Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Petrosal Sinus Sampling”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources

Neurologic complications of petrosal sinus sampling.

Petrosal sinus sampling has been described as an innocuous, essentially risk-free procedure. The authors report on two patients from two different institutions who sustained brain stem injury as a result of petrosal sinus sampling and two other patients in whom brain stem injury was avoided. Major neurologic complications have occurred in only 0.2% of procedures (one of 508) performed at the National Institutes of Health and in 0.5% of a subset of these procedures (one of 184) that were performed with a specially designed petrosal sinus catheter. The cause of these complications is unclear but is presumed to be localized venous hypertension. Tip-deflector catheter-guide-wire systems, if available, are recommended for petrosal sinus sampling. Inadequate data exist to permit recommendation of any other catheter. Brain stem injury is preventable if the catheter is withdrawn at the earliest sign of even a minor, seemingly insignificant problem. Subtle symptoms and signs that may not appear to be neurologic may herald a clinical catastrophe if not heeded.

Adult↗

Raymond's syndrome following petrosal sinus sampling.

Inferior petrosal sinus sampling (IPSS) is used to evaluate the pituitary-dependency of Cushing's disease, and to predict the laterality of a microadenoma prior to transsphenoidal operation. A serious complication occurred in a 14-year-old boy: he suffered brain stem ischaemia with abducens nerve palsy and hemiparesis (Raymond's syndrome). The case prompted us to reconsider the indication for this investigation.

Abducens Nerve↗

Diagnostic errors after inferior petrosal sinus sampling.

Although inferior petrosal sinus sampling (IPSS) is useful in the evaluation of Cushing's syndrome, false negative cases have been described, and many patients presumed to have ectopic tumors based upon negative IPSS remain without a final diagnosis. These patients are often managed as if they have as yet undiscovered ectopic tumors. To test this assumption, we conducted a retrospective review of our results to determine the ultimate diagnoses after IPSS. Between 1986 and 2002, 179 patients underwent 185 IPSS procedures as part of their evaluation for Cushing's syndrome. Confirmed diagnoses were available for 149 patients (83%): 139 patients had pituitary adenomas (94%), eight had bronchial carcinoids (5%), and two had adrenal tumors (1%). Threshold criteria for a pituitary source were defined as an inferior petrosal sinus to peripheral (IPS:P) basal ratio of 2:1 or greater without CRH or an IPS:P ratio of 3:1 or greater after CRH stimulation. There were nine patients in whom the IPS:P ratio failed to meet threshold criteria after successful sampling, but were nonetheless found to have pituitary tumors after transsphenoidal exploration (false negatives). Eight of these had received CRH and had a significant rise (>35%) in peripheral ACTH levels after CRH treatment, even though the IPS:P ratio did not reach the threshold. There were two patients in whom the IPS:P ratio reached threshold criteria, and ectopic tumors were demonstrated as the source of ACTH overproduction (false positives). The sensitivity after CRH stimulation was 90% (95% confidence interval, 80.8-95.5%) with a specificity of 67% (95% confidence interval, 11.4-94.5%). The positive and negative predictive values were 99 and 20%, respectively. Our data show that patients with an IPS:P ratio suggestive of a nonpituitary source of ACTH overproduction may still have Cushing's disease. Analyzing the CRH-stimulated peripheral ACTH levels in addition to the standard IPS:P ratios may provide improved diagnostic accuracy. Transsphenoidal exploration should be considered in all cases of unsuccessful sampling and in those cases for which no ectopic source can be identified after further body imaging, even if the IPSS is negative, and especially if peripheral ACTH levels rise significantly with CRH stimulation.

Adolescent↗

The diagnosis of acromegaly: value of inferior petrosal sinus sampling.

