[A Case of Intradural Retroclival Chordoma].

A 67-year-old woman was referred to our department with a retroclival lesion including a cyst on MRI. MRI revealed a lesion appearing as an isointense region on a diffusion-weighted image(DWI). Gadolinium(Gd)-DTPA T1-WI showed heterogeneous enhancement of the lesion in the prepontine cistern. Computed tomography(CT)revealed an isodense lesion with no invasion into the clival bone. Based on a preoperative diagnosis of retroclival chordoma, extended trans-sphenoidal surgery(TSS)was performed by a direct endoscopic endonasal approach via the left nostril. We found a round dural defect with a diameter of 5 mm, through which the tumor was incarcerated. However, the tumor had no connection to the clival bone. The lesion was totally removed and histologically diagnosed as a chordoma. Furthermore, the clival bone included no tumor cells. Based on those radiological and histological findings, we diagnosed the lesion as an intradural retroclival chordoma. We should consider intradural retroclival chordoma as a candidate for the differential diagnosis of a retroclival lesion without clival bone invasion.

Solitary Langerhans cell histiocytosis located in the neurohypophysis with a positive titer HCG-ß in the cerebrospinal fluid.

INTRODUCTION: Beta-human chorionic gonadotropin (HCG-ß) is considered to be a useful tumor marker for germ cell tumors (GCTs); however, various tumors other than GCTs, including cystic pituitary adenomas, Rathke's cleft cysts, and craniopharyngiomas, were reported to express HCG-ß. CASE REPORT: We herein present the case of a 5-year-old boy who presented with polyuria and had a solitary lesion in the neurohypophysis with a positive HCG-ß titer in the cerebrospinal fluid. Under a preoperative diagnosis of germinoma, a biopsy was performed from the posterior pituitary lobe via the transsphenoidal endoscopic approach and the histological diagnosis was revealed to be Langerhans cell histiocytosis (LCH). CONCLUSIONS: The finding of a slightly positive HCG-ß titer in the cerebrospinal fluid (CSF) cannot exclude the possibility of LCH, and we strongly recommend a histological diagnosis for the diagnosis of a solitary neurohypophysial lesion.

Diffusion-weighted imaging and the apparent diffusion coefficient on 3T MR imaging in the differentiation of craniopharyngiomas and germ cell tumors.

The apparent diffusion coefficient (ADC) on diffusion-weighted imaging (DWI) plays an important role in diagnosing intracranial tumors and predicting the histopathological grade of the tumor. However, the differences in the ADC values between craniopharyngiomas and germ cell tumors (GCTs) have not been clarified. We therefore evaluated the DWI and ADC values at b = 1000 and b = 4000 s/mm(2) on 3T magnetic resonance (MR) imaging and assessed the possibility of differentiating between craniopharyngiomas and GCTs. We retrospectively reviewed 19 patients with craniopharyngioma and 24 patients with GCT who underwent surgery and received a histopathological diagnosis. Thirty-four patients underwent DWI with b = 1000 and b = 4000 s/mm(2) and nine patients underwent periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) DWI with b = 1000 s/mm(2). The ADC was determined by manually placing regions of interests (ROIs) in the respective tumor regions on the ADC maps and is expressed as the minimum (ADC(MIN)), mean (ADC(MEAN)), and maximum (ADC(MAX)) absolute values. The craniopharyngiomas showed lower intensity on DWI at b = 1000 and b = 4000 s/mm(2) than the GCTs. Furthermore, the craniopharyngiomas demonstrated significantly high ADC values (ADC(MIN), ADC(MEAN), and ADC(MAX)) in comparison with the GCTs on DWI at b = 1000 and b = 4000 s/mm(2). The logistic discriminant analysis clarified the advantage of ADC(MIN) at b = 4000 s/mm(2) in differentiating between craniopharyngiomas and GCTs compared with the other ADC values. DWI and the ADC values may help clinicians to differentiate between craniopharyngiomas and GCTs. The ADC(MIN) at b = 4000 s/mm(2) is particularly useful for differentiation.

Clinical features and natural course of acromegaly in patients with discordance in the nadir GH level on the oral glucose test and the IGF-1 value at 3 months after adenomectomy.

Discordant GH and IGF-1 levels after adenomectomy are well recognized in acromegalics. The aim of this study was to evaluate the clinical features and natural course of postoperative acromegaly associated with discordant GH and IGF-1 levels over a postoperative period. A total of 69 acromegalics underwent surgery with at least 1 year of follow-up and received 75-g oral glucose tolerance tests (OGTTs) at 3 months postoperatively. The patients were categorized into four groups according to the postoperative nadir GH levels and IGF-1 levels: controlled group (normal GH and normal IGF-1), high-IGF-1 group (normal GH and high IGF-1), high-GH group (high GH and normal IGF-1), and uncontrolled group (high GH and high IGF-1). The incidence of discordant GH and IGF-1 levels was 27.5%: high-IGF-1 group = 10.1% (n = 7) and high-GH group = 17.4% (n = 12). All patients in the high-IGF-1 group exhibited a decline in the IGF-1 level after surgery, with normalization observed in 71.4% of the patients without additional treatment (median 23 months). These subjects had preoperatively high IGF-1 levels despite not demonstrating higher GH levels than the patients in the controlled group. On the other hand, four patients in the high-GH group exhibited an elevated nadir GH level higher than 1.0 µg/L on repeated OGTTs after 3 months, and one patient experienced a recurrence of acromegaly. Patients in the high-IGF-1 group require no additional treatments, and their IGF-1 levels are likely to normalize within a few years. However, patients in the high-GH group should be carefully followed due to the possibility of recurrence.

Impact of subclinical haemorrhage on the pituitary gland in patients with pituitary adenomas.

OBJECTIVE: Advanced magnetic resonance imaging (MRI) and optical instruments for surgery frequently demonstrate subclinical haemorrhage in pituitary adenomas; however, the effects of subclinical haemorrhage on pituitary glands remain unclear. We sought to clarify the pituitary function in patients with subclinical pituitary adenoma haemorrhage (SPAH). DESIGN/PATIENTS: Between January 2006 and December 2012, we retrospectively reviewed 328 consecutive patients who underwent surgery for pituitary adenoma. SPAH was defined as an intratumoral haemorrhage based on both 3 tesla MRI and operative findings, with no clinical symptoms of acute pituitary adenoma apoplexy. The pituitary dysfunction assessed using pre- and postoperative provocative tests was investigated in patients categorized into three groups: nonapoplectic adenoma, adenoma with SPAH and adenoma with clinical apoplexy. MEASUREMENTS: The main outcome measure was the incidence of pituitary dysfunction. RESULTS: The overall incidence of nonapoplectic adenomas, adenomas with SPAH and adenomas with clinical apoplexy was 82·3%, 14·3% and 3·4%, respectively. Clinical pituitary apoplexy frequently