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Common bile duct exploration: the place of laparoscopic choledochotomy.

Since laparoscopic cholecystectomy was introduced, the treatment of choledocholithiasis has been modified. Preoperative endoscopic retrograde cholangiopancreatography (ERCP) has been performed selectively in elderly patients and in those with a strong suspicion of biliary duct stones (jaundice, demonstrated at ultrasound). Intraoperative discovery of common duct stones at cystic duct cholangiography signifies that they must be removed intraoperatively [or postoperatively by ERPC and endoscopic sphincterotomy (ES)]. As ES has a failure rate of 3-23%, laparoscopic common duct exploration emerges as the treatment of choice. Since November 1990, we have performed 59 laparoscopic common bile duct explorations. In our experience, the transcystic technique (18 patients) with choledochoscopy appears easier to perform than with fluoroscopy without choledochoscopy. Since, during our early experience, we encountered some difficulty with the transcystic technique, we elected to evaluate common duct exploration through a choledochotomy (41 patients). The main advantage of this technique is that it provides complete access to the ductal system without damage to the papilla. This procedure seems more difficult to perform than the transcystic technique and can be used when there are contraindications to the latter.

Adult↗

Perforated colonic carcinoma mimicking perforated peptic ulcer: an argument for full exploration of the stomach and duodenum.

Perforated peptic ulcer is one of the commonest types of hollow-viscus perforation. Because many of these ulcers are found at laparotomy to be sealed off, some authors believe it is unnecessary to dissect the surrounding tissue from the presumed site of perforation. A patient with a long history of peptic ulcer disease experienced the sudden onset of signs and symptoms of perforated peptic ulcer. On exploration, the omentum appeared to be densely adherent to the pylorus and duodenum. However, no perforation was found when the omentum was dissected free from the stomach and duodenum. Further exploration revealed a walled-off, perforated carcinoma of the transverse colon adjacent to the mesenteric border. As a result of this experience, the authors emphasize that when the findings at operation do not fit the clinical presentation in a patient with a presumed perforated peptic ulcer, a thorough exploration of the abdominal viscera is mandatory to identify the pathologic process.

Adenocarcinoma↗

Primary common bile duct closure following exploration: an effective alternative to routine biliary drainage.

Primary closure of the common bile duct following exploration has been safely and effectively performed, as advocated by Halsted, provided no evidence of pancreatitis, cholangitis, or ampullary obstruction exists. Using this precedent, the operative management and clinical course of 29 patients undergoing common bile duct exploration (CBDE) for choledocholithiasis from 1986 to 1992 were reviewed. Ten patients had primary closure of the common bile duct (CBD) following choledochotomy and exploration, and 17 patients had t-tube placement. Two patients had CBDE through an enlarged cystic duct that was then ligated. Patients were selected for t-tube placement if they had pancreatitis, ascending cholangitis, evidence of retained stones, or ampullary obstruction. Two patients in this series died. No patient with primary closure of the CBD suffered a biliary complication including retained stones, biliary fistula, pancreatitis, or bile peritonitis. Serious systemic complications were comparable in both groups. The results of this series support the safety of primary common bile duct closure in selected cases.

Cholecystectomy↗

Evaluation of three-dimensional MRI exploration of prolactin-secreting microadenomas.

Over an 8-month period (July 1990-to February 1991), we explored 21 women presenting with a clinical and laboratory profile of prolactin-secreting microadenoma of the pituitary gland. Magnetic resonance imaging (MRI) is undoubtedly the most efficient method to explore microadenomas, especially when carried out in the absence of any treatment. In 8 cases, MRI was performed in the absence of medical treatment and gave a positive result, i.e. always showed a focal lesion. In the remaining 13 cases the patients had been treated before the exploration, and MRI detected a microadenoma in only 4 cases. The duration of treatment and the time elapsed between its withdrawal and the MRI examination did not seem to influence the positivity or negativity of the imaging results. Among the 9 cases where MRI failed to show a focal lesion, the image was normal in 3 cases and displayed an arachnoidocele in 3 cases; the pituitary gland was convex and homogeneous in 1 case and convex and heterogenous in 3 cases, which raised the problem of the effects of bromocriptine on the MRI images. As regards signals, in 5 cases the microadenoma was hyperintense on the spin-echo sequence without contrast injection; it was undetectable on the same sequence in 2 cases. In 4 cases the lesion was contrast-enhanced after gadolinium injection. Using millimetric sections enables small-size adenomas (2.5 x 3 mm) to be visualized.

