Expert Consensus on Bilateral Inferior Petrosal Sinus Sampling in the Diagnosis of Cushing′s Syndrome (2023) / 罕见病研究

@#Cushing′s syndrome(CS)is a clinical syndrome caused by a variety of causes, with main manifestations exhibited by central obesity, purple skin striae, hypertension, and diabetes. In patients with adrenocorticotropic hormone(ACTH)-dependent CS, the result of bilateral inferior petrosal sinus sampling(BIPSS)is the gold standard for determining the source of ACTH in the absence of routine imaging findings.However, the indications, contraindications, operating procedures, precautions and outcome judgments of BIPSS differ from one medical center to another, and there are currently no international and domestic clinical guidelines and expert consensus on BIPSS. In order to further improve the operation specifications of BIPSS in the diagnosis process of difficult CS, the Hypothalamic and Pituitary Disease Group of the China Alliance for Rare Diseases and the Innovation Center of Pituitary Diseases of Peking Union Medical College Hospital organized experts in endocrinology, interventional radiology, neurosurgery and laboratory in China to formulate this consensus. This consensus aims to provide standardized methodological guidance for the use of BIPSS in the differential diagnostic process of CS in clinical practice.

Approach to the patient with Cushing′s disease with a false negative result in inferior petrosal sinus sampling / 中华内分泌代谢杂志

Bilateral inferior petrosal sinus sampling(BIPSS), with or without desmopressin stimulation, is the gold standard in the diagnosis of Cushing′s disease. A few of patients with Cushing′s disease present a false negative result in BIPSS. These patients are often misdiagnosed as ectopic adrenocorticotropin(ACTH) syndrome(EAS). Here we report a case of Cushing′s disease with a false negative BIPSS, in the hope to aid clinical physicians in the differential diagnosis and treatment of ACTH-dependent Cushing′s syndrome.

ACTH Dependent Cushing’s Syndrome: A 72-Hour Trial of Octreotide will Identify Patients with Pituitary Dependent and Ectopic ACTH Overproduction

Aims:To determine whether the use of an octreotide suppression test will reliably distinguish pituitary from ectopic ACTH overproduction. Somatostatin receptors are expressed in NETs, but are downgraded in the pituitary as the result of hypercortisolaemia. Octreotide should therefore lower ACTH and cortisol levels in patients with NETs but not in patients with Cushing’s disease and pituitary tumors. Methodology:A cross sectional study was performed in 13 patents with ACTH dependent Cushing’s (8 women, 5 men) with ages ranging between 21 to 40 years were studied. Serum cortisol concentrations were measured at 0800 hrs before and during the administration of. Octreotide at a dosage of 100 mcg subcutaneously every 8 hours for 72 hours.Results:The serum cortisol concentrations returned to normal in 4 patients who were later documented to have ectopic disease, two with typical bronchial carcinoids and two with pancreatic NETs and metastatic disease. The other 9 patients had no suppression in serum cortisol concentrations and were documented later to have pituitary tumours.Conclusion:These results indicate that a short trial of octreotide will identify patients with ectopic disease as evidenced by a fall inserum cortisol levels whereas in those with Cushing’s disease and pituitary tumours serum cortisol levels remains unchanged. Recommendation: We recommend all patients with ACTH dependent Cushing’s syndrome have an octreotidesuppression test, even if the MRI shows an adenoma, so as to exclude the possibility of a pituitary incidentaloma in a patient with ectopic disease, or false localization from IPSS to the pituitary gland due to ectopic CRH secretion

Treatment of primary orbital varix via inferior petrosal sinus approach / 中国脑血管病杂志

