Transsphenoidal Pituitary Adenomectomy Research Articles

Advances in Skull Base Reconstruction during Neuroendoscopic Transsphenoidal Pituitary Adenomectomy

Advances in Skull Base Reconstruction during Neuroendoscopic Transsphenoidal Pituitary Adenomectomy

Treatment outcomes of neuroendoscopic and microscopic trans-sphenoidal pituitary adenomectomies and the effects on hormone levels.

We aimed to compare the treatment outcomes of neuroendoscopic and microscopic trans-sphenoidal pituitary adenomectomies, as well as the effects on hormone levels and clinical symptoms. A total of 82 patients with pituitary adenomas that were surgically resected from June 2018 to March 2021 were selected and divided into a group receiving neuroendoscopic trans-sphenoidal pituitary adenomectomy (group A, N.=40), and the other group receiving microscopic surgery (group B, N.=42). Surgery-related indices, hormone levels before discharge and alleviation of symptoms 24 weeks after surgery were compared. Both groups had significantly different degrees of tumor resection (P<0.05). The proportion of cases receiving total adenomectomy in group A significantly exceeded that of group B (P<0.05). The surgical time of group A was significantly longer than that of group B (P<0.05). Group A had significantly shorter mean hospitalization stay than that of group B (P<0.05). The postoperative hormone levels of both groups decreased significantly differently (P<0.05). Before discharge, the hormone recovery rate of group A significantly surpassed that of group B (P<0.05). The hormone levels of cases with prolactinoma, adrenocorticotropic hormone adenoma and growth hormone adenoma in group A dropped more significantly than those of group B did (P<0.05). Compared with microscopic surgery, neuroendoscopic trans-sphenoidal pituitary adenomectomy worked more effectively, induced fewer postoperative complications and better promoted the postoperative recovery of hormone levels.

Short-Term Complications of Microscopic Trans Nasal Transsphenoidal Pituitary Adenomectomy

Background/Objective: The commonest of pituitary gland tumors is pituitary adenoma which may be excised transcranially or trans nasal trans sphenoidal using either microscope or endoscope, in this study, the microscope was used. The objective was to see the short-term outcome of patients after microscopic transnasal trans-sphenoidal pituitary adenomectomy.&#x0D; Material &amp; Methods: This was a descriptive prospective study carried out from July 2019 to July 2021. 80 cases were included. All patients were investigated by contrast brain MRI, hormonal assay for pituitary gland &amp; visual perimetry. Patients were evaluated for complications at 48 hours and 7 days.&#x0D; Results: Mean age of the study population was 41.78 ± 11.75 years. There were 61 (76%) men &amp; 19 (24%) women. 55 (68.8%) patients had functioning and 25 (3.3%) patients had nonfunctioning adenoma. Among 33 (41.3%) patients size of the adenoma was &lt; 0.9 cm and 47 (58.8%) patients had adenoma &gt; 1.0 cm. 12 patients had CSF leaks within 48 hours of surgery and 5 had a persistent leak on the 7th day. No statistically significant association was seen between age, gender, and size of adenoma and persistent CSF leak (P &gt; 0.05). Diabetes insipidus was found in 9 patients. 3 had post-operative hematoma, 01 patient had meningitis and 2 patients died.&#x0D; Conclusion: microscopic transnasal trans-sphenoidal surgery is a safe procedure yet associated with significant complications.

Concurrent mutations of germline GPR101 and somatic USP8 in a pediatric giant pituitary ACTH adenoma: a case report

