Structural and functional neuroimaging methods in the diagnosis of dementias: a retrospective chart and brain imaging review.

OBJECTIVE: Assess the contribution of structural and functional neuroimaging methods to the diagnosis of dementia. METHODS: This was a retrospective chart and imaging review. Participants were 24 inpatient dementia cases from a general hospital-based, university medical psychiatry unit. Data from clinical charts and imaging results were reviewed. RESULTS: Most common initial diagnoses were dementia NOS and vascular dementia (VD); most common discharge diagnoses were VD, Alzheimer's, Dementia NOS and dementia with Lewy bodies. Most diagnostic changes occurred following family meetings or SPECT/PET, with fewer changes after CT/MRI. CONCLUSIONS: Diagnostic steps that contributed the most to the final diagnosis were the family meeting and the functional neuroimaging evaluation.

Neuroimaging findings and brain-behavioral correlates in a former boxer with chronic traumatic brain injury.

Chronic traumatic brain injury (CTBI) is associated with contact sports such as boxing. CTBI results from repetitive blows to the head rather than from a single impact. CTBI individuals present with motor symptoms (incoordination, spasticity, parkinsonism), cognitive impairment (executive dysfunction, memory deficits) and neuropsychiatric symptoms (irritability, affective disturbances). The structural and functional neuroimaging findings and clinical presentation of a CTBI case are described. We propose hypotheses about the pathophysiology of the observed neuroimaging findings and their relationship to the neuropsychiatric symptoms of the patients.

A study comparing SPECT and MRI in patients with anosmia after traumatic brain injury.

PURPOSE: The initial or first clinical presentation of altered sensation of smell is directly linked to the degree of impaired sensitivity. We took the opportunity to examine normal and nonspecific MRI findings in 6 patients with known anosmia after traumatic brain injury with perfusion SPECT brain imaging. MATERIAL AND METHODS: Patients included those with primary loss of smell after head injury. All patients underwent standard testing by the Taste & Smell Center. Normal or nonspecific near normal brain MRI studies were subsequently referred for SPECT perfusion neuroimaging. RESULTS: MRI studies were negative in 3 cases. In the remaining studies, one case showed nonspecific white matter change, another low signal in the left frontal gyrus, and the sixth case merely some cortical atrophy. All 6 cases demonstrated lesions on SPECT involving the frontal, temporal, and temporoparietal cortex. CONCLUSION: This study identified altered blood perfusion pattern in otherwise normal anatomic structures on MRI.

Radioguided tumorectomy in the management of parathyroid adenomas.

HYPOTHESIS: A clearly localizing sestamibi scan predicts a successful minimally invasive radioguided parathyroidectomy that can be performed with a shorter operative time, low morbidity, and decreased duration of hospital stay. DESIGN: Review of prospectively gathered data and patient medical records. SETTING: Hospitalized care. PATIENTS AND METHODS: Parathyroidectomy was performed on 55 patients with a secure biochemical diagnosis of hyperparathyroidism and a sestamibi scan performed at the University of Connecticut Health Center. Of the 40 patients with a clearly positive sestamibi scan result, 31 underwent radioguided parathyroidectomy. The results of radioguided parathyroidectomy are compared with those of the standard bilateral exploration performed in the remaining 24 patients. MAIN OUTCOME MEASURES: Ionized calcium concentration, postoperative complications, and operative time. RESULTS: All patients were cured of hyperparathyroidism, and no patients experienced recurrent laryngeal nerve damage. Parathyroid adenomas were found at the predicted site in all 40 patients with a clearly localizing sestamibi scan. Of the 31 patients who underwent radioguided parathyroidectomy, a single parathyroid adenoma was identified in 30 patients, and a double adenoma was found in 1 patient. Conversion to a standard procedure was necessary in 1 patient with a large adenoma. The average operating room time was 128 minutes for the radioguided procedure and 224 minutes for the standard exploration. The average incision length for radioguided parathyroidectomy was 3.3 +/- 0.7 cm. CONCLUSIONS: A clearly localizing sestamibi scan predicts that 97% of patients can undergo a successful and safe minimally invasive radioguided parathyroidectomy that requires less operative time than the standard exploration.

Migration of Tc-99m DTPA from the cerebral ventricle to the subarachnoid space.

