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PubMed2001

Exploring the utility of demographic data and vaccination history data in the deduplication of immunization registry patient records.

Duplicate patient records pose a major problem for many immunization registries, as well as for many electronic patient record systems. This paper reports two complementary studies exploring the deduplication of immunization registry records. One study explores the utility of different demographic data elements, singly and in combination, to assist in the deduplication process. The second study explores how clinical patient data (vaccination history data) might assist in this process. To assess the utility of demographic data elements, data were used from three registries after duplicates had been identified. A computer program, IMM/Scan, was written to count the number of true-positive (TP) matches and false-positive (FP) matches found when using different Boolean combinations of demographic data elements. In this study, a strategy of "ORing high value ANDed pairs of data elements" appeared to be most powerful. To assess the utility of vaccination history data, record pairs were drawn from 440,000 patient records. Two metrics on patient history were tested: (1) the number of identical doses shared by two records, and (2) the number of "extra" doses in the combined history of two records. In this study, sample findings include: (1) for pairs of nonduplicate records, 93% had no identical doses and 90.6% had "extra" doses, and (2) for pairs of duplicate records, 83.8% had one or more identical doses and 82% contained no "extra" doses. These studies demonstrate potentially useful approaches to using demographic data and patient history data to assist the automated deduplication of immunization patient records.

Demography↗

PubMed1996

Developmental trends in haptic and visual free classifications: influence of stimulus structure and exploration on decisional processes.

This research explores whether the differences observed between the development of visual and haptic free classifications (Berger & Hatwell, 1995) depend from the nature of the information available at different levels of processing. Two experiments are reported, in which subjects were presented with a free classification task using tetrads in the haptic modality (Experiment 1) or in the visual modality (Experiment 2). The type of response elicited (dimensional vs global) was studied as a function of the nature of exploration in Experiment 1 and as a function of the stimulus components' presentation in Experiment 2. Results showed that both the characteristics of exploration and the presentation of the dimensions tended to modify the type to response elicited. The observed modifications, however, were shown to be of different nature in children and in adults. These results were discussed with reference to the development of the valued classification criteria, which could depend on low-level information in young children and on higher-level information in adults.

Adult↗

PubMed1995

Spatial exploration in transgenic mice expressing human beta-S100.

beta-S100 is a calcium-binding protein in the CNS which is involved in the development of the nervous system. In addition, it has been postulated to play a role in long-term potentiation (LTP) in the hippocampus. To test its role in behavior related to hippocampal function, the gene was overexpressed (80 copies) in CD-1 transgenic mice, and the exploration of a novel environment was examined in two experiments. In both experiments subjects' exploratory behavior was observed in an open-field arena containing four objects. No differences in emotional behavior were found between transgenic mice and their controls as measured by the subjects' motility, defecation, and urination. The results of Experiment 1 revealed that transgenic mice explored objects significantly less than the controls, and they did not respond overtly to the spatial change after object displacement. The control CD-1 subjects, on the other hand, showed increased selective reexploration of the displaced object. The results of Experiment 2 replicated the findings of Experiment 1 and revealed more subtle differences in object exploration between the groups. Transgenic mice climbed objects less often and they had longer latencies of object approach than normal CD-1 mice. The study suggests the possible involvement of beta-S100 protein in general exploratory behavior, which includes learning of spatial characteristics of the environment. Specifically, the overexpression of the beta-S100 gene seems to affect the subjects' reactivity to the arousal-inducing properties of novel stimuli.

Animals↗

PubMed1975

Validity of head-dipping as a measure of exploration in a modified hole-board.

To determine whether head-dipping could be validated as a measure of exploration a modified hole-board was developed with four holes in the floor, under which novel objects could be placed. Two criteria for considering head-dipping as a measure of exploration were proposed: firstly that it should reflect novel aspects of the environment; secondly, that exposure to the hole-board should result in information storage. That head-dipping reflected novelty was indicated by the longer duration of head-dips on initial exposure if objects were present, and also on a second exposure when objects were introduced for the first time. Information storage was indicated by habituation on re-exposure to the hole-board. A significant positive correlation between head-dipping in the "four" and "sixteen" hole-boards was obtained for rats, but not for mice. This provided some indirect evidence that rat head-dipping in the "sixteen hole-board" also reflects exploration. (+)Amphetamine and alcohol were tested in the modified hole-board, and (+)amphetamine decreased and alcohol increased the frequency and duration of head-dips.

