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At least 127 records · Page 7Linked to original sources

A critical reappraisal of a mandatory exploration policy for penetrating wounds of the neck.

Over-all, the results of this review suggest that mandatory exploration for penetrating wounds of the neck may be safely supplanted by selective management. The basis for this conclusion includes: 1, most neck wounds were not associated with significant injury; 2, routine exploration did not obviate the possibility of missed injuries; 3, negative findings at exploration were associated with a number of complications; 4, hospital stay for patients with negative neck exploration results was similar to those with positive exploration findings, and 5, it appears that selective management should not increase the need for special diagnostic studies. Patients with clearly positive clinical findings indicating visceral neck injury should undergo operative exploration. Those with a negative clinical examination should be closely observed. Contrast roentgenographic and other special studies should be reserved for those with equivocal clinical findings or who have a change in clinical status under observation.

Adolescent↗

[Comparative study of the point diameter of dental explorers and the effect of wear on it].

The diameter of dental explorers from three companies have been measured at 10, 20, 40 and 50 microns from the end of the tip, first on new explorers and then again after submitting these explorers to a stimulated wear test of 25 and 150 times. The study has shown that on new explorers Hu-Friedy had the most uniform tip diameter. The tip diameter of explorers from Healthco and Hu-Friedy were finer then Premier's, and Premier explorers seemed to show the least wear.

Dental Caries↗

Time use and physicians' exploration of the reason for the office visit.

BACKGROUND: Patient-centered clinical methods encourage physicians to explore the patient's reasons for the visit. Practitioners worry that this behavior may be inefficient. This study piloted a method to examine how the number of problems managed and time per problem vary with time spent exploring a patient's views. METHODS: Exploration of a patient's views, medical investigation, explanation, and management were mapped against time for a defined agenda from videotapes of eight second-year residents seeing three simulated patients. Performance of three of four tasks defined completion of work on an agendum. Visit length, time per agendum completed, and proportion of agenda completed were compared with time per task using regression methods. RESULTS: Time on exploration correlated with visit length and proportion of agenda completed, but other tasks did not. Time per agendum completed was unrelated to time on exploration. CONCLUSIONS: Visits were longer when more time was spent exploring the patient's reason for the visit because the physician tackled more problems. Time required per problem was not significantly increased. Task/agenda mapping is worth further development to examine differences in comprehensiveness and efficiency among practice styles.

Office Visits↗

[Explorative thoracotomy in patients with bronchogenic carcinoma].

The authors analyse in a retrospective study a group of 31 patients with explorative thoracotomy, which was performed on account of inoperable bronchogenic carcinoma. The causes of inoperability were assessed and the period of survival after explorative thoracotomy was evaluated. From the total number of 496 patients indicated in 1985-1990 for surgery on account of bronchogenic carcinoma 465 pulmonary resections were made and 31 (6.25%) explorative thoracotomies. In all these patients the c TNM and p TNM classification was assessed. Disagreement in the evaluation of these parameters was found in particular in parameter T which was in agreement only in three instances. Conversely agreement was more frequent in parameter cN and pN (n = 18). The most frequent cause of inoperability was penetration of the tumour into the mediastinum (n = 25). Death within 30 days after surgery was not recorded in the group, three patients of 31 survived 5 years after exploration. Explorative thoracotomy did not exert a negative effect on the period of survival which corresponded to the given stage of the disease. Due to improving preoperative examination methods the number of explorative thoracotomies will probably decline in future, but at present it cannot be completely eliminated.

Adult↗

[Role of rectal exploration, suprapubic and transrectal prostatic ultrasonography, and PSA in the diagnosis and follow-up of prostatic carcinoma].

