PubMed Health⌕ Search

Biomedical subjects

H Y Oei

Publications and source records attributed to H Y Oei.

At least 55 records · Page 3Linked to original sources
PubMed1987

The hot skull: malignant or feminine?

Diffusely increased uptake in the calvarium on bone scintigraphy (a hot skull) is often present in patients with bone metastases and metabolic diseases. Excluding these known facts the prevalence of the hot skull and its relation with malignancy and, more specifically, with breast carcinoma have been studied in 673 patients. In women, the hot skull is clearly related to malignancy and to a lesser extent to breast carcinoma. However, another remarkable feature of the hot skull is its predominance in women in general (compared to men) and, therefore, the data suggest that the hot skull can also represent a normal variant of the female skull. We conclude that the hot skull has no clinical value in screening protocols.

Bone and Bones↗
PubMed1987

Renovascular hypertension identified by captopril-induced changes in the renogram.

Radioisotope renography was performed in 21 patients with hypertension and unilateral renal artery stenosis with and without premedication with 25 mg of captopril, and the results were compared with the effect of percutaneous transluminal angioplasty on the blood pressure, assessed 6 weeks after angioplasty. Angioplasty caused a considerable decrease in blood pressure in 15 of the 21 patients. In 12 of these 15 patients, captopril induced changes in the time-activity curves of the affected kidney only, suggesting deterioration of the excretory function of that kidney, while the function of the contralateral kidney remained normal. After angioplasty the asymmetry in the time-activity curves diminished despite identical pretreatment with captopril. Such captopril-induced unilateral impairment of the renal function was not seen in the six patients with unilateral renal artery stenosis whose blood pressure did not change after percutaneous transluminal angioplasty or in 13 patients with hypertension and normal renal arteries. The functional impairment of the affected kidneys was characterized by a decrease of 99mTc-diethylenetriamine pentaacetic acid uptake and a delay of 131I-hippurate excretion, while the 131I-hippurate uptake remained unaffected. These data are in agreement with a reduced glomerular filtration rate and diuresis during preservation of the renal blood flow, changes that can be expected after converting enzyme inhibition in a kidney with low perfusion and an active, renin-mediated autoregulation of the glomerular filtration rate. These data suggest that functional captopril-induced unilateral changes, shown by split renal function studies with noninvasive gamma camera scintigraphy, can be used as a diagnostic test for renovascular hypertension caused by unilateral renal artery stenosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1987

Gastric emptying and postprandial symptoms after Billroth II resection.

Gastric emptying was studied in 18 symptomatic and 16 asymptomatic patients after Billroth II (BII) resection (without vagotomy) and the possible relationships between emptying and postprandial symptoms in these patients were assessed. The BII patients were compared with 20 nonoperated patients who had duodenal ulcer disease and 16 healthy subjects. Gastric emptying of two test meals (a semisolid porridge meal and a solid pancake meal) was measured with a radionuclide technique. The major difference between the BII patients and control subjects and duodenal ulcer patients was an increased rate of emptying of the semisolid meal in the first 5 minutes after meal consumption. The percentage of the meal remaining in the stomach at 5 minutes after completion was significantly less in the symptomatic (45.3% +/- 4.3%) than in the asymptomatic BII patients (79.4% +/- 2.6%). A positive correlation was demonstrated between the initial emptying rate of semisolids and the intensity of postprandial nausea (p less than 0.01), vomiting (p less than 0.05), and vasomotor symptoms (p less than 0.001). The duration of the lag phase for solid and semisolid meals was shorter in BII patients than in healthy subjects but was as short in nonoperated duodenal ulcer patients. The duration of the lag phase for solid food in the BII patients correlated positively with the score for postprandial epigastric pain (p less than 0.001). The rate of emptying of the solid meal was lower in symptomatic BII patients (28.1% +/- 3.6% per hour) than in asymptomatic patients (47.8% +/- 7.2% per hour) and correlated with the severity of postprandial fullness and nausea. The emptying of the solid meal was inversely related to the initial emptying rate of the semisolid meal (p less than 0.05). Therefore, the results of this study support the assumption that many of the postprandial symptoms occurring after BII resection reflect alterations in gastric emptying. Some of the emptying abnormalities present after BII resection may be related to duodenal ulcer disease rather than to the surgical procedure.

Adolescent↗
PubMed1986

Renography with captopril. Changes in a patient with hypertension and unilateral renal artery stenosis.

In a 56-year-old man with severe familial hypertension and unilateral renal artery stenosis, captopril induced striking changes in the renograms of the affected kidney. After injection of orthoiodohippurate sodium I 131, the uptake phase was unchanged but the later curve showed continuous accumulation. In contrast, the uptake of technetium Tc 99m diethylenetriamine pentracetic acid was abolished. These changes are compatible with a cessation of filtration and maintenance of renal blood flow. After balloon dilatation of the stenosis, the blood pressure became lower, and these changes could no longer be demonstrated. The captopril renogram may provide useful information on the dependency of hypertension on unilateral renal artery stenosis.

