Suprasellar Pituitary Adenoma Research Articles

504 Anterior-posterior Diameter Is a Key Driver of Resectability and Complications for Pituitary Adenomas With Suprasellar Extension in Endoscopic Transsphenoidal Surgery

INTRODUCTION: As endoscopic transsphenoidal approaches are more routinely selected for larger pituitary adenomas with parasellar extension, understanding potential anatomical factors that limit resection and contribute to complications becomes increasingly important. METHODS: A single-center retrospective review of all endoscopic transsphenoidal surgeries for pituitary adenomas with suprasellar extension from 2015-2020 was performed. Preoperative MRIs were systematically assessed to assign a Knosp classification, a Zurich Pituitary Score (ZPS), and to measure lesional suprasellar dimensions. Univariate comparisons and multivariate regression models were employed to assess the influence of these factors on extent of resection (EOR) and postoperative complications. RESULTS: Of the 96 patients with suprasellar pituitary adenomas who underwent endoscopic transsphenoidal surgery, 74 patients (77%) had a gross total resection (GTR). Neither Knosp grade nor ZPS were associated with GTR (Knosp 3A-4 versus Knosp 0-2, p = 0.069; ZPS III-IV versus ZPS I-II, p = 0.079). Multivariate regression identified suprasellar anterior-posterior tumor diameter (SSAP) as the only significant predictor of EOR (OR 0.951, 95% CI 0.905-1.000, p = 0.048*). Higher SSAP also showed the strongest association with an increased overall complication rate (p = 0.0003*) and intraoperative CSF leaks (p = 0.0012*). Further analysis of the regression model for GTR suggested an optimal cut point value for SSAP of 23.7 mm, above which predictability for failing to achieve GTR carried a sensitivity of 89% and specificity of 41%. CONCLUSIONS: This study is unique in its examination of endoscopic transsphenoidal surgical outcomes for pituitary adenomas with suprasellar extension. Our findings suggest that previously established grading systems based on lateral extension into the cavernous sinus lose their predictive value in lesions with suprasellar extension and, more specifically, with increasing suprasellar anterior-posterior diameter.

Anterior-posterior diameter is a key driver of resectability and complications for pituitary adenomas with suprasellar extension in endoscopic transsphenoidal surgery.

As endoscopic transsphenoidal approaches are more routinely selected for progressively larger pituitary adenomas with parasellar extension, understanding potential anatomical factors that limit resection and contribute to complications is becoming increasingly important for tailoring a surgical approach. This study aimed to reevaluate existing predictive tools for resectability in pituitary adenomas specifically with suprasellar extension, and furthermore identify any additional measurable features that may be more useful in preoperative planning. A single-center retrospective chart review of adult patients who underwent endoscopic transsphenoidal surgery for pituitary adenomas with suprasellar extension from 2015 to 2020 was performed. Preoperative MRIs were systematically assessed to assign a Knosp classification, a Zurich Pituitary Score (ZPS), and for dimensional measurements of the suprasellar aspect of the lesions. Univariate comparisons and multivariate regression models were employed to assess the influence of these factors on extent of resection and postoperative complications. Of the 96 patients with suprasellar pituitary adenomas who underwent endoscopic transsphenoidal surgery, 74 patients (77%) had a gross total resection (GTR). Neither Knosp grade nor ZPS score, even when dichotomized, demonstrated an association with GTR (Knosp 3A-4 versus Knosp 0-2, p = 0.069; ZPS III-IV versus ZPS I-II, p = 0.079). Multivariate regression analysis identified suprasellar anterior-posterior tumor diameter (SSAP) as the only significant predictor of extent of resection in this cohort (OR 0.951, 95% CI 0.905-1.000, p = 0.048*). A higher SSAP also had the strongest association with intraoperative CSF leaks (p = 0.0012*) and an increased overall rate of postoperative complications (p = 0.002*). Further analysis of the regression model for GTR suggested an optimal cut point value for SSAP of 23.7mm, above which predictability for failing to achieve GTR carried a sensitivity of 89% and a specificity of 41%. This study is unique in its examination of endoscopic transsphenoidal surgical outcomes for pituitary adenomas with suprasellar extension. Our findings suggest that previously established grading systems based on lateral extension into the cavernous sinus lose their predictive value in lesions with suprasellar extension and, more specifically, with increasing suprasellar anterior-posterior diameter.

Suprasellar pituitary adenomas: a 10-year experience in a single tertiary medical center and a literature review.

