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PubMed2000

Changes in exploration from courtship to the breeding state in red-rumped parrots (Psephotus haematonotus).

Animals explore their environment to gather information about feeding areas, resting places, or suitable territories for reproduction. During the annual cycle seasonal variation in exploration occurs at least in some species. In this study, exploratory behaviour of red-rumped parrots (Psephotus haematonotus) was investigated during part of the reproductive period including courtship and incubation. On 2 test days 14 pairs in either the courtship or the breeding state were confronted with three unknown objects in their familiar aviary for 6 h on each of 2 days. Test days were separated by a 2-day pause. Exploration by the males did not change from courtship to breeding, whereas in females latency to first contact increased, and duration of exploration and the number of objects touched decreased from courtship to breeding state. Considering the pair as a unit, the total duration of exploration was shorter in breeding pairs than in pairs during courtship. Changes in exploration from the first to the second day of object exposure occurred in both sexes. Males explored longer on the second day, females contacted the objects significantly later on the second day but showed no significant changes in duration of exploration. The changes in exploration might be due to changed cost/benefit considerations during courtship and breeding.

Journal Article↗

PubMed1998

Space exploration in neglect.

The present study investigated the gaze as well as the head and the eye-in-head movements of neglect patients while they were exploring their surroundings. A random configuration of letters was presented on the inner surface of a sphere that surrounded the subject, requiring free exploratory eye and head movements. The subjects were requested to search for a single (non-existent) target letter. The co-ordination of eye and head movements in patients with neglect resembled the pattern usually observed in healthy subjects orienting to eccentric visual targets. They performed hypometric head movements with additional shifts of eye-in-head position. Moreover, like healthy subjects, the patients with neglect explored space with gaze, with head and eye-in-head movements that were symmetrically distributed around preferred orientations in space. However, in contrast to controls, these centres of exploration were shifted towards the right. The average horizontal position of gaze and of head movements lay right of the body's mid-sagittal plane, the average eye-in-head position right of the head midline. The preferred orientations were located far away from the anatomical limits of horizontal gaze, head and eye-in-head movements. The decrease of exploration towards more eccentric locations left and right of these orientations thus could not be explained by anatomical restrictions. The results argue against a model of neglect that proposes a lateral gradient of attentional orienting towards the ipsilesional side. Exploring the surroundings, the patients did not orient gaze, the head or the eyes in the head towards the extreme ipsilesional side, nor even close to it. The results favour a deviation model suggesting a shift of the whole frame for exploratory behaviour towards the ipsilesional side. In addition to this shift, we found a second component of altered visual exploration in neglect. The patients' head and gaze movements exhibited a reduced variability around the deviated centre of exploration. The variability was not generally reduced but rather concerned specifically the horizontal dimension. The latter was found even when the area of exploration was paralleled between the groups, requiring the control subjects to search only in that part of the letter array that the neglect patients had explored spontaneously. Possible mechanisms, such as a disturbed ability to update the spatial representation of visual targets or an altered neural representation of space in the horizontal dimension, are discussed.

Aged↗

PubMed2002

Unilateral versus bilateral neck exploration for primary hyperparathyroidism: a prospective randomized controlled trial.

OBJECTIVE: To compare unilateral and bilateral neck exploration for primary hyperparathyroidism in a prospective randomized controlled trial. SUMMARY BACKGROUND DATA: Based on the assumption that unilateral neck exploration for a solitary parathyroid adenoma should reduce operating time and morbidity, a variety of minimally invasive procedures have challenged the idea that bilateral neck exploration is the gold standard for the surgical treatment of primary hyperparathyroidism. However, to date, no open prospective randomized trial has been published comparing unilateral and bilateral neck exploration. METHODS: Ninety-one patients with the preoperative diagnosis of primary hyperparathyroidism were randomized to unilateral or bilateral neck exploration. Preoperative scintigraphy and intraoperative parathyroid hormone measurement guided the unilateral exploration. Gross morphology and frozen section determined the extent of parathyroid tissue resection in the bilateral group. The primary end-point was the use of postoperative medication for hypocalcemic symptoms. RESULTS: Eighty-eight patients (97%) were cured. Histology and cure rate did not differ between the two groups. Patients in the bilateral group consumed more oral calcium, had lower serum calcium values on postoperative days 1 to 4, and had a higher incidence of early severe symptomatic hypocalcemia compared with patients in the unilateral group. In addition, for patients undergoing surgery for a solitary parathyroid adenoma, unilateral exploration was associated with a shorter operative time. The cost for the two procedures did not differ. CONCLUSIONS: Patients undergoing a unilateral procedure had a lower incidence of biochemical and severe symptomatic hypocalcemia in the early postoperative period compared with patients undergoing bilateral exploration. Unilateral neck exploration with intraoperative parathyroid hormone assessment is a valid surgical strategy in patients with primary hyperparathyroidism with distinct advantages, especially for patients with solitary parathyroid adenoma.