Captopril↗
PubMed1986

Hemodynamics of the varicocele. Part I. Correlation among the clinical, phlebographic and scintigraphic findings.

To determine whether the varicocele results from collateral circulation partially replacing an obstructed left renal vein, we developed a scintigraphic technique that provides not only information about the velocity of retrograde flow in the testicular veins but also quantitative information about the size of the varicocele. The reliability of this method was assessed by comparison with the results of phlebography and the clinical diagnosis in 104 patients. Furthermore, the diameter of the left testicular vein was determined on the phlebogram. Good correlation was found among the velocity of the retrograde flow in the left testicular vein, the size of the varicocele and the diameter of the left testicular vein.

Collateral Circulation↗
PubMed1986

Hemodynamics of the varicocele. Part II. Correlation among the results of renocaval pressure measurements, varicocele scintigraphy and phlebography.

Left renal vein compression occurring mainly with the patient in the upright position, and being less severe or absent in the supine position, was considered to be the main cause of varicoceles. We show that left renal vein compression is, indeed, more severe with the patient in the upright than in the supine position and that it produces a left renocaval pressure gradient that is responsible for the retrograde blood flow in the left testicular vein. This pressure gradient, which was determined in the supine and semierect positions in 34 patients, increased from a mean of 3.8 mm. Hg in the supine position to a mean of 7.8 mm. Hg in the semierect position. On the basis of the assumption that the renocaval pressure gradient measured with the patient in the semierect position determines the presence and velocity of a retrograde flow in the left testicular vein, as shown by the dynamic portion of the varicocele scintigram (see part I), these variables were analyzed and the correlation coefficient proved to be good. Therefore, we conclude that the varicocele occurs when the left testicular vein lacks valves or there is a renogonadal bypass, and the severity of the left renal vein compression in the (semi) upright position determines the velocity of the retrograde flow in the left testicular vein and the size of the varicocele.

Blood Pressure↗
PubMed1986

Renography: prediction of blood pressure after dilatation of renal artery stenosis.

In 60 patients with hypertension and unilateral renal artery stenosis (URAS) radio-hippuran renograms were performed before and 6 weeks after anatomically adequate percutaneous transluminal angioplasty (PTA). Two characteristics of the renographic curves have been analyzed: the difference in time to peak (DTP) between the affected and contralateral kidneys, which would be expected to be positive in blood flow impairment, and the relative hippuran uptake (RHU) in the second minute by the affected kidney as compared with the total uptake by both kidneys: this would be less than 50% in the case of stenosis. Before PTA, both variables were predominantly abnormal. The DTP did not predict the blood pressure response to PTA. The group of patients with a RHU between 25 and 45% comprised all cured patients and predicted a more favorable response of the blood pressure than a RHU of less than 25% and especially more than 45% which group contained 83% patients whose blood pressure failed to respond after PTA. After PTA the DTP did normalize in the majority of patients, but this was not related to the blood pressure response. The RHU increased in patients in whom it had been low initially, but frequently remained low (less than 45%). The increase of the RHU was significantly higher in patients with a favorable blood pressure response. Pretreatment with captopril did intensify the abnormal curves of hippuran and of DTPA renograms in 6 patients with URAS who did respond favorably to PTA. There was no such deterioration in 2 patients whose blood pressure did not change sufficiently after PTA or in 4 patients without renal artery stenosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Angioplasty, Balloon↗
PubMed1984

Haemodynamic aspects of left-sided varicocele and its association with so-called right-sided varicocele.

A method has been developed which uses a radionucleotide to demonstrate retrograde bloodflow in the testicular vein and the size of the pampiniform plexus in patients with a varicocele. This method and phlebography were both performed in 71 patients. The radionucleotide method was reliable in showing retrograde flow in the testicular vein and enabled quantification of the size of the pampiniform plexus. On the right side, however, retrograde bloodflow or an enlarged pampiniform plexus were not found in any of the 71 patients. Misinterpretation of phlebographic and radionucleotide studies are probably responsible for recent reports on the frequent occurrence of right sided varicocele.

Humans↗
PubMed1984

Radionuclide measurement of normal and disturbed gastric motility.

Techniques for the measurement of gastric emptying using radionuclides are reviewed as a basis for a discussion of gastric emptying tests. A new technique for the noninvasive quantitative measurement of antral motility is described, whereby measurements of redistribution of gastric contents between fundus and antrum and actual gastric emptying are obtained simultaneously. These tests provide more relevant insight into the pathophysiology of gastric motility disturbances than that previously obtained by conventional gastric emptying studies.