Suprasellar pituitary adenomas (SPAs) are a special type of pituitary adenoma. Although dozens of SPA cases have been reported, the exact definition and the characteristics of SPA have not been exhaustively discussed before. In a retrospective electronic medical records review, 13 patients with SPA were identified in our hospital between January 2010 and December 2019. A literature review was performed by searching the online database PubMed, and 39 cases conformed to the criteria based on the previous literature. Data regarding clinical symptoms, imaging manifestations, surgical information and follow-ups were analyzed. The mean age at diagnosis of 52 patients with SPA was 36.73 years, and most of the patients were female (61.5%). The most common hormone-secreting subtypes of SPA were nonfunctioning (36.5%) and ACTH-secreting (34.6%) SPA. Macroadenomas (68.9%) were more common than microadenomas (31.1%). The origins of the SPAs included the intrasellar pituitary gland (type I), the subdiaphragmatic (type IIa) and supradiaphragmatic (type IIb) part of the pituitary stalk, and the suprasellar peri-infundibular region (type III). The most common anatomic subtype of SPA was type III, and type IIb was also common. The most common presentations of SPA were visual symptoms, especially for type III SPA. In addition, 64.7% and 73.1% of type IIb and III SPAs, respectively, were suspected to be of suprasellar origin based on presurgical imaging examination. Patients with tumors of suspected suprasellar origin were more likely to receive transcranial surgery (TCS) initially than those with tumors of suspected intrasellar origin (70.6% vs. 22.2%, p = 0.0013). The intact rate for the pituitary stalk after surgery for type II SPA was lower than that for type I and III SPA (52.6% vs. 92.6%, p = 0.0036). More patients with type II SPA experienced postoperative central diabetes insipidus (CDI) than those with type I and III SPA (57.9% vs. 11.1%, p = 0.0011). There was no significant difference in the incidence of postoperative CDI between transsphenoidal surgery (TSS) and TCS (p = 0.1304). Nine patients in our hospital received extended endoscopic TSS; only one experienced tumor recurrence, and no severe complications occurred after surgery. SPAs could be defined as pituitary adenomas completely or partially located in the suprasellar region. There were both similarities and differences among the different anatomic subtypes of SPA. For patients who were suspected of having SPAs, visual field tests, pituitary hormone evaluation and MRI were necessary. Because imaging examination is not a reliable method, surgery is the only way to confirm the tumor origin. Extended endoscopic TSS might be a safe and efficient approach to remove these tumors, but more studies are needed to verify this conclusion. For type II SPA, the pituitary stalk should be carefully protected during surgery, and postoperative CDI should be monitored.

Clinical study of endoscopic treatment of a sellar pituitary adenomas with sellar diaphragm defect

BackgroundInvasive growth of pituitary macroadenomas to the suprasellar region occurs commonly. Pituitary adenomas show varying growth patterns when the sellar diaphragm is absent, and they are often confused with other common tumors in the sellar region. This article explores the clinical features of suprasellar pituitary adenomas with defects of the sellar diaphragm (SPADSD) and evaluates the efficacy of the endoscopic endonasal approach (EEA) for treatment of such tumors.MethodsWe performed a detailed examination of records from 19 patients collected prior to surgery. After relevant diseases were excluded, the tumor properties were evaluated according to imaging characteristics. Diagnoses were verified using EEA surgery. The concept of SPADSD was put forward. Postoperative recovery was followed to determine whether EEA is suitable for the treatment of such tumors.ResultsIn the 19 patients with SPADSD, we found that the tumors were less stressed on the pituitary, and tumors in the suprasellar region often had irregular shapes. During surgery, we took extended supra-saddle approaches and confirmed that unrestricted growth of the tumor was caused by defects in the diaphragm of the sella turcica to the suprasellar region. Recovery was good after surgery, confirming the efficacy of EEA for treatment of these tumors.ConclusionSPADSD has different clinical features from those of other pituitary tumors and requires careful screening prior to surgery. Endoscopic surgery is the preferred procedure for this type of tumor.