Objective To investigate the effectiveness of treatment of primary orbital varix via venous embolization therapy approach. Methods From January 2007 to January 2015,the clinical data of 12 patients with primary orbital varix were analyzed retrospectively. All the micro-catheters were implanted via the inferior petrosal sinus approach. The microcoils and Onyx18 were used to embolize the primary orbital varix. Four patients were embolized with micro-coils only, three were embolized with Onyx, and five were embolized with microcoil + Onyx. Results After successful catheterization, the lesions were totally embolized in 12 patients. The symptoms of postural exophthalmos disappeared and the pain was relieved,the depressed symptom of eyeball disappeared in 10 cases, and two patients were relieved partially ( single material embolization) . Nine patients were followed up for 6 to 24 months. The orbital DSA,MRI or CT re-examination was performed. The thrombosis of orbital varices within the lesions was observed and no cavity was found. One of the patients suffered from limited lateral eyeball abduction. Another three were lost to follow up. Conclusion The embolization treatment of primary orbital varix is safe, effective, and convenient via inferior petrosal sinus approach.

Treatment of primary orbital varix via inferior petrosal sinus approach / 中国脑血管病杂志

Objective To investigate the effectiveness of treatment of primary orbital varix via venous embolization therapy approach. Methods From January 2007 to January 2015,the clinical data of 12 patients with primary orbital varix were analyzed retrospectively. All the micro-catheters were implanted via the inferior petrosal sinus approach. The microcoils and Onyx18 were used to embolize the primary orbital varix. Four patients were embolized with micro-coils only, three were embolized with Onyx, and five were embolized with microcoil + Onyx. Results After successful catheterization, the lesions were totally embolized in 12 patients. The symptoms of postural exophthalmos disappeared and the pain was relieved,the depressed symptom of eyeball disappeared in 10 cases, and two patients were relieved partially ( single material embolization) . Nine patients were followed up for 6 to 24 months. The orbital DSA,MRI or CT re-examination was performed. The thrombosis of orbital varices within the lesions was observed and no cavity was found. One of the patients suffered from limited lateral eyeball abduction. Another three were lost to follow up. Conclusion The embolization treatment of primary orbital varix is safe, effective, and convenient via inferior petrosal sinus approach.

A patient with Cushing disease lateralizing a pituitary adenoma by inferior petrosal sinus sampling using desmopressin: a case report

A 14-year-old girl was referred for evaluation of the etiology of Cushing syndrome. During the previous 2 years, she had experienced weight gain, secondary amenorrhea, growth retardation, and back pain. Random serum cortisol level, 24-hour urinary free cortisol excretion, and overnight and low-dose dexamethasone suppression tests suggested Cushing syndrome. Midnight adrenocorticotropic hormone (ACTH) level and high-dose dexamethasone suppression test confirmed Cushing disease. Pituitary magnetic resonance imaging was suspicious for microadenoma. To eliminate ectopic ACTH syndrome, and lateralize the pituitary tumor, inferior petrosal sinus sampling (IPSS) was performed by desmopressin use to stimulate ACTH. Finally, the patient was diagnosed with Cushing disease due to ACTH-secreting pituitary microadenoma, lateralized to the left side; subsequently underwent transsphenoidal surgery. Here we report a case of a 14-year-old girl diagnosed with Cushing disease with a pituitary tumor lateralized by IPSS using desmopressin, which is very rare in pediatric Cushing disease.

Transvenous Coil Embolization for Dural Arteriovenous Fistulas of the Ophthalmic Sheath: Report of Two Cases and Review of the Literature

We present two patients with a dural arteriovenous fistula (dAVF) of the ophthalmic sheath who developed progressive exophthalmos, conjunctival chemosis, and visual loss. These symptoms mimic those of cavernous sinus dAVFs. Dural AVFs of the ophthalmic sheath are extremely rare and their clinical management is controversial. We successfully treated these two patients by transvenous coil embolization. Transvenous embolization appears to be a safe and effective method to treat dAVFs of the ophthalmic sheath.

