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Perfusion SPECT scan of Patient B. Arrangement, color scales, and views are identical to Figure 1. Anatomical structures such as the thalamus are positioned similarly to the scan shown in Figure 2. Labeling was eliminated to avoid obscuring the scan details. Perfusion of the thalamus is increased and asymmetrical. Perfusion is markedly increased in the left caudate. Multiple cortical areas of increased perfusion are evident, predominately in the frontal cortices.
Source publication
Bipolar disorder is a significant mental illness affecting over 4 million people in North America and approximately 46 million worldwide. While the onset of bipolar disorder is typically in late adolescence and early adulthood, the correct diagnosis can be delayed for several years. This delay can result in inappropriate pharmaceutical intervention...
Citations
... Youth with a family history of BD often have symptoms of anxiety and mood disorders that may increase their risk for subsequently developing BD. These prodromal symptoms may represent early manifestations of psychopathology that frequently take onset during childhood or adolescence (McLean, Henderson, Pavel, & Cohen, 2022;Singh et al., 2007). The neurobiological characteristics of these youth have been only sparingly described, which may complicate early identification and clinical decision-making about who benefits from treatment or preventive interventions. ...
... In prospective follow-up studies, most relatives do not appear go on to develop BD, so early neurodevelopmental patterns may represent either adaptations or compensatory mechanisms or true risk markers, which may be missed in small sample studies. Multifinality can be partially addressed by studying symptomatic rather than healthy youth at risk for BD (Fischer et al., 2022;McLean et al., 2022). In addition, as image analyses continue to be refined, a network model approach to investigate brain differences in the functional connectome rather than exploratory pair-wise analyses of functional connectivities in individual brain regions may help (Menon, 2011). ...
Background
Youth with a family history of bipolar disorder (BD) may be at increased risk for mood disorders and for developing side effects after antidepressant exposure. The neurobiological basis of these risks remains poorly understood. We aimed to identify biomarkers underlying risk by characterizing abnormalities in the brain connectome of symptomatic youth at familial risk for BD.
Methods
Depressed and/or anxious youth ( n = 119, age = 14.9 ± 1.6 years) with a family history of BD but no prior antidepressant exposure and typically developing controls ( n = 57, age = 14.8 ± 1.7 years) received functional magnetic resonance imaging (fMRI) during an emotional continuous performance task. A generalized psychophysiological interaction (gPPI) analysis was performed to compare their brain connectome patterns, followed by machine learning of topological metrics.
Results
High‐risk youth showed weaker connectivity patterns that were mainly located in the default mode network (DMN) (network weight = 50.1%) relative to controls, and connectivity patterns derived from the visual network (VN) constituted the largest proportion of aberrant stronger pairs (network weight = 54.9%). Global local efficiency ( E local , p = .022) and clustering coefficient ( C p , p = .029) and nodal metrics of the right superior frontal gyrus (SFG) ( E local : p < .001; C p : p = .001) in the high‐risk group were significantly higher than those in healthy subjects, and similar patterns were also found in the left insula (degree: p = .004; betweenness: p = .005; age‐by‐group interaction, p = .038) and right hippocampus (degree: p = .003; betweenness: p = .003). The case–control classifier achieved a cross‐validation accuracy of 78.4%.
Conclusions
Our findings of abnormal connectome organization in the DMN and VN may advance mechanistic understanding of risk for BD. Neuroimaging biomarkers of increased network segregation in the SFG and altered topological centrality in the insula and hippocampus in broader limbic systems may be used to target interventions tailored to mitigate the underlying risk of brain abnormalities in these at‐risk youth.
... The severity of these changes depends on the age and duration of the disease itself [18]. Functional analyzes also show an increase in metabolic activity in the thalamus [19,20]. ...
Bipolar affective disorder is a chronic and complex mood disorder characterized by the combination of manic (bipolar mania), hypomanic and depressive (bipolar depression) episodes. Damage to emotions is dominant, from which damages to other psychological functions arise. The disease is endogenous with a pronounced hereditary factor. Bipolar affective disorder is one of the leading causes of disability worldwide. It is often associated with severe medical and psychiatric comorbidity, early mortality, high levels of functional disability, and compromised quality of life. Contemporary neuropsychiatry aims to recover from illness and enable a person to lead a satisfying life with maximum functionality in the community. The means used for these purposes are pharmacotherapy, psychotherapy and various psychosocial methods that have shown their usefulness in a series of scientific studies. In this paper, we consider the etiology, clinical picture, course, prognosis, as well as available therapies for the treatment of bipolar affective disorder.
... Increased and asymmetric perfusion of the thalamus may serve as a possible endophenotypic pattern of bipolar disorder in the manic or euthymic states (352)(353)(354). Bipolar depression may be similar to unipolar depression in terms of decreased frontal cortex perfusion (355), but it is possible the two can be distinguished by differences in the perfusion of the thalamus and basal ganglia in the depressed state. ...
... Bipolar depression may be similar to unipolar depression in terms of decreased frontal cortex perfusion (355), but it is possible the two can be distinguished by differences in the perfusion of the thalamus and basal ganglia in the depressed state. Perfusion, whether measured by SPECT or fMRI, is increased in the thalamus in bipolar disorder (350,(353)(354)(355)(356)(357). It must be emphasized that these types of endophenotypic patterns may not be evident upon visual inspection of tomographic data for an individual SPECT scan. ...