The early diagnosis of acromegaly may be difficult when serum levels of growth hormone are minimally elevated and imaging of the pituitary gland fails to show an adenoma. However, transsphenoidal surgery has the greatest chance of cure at this stage. We therefore investigated the value of sampling petrosal sinuses for measurement of growth hormone in this group of patients. Simultaneous bilateral sampling of the inferior petrosal sinuses to measure serum concentrations of growth hormone was performed in five patients suspected of having acromegaly but with nondiagnostic CT scans (n = 5) and MR images (n = 3) of the pituitary gland. Levels of growth hormone from the petrosal sinuses were five to 36 times greater than levels in the peripheral veins in all five patients, and three of four showed a marked response to growth hormone-releasing hormone. During transsphenoidal surgery, growth hormone-producing microadenomas were resected completely in four patients. In the fifth patient, a left-sided microadenoma had invaded the cavernous sinus and could not be resected completely. Lateralization of the adenomas within the pituitary gland on the basis of differences in levels of growth hormone between the two petrosal sinuses was not completely reliable. Elevated levels of growth hormone in selective samples from the inferior petrosal sinuses can help support an early diagnosis of acromegaly when peripheral growth hormone levels and imaging are not diagnostic.

Acromegaly↗

Cavernous and inferior petrosal sinus sampling in the evaluation of ACTH-dependent Cushing's syndrome.

OBJECTIVE: Central venous sampling (CVS) is used frequently in the evaluation of ACTH-dependent Cushing's syndrome. However, several controversies exist including the diagnostic accuracy, the sampling site of choice (cavernous sinus vs. inferior petrosal sinus) and the use of lateralization data in tumour localization. We have analysed our experience with CVS to address these controversies. DESIGN: We retrospectively reviewed CVS data in patients with ACTH-dependent Cushing's syndrome, in whom cavernous sinus sampling (CSS), inferior petrosal sinus sampling (IPSS) and IPSS after administration of ovine corticotrophin releasing hormone (oCRH) were performed. PATIENTS: Data on 95 patients were analysed, including 79 patients with suspected Cushing's disease (CD) and 16 patients with suspected ectopic ACTH syndrome (EAS). RESULTS: For the differential diagnosis of ACTH-dependent Cushing's syndrome, the diagnostic accuracy of IPSS after oCRH stimulation was 97% compared to 86% for CSS. While no single sampling site was perfect in diagnostic accuracy, sampling both CS and IPS achieved a combined diagnostic accuracy of 100%. Lateralization data predicted tumour location in 62-68% of the patients with various central venous drainage patterns and in 77-80% of the patients with symmetrical drainage. CSS was not significantly superior to IPSS in tumour lateralization. In patients with suspected CD based on CVS and in whom an adenoma was not found on magnetic resonance imaging (MRI) and not located by the surgeon intraoperatively, hemihypophysectomy based on lateralization data was successful in only 10 of the 18 patients (56%) with various central venous drainage patterns and in 5 of 10 patients with symmetrical drainage. CONCLUSION: CVS is a powerful method for differentiating CD from the EAS. CSS without oCRH was not superior to IPSS after oCRH stimulation; however, we achieved a 100% diagnostic accuracy if at least two sites were sampled. Tumour localization by CVS did not accurately predict the tumour site at surgery and should not be used to guide surgical resection.

ACTH Syndrome, Ectopic↗

Naloxone stimulation of ACTH secretion during petrosal sinus sampling in Cushing's syndrome.

1. Petrosal sinus sampling has been used to establish the source of adrenocorticotropin (ACTH) in ACTH-dependent Cushing's syndrome. Naloxone, an opioid antagonist, stimulates ACTH secretion, probably via release of endogenous hypothalamic corticotropin releasing hormone (CRH). 2. Three patients with hypercortisolism were studied. Two showed suppressed (> 50%) urinary-free cortisol excretion with high-dose dexamethasone treatment (2 mg every 6 h for 2 days), one did not suppress. The patients were subjected to bilateral simultaneous inferior petrosal sinus sampling (BSIPSS) with simultaneous peripheral venous (forearm) samples. Basal (unstimulated) samples were taken and naloxone (125 micrograms/kg bodyweight) was given intravenously with subsequent simultaneous sampling. Plasma ACTH was measured by radio-immunoassay (RIA). 3. All cases exhibited a marked rise in immunoreactive (IR)-ACTH levels (pmol/L) after naloxone injection, basal to peak: case 1, left 11.5-22.1, right 9.8 with no rise, peripheral 9.1-9.5; case 2, left 456-863, right 125-501, peripheral 59-82; case 3, left 12.7-13.0, right 277-431, peripheral 12.1-11.7. All results indicate pituitary Cushing's syndrome, with a central to peripheral ratio > 2.3:1. Pituitary Cushing's syndrome was confirmed on the results of trans-sphenoidal pituitary surgery in cases 1 and 3. 4. It is suggested that naloxone injection during petrosal sinus sampling in Cushing's syndrome may assist in the diagnosis of ACTH source, by enhancing ACTH release from a pituitary micro-adenoma.