Adenoma↗

PubMed1995

Do caries explorers transmit infections with persons? An evaluation of second molar caries onsets.

UNLABELLED: Dental caries explorers may become contaminated during routine caries examinations with pathogenic organisms and thereby potentially transmit infections from one tooth to another within a patient. The purpose of this study was to test the hypothesis that the contamination status of explorers influenced the caries risk of second molars. Two explorer contamination statuses were defined: (1) contamination status 1--explorers which had probed a carious molar just prior to examining the second molar, and (2) contamination status 2--sterile explorers versus explorers which had probed several teeth. Caries examinations were performed by 4 dentists on a cohort of 4th grade students in Belize City. The examination dates and sample sizes (n) were: September-October 1989 (n = 1,277), January 1991 (n = 1,111), and January 1992 (n = 961), and January-February 1993 (n = 861). Within this cohort, there were 221 subjects who (1) had at least one pit and fissure carious onset on a caries-free second molar, (2) had no evidence of dental treatments, and (3) were examined by the same examiner during the entire study. After adjusting for confounding variables, the examination of a second molar with a dental caries explorer in either contamination status 1 or 2 had no substantial effect on the caries risk (rate ratio 0.95, 95% confidence interval: 0.77-1.18, and rate ratio 1.18, 95% confidence interval: 0.89-1.56, respectively). If a true rate ratio of 1.7 or greater was associated with the contamination status 1 and 2, these analyses had more than 99 and 80% probability of detecting it, respectively. CONCLUSIONS: Examining a sound second molar with a contaminated dental explorer either does not affect the caries risk, or results in such a small increase in caries risk that it can only be reliably identified in studies where the exposure of sound teeth to contaminated dental explorers is randomized.

Child↗

PubMed1990

100 consecutive common duct explorations without mortality.

It has been suggested that the incidence of morbidity and mortality after common duct exploration no longer justifies its use in patients with a gallbladder in situ. Therefore endoscopic sphincterotomy has been advocated for removal of common duct stones before cholecystectomy in selected patients. The purpose of this study was to determine our current rate of retained common duct stones and the morbidity and mortality rates associated with common duct exploration. Charts of 100 consecutive patients who underwent cholecystectomy and common duct exploration from January 1982 through December 1986 were reviewed. Indications for duct exploration included jaundice, dilated common bile duct, gallstone pancreatitis, multiple small stones, and abnormal intraoperative cholangiogram. Common duct exploration was done by manual technique or choledochoscopy, as determined by the surgeon's preference. Only two patients required duodenotomy for extraction of difficult stones. There were no deaths in this series of consecutive common duct exploration. The total morbidity rate was 15.7%, which included a 5.3% incidence of retained common duct stones. There was a 7.4% major complication rate, including deep vein thrombosis, bleeding gastric ulcer, and pneumonia. The remaining complications were minor and did not prolong hospitalization. There was one wound infection and no postoperative pancreatitis. None of the complications were directly attributable to choledochotomy or duct exploration. All retained common duct stones were removed by endoscopic retrograde cholangiopancreatography or by angiographic basket and did not require reoperation. It is concluded that operative common duct exploration not requiring duodenotomy is safe and does not appreciably increase the incidence of complications after cholecystectomy. Endoscopic sphincterotomy continues to be the preferable alternative to operative common duct exploration for patients with retained common duct stones.