‘Ectopic’ suprasellar type IIa PRL-secreting pituitary adenoma

Ectopic pituitary adenomas (EPAs) are rare, and the suprasellar cistern seems to be the most common location. At this time, no detailed original classification, diagnosis, or treatment protocols for suprasellar pituitary adenomas (SPAs) have been described. A 19-year-old man showed visual disturbances and lack of libido for 3years, he suffered a sharp decline in vision with only light perception in the last week. Magnetic resonance imaging scans revealed a large suprasellar cystic lesion with a normal pituitary in the sella turcica. Endocrinological findings showed an extremely high prolactin level of 1250ng/mL. Because of the sharp decline in vision, the patient underwent total removal of the suprasellar lesion using a transfrontal interhemispheric approach. The tumor pedicle originated in the lower pituitary stalk without any connection to the anterior pituitary gland in the sella turcica, while the diaphragma sellae was incomplete. Clinical and endocrinological cure criteria were fulfilled and postoperative pathology confirmed a prolactin-secreting pituitary adenoma. Ectopic suprasellar pituitary adenomas (ESPAs) are extremely rare intracranial extracerebral tumors. SPAs can be classified into three types according to their origin and their relationship with surrounding tissue. Only type III is theoretically a true ectopic, based on previous reports. Thus, ESPAs are uncommon compared to other EPAs. Our case is the first reported case of a type IIa 'E'SPA and the first description of this subtype classification until now. The pars tuberalis may be different from the pars distalis, and each subtype of adenohypophyseal cells may have different migration characteristics, which leads to different proportions of each hormone-secreting subtype in SPAs and EPAs. Transsphenoidal surgery is minimally invasive, but transcranial surgery may remain a universal option for the treatment of suprasellar lesions.

A Comparison among the Effectiveness of Growth Hormone Suppression in Active Acromegaly of Bromocriptine and Long Acting Somatostatin Analogue (SMS 201–995)

The aim of our study was to compare the effectiveness of bromocriptine vs. long acting somatostatin analogue (SMS 201-995) on growth hormone suppression in active acromegaly. A twenty year old female, student of law, was previously treated with Parlodel LA 50 mg i.m. injection and then with bromocriptine 30 mg orally for 2.5 years because of active acromegaly and very large intrasellar and suprasellar pituitary adenoma. She was partial bromocriptine responder with mean growth hormone levels prior the treatment 30 mU/L and after bromocriptine 13.7 mU/L and with gross tumor shrinkage. Since she failed to restore menstrual cycles, had clinical signs of the disease, she was taken off bromocriptine and treated with somatostatin analogue (SMS 201-995) 300 mcg s.c. daily and 400 mcg s.c. daily with mean growth hormone levels 10 mU/L. She was also treated with combined treatment (400 mcg s.c. SMS 201-995 plus 30 mg bromocriptine orally) and mean growth hormone levels were 11 mU/L. SMS 201-995 had a long lasting inhibitory effect on growth hormone secretion in acromegaly (p less than 0.01) but in comparison to daily growth hormone levels during bromocriptine treatment no difference was found (p greater than 0.01). Combined treatment with SMS 201-995 and bromocriptine did not achieve greater suppression of daily growth hormone levels than those achieved with SMS 201-995 alone (p greater than 0.1) or with bromocriptine alone (p greater than 0.05). No significant tumor shrinkage during chronic SMS treatment was seen. Severe clinical and biochemical signs of hypoglycaemia were registered on one occasion only during the first month of treatment with SMS 201-995.(ABSTRACT TRUNCATED AT 250 WORDS)

Eyelid approach to the anterior cranial base

Skull base approaches play a fundamental role in modern neurosurgery by reducing surgical morbidity. Increasing experience has allowed surgeons to perform minimally invasive approaches without straying from the premises of skull base surgery. The eyelid approach has evolved from the orbitopterional osteotomy into a more effective and targeted approach to disease of the anterior cranial fossa. In this technique, after an incision is made on the supratarsal fold, the orbicularis oculi muscle is incised, and a myocutaneous flap composed of the elements of the anterior lamella is elevated. Subperiosteal dissection is used to expose the superior and lateral walls of the orbit, the superior and lateral orbital rim, and the frontosphenoidal suture. A MacCarty bur hole is drilled, and a frontal osteotomy is fashioned medial to the supraorbital notch and extending through the orbital roof back toward the orbital half of the MacCarty bur hole, exposing the frontobasal brain. A conventional microsurgical technique is used to treat tumors and aneurysms of the anterior cranial fossa under the operative microscope. Five patients were treated for unruptured aneurysms of the anterior circulation (3 anterior communicating artery aneurysms, 1 ophthalmic artery aneurysm, and 1 posterior communicating artery aneurysm) using the eyelid approach. The mean aneurysm size was 5 mm, and all aneurysms were approached from the right side. Three tumors in the anterior fossa (2 suprasellar pituitary adenomas and 1 craniopharyngioma) were also excised using this approach. There was no surgical morbidity. Three months after surgery all patients presented excellent cosmetic results. The eyelid approach may be considered as an effective, cosmetically beneficial, and minimally invasive skull base approach to selected aneurysms and tumors of the anterior circulation.