BACKGROUND AND AIM: The aim of this study was to evaluate the advantages and limits of the various examinations, namely rectal exploration, suprapubic and transrectal scan and PSA, used in the diagnosis and follow-up of prostatic carcinoma. METHODS: The study was carried out in 21 cases of histologically confirmed prostatic carcinoma in patients aged between 57 and 82 years old (mean age: 69.5) referred to the authors' attention between January 1990 and August 1993. RESULTS: With regard to the diagnosis, rectal exploration showed a sensitivity of 80.9%, suprapubic scan 95.2%, transrectal scan and PSA 100%. During the follow-up, patients were divided into operated (9) and non-operated (12) groups. Of the 9 patients undergoing radical prostatectomy, 5 showed residual locoregional disease; of the other 4 who had undergone a complete removal of the gland, one subsequently reported local recidivation. In those patients with residual disease, rectal exploration showed a postoperative sensitivity of 20%, nil sensitivity in the case of local recidivation and 100% specificity in successfully operated patients. Suprapubic scan showed a sensitivity of 60% in patients with residual disease, nil sensitivity in the case of local recidivation and 100% specificity in successfully operated patients. Transrectal scan and PSA revealed 100% sensitivity and specificity in all cases. These patients who were not operated owing to the presence of metastases at the time of diagnosis were divided into those who responded to hormone and chemotherapy (3 total responses, 6 partial responses) and patients who did not respond to this type of treatment (3 non-responders). In the cases of total response, all the tests used obtained 100% specificity. Serum levels of PSA were higher than the threshold value owing to the persistence of metastases. In the cases of partial response to treatment, rectal exploration revealed 50% sensitivity, suprapubic scan 83%, and transrectal scan and PSA 100%. Sensitivity to the four methods used was 100% in all non-responders. CONCLUSIONS: From the results obtained it can be affirmed that the diagnosis of prostate pathology should start with rectal exploration and in the event that this method suggests the probable benignity of the lesion, the diagnostic process should conclude with a suprapubic scan. If rectal examination or suprapubic scan reveal a suspected malignancy, it is essential to perform a transrectal scan or PSA assay which has a high level of sensitivity and specificity for values over 10 ng/ml. During follow-up the only tests which show a high level of sensitivity are transrectal scan and PSA, whereas suprapubic scan and rectal exploration are not reliable in view of the high percentage of false negatives observed. The follow-up of those patients who were not operated and responded totally or partially to treatment must be carried out exclusively using transrectal scan and PSA assay. Suprapubic scan enables the evolution of the neoplasia to be followed over time in those patients who did not respond to treatment.

Aged↗

Maximizing outcomes while minimizing exploration in hyperparathyroidism using localization tests.

HYPOTHESIS: Preoperative localization (ultrasonography and scintigraphy) can be used to limit operative exploration in primary hyperparathyroidism while providing a high rate of success. DESIGN: Prospective cohort analysis of 3 types of exploration (1-gland, unilateral, or 4-gland), as directed by localization. RESULTS: In 185 consecutive patients who underwent operations, the final diagnoses were solitary adenoma in 87% and multigland disease in 13%. Ultrasonography (75%) and scintigraphy (83%) demonstrated an enlarged parathyroid gland and, together with operative findings, resulted in 61 1-gland, 63 unilateral, and 61 4-gland explorations, with an initial success rate of 96% and an ultimate success rate of 99%. Limiting exploration resulted in a significant decrease in operative time and hospitalization. CONCLUSION: Localization can limit exploration with success.

Adenoma↗

Endoscopic cholangiography and stone removal prior to cholecystectomy. A more cost-effective approach than operative duct exploration?

Would economic benefit result from performing endoscopic cholangiography and removal of common bile duct stones prior to cholecystectomy in patients who are suspected preoperatively of having choledocholithiasis? In this study, 173 patients had cholecystectomy and 30 (17%) had common bile duct exploration. Records of these patients were reviewed as were those of 31 patients who had only endoscopic cholangiography and endoscopic stone removal. Cost estimates were based on local charges. Cholecystectomy with common bile duct exploration was $6730 more per patient than cholecystectomy alone. Endoscopic cholangiography and endoscopic stone removal was 87% successful in removing duct stones. Had endoscopic cholangiography and endoscopic stone removal been performed preoperatively in patients undergoing cholecystectomy who had suspected choledocholithiasis, 21 of 30 common bile duct explorations could theoretically have been eliminated. This would have saved $85,526 or $2851 per patient undergoing common bile duct exploration. Our analysis suggests that patients who require cholecystectomy and have suspected choledocholithiasis may be treated more cost-effectively by performing endoscopic cholangiography and endoscopic stone removal immediately prior to cholecystectomy than by cholecystectomy and operative common bile duct exploration.

Adolescent↗

Unilateral neck exploration for primary hyperparathyroidism.