Animals↗

PubMed1989

Yawning and suppression of exploration in amphetamine-treated rats, incompatibility with the autoreceptor hypothesis.

The hypothesis that yawning and suppression of exploration, induced by low doses of dopamine agonists, are mediated by stimulation of dopamine autoreceptors was tested by studying the influence of amphetamine on these behavioural models and on extracellular levels of dopamine sampled by microdialysis. Behaviour was measured in a holeboard apparatus. A low dose of amphetamine (0.2 mg/kg) caused slight activation of habituated rats. The same dose of amphetamine completely counteracted the decrease in extracellular dopamine levels caused by pergolide (0.02 mg/kg) and, instead, elevated the dopamine levels to 300% above baseline. The same or higher doses of amphetamine (0.5-1.0 mg/kg) did not completely antagonise suppression of exploration or yawning induced by apomorphine (0.05 mg/kg) or pergolide (0.02 mg/kg). The results suggest that both yawning and suppression of exploration induced by low doses of dopamine agonists are not mediated by dopamine autoreceptors, since these behaviours could be elicited when the extracellular levels of dopamine were elevated above baseline. The alternative hypothesis that these behaviours are mediated by sensitive post-synaptic receptors is suggested. It was also found that combined treatment with SCH 23390 (0.05 mg/kg) and amphetamine (2 mg/kg) induced yawning, which further supports the new hypothesis.

Amphetamine↗

PubMed1989

Spontaneous exploration of a 6-arm radial tunnel maze by basal forebrain lesioned rats: effects of the benzodiazepine receptor antagonist beta-carboline ZK 93 426.

Nine days following ibotenic acid induced basal forebrain lesions or a sham-operation, rats were allowed to explore an automated six-arm radial tunnel maze. From each session, several measures of locomotor and exploratory activity were registered. Lesioned and sham-operated animals were treated with either the benzodiazepine receptor antagonist beta-carboline ZK 93 426 (5 mg/kg; IP) or vehicle (Cremofor EL 10% in saline; IP; n = 10 for each group). Treatment was carried out 30 min before each session during acquisition (seven sessions) and reversals of the maze configuration (seven sessions). Eight days following the 14th session, the animals were retested without any further drug treatment. The main results suggest that the lesion resulted in locomotor hyperactivity, an increase in the number of blind arm entries, and of choice stereotypy. Treatment with ZK 93 426 attenuated the lesion-induced alterations of locomotor and exploratory activities. During the retest, the lesioned, previously vehicle-treated rats revisited arms which they had already explored during this session more frequently than the lesioned, previously ZK-treated rats; the latter group did not differ from the sham-lesioned controls. It is concluded that basal forebrain lesioned animals explored the tunnel maze less efficiently than sham-lesioned controls and that the lesioned animals benefited from the treatment with ZK 93 426. Although the specificity of the lesion in terms of destruction of cholinergic neurons remains unsettled, and although the psychological significances of the behavioral measures obtained from the tunnel maze are not yet fully understood, these results suggest that antagonists or partial inverse agonists at the benzodiazepine receptor may be able to normalize basal forebrain lesion-induced behavioral alterations.

Animals↗

PubMed1989

On the selectivity and specificity of the antagonism of apomorphine-induced suppression of exploration by sulpiride.

Ten behavioural variables were recorded by means of an automatic holeboard apparatus. The behaviour of rats placed for the first time in the apparatus was recorded for 10 min. The suppression of this exploratory behaviour by the dopamine agonist apomorphine (0.01-0.1 mg/kg) was shown to be reversible in a surmountable fashion by the dopamine antagonist sulpiride (2 and 4 mg/kg). Suppression of exploration induced by clonidine (0.05-0.2 mg/kg) or diazepam (2 mg/kg) was not antagonised by sulpiride (10 and 50 mg/kg, respectively). The partial dopamine D1-agonist SKF 38393 (2-20 mg/kg) also suppressed exploration but neither sulpiride (20 mg/kg) nor the D1-antagonist SCH 23390 (0.02 mg/kg) could antagonise this effect. The data show that dopamine agonist induced suppression of exploration display pharmacological characteristics of a receptor-mediated response and the data support our previous suggestion that these receptors may be pharmacologically distinct from other dopamine D2-receptors.

