Biomedical subjects

J Wong

Publications and source records attributed to J Wong.

At least 379 records · Page 21Linked to original sources

PubMed1996

Prospective clinical evaluation of an electronic portal imaging device.

PURPOSE: To determine whether the clinical implementation of an electronic portal imaging device can improve the precision of daily external beam radiotherapy. METHODS AND MATERIALS: In 1991, an electronic portal imaging device was installed on a dual energy linear accelerator in our clinic. After training the radiotherapy technologists in the acquisition and evaluation of portal images, we performed a randomized study to determine whether online observation, interruption, and intervention would result in more precise daily setup. The patients were randomized to one of two groups: those whose treatments were actively monitored by the radiotherapy technologists and those that were imaged but not monitored. The treating technologists were instructed to correct the following treatment errors: (a) field placement error (FPE) > 1 cm; (b) incorrect block; (c) incorrect collimator setting; (d) absent customized block. Time of treatment delivery was recorded by our patient tracking and billing computers and compared to a matched set of patients not participating in the study. After the patients radiation therapy course was completed, an offline analysis of the patient setup error was planned. RESULTS: Thirty-two patients were treated to 34 anatomical sites in this study. In 893 treatment sessions, 1,873 fields were treated (1,089 fields monitored and 794 fields unmonitored). Ninety percent of the treated fields had at least one image stored for offline analysis. Eighty-seven percent of these images were analyzed offline. Of the 1,011 fields imaged in the monitored arm, only 14 (1.4%) had an intervention recorded by the technologist. Despite infrequent online intervention, offline analysis demonstrated that the incidence of FPE > 10 mm in the monitored and unmonitored groups was 56 out of 881 (6.1%) and 95 out of 595 (11.2%), respectively; p < 0.01. A significant reduction in the incidence of FPE > 10 mm was confined to the pelvic fields. The time to treat patients in this study was 10.78 min (monitored) and 10.10 min (unmonitored). Features that were identified that prevented the technologists from recognizing more errors online include poor image quality inherent to the portal imaging device used in this study, artifacts on the portal images related to table supports, and small field size lacking sufficient anatomical detail to detect FPEs. Furthermore, tools to objectively evaluate a portal image for the presence of field placement error were lacking. These include magnification factor corrections between the simulation of portal image, online measurement tools, image enhancement tools, and image registration algorithms. CONCLUSION: The use of an electronic portal imaging device in our clinic has been implemented without a significant increase in patient treatment time. Online intervention and correction of patient positioning occurred rarely, despite FPEs of > 10 mm being present in more than 10% of the treated fields. A significant reduction in FPEs exceeding 10 mm was made in the group of patients receiving pelvic radiotherapy. It is likely that this improvement was made secondarily to a decrease in systematic error and not because of online interventions. More significant improvements in portal image quality and the availability of online image registration tools are required before substantial improvements can be made in patient positioning with online portal imaging.

Brain Neoplasms↗

PubMed1996

Prognostic implication of proliferative markers MIB-1 and PC10 in esophageal squamous cell carcinoma.

