastoma. METHODS: Informed consent was obtained for all participants (N = 42) in this institutional review board-approved study. Participants were imaged with a 1.5-T scanner while under propofol sedation. Diagnostic brain and orbital imaging was followed by investigational functional neuroimaging, which included fMRI during photic stimulation through closed eyelids, to measure functional activation in the visual cortex, and DTI, to evaluate diffusion parameters of white matter tracts in the corpus callosum and the periventricular optic radiations. Analysis included 115 examinations of 39 patients with a median age of 16.4 months and age range from 1.5 to 101.5 months at first evaluation. RESULTS: The blood oxygen level-dependent signal was predominantly negative and located in the anterior visual cortex. Activation was affected by tumor lateralization (unilateral or bilateral), macular involvement, and retinal detachment. Patients who had undergone unilateral enucleation showed cortical dominance corresponding to the projection from the nasal hemiretina in the unaffected eye. Diffusion parameters followed a normal developmental trajectory in the optic radiations and corpus callosum, but variability was greater in the splenium than in the genu of the corpus callosum. CONCLUSIONS: Longitudinal functional neuroimaging demonstrated important effects of disease and treatment. Therefore, fMRI and DTI may be useful for characterizing the impact of retinoblastoma on the developing visual system and improving the prediction of visual outcome in survivors.