BackgroundCushing’s disease (CD) is rare in pediatric patients. It is characterized by elevated plasma adrenocorticotropic hormone (ACTH) from pituitary adenomas, with damage to multiple systems and development. In recent years, genetic studies have shed light on the etiology and several mutations have been identified in patients with CD.Case presentationA girl presented at the age of 10 years and 9 months with facial plethora, hirsutism and acne. Her vision and eye movements were impaired. A quick weight gain and slow growth were also observed. Physical examination revealed central obesity, moon face, buffalo hump, supra-clavicular fat pads and bruising. Her plasma ACTH level ranged between 118 and 151 pg/ml, and sella enhanced MRI showed a giant pituitary tumor of 51.8 × 29.3 × 14.0 mm. Transsphenoidal pituitary debulk adenomectomy was performed and immunohistochemical staining confirmed an ACTH-secreting adenoma. Genetic analysis identified a novel germline GPR101 (p.G169R) and a somatic USP8 (p. S719del) mutation. They were hypothesized to impact tumor growth and function, respectively.ConclusionsWe reported a rare case of pediatric giant pituitary ACTH adenoma and pointed out that unusual concurrent mutations might contribute to its early onset and large volume.

Характеристика клініко-інструментальних і гормональних показників у пацієнтів із АКТГ-залежним синдромом Кушинга до і після лікування

Ендогенний гіперкортицизм є наслідком надмірної секреції синтезованих корою наднирників гормонів. Мета дослідження: вивчити характеристику клінічних, біохімічних, гормональних та інструментальних показників у хворих з АКТГ-залежним синдромом Кушинга до лікування і через 6 місяців після нього. Матеріали та методи. Під спостереженням перебувало 60 хворих з АКТГ-залежним синдромом Кушинга. Результати. У доопераційному періоді в пацієнтів з АКТГ-залежним синдромом Кушинга виявлено значні відхилення як показників антропометрії (індекс маси тіла, окружність талії, окружність стегон), так і ліпідного спектра крові. У доопераційному періоді в пацієнтів з АКТГ-залежним синдромом Кушинга виявлено вірогідно низькі базальні рівні лютеїнізуючого, фолікулостимулюючого, соматотропного гормона на тлі гіперкортизолемії та гіперінсулінемії. Висновки. Через 6 місяців після трансназальної селективної аденомектомії гіпофіза спостерігалися вірогідно низькі значення середніх величин лютеїнізуючого, фолікулостимулюючого, соматотропного, адренокортикотропного гормона на тлі нормальних показників кортизолу та імунореактивного інсуліну, що вказує на післяопераційний гіпопітуїтаризм. У післяопераційному періоді пацієнти з АКТГ-залежним синдромом Кушинга потребують замісної гормональної терапії.

SAT-250 A Case of Late Recurrent Cushing’s Disease Presenting with Proximal Myopathy

Patients with Cushing’s disease (CD) present with a variety of symptoms and comorbidities including central obesity, hypertension, hyperglycemia, fatigue, weakness, insomnia and mood changes. Proximal myopathy is one of the classical signs of hypercortisolism and patients typically report difficulty rising from a seated position or climbing stairs. Due to variability in clinical presentation, with some patients showing subtle or few symptoms, the diagnosis of CD can be delayed. We describe a patient with late recurrent CD whose primary symptom was proximal myopathy. A 63 yr. old man presented to our clinic with complaints of progressive muscle weakness and fatigue. He had been successfully treated for CD at age 35 with transsphenoidal pituitary adenomectomy. He had been on hormonal replacement therapy for panhypopituitarism since surgery including levothyroxine, testosterone and glucocorticoids. He noted progressive weakness for several years prior to presentation in our clinic. Earlier evaluations revealed vitamin B12 and vitamin D deficiency, but supplementation did not lead to significant symptom improvement. He suffered two episodes of unprovoked deep venous thrombosis with pulmonary embolism and developed a left biceps tear that required hospital admission. During admission, his muscle weakness was exacerbated by immobility and he was subsequently referred to endocrinology for consideration of steroid induced myopathy. He had been on physiologic glucocorticoid replacement since diagnosed with panhypopituitarism. At the time of our evaluation, he was able to ambulate with a walker, but was unable to climb stairs, drive a car and required assistance with activities of daily living. His only other symptoms were fatigue and insomnia. Laboratory testing after holding prednisone revealed: morning cortisol 31.7 mcg/dl (reference interval [RI], 4.0-22.0), ACTH 128 pg/mL (RI 6 - 50), FSH <0.7 mIU/mL (RI 1.6 - 8.0), LH <0.2 mIU/mL (RI 1.6 - 15.2), testosterone 85 ng/dL (RI 250 - 827), IGF-1 55 ng/mL (RI 41 - 279), prolactin 4.9 ng/mL (RI 2.0 - 18.0), TSH 0.01 mIU/L (RI 0.40 - 4.50), free T4 1.5 ng/dL (RI 0.8 - 1.8), HbA1c 6.8% (RI <5.7%). Prednisone was discontinued and hypercortisolism was confirmed by 1 mg overnight dexamethasone (dex) suppression test (Cortisol 32.4 mcg/dL, dex 517 ng/dL, RI 180-550 ng/dL) and elevated 24 h urine free cortisol 315.4 mcg/24h (RI 4.0 - 50.0). 8 mg DST showed mild cortisol suppression (Cortisol 21.2 mcg/dL, dex >1000 ng/dl). MRI confirmed recurrent tumor (1.2 x 0.8 x 1.3 cm) extending into the right cavernous sinus and the patient underwent repeat transsphenoidal tumor resection. Pathology confirmed ACTH adenoma. Our case report highlights that patients with CD can have late recurrences and require long term monitoring for return of hypercortisolism, even in cases of prior panhypopituitarism.