BACKGROUND: Proliferative markers are related to tumor behavior. The commonly used markers are proliferating cell nuclear antigen (PCNA) and Ki-67. The aim of this study is to evaluate the usefulness of MIB-1 (for Ki-67) and PC10 (for PCNA) in the assessment of the clinicopathologic features and prognosis in patients with esophageal squamous cell carcinoma. METHODS: One hundred patients (88 males, 12 females; mean age, 63 years [range, 39 to 83 years]) with surgically resected esophageal squamous cell carcinoma (32 well differentiated, 51 moderately differentiated, and 17 poorly differentiated) were studied. The clinicopathologic features and survival data of these patients were noted. Representative tissue was collected from each tumor and immunohistochemical preparations for MIB-1 and PC10 were made. RESULTS: The percentages of cells that tested positive for PC10 and MIB-1 were much higher in tumor cells than in nonneoplastic cells. The pattern of expression of both markers varied with the differentiation of the tumor. The results observed with MIB-1 staining were better than those with PC10; because MIB-1 had less background staining, as well as stronger and more uniform positive signals compared with PC10. Thus, further investigation was performed on MIB-1-stained sections. The tumor cell MIB-1 scores ranged from 169 to 964 positive cells per 1000 cells (mean 598 +/- 211; median, 636). Although it was significantly associated with the differentiation of the tumor (P = 0.0001), the score had no significant relationship to the tumor size, location, or stage, or to the patients' age and sex. The prognosis depended on the size and stage of the lesion. In Stage III lesions (n = 83), patients with MIB-1 scores below 300 had longer actual survival rates than those with a score of 300 or above. However, the survival rates of patients in the latter group were better if the greatest dimension of the tumor diameter was 7.5 cm or less. CONCLUSIONS: Proliferative activity in esophageal squamous cell carcinoma, as defined by the MIB-1 immunohistochemical method, is significantly related to tumor differentiation. It is also potentially valuable as a prognostic marker in addition to its use in tumor staging and size.

Adult↗

PubMed1996

Pyogenic liver abscess. An audit of experience over the past decade.

OBJECTIVES: To audit our experience in managing patients with pyogenic liver abscesses since 1984 and to identify any risk factor associated with hospital mortality. DESIGN: Retrospective review. SETTING: A tertiary referral center. PATIENTS: Eighty-three patients with pyogenic liver abscesses were studied to determine demographic characteristics; clinical features, laboratory, imaging, and microbiologic findings; methods of treatment; and final outcome. The median follow-up period was 9.8 months. INTERVENTION: All patients were treated with intravenous antibiotic drugs. Fifty-three patients were to image-guided percutaneous aspiration of the abscess. A percutaneous drainage catheter was inserted after aspiration in 27 patients. Laparotomy was performed in 27 patients; seven of them underwent an elective operation. MAIN OUTCOME MEASURE: Hospital mortality, defined as death within the same hospital admission for management of liver abscess. RESULTS: Biliary tract disease was the most frequently identifiable cause. The right lobe abscess was more frequently cryptogenic, while the left lobe abscess was more frequently related to intrahepatic stones (P < .001). The overall hospital mortality rate was 18% (15/83). On univariate analysis, female gender, rupture on presentation, emergency laparotomy, management without aspiration or catheter drainage, presence of malignancy, hyperglycemia, hyperbilirubinemia, elevated prothrombin time, and elevated activated partial thromboplastin time were significantly associated with hospital mortality. On multivariate logistic regression analysis, presence of malignancy, hyperbilirubinemia, and elevated activated partial thromboplastin time were found to be independent risk factors. CONCLUSIONS: Pyogenic liver abscess is still a disease with significant mortality. Early diagnosis and prompt treatment are necessary to further improve our results of management.

Adult↗

PubMed1996

Tadpole competence and tissue-specific temporal regulation of amphibian metamorphosis: roles of thyroid hormone and its receptors.

Amphibian metamorphosis is a post-embryonic process that systematically transforms different tissues in a tadpole. Thyroid hormone plays a causative role in this complex process by inducing a cascade of gene regulation. While natural metamorphosis does not occur until endogenous thyroid hormone has been synthesized, tadpoles are competent to respond to exogenous thyroid hormone shortly after hatching. In addition, even though the metamorphic transitions of individual organs are all controlled by thyroid hormone, each occurs at distinct developmental stages. Recent molecular studies suggest that this competence of premetamorphic tadpoles to respond to the hormone and the developmental stage-dependent regulation of tissue-specific transformations are determined in part by the levels of thyroid hormone receptors and the concentrations of cellular free thyroid hormone. In addition, at least two genes, encoding a cytosolic thyroid hormone binding protein and a 5-deiodinase, respectively, are likely to be critical players in regulating cellular free thyroid hormone concentrations. This review discusses how all of these molecular components coordinate to induce amphibian metamorphosis in a correct spatial and temporal manner. These studies provide us with general clues as to how and why tissues become competent to respond to hormonal signals.

