Polarization sensitive optical low-coherence reflectometry for blood glucose monitoring in human subjects.

A device based on polarization sensitive optical low-coherence reflectometry is developed to monitor blood glucose levels in human subjects. The device was initially tested with tissue phantom. The measurements with human subjects for various glucose concentration levels are found to be linearly dependent on the ellipticity obtainable from the home-made phase-sensitive optical low-coherence reflectometry device. The linearity obtained between glucose concentration and ellipticity are explained with theoretical calculations using Mie theory. A comparison of results with standard clinical methods establishes the utility of the present device for non-invasive glucose monitoring.

Stimulated emission from the biexciton in a single self-assembled II-VI quantum dot.

Using two-photon excitation, stimulated emission from the biexciton state in a single CdSe/ZnSe quantum dot is observed in a two-pulse configuration. We directly time resolve the emission-absorption characteristics and verify the potential for laser action. By setting the polarization of the stimulation pulse, the recombination path of the biexciton and, by this, the state of the photons emitted in the decay cascade is controlled. We elaborate also the coherent response and address entanglement and disentanglement of the exciton-biexciton system.

Lymphoscintigraphy pre- and post-surgical lymphatic leak repair.

This case report demonstrates the use of lymphoscintigraphy for the localization of a pelvic lymphatic leak. The study was made before and after the operative repair of a lymphatic leak and a marked reduction in the leakage was evident postoperatively. The patient, a 38 year old woman, had a history of adenocarcinoma of the cervix, that was treated by abdominal hysterectomy and pelvic node dissection, and she subsequently developed chylous ascites that required ongoing drainage via a Tenckhoff catheter. This case study illustrates how lymphoscintigraphy aided in the localization of a lymphatic leak and the follow up of surgical repair.

99Tcm-labelled IgG scanning does not predict the distribution of intestinal inflammation in patients with inflammatory bowel disease.

In order to assess the value of 99Tcm-labelled-immunoglobulin G(99Tcm-IgG) in the assessment of the activity and distribution of intestinal inflammation in patients with inflammatory bowel disease (IBD), 99Tcm-IgG scans were performed in 18 patients. Patients were divided clinically into two groups, those with (ten patients) and those without (eight patients), intestinal inflammation. Disease activity and distribution were assessed by 111In-oxine granulocyte scanning and/or histological extent of inflammation at endoscopy or surgery in all patients with IBD and most of those without intestinal inflammation. In the assessment of the presence or absence of inflammation, a sensitivity of 80% and specificity of 87% were achieved. However, when the localization of intestinal inflammation was evaluated, only five of eight true positive scans were concordant with the distribution of intestinal inflammation as determined by other methods. Thus, significant areas of inflammation were missed in five of ten patients with IBD (two false negative, three incorrect localization of inflammation). Although 99Tcm-IgG scanning appears to have moderate sensitivity and acceptable specificity in the detection of intestinal inflammation, it performs poorly in assessing the distribution of inflammation and is, therefore, of little value in the assessment of patients with suspected or proven IBD.

Correlations between cerebral arterial velocities, blood flow, and delayed ischemia after subarachnoid hemorrhage.

BACKGROUND AND PURPOSE: Elevated middle cerebral erythrocyte velocities and tissue hypoperfusion have been correlated with delayed ischemia after subarachnoid hemorrhage, but few studies have compared serial arterial velocities with cerebral blood flow and neurological deficits. METHODS: Serial measurements of middle cerebral velocities, using transcranial Doppler ultrasonography, were performed in 34 patients after subarachnoid hemorrhage and correlated with cerebral blood flow, measured in 20 of the 34 using single-photon emission computed tomography with technetium-99m hexamethylpropylene amine oxime and neurological evidence of delayed ischemia. RESULTS: In 16 patients without delayed ischemia, eight had evidence of vasospasm (greater than 120 cm/sec), but only one of seven had hypoperfusion, suggesting that vasospasm might be more common than hypoperfusion in this group (p = 0.1). In 10 patients with delayed ischemia and a lateralizing deficit, both asymmetrical middle cerebral vasospasm (eight of nine with vasospasm) and hypoperfusion (six of six studied) were concordant with the clinically ischemic hemisphere (p less than 0.05). Vasospasm occurred with nonlateralized delayed ischemia in seven of eight patients and with hypoperfusion in five of six, affecting the anterior cerebral territory in three. CONCLUSIONS: Concordant vasospasm and hypoperfusion were most often present in patients with delayed ischemia and lateralizing neurological deficits. Discordant results reflect inherent limitations and the different levels of the circulation monitored by the two techniques.