Clinical Guidelines for the Diagnosis and Treatment of Cushing's Disease in Korea

Cushing's disease (CD) is a rare disorder characterized by the overproduction of adrenocorticotropic hormone due to a pituitary adenoma that ultimately stimulates excessive cortisol secretion from the adrenal glands. Prior to the detection of pituitary adenomas, various clinical signs of CD such as central obesity, moon face, hirsutism, and facial plethora are usually already present. Uncontrolled hypercortisolism is associated with metabolic, cardiovascular, and psychological disorders that result in increased mortality. Hence, the early detection and treatment of CD are not only important but mandatory. Because its clinical manifestations vary from patient to patient and are common in other obesity-related conditions, the precise diagnosis of CD can be problematic. Thus, the present set of guidelines was compiled by Korean experts in this field to assist clinicians with the screening, diagnoses, and treatment of patients with CD using currently available tests and treatment modalities.

MORPHOLOGICAL AND MORPHOMETRIC STUDY OF JUGULAR FORAMEN IN SOUTH INDIAN POPULATION.

Background: The jugular foramen, the bony opening on the base of skull, is an opening through which pass the ninth, tenth, and eleventh cranial nerves, two dural sinuses, and the meningeal branches of the occipital and ascending pharyngeal arteries. The increasing use of modern diagnostic procedures and new surgical approaches has created a need for much more detailed anatomical studies and explanations. This article reveals some additional features. Material and Methods: 324 jugular foramina of skulls of persons of unknown age and gender were examined. The morphological characteristics of all the investigated jugular foramina were described, measured, and compared, taking into consideration their side. Results: Jugular foramina were studied for a review of its morphology, morphometry and its comparison with previous studies. Different shapes and sizes of jugular foramen were seen. Laterality was also noticed, compartmentation was also observed which was found to be statistically significant. Conclusions: A detailed examination of the jugular foramen anatomy was performed. The main types of jugular foramina and the frequencies of bipartite or tripartite division were established. Several dimensions of the parts of the jugular foramen were measured. Some new data could provide important information about the anatomy of the jugular foramen for reliable surgical interventions in this area.

Abducens Nerve Palsy Complicated by Inferior Petrosal Sinus Septic Thrombosis Due to Mastoiditis

We present a very rare case of a 29-month-old boy with acute onset right abducens nerve palsy complicated by inferior petrosal sinus septic thrombosis due to mastoiditis without petrous apicitis. Four months after mastoidectomy, the patient fully recovered from an esotropia of 30 prism diopters and an abduction limitation (-4) in his right eye.

The value of bilateral inferior petrosal sinus sampling in the differential diagnosis of ACTH-dependent Cushing's syndrome / 中华内分泌代谢杂志

Objective To evaluate the values of bilateral inferior petrosal sinus sampling ( BIPSS),high dosage dexamethasone suppression test (HDDST) and pituitary image in the differential diagnosis of ACTH-dependent Cushing's syndrome. Methods Totally 87 patients with confirmed pathological diagnosis were recruited in the study.All received the procedure of BLPSS,HDDST,and pituitary MRI with dynamic enhancement.The diagnostic performances of three differential diagnosis methods in ACTH-dependent Cushing's syndrome were evaluated.Results Seventy-eight patients were diagnosed as cases of pituitary ACTH adenoma,and the remaining 9 were confirmed cases of ectopic ACTH syndrome due to the thymic carcinoid.The sensitivity and specificity of HDDST,pituitary MRI,and BIPSS for the diagnosis of ACTH-dependent Cushing's syndrome were 82.1％ and 100％,79.5％ and 44.4％,92.3％ and 100％,respectively.In Cushing's disease,the diagnostic accuracy was 83.9％ with HDDST,77.0％with pituitary MRI,and93.1％ with BIPSS.In those patients with Cushing's disease,the coincidence of lateralization was 83.9％ with BIPSS and 64.5％ with MRII.Conclusion BIPSS was better than the other two methods in differential diagnosis of ACTH-dependent Cushing's syndrome.Compared with the pituitary MRI,the concordant rate of BIPSS in lateralization of the tumor is higher,and it is more reliable.