Amphibians↗

PubMed1996

Pattern of recurrence after oesophageal resection for cancer: clinical implications.

Patterns of disease recurrence were reviewed in 108 patients who had curative resection for squamous cell cancer of the thoracic oesophagus. At a median follow-up of 20 months, 56 patients (52 per cent) had recurrence. Most presented within 2 years. Extrathoracic recurrence was found in 41 per cent of patients and intrathoracic recurrence in 25 per cent. Systemic organ metastases (26 per cent) were as frequent as intrathoracic recurrences. Twelve patients (11 per cent) developed cervical lymph node (CLN) recurrence; their mean time to recurrence was 12.6 months, compared with 13.1 months for recurrence at locations other than the neck (P = 0.8). Median survival was 23 and 13 months respectively (P = 0.27). Preoperative chemotherapy lowered the recurrence rate from 60 per cent to 30 per cent, (P = 0.01) but did not affect survival. The addition of cervical lymphadenectomy would benefit few patients and must be counterbalanced with increased morbidity and cost. The frequency of systemic organ metastases calls for further investigation of the possible benefits of chemotherapy.

Adenocarcinoma↗

PubMed1996

Hepatectomy with an ultrasonic dissector for hepatocellular carcinoma.

This study compared the results of hepatectomy for hepatocellular carcinoma (HCC) using an ultrasonic dissector with those of a combination of the crushing clamp and finger fracture techniques. The crushing clamp and finger fracture method was used from 1989 to 1992 in 96 patients (group 1) and the ultrasonic dissector from 1993 to 1994 in 69 patients (group 2). Data from these two sets of patients were collected prospectively. The groups were comparable in terms of preoperative liver function, tumour size and stage, and the incidence of cirrhosis. Major hepatectomy was performed in 69 patients (72 per cent) of group 1 and in 52 (75 per cent) of those in group 2. Use of the ultrasonic dissector resulted in lower mean (s.e.m.) blood loss (group 1 3.4(0.4) litres versus group 2 2.4(0.2) litres, P = 0.02), lower mean (s.e.m.) blood transfusion requirement (2.2(0.2) versus 1.2(0.2) litres, P = 0.001) and more patients not requiring blood transfusion (8 per cent of group 1 versus 32 per cent of group 2, P = 0.0001). Postoperative complications occurred in 45 patients (47 per cent) of group 1 and 19 (28 per cent) of those in group 2 (P = 0.012). There were no deaths in group 2 whereas the hospital mortality rate in group 1 was 16 of 96 (17 per cent) (P = 0.0004). A wider tumour-free resection margin (mean(s.e.m.) 1.2(0.1) versus 0.9(0.1) cm, P < 0.05) and lower serum bilirubin level throughout the postoperative period were also observed in group 2 patients. The ultrasonic dissector is better than the crushing clamp and finger fracture technique in hepatectomy for HCC.

Blood Loss, Surgical↗

PubMed1996

The effect of novobiocin on solvent production by Clostridium acetobutylicum.

Cells of Clostridium acetobutylicum treated with novoblocin, a DNA gyrase inhibitor, produced higher butyrate levels and lower solvent levels with acetone being the most affected. Seven enzyme activities involved in acid and solvent production were analyzed. Among them, only CoA transferase, required for acetone formation and acid uptake, experienced a significant decrease in activity. As in Escherichia coli and Bacillus subtilis, DNA from C. acetobutylicum became less negatively supercoiled in the early stationary phase (solventogenic stage), as shown by analysis of linking number of a reporter plasmid by agarose gel electrophoresis in the presence of chloroquine.