Early detection of left ventricular mural thrombi after acute Q wave myocardial infarction using 111In oxine-labelled autologous platelets.

Autologous 111In oxine-labelled platelet scintigraphy was used to detect left ventricular thrombi in 20 patients with anterior and 18 patients with inferior Q wave myocardial infarction within 48-72 h. Left ventricular thrombi were found in 8/20 patients with anterior myocardial infarction and in 1/18 patients with inferior myocardial infarction, giving a total incidence of 24%. Patients with left ventricular thrombi were older (64.3 versus 58.2 years), had higher peak creatinine kinase (CK) levels (4523 versus 2749 IU 1-1), lower ejection fraction (19.5 versus 37.8%, P less than 0.005) and were more likely to have an enlarged left ventricle than those without left ventricular thrombi (87.5 versus 54.5%, P less than 0.001). Left ventricular thrombi were found overlying sites of myocardial infarction in 8 out of 9 patients. Apical left ventricular thrombi were 1.7 times more common than septal left ventricular thrombi. All patients received minidose heparin for prevention of deep venous thrombosis. This technique is complementary to echocardiography and may provide additional information in the difficult cases where the decision about full-dose anticoagulation is in doubt.

A serial study of gastric emptying in anorexia nervosa and bulimia.

To determine the natural history of delayed gastric emptying of solid foods in anorexia nervosa (AN), gastric emptying was assessed by scintigraphy in 20 consecutive inpatients; eight had restrictive AN, ten had both AN and bulimia nervosa (BN), and two BN alone. Initial gastric half-emptying time (HET) exceeded 110 min (the upper limit of normal for the laboratory) in 16; their body mass index ranged from 11.7 to 18.1. HET showed a significant negative correlation with body mass (r = 0.71; p less than 0.001) but not age, duration of illness or use of psychotropic medication. Fourteen patients with prolonged emptying were retested; HET improved in nine of 12 retested at one month (p = 0.0005) but none showed a change in the lag phase of emptying. All four patients retested a further one to two months later achieved a HET less than 110 min. Fourteen patients reached a body mass index of 16.3 during treatment and HET improved to better than 110 min in all but one of these. However, normalisation occurred while body mass was still subnormal (less than 20.3) and with amenorrhea still present. This study shows that delayed gastric emptying in AN improves quite rapidly as feeding recommences; thus the motility disturbance is secondary to restriction in food intake and is not fundamental to the disorder.

Immunolymphoscintigraphy for the detection of lymph node metastases from breast cancer.

The presence of metastases in the regional lymph nodes is the major prognostic factor in breast cancer in the absence of overt distant metastases and is also an important indicator of the need for adjuvant therapy in "early" breast cancer. Currently, the accurate assessment of axillary lymph node status requires axillary dissection which has an associated morbidity. An alternative method of identifying patients who are "node positive" has been developed by means of immunolymphoscintigraphy with s.c. administered radioiodinated monoclonal antibody. The 131I-labeled anti-breast cancer antibody (RCC-1; 400 micrograms) and cold iodine-labeled "blocking" antibody (Ly-2.1; 2 mg which is nonreactive with breast cancer) were injected s.c. into both arms and scintigraphy images were obtained 16-18 h after the injection, using the axilla contralateral to the side of the breast cancer as the control. Studies were reported as positive (and therefore indicative of lymph node metastases) if the amount of background-subtracted radioactive count in the axilla of interest exceeded the normal side by a radio equal to or greater than 1.5:1.0 as assessed by computer analysis. In 38 of 40 patients the findings on scintigraphy were correlated with operative and histopathological findings on the axillary dissection specimen or cytological findings of fine needle aspiration of axillary lymph nodes. In a prospective study of 26 patients, the method is more sensitive (86%) and specific (92%) than preoperative clinical assessment (57% sensitivity, 58% specificity) in the detection of axillary lymph node metastases; and by combining both modalities of assessment, there was an improvement in the sensitivity (100%) but a deterioration in the specificity (50%). There was no significant complication from this essentially outpatient procedure and only 1 of 40 patients developed a human anti-mouse antibody response. This novel and safe method of imaging may become a most useful adjunct in the surgical management of breast cancer.