The operative approach to primary hyperparathyroidism due to a single adenoma remains controversial. We evaluated our experience with 75 patients presenting with primary hyperparathyroidism between January 1979 and September 1988. Prior to 1985 all patients underwent bilateral exploration. During this period, ultrasonographic localization in 6 patients proved highly accurate. Subsequently, routine preoperative ultrasonographic localization was used and patients were prospectively evaluated for the following: (1) incidence of unilateral exploration, (2) accuracy of ultrasonographic localization, (3) incidence of complications, and (4) operative time. Localization permitted unilateral exploration in 19 of 36 patients, although its accuracy depended on the interest of the radiologist involved. Institution A had an accuracy of 92%, while institution B had an accuracy of only 43%. There were fewer complications with unilateral exploration, and operative time was significantly less. Unilateral exploration based on preoperative ultrasonographic localization is recommended as the initial approach to primary hyperparathyroidism due to a single adenoma.

Adenoma↗

Exploration strategies for hydrothermal deposits.

With unlimited money the most certain strategy for finding most hydrothermal metal deposits would be by drilling to 5000 m at 50 m spacing. However, the cost would far outweigh the benefit of the discoveries. Geological knowledge and exploration techniques may be used to obtain the greatest benefit for minimum cost, and to concentrate human and material resources in the most economic way in areas with the highest probability of discovery. This paper reviews the economic theory of exploration based on expected value, and the application of geological concepts and exploration techniques to exploration for hydrothermal deposits. Exploration techniques for hydrothermal-systems on Mars would include geochemistry and particularly passive geophysical methods.

Alpha Particles↗

Effects of odor familiarity on the development of systematic exploration in the spiny mouse, Acomys cahirinus.

Developmental changes in patterns of exploration by infant spiny mice, Acomys cahirinus are described. These were investigated using an unbaited radial maze and under three odor conditions; that is, animals were tested in the presence of either familiar (own) odors, unfamiliar conspecific odors, or no odors (washed floor). Two hypotheses were tested. The first was based on the results of a pilot study, and was that adult animals would explore the radial maze in a systematic and predictable fashion tending to move from one arm to the next sequentially. It was hypothesized that infants would adopt this sequential strategy only gradually, as they matured. The second hypothesis was that such patterns of exploration would depend upon the olfactory environment; the presence of familiar odors might facilitate systematic patterns of exploration in very young Acomys. The results showed that both adults and juveniles were less likely to move sequentially when tested with no conspecific odor present; sequential patterns of movement were most likely in the presence of unfamiliar odor, however. The only significant change with age in infants was found for animals tested with unfamiliar odors; these animals showed a dramatic increase in sequential behavior between 3 and 7 days of age. Two additional experiments are reported, which investigated the preferences of infant Acomys for unfamiliar conspecific odors, and it was found that very young (about 3 days) animals exhibit a preference for odors derived from unfamiliar conspecific litters, even when tested in the physical presence of their own parents. The results are discussed with reference to the use of olfactory information as directional cues for animals exploring the radial maze.

Age Factors↗

Cervical exploration for primary hyperparathyroidism.

The classical presentation of primary hyperparathyroidism, "moans, bones, groans," is no longer commonly seen since the diagnosis of hypercalcemia is now made much earlier with the routine use of the SMA 12. In the past 8 1/2 years, 85 patients underwent cervical exploration in our institution for primary hyperparathyroidism. There were 34 male and 51 female patients, ranging in age from 18-84 years. The specific symptoms included hypertension in 40 patients, generalized weakness in 25, renal stones in 14, psychiatric problems in 2, and bone changes on X-ray in 4. Forty-one patients were totally asymptomatic. The diagnosis was made mainly on the basis of history, serum calcium and phosphorous levels, parathormone assay, and 24-hour urinary calcium studies. Preoperative localization studies were performed in 38 patients. Thallium technetium subtraction scans, when positive, were very helpful. The surgical approach involved stepwise exploration of both sides of the neck with identification of all four parathyroid glands. In patients with uniglandular pathology (87%), the adenoma was removed with biopsy of at least one normal gland. In multiglandular disease, the abnormal glands were removed. Frozen section was routinely performed to confirm the presence of parathyroid tissue and no attempt was made to pathologically distinguish adenoma from hyperplasia. Two patients had parathyroid carcinoma. In three patients, serum calcium levels did not fall, resulting in an operative success rate of 96%. One patient treated by subtotal parathyroidectomy developed permanent hypoparathyroidism and one other patient developed temporary hypocalcemia. Only a single patient developed vocal cord palsy. Early exploration in patients with primary hyperparathyroidism is indicated. The basic diagnostic workup is sufficient for initial exploration. It is important to distinguish uniglandular from multiglandular pathology after careful bilateral exploration and identification of all four parathyroid glands.