Nonfunctioning pituitary adenoma: incidence, causes of death and quality of life in relation to pituitary function

The incidence of clinically significant, nonfunctioning pituitary adenoma, requiring surgical treatment, has not been established. According to previous studies, both surgery type and subsequent radiotherapy may have an impact on quality of life (QOL), and some studies have shown increased cardiovascular mortality in patients with pituitary disease. We studied all patients with functionless, suprasellar pituitary adenoma who were operated on during the period 1985-1996 (N = 192; transsphenoidal surgery = 160, craniotomy = 32). QOL was evaluated from Short Form 36 and Major Depression Inventory questionnaires. Causes of death were obtained from the Danish Register of Causes of Death. Incidence was 5.6/mill/year. Postoperatively, 27% of the patients had normal pituitary function and 27% were panhypopituitary. Fifty three patients had died. Death from cardiovascular, cerebrovascular and malignant diseases was not increased. Overall, QOL was not different from QOL of an age- and sex matched background population. QOL was, however, impaired in patients who had undergone craniotomy as compared to patients undergoing transsphenoidal surgery. QOL was not reduced in hypopituitary patients or in patients receiving radiotherapy.

Objective criteria for successful transsphenoidal removal of suprasellar nonfunctioning pituitary adenomas. A prospective study

Despite ample experience with transsphenoidal surgery, objective data on which suprasellar tumour expansion and growth pattern allows for radical adenoma resection are still sparse. Hence, we have performed a prospective study to establish the predictive value of tumour dimension and shape for the intra-operative descent of the diaphragma, the completeness of tumour resection and the outcome of patients harbouring pituitary adenomas with suprasellar extension. Included in the study were 105 patients with nonfunctioning pituitary adenomas and suprasellar extension who underwent primary transsphenoidal surgery between January 1998 and December 2005. The precise suprasellar extension, the degree of dumbbell-shape, the configuration of the adenomas and the depth of the pituitary fossa were evaluated. Completeness of resection was assessed by MRI at 3 months postoperatively. The mean cranio-caudal diameter of the tumours was 28.0 mm (range 9.2-57.8 mm). On average, the suprasellar extension measured 11.9 mm (range 2.1-25.8 mm). Total removal of the suprasellar tumour was accomplished in 83% (87 of 105) of the patients. A second operation for residual adenoma was only indicated in 2 cases. The vertical intracranial extension was the strongest independent predictor of subtotal resection (p < 0.001). Irregular and multilobular configuration was a second highly-significant and independent predictor for incomplete resection (p < 0.003). In contrast, dumbbell-shape and shallow pituitary fossa were not independent predictive factors for incomplete tumour resection. The complication rate was very low. None of our patients suffered postoperative rhinorrhea, meningitis or visual deterioration. One-stage transsphenoidal surgery allows total or near-total resection of most suprasellar pituitary adenomas with low surgical morbidity. Quantitative assessment of tumour dimension and configuration contributes to establishing guidelines for the selection of the appropriate approach and prediction of surgical outcome.

Hypopituitarism and mortality in pituitary adenoma

Previous studies on hypopituitarism and mortality have concluded that insufficient pituitary function is associated with decreased survival. For several reasons the results are difficult to compare - particularly because definitions and treatment of hypopituitarism have varied and various underlying disorders have been included. The purpose was to assess the relationship between mortality and pituitary function. One hundred and sixty consecutive patients (99 men and 61 women) with functionless, suprasellar pituitary adenoma. All were operated on transsphenoidally during the period 1985-1996. Additional radiotherapy was given to 29 patients. Mortality was calculated 12.4 years (median, range 8.1-19.9) after operation. Postoperative hormonal deficits were treated in most, though GH substitution was given only to a minority of patients. Postoperatively 30% of the patients had normal pituitary function (normal adrenocortical, thyroid and gonadal function), 26% were panhypopituitary and 36% had partial pituitary insufficiency. Forty-one patients had died (34.7 expected) yielding a standard mortality ratio (SMR) of 1.18 (95% confidence limits (CI) 0.87-1.60). SMR was significantly increased in women (1.97, CI 1.20-3.21) but not in men (0.83, CI 0.55-1.26). SMR in patients with normal pituitary function, panhypopituitarism and partial insufficiency were not different from that in the general population. SMR in hypopituitary women was substantially higher than in men with pituitary insufficiency. Treatment with growth hormone in GH-deficient patients did not influence survival. Pituitary surgery for nonfunctioning adenoma and subsequent pituitary insufficiency had no effect on mortality in men, but was associated with significantly increased mortality in women. Suboptimal hormonal substitution in women may play a role.

