Effects of extra-renal background subtraction and kidney depth correction in the measurement of GFR by gamma camera renography

Granérus, Göran; Moonen, M.

doi:10.1097/00006231-199106000-00006

Cited by 39 publications

(25 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…One-second images were acquired immediately after the bolus injection of 740 mBq 99 Tc-DTPA during the first minute, followed by 30 images with 1-minute duration. The exams were analyzed visually, and 2 time-activity curves were also generated 22 for the first minute (flow time-activity curve) and for the remaining 30 minutes (function curve). Individual renal relative function was considered abnormal if there was a difference of Ͼ10% between the kidneys.…”

Section: Renal Artery Stenosismentioning

confidence: 99%

Obstructive Sleep Apnea

et al. 2011

View full text Add to dashboard Cite

Abstract-Recognition and treatment of secondary causes of hypertension among patients with resistant hypertension may help to control blood pressure and reduce cardiovascular risk. However, there are no studies systematically evaluating secondary causes of hypertension according to the Seventh Joint National Committee. Consecutive patients with resistant hypertension were investigated for known causes of hypertension irrespective of symptoms and signs, including aortic coarctation, Cushing syndrome, obstructive sleep apnea, drugs, pheochromocytoma, primary aldosteronism, renal parenchymal disease, renovascular hypertension, and thyroid disorders. Among 125 patients (age: 52Ϯ1 years, 43% males, systolic and diastolic blood pressure: 176Ϯ31 and 107Ϯ19 mm Hg, respectively), obstructive sleep apnea (apnea-hypopnea index: Ͼ15 events per hour) was the most common condition associated with resistant hypertension (64.0%), followed by primary aldosteronism (5.6%), renal artery stenosis (2.4%), renal parenchymal disease (1.6%), oral contraceptives (1.6%), and thyroid disorders (0.8%). In 34.4%, no secondary cause of hypertension was identified (primary hypertension). Two concomitant secondary causes of hypertension were found in 6.4% of patients.

show abstract

Section: Renal Artery Stenosismentioning

confidence: 99%

Obstructive Sleep Apnea

et al. 2011

View full text Add to dashboard Cite

show abstract

“…In 5 patients, GFR was calculated from the gamma camera renograms [21]; in 4 of these cases, 99n'Tc-MAG3 clearance had to be converted to the corresponding value for 99mTc-DTPA clearance using the formula described by Granerus et al [22]: DTPA clearance = (MAG3 clearance -40)/2.55.…”

Section: Fig 2 Rrf At E and E? Figures Within Parentheses Denote mentioning

confidence: 99%

Studies on Renal Function in Patients with Cystinuria

Lindell¹,

Denneberg²,

Granérus³

1997

Nephron

Self Cite

View full text Add to dashboard Cite

Total and separate renal functions were evaluated in 40 patients with cystinuria. The average duration of the renal stone disease was 26 years (range 1-53). The patients had been subjected to a stone-preventing regimen composed of increased fluid intake, urinary alkalinization and treatment with a sulphydryl compound, tiopronin or D-penicillamine, for an average of 11.7 years (range 1-24). Urinary cystine concentration was determined regularly to monitor the treatment. All patients were examined with gamma camera renography and an assessment of glomerular filtration rate (GFR), and early and late renographic results could be compared in 30 patients. The early renographic evaluation showed that 43% of binephric patients (13/30) had an abnormal relative renal function (RRF) before the start of the stone-preventing treatment. At the late evaluation, 50% of binephric patients (17/34) had an abnormal RRF, while 30% of all patients (12/40) had a GFR below the age-related normal range. Thirty percent of 74 evaluated kidneys (22/74) had a separate GFR below an estimated age-related normal range. At the late evaluation only 30% of the patients had functionally unaffected kidneys with both normal GFR and bilateral normal renography. There was, however, no case with terminal renal failure. The separate GFR of kidneys with a history of staghorn stones was significantly lower than for kidneys without that special type of stones, but otherwise there was no relationship between renal functional impairment and other estimates of the activity of the renal stone disease. In conclusion, impairment of renal function is common in patients with stone-forming cystinuria. Stone-preventive treatment appears to be effective in preserving renal function. The high frequency of renal functional impairment justifies close surveillance of this group of patients. By renographic examination, unilateral changes in renal function can be detected at an early stage and patients at risk for further deterioration of renal function can be identified.