Evaluation of desmopressin stimulated bilateral inferior petrosal sinus sampling in diagnosing Cushing′s disease / 中华内分泌代谢杂志

Objective To evaluate desmopressin stimulated inferior petrosal sinus sampling in diagnosing Cushing′s disease.Methods Sixteen ACTH-dependent Cushing′s disease patients underwent bilateral desmopressin stimulated inferior petrosal sinus ( IPS ) sampling because of negative or equivocal magnetic resonance imaging.Cortisol response to high-dose dexamethasone suppression test was also evaluated.ACTH sampling was taken from a peripheral vein and bilateral IPS before and both 5 and 10 min after injection of desmopressin.Diagnosis was based on the ratio of ACTH level in between IPS to peripheral vein by desmopressin test.Diagnosis was confirmed after surgery.Results High-dose dexamethasone suppression test showed suppressible in 9 of 16 patients with Cushing′s disease.An IPS gradient ＞2 was found in 14 of the 16 cases (87.5％ )with Cushing′s disease after desmopressin injection,while before injection the respective figure was 12 of 16 (75.0％).No severe adverse effects were observed during or after the procedure.Conclusion Desmopressin test during bilateral IPS sampling is a safe and effective diagnostic procedure in Cushing′s disease.

Bilateral Inferior Petrosal Sinus Sampling by Unilateral Femoral Venous Approach / 신경중재치료의학

PURPOSE: Bilateral inferior petrosal sinus sampling (IPSS) is a direct method of distinguishing between pituitary and ectopic ACTH secretion. We present unilateral femoral route technique avoiding bilateral femoral venous puncture using two 4F catheters into both sides of IPSS in these obese patients. MATERIALS AND METHODS: Unilateral femoral puncture using 9F guiding catheter allowed two 4F catheters which can be introduced in each side of inferior petrosal sinus. To reduce bleeding in the gap between 2 catheters at the diaphragm of the 9F femoral sheath, we introduced a short guidewire provided along with femoral sheath. After removing the 9F sheath after procedure, we applied manual compression as usual. We evaluated any technical difficulty and other complications including the presence of hematoma at the puncture site 1 day and 30 days later. RESULTS: Bilateral IPSS by using two 4F catheters in both inferior petrosal sinuses was possible via unilateral femoral route via 9F sheath. There was no technical difficulty introducing 4F catheters into each IPS of both sides. After removing 9F femoral sheath, there was no other complication and no hematoma at the puncture site at 1 day and 30 days later. CONCLUSION: Unilateral femoral venous approach with a 9-French sheath can be used in IPSS. This technique allowed to pass two 4F catheters for IPSS at both sides and could avoid unnecessary bilateral femoral puncture in these obese patients without any hematoma formation after the procedure.

Diagnosis and treatment of pediatric and hebetic adrenocorticotropic hormone secreting pituitary microadenoma / 上海交通大学学报（医学版）

Objective To investigate the methods of diagnosis and treatment of pediatric and hebetic adrenocorticotropic hormone ( ACTH) secreting pituitary microadenoma. Methods The data of 10 patients with ACTH secreting pituitary microadenoma were retrospectively analysed. ACTH secreting pituitary microadenoma was diagnosed by clinical manifestations, biochemical and imaging findings, and 5 patients underwent bilateral inferior petrosal sinus sampling ( BIPSS). Transsphenoidal surgery was performed on all the patients under microscope, and the tumor specimens were detected by immunohistochemistry. Results Immunohistochemical examination revealed that ACTH was positive in 8 cases and negative in 2 cases. Patients were followed up for 12 to 63 months, 7 cases (70%) were cured, one (10%) achieved remission, and the other two (20%) experienced recurrence. Conclusion BIPSS is helpful in the diagnosis and localization of pediatric and hebetic ACTH pituitary microadenoma, and transsphenoidal surgery is the optimal choice of treatment.

A TSH-secreting pituitary microadenoma diagnosed with inferior petrosal sinus sampling: Case report / 대한내과학회지

Thyroid stimulating hormone (TSH)-secreting pituitary adenomas are rare tumors of the pituitary gland and represent 1~2% of all pituitary adenomas. A TSH-secreting pituitary adenoma shows as a normal or elevated thyrotropin level in a hyperthyroid patient. We present a 32-year-old woman who was diagnosed with a TSH-secreting pituitary microadenoma. She had a high free T4, with a normal TSH and alpha-subunit. Bilateral inferior petrosal sinus sampling (IPSS) was done to confirm the alpha-subunit secreting adenoma, and the concentration of the alpha-subunit was high on the tumor side. The pituitary microadenoma was removed, and her TSH and free T4 levels decreased to normal. IPSS may help give an accurate diagnosis in the patient with a normal alpha-subunit.