Adrenocorticotropic Hormone↗

Jugular venous sampling: an alternative to petrosal sinus sampling for the diagnostic evaluation of adrenocorticotropic hormone-dependent Cushing's syndrome.

Bilateral sampling of the inferior petrosal sinuses (IPSS) to distinguish Cushing's disease from the ectopic ACTH syndrome is accurate but risky and technically difficult. Bilateral sampling of the internal jugular vein (JVS) is simpler and presumably safer. To compare jugular and petrosal sinus venous sampling for distinguishing Cushing's disease from ectopic ACTH syndrome, we studied 74 patients with surgically proven Cushing's disease, 11 with surgically confirmed, and three with occult ectopic ACTH secretion. Patients underwent JVS and IPSS with administration of CRH on separate days. Ratios of central-to-peripheral ACTH in venous samples were calculated. At 100% specificity, IPSS correctly identified 61 of 65 patients with Cushing's disease [sensitivity, 94%; confidence interval (CI), 84-98%]. When patients with abnormal venous drainage were excluded, sensitivity was 98% (CI, 90-100%). JVS had a sensitivity of 83% (CI, 71-91%) at 100% specificity. Receiver operated characteristics plot areas under the curve were similar (0.968 +/- 0.020 and 0.974 +/- 0.016, area under the curve +/- se, JVS vs. IPSS). Although petrosal sampling had better diagnostic accuracy, CIs overlapped (95% CI, 90-100% vs. 86% CI, 78-94%). Centers with limited sampling experience may choose to use the simpler JVS and refer patients for IPSS when the results are negative.

ACTH Syndrome, Ectopic↗

Internal jugular vein sampling in adrenocorticotropic hormone-dependent Cushing's syndrome: a comparison with inferior petrosal sinus sampling.

OBJECTIVE: Distinguishing between pituitary-dependent Cushing's syndrome (CS) and occult ectopic ACTH syndrome can be extremely difficult. Bilateral inferior petrosal sinus sampling has been shown to have the highest diagnostic accuracy in this subtype evaluation. Internal jugular vein sampling (IJVS) has been reported as a potentially safer invasive alternative, but data are limited. Our objective was to compare the sensitivity and specificity of bilateral IJVS and bilateral inferior petrosal sinus sampling (IPSS) in patients with ACTH-dependent CS. DESIGN: We prospectively collected blood samples from the inferior petrosal sinus and internal jugular vein of consecutive patients with ACTH-dependent CS. PATIENTS: The study group included 35 patients: 32 with pituitary-dependent CS (positive immunohistochemical findings for ACTH pituitary tumour or biochemical cure after pituitary surgery) and three with histologically proven ectopic ACTH syndrome. MEASUREMENTS: Inferior petrosal sinus sampling and bilateral IJVS were performed simultaneously before and after administration of corticotropin-releasing hormone (CRH), and ratios of central-to-peripheral ACTH concentrations were calculated. RESULTS: The basal IJVS central-to-peripheral ACTH ratios were diagnostic for pituitary-dependent CS (> 2) in 15 patients (46.9%), as were basal inferior petrosal sinus sampling central-to-peripheral ACTH ratios in 29 patients (90.6%). The post-CRH IJVS central-to-peripheral ACTH ratios were diagnostic for pituitary-dependent disease (> 3) in 24 patients (75%), as were post-CRH inferior petrosal sinus sampling central-to-peripheral ACTH ratios in 28 patients (87.5%). In the three patients with ectopic ACTH CS, the IJVS and inferior petrosal sinus sampling pre- and post-CRH ACTH ratios were correctly negative. The overall sensitivity of combined pre- or post-CRH was 81.3% for IJVS and 93.8% for inferior petrosal sinus sampling. Because of the difference between mean ratios in the two techniques, new criteria for IJVS were mathematically calculated: a pre-CRH central-to-peripheral ACTH ratio of 1.59 and a post-CRH central-to-peripheral ACTH ratio of 2.47 maximized sensitivity and specificity when both of these are equally taken into consideration. CONCLUSION: In conclusion, IJVS is not superior to inferior petrosal sinus sampling for establishing the cause of ACTH-dependent CS. When new criteria of basal (> 1.6) and post-CRH (> 2.5) central-to-peripheral ACTH gradients were applied to ACTH ratios from IJVS, the sensitivity of this test was maximized. However, confirmatory inferior petrosal sinus sampling is recommended when there is a lack of a central-to-peripheral ACTH gradient and when there is only a gradient above the cut-off on basal (pre-CRH) sampling.

