I-123 iofetamine single-photon computed emission tomography in rapid cycling bipolar disorder: a clinical study.

The regional distribution of I-123 iofetamine (IMP) in the brain of 12 patients with rapid cycling bipolar disorder was studied by single-photon computed emission tomography imaging. Patients who were either medication free (n = 4) or on lithium monotherapy (n = 8) were assessed serially in depressed/dysphoric, manic/hypomanic, or euthymic states. In 23 imaging studies, IMP images of the brain were taken on a GE Starcam system 20 min after injection of 3-4 mCi of I-123 labeled IMP. The I-123 IMP distribution in the anterior part of the temporal lobes was asymmetric in both depression/dysphoria and mania/hypomania but not in euthymia. Images taken sequentially on the same patient showed temporal lobe asymmetry in the pathological mood states that diminished or disappeared in the euthymic state. The observed changes most likely reflect an altered cerebral blood flow and changes in high-affinity IMP binding to amine receptors in the temporal lobes. This pilot study suggests the presence of a state-dependent temporal dysfunction in bipolar disorder.

In vitro and in vivo evaluation of [123I]IBZM: a potential CNS D-2 dopamine receptor imaging agent.

In vitro binding characteristics of a CNS dopamine D-2 receptor imaging agent, (S)-N-[(1-ethyl-2-pyrrolidinyl)] methyl-2-hydroxy-3-iodo-6-methoxybenzamide [( 125I]IBZM), was carried out in rats. Also brain images, as well as organ biodistribution were determined in a monkey following the administration of 123I-labeled compound. The S-(-)-I[125I]IBZM showed high specific dopamine D-2 receptor binding in rat striatum (Kd = 0.426 +/- 0.082 nM, Bmax = 480 +/- 22 fmol/mg of protein). Competition of various ligands for the IBZM binding displayed the following rank order of potency: spiperone greater than S(-)IBZM much greater than R(+)IBZM greater than or equal to S(-)BZM greater than dopamine greater than ketanserin greater than SCH-23390 much greater than propranolol, norepinephrine, serotonin. In vivo planar images of a monkey injected with [123I]IBZM demonstrated a high concentration in basal ganglia of brain. The ratios of activity in the basal ganglia to cerebellum and the cortex to cerebellum in monkey brain were 4.93 and 1.44, respectively, at 120 min postinjection. These preliminary results indicate that [123I]IBZM is a potentially promising imaging agent for the investigation of dopamine D-2 receptors in humans.

The mode of action alginic acid compound in the reduction of gastroesophageal reflux.

This study was designed to evaluate quantitatively the mode of action of alginic acid compound (AAC) in the treatment of patients with symptomatic gastroesophageal reflux. Gastroesophageal scintigraphy using an orall administered Tc-99m sulfur colloid solution was used to demonstrate that AAC decreased significantly the gastroesophageal reflux index from (9.9 +/- 1.3) % to (6.5 +/- 0.8) % (p less than 0.05). No alteration of lower esophageal sphincter pressure was observed. After ACC was suitably labeled with Sr-87m, a dual-nuclide scintigraphic technique was used to show that most (greater than 75%) of the AAC was located in the upper half of the stomach in both normal subjects and patients with gastroesophageal reflux. In those subjects in whom reflux did occur after treatment with AAC, the Sr-87m-AAC refluxed into the esophagus preferentially compared with the liquid containing Tc-99m sulfur colloid. These findings suggest that AAC dimishes gastroesophageal reflux by means of its foaming, floating, and viscous properties.

Myocardial infarct imaging with 99mTc-pyrophosphate and 99mTc-methylene diphosphonate: lack of correlation.

A prospective study of eight patients with recent transmural myocardial infarction was performed using 99mTc-Sn-pyrophosphate and 99mTc-Sn-methylene diphosphonate in each patient. All pyrophosphate scans were strongly positive whereas the diphosphonate scan was strongly positive in only one case. We conclude that 99mTc-Sn-pyrophosphate is preferable to 99mTc-Sn-methylene diphosphonate for myocardial imaging.

A portable survey meter method for locating and quantifying removable contamination after 131I therapies.

Identifying 131I surface contamination and decontaminating the removable fraction from rooms where patients have received iodine therapies is a common task at many hospitals. The current regulatory preferred method for this task is wipe testing for removable contamination. The purpose of this paper is to evaluate the suitability of a sensitive survey meter for this task. Both methods and their detection systems are evaluated in the laboratory as well as in a clinical environment. The results indicate that the portable survey meter method is better at both locating and quantifying removable contamination. An additional benefit of the survey meter method is the ability to clean rooms promptly for reoccupancy.

Virtual real-time digital processing of hemodynamic data.

At present, the majority of cardiac catheterization laboratories acquire and store hemodynamic data in analog form. To examine the possibility of performing complex analysis of digital data during the catheterization procedure, we examined whether virtual real-time digital (fast Fourier) analysis improves the accuracy of clinical data. We compared digital filtering of fluid manometry during the right heart catheterization with 10-Hz and 250-Hz analog filters. Using the simultaneously acquired micromanometry as the "gold standard," we found that analog filtering is associated with a greater error and time delay than digital filtering. This study demonstrates that digital hemodynamic data analysis performed during cardiac catheterization can improve the quality of data obtained during right heart catheterization, with the results available within seconds. More extensive use of computers in the cardiac catheterization laboratory may be useful for both clinical and research purposes.

Esophageal scintigraphy to quantitate esophageal transit (quantitation of esophageal transit).

None of the tests employed currently to investigate esophageal transit is quantitative. The purpose of this study was to evaluate normal subjects and patients with a variety of esophageal disorders using a scintigraphic technique to quantitate esophageal transit. After oral administration of a bolus of water labeled with 99mTc-sulfur colloid, isotopic count rates were measured over the esophagus employing a gamma-camera on line to a digital computer. Esophageal transit was expressed as the percent emptying for each of the first 15-sec after the initial swallow and for 15-sec intervals after serial swallows. Sixty-two subjects were studied, including: normal volunteers; patients with motor disorders of the esophagus such as achalasia, diffuse esophageal spasm, and scleroderma; and patients with symptomatic gastroesophageal reflux both with and without esophageal motor dysfunction on manometic testing. Esophageal transit was decreased significantly after single and multiple swallows in patients with motor disorders of the esophagus. In addition, esophageal transit was abnormal in patients with reflux disease accompanied by abnormal motor function. In contrast, esophageal transit was normal after a single swallow, but incomplete after serial swallows in patients with reflux associated with normal esophageal motor function on manometry. We conclude that esophageal scintigraphy may be used to evaluate esophageal transit.

A diversified patient education program for transplant recipients.

Patients who receive a solid organ transplant not only have many learning needs, but also lifestyle changes related to the transplant. Previous experiences with health care, beliefs about health, language and reading skills, cultural influences, education preparation, and disabilities are a few of the factors that influence how each patient learns posttransplantation, and adjusts to a new lifestyle. Staff nurses on our transplant unit have taken these factors into consideration when developing various concrete teaching tools that include a book, medication card, color-coded medication guide, audiocassette, computer printouts, and clinical pathways. Because each patient comes with a unique story, approaches for patient learning are individualized by the nursing staff. The use of the tools, combined with an individualized and nonjudgmental approach, has created a caring environment for patient learning.