Adolescent↗

[Exploration of pathological sperm and its fertilizing power].

The exploration of human sperms has considerably progressed during the last few years, side by side with the development of medically assisted procreation techniques. The sperms are explored by a battery of techniques which evaluate their functional state and the expression of their fertilizing power. Sperm count and motility assessment remain the basic examination in the exploration of couples' infertilities but other more sophisticated techniques can be used to evaluate certain stages in the fertilization process, including the recognition by, and attachment of the sperm to the zona pellucida of the oocyte, its penetration into this zone, the fusion of sperm and oocyte membranes and the transformation of the nucleus into a male protonucleus in the cytoplasm of the oocyte. Up to now, however, most of the techniques that evaluate the functional state of the sperm cell have not been predictive, and the only feasible and repeatable means of evaluating the fertilizing power of a semen is fertilization in vitro.

Fertilization↗

Bilateral neck exploration for primary hyperparathyroidism.

Controversy about the operative approach for primary hyperparathyroidism has prompted a review of our operative experience since 1980. We treated 73 patients with primary hyperparathyroidism during this 10-year period, all of whom underwent bilateral neck exploration in which the surgeons attempted to locate all parathyroid tissue. Thirty-eight patients (52%) were found to have a solitary adenoma, while 35 (48%) patients had multiple gland pathology. There were two cases of persistent hypercalcemia because of a synchronous parathyroid hormone-secreting malignancy in one patient and aberrant fifth gland adenoma in the other patient. Without bilateral neck exploration, about one-half of the patients in our series would not have been cured of primary hyperparathyroidism. Because of the high incidence of multiple parathyroid gland involvement, we conclude that thorough bilateral neck exploration must be considered the goal for surgical treatment of primary hyperparathyroidism.

Adenoma↗

[Interstrain differences in extrapolation capacity and exploration of a cruciform maze correlate with various indices of monoamine metabolism in the brain].

C57BL/6J (B6) and CBA mice with normal karyotype and respective substrains carrying robertsonian translocation (fusion) of chromosomes 8 and 17 (Rb) were compared in their ability to extrapolate the direction of stimulus movement disappearing from the field of vision, rearings and hole-poke responses, and exploration strategies in a plus-maze. Rb mice were shown to be superior to normal karyotype groups in extrapolation behaviour. The pattern of interstrain differences in noradrenaline level in the cortex and serotonin turnover indices in the hippocampus correlated with differences in extrapolation ability, while exploration strategies in the plus-maze correlated with differences in dopamine level and its turnover rate in the neocortex and striatum. The data demonstrated that chromosomal rearrangement inducing behavioural differences was accompanied also by discrete neurochemical changes, and that spatial exploration strategies (being probably the constituent of general spatial abilities of mice) were to a large extent independent from extrapolation ability which was regarded as the index of animal reasoning capacity.

Animals↗

Comparison of endoscopic and surgical explorations for perilymphatic fistulas.

A history suggestive of perilymphatic fistula (PLF) often prompts repeated tympanostomies to establish a diagnosis and perform a repair. Two patients having multiple previous explorations for perilymphatic fistulas were reoperated, comparing endoscopic and open surgical methods. A third patient with a history consistent with PLF also underwent dual assessment. Endoscopic exploration of the middle ear was performed through a myringotomy and, immediately after, by elevation of a tympanotomy flap. The endoscopic examinations were thorough yet revealed no evidence of perilymphatic fistula; however, the surgical approaches revealed pooling in the oval windows consistent with perilymphatic fistula. These findings were video documented. Recurrent and primary fistulas may be the result of artifact, such as injected anesthetic agents and transudates introduced during surgical explorations, which may interfere with an accurate diagnosis of perilymphatic fistula. Endoscopy of the middle ear is recommended as one method to minimize errors in diagnosis.