Duodenal Ulcer↗
PubMed1983

Follow up study of 70 patients with renal artery stenosis treated by percutaneous transluminal dilatation.

Between April 1978 and April 1981, 70 patients with hypertension and renal artery stenosis were treated by percutaneous transluminal arterial dilatation. Selection of the patients was based solely on arteriographic criteria. Arteriography after dilatation showed considerable widening of the stenosed area in all patients. In 65 patients the effect of treatment on the blood pressure was assessed during follow up periods of one to four years. In 14 of these patients the hypertension was cured, in 29 it was improved, and in 22 there was no change. Patients with fibromuscular lesions benefited distinctly more than did those with atheromatous stenosis, only one of the 21 patients with fibromuscular lesions showing no change as compared with 21 of the 44 patients with atheromatous lesions. The only serious complication encountered was microcholesterol emboli, which developed in two patients with severe atheromatous lesions of the aorta. In the atheromatous group age and overall renal function had no influence on the blood pressure response. In the subgroup of patients with a unilateral lesion the renal vein renin ratios and asymmetrical curves obtained by renography had only a very limited predictive value. In experienced hands percutaneous transluminal arterial dilatation is relatively safe, and this study suggests that it should be attempted in all patients with renal artery stenosis. Only in patients with severe atheromatosis of the aorta should the risk associated with the catheterisation be weighed against the 50% or so chance of benefit from the procedure.

Adult↗
PubMed1983

The predictive value of hippuran uptake in acute renal failure.

In this study the hippuran uptake capacity (HUC) in 32 patients with an acute deterioration of renal function was measured. The HUC2 is the ratio between the activity accumulated in the kidneys in the first two minutes, divided by the injected dose, which was measured by the gammacamera, during standardised renography. Thirteen patients had an acute glomerular disease (AGD) and 19 patients had acute tubular necrosis (ATN). During the acute deterioration of renal function, the HUC2 values ranged between 0 and 3.0 in the AGD group and between 1.9 and 8.7 in the ATN group. In only one patient of this latter group was the HUC2 value below three. Measurement of HUC2 is useful in the differential diagnosis of acute renal failure. It can be performed in the absence of urine production and indicates renal blood perfusion despite complete absence of filtration. When the HUC2 value is higher than three, ATN is the most probable aetiology of the acute renal failure and recovery of renal function can be expected. Values below this limit most probably indicate AGD.

Acute Kidney Injury↗
PubMed1982

Renal clearance of [14C]oxalate: comparison of constant-infusion with single-injection techniques.

1. The renal clearance of [14C]oxalate was assessed by the constant-infusion technique and single-injection technique (plasma sampling only: one-compartment and two-compartment model; plasma and urine sampling). Healthy volunteers and patients with renal stones were studied. 2. Results with the constant-infusion techniques (with and without urine sampling) were not significantly different from each other. 3. The renal clearance of [14C]oxalate measured with the single-injection technique as compared with the constant-infusion technique was overestimated in the single-injection one-compartment model (52%) as well as in the two-compartment model (30%). 4. The calculated level of plasma oxalate in the healthy volunteers ranged from 1.04 to 1.78 mumol/l (mean 1.39). 5. The biological half-life of [14C]oxalate, estimated by the cumulative excretion of 14C in urine after equilibrium had been established, was 128 min (range: 113-142). 6. The oxalate/creatinine clearance ratio in the healthy volunteers ranged from 1.73 to 2.22 (mean 2.01).

Female↗
PubMed1981

Determination of glomerular filtration rate by 111In-DTPA.

To evaluate the use of 111indium-diethylenetriamine pentaacetic acid (111In-DTPA) for determination of the glomerular filtration rate (GFR), the results of 60 standard 111In-DTPA clearances were compared with 24-h urine endogenic creatinine clearances obtained on 3 successive days (r = 0.97, P less than 0.001) and with endogenic creatinine clearances obtained during 111In-DTPA determinations (r = 0.93, P less than 0.0001). It is concluded that 111In-DTPA is a useful marker for GFR.

Creatinine↗
PubMed1979

Intraluminal dilatation of renal artery stenosis.

1. In 13 patients with hypertension and renal artery stenosis the stenosis was dilated by an intra-arterial balloon catheter under local anaesthesia. 2. In all but one instance arteriography after the dilatation showed considerable widening of the stenosed area. 3. Six patients had a temporary increase of serum creatinine that lasted only a few days. 4. In seven patients, who had a prolonged transit time at renography, this marker of renal blood flow improved after the dilatation. 5. The effect of the dilatation on the blood pressure in this group of patients, selected on arteriographic criteria only, was variable, but comparable with results of renovascular surgery. 6. Dilatation of renal artery stenosis by an intra-arterial balloon catheter is a promising treatment for patients with hypertension and renal artery stenosis. It is a rapid procedure needing only local anaesthesia. Complications in our experience so far are minor.

Adult↗