ACTH Syndrome, Ectopic↗

Venous thrombo-embolism following inferior petrosal sinus sampling in Cushing's disease.

Bilateral inferior petrosal sinus sampling for ACTH with corticotrophin releasing hormone stimulation has become an established test in differentiating pituitary Cushing's disease from Cushing's syndrome due to ectopic ACTH secretion. We report two patients with Cushing's disease who developed thromboembolic complications soon after inferior petrosal sinus sampling. We discuss the possible mechanisms leading to this complication in a syndrome in which thromboembolic complications are well recognized and highlight the need for consideration of prophylactic anticoagulation.

Adenoma↗

Bilateral sequential inferior petrosal sinus sampling with corticotrophin-releasing hormone stimulation in the diagnosis of Cushing's disease.

OBJECTIVE: The demonstration of a central to peripheral ACTH gradient in a hypercortisolaemic patient is diagnostic of Cushing's disease. We tried to determine whether single blood samples for ACTH obtained sequentially from each of the inferior petrosal sinuses following human corticotrophin-releasing hormone (hCRH) stimulation can reliably establish such a gradient. DESIGN: Prospective study. PATIENTS: Seventeen patients with clinical and biochemical features of Cushing's syndrome. METHODS: After the administration of hCRH, the patients underwent bilateral sequential inferior petrosal sinus sampling, with a single blood sample obtained from each of the inferior petrosal sinuses sequentially, along with a peripheral venous sample. The petrosal sinus catheter was withdrawn immediately after obtaining a blood sample. Patients did not require indwelling catheters in the petrosal sinuses, nor heparinisation. RESULTS: Bilateral sequential inferior petrosal sinus sampling correctly identified a pituitary source of ACTH, as shown by a central to peripheral ACTH ratio >2, in all patients in whom the procedure was successfully carried out. All patients underwent transsphenoidal pituitary surgery resulting in remission. CONCLUSIONS: The simplified method of inferior petrosal sinus sampling, using a single sequential sample from each of the inferior petrosal sinuses, following initial hCRH stimulation, is as accurate as the more complex test using multiple bilateral simultaneous inferior petrosal sinus samples. It avoids the use of indwelling cerebral venous catheters and is therefore unlikely to cause brain stem damage.

Adult↗

Venous subarachnoid hemorrhage after inferior petrosal sinus sampling for adrenocorticotropic hormone.

Neurologic complications associated with inferior petrosal sinus sampling for adrenocorticotropic hormone in the diagnosis of Cushing syndrome are rare. Previously reported complications include brain stem infarction and pontine hemorrhage. We report a case of venous subarachnoid hemorrhage with subsequent acute obstructive hydrocephalus occurring during inferior petrosal sinus sampling for Cushing syndrome.

Adrenocorticotropic Hormone↗

Is whole-lung CT scanning still necessary in all cases of ACTH-dependent Cushing's syndrome in the era of petrosal sinus sampling?