Cholangiopancreatography, Endoscopic Retrograde↗

PubMed1997

Sestamibi scanning is inadequate for directing unilateral neck exploration for first-time parathyroidectomy.

OBJECTIVE: To determine whether technetium Tc 99m sestamibi scanning is accurate enough to allow surgeons to perform unilateral neck exploration for first-time parathyroidectomy in patients with primary hyperparathyroidism. DESIGN: Retrospective review. SETTING: University tertiary care center. PATIENTS: Forty patients with primary hyperparathyroidism who underwent sestamibi scanning before first-time parathyroidectomy, of whom 28 had single adenomas, 9 had multiple adenomas, and 3 had hyperplasia. INTERVENTIONS: All 40 patients underwent bilateral neck exploration with identification of 4 parathyroid glands. MAIN OUTCOME MEASURES: We compared the results of preoperative sestamibi scanning with operative and histologic findings. We then used these data to calculate the projected success rates of parathyroidectomy if unilateral neck explorations had been performed based on the results of sestamibi scanning, instead of bilateral explorations. RESULTS: Sestamibi scanning was correct in 20 (71%) of 28 patients with single adenomas, 4 (44%) of 9 patients with multiple adenomas, and 0 (0%) of 3 patients with hyperplasia. If unilateral neck explorations had been performed on the basis of localization by sestamibi scanning, parathyroidectomy would have failed in 4 (10%) of 40 patients. CONCLUSIONS: Sestamibi scanning, although helpful, is inadequate for directing unilateral neck exploration for first-time parathyroidectomy. Surgeons who perform unilateral neck exploration based on the results of sestamibi scanning will record a higher failure rate and incur higher costs than those who perform bilateral neck exploration for first-time parathyroidectomy.

Adolescent↗

PubMed1998

Parathyroidectomy via bilateral cervical exploration: a retrospective review of 866 cases.

INTRODUCTION: Parathyroidectomy via cervical exploration is an effective primary-modality treatment for hyperparathyroidism, with cure rates of greater than 95%. We retrospectively reviewed 866 consecutive parathyroidectomies performed by a single surgeon between 1960 and 1997. We attempted to describe the polymorphic variation in multiglandular disease, the anatomic locations of pathologic glands, and the operative strategy and techniques which we believed were important to minimizing morbidity and maximizing curative success. METHODS: The cases of 329 males and 537 females (age, 1-88 years) were reviewed. There were 766 operations performed: primary hyperparathyroidism (713), tertiary hyperparathyroidism (100), reoperations (53). The strategy for primary exploration includes a bilateral neck exploration, early recurrent laryngeal nerve skeletonization, and identification of at least four glands. RESULTS: Normocalcemia was achieved in 98.2% of cases after initial cervical exploration. Persistent hypercalcemia occurred in 7 patients (<1%). Nine patients (1%) suffered persistent postoperative hypocalcemia. Unilateral recurrent laryngeal nerve injury occurred in two patients (<1%). Other perioperative complications included: reoperation for hematoma, repaired carotid artery injury, unexplained dysphagia, pneumothorax, deep venous thrombosis, and aspiration pneumonia. There were two mortalities (<1%) attributable to severe, comorbid disease. Ectopic glands were found in 120 cases. The frequency of glands at these sites were as follows: mediastinal (4.9%), intrathymic (8.4%), intrathyroid (6.7%), and retroesophageal/retrotracheal (3.5%). Thyroid resections provided diagnosis of concomitant thyroid carcinoma in 8.0% of resected patients. The pathology of patients with primary hyperparathyroidism (PHPT) consisted of single adenomas (77.2%), hyperplasia (21.0%), normal glands (1%), double adenomas (<1%), and parathyroid carcinoma (<1%). The distribution of adenomas was as follows: left upper, 25.3%; left lower, 27.3%; right upper, 26.8%; right lower, 20.6%. Hyperplastic glands were found in ectopic positions as follows: intrathymic (7.5%), intrathyroid (11.3%), mediastinal (2.5%), and retroesophageal/retrotracheal (0%). The average volume difference between the largest and smallest hyperplastic gland of each case was 1.80 + 4.40 cm3. Reoperations were performed upon 53 referred patients and 7 patients after failed exploration. Normocalcemia was attained in 98.3% of cases. Glandular pathology was identified in the previous operative field in 52 patients (86.7%). Adenomas were identified in 56.0% (n = 23) and hyperplasia in 39.0% (n = 16). CONCLUSIONS: In our series, we were able to attain normocalcemia in 98.2% of cases after initial cervical exploration. We believe that identification of four glands, an exhaustive search of ectopic sites, bilateral exploration, and liberal use of biopsy and intraoperative frozen section were essential to curative success. The pathologist should identify parathyroid tissue in the specimen and differentiate the "abnormal" from "normal" gland. Morphologic criteria alone cannot be used because of polymorphic variation in hyperplasia in which pathologic glands may appear normal. Early identification of the recurrent laryngeal nerve allows for a safer neck exploration by alerting the surgeon to the location and course of the nerve. A bilateral approach does not contribute increased morbidity from recurrent laryngeal nerve injury.

