The Emerging Role of SPECT Functional Neuroimaging in Psychiatry & Neurology

Editorial

04 July 2022

Editorial: The Emerging Role of SPECT Functional Neuroimaging in Psychiatry & Neurology

Theodore A. Henderson

Philip F. Cohen

Giuseppe Cardaci

and

Jean-Luc C. Urbain

3,506 views

0 citations

Editors

Theodore A Henderson

Consultant

Joe Cardaci

University of Notre Dame Australia

Philip Frank Cohen

University of British Columbia

Catherine Faget

Assistance Publique Hôpitaux de Marseille

Jean-Luc Urbain

Wake Forest University

Impact

(A) Standard dual-head gamma cameras are too large to get close to the patient's head without hitting the shoulders during rotation. As a result, the field of view of the detector is often poorly utilized with a significant portion of the detector collecting no signal from the brain. (B) CZT detectors are quite small and can be mounted such that the detectors can get very close to the patient's head, maximizing the portion of the field of view occupied by the patient's head. (C) Modern CZT gamma cameras can be configured to withdraw the detectors heads during rotation and then (D) extend the detectors to close proximity of the patient's head during the scanning portion of a step-and-shoot protocol.

Policy and Practice Reviews

17 May 2022

The Legacy of the TTASAAN Report – Premature Conclusions and Forgotten Promises About SPECT Neuroimaging: A Review of Policy and Practice Part II

Dan G. Pavel

, 2 more and

Philip F. Cohen

2,633 views

1 citations

Perfusion SPECT scan of normal control. (A) Horizontal tomograms from a 99m Tc-HMPAO perfusion SPECT scan spanning much of the brain from near superior surface to lower cerebellum (see locator images). (B) Coronal tomograms spanning from anterior margin of cerebellum to anterior cingulate (see locator images). The color scale is scaled relative to the patient’s mean cerebral perfusion. Mean blood flow (72%) is in yellow. Color shifts occur at approximately every 0.5 SD (3%) relative to the patient’s mean. Details of the brain can be appreciated, including the thalamus, head of the caudate nuclei, lentiform nuclei, anterior cingulate gyri, and distinct cortical regions. The perfusion of the thalamus (white with black central dot), right caudate (on the left side of the tomogram), visual cortex and cerebellum are highest in this example. (C) The modern SPECT scan displayed in 3-dimensional reconstruction. Right lateral (RLAT), left lateral (LLAT), Vertex, and underside views are provided. The color scale is the same as panel (B). (D) Isocontour representations of the SPECT data in 3 dimensions. Surface isocontour representations allow visualization of areas of decreased cortical perfusion. Areas in which perfusion falls below 60% of the maximal cerebral blood flow appear as depressions or holes depending on how far below 60% the perfusion falls. Wireframe representations allow visualization of areas of increased perfusion. Areas with perfusion at 85% of the maximal cerebral blood flow appear in green, while areas at 90% of maximal cerebral blood flow appear in red. It is evident that the thalamus, right caudate, cerebellum, and visual cortex are perfused at 90% of maximal cerebral blood flow. This corresponds to what is seen in the tomograms.

Original Research

10 May 2022

Increased Asymmetric Perfusion of the Cerebral Cortices and Thalamus Indicates Individuals at Risk for Bipolar Disorder: A Family Cohort Single Photon Emission Computed Tomography Neuroimaging Study

Mary McLean

, 2 more and

Phil Cohen

5,477 views

4 citations

Original Research

11 April 2022

Using Single-Photon Emission Computerized Tomography on Patients With Positive Quantitative Electroencephalogram to Evaluate Chronic Mild Traumatic Brain Injury With Persistent Symptoms

Alexi Gosset

, 16 more and

Manu Mehdiratta

3,510 views

9 citations

Policy and Practice Reviews

28 March 2022

The Legacy of the TTASAAN Report—Premature Conclusions and Forgotten Promises: A Review of Policy and Practice Part I

Dan G. Pavel

, 1 more and

Simon DeBruin

4,882 views

6 citations

Original Research

25 March 2022

Longitudinal Single Photon Emission Computed Tomography Neuroimaging as an Indication of Improvement in Psychiatric Disorders in a Community Psychiatric Practice