Acetates↗

PubMed1996

The gag coding region of the Drosophila telomeric retrotransposon, HeT-A, has an internal frame shift and a length polymorphic region.

A major component of Drosophila telomeres is the retrotransposon HeT-A, which is clearly related to other retrotransposons and retroviruses. This retrotransposon is distinguished by its exclusively telomeric location, and by the fact that, unlike other retrotransposons, it does not encode its own reverse transcriptase. HeT-A coding sequences diverge significantly, even between elements within the same genome. Such rapid divergence has been noted previously in studies of gag genes from other retroelements. Sequence comparisons indicate that the entire HeT-A coding region codes for gag protein, with regions of similarity to other insect retrotransposon gag proteins found throughout the open reading frame (ORF). Similarity is most striking in the zinc knuckle region, a region characteristic of gag genes of most replication-competent retroelements. We identify a subgroup of insect non-LTR retrotransposons with three zinc knuckles of the form: (1) CX2CX4HX4C, (2) CX2CX3HX4C, (3) CX2CX3HX6C. The first and third knuckles are invariant, but the second shows some differences between members of this subgroup. This subgroup includes HeT-A and a second Drosophila telomeric retrotransposon, TART. Unlike other gag regions, HeT-A requires a -1 frameshift for complete translation. Such frameshifts are common between the gag and pol sequences of retroviruses but have not before been seen within a gag sequence. The frameshift allows HeT-A to encode two polypeptides; this mechanism may substitute for the post-translational cleavage that creates multiple gag polypeptides in retroviruses. D. melanogaster HeT-A coding sequences have a polymorphic region with insertions/deletions of 1-31 codons and many nucleotide changes. None of these changes interrupt the open reading frame, arguing that only elements with translatable ORFs can be incorporated into the chromosomes. Perhaps HeT-A translation products act in cis to target the RNA to chromosome ends.

Amino Acid Sequence↗

PubMed1996

Laparoscopic cholecystectomy for acute cholecystitis in the elderly.

This study reviewed the results of laparoscopic cholecystectomy for acute cholecystitis in the elderly. Among 557 patients who underwent laparoscopic cholecystectomy, 70 (12.6%) had a clinical diagnosis of acute cholecystitis confirmed by ultrasonography. There were 28 men and 42 women with a mean age of 59.9 years (range 20-87 years). Thirty patients >/= 65 years of age were compared to 40 patients < 65 years old. Elderly patients had a higher female predominance (p < 0.05), a higher incidence of intercurrent diseases (p < 0.05), and a higher serum urea level (p < 0.001). The proportions of patients who underwent early or delayed surgery were comparable. There was no difference in operation time, postoperative analgesic requirements, or complications. Elderly patients, however, had a significantly higher conversion rate (23.3% versus 2.5%;p < 0.05). Even after successful laparoscopic cholecystectomy, there was a longer delay before ambulation (p < 0.05) and resumption of normal diet (p = 0. 08) with resulting prolonged postoperative (p = 0.08) and total hospital stay (p < 0.05). Laparoscopic cholecystectomy is a safe, effective treatment for acute cholecystitis in the elderly. When compared to younger patients, elderly patients are at greater risk for conversion, delayed recovery, and prolonged hospital stay.

Acute Disease↗

PubMed1996

Recombination-induced variants of Clostridium acetobutylicum ATCC 824 with increased solvent production.

Three sporulation-specific genes (orfA, sigE, sigG) from clostridium acetobutylicum ATCC 824 are arranged in a cluster, encoding the putative sigma E-processing enzyme, sigma E, and sigma sigma G respectively. When they were transformed into Clostridium acetobutylicum while on a plasmid functional in this organism, transformants did not survive. Three kinds of recombinations were then attempted with nonreplicative plasmids: duplication of orfA and sigE, replacement of all of the three genes, and inactivation of orfA. While the wild-type strain ceased to grow and produce solvents in batch cultures after approximately 24 h, mutant strains were isolated that showed sustained growth for a much longer time and produced a threefold increase in acetone and butanol in test tube cultures. In addition, one of the derived strains showed a significantly higher growth rate. Features of the restriction maps of the recombinants did not correlate with expected maps, indicating possible complications occurring during the recombination events.