We reviewed 31 patients in whom both bilateral inferior petrosal sinus sampling without CRH stimulation, and a CT scan of the lungs were done. Twenty-five had normal lung CT scans, of whom 23 had a higher inferior petrosal sinus: peripheral ACTH ratio > or = 1.5. After careful follow-up, none was subsequently shown to have ectopic ACTH syndrome. Six had abnormal lung CT scans, of whom two had ratios > or = 1.5. In these two patients, other investigations suggested pituitary disease, and pituitary surgery led to apparent cure. Of the remaining four patients, who had ratios < 1.5, two had incidental lung findings, and pituitary abnormalities were demonstrated at pituitary surgery. The third underwent bilateral adrenalectomy, and no evidence of ectopic ACTH syndrome has emerged as yet after 4 years follow-up. The fourth had a small-cell carcinoma of the lung, confirmed histologically. Our series suggests that whole-lung CT scanning is only necessary in cases of ACTH-dependent Cushing's syndrome where bilateral inferior petrosal sinus sampling has not demonstrated a significant increase in petrosal sinus ACTH levels as compared with the peripheral level. Thus, in our experience the test is now only necessary in those patients (approximately 25%) where the ratio is < or = 1.5.

ACTH Syndrome, Ectopic↗

Identification of patients with Cushing's disease with negative pituitary adrenocorticotropin gradients during inferior petrosal sinus sampling: prolactin as an index of pituitary venous effluent.

Inferior petrosal sinus sampling for ACTH differentiates pituitary ACTH-dependent Cushing's (CD) from the ectopic ACTH syndrome (EAS). Petrosal sinus to peripheral (IPS:P) ACTH ratios greater than 2.0 in the basal state or a peak greater than 3.0 after CRH are diagnostic of CD. However, false-negative rates of 1-10% have been reported. We report three patients with features of CD with peak IPS:P ACTH ratios less than 3.0 after CRH suggesting EAS. We compared IPS:P prolactin (PRL) as an index of pituitary venous effluent in these three index cases with 44 patients with CD and five with EAS. The dominant basal IPS:P PRL ratio was greater than 1.8 in all 49 patients but was less than 1.2 in the three index cases. The IPS:P ACTH ratio normalized to IPS:P PRL was greater than 0.8 in all CD patients but was less than 0.6 in EAS patients. The IPS:P ACTH ratios normalized to IPS:P PRL were greater than 1.2 in the index cases, which was similar to those with CD. The three index cases had clinical and biochemical remissions after pituitary surgery.PRL is an index of pituitary venous effluent during inferior petrosal sinus sampling in patients with CD who fail to have a peak IPS:P ACTH ratio greater than 3.0 after CRH. IPS:P PRL should be measured when results indicate EAS.

ACTH Syndrome, Ectopic↗

The application of a combined stimulation with CRH and desmopressin during bilateral inferior petrosal sinus sampling in patients with Cushing's syndrome.