John F. Thornton

, 8 more and

Theodore A. Henderson

2,688 views

3 citations

Original Research

13 January 2022

Brain SPECT as an Imaging Biomarker for Evaluating Effects of Novel Treatments in Psychiatry–A Case Series

Steven R. D. Best

, 1 more and

Dan G. Pavel

5,370 views

5 citations

Surface views (L) and active views (R). Surface views (L) show severe temporal lobe hypoperfusion and active views (R) show severe hyperfrontality. The image on the left shows the outside surface of the brain, looking at the top 45% of brain activity. The image on the right shows the active rendering, where blue equals average perfusion, red is the top 15% of perfusion, and white is the top 8%. A healthy scan shows a symmetrical pattern with the most intense uptake in the cerebellum.

Hypothesis and Theory

10 December 2021

A New Way Forward: How Brain SPECT Imaging Can Improve Outcomes and Transform Mental Health Care Into Brain Health Care

Daniel G. Amen

and

Michael Easton

22,682 views

10 citations

The dopaminergic transmission on synaptic cleft.

Mini Review

15 December 2021

The Emerging Role of SPECT Functional Neuroimaging in Schizophrenia and Depression

Anil Kalyoncu

and

Ali Saffet Gonul

11,562 views

4 citations

A typical example of a control case. Selected tomograms in horizontal (A), sagittal (B), and coronal (C) orientation are provided. The color scale for the tomograms is provided. All voxels are scaled to the brain maximum and assigned each a color gradient based on its percentile of activity. Each color step represents a (not necessarily linear) five-percentile-point change in rCBF. (D) A 3-D representation of the scan data is shown. The surface is set at 60% of brain maximum. Areas which fall below 55% are represented as indentations or holes depending on how far below 55% the activity falls. (E) A wireframe brain representation is shown, wherein the areas of brain with activity at 85% of maximum or greater are shown in red and areas of 92% or greater are shown in white.

Original Research

24 November 2021

SPECT Functional Neuroimaging Distinguishes Adult Attention Deficit Hyperactivity Disorder From Healthy Controls in Big Data Imaging Cohorts

Daniel G. Amen

, 1 more and

Andrew Newberg

Background: The diagnosis of attention deficit hyperactivity disorder (ADHD) relies on history and observation, as no reliable biomarkers have been identified. In this study, we compared a large single diagnosis group of patients with ADHD (combined, inattentive, and hyperactive) to healthy controls using brain perfusion single-photon emission computed tomography (SPECT) imaging to determine specific brain regions which could serve as potential biomarkers to reliably distinguish ADHD.

Methods: In a retrospective analysis, subjects (n = 1,135) were obtained from a large multisite psychiatric database, where resting state (baseline) and on-task SPECT scans were obtained. Only baseline scans were analyzed in the present study. Subjects were separated into two groups – Group 1 (n = 1,006) was composed of patients who only met criteria for ADHD with no comorbid diagnoses, while a control group (n = 129) composed of individuals who did not meet criteria for any psychiatric diagnosis, brain injury, or substance use served as a non-matched control. SPECT regions of interests (ROIs) and visual readings were analyzed using binary logistic regression. Predicted probabilities from this analysis were inputted into a Receiver Operating Characteristic analysis to identify sensitivity, specificity, and accuracy.

Results: The baseline ROIs and visual readings show significant separations from healthy controls. Sensitivity of the visual reads was 100% while specificity was >97%. The sensitivity and specificity of the post-hoc ROI analysis were both 100%. Decreased perfusion was primarily seen in the orbitofrontal cortices, anterior cingulate gyri, areas of the prefrontal cortices, basal ganglia, and temporal lobes. In addition, ROI analysis revealed some unexpected areas with predictive value in distinguishing ADHD, such as cerebellar subregions and portions of the temporal lobes.

Conclusions: Brain perfusion SPECT distinguishes adult ADHD patients without comorbidities from healthy controls. Areas which were highly significantly different from control and thus may serve as biomarkers in baseline SPECT scans included: medial anterior prefrontal cortex, left anterior temporal lobe, and right insular cortex. Future studies of these potential biomarkers in ADHD patients with comorbidities are warranted.