A 70-year-old woman was examined because of increasing problems with cognition. She had a history of a cerebral shunt placed surgically 10 years previously. Introduction of Tc-99m DTPA directly into the ventricular cavity revealed good ventricular distribution, followed by progression downward, as though into a previous ventriculoperitoneal shunt. However, a chest radiograph revealed what appeared to be a shunt tube in the right atrium. Delayed lateral images showed activity in proximity to the vertebral column, indicating migration of tracer and cerebrospinal fluid into the dorsal and lumbar subarachnoid space.

Ms L: a case of a reversible phenotypic and brain function equivalent of frontotemporal dementia.

Frontotemporal dementia (FTD) is second only to Alzheimer's disease in individuals younger than 65 years of age. Behavioral variant FTD (bvFTD) presents with nonspecific symptoms such as disinhibition, apathy, or emotional blunting. Although neuropsychological testing and structural neuroimaging are not very helpful in diagnosing bvFTD in its initial stages, newer quantitative structural methods and functional neuroimaging have better sensitivity and specificity. Ms L presented with blunted affect, disinhibition, impairments in insight, planning ability and social comportment, changed dietary habits, and episodes of mutism. Her brain magnetic resonance imaging was normal whereas her single-photon emission computed tomography (SPECT) pattern was consistent with FTD. Her clinical presentation was consistent with bvFTD yet both the symptoms and SPECT findings reversed after 2 years of follow-up. We suggest that Ms L had a reversible phenotypic and brain function equivalent of bvFTD. The case highlights the limitations of our diagnostic tools and the complex relationship between clinical symptoms, neuroimaging, and etiology.

SPECT brain imaging in chronic Lyme disease.

OBJECTIVES: Lyme disease is an infectious disease that frequently involves the central nervous system, leading to cognitive and/or mood dysfunction. The basis for these symptoms remains to be defined but may be the result of a vasculitis or metabolic abnormality secondary to the infection. SPECT scans of the brain might provide an objective measure of abnormalities present in patients with otherwise difficult to objectify clinical findings. The objective of this study was to determine the frequency, location, and severity of abnormalities in SPECT scans of the brain of patients with chronic Lyme disease. METHODS: A total of 183 individuals who met the clinical definition of chronic Lyme disease underwent SPECT scanning of the brain using Tc and standard nuclear imagine techniques. Abnormalities of perfusion to affected areas of the brain were defined as mild, moderate, or severe. RESULTS: Of all patients, 75% demonstrated abnormalities in perfusion to various areas of the brain, most notably the frontal, temporal, and parietal lobes. Patients considered to be seropositive and those considered seronegative had similar rates, types, and severity of perfusion defects. Abnormalities of MRI of the brain were seen in 14% of patients. Treatment with antibiotics, especially those with intracellular-penetrating activity, resulted in resolution or improvement of abnormalities in 70% of patients over a 1- to 2-year period. CONCLUSIONS: Brain SPECT scans are abnormal in most patients with chronic Lyme disease, and these scans can be used to provide objective evidence in support of the clinical diagnosis. The use of certain antibiotic regimens seems to provide improvement in both clinical status and SPECT scans.

Potential role of a hybrid intraoperative probe based on OCT and positron detection for ovarian cancer detection and characterization.

Ovarian cancer has the lowest survival rate of the gynecologic cancers because it is predominantly diagnosed in the late stages due to the lack of reliable symptoms and efficacious screening techniques. A novel hybrid intraoperative probe has been developed and evaluated for its potential role in detecting and characterizing ovarian tissue. The hybrid intraoperative dual-modality device consists of multiple scintillating fibers and an optical coherence tomography imaging probe for simultaneously mapping the local activities of (18)F-FDG uptake and imaging of local morphological changes of the ovary. Ten patients were recruited to the study and a total of 18 normal, abnormal and malignant ovaries were evaluated ex vivo using this device. Positron count rates of 7.5/8.8-fold higher were found between malignant and abnormal/normal ovaries. OCT imaging of malignant and abnormal ovaries revealed many detailed morphologic features that could be potentially valuable for evaluating local regions with high metabolic activities and detecting early malignant changes in the ovary. These initial results have demonstrated that our novel hybrid imager has great potential for ovarian cancer detection and characterization during minimally invasive endoscopic procedures.