Risk factors related to intracranial infections after transsphenoidal pituitary adenomectomy under endoscope.

Background - Up to now, the risk factors related to intracranial infections after transsphenoidal pituitary adenomectomy remain controversial. Purpose - To analyze the risk factors related to intracranial infections after transsphenoidal pituitary adenomectomy under an endoscope, and to provide evidence for preventing and controlling the occurrence and development of infections. A total of 370 patients receiving endoscopic transsphenoidal pituitary adenomectomy in our hospital from January 2014 to October 2017 were selected. The risk factors related to postoperative intracranial infections were analyzed. The hospitalization lengths and expenditures of patients with and without intracranial infections were compared. Of the 370 patients, 18 underwent postoperative intracranial infections, with the infection rate of 4.86%. Intraoperative blood loss >120 mL, cerebrospinal leakage, diabetes, preoperative use of hormones, macroadenoma as well as surgical time >4 h all significantly increased the infection rate (P<0.05). Preoperative use of antibacterial agents prevented intracranial infection. Compared with patients without intracranial infections, the infected ones had significantly prolonged hospitalization length and increased expenditure (P<0.05). Discussion - It is of great clinical significance to analyze the risk factors related to intracranial infection after endoscopic transsphenoidal pituitary adenomectomy, aiming to prevent and to control the onset and progression of infection. Intracranial infections after endoscopic transsphenoidal pituitary adenomectomy were affected by many risk factors, also influencing the prognosis of patients and the economic burden.

Difference in the incidence of cerebrospinal fluid leakage and residual tumors between functional and nonfunctional pituitary adenomas treated by endoscopic transsphenoidal pituitary adenomectomy.

ObjectiveThis study compared the incidence of cerebrospinal fluid (CSF) leakage and residual tumors between functional and nonfunctional pituitary adenomas treated with the endoscopic endonasal transsphenoidal approach (EETA).MethodsAll patients underwent endocrine examinations and brain magnetic resonance imaging before and after surgery. The length of admission, incidence of central diabetes insipidus, incidence of CSF leakage, symptom relief, and presence of residual tumors were compared between patients with functional and nonfunctional pituitary adenomas.ResultsThirty-eight patients were enrolled, among whom 12 and 26 had functional and nonfunctional pituitary adenomas, respectively. The incidence of CSF leakage was significantly higher in patients with nonfunctional adenomas; a hard or elastic tumor character accounted for the difference. A large tumor size and cavernous sinus invasion were risk factors for residual tumors. No significant differences were found in sex, length of admission, operative times, incidence of diabetes insipidus, or number of residual tumors between the two groups. The hormone levels were lower postoperatively than preoperatively in patients with nonfunctional adenomas.ConclusionNonfunctional pituitary macroadenomas resulted in more CSF leakage. Use of the rescue nasoseptal flap reduced unnecessary nasal destruction. Cooperation between a neurosurgeon and otolaryngologist was safer and more effective when using the EETA.