21,695 views

11 citations

Perspective

29 July 2021

Utility of SPECT Functional Neuroimaging of Pain

Mohammed Bermo

, 5 more and

David H. Lewis

Brain perfusion SPECT of dental pain patients receiving analgesia (top row) vs. placebo (bottom row). (A) Asymmetric thalamic activity, more on the right (thin arrow). Post IV ketorolac, the post-interventional scan (B) of the same patient exhibits a slight “switch” in thalamic asymmetry, with mildly greater perfusion on the left (thin arrow). Noted also decreased perfusion in the anterior cingulate region with pain relief [thick arrows in (A) and (B)]. (C) Scan from another patient demonstrating mild asymmetric increased activity in the left thalamus (thin arrow). (D) Same patient with worsening pain after receiving IV placebo, the scan demonstrates more asymmetrically increased perfusion in the left thalamus (thin arrow). Not also increased perfusion in the anterior cingulate cortex compared to (C) (thick arrows). [Images by Newberg et al. (58), reproduced here with permission].

Functional neuroimaging modalities vary in spatial and temporal resolution. One major limitation of most functional neuroimaging modalities is that only neural activation taking place inside the scanner can be imaged. This limitation makes functional neuroimaging in many clinical scenarios extremely difficult or impossible. The most commonly used radiopharmaceutical in Single Photon Emission Tomography (SPECT) functional brain imaging is Technetium 99 m-labeled Ethyl Cysteinate Dimer (ECD). ECD is a lipophilic compound with unique pharmacodynamics. It crosses the blood brain barrier and has high first pass extraction by the neurons proportional to regional brain perfusion at the time of injection. It reaches peak activity in the brain 1 min after injection and is then slowly cleared from the brain following a biexponential mode. This allows for a practical imaging window of 1 or 2 h after injection. In other words, it freezes a snapshot of brain perfusion at the time of injection that is kept and can be imaged later. This unique feature allows for designing functional brain imaging studies that do not require the patient to be inside the scanner at the time of brain activation. Functional brain imaging during severe burn wound care is an example that has been extensively studied using this technique. Not only does SPECT allow for imaging of brain activity under extreme pain conditions in clinical settings, but it also allows for imaging of brain activity modulation in response to analgesic maneuvers whether pharmacologic or non-traditional such as using virtual reality analgesia. Together with its utility in extreme situations, SPECTS is also helpful in investigating brain activation under typical pain conditions such as experimental controlled pain and chronic pain syndromes.

5,101 views

10 citations

Original Research

10 November 2021

Regional Cerebral Blood Flow Abnormalities in Neurosyphilis: A Pilot SPECT Study

Jooyeon J. Im

, 4 more and

Yong-An Chung

2,251 views

10 citations

Original Research

04 February 2021

The Role of Frontal Assessment Battery and Frontal Lobe Single-Photon Emission Computed Tomography in the Differential Diagnosis of Progressive Supranuclear Palsy Variants and Corticobasal Syndrome—A Pilot Study

Piotr Alster

, 8 more and

Andrzej Friedman

Progressive supranuclear palsy (PSP) and corticobasal syndrome (CBS) are clinical syndromes classified as atypical parkinsonism. Due to their overlapping symptomatology, recent research shows the necessity of finding new methods of examination of these clinical entities. PSP is a heterogenic disease. PSP Richardson-Steele Syndrome (PSP-RS) and parkinsonism predominant (PSP-P) are the most common clinical variants of progressive supranuclear palsy syndrome. The different clinical course and life expectancy of PSP-RS and PSP-P stress the need of efficient examination in the early stages. The aim of the study was to evaluate the possible feasibility of the combined use of frontal assessment battery (FAB) and single-photon emission computed tomography (SPECT) in the differentiation of PSP-RS, PSP-P, and CBS. The findings show that FAB may be interpreted as a possible supplementary tool in the differential diagnosis of PSP-P and PSP-RS. The differences in SPECT are less pronounced. The study does not show any advantages of performing combined frontal SPECT and FAB in the differential examination of PSP and CBS. Moreover, PSP-RS and CBS, in a detailed evaluation of the frontal lobe, do not show any significant differences. This is a relatively small study which, however, highlights the relevant features of clinical examination of these rare entities.