Clostridium↗

PubMed1996

Dietary supplementation with L-arginine fails to restore endothelial function in forearm resistance arteries of patients with severe heart failure.

OBJECTIVES: We sought to examine the efficacy of dietary supplementation of L-arginine on endothelium-dependent vasodilation in patients with congestive heart failure. BACKGROUND: Endothelial dysfunction, as evidenced by a diminished response to such vasodilators as acetylcholine, is well defined in patients with heart failure. These responses are improved by intraarterial infusion with L-arginine. Because L-arginine is a semi-essential amino acid, we investigated the effects of dietary L-arginine on endothelium-dependent vasodilation in these patients. METHODS: Twenty patients with heart failure (New York Heart Association functional class III/IV, mean [+/- SE] age 51.3 +/- 1.7 years) and seven healthy control subjects (mean age 52.6 +/- 3.3 years) were studied. All patients continued taking their usual treatment. Responses to acetylcholine and sodium nitroprusside were determined using forearm plethysmography. Patients with heart failure received either L-arginine (20 g/day every day for 28 days) or placebo (vehicle syrup in equal amounts) in a double-blind protocol. The calculated power of the study was between 62% and 80% to detect a 30% to 40% change in area under the dose-response (forearm vascular resistance) curve. RESULTS: Responses to acetylcholine, but not to sodium nitroprusside, were significantly attenuated in patients with heart failure compared with control subjects (mean area under curve [AUC], control subjects vs. patients with heart failure: 1,125.4 +/- 164.5 vs. 617.3 +/- 116.6 U, p < 0.05, by Student t test). A significant increase in urea and aspartate transaminase levels in patients receiving active L-arginine treatment was observed. Responses to acetylcholine (AUC; before vs. after L-arginine: 641.5 +/- 126.7 vs. 695.9 +/- 151.9 U) and sodium nitroprusside were not affected by either L-arginine or placebo. CONCLUSIONS: Endothelial dysfunction was apparent in patients with heart failure despite rigorous vasoactive treatment. Oral administration with L-arginine was ineffective in influencing endothelial function in these patients.

Adult↗

PubMed1996

Oxygen consumption in the heart, hepatomesenteric bed, and brain in young and elderly human subjects, and accompanying sympathetic nervous activity.

Although the reduction in whole-body energy expenditure with aging has been well documented, there is little information about the changes that individual organs undergo. We therefore measured oxygen consumption in the heart, hepatomesenteric bed, and brain in elderly subjects and young controls, using central venous catheter techniques and the application of Fick's principle. We also measured whole-body, cardiac, and hepatomesenteric sympathetic nervous activity using isotope dilution methodology. Cardiac, hepatomesenteric, and cerebral oxygen consumption was similar in both groups. Whole-body and hepatomesenteric sympathetic nervous activity was also similar in the study groups, whereas cardiac norepinephrine (NE) spillover was significantly higher in the elderly. In contrast to the young, cardiac sympathetic nervous activity as assessed from NE spillover was not related to either cardiac oxygen consumption or cardiac work in the elderly. The data suggest that although oxygen consumption in the heart, hepatomesenteric bed, and brain are not different between young and elderly individuals, the relationship between sympathetic nervous activity and oxygen consumption in individual organs may alter with aging.

Adult↗

PubMed1996

Combined laparoscopic and endoscopic approach in patients with cholelithiasis and choledocholithiasis.