2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-ben↗

PubMed1979

Negative exploration for lumbar disc prolapse--findings and possible causes.

32 cases of negative exploration in a joint follow-up series of 3,032 lumbar disc operations are described. Data from 15 hospitals were analyzed by means of questionnaires and computer-aided analysis. Detailed information is given about pre- as well as intraoperative findings. The causes of negative lumbar disc exploration can be divided into two groups. 1. Genuine misdiagnosis where other causes are responsible for the symptoms, and 2. poor technique where despite genuine disc prolapse no evidence was found at operation. The most important causes in the first group were osteochondrotic compression, distended epidural veins, and root tension. The results are less favourable in these patients than in the overall series but, compared to the other complicated courses, the results were markedly better. A review of the literature is given, the possible causes for negative explorations are discussed, and a directive is established for the surgical procedure in cases where an expected prolapse is not found at operation.

Diagnostic Errors↗

PubMedDate not supplied

Causes of failed primary exploration and technical aspects of re-operation in primary hyperparathyroidism.

Hypercalcemia was corrected in 62 (90%) of 69 patients after re-operation for primary hyperparathyroidism during a mean follow-up of 6.3 years. Failed primary exploration was mainly due to inadequate visualization of the pathological parathyroid glands, often in association with misleading or absent peroperative histology. Other causes included seeding of parathyroid adenoma tissue, truly recurrent adenomas, and recurrent hyperplasia, especially in patients with multiple endocrine neoplasia type 1. A considerable number of parathyroid glands missed at the primary operations were subsequently found in essentially normal positions. Ectopic superior glands were most frequently positioned para-esophageally or retro-esophageally, while abnormally placed inferior glands were generally situated within or close to the thymus. Glands in 3 patients were dissected from around the large vessels in the mediastinum. Concomitant thyroid procedures during the primary operation yielded few abnormal parathyroids and made the re-exploration considerably more difficult. We suggest a semilateral approach and caudal identification of the recurrent laryngeal nerve to reduce the hazards of difficult parathyroid re-operations. Mediastinal exploration may require total removal of the thymus and careful dissection of the middle mediastinum.

Adult↗

PubMed1997

Contralateral mastoplasty for breast reconstruction: a good opportunity for glandular exploration and occult carcinomas diagnosis.

BACKGROUND: Exploration of the contralateral breast in case of breast cancer has been advocated by many investigators, based on the incidence of contralateral cancer expected to be around 10-15%. METHOD: From 1978 to 1993, 813 contralateral mammaplasties were performed to obtain symmetry in the course of breast reconstruction, including 373 mastopexies and 440 reduction mammaplasties (RMs). All these operations were performed in patients treated for a cancer of the opposite breast. Clinical and radiologic examination before the reduction mammaplasty showed tissue to be free of evident tumor. RESULTS: Twenty clinically and radiologically occult contralateral cancers were found in the reduction specimen (4.6%). Most of them were located in the lower and central quadrants (70%). The macroscopic size of the tumors varied from 3 to 16 mm. Twelve carcinomas were in situ, and eight cases were infiltrating. CONCLUSION: The symmetry procedure allows a good check-up of the glandular tissue of the contralateral breast at the time of the breast reconstruction, especially when there is no evidence of tumor. The different techniques of breast reduction provide specific possibilities for such exploration and should be chosen according to the preferential area that should be explored.

Adult↗

PubMed1988

Time course of ethanol's effects on locomotor activity, exploration and anxiety in mice.