Adult↗

Regional patterns of c-fos mRNA expression in rat hippocampus following exploration of a novel environment versus performance of a well-learned discrimination.

Previous studies using c-fos cRNA in situ hybridization demonstrated a differential involvement of hippocampal subfields CA1 and CA3 in the acquisition of an olfactory discrimination (Hess et al., 1995). The present experiments employed the same method to examine changes in neuronal activity associated with two related behaviors: (1) initial exploration of the training apparatus and (2) performance of a well-learned odor discrimination. Rats in the two groups had similar labeling patterns within hippocampus indicating increased expression in all three major subfields with the greatest effect being in CA1. This pattern of "CA1 dominance" was notably different from that produced during early stages of two-odor discrimination learning in prior experiments. Hippocampal labeling in exploration and performance rats differed in that (1) hybridization was greater in CA1, CA3, and dentate gyrus in the former group and (2) a tendency for labeled cells to occur in clusters was more evident in exploration animals. Levels of c-fos mRNA in olfactory and visual structures were not predictive of expression patterns within hippocampus although labeling in piriform cortex and dentate gyrus was correlated in rats performing a well-practiced discrimination. Moreover, the pattern of hybridization in olfactory bulb was found to be behaviorally dependent. These results, together with those from previous studies, indicate that hippocampus has multiple patterns of regional activation but that one of these is common to very different behavioral circumstances. It is hypothesized that this common pattern emerges whenever the animal responds to distant cues using species-specific or well-learned behaviors and involves coordinated temporal convergence of sensory and septal/brainstem inputs.

Animals↗

Laparoscopic exploration of the common bile duct-report on two cases and literature review.

The optimal management of the common bile duct stone in the era of laparoscopic surgery is not certain. The common policy is selective preoperative endoscopic retrograde cholangio-pancreatography (ERCP) followed by laparoscopic cholecystectomy. When ERCP fails, the common bile duct is explored via open surgery. New techniques of laparoscopic trancystic exploration of the common bile duct and laparoscopic choledochotomy exploration of the common bile duct are now being tried. The results of two case reports are discussed.

Adult↗

Open surgical exploration after failed endopyelotomy: a 12-year perspective.

PURPOSE: Factors that have a role in endopyelotomy failure have not been fully elucidated but are believed to include high grade hydronephrosis and the presence of crossing vessels at the ureteropelvic junction. MATERIALS AND METHODS: We retrospectively analyzed the importance of renal function, hydronephrosis, ureteral stents, surgeon experience and crossing vessels in determining the outcome of endopyelotomy. RESULTS: Of 401 percutaneous antegrade endopyelotomies performed at our medical center during the last 12 years 60 failed and 54 of these patients underwent surgical exploration. Patients with high grade hydronephrosis and poor initial renal function were much less likely to have successful endopyelotomy than those with moderate hydronephrosis or good renal function (success rates 50 versus 96 and 54 versus 92%, respectively, p <0.001). The most common findings at exploration included severe extrinsic fibrosis and intrinsic fibrotic stenosis. Obstructing crossing vessels were present in 13 patients explored, suggesting a possible role in causing failure in only 4% of all endopyelotomy patients. CONCLUSIONS: Patients with high grade hydronephrosis and poor initial renal function are much more likely to experience endopyelotomy failure. Crossing vessels appear to have a less significant role in endopyelotomy failure than has been previously suggested.

Adolescent↗

Ultrasound exploration in the work-up of unexplained fever in the immunocompromized host: preliminary observations.