BACKGROUND: Bilateral inferior petrosal sinus sampling (BIPSS) is a useful investigative technique in the differential diagnosis of ACTH-dependent Cushing's syndrome (CS). The diagnostic sensitivity of this procedure is improved by the administration of CRH to stimulate ACTH secretion. It has been reported recently that the combined administration of CRH and desmopressin is a more potent stimulus for ACTH release from corticotroph adenomas. We therefore hypothesized that the combined stimulation of ACTH secretion with CRH plus desmopressin may further improve the diagnostic outcome of this procedure. AIMS: To report our experience of the application of combined stimulation with CRH and desmopressin during BIPSS in patients with ACTH-dependent Cushing's syndrome, and to compare these results to those obtained in patients who have undergone BIPSS with CRH stimulation alone. PATIENTS: We studied 34 patients with ACTH-dependent CS: 30 with Cushing's disease (CD) and four with occult ectopic ACTH syndrome (oEAS). A combined stimulation with CRH (100 micrograms i.v.) plus desmopressin (10 micrograms i.v.) during BIPSS was performed in 15 patients with CD, while in a different group of 15 patients with CD, BIPSS was performed with CRH stimulation alone (100 micrograms i.v.). In the patients with oEAS, BIPSS was performed with CRH stimulation in three and CRH plus desmopressin in one patient. RESULTS: In patients with CD the mean peak ACTH levels from the dominant petrosal sinus samples were significantly higher in the group given a combined stimulus than in the group who had only CRH stimulation (mean +/- SD: 1649 +/- 938 vs. 692 +/- 561 ng/l, P < 0. 05). Dominant inferior petrosal sinus/peripheral (IPS/P) ACTH ratios greater than 2 were observed in 15/15 (100%) patients following the combined stimulation with CRH and desmopressin and 13/15 (87%) patients undergoing stimulation with CRH alone. No patient with oEAS had an IPS/P ratio greater than 2. It is of note that the single patient with oEAS studied following a combined stimulation during BIPSS had a IPS/P ratio of less than 2, despite a significant peripheral ACTH and cortisol response. CONCLUSIONS: A combined stimulus using CRH and desmopressin appears to induce a higher ACTH output from pituitary corticotroph adenomas during BIPSS, which may improve the diagnostic sensitivity of this procedure.

Adenoma↗

Bilateral inferior petrosal sinus sampling as a routine procedure in ACTH-dependent Cushing's syndrome.

Bilateral inferior petrosal sinus sampling was successfully performed in 12 of 13 consecutive patients with ACTH-dependent Cushing's syndrome. Ten of the patients subsequently had transsphenoidal pituitary microsurgery. Eight patients in whom the inferior petrosal sinus to peripheral vein ACTH level ratio was 1.5 or greater were found to have a pituitary adenoma. One of the remaining two patients who had ratios less than 1.5 had pituitary hyperplasia while the other had no identified abnormality. In five of the patients with pituitary tumour a ratio above 1.5 was present on only one side. Bilateral petrosal sampling is therefore always necessary. Tumour localization within the pituitary was only poorly predicted by either petrosal sinus sampling (four of eight) or computed tomography scanning (three of eight). If petrosal sinus sampling is used early in the differential diagnosis of ACTH-dependent hypercortisolism, then the use of other differential diagnostic tests may not always be necessary.

Adenoma↗

Petrosal sinus sampling: technique and rationale.

Bilateral simultaneous sampling of the inferior petrosal sinuses is an extremely sensitive, specific, and accurate test for diagnosing Cushing disease and distinguishing between that entity and the ectopic ACTH syndrome. It is also valuable for lateralizing small hormone-producing adenomas within the pituitary gland. The inferior petrosal sinuses connect the cavernous sinuses with the ipsilateral internal jugular veins. The anatomy of the anastomoses between the inferior petrosal sinus, the internal jugular vein, and the venous plexuses at the base of the skull varies, but it is almost always possible to catheterize the inferior petrosal sinus. In addition, variations in size and anatomy are often present between the two inferior petrosal sinuses in a patient. Advance preparation is required for petrosal sinus sampling. Teamwork is a critical element, and each member of the staff should know what he or she will be doing during the procedure. The samples must be properly labeled, processed, and stored. Specific needles, guide wires, and catheters are recommended for this procedure. The procedure is performed with specific attention to the three areas of potential technical difficulty: catheterization of the common femoral veins, crossing the valve at the base of the left internal jugular vein, and selective catheterization of the inferior petrosal sinuses. There are specific methods for dealing with each of these areas. The sine qua non of correct catheter position in the inferior petrosal sinus is demonstration of reflux of contrast material into the ipsilateral cavernous sinus. Images must always be obtained to document correct catheter position. Special attention must be paid to two points to prevent potential complications: The patient must be given an adequate dose of heparin, and injection of contrast material into the inferior petrosal sinuses and surrounding veins must be done gently and carefully. When the procedure is performed as outlined, both inferior petrosal sinuses can be catheterized in more than 98% of patients. The complication rate is low, and the theoretical risk of major morbidity or death is less than 1% (neither has yet occurred, to our knowledge). The most common complication is groin hematoma.