Pitfalls in the diagnosis of Cushing's syndrome: [review]

Among endocrine disorders, Cushing's syndrome (CS) is certainly one of the most challenging to endocrinologists due to the difficulties that often appear during investigation. The diagnosis of CS involves two steps: confirmation of hypercortisolism and determination of its etiology. Biochemical confirmation of the hypercortisolaemic state must be established before any attempt at differential diagnosis. Failure to do so will result in misdiagnosis, inappropriate treatment, and poor management. It should also be kept in mind that hypercortisolism may occur in some patients with depression, alcoholism, anorexia nervosa, generalized resistance to glucocorticoids, and in late pregnancy. Moreover, exogenous or iatrogenic hypercortisolism should always be excluded. The three most useful tests to confirm hypercortisolism are the measurement of 24-h urinary free cortisol levels, low-dose dexamethasone-suppression tests, and determination of midnight serum cortisol or late-night salivary cortisol. However, none of these tests is perfect, each one has different sensitivities and specificities, and several are usually needed to provide a better diagnostic accuracy. The greatest challenge in the investigation of CS involves the differentiation between Cushing's disease and ectopic ACTH syndrome. This task requires the measurement of plasma ACTH levels, non-invasive dynamic tests (high-dose dexamethasone suppression test and stimulation tests with CRH or desmopressin), and imaging studies. None of these tests had 100 percent specificity and their use in combination is usually necessary. Bilateral inferior petrosal sinus sampling is mainly indicated when non-invasive tests do not allow a diagnostic definition. In the present paper, the most important pitfalls in the investigation of CS are reviewed.

Entre as doenças endócrinas, a síndrome de Cushing (SC) é certamente uma das mais desafiadoras para o endocrinologista, devido às dificuldades que comumente surgem durante a investigação. O diagnóstico de SC envolve dois passos: a confirmação do hipercortisolismo e a determinação de sua etiologia. A confirmação bioquímica do excesso de cortisol precisa ser estabelecida antes de qualquer tentativa de diagnóstico diferencial; caso contrário, poderá resultar em diagnóstico incorreto, tratamento impróprio e manejo insuficiente. Deve também ser lembrado que hipercortisolismo pode ocorrer em certos pacientes com depressão, alcoolismo, anorexia nervosa, resistência generalizada aos glicocorticóides e no final da gravidez. Além disso, hipercortisolismo exógeno ou iatrogênico deverá ser sempre excluído. Os três testes mais úteis para a confirmação do hipercortisolismo são: a medida do cortisol livre em urina de 24 h, os testes de supressão com dexametasona (TSD) em doses baixas e a determinação do cortisol sérico à meia-noite ou do cortisol salivar no final da noite. Contudo, nenhum deles é perfeito, cada um com sua sensibilidade e especificidade, sendo vários deles usualmente necessários para fornecer uma melhor acurácia diagnóstica. O maior desafio na investigação da SC envolve a diferenciação entre a doença de Cushing e a síndrome do ACTH ectópico. Esta tarefa requer a medida dos níveis plasmáticos de ACTH, testes dinâmicos não-invasivos (TSD com doses altas e testes de estímulo com CRH ou desmopressina) e estudos de imagem. Nenhum desses testes tem 100 por cento de especificidade e muitas vezes é necessário seu uso combinado. Amostragem venosa do seio petroso inferior está indicada principalmente quando os testes não-invasivos não permitem uma definição diagnóstica. Neste artigo, revisaremos as mais importantes armadilhas na investigação da SC.