Comparison of Constructive Interference in Steady-State and T1-Weighted MRI Sequence at Detecting Pituitary Adenomas in Cushing's Disease Patients.

Background T1-weighted magnetic resonance imaging (MRI) remains the standard pituitary imaging sequence. However, up to 50% of pituitary adenomas are missed with standard imaging in Cushing's disease (CD) patients. Utility of other imaging sequences needs be explored. Objective To compare a T2-gradient echo sequence, constructive interference in steady state (CISS), with a contrast-enhanced (CE) T1-weighted sequence, volume-interpolated breath-hold examination (VIBE), in the detection of pituitary adenomas in CD patients. Design Retrospective analysis of CD patients who underwent endoscopic transsphenoidal pituitary adenomectomy at our institution. Patients and Measurement Twelve patients were included in the study. Two neuroradiologists, who were blinded to the patients' clinical and surgical findings, independently reviewed the CE-VIBE and CISS images. Localization of pituitary adenoma from imaging was compared with intraoperative localization. Results The averaged sensitivity of detecting pituitary adenoma in CD patients was not significantly different between CE-VIBE sequence (63%) and CISS sequence (54%). The positive predictive value was 75% (Observer A) and 100% (Observer B) with CE-VIBE sequence, and 64% (Observer A) and 100% (Observer B) with CISS sequence. In two patients, pituitary adenoma was easily localized with CISS sequence but hard to detect with CE-VIBE sequence. In two other patients, the adenoma was much better delineated on CE-VIBE sequence. Conclusion In our series, the addition of CISS sequence to T1-weighted MRI imaging protocols improved the detection of pituitary adenomas in CD patients. CISS sequence may be a useful adjunct to T1-weighted pituitary MRI protocols and an appropriate alternative for patients with gadolinium contraindications.

Clinical analysis of the related high risk factors of hyponatremia after transsphenoidal approach for pituitary adenomectomy andclinical nursing

Objective To explore the related high risk factors of hyponatremia after transsphenoidal approach for pituitary adenomectomy and to direct postoperative nursing. Methods The clinical data of seventy-seven patients suffering from pituitary adenomas with the way of treatment by transsphenoidal pituitary adenomectomy from June 2014 to May 2015 were summarized retrospectively. According to the value of postoperative serum natremia, the data were divided into hyponatremia group and non-hyponatremia group. The different data between the 2 groups were compared and the high risk factors related to hyponatremia were analyzed. Results Univariate analysis showed that gender(P= 0.254)and high blood pressure(P=0.742)were unrelated to postoperative hyponatremia and there was significant difference between two groups in age(P=0.038), max-diameter of tumors(P=0.004), preoperative pituitary dysfunction(P=0.013), visual deficit(P=0.000), operative procedure duration(P= 0.008)and diabetes mellitus rate(P=0.023). While Logistic regression analysis showed that preoperative visual deficit(OR=0.152, P=0.004, 95%CI 0.043-0.542)and preoperative pituitary dysfunction(OR=0.069, P=0.046, 95% CI 0.005-0.950)were independent factors for postoperative hyponatremia. Conclusions Hyponatremia is a common complication after transsphenoidal pituitary adenomectomy. The optimal treatment can benefit the early recovery and more careful nursing should be focused on these patients who are in high risk of postoperative hyponatremia. Key words: Pituitary adenomas; Hyponatremia; Nursing care; Post-operation

One case of a thyrotropin-secreting microadenoma and resistance to thyroid hormone with P453T mutation in TRβ gene

We investigated a 12-year-old girl with elevated serum FT3, FT4, and TSH levels. The sequence of thyroid hormone receptor β(TRβ)exons revealed a CCT→ACT transition mutation at nucleotide 453 site within exon 10, which resulted in the substitution of cytosine to adenosinein(P453T). Pituitary magnetic resonance image showed a pituitary micoradenoma. The patient underwent transsphenoidal pituitary adenomectomy. Pathological results exhibited positive TSH-β, GH, prolactin, ACTH, and α-HCG staining for the tumor. This is the first case report with thyroid hormone resistance syndrome and thyrotropin-secreting adenoma. Key words: Thyroid hormone resistance; Thyroid hormone receptor β; Gene mutation; Thyrotropin-secreting pituitary adenoma