Adolescent↗

PubMed2006

Randomized clinical trial comparing scan-directed unilateral versus bilateral cervical exploration for primary hyperparathyroidism due to solitary adenoma.

BACKGROUND: It was shown in a previous retrospective study that scan-directed unilateral cervical exploration for primary hyperparathyroidism (HPT) can be carried out without an increase in the incidence of persistent or recurrent hypercalcaemia. This randomized clinical trial was conducted to test the hypothesis that focused unilateral operation leaves the patient no more vulnerable to persistent HPT than standard bilateral neck exploration. METHODS: Patients with HPT routinely underwent preoperative dual-isotope subtraction scintigraphy in an attempt to localize the presumed solitary parathyroid adenoma. Individuals with a positive scan (one residual focus of activity following subtraction) were deemed suitable for focused unilateral cervical exploration. At operation, if a single tumour was identified at the site suggested by the scan, the patient was randomized to unilateral or bilateral neck exploration. RESULTS: Between April 1998 and December 2003, 190 patients underwent first-time cervical exploration for HPT. Of these, 100 qualified for randomization. Fifty-four patients were randomized to unilateral neck exploration and 46 to bilateral operation. All 100 patients were cured following operation, as assessed by return of the serum calcium level to normal. Two patients randomized to bilateral exploration were found to have an unsuspected additional enlarged parathyroid on the contralateral side. CONCLUSION: Scan-directed unilateral cervical exploration for HPT does not significantly increase the incidence of persistent hypercalcaemia compared with standard bilateral operation.

Adenoma↗

PubMed1977

Exploration and play with objects in domestic kittens.

The responses of 12 kittens to unfamiliar and familiar objects was tested. Four categories of behavior were measured: exploration, play-exploration, play, and non-manipulatory contact. The results indicated that exploration and play-exploration were used for longer durations with unfamiliar objects and play was used for longer durations with familiar objects. Rank-order correlations between the measures showed that objects explored were not correlated with objects played with or play-explored. Analyses of the rankings revealed that small size and mobility were important object properties of play. The results suggest that exploration involves learning about stimulus properties, play-exploration involves learning about perceptual-motor properties, and play involves learning to coordinate movements with those of moving objects.

Animals↗

PubMed1996

Ocular exploration of space as a function of neck proprioceptive and vestibular input--observations in normal subjects and patients with spatial neglect after parietal lesions.