Chiasmal pathology causing inability to access information in the temporal visual field

Background: A series of four patients with evidence of chiasmal pathology were found to be unable to access information in the temporal visual field. Only the optotypes in the nasal field were seen during monocular testing of acuity; the letters in the temporal visual field remained unseen. Moreover, the process of reading was found to be significantly impaired in three of the four patients. Methods: Conventional distance visual acuity testing and visual field assessments were carried out. Three patients had undergone surgery for tumor adjacent to the optic chiasm (one craniopharyngioma and two suprasellar pituitary adenomas). One patient had sustained permanent minute paracentral bitemporal scotomata after head injury. Results and conclusions: In each case, only printed material in the nasal visual field was observed by the patients during monocular viewing even though there was no restriction of horizontal eye movements.This defective visual behavior affected both eyes in three patients and was unilateral in one.The disturbance was reversible after surgery for pituitary adenoma in one case, but was longstanding in three. It is hypothesized that the defective visual behavior is related to an associated cognitive lack of spatial awareness and compensation for the visual field defect possibly due to a disturbance of visual reflex search mechanisms. Recognition of the specific visual behavior in patients during routine eye examination should arouse diagnostic attention to lesions of the chiasm.

鼻側半盲を呈した鞍上部異所性下垂体腺腫の1例

鼻側半盲を呈した鞍上部異所性下垂体腺腫の症例を経験した.症例は40歳,男性で,左眼の視力低下を主訴に来院した.初診時左眼の鼻側半盲を認めた.頭部単純X線ではトルコ鞍の平皿状変化を示し,MRIでは鞍上部の腫瘍ならびにそれとの間に明瞭な境界を有する正常下垂体が確認された.術中所見では腫瘍と下垂体茎とは境界明瞭,腫瘍と鞍隔膜の軽度癒着は認めたが,トルコ鞍内との連続性はみられなかった.腫瘍は肉眼的に全摘された.病理診断は下垂体腺腫であった.術後の内分泌学的検査では下垂体前葉機能は保持されていた.画像所見,術中所見,病理所見および術後の内分泌学的所見から,鞍上部異所性下垂体腺腫と診断した.

プロラクチンおよび成長ホルモンを産生し嚢胞を伴った異所性鞍上部下垂体腺腫

プロラクチン(PRL)および成長ホルモン(GH)を産生し, 鞍上部に発生した異所性下垂体腺腫種を経験した.開頭手術によりほぼ全摘を行い, 症状と内分泌学的治癒をもたらしたので報告した.症例は22歳, 女性で, 頭痛, 視力障害そして無月経を主訴として来院した.MRIにて鞍上部に直径が各2×3×2.5cmのniveau formationを示す嚢胞性腫瘍を認め, 鞍隔膜によって正常下垂体とは分けられて観察された.下垂体ホルモン検査では血清プロラクチンとGHの基礎値が高値を示し, TRH, LH-RHおよびヒトインスリンによる下垂体刺激試験には低反応であった.一方, 血清ACTH, TSH, LH, FSHの基礎値は低値を示し, 下垂体刺激試験に対し低反応を示した.術中所見では腫瘍は正常下垂体との連続性がなく, pars tuberalisより発生したものと考えられた.病理学検査においては, 免疫染色も含め, プロラクチンと成長ホルモン陽性の下垂体腺腫と診断した.下垂体ホルモン術後検査ではPRL基礎値は低値となり, 下垂体刺激試験にも低反応となった.他のホルモンは基礎値および下垂体刺激試験ではともに正常化した.術後頭痛, 視力障害は消失し, 6カ月後には規則正しい月経も再来し, 腫瘍の全摘が目指されるべきであると考えられた.

Adjuvant γ-Knife Radiosurgery for a Resected Suprasellar Pituitary Adenoma with Atypical Immunohistochemistry: Case Report

A resected suprasellar mass was found to be an ectopic pituitary adenoma on light microscopy, but immunohistochemistry revealed unusual staining patterns. Residual disease was demonstrated on postoperative studies and γ-knife radiosurgery was used for treatment. The literature on ectopic pituitary tumors was reviewed. We concluded that postoperative stereotactic radiosurgery (SRS) for ectopic, suprasellar pituitary adenomas (and variants thereof) is an appropriate management option for persistent disease.