Evaluation and Management of Thyrotropin-Secreting Pituitary Adenomas

Thyrotropin (TSH)-secreting pituitary adenomas are uncommon pituitary neoplasms. They have been increasingly recognized with the advent of ultrasensitive TSH assays and advanced pituitary imaging. Clinically, patients may often present with signs and symptoms of hyperthyroidism. Some patients may present with tumor-related local mass effect, anterior hypopituitarism or syndromes related to co-secretion of other pituitary hormones. Their diagnosis and differential diagnosis from other causes of hyperthyroidism and ‘inappropriate TSH secretion’ often presents a clinical challenge. While trans-sphenoidal pituitary adenomectomy remains the therapeutic modality of choice, medical treatment with somatostatin receptor agonists or dopamine agonists is often needed as adjunctive therapy or perhaps as a potential alternative to surgery. Radiation therapy to the sella may be advised as a third-line therapy.

Cortisol Levels as Predictors of Short- and Long-Term Adrenal Function After Endonasal Transsphenoidal Surgery for Pituitary Adenomas and Rathke's Cleft Cyst

Corticotropin (adrenocorticotropic hormone [ACTH]) deficiency due to transsphenoidal pituitary adenomectomy or Rathke’s cleft cysts extirpation is fairly low, mainly due to its monoclonal prevalence expression. It represents 20% of the cases, contrasting with other hypophyseal hormones, such as, antidiuretic hormone (arginine vasopressin), thyrotropin (thyroid-stimulating hormone), gonadotropins (follicle-stimulating hormone or luteinizing hormone) and growth hormone (GH) that may reach up to 40% to 50%. When low ACTH is found, it is generally permanent and close monitoring is vital. Statistics vary widely depending on tumor size and location, including the surgeon’s experience and/or compromise achieved by the medical team involved in this kind of process as well. Cortisol is of most importance, because a drop of circulating levels in the first 24 hours may be life-threatening, if replacement is not ensured with opportunity. Difficulties usually arise while attempting to establish the diagnosis and in delineating prognosis of hypocortisolism, which commonly relies on the accuracy of cortisol and corticotropin (ACTH) quantitative methods and/or qualitative clinical assessment. Preservation of ACTH/cortisol secretion when a tumor blockades the infundibulum or by surgical extension is not totally understood, albeit fragments of pituitary functional tissue have been found in neighboring zones like the ethmoid sinus or nasopharynx. A single morning or random serum cortisol quantitation in many cases do not necessarily correlate with impairment in cortisol secretion by the adrenal while attempting to evaluate intactness of the hypothalamic-pituitary-adrenal axis after a pituitary tumor removal. Nonetheless, the finding of a random serum cortisol 20 g/dL can rule out the possibility of adrenal insufficiency, whereas a concentration of cortisol 20 g/dL makes imperative a thorough investigation of adrenal deficit. Blood pressure monitoring and serum or urinary electrolytes (Na and K) with clinical assessment are effective auxiliary elements for diagnosis of hypocortisolism. It is important to bear in mind that circulating cortisol is transported by a cortisol-binding globulin (CBG), susceptible to cross react with other steroids like estrogen or testosterone or become altered in cases of liver disease (acute hepatitis) or hyperthyroidism able to induce high levels of cortisol, making necessary eventually to perform 24-hour urinary collections in order to obtain reliable amounts of free cortisol. Other sources for cortisol analysis that have proved to be useful are those in saliva or hair. Amounts of cortisol measured in saliva seem to be more accurate and specific because cross-reacting CBG is absent; however, experience under circumstances of surgical hypocorticotropism is scarce. Measurements of cortisol in hair apparently provide information to estimate time of tissue exposure to concentrations of cortisol. Potentially, this might be helpful in determining the quantities of hormonal replacement that need reduction or when to decide its withdrawal. Most methods currently available for measuring serum cortisol levels are automated immunoassays or by chemiluminescence, both susceptible to variations derived from cross-reacting material contained in biological fluids and consequently prone to erroneous readings.