We recently argued that the specific compensation of spatial neglect by manipulating neck proprioceptive and vestibular input is due to a central "correction" of the disturbed neural transformation process converting the afferent input coordinates from the peripheral sensory organs into a central representation of egocentric space. Both types of stimulation were proposed to induce a reorientation of the deviated or distorted egocentric spatial reference frame. The aim of the present study was to observe this process of reorientation under a condition in which no visual stimulus can attract the subject's attention and thus influence exploration behaviour from outside. We recorded eye movements of normal subjects and of three patients with spatial neglect after right parietal lesions while searching for a non-existent target in complete darkness. It was assumed that the area of the outer space that subjects spontaneously explore under this condition is a direct function of the subject's representation of egocentric space. Ocular space exploration was biased and confined almost entirely to the right side of the midsagittal plane in patients with neglect. This spatial distribution of exploratory eye movements changed remarkably with left-sided neck muscle vibration as well as with left-sided vestibular stimulation using ice water calorics. The spatial area of exploration was significantly enlarged to the contralesional side and the exploration maximum shifted in the same direction. Whereas with both types of stimulation space exploration of patients with neglect was similar to that of normal subjects when not being stimulated, neck proprioceptive and vestibular stimulation in normal subjects induced a quasi neglect-like exploration pattern, i.e. a bias to one side of the objective midsagittal plane. If ocular space exploration was, however, related to the subjectively perceived position of the midsagittal plane in space, eye movements were symmetrically distributed and carried out to both sides of subjective "straight ahead" in all experimental conditions, in normal subjects as well as in patients with neglect. The present results support the above hypothesis and indicate that neck proprioceptive as well as vestibular input directly contribute to the computation of the subject's central representation of egocentric space used for localizing body orientation and for guiding motor behaviour in space.

Adult↗

PubMed2006

Exploration for hemorrhage following laparoscopic renal surgery: intraoperative findings.

PURPOSE: Bleeding after surgery is a rare but potentially life threatening complication. We reviewed operative and postoperative clinical features in patients who required surgical exploration secondary to hemorrhage following laparoscopic renal procedures. MATERIALS AND METHODS: We retrospectively reviewed the records of patients undergoing laparoscopic renal surgery between January 1996 and September 2004. Nine of 1,123 patients (0.8%) underwent early exploration for bleeding within 5 days of surgery. RESULTS: Two groups were identified. Group 1 consisted of 4 patients who underwent early exploration at less than 10 hours after surgery and had arterial bleeding. Group 2 consisted of 5 patients who underwent exploration a mean 38 hours after surgery and in whom no bleeding source was identified. Group 1 patients had pronounced hypotension with systolic blood pressure 70 to 79 mmHg and hematocrit decreases (mean 10.5%) in a short time course before repeat exploration (mean 4.5 hours). Arterial bleeding was identified in the hilum and adrenal bed. Group 2 patients demonstrated a decrease in hematocrit from an initial mean of 28.3% to 22.5% with tachycardia and mild hypotension (systolic blood pressure 90 to 99 mmHg). On exploration group 2 patients had diffuse oozing. Mean hospital stay in group 1 was 8 days (range 4 to 9) vs 12 (range 6 to 24) in group 2. CONCLUSIONS: Early hemodynamic instability after laparoscopic renal surgery is likely to indicate a discrete arterial bleeding source from the hilum or adrenal bed, requiring surgical control. In patients who underwent exploration after a delayed bleeding presentation no discrete source was found intraoperatively. Therefore, it is unclear whether these patients benefited from surgical exploration.

Adult↗

PubMed2001

Active, passive and snapshot exploration in a virtual environment: influence on scene memory, reorientation and path memory.

We investigated the importance of active, passive and snapshot exploration on spatial memory in a virtual city. The exploration consisted in traveling along a series of streets. 'Active exploration' was performed by giving directions to the subject who controlled his displacement with a joystick. During 'passive' exploration, the travel was imposed by the computer. Finally, during 'snapshot exploration', simple views of the scene were presented sequentially every 4 m. Travel velocity was the same in all cases. The three visual exploration modes were compared with three spatial memory measures: (1) scene recognition, (2) at the end of the path, reorientation toward the departure point and (3) drawings of the path shape. Scene recognition and estimation of the direction of the starting point of the path were not affected by the mode of exploration. In contrast, reproduction of the shape of the path was affected: the errors of reproduction were greater for the snapshot exploration than for the other two conditions; there was no difference between the other two conditions. These results suggest that (1) 2D image features from a visual scene are memorized. Moreover, (2) pointing towards the origin of the path relies on motion duration integration or a frame of reference integrated during displacement. Finally, (3) drawing the path shape involves a deliberate reconstruction process.

Adult↗

PubMed2003

Unilateral exploration for primary hyperparathyroidism.