The detection of axillary lymph node metastases from breast cancer by radiolabelled monoclonal antibodies: a prospective study.

In a prospective study to assess the accuracy of monoclonal immunoscintigraphy for the detection of axillary lymph node metastases in breast cancer, two murine monoclonal antibodies that react with human breast cancer (3E1.2 and RCC-1) were labelled with 131iodine, and the radiolabelled antibody was injected subcutaneously into the interdigital spaces of both hands of 40 patients, 36 of whom had breast cancer and the remaining four of whom had fibroadenoma (the normal, contralateral axilla was used as a control). Of the patients with breast cancer, the findings from the scintigraphy images were correlated with histopathology or cytology of the axillary lymph nodes; images were regarded as positive and hence indicative of lymph node metastases if the amount of background-subtracted radioactive count in axilla on the side of breast cancer exceeded the contralateral normal side by a ratio greater than or equal to 1.5:1.0 as assessed by computer analysis. Using this method, immunoscintigraphy had an overall sensitivity of 33% (23% with 131I-3E1.2 and 50% with 131I-RCC-1) for the detection of lymph node metastases and a specificity of 63% (67% with 131I-3E1.2 and 60% with 131I-RCC-1) with problems of non-specific uptake by presumably normal lymph nodes. The results of immunoscintigraphy obtained with 131I-RCC-1 (IgG) were superior to 131I-3E1.2 (IgM) although the accuracy of immunoscintigraphy using 131I-RCC-1 (56%) was not much better than preoperative clinical assessment (50%). However, there were cases when immunoscintigraphy using radiolabelled antibody (IgM or IgG) detected axillary lymph node metastases not suspected by clinical examination. Thus it appears that while immunoscintigraphy may be a useful adjunct to preoperative clinical assessment and is simple and safe, a major improvement in its accuracy is needed before it can replace axillary dissection and histological examination in the accurate staging of axilla in breast cancer.

Treatment of non-toxic multinodular goiter with radioactive iodine.

Fourteen patients with large non-toxic multinodular goiters were treated with 20 to 100 mCi (740 to 3,700 MBq) of radioactive iodine (iodine-131). In seven, the goiter had recurred after a partial thyroidectomy and four of these had had two operations. Eight had symptoms of respiratory obstruction, two had dysphagia, and the others sought treatment for cosmetic reasons. After administration of iodine-131, there was a significant decrease in goiter size in 11 of the 14 patients, and all those with obstructive symptoms showed improvement. No significant local side effects occurred, but hypothyroidism and Graves' disease each occurred once during follow-up from one to 13 years. Radioactive iodine in doses of 20 to 100 mCi is an effective, safe therapeutic alternative in patients with large non-toxic multinodular goiter, particularly when there is recurrence following surgery or when there are contraindications to surgery.

Uptake of 99mTc pertechnetate in a partial volvulus of the proximal jejunal loop.

High uptake of Technetium-99m Pertechnetate (99mTcO4) in situations unrelated to the presence of acid-secreting gastric cells has attracted recent attention. A 10 year old white girl, investigated for the possible presence of a Meckel's diverticulum, was found to have a partial volvulus of the proximal jejunal loop that exhibited intense localization of Technetium-99m Pertechnetate.