Thyrotropin-secreting pituitary tumor presenting with congestive heart failure and good response to dopaminergic agonist cabergoline

Hyperthyroidism is an important inducing factor in patients with atrial fibrillation, and may trigger heart failure. Thyrotropin (thyroid stimulating hormone, TSH)-secreting pituitary tumors are rare causes of hyperthyroidism. Here, we report a 66-year-old man with a pituitary TSH-secreting tumor who presented with hyperthyroidism and congestive heart failure. Endonasal trans-sphenoidal pituitary adenomectomy was performed. After the operation, the symptoms of hyperthyroidism and congestive heart failure were relieved, associated with normalization of thyroid function tests. Unfortunately, hand tremor and progressively elevated free T4 and TSH concentrations recurred 5 months after surgery. A dopaminergic agonist, cabergoline was administered and euthyroidism was restored for at least 11 months.

High-Definition Imaging in Endoscopic Transsphenoidal Pituitary Surgery

The transsphenoidal approach to sellar lesions has evolved enormously since its first description in the early 20th century. Endoscopic surgical strategies have become an integral part of the surgical armamentarium. More recently, high-definition (HD) digital cameras with better image resolution were introduced, although their value for the surgical procedure remains equivocal. The purpose of this study was to compare the image quality of a standard-definition (SD) camera with a new HD camera. A transsphenoidal pituitary adenomectomy was recorded simultaneously in HD and SD resolution. Eight experienced neurosurgeons were asked to identify predefined as well as not predefined anatomic structures in HD and SD. Additionally, the video quality of three complementary surgical sequences was rated with grades from 1 ("very good") to 6 ("poor"). An average of 23.6 ± 2.7 predefined structures (84.38%) were identified in HD versus 17.6 ± 4.4 predefined structures (62.95%) identified in SD. This profound difference in the recognition of anatomic structures reached statistical significance (p = 0.012). Subjective impression of video quality was rated 1.9, 1.9, and 1.4 for the videos in HD and 3.5, 3.3, and 3.5 for the complementary videos in SD. These differences also reached statistical significance (p ≤ 0.005). HD imaging in endoscopic transsphenoidal pituitary surgery accounts for significantly better identification of anatomic structures in comparison with SD images. Additionally, the subjective impression of video quality is significantly better in HD. This improved intraoperative orientation by better digital image quality might contribute to reduce the gap in intraoperative visual accuracy between microsurgery and endoscopy in pituitary surgery.

A Comparative Outcome Analysis of Three-Dimensional (3D) and Two-Dimensional (2D) Endoscopic Transsphenoidal Surgery in the Treatment of Pituitary Adenomas in a Series of 115 Patients