In immunocompromized hosts, febrile episodes have an unknown origin (FUO) in about fifty per cent of cases. In this preliminary study we evaluated the role of abdominal and pleural ultrasound (US) examination for early detection of infectious sites. US exploration was performed in a cohort of 14 consecutive FUO patients early after fever onset, at patients' bedside, by a hematologist trained in diagnostic ultrasound, and it was repeated at neutrophil recovery. US exploration showed abnormal abdominal findings in 7 and pleural effusion in 3 patients. In all cases but one the abnormality was found at the first US examination. Abdominal and pleural US exploration is a low-cost, easy to use tool for the work-up of FUO in the immunocompromized host that proved to be effective in identifying the infection site in about 50% of patients.

Abdomen↗

An individually tailored intervention for HIV prevention: baseline data from the EXPLORE Study.

OBJECTIVES: We describe the intervention tested in EXPLORE, an HIV prevention trial aimed at men who have sex with men (MSM), and test the empirical basis of the individually tailored intervention. METHODS: Data on participants' self-efficacy, communication skills, social norms, and enjoyment of unprotected anal intercourse were examined in relation to sexual risk. Combinations of these factors, together with alcohol use and noninjection drug use, were also examined. RESULTS: The individual factors examined were associated with sexual risk behavior. The cohort was shown to be heterogeneous in regard to the presence of combinations of these risk-related factors. CONCLUSIONS: Baseline data from the EXPLORE study support the efficacy of the individually tailored intervention used.

Adolescent↗

Exploration of "alternative" and "natural" drugs in dermatology.

OBJECTIVE: To review some of the promising natural remedies within dermatology to explore their potential clinical benefit in supplementing conventional drugs. DATA SOURCES: MEDLINE searches from January 1966 through October 2000 and Science Citation Index searches from January 1974 through October 2000 were conducted. STUDY SELECTION: Primary importance was given to in vivo and in vitro controlled studies, the results of which encourage further exploration. DATA EXTRACTION: The controls used, the statistical approach to analysis, and the validity of the experimental method analyzed were considered particularly important. Data were independently extracted by multiple observers. DATA SYNTHESIS: Natural remedies seem promising in treating a wide variety of dermatologic disorders, including inflammation, phototoxicity, psoriasis, atopic dermatitis, alopecia areata, and poison oak. CONCLUSIONS: The alternative medications presented seem promising, although their true effects are unknown. Many of the presented studies do not allow deduction of clinical effects. Further experimentation must be performed to assess clinical benefit.

Ascorbic Acid↗

A spike in parathyroid hormone during neck exploration may cause a false-negative intraoperative assay result.

HYPOTHESIS: We hypothesize that false-negative results using the rapid intraoperative parathyroid hormone (IOPTH) assay can be caused by spikes in the level of parathyroid hormone that occur during mobilization of the adenoma. DESIGN: Retrospective analysis of a case series. SETTING: University tertiary care center. PATIENTS: Ten consecutive patients with primary hyperparathyroidism. INTERVENTIONS: All patients underwent neck exploration with IOPTH monitoring. Using a sampling protocol described in the literature, IOPTH values were checked at the time of incision, during mobilization of the adenoma, and 10 minutes after resection of the adenoma. MAIN OUTCOME MEASURES: Patients were evaluated for adequate parathyroid tissue excision as determined by IOPTH levels and examination of ipsilateral glands. All patients had normal serum calcium values documented postoperatively. Parathyroid hormone half-life was calculated assuming first-order kinetic decay. RESULTS: Nine patients had an appropriate decline in IOPTH with a mean +/- SD parathyroid hormone half-life of 3.9 +/- 1.08 minutes. Mobilization of the adenoma resulted in a spike in the IOPTH value, with 1 patient's value increasing from a baseline of 95.5 pg/mL (10.1 pmol/L) to 751 pg/mL (79.1 pmol/L). Another patient who was confirmed to have a solitary adenoma had a false-negative postexcision value. A spike in IOPTH that occurred during neck dissection was not detected by the sampling protocol and explains the false-negative value. A literature review revealed that most protocols check baseline values early in the operation and are at risk for false-negative results due to a spike from mobilization of the adenoma. CONCLUSIONS: These data demonstrate that false-negative IOPTH assay findings can result from a spike in parathyroid hormone level during exploration, which may go unrecognized if baseline values are measured during the early stages of mobilization of the adenoma. We have altered our assay protocol and have begun measuring IOPTH at the time of neck incision, at the time the adenoma is completely removed (time zero [t(0)]), and 10 minutes after excision.