show abstract

“…Renal plasma flow then was derived from total body PAH clearance corrected for renal fractional extraction of PAH. Split renal function was assessed by " T cdiethylenetriamine pentaacetic acid (DTPA) gamma camera renography 16 before and after 25 mg captopril given orally. In our laboratory this dose has been shown to give moderate blood pressure reduction.…”

Section: Renal Plasma Flowmentioning

confidence: 99%

Norepinephrine overflow and renin pattern of the individual kidney in patients with unilateral renal artery stenosis.

et al. 1991

View full text Add to dashboard Cite

This study was performed to determine divided renal efferent sympathetic nerve activity from kidneys in seven patients with renin-positive, unilateral renal artery stenosis before and 30 minutes after an acute intravenous dose of 125 mg enalaprilaL Renal norepinephrine release was calculated from split renal plasma flow, venoarterial plasma concentration gradients across the kidney, and the fractional extraction of tritiated norepinephrine. All patients had unilateral renin secretion, the affected kidney increasing its plasma renin activity gradient 1.7-fold, whereas no statistically significant change was noted on the contralateral side in response to enalaprilat. Total norepinephrine release to plasma and norepinephrine plasma clearance (assessed by isotope dilution) were similar before and after administration of enalaprilat (approximately 400 ng/min and 1.0 I/min), despite a 26% fall in mean arterial pressure (from 125 mm Hg, /><0.01). Heart rate remained unchanged. After enalaprilat, norepinephrine venoarterial difference increased in the renin-secreting kidney (from 264 to 396, SED=57 pg/ml,p<0.05), whereas it increased only slightly in the contralateral kidney (from 149 to 256, SED=72 pg/mJ, NS). Tritiated norepinephrine extraction fell approximately 25% (/?<0.01) in both kidneys. Thus, renal norepinephrine spillover increased from 49 to 62, SED=9 ng/min (NS) and from 81 to 129, SED=17 ng/min (p<0.05) from the affected and the contralateral kidney, respectively. Hence, in this relatively small study in patients with renovascular hypertension, no evidence for increased renal nerve activity could be observed in the affected kidney, despite its marked renin production. Furthermore, it appears that angiotensin converting enzyme inhibition may influence renal neuronal uptake of norepinephrine, as enalaprilat reduced fractional extraction of norepinephrine. (Hypertension 1991;17:1003-1009) I t generally is believed that the renin-angiotensin system plays an important role in renal hypertension.1 -2 The involvement of the sympathetic nervous system, however, is less clear. Direct recording of muscle sympathetic nerve activity has been reported to be elevated in patients with renal artery stenosis compared with controls.3 This increase was normalized after percutaneous transluminal angioplasty on the affected renal artery.3 Although increased muscle sympathetic nerve activity may prevail in renovascular hypertension, 3 the possible involvement of the renal nerves is less clear.Studies of the sympathetic nervous system by measurements of norepinephrine (NE) have yielded increased levels of NE in the renal vein both during resting conditions 4 and in response to acute blood pressure reduction by hydralazine in patients with unilateral renal artery stenosis. 56 Moreover, Gordon et al 7 showed increased levels of NE in left adrenal vein in humans with renal hypertension on the basis of renal artery stenosis. These findings have been taken as evidence for an increased renal sympathetic nerve activity. 56 The experim...

show abstract

Effects of extra-renal background subtraction and kidney depth correction in the measurement of GFR by gamma camera renography

Cited by 39 publications

References 0 publications

Obstructive Sleep Apnea

Obstructive Sleep Apnea

Studies on Renal Function in Patients with Cystinuria

Norepinephrine overflow and renin pattern of the individual kidney in patients with unilateral renal artery stenosis.

Contact Info

Product

Resources

About