Introduction: Two-dimensional (2D) endoscopes are limited by poor depth perception, lack of stereoscopic vision, and image distortion. Recently, a new three-dimensional (3D) endoscopic system that provides improved stereoscopic vision has been developed. No data exist comparing the results and outcomes of 2D versus 3D endoscopy in treatment of a large cohort of pituitary adenoma patients. We compared the results of transnasal endoscopic pituitary surgery using the 2D and 3D endoscopy systems. Methods: A total of 115 patients underwent endoscopic transnasal transsphenoidal pituitary adenomectomy at Emory University Hospital. In all cases, pituitary tumor resection was performed by a single neurosurgeon (NO). The endoscopic transnasal approach and closure were performed by the otolaryngology service. The 3D endoscopic system was used for pituitary adenomectomy in 72 patients (63%), and the 2D system was used in 43 patients (37%) over a 2-year period. A retrospective analysis included preoperative, perioperative, and postoperative metrics. The statistical comparison was completed using the t test and the chi-square test. Results: The preoperative data for the two groups (3D vs. 2D) is presented: the average age 49.5 versus 45.9, tumor size (all tumors) 6.9 versus 5.8 cm3, and tumor size (macroadenomas) (94/115) 8.3 versus 7.1 cm3 with Knosp cavernous sinus invasion grade of 1.8 versus 1.4. The perioperative data (3D vs. 2D) includes: median operative time of 145 versus 168 minutes, EBL 200 versus 200 mL, LD placement 35/72 (49%) versus 21/43 (49%). The postoperative data (3D versus 2D) includes: hospital stay 5 days versus 5 days, endocrine complications 7/72 (10%) versus 5/43 (12%), CSF leak rate 5/72 (7%) versus 4/43 (9%), remission for functioning tumors was 20/30 (67%) versus 12/21 (57%), readmission rate was 15/72 (21%) versus 10/43 (23%), reoperation rate was 4/72 (6%) versus 8/43 (19%), and transsphenoidal CSF leak repair 0/72 (0%) versus 3/43 (7%). The reoperation rate and the CSF leak repair rate were statistically different (P < 0.03, chi-square). The other metrics were not statistically different. Conclusions: Three-dimensional endoscopy improves the depth of field and provides stereoscopic vision. This improvement resulted in a statistically significant decrease in overall reoperation and CSF leak repair rate in our series.

Use of morning serum cortisol level after transsphenoidal resection of pituitary adenoma to predict the need for long-term glucocorticoid supplementation

Accurate assessment of the hypothalamic-pituitary-adrenal (HPA) axis is critical for appropriate management of the disease in patients with pituitary adenoma after transsphenoidal resection. The authors examine the role of the morning total serum cortisol level in the early postoperative period as a predictor of long-term HPA function. Morning total serum cortisol was measured in 83 patients on postoperative Day 1 (or Day 2 if the patient received glucocorticoids during surgery) after transsphenoidal surgery for pituitary adenoma. These results were compared with those of definitive assays of HPA function performed at 1-3 months postoperatively, including cortrosyn/synacthen stimulation test (CST), insulin tolerance test (ITT), and metyrapone test (MTT). The ability of the early-postoperative morning cortisol level to predict HPA function was determined using standard confusion matrix calculations and receiver-operator control curve analysis. The authors found that an early postoperative morning total cortisol level>or=15 microg/dl is a sensitive and accurate predictor of normal HPA function in the postoperative period (sensitivity 80.5%, specificity 66.7%, positive predictive value 96.9%). A morning total cortisol level>or=15 microg/dl in the early postoperative period after transsphenoidal surgery for pituitary adenomas is a good predictor of normal HPA function. This test has good sensitivity and accuracy and correlates well with the results of additional, definitive assays of HPA function (CST, ITT, and MTT) performed at 1-3 months postoperatively. Accordingly, it is the authors' practice to avoid exogenous perioperative glucocorticoid supplementation in patients with normal preoperative HPA function and postoperative morning total cortisol levels>or=15 microg/dl 1-2 days after transsphenoidal pituitary adenomectomy.

Prospective evaluation of a protocol for reduced glucocorticoid replacement in transsphenoidal pituitary adenomectomy: prophylactic glucocorticoid replacement is seldom necessary