On “Adjuvant γ-Knife Radiosurgery for a Resected Suprasellar Pituitary Adenoma with Atypical Immunohistochemistry: Case Report” (Videtic et al., This Issue)

On “Adjuvant γ-Knife Radiosurgery for a Resected Suprasellar Pituitary Adenoma with Atypical Immunohistochemistry: Case Report” (Videtic et al., This Issue)

Comparison of thermoregulatory characteristics of patients with intra- and suprasellar pituitary adenomas.

Thermoregulatory capabilities under physiologic cold and heat exposure of 37 patients with suprasellar pituitary adenomas (As) and 10 patients with intrasellar adenomas (Ai) were analyzed and compared to each other and to 13 controls (Ctr.) In Ai no shift of the thermoregulatory threshold temperatures was observed. In As the regulation was shifted to a 0.5 degrees C higher mean body temperature in 82% of the patients, indicating a "set-point" elevation. The accuracy of the regulation against thermal loads was maintained, the velocity was reduced. Postoperative examination of As revealed a normalisation of the "set-point". Modifications of the hypothalamic amine systems by the compressive effect of the suprasellar adenomas are discussed to be the most probable cause for the observed thermoregulatory alterations.

MODIFICATIONS OF THERMOREGULATION IN PATIENTS WITH SUPRASELLAR PITUITARY ADENOMAS

Thermoregulation was investigated pre and postoperatively in 5 and only preoperatively in 7 patients with suprasellar pituitary adenomas by exposing them to external cold and heat in a climatic chamber. Five healthy subjects served as controls. Body core and skin temperatures, oxygen consumption, electromyographic activity, skin blood flow and local sweating rates were continuously measured. Threshold temperatures for activation of heat production and heat loss were calculated from these data. Hormone analysis was performed before and after stimulation with releasing factors. In the patients, core temperatures as well as threshold temperatures for heat production and heat loss were elevated by about 0.5 degrees C as compared with controls. This elevation of core and threshold temperatures was achieved, despite a reduced resting metabolic rate, by a reduction of skin blood flow indicated by a low mean skin temperature. After successful operation the thermoregulatory alterations normalized. Serum levels of growth hormone were reduced preoperatively and stimulation by GHRF did not cause an appropriate increase. Prolactin was elevated in 6 patients with prolactinomas, but there was no correlation with changes in thermoregulatory threshold temperatures. Stimulation of the other hypophyseal hormones by the combined anterior pituitary function test revealed a normal hormonal response. Apart from prolactin there were no significant hormonal changes postoperatively. It is concluded that disturbances of temperature regulation are present in patients with suprasellar adenomas, but that they are not detectable by routine clinical methods. These alterations probably depend on a disturbance of hypothalamic function and are reversible by surgery.

Suprasellar pituitary adenoma arising from the pars tuberalis

A rare case of suprasellar pituitary adenoma arising from the pars tuberalis in a 53-year-old woman is presented. The tumor was located exclusively above the diaphragma sellae, and no invasion into the sella turcica was noted.

Suprasellar Pituitary Adenoma Arising from the Pars Tuberalis: Case Report

Abstract A rare case of suprasellar pituitary adenoma arising from the pars tuberalis in a 53-year-old woman is presented. The tumor was located exclusively above the diaphragma sellae, and no invasion into the sella turcica was noted.

Differentiation of large suprasellar masses by evaluation of the superior margin

Differentiation of suprasellar masses by computed tomography criteria depends on intrasellar extension, patterns of calcification and enhancement, associated bony reaction, and cystic changes. In the case of a homogeneously enhancing suprasellar mass that does not exhibit any of these differentiating findings, separating a suprasellar meningioma from a large suprasellar pituitary adenoma has been quite difficult. We reviewed the computed tomography findings of 42 such tumors. There were 19 meningiomas and 23 pituitary adenomas chosen that had few or none of the commonly applied findings used in differentiation. Evaluation of the superior contour of these masses seems a reliable sign to use in this situation. A single upward convex curve correlated with a meningioma in 15 of 19 cases (78%), whereas a multiple upward convex curve correlated with a pituitary adenoma in 19 of 23 cases (82%). Although some pitfalls were encountered when employing this sign—such as pseudolobulations caused by the adjoining cavernous sinus, dural, or vascular structures—it nonetheless led to the correct diagnosis in approximately 80% of cases.