The role of bilateral inferior petrosal sinus sampling in the diagnosis of Cushing's syndrome

Adrenocorticotropin hormone (ACTH)-dependent Cushing's syndrome is most often due to a pituitary corticotroph adenoma, with ectopic ACTH-secreting tumors representing approximately 15 percent of cases. Biochemical and radiological techniques have been established to help distinguish between these two entities, and thus aid in the localization of the neoplastic lesion for surgical resection. The test that offers the highest sensitivity and specificity is bilateral inferior petrosal sinus sampling (BIPSS). BIPSS is an interventional radiology procedure in which ACTH levels obtained from venous drainage very near the pituitary gland are compared to peripheral blood levels before and after corticotropin hormone (CRH) stimulation. A gradient between these two locations indicates pituitary Cushing's, whereas the absence of a gradient suggests ectopic Cushing's. Accurate BIPSS results require hypercortisolemia to suppress normal corticotroph ACTH production and hypercortisolemia at the time of the BIPSS to assure excessive ACTH secretion. In some cases, intrapituitary gradients from side-to-side can be helpful to localize small corticotroph adenomas within the sella. BIPSS has rare complications and is considered safe when performed at centers with experience in this specialized technique.

A síndrome de Cushing (SC) ACTH-dependente é mais freqüentemente devida a um adenoma corticotrófico da hipófise, com os tumores ectópicos secretores de ACTH representando aproximadamente 15 por cento dos casos. Técnicas bioquímicas e radiológicas foram estabelecidas para permitir a distinção entre essas duas entidades e, assim, auxiliar na localização da lesão neoplásica para ressecção cirúrgica. O teste que oferece a mais alta sensibilidade e especificidade é a coleta bilateral de amostras de sangue do seio petroso inferior (BIPSS). BIPSS é um procedimento de intervenção radiológica no qual os níveis de ACTH obtidos da drenagem venosa bem próxima da hipófise são comparados com os níveis sanguíneos periféricos antes e após estímulo com corticorrelina (CRH). Um gradiente entre essas duas localizações indica SC hipofisário, enquanto a ausência de gradiente sugere SC ectópica. Resultados acurados na BIPSS requerem a presença de hipercortisolemia e que ela suprima normalmente a produção de ACTH pelo corticotrofos por ocasião da BIPSS para garantir a secreção excessiva de ACTH. Em alguns casos, os gradientes intra-hipofisários de um lado para outro podem ser úteis na localização de pequenos adenomas corticotróficos no interior da sela. A BIPSS raramente apresenta complicações, sendo considerada segura quando realizada em centros com experiência nessa técnica especializada.

A Case of Raymond-Cestan Syndrome Caused by Inferior Petrosal Sinus Sampling / 대한내분비학회지

Inferior petrosal sinus sampling (IPSS) plays an important role in the assessment of patients with ACTH-dependent Cushing's syndrome. IPSS has been described as an innocuous, essentially risk-free procedure. Neurological complications associated with IPSS are rare. Previously reported neurological complications include brain stem infraction, pontine hemorrhage and subarachnoid hemorrhage. A 26-year-old woman was admitted to the hospital because of a moon face and a buffalo hump. A MRI showed a suspicious, but uncertain, area on the left side of the sella turcica. IPSS was performed as an appropriate means of providing more information about the side of the ACTH source. Immediately after the procedure, the woman experienced double vision, caused by a complete sixth nerve palsy of the left eye, together with a contralateral hemiparesis. From a clinical point of view, abducens nerve palsy and contralateral hemiparesis corresponded to Raymond-Cestan syndrome. I report a case of Raymond-Cestan syndrome, following petrosal sinus sampling in a female patient with ACTH-dependent Cushing's syndrome. To the best of our knowledge, this complication associated with petrosal sinus sampling has only been described in one previous case report. Although IPSS may provide essential information in the investigation of Cushing's syndrome, the possibility of very occasional but devastating complications should be remembered.