Most pituitary surgery centres prescribe perioperative glucocorticoids to subjects undergoing transsphenoidal pituitary adenomectomy (TSA), despite reports suggesting this may be unnecessary. Evidence-based guidelines for glucocorticoid use in TSA have recently been published but there are no prospective studies of their utility. To implement and assess a protocol for reduced glucocorticoid replacement for subjects undergoing TSA. Prospective and retrospective cohort study in an Australian pituitary surgery centre. Clinical and biochemical data for 56 TSAs performed for non-ACTH-secreting tumours between March 2004 and April 2006 were prospectively collected and compared with data for 47 TSAs performed between October 2001 and November 2003, before implementation of the protocol. In the prospective cohort, a postoperative days 1-3 morning serum cortisol threshold of 250 nmol/l (91 microg/dl) was used to guide long-term glucocorticoid requirement. Implementation of the protocol was associated with significant reductions in dose and duration of glucocorticoid treatment post TSA in 44 'low-risk' cases (no preoperative glucocorticoid use or evidence of pituitary apoplexy). In two low-risk cases, long-term glucocorticoid replacement was required despite postoperative cortisol greater than 250 nmol/l. Following the remaining 42 low-risk operations, glucocorticoid was not prescribed on hospital discharge on the basis of morning serum cortisol > 250 nmol/l and no clinical evidence of hypocortisolism. None of these 42 cases required glucocorticoid treatment for hypocortisolism following surgery. Short synacthen tests were performed in 35 of these subjects a minimum of 6 months after surgery and were normal. Use of the protocol was not associated with differences in postoperative complications. Reduced glucocorticoid replacement in TSA is safe and reduces patient exposure to glucocorticoids and their potential adverse events. The occurrence of hypocortisolism in two low-risk subjects with serum cortisol > 250 nmol/l highlights the importance of daily clinical assessment when using this protocol.

Preliminary Experience with 3-Tesla MRI and Cushing's Disease

Because radiographic visualization of a pituitary microadenoma is frequently difficult, we hypothesized that microadenomas associated with Cushing's disease may be better resolved and localized via acquisition with 3-Tesla (3T) compared with standard 1.5-Tesla (1.5T) magnetic resonance imaging (MRI). Five patients (four females, one male; age range, 14 to 50 years old) with endocrine and clinical confirmation of Cushing's disease underwent 1.5T and 3T MRI and corticotropin-releasing hormone stimulation/inferior petrosal sinus sampling (IPSS) as part of their preoperative evaluation. All patients underwent a transnasal trans-sphenoidal pituitary adenomectomy. In two cases, tumor could not be localized on either 1.5T or 3T MRI on the initial radiologist's review. In two other cases, the 1.5T images delineated the tumor location, but it was more clearly defined on 3T MRI. In a fifth case, the 1.5T MRI showed a probable right-sided adenoma. However, on both 3T MRI and at surgical exploration the tumor was localized on the left side. Therefore, in three of five cases, 3T MRI either more clearly defined tumors seen on 1.5T MRI or predicted the location of tumor contrary to the 1.5T images. IPSS identified the correct side of the tumor in two patients, an incorrect location in two patients, and was indeterminate in one patient. In certain cases 3T MRI is a new tool that may ameliorate imaging difficulties associated with adrenocorticotrophic hormone-secreting pituitary adenomas. Its role in the diagnostic evaluation of Cushing's disease will be better defined with further experience.

ACTH-dependent Cushing's syndrome: a revision of 43 cases

To evaluate the characteristics and outcomes of the patients diagnosed as ACTH-dependent Cushing syndrome, registered in the department. We reviewed the files of forty-three patients followed from 1974 to 2002. A progressive rise in the number of patients diagnosed was found, being 80% females. Clinical suspicion was based mostly on the typical fat distribution; hirsutism and amenorrhoea were important in women. The more reliable diagnostic tests were: 11 pm cortisol, day curve of ACTH and cortisol, and dexamethasone suppression tests. The ACTH response to CRH during inferior petrosal sinus sampling permitted the diagnosis of ectopic source. In thirty-seven patients a pituitary adenoma was diagnosed. The three patients diagnosed before 1985 went for bilateral adrenalectomy (Nelson's syndrome in two); the others were submitted to transsphenoidal pituitary adenomectomy, obtaining remission in twenty six at the first operation and in two others at the second. Three patients had a recidive. Of the six patients with persistent disease (all treated with metyrapone or ketoconazole), three were submitted to radiotherapy, two to bilateral adrenalectomy, and one was waiting for surgery. Four patients had a bronchial carcinoid, successfully removed in three. One patient was lost to follow-up and another was still being evaluated. We found a positive evolution in the capacity to diagnose and treat these patients. Neurosurgical ability to achieve remission was 80% in the operated cases. More effective technical methods and drugs, as well as a multidisciplinary and dedicated medical team, lead to long lasting remissions in most of the patients.