Adenoma↗

Parathyroid gland exploration with local anesthesia in elderly and high-risk patients.

The management of symptomatic hyperparathyroidism in elderly and medically compromised patients, who are at risk under general anesthesia, may be safely and effectively accomplished using local anesthesia. Positive localization with ultrasound, thallium 201-technetium Tc 99m subtraction, and computed tomography permit surgical exploration with local anesthesia in one or two stages, or bilaterally in one stage, in selected cases, by employing the surgical lateral approach to parathyroid surgery. Our study of 29 patients selected for this technique affirms the value and the safety of this method, especially as surgical experience has grown and localization studies have improved. During the latter 24 months of our study, 11 (30%) of 36 operations were performed using local anesthesia by one of us. A success rate in ten of 11 cases was achieved, with one patient requiring a second exploration for adenomatous hyperplasia while under local anesthesia.

Aged↗

Exploration of a self-protective strategy in pediatric oncology staff.

Oncology care is considered a stressful occupation. Little is known about the coping strategies oncology staff members use to deal with the stress of their work. The purpose of this study was to determine whether a self-protective strategy found in parents of children with cancer is also present in pediatric oncology staff. To explore this assumption, staff members' ratings were compared with the parents' ratings on the need for support and with the children's ratings on experienced pain. We also explored the characteristics which staff members attribute to the children and the parents. A total of 76 staff members, 84 children with cancer, and their 163 parents participated in the study. Both gender and number of years working in oncology care were positively associated with increased self-protective reactions in staff members. Male staff members rated medical procedures and the pain children experience in general as less painful than did female staff members. Their judgements about experienced pain in general and the lumbar puncture procedure in particular tended to be lower than the children's ratings. Female staff members attributed more positive characteristics to children with cancer and their parents than did male staff members. Staff members with more years of experience in oncology tended to rate all three medical procedures as less painful than those with less years of experience, and they also attributed more positive characteristics to the children. Staff members should be observant to their perceptions of children and parents, especially if their experience increases.

Adaptation, Psychological↗

Exploring the relationship between hypoplasia and odontometric asymmetry in Isola Sacra, an imperial Roman necropolis.

Anthropological studies reporting odontometric asymmetry values or dental enamel hypoplasia frequencies use these markers as a record of physiological perturbations occurring during dental development. While both markers indirectly suggest the amount of relative stress a population might have experienced, a relationship between the two has been explored only recently in the literature. In this study, we address the possibility of such a relationship in two ways. First, Kendall's tau B correlations test the degree of relationship on the level of the individual between hypoplasia presence/absence (P/A) and severity of hypoplasia appearance (PS) data for the anterior dentition and directional (DA) and fluctuating asymmetry (FA) data for concurrently developing molars pairs. Second, an F-test explores between-group (ranked hypoplastic individuals and non-hypoplastic individuals) variance about the mean, expecting the hypoplastic individuals to be more variable. The sample consists of 72 individuals from the Isola Sacra necropolis, which is associated with Portus, the port city of ancient Rome. Results indicated only a very weak predictive relationship between some variables and few significant differences in variation. However, variance follows trends in published literature. Possible explanations for the lack of interaction on the level of the individual include both etiological and genetic susceptibility factors that are significant in and of themselves as they suggest a more complex reading of the hard tissue evidence for stress in archaeological populations.

Dental Enamel Hypoplasia↗