Diagnosis of Cushing's Disease by Inferior Petrosal Sinus Sampling (IPSS): Evidence of False Negative Results / 대한내분비학회지

BACKGROUND: While inferior petrosal sinus sampling (IPSS) correctly diagnoses pituitary dependent Cushings syndrome if a significant ratio of plasma ACTH between the IPS and the peripheral blood is demonstrated, little has been said about the significance of a negative ratio in Cushings disease (e.g. false negative result). We evaluated the results of IPSS with Cushings disease, and compared them with imaging findings through transsphenoidal surgery. METHODS: 29 patients with Cushings disease underwent transsphenoidal examination of the pituitary gland from 1989 to 1998 at Seoul National University Hospital were evaluated. We compared the results of IPSS and imaging findings with sellar CT or dynamic MRI. The ratio of the ACTH concentrations at the IPS and in the peripheral blood (IPS:P ratio) and the ratio of the ACTH concentrations between the IPSs (interpetrosal ratio) were calculated before and after CRH infusion. RESULTS: With IPSS the diagnosis of Cushings disease was possible in 90% (26/29), and 3 cases in whom IPSS did not show significant IPS:P ACTH ratio were confirmed to be Cushings disease through hemihypophysectomy of lesion suspected by sellar dynamic MRI and achieved remission after operation (e.g. false negative result of diagnosis for Cushings disease by IPSS). However, accurate localization of microadenoma was achieved in only 59% (17/29). Imaging study detected microadenoma in 76% (22/29) and correctly localized in 66% (19/29). Both IPSS and imaging study precisely localized the pituitary microadenoma in 10 (34.5%) cases of 29 cases and a discrepancy between two studies existed in 7 (24.1%) cases in which the imaging study correctly localized microadenoma in 6 cases and IPSS in 1 case. CONCLUSION: Only when a significant IPS:P ACTH ratio is present can Cushings disease be established by IPSS. The absence of a significant IPS:P ACTH ratio does not necessarily imply ectopic secretion of ACfH, nor does it exclude Cushings disease. The results of lateralization by IPSS do not remove the need for transsphenoidal examination of the sella turcica because false negative result can be. IPSS and radiologic study should be complementary used in diagnosis of Cushings disease and localization of microadenoma, as IPSS can be used when sellar imaging study failed to visualize the lesion and hemihypophysectomy of suspected lesion by imaging study can be considered when IPSS did not show significant ratio of ACTH.

The Localization of Microadenoma with Sella Imaging Study and Inferior Petrosal Sinus Sampling in Cushing's Disease / 대한내분비학회지

Background: Inferior petrosal sinus sampling(IPSS) is known to be useful for the differential diagnosis of ACTH-dependent Cushings syndrome and for the preoperative lateralization of pituitary microadenoma. We tried to analyze the relative value of IPSS in localization of microadenoma as compared with sella imaging study including computerized tomogram(CT) or magnet resonance imaging(MRI) in Cushings disease. Methods: We reviewed the clinical records of 21 patients with Cushings disease who underwent IPSS and the radiologic study such as sella CT or sella MRI preoperatively followed by transsphenoidal microsurgery. By pathologic examination including immunohistochemistry and postoperative clinical and biochemical evaluation we confirmed the diagnosis of Cushings disease due to pituitary microadenoma in all 21 cases. Results: Sella CT or sella MRI detected microadenoma in 57.1% of cases( =12/21), while recently available dynamic MRI did so in 7 out of S cases. With IPSS the diagnosis of Cushings disease was possible in 90.5% of cases(= 19/21), but accurate lateralization of microadenoma was achieved in only 63.2% of cases( =12/19). IPSS precisely localized the pituitary microadenoma in 6 out of 9 cases whose lesion were not detected by the radiologic study. Of 7 cases in which IPSS failed to localize microadenoma, the radiologic study detected the lesion in 6 cases. Of 5 cases in which IPSS and the radiologic study showed a discrepancy in location of microadenoma, the radiologic study correctly localizaed the lesion in 4 cases and IPSS did so in one case. Conclusion: IPSS is not more reliable than sella imaging study for preoperative localization of microadenoma in Cushings disease. However it might have a complementary role, especially when sella imaging study failed to visualize the lesion.