BACKGROUND: The Optimal management of common bile duct stones in patients undergoing laparoscopic cholecystectomy remains controversial. METHODS: A prospective study was conducted in 145 of the 481 patients who had a preoperative endoscopic retrograde cholangiogram before their laparoscopic cholecystectomy. RESULTS: Endoscopic retrograde cholangiogram was successful in 138 patients (95%), and common duct calculi were found in 72 (50%) of them. Endoscopic sphincterotomy with ductal clearance was achieved in 62 of 67 patients during a mean of 1.4 sessions (range, 1 to 5). Five (3.4%) patients had complications after endoscopic intervention, all of which resolved uneventfully . Fourteen patients underwent laparoscopic common duct exploration, five had failed endoscopic extraction, five had their common duct stones left intentionally for laparoscopic intervention, and, in addition, four of the seven patients who had a failed endoscopic retrograde cholangiogram had stones identified by intraoperative cholangiogram. Ten of these 14 patients underwent a successful laparoscopic common duct exploration. Laparoscopic cholecystectomy was successfully completed in 134 of the 145 patients, and none had major intraoperative or postoperative complications. The mean postoperative stay was 2.7 days for those patients who underwent a successful laparoscopic procedure. The overall mean number of admissions for completing the treatment was 2.3. CONCLUSIONS: Combined laparoscopic and endoscopic approach is a viable option for patients with gallstones and choledocholithiasis.

Adult↗

PubMed1996

Outcome studies for burn patients in Hong Kong: patients' satisfaction.

With the recent advances in burns treatment, many more survive the burn to experience pain, scarring, physical deformity, loss of function and psychological trauma. Pressure therapy prescribed by occupational therapists for more than 20 years in Hong Kong has proved its effectiveness in treating the visible scars. However, the inconvenience and impaired appearance that is brought about by these garments during the long phase of therapy bears some weight in worsening patients' social acceptance and happiness in life, also their families especially in children. The objects of the studies were to measure the subjective rating of the effectiveness of pressure therapy through patients' satisfaction towards treatment effectiveness and its effect on daily life. Seventy cases with burn injuries over 1 year previously were selected randomly among the centres for the survey. The scale used was ordinal from 1 to 6. Eleven items concerning treatment effectiveness, life at home, work and leisure aspects were questioned. Results were analysed into two streams-satisfaction towards pressure therapy and change of life satisfaction pre- and post-injury. Non-parametric tests were used for data analysis. Through the Wilcoxon Sign Rank Test and Cluster analysis, major determinants were identified. These factors also showed significant correlation with this demographic data. The conclusions helped to evaluate and improve the existing service in both the garment properties and our scope of therapy for these patients, especially in work rehabilitation and finally (sexual) counselling which should be addressed by a team with interdepartmental support.

Activities of Daily Living↗

PubMed1996

An initial appraisal of the clinical significance of Roseomonas species associated with human infections.

We reviewed laboratory, clinical, and epidemiologic data on 35 patients from whom organisms belonging to the genus Roseomonas, a pink-pigmented gram-negative coccobacillus, were isolated over a 22-year period (1972-1994). Roseomonas strains were most commonly isolated from middle-aged women with one of several underlying conditions, including cancer and diabetes. Roseomonas was most commonly isolated from the blood, in association with clinical signs of sepsis. Approximately 60% of all isolates were judged to be of possible clinical significance, either as primary or secondary pathogens; 75% of all strains were recovered in pure culture. Roseomonas gilardii was the most frequently isolated species and was significantly associated with septicemia and underlying immunocompromised conditions; the species of 29% of all Roseomonas isolates could not be unequivocally identified with presently available differential tests. Genomospecies 5, currently an unnamed taxon within the genus Roseomonas, was primarily recovered as a commensal from young adults attending a sexually transmitted diseases clinic. The findings suggest that although this genus appears to have an overall low pathogenic potential for humans, Roseomonas species-in particular, R. gilardii-may be significant pathogens in persons with underlying medical complications.

Adolescent↗

PubMed1996

Early versus delayed laparoscopic cholecystectomy for treatment of acute cholecystitis.