Adenoma↗

The process of exploration in identity formation: the role of style and competence.

This study drew on two approaches to identity formation, each postulating differing but complementary exploration components (style and competence), in an effort to better understand the identity exploration process. The sample for this study (n=215) was socio-demographically diverse with respect to gender, age, ethnicity and setting, with participants drawn from two universities in two different settings (rural residential, and urban non-residential), with differing ethnicities (primarily non-Hispanic White vs. primarily Hispanic) and varying ages. Overall patterns of results revealed by hierarchical regression analyses were consistent with a process model of exploration and with the view that exploration is a multi-dimensional process comprized of multiple components. The findings also provide evidence for the utility of both of the critical constructivist and co-constructivist approaches to identity formation used in this study, and for the validity of the rich clinical/qualitative literature that gave rise to the construct of exploration.

Adolescent↗

Open common bile duct exploration--end of an epoch?

With the advent of laparoscopic cholecystectomy and the impending replacement of open common bile duct exploration, we have reviewed our ten year experience of conventional common bile duct exploration. Open cholecystectomy was performed in 1681 patients and the common bile duct was explored in 325 (19%). Following initial duct exploration, rigid choledo identified residual choledocholithiasis in 58 and periampullary neoplasia in 2 patients. Unexpected retained stones were identified in 3 patients (0.9%). In a further 4 patients, stones which could not be dislodged from the hepatic ducts were confirmed on 10 day T-tube cholangiogram--transduodenal sphincteroplasty had been performed at the time of original surgery in all four. The mortality was 1.9% overall and 1% during the last 5 years. Endoscopic exploration must compare favourably with these data for safe transition to less invasive techniques.

Adult↗

Exploration of the acute scrotum: a retrospective analysis of 100 consecutive cases.

BACKGROUND: Acute scrotal pain is a common urological emergency. Urgent exploration is the standard means of management, as no investigation can confidently exclude torsion of testis from the differential diagnoses. In our department, all patients up to the age of 40 years, presenting with acute scrotal pain undergo emergency scrotal exploration. AIM: This study assesses the outcome of such a policy in one unit. METHODS: The notes of 100 consecutive males who underwent exploration of scrotum have been reviewed. RESULTS: Testicular torsion was diagnosed in 33% of patients, with torsion of the appendix testis being the next most common entity. In the group with testicular torsion 12% required orchidectomy, and all had presented at least 24 hours after the onset of pain. The perioperative morbidity of scrotal exploration was very low. CONCLUSION: These data justify the policy of emergency exploration for all cases of acute scrotal pain up to the age of 40 years.

Acute Disease↗

Colour Doppler ultrasonography replacing surgical exploration for acute scrotum: myth or reality?

BACKGROUND: Traditionally, every patient with an acute scrotum needed surgical exploration for definitive exclusion of testicular torsion. OBJECTIVE: In this study, we aimed to evaluate the improved accuracy in clinical diagnosis with colour Doppler Ultrasonography (US) added to normal clinical assessment. MATERIALS AND METHODS: We retrospectively reviewed 626 patients, who presented with acute scrotal pain between January 1998 and June 2004. Following history and physical examination, the patients either proceeded directly to surgery or underwent US examination. If clinical suspicion of testicular torsion persisted after US, the patients would still undergo scrotal exploration. RESULTS: Of the 294 patients who had routine scrotal exploration without preliminary US, only 23 (7.8%) were found to have testicular torsion. Amongst the 332 cases that had initial US, 9 (2.7%) patients revealed testicular torsion that was confirmed at subsequent surgery. The remaining 323 patients had initial negative US, but 29 were explored eventually on clinical indications. Of these, 4 (1.2% of 323) cases were diagnosed intra-operatively as testicular torsion. None of the remaining 294 patients who were managed conservatively proved to have testicular torsion after a minimum follow-up of 2 weeks. For testicular torsion, US yielded a sensitivity of 69.2% (95% confidence interval =38.9-89.5), specificity of 100% (95% CI=98.5-100), positive predictive value of 100% and negative predictive value of 97.5%. CONCLUSIONS: US has proven to decrease the number of emergency scrotal explorations, length of hospital stay and hence reduce the cost of management of acute scrotum.