Brain perfusion single photon emission computed tomography (SPECT) scans were initially developed in 1970's. A key radiopharmaceutical, hexamethylpropyleneamine oxime (HMPAO), was originally approved in 1988, but was unstable. As a result, the quality of SPECT images varied greatly based on technique until 1993, when a method of stabilizing HMPAO was developed. In addition, most SPECT perfusion studies pre-1996 were performed on single-head gamma cameras. In 1996, the Therapeutics and Technology Assessment Subcommittee of the American Academy of Neurology (TTASAAN) issued a report regarding the use of SPECT in the evaluation of neurological disorders. Although the TTASAAN report was published in January 1996, it was approved for publication in October 1994. Consequently, the reported brain SPECT studies relied upon to derive the conclusions of the TTASAAN report largely pre-date the introduction of stabilized HMPAO. While only 12% of the studies on traumatic brain injury (TBI) in the TTASAAN report utilized stable tracers and multi-head cameras, 69 subsequent studies with more than 23,000 subjects describe the utility of perfusion SPECT scans in the evaluation of TBI. Similarly, dementia SPECT imaging has improved. Modern SPECT utilizing multi-headed gamma cameras and quantitative analysis has a sensitivity of 86% and a specificity of 89% for the diagnosis of mild to moderate Alzheimer's disease—comparable to fluorodeoxyglucose positron emission tomography. Advances also have occurred in seizure neuroimaging. Lastly, developments in SPECT imaging of neurotoxicity and neuropsychiatric disorders have been striking. At the 25-year anniversary of the publication of the TTASAAN report, it is time to re-examine the utility of perfusion SPECT brain imaging. Herein, we review studies cited by the TTASAAN report vs. current brain SPECT imaging research literature for the major indications addressed in the report, as well as for emerging indications. In Part II, we elaborate technical aspects of SPECT neuroimaging and discuss scan interpretation for the clinician.
... In the clinical cases presented, we have demonstrated that the optimization of images using a novel set of display tools facilitated the visual interpretation of SPECT imaging data by expert clinicians, without the need for quantification or statistical analysis. A more detailed description of this display will be published shortly (62). ...
The difficulties of evaluating patients with complex neuropsychiatric conditions and prescribing appropriate treatments are well known. Imaging complements clinical assessments and allows a clinician to narrow the differential diagnosis by facilitating accurate and efficient evaluation. This is particularly relevant to neuropsychiatric conditions that are often diagnosed using a trial-and error process of exclusion. Single Photon Emission Computed Tomography (SPECT) is a functional brain imaging procedure that allows practitioners to measure the functional changes of gray matter structures based on regional cerebral blood flow (rCBF). The accurate diagnosis and treatment selection in psychiatry is challenging due to complex cases and frequent comorbidities. However, such complex neuropsychiatric conditions are increasingly benefitting from new treatment approaches, in addition to established medications. Among these are combination transcranial magnetic stimulation with ketamine infusions (CTK), hyperbaric oxygen therapy (HBOT) and perispinal administration of etanercept (PSE). This article provides readers with six case study examples that demonstrate how brain SPECT imaging can be used, both as a diagnostic tool, and as a potential biomarker for monitoring and evaluating novel treatments for patients with complex neuropsychiatric conditions. Six patients were assessed in our clinic and baseline brain SPECT imagesTourettes and a long history of alcohol were visually compared with SPECT images collected after periods of treatment with CTK or HBOT followed by PSE. This retrospective review demonstrates the clinical utility of these novel treatments and describes how SPECT imaging can complement standard diagnostic assessments. A novel display technique for SPECT images is described and we argue that SPECT imaging can be used for monitoring biomarker for clinical change.
Brain perfusion single photon emission computed tomography (SPECT) scans were initially developed in 1970s. A key radiopharmaceutical, hexamethylpropyleneamine oxime (HMPAO), was not stabilized until 1993 and most early SPECT scans were performed on single-head gamma cameras. These early scans were of inferior quality. In 1996, the Therapeutics and Technology Assessment Subcommittee of the American Academy of Neurology (TTASAAN) issued a report regarding the use of SPECT in the evaluation of neurological disorders. This two-part series explores the policies and procedures related to perfusion SPECT functional neuroimaging. In Part I, the comparison between the quality of the SPECT scans and the depth of the data for key neurological and psychiatric indications at the time of the TTASAAN report vs. the intervening 25 years were presented. In Part II, the technical aspects of perfusion SPECT neuroimaging and image processing will be explored. The role of color scales will be reviewed and the process of interpreting a SPECT scan will be presented. Interpretation of a functional brain scans requires not only anatomical knowledge, but also technical understanding on correctly performing a scan, regardless of the scanning modality. Awareness of technical limitations allows the clinician to properly interpret a functional brain scan. With this foundation, four scenarios in which perfusion SPECT neuroimaging, together with other imaging modalities and testing, lead to a narrowing of the differential diagnoses and better treatment. Lastly, recommendations for the revision of current policies and practices are made.