OBJECTIVE: The current study compared the results of early versus delayed laparoscopic cholecystectomy for treatment of acute cholecystitis. SUMMARY BACKGROUND DATA: Although recent reports have suggested the use of laparoscopic cholecystectomy for acute cholecystitis, the complication and conversion rates remain high. No data are available on whether initial medical treatment can improve the results. METHOD: Among 497 patients who underwent laparoscopic cholecystectomy, 52 (10.5%) had a clinical diagnosis of acute cholecystitis confirmed by ultrasonography. Twenty-seven of these patients had early surgery, that is, within 120 hours of admission, and 25 had interval cholecystectomy after initial medical treatment. RESULTS: The early group required modifications in operative technique more frequently (p < 0.001). The conversion rate (7.4%) and minor complication rate (22%) were comparable. Successful early laparoscopic cholecystectomy required a longer operative time (137.2 minutes vs. 98.0 minutes; p < 0.05) and postoperative hospital stay (4.6 days vs. 2.5 days; p < 0.005) but reduced the total hospital stay (6.4 days vs. 12.4 days; p < 0.001). CONCLUSIONS: Early laparoscopic cholecystectomy for the treatment of acute cholecystitis has no adverse effect on complication and conversion rates. Although it is technically demanding and time consuming, this procedure provides the economic advantage of a markedly reduced total hospital stay.

Acute Disease↗

PubMed1996

Primary aldosteronism. Results of surgical treatment.

SUMMARY BACKGROUND DATA: Management of primary hyperaldosteronism has undergone dramatic changes in the past 40 years. This retrospective study was carried out to review our recent surgical experience and to identify potential factors associated with postoperative persistent hypertension. METHODS: Forty-six patients who had adrenal surgery for primary hyperaldosteronism from 1983 to 1994 were included in the study. RESULTS: Periodic paralysis occurred in 12 (26%) patients. Hypertension and hypokalemia (mean serum potassium, 2.2 + 0.5 [+ standard deviation (SD) mmol/L) were present in all patients. Postural study was diagnostic in 85% (23 of 27). Computed tomography scan correctly localized the tumor in all except 1 patient, and venous sampling was performed in 11 patients. There was no operative mortality, and complications developed in six patients (13%), including one patient requiring re-exploration for hemostasis. All patients had a histologically documented adenoma. During a mean follow-up of 51 months, 34 (77%) of the 44 patients required no further antihypertensive treatment. Two patients were lost to follow-up. Age, response to spironolactone treatment, and blood pressure on discharge were risk factors identified for persistent hypertension. CONCLUSION: Primary hyperaldosteronism due to aldosterone-producing adenoma can be diagnosed and localized expeditiously, whereas surgical treatment can be performed safely. Hypokalemia may be cured by surgical treatment, although persistent hypertension, usually of a mild degree, still occurs in selected patients.

Adrenalectomy↗

PubMed1996

Accuracy and precision of in vitro volumetric measurements by three-dimensional sonography.

RATIONALE AND OBJECTIVES: A radiologist often wishes to measure organ volume or monitor changes in internal lesion volume during treatment. If this can be determined via three-dimensional ultrasound, the relative simplicity of the procedure and the decreased cost and known risks to the patient would make this method an attractive alternative to other modalities. METHODS: Three-dimensional ultrasound scans were made of six phantoms: four nonechogenic spheres, one echogenic sphere, and one echogenic, irregularly shaped phantom. A total of 22 volume scans were produced. Volume estimations were made using data from cross-sectional areas and from linear measurements. In all, 193 volume estimations were made. These results were compared with known volumes and with volume estimates from computed tomography scans. RESULTS: Three-dimensional ultrasound detected size differences of 10% with 95% certainty. CONCLUSIONS: The accuracy and precision of volume estimates via three-dimensional ultrasound is at least as good as those obtained via conventional ultrasound.

Humans↗