The time course of the effects of two doses of ethanol on exploration, locomotor activity and anxiety were investigated using the holeboard and plus-maze tests. In an 8 min holeboard test the lower (1.2 g/kg) dose increased both exploration and locomotor activity 0.5 h after ethanol administration whereas the higher (2.4 g/kg) dose decreased exploration but caused an even greater increase in locomotor activity. This activity increase was also seen 1 h post-administration. In the plus-maze test both doses showed an increased number of arm-entries 0.5 h and 1 h after administration but only the 2.4 g/kg dose caused anxiolytic effects persisting for over 2 h. The results add further support to the notion that the behavioral effects of ethanol vary with dose, time of administration and the behavioral measure taken.

Animals↗

PubMed2002

[Intraoperative parathyroid hormone monitoring in neck exploration for renal hyperparathyroidism?].

INTRODUCTION: In operations for renal hyperparathyroidism the value of intraoperative parathormone monitoring was investigated. PATIENTS AND METHODS: Intraoperative intact parathyroid hormone levels were determined (PTH Quick assay) in 40 patients undergoing first cervical exploration and in two patients with graft-dependent recurrence of renal hyperparathyroidism. RESULTS: In 33 patients, total parathyroidectomy with autotransplantation was carried out. The median parathormone levels decreased from 652 pg/ml to 120 pg/ml (19% of initial level) 5 min after total parathyroidectomy. In seven patients, fewer than 4 parathyroid glands each were identified during cervical exploration and "total parathyroidectomy (?)" without autotransplantation was performed. Intraoperatively median parathormone level decreased from 1193 pg/ml to 116 pg/ml (10% of initial level). In one of these seven patients, hyperparathyroidism persisted due to an ectopic fourth gland within the carotid sheath. In two of these patients, hypoparathyroidism occurred and a delayed autotransplantation of cryopreserved parathyroid tissue was carried out. On the first day after total parathyroidectomy with autotransplantation and "total parathyroidectomy (?)", median levels of intact parathyroid hormone were 1.9 pg/ml and 82.5 pg/ml, respectively. CONCLUSION: Intraoperative monitoring is not useful in first cervical exploration for renal hyperparathyroidism because it cannot predict complete resection of parathyroid tissue. The parathormone level on the first postoperative day allows precise evaluation of the efficacy of the surgical procedure.

Chronic Kidney Disease-Mineral and Bone Disorder↗

PubMed2002

Will directed parathyroidectomy utilizing the gamma probe or intraoperative parathyroid hormone assay replace bilateral cervical exploration as the preferred operation for primary hyperparathyroidism?

The trend toward limited exploration for primary hyperparathyroidism (1 degrees HPT) has stemmed from advances in sestamibi scanning, gamma probe technology, and intraoperative parathyroid hormone monitoring (iPTH). Prior to widespread application, directed parathyroidectomy must be shown to meet the high standards of conventional cervical exploration. In this prospective, nonrandomized trial, results of parathyroidectomy utilizing the gamma probe, iPTH, or neither technique were evaluated. Altogether, 150 patients underwent parathyroidectomy utilizing the gamma probe (n = 50), iPTH (n = 50), or neither technique (n = 50). Each group was evaluated for operating time, length of hospitalization, cure rate, morbidity, mortality, and cost. A telephone survey was conducted with 25 patients in each group (n = 75) to address patient satisfaction. The gamma probe localized the abnormal gland in 66% of patients and confirmed cure intraoperatively in 84%. In the iPTH group, a more than 50% decrease from baseline occurred in 98%. The mean operating times were 76, 84, and 90 minutes, respectively (p = 0.16); and the mean length of hospitalization was 1 day. The biochemical cure rates were 98%, 100%, and 96%, respectively (p = 0.17). Total costs were $4476, $3918, and $3905, respectively. A total of 96% of patients in all three groups were "very satisfied" with their surgical procedure. Directed parathyroidectomy utilizing the gamma probe or iPTH assay does not significantly alter the operating time, length of hospitalization, cure rate, morbidity, mortality, or patient satisfaction when compared to conventional exploration in our practice. The probe is more expensive and was not a consistently reliable tool for localizing parathyroid pathology. PTH monitoring reliably predicts cure intraoperatively.

Female↗

PubMed1998

Limited tumor involvement found at multiple endocrine neoplasia type I pancreatic exploration: can it be predicted by preoperative tumor localization?

