Characterization of the third-harmonic radiation generated by intense laser self-formed filaments propagating in air.

We perform laboratory experiments to study ultraviolet radiation generated by intense self-formed laser filaments produced by propagating high-power femtosecond laser pulses in air. The laser used in the experiment is a 0.5 TW Ti:sapphire system with the center wavelength at 800 nm. The observed ultraviolet emission occurs in the form of the third harmonic and frequency-upshifted radiation from the fundamental. We present direct characterization of the generated harmonic and frequency-upshifted radiation, including transverse imaging and spatially resolved spectral measurements.

Implementing real-time system interfaces to support the shared care of diabetes patients.

This paper describes a collaborative project: the Medway Integrated Care Support (MEDICS) Project, involving GP and Hospital system suppliers, an NHS Trust, General Practitioners and the NHS Information Authority. The objective of the project is to assess the Object Management Group's (OMG/CORBAMed) Clinical Observations Access Service (COAS) standard, by demonstrating its use in implementing a real-time interface between a GP system and a hospital clinical system, supporting the shared care of diabetes patient.

Three-phase Tc-99m labeled RBC scintigraphy of a splenic hemangioma.

A 46-year-old man presented with right upper quadrant pain with a clinical suspicion of cholelithiasis and was referred for an abdominal ultrasound (US). On US evaluation, the liver and gallbladder were normal. Incidentally noted a homogeneous, well demarcated, hyperechoic, 5-cm mass in the inferior portion of the spleen. A subsequent Tc-99m labeled RBC scan showed a 5-cm photopenic area in the inferior portion of the spleen on perfusion and early blood pool images. Subsequent filling in on delayed images with slightly increased uptake relative to surrounding splenic tissue was seen on the final images (85 min). Splenic hemangiomas are rare neoplasms, although they still represent the most common primary neoplasm of the spleen. The incidence of splenic hemangiomas ranges from 0.03-14% in autopsy studies.

Skeletal scintigraphy with technetium-99m-tetraphenyl porphyrin sulfonate for the detection and determination of osteomyelitis in an animal model.

UNLABELLED: This article explores the accumulation of 99mTc-tetraphenyl porphyrin sulfonate (TPPS4) at inflammatory sites, especially osteomyelitis, and compares the results with 111In Cl3 and 111In-WBC in an animal model. METHODS: Osteomyelitis was induced in 12 New Zealand white rabbits by injecting staphylococcus aureus in the left tibia. Three weeks later, radiographs confirmed the disease. Two hours later, after injection of 74 MBq 99mTc-TPPS4, scintiphotos of the lower extremities were acquired and repeat scintiphotos were obtained 24 hr after injection of 5.55 MBq 111In Cl3. After these studies, 24- and 48-hr scintiphotos of the lower extremities were acquired after injecting 5.55 MBq 111In-labeled WBC. RESULTS: The left tibia averaged three times the uptake with 99mTc-TPPS4 compared with right tibia; with 111In Cl3 and 111In WBC the ratios are two times. These three radiopharmaceuticals reveal positive images, but the image quality using 99mTc-TPPS4 is better, as would be expected from the more favorable physical characteristics of 99mTc and the higher uptake. CONCLUSION: The traditional combination of three-phase bone and 67Ga-citrate scintigraphy can be replaced by a single injection of 99mTc-TPPS4 with imaging as early as 2 hr. Finally, the use 99mTc-TPPS4 should result in a substantial reduction in radiopharmaceutical cost.

Pediatric gastric emptying: value of right lateral and upright positioning.

UNLABELLED: Gastroesophageal reflux and gastric emptying are usually assessed simultaneously with a 1-hr procedure. After ingestion of radiolabeled formula sequential images are gathered when the infant is in the supine position. This position is adequate for gastroesophageal reflux assessment, but delays gastric emptying. METHODS: We studied 48 children, 1 wk to 2 yr of age, who presented with vomiting or failure to thrive. They received 99mTc-sulphur colloid in formula. After completing 1 hr supine imaging we obtained additional abdominal views after changing the position of the infant to right lateral for 30 min, and upright for another 30 min. RESULTS: The percent of gastric emptying at 60 min in the supine position was 35% +/- 19%. After 90 min, in the right lateral decubitus, the percent gastric emptying was 60% +/- 25%. At 120 min, after an upright period, the gastric emptying was 73% +/- 20%. In the supine position 19 of 48 patients showed significant emptying (defined as > 40% emptying). This increased to 41 of 48 normal studies considering the right lateral position and to 45 of 48 normal studies considering the infant upright position. CONCLUSION: Many patients with delayed gastric emptying show significant emptying just by changing position. We routinely complement gastric emptying studies with delayed views in the right lateral and upright position.

Mammoscintigraphy with technetium-99m-sestamibi in suspected breast cancer.

UNLABELLED: Our goal was to determine the clinical usefulness of 99mTc-sestamibi to identify breast cancer in patients prior to biopsy. METHODS: We studied 66 patients who received 20 mCi 99mTc-sestamibi intravenously. Lateral and anterior planar images were gathered within 30 min of the injection. Only focal increased uptake was interpreted as positive. Confirmatory pathologic diagnoses were obtained within 2 mo. The prevalence of breast cancer in our sample was 54%. RESULTS: We report an overall sensitivity of 83% and specificity of 93% for the diagnosis of breast cancer. In palpable lesions, the sensitivity was of 94% with a specificity of 91%, while in nonpalpable abnormalities the sensitivity was of 64% with a 100% specificity. Six patients with a malignancy had negative scans, four of these lesions were nonpalpable. Only two of 31 patients with benign lesions had an abnormal scan. CONCLUSION: Mammoscintigraphy with 99mTc-sestamibi has high specificity and adequate sensitivity for the noninvasive diagnosis of breast carcinomas.

Peritoneoscintigraphy using Tc-99m MAA for diagnosis of diaphragmatic disruptions in trauma patients.

The diagnosis of diaphragmatic disruptions secondary to blunt trauma is difficult because the patients are usually asymptomatic. Delay in recognition of this injury can be life threatening. The presence of previous pulmonary pathology makes the diagnosis even more difficult to establish. In this report, a diaphragmatic tear was diagnosed using intraperitoneal instillation of Tc-99m MAA.