OBJECTIVE: To examine the efficacy of using pre-operative imaging studies (Sesta-MIBI scan and ultrasonography) to localize the pathology and allow for unilateral neck exploration to assess its safety. DESIGN: Descriptive analytical study. PLACE AND DURATION OF STUDY: Department of Surgery/ENT, Pakistan Institute of Medical Sciences (PIMS), Islamabad. SUBJECTS AND METHODS: Twenty-three patients were reviewed, who underwent operation for primary hyperparathyroidism (PHPT) in our institution between 1995 and 2002. A total of 49 enlarged parathyroid glands were removed. Patients were divided into two groups. In group-A (in which only unilateral exploration was done) there were 21 patients (42 glands). In group-B, bilateral exploration was done, which included 2 patients and 7 glands. Sesta-MIBI scan and ultrasonography were done in all cases. Results were analyzed statistically with appropriate tests of significance. RESULTS: Sesta-MIBI scan showed an accuracy of 91% (20 adenomas) whereas ultrasound was positive in 18 patients (78%). One case of adenoma and 2 cases of hyperplasia were not detected by pre-operative imaging. Unilateral exploration of neck was successful in 19 cases of adenoma. The parameters used for successful exploration were corrected serum calcium and parathyroid hormone levels. Ultrasound was positive in 18 patients (78%). There was a significant difference in surgical time between the unilateral and bilateral neck explorations (45 minutes). Unilateral neck exploration for hyperparathyroidism has been successful in curing hypocalcaemia 22/23(95%). CONCLUSION: At least two pre-operative localization tests, a Sesta-MIBI scan and ultrasonography, should be done for accurate localization of an abnormal parathyroid gland especially adenoma. Selective unilateral exploration is safe and reliable if the second ipsilateral gland is normal macroscopically or microscopically.

Adenoma↗

PubMed2000

Initial neck exploration for untreated hyperparathyroidism.

This study represents the experience of the Department of Surgery at the University of Louisville over a 21-year interval. Many aspects of surgical management of hyperparathyroidism have changed over the last 2 decades; controversies regarding the extent of exploration and the value of preoperative localization studies remain unresolved. One hundred ninety-three patients underwent neck exploration for hyperparathyroidism from 1976 to 1997. Data were collected from four University of Louisville-affiliated hospitals by independent evaluators. One hundred sixty patients with untreated hyperparathyroidism underwent neck exploration. Preoperative localization was carried out in 52 per cent (83 of 160). The exact location of the abnormal gland was indicated in 55 per cent (46 of 83), and the correct side of the neck was identified in 74 per cent (61 of 83). Technetium sestamibi scan was most reliable and identified the abnormality in 83 per cent (24 of 29). The average operative time with preoperative localization was 118 minutes compared with 137 minutes without preoperative localization. Intraoperative methylene blue was used in 42 of 160 neck explorations. Average operative time with methylene blue was 102 minutes compared with 124 minutes without methylene blue. Thirty-seven per cent (59 of 160) of patients underwent unilateral neck exploration. Sixty-three per cent (101 of 160) underwent bilateral exploration. Successful exploration was conducted in 98 per cent of the unilateral group and 91 per cent of the bilateral group. Postoperative local complications were essentially the same in both groups (3%), whereas temporary hypocalcemia occurred in 24 per cent (24 of 101) of the bilateral group compared with 3 per cent (2 of 59) of the unilateral group. We conclude that neck exploration for hyperparathyroidism is a highly successful, safe treatment with no mortality and minimal morbidity. Preoperative localization studies modestly reduced the duration of surgery without improving outcome.

Adolescent↗

PubMed1990

Choledochoscopy and common bile duct exploration.

Common bile duct (CBD) exploration is often indicated when cholecystectomy is performed for gallstone disease. Choledochoscopy may help to decrease the incidence of retained common duct stones. The present study reviews 97 consecutive CBD exploration cases performed between 1980 and 1988, in order to evaluate the authors' experience with flexible choledochoscopy and CBD exploration. Fifty-nine patients had CBD exploration plus flexible choledochoscopy and 38 underwent CBD exploration alone. Retained stones were found postoperatively in ten per cent of the patients who had only CBD exploration versus four per cent in the choledochoscopy group. The retained stones in five patients were later removed by percutaneous basket retrieval (3), flush irrigation (1), and choledochoscopy (1). Flexible choledochoscopy detected additional stones after routine CBD exploration in 12 patients, clarified T-tube cholangiograms in four patients, and aided stone extraction in two patients. For these reasons, and because choledochoscopy was associated with a lower incidence of retained stones, the authors believe this procedure is a worthwhile addition in most cases of CBD exploration.