Radiologically demonstrable pancreatic endocrine tumors are a frequent requirement for exploration in patients with multiple endocrine neoplasia type I (MEN-I). Such delayed intervention is accompanied by a 30% to 50% incidence of pancreatic endocrine metastases. This study explores biochemical tumor markers and operative findings in relation to preoperative pancreatic radiology in 25 MEN-I patients. They underwent pancreatic surgery with (n = 19) or without (n = 6) radiologic signs of primary tumor and absence of metastases upon conventional examination, including OctreoScan testing (n = 10). Biochemical diagnosis required an increasing elevation of at least two independent pancreatic tumor markers. Tumor diameters averaged 1.1 cm (0-5 cm) and 0.9 cm (0.2-1.5 cm) in the patients with and without positive preoperative radiology, respectively. These investigations never displayed more than one of the consistently multiple tumors, and the results were falsely positive in 26%. Preoperatively unidentified regional or hepatic metastases were found at surgical exploration in 26% of patients with radiologic localization and in none of the others. Limited pancreatic tumor involvement necessitated intraoperative absence of metastases and pancreatic lesions </= 1 cm in diameter on palpation, intraoperative ultrasonography, and microscopy. It occurred in 37% and 50% of the patients with and without radiologic tumor localization, respectively. The number of positive tumor markers was similar for patients with limited and major disease (2.3 vs. 2.7), whereas four or more such markers were found in all those with malignancies. The mean marker level was higher in patients with radiologically demonstrable tumors and lower in those with limited disease, but with a substantial overlap. OctreoScan testing was negative in all cases with limited disease and was the single most sensitive method (75%) in the others. Limited pancreatic disease could not be identified preoperatively, and the present means of biochemical pancreatic tumor identification invariably involved the presence of at least one lesion >/= 7 mm in diameter. Conventional pancreatic imaging is insensitive and nonspecific for recognizing even substantial pancreatic tumors associated with MEN-I.

Adult↗

PubMed2006

Prevention of unnecessary contralateral exploration using the silk glove sign (SGS) in pediatric patients with unilateral inguinal hernia.

INTRODUCTION: The issue of how to best detect an occult contralateral patent processus vaginalis (PPV) in a child who presents with a unilateral inguinal hernia has been debated for over 50 years. The ideal diagnostic tool would eliminate unnecessary contralateral exploration. The "silk glove sign" (SGS) or palpating the processus vaginalis over the pubic tubercle is the simplest preoperative diagnostic test for diagnosing contralateral PPV. MATERIALS AND METHODS: In an attempt to determine whether it is possible with the SGS to evaluate the contralateral inguinal region to ascertain if a contralateral PPV is present, we prospectively reviewed our own experience at a single institution within a 5-year period. Between January 2001 and December 2005, 1,040 pediatric patients with inguinal hernias were treated by one surgeon at Chang Gung Children's Hospital. Of these, with the exception of 120 patients with clinical bilateral inguinal hernia, 920 patients (746 boys and 174 girls) with unilateral inguinal hernia underwent examination. A total of 180 (19.8%), of whom 154 were boys and 26 were girls, were SGS positive and underwent bilateral surgery. RESULTS: A PPV or true hernia sac was found in 164 (91.1%). The sensitivity of diagnosis by SGS was 93.1%. In the remaining 740 SGS-negative patients, a metachronous hernia developed in 20. The specificity of diagnosis by SGS was 97.3%. The SGS could detect a contralateral hernia in patients regardless of age, but the accuracy of detection in girls was lower than in boys. CONCLUSION: SGS is a simple, noninvasive method of preoperative evaluation of the groins. Accuracy through repeated and careful examination is about 91%. Our policy of contralateral exploration based on the SGS has been reliable in minimizing unnecessary surgical exploration.

Child↗

PubMed2002

Laparoscopic cholecystectomy and common bile duct exploration are safe for older patients.