ACTH Syndrome, Ectopic↗

The limited ability of inferior petrosal sinus sampling with corticotropin-releasing hormone to distinguish Cushing's disease from pseudo-Cushing states or normal physiology.

To determine whether petrosal sinus sampling is useful to distinguish patients with mild or intermittent Cushing's disease from normal subjects and individuals with pseudo-Cushing states, we performed bilateral inferior petrosal sinus sampling for ACTH before and after the administration of CRH in 7 eucortisolemic volunteers, 8 hypercortisolemic patients with pseudo-Cushing states, and 40 patients with ACTH-dependent Cushing's disease whose urinary free cortisol excretion was within the range found in patients with, pseudo-Cushing states (< 1000 nmol/day; < 360 micrograms/day). The ACTH level, the ratio of the inferior petrosal sinus ACTH to the peripheral venous ACTH concentration (the IPS:P ratio), and the greater ratio of right to left or left to right petrosal sinuses (the R:L ratio) were compared in patients with and without Cushing's disease. Maximal petrosal ACTH values were significantly elevated in patients with Cushing's disease compared to patients with pseudo-Cushing states before CRH administration (P < 0.001), but not after CRH. Maximal petrosal plasma ACTH values after the administration of CRH as high as 808 pmol/L (3670 pg/mL) and 469 pmol/L (2130 pg/mL) were found in patients with pseudo-Cushing states and in normal volunteers, respectively, whereas maximal petrosal ACTH levels as low as 10 pmol/L (46 pg/mL) were observed in patients with surgically proven Cushing's disease. Maximal and minimal IPS:P ratios were significantly greater in patients with Cushing's disease than in subjects without Cushing's disease before, but not after, CRH treatment. R:L ratios did not differ among groups either before or after CRH. All of the subjects without Cushing's disease showed large R:L gradients, consistent with the notion of one dominant petrosal sinus containing a greater percentage of pituitary effluent. The ACTH concentrations, IPS:P ratios, and R:L ratios exhibited great overlap between those with and without Cushing's disease, which resulted in a diagnostic accuracy of 81% at best for the diagnosis of Cushing's disease. We conclude that petrosal sinus sampling is of limited usefulness in distinguishing either normal individuals or patients with pseudo-Cushing states from those with mild Cushing's disease. This limited usefulness must be recognized when interpreting the results of petrosal sinus sampling in patients with mild or intermittent hypercortisolism who may have a pseudo-Cushing state. Because of these limitations, petrosal sinus sampling should be reserved for patients with clear clinical and biochemical evidence of Cushing's syndrome.

Adrenocortical Hyperfunction↗

Multiple pituitary hormone gradients from inferior petrosal sinus sampling in Cushing's disease.

Pre-operative bilateral simultaneous inferior petrosal sinus sampling with assessment of ACTH levels in the left and right sinuses and the periphery was performed in 9 patients with pituitary dependent Cushing's disease who were subsequently found at surgery to have basophil microadenomata. The novel observation of this study was the pattern of secretion of other pituitary hormones so that significant inter-sinus gradients greater than or equal to 1.4:1 were seen for beta-endorphin (2.8 +/- 1.3, mean +/- SEM), PRL (4.2 +/- 1.3) and GH (6.9 +/- 2.4) as well as for ACTH (5.1 +/- 1.1). There was no inter-sinus gradient for LH, FSH and TSH. In these 9 patients with adenomata, the correlations between the inter-sinus gradients for ACTH and beta-endorphin were r = 0.95 (P less than 0.01), ACTH and PRL r = 0.90 (P less than 0.01) and for ACTH and GH r = 0.89 (P less than 0.05). This close association between the gradients for ACTH and other anterior pituitary hormones could be due either to co-secretion of beta-endorphin, PRL and GH by the ACTH-producing pituitary adenomata or to a paracrine effect of beta-endorphin from the tumours on adjacent pituitary tissue. By reflecting the central pituitary hormone milieu, petrosal sinus sampling can give information about pituitary function unobtainable from peripheral hormone levels.

Adolescent↗