Cholecystectomy↗

PubMed1986

Abdominal exploration for suspected recurrent carcinoma of the colon and rectum based upon elevated carcinoembryonic antigen alone or in combination with other diagnostic methods.

Thirty-six patients underwent abdominal exploration due to elevated carcinoembryonic antigen (CEA) levels after a curative resection for carcinoma of the colon and rectum. Three groups were evaluated. In group 1, CEA elevation alone was the indication for the exploration in 13 asymptomatic patients. In group 2, 13 other asymptomatic patients underwent exploration because of elevated CEA levels in combination with other findings. In group 3, ten patients were symptomatic with an elevated CEA level at the time of exploration. Five patients from groups 1 and 2 underwent a curative resection for recurrent tumor (14 per cent). Three of these patients are still alive more than five years after exploration. Nine patients had negative findings at exploration for tumor recurrence (25 per cent false-positive results). Six of these patients are alive while three have died of metastatic disease. Twenty-two of the 36 patients (61 per cent) had unresectable disease at the time of exploration. Four of these patients underwent some form of surgical palliative procedure. Considering the five patients who underwent a curative resection with the latter four patients, this results in 25 per cent of the patients benefitting from surgical exploration.

Adult↗

PubMed1993

Success of unilateral neck exploration for sporadic primary hyperparathyroidism.

BACKGROUND: Unilateral neck exploration for primary hyperparathyroidism (PHPTH) is controversial because of concern about missed multiglandular disease. METHODS: In patients with sporadic PHPTH our approach has been arbitrarily to surgically explore the right neck first unless preoperative or intraoperative evidence suggests left-sided parathyroid pathologic condition. When an adenoma is identified and a normal ipsilateral gland is confirmed on histologic examination, the contralateral side is not explored. A 15-year series of 371 patients with sporadic PHPTH was reviewed retrospectively to determine the efficacy of this strategy. RESULTS: At operation unilateral exploration was possible in 125 patients (34%). Of these 122 had a single adenoma and two patients had parathyroid carcinoma. One patient with unrecognized hyperplasia required subsequent subtotal parathyroidectomy. There were no major complications. Bilateral surgical exploration was required in 246 patients including 18 with hyperplasia, 4 with double adenomas, and 4 with parathyroid cancer. Bilateral surgical exploration failed in 18 patients (14 persistent and 4 recurrent PHPTH) and was complicated by one recurrent nerve palsy and two cases of permanent hypocalcemia. Operative time was significantly shorter in the unilaterally explored group. CONCLUSIONS: When possible, unilateral exploration for PHPTH is safe and effective, avoids obliterative scarring of the contralateral neck, and may reduce morbidity and operative time.

Adenoma↗

PubMedDate not supplied

Verification and maintenance of dental explorer sharpness.

An ongoing study of the relationship between different chewing gums, remineralization, and caries rates was started in 1989 in Belize, Central America. Initially 1277 children, age 10 years, were assigned in equal randomized groups to four dentists who had been trained to identify a standard of caries diagnosis. The same children were examined according to a modified WHO caries code by the same dentist in each of the three subsequent years. To eliminate one possible variable, all 200 dental explorers used were examined under a X20 binocular Bausch and Lomb dissecting microscope initially and at each exam period. Any explorer not comparable to an explorer that was originally marked and kept unused as a standard was sharpened by hand on an Arkansas oilstone wetted with engine oil for lubrication. Explorers that could not be restored to a condition comparable at X20 to the standard were discarded. Approximately 10% of the explorers needed correction at each exam period and about 1% were discarded. In any study related to dental caries evaluation with dental explorers or comparison of explorer use versus nonuse, verification and maintenance of sharpness of used and even new dental explorers should be addressed to remove that factor as a possible variable.

Child↗