Assessment of bile flow by radioscintigraphy in patients with biliary-type pain after cholecystectomy.

Scintigraphy of the biliary system using 99mTc di-isopropyl iminodiacetic acid (DIDA) was performed in 65 subjects who had previously undergone cholecystectomy. Of the 65 subjects, 20 were free of pain and 45 had biliary-type pain both with (group I) and without (group II) features of sphincter of Oddi dysfunction. This dysfunction comprised dilatation of the bile duct, a transient rise in serum levels of liver enzymes after episodes of pain, or both abnormalities. After computer acquisition of images at intervals of 60 seconds for at least 90 minutes, time/activity curves were generated for five regions of interest: liver, common hepatic duct, common bile duct, duodenum, and background. The time at which counts in the common bile duct reached 50% of maximum (CBD T50) and the time of first entry of isotope into the duodenum (TD) were used to compare asymptomatic subjects with those with biliary-type pain. Patients in group I, but not those in group II, showed significant prolongation of CBD T50 (p less than 0.002) and TD (p less than 0.02) when compared to values in asymptomatic subjects. Six patients had a second scan at six to 12 months after endoscopic sphincterotomy and all showed a reduction in values for CBD T50 and TD. In patients with pain, a significant correlation was shown between bile duct diameter and CBD T50 (p less than 0.01) and between bile duct diameter and TD (p less than 0.02) but results from scintigraphy were independent of responses to morphine-neostigmine and motility in the sphincter of Oddi as assessed by endoscopic manometry.(ABSTRACT TRUNCATED AT 250 WORDS)

Visualization of metastases from colon carcinoma using an iodine 131-radiolabeled monoclonal antibody.

A murine monoclonal antibody that reacts with human colonic cancer (250-30.6) was labeled with radioactive iodine (131I) and the antibody was injected intravenously into 15 patients with known metastases originating from carcinoma of the colon (10 cases), malignant melanoma (1), breast (1), pancreas (1), hepatocellular carcinoma (1), and adenocarcinoma of unknown origin (1). Of the patients with metastatic colon carcinoma, there were 19 known deposits as judged by the techniques of clinical examination, x-rays, and scans obtained using sulpha-colloid. Of these 19 deposits, 17 (90%) were found using the 131I-labeled monoclonal antibody. In one case, the primary tumor, previously undiagnosed, was found. In only 1 of the 10 patients was tumor not found and this was due to the subsequent finding that the undifferentiated tumor did not react with antibody. Of the five patients who did not have carcinoma of the colon, three had negative scans, but two were positive. Thus, the technique of immunoscintography can readily detect both primary and metastatic tumors.

Immunoscintigraphy for detection of lymph node metastases from breast cancer.

A radiolabelled monoclonal antibody that reacts with human breast cancer was injected into the web space of each hand in eight women with breast cancer, and the axillae were scanned 16-24 h later. Scans were positive in seven axillae with palpable lymph nodes and in two axillae with impalpable lymph nodes (metastases later confirmed by needle aspiration). The scan was negative in one axilla with a palpable mass, and here no tumour cells were obtained on needle aspiration. In a man with axillary lymphoma, no specific binding of antibody was observed. This technique could lead to earlier and more precise diagnosis of lymph node metastasis in patients with breast cancer.

Tumour visualisation using a radiolabelled monoclonal antibody.

A radiolabelled monoclonal antibody was injected intravenously into two patients with disseminated carcinoma of the colon and serial scintigrams were then obtained on three consecutive days. In addition to the "specific" antibody image, blood pool and conventional liver scans were also obtained. After computer-based subtraction discrete hepatic metastases could be demonstrated in both patients, while in the second patient, the primary colonic tumour was also visualised for the first time. The study demonstrates the specific localisation of primary and secondary carcinoma of the colon with a radiolabelled monoclonal anti-tumour antibody and offers an improved method of specifically detecting tumours in man.