Acute Disease↗

Long-term outcome of unilateral parathyroid exploration for primary hyperparathyroidism due to presumed solitary adenoma.

Unilateral cervical exploration for primary hyperparathyroidism (PHPT) remains controversial. Critics of unilateral exploration have argued that this surgical strategy results in an unacceptably large number of patients with persistent or recurrent hypercalcemia following the initial operation due to undetected additional parathyroid pathology on the contralateral, unexplored side of the neck. We have reviewed retrospectively a large cohort of patients who were submitted to scan-directed unilateral cervical exploration for PHPT following dual-isotope subtraction scintigraphy and according to a standard protocol. Between January 1, 1985 and June 30, 1999 a series of 184 patients underwent scan-directed unilateral neck exploration for PHPT. Following the initial operation three individuals (1.6%) demonstrated persistent hypercalcemia. At a mean follow-up of 59 months (range 6-168 months) none of the patients had developed recurrent hypercalcemia. Scan-directed unilateral cervical exploration represents a valid surgical strategy for a significant proportion of patients with PHPT; and in this group of patients it does not lead to an increased incidence of persistent or recurrent hypercalcemia.

Adenoma↗

Retained common-duct stones after open cholecystectomy and duct exploration in children.

A retrospective study was performed of 250 patients with cholelithiasis treated at the Royal Children's Hospital, (RCH) Melbourne, over 25 years by open operation; 32 (12.8%) had proven choledocholithiasis on either preoperative imaging, operative cholangiography (OpCG), or postoperative investigation. A further 3 had underlying congenital biliary abnormalities and were excluded from further study. Thirty-one of the 32 were explored at open operation, 27 after OpCG and 4 on clinical grounds. One retained common-bile-duct (CBD) stone was undetected until the postoperative period (1/250, 0.25%). Seven ducts were not cleared, giving a duct exploration failure rate of 22.6% (7/31). All 8 retained CBD stones were identified in the early postoperative period and managed with a variety of techniques, including endoscopic retrograde cholangio-pancreatography (ERCP). The incidence of retained stones after open CBD exploration was high (22.6%), and can be attributed to difficulties in operative technique dealing with the smaller paediatric CBD. In addition, haemolytic disease seems to induce a propensity for choledocholithiasis. Given the small numbers presenting with cholelithiasis to RCH (10 per year), it is suggested that a selective approach to CBD exploration is appropriate in children. With the increasing use of laparoscopic cholecystectomy in children and the inherent technical difficulties of laparoscopic operative cholangiography, ERCP may offer an alternative solution in dealing with CBD stones rather than open or laparoscopic CBD exploration.

Adolescent↗

Yawning and suppression of exploration induced by dopamine agonists: no relation to extracellular striatal levels of dopamine.

The present study was aimed at testing the hypothesis that yawning and suppression of exploration induced by low doses of dopamine agonists in the rat are caused by a reduction of synaptic dopamine levels. The decrease in extracellular levels of dopamine in the corpus striatum induced by alpha-methyl-p-tyrosine (alpha MPT, 50-200 mg/kg IP), reserpine (2-5 mg/kg SC) and apomorphine (APO, 0.05 mg/kg SC) was measured in microdialysis experiments. Reserpine and alpha MPT reduced the dopamine levels to the same extent as APO. Exploratory behaviour was suppressed by APO, but not by alpha MPT (50 and 100 mg/kg) when tested in a separate experiment. Reserpine (2 mg/kg) suppressed exploration after 4 hr, but not after 3 hr. Changes in extracellular levels of dopamine were tested simultaneously with changes in yawning in another group of rats implanted with guide cannulae for microdialysis probes. There was a discrepancy in the time-course for the induction of yawning as compared to the changes in extracellular dopamine levels after APO (0.05 mg/kg) as well as after pergolide (0.02 mg/kg SC). Yawning appeared before and lasted shorter than the decrease in dopamine. The time-courses for APO-induced suppression of exploration and yawning were similar. The dose-response curve for APO-induced yawning was not changed by alpha MPT (200 mg/kg), while the suppression of exploration induced by APO, but not by pergolide, was enhanced by pretreatment with alpha MPT. The results show that yawning and suppression of exploration induced by dopamine agonists are not related to changes in extracellular levels of dopamine. It is proposed that these behaviours may be mediated by postsynaptic receptors.

Animals↗