BACKGROUND: Laparoscopic common bile duct (CBD) exploration is a well-established treatment option in dedicated centers. However, few data are available on the results in elderly patients. METHODS: The outcome after laparoscopic CBD exploration in elderly patients (age <70 years) was compared with that in a concurrent control group of younger patients (age, <70 years). RESULTS: There were 77 elderly patients in group A and 207 younger patients in group B. American Society of Anesthesiology (ASA) III and IV patients and prior abdominal operations were more frequent in group A (p <0.001). Two patients from each group underwent conversion to open surgery. There was no significant difference frequency of use between the transcystic and choledochotomy approaches, although the latter tended to be more frequent in the group A because of larger stones, (group A 53.4%; group B, 37.6%). Minor and major morbidity (group A, 12%; group B, 13.6%), rate of recurrent stones (group A, 1.3%; group B, 1.9%), and mortality (group A, 1.3%; group B, 0%) were not significantly different between the two groups. The single death in group A involved a patient with acute toxic cholangitis who underwent emergency surgery after multiple failed attempts at endoscopic retrograde cholangiopancreatography/endoscopic sphincterotomy performed elsewhere. No CBD stenosis was observed at follow-up assessment. CONCLUSIONS: Elective laparoscopic CBD exploration is safe and effective. It may become the standard of care in both elderly and younger patients.

Adolescent↗

PubMed2003

Long-term results from laparoscopic common bile duct exploration.

BACKGROUND: The aim of this study was to evaluate the long-term results after laparoscopic common bile duct exploration (LCBDE). METHODS: A retrospective review of 175 consecutive patients who underwent attempted LCBDE between 1992 and 1999 was conducted. Laparoscopic transcystic exploration was accomplished in 110 patients and laparoscopic choledochotomy in 52 patients. Conversion to an open common bile duct exploration was required for 13 patients (7.4%). Retained common bile duct stones occurred in eight patients (4.6%). The 30-day postoperative morbidity was 6.9%, and there was no 30-day mortality. All the patients (alive and localized) received a questionnaire evaluating long-term results. RESULTS: Of the 175 patients, 169 (4 unrelated deaths and 2 patients lost to follow-up evaluation) received and 152 (90%) returned the questionnaire. The follow-up period ranged from 6 to 72 months (median, 36 months). One patient developed recurrent common bile duct stones. There were no signs or evidence of common bile duct stricture in any patient. CONCLUSION: The LCBDE procedure can be performed without increased risk of late bile duct complications.

Abscess↗

PubMed2001

Cost-effective management of common bile duct stones: a decision analysis of the use of endoscopic retrograde cholangiopancreatography (ERCP), intraoperative cholangiography, and laparoscopic bile duct exploration.

BACKGROUND: There are a variety of approaches to the diagnosis and treatment of common bile duct (CBD) stones in patients undergoing laparoscopic cholecystectomy (LC). METHODS: Decision modeling was used to evaluate the cost-effectiveness of four strategies for managing CBD stones around the time of LC: (a) routine preoperative endoscopic retrograde cholangiopancreatography (ERCP) (preoperative ERCP), (b) LC with intraoperative cholangiography (IOC), followed by laparoscopic common bile duct exploration (LCDE), (c) LC with IOC, followed by ERCP (postoperative ERCP), and (d) expectant management (LC without any tests for CBD stones). Local hospital data were used to estimate costs. Cost-effectiveness was expressed in terms of the cost per case of residual CBD stones prevented (in excess of the cost of LC alone). Diagnostic test characteristics, procedure success rates, and adverse event probabilities were derived from a systematic review of the literature. Sensitivity analysis was used to explore the effect of uncertainty on the results of the model. RESULTS: LC alone was the least costly strategy, but it was also the least effective. Of the more aggressive strategies, LCDE and preoperative ERCP were associated with marginal costs of $5993.60 and $299,259.35, respectively, per case of residual CBD stones prevented. Postoperative ERCP was more costly and less effective than LCDE, but it had a lower cost-effectiveness ratio than preoperative ERCP when the prevalence of CBD stones was <80%. CONCLUSIONS: Compared to other common approaches, laparoscopic CBD exploration is a cost-effective method of managing CBD stones in patients who undergo LC. If expertise in LCDE is unavailable, selective postoperative ERCP is preferred over routine preoperative ERCP, unless the probability of CBD stones is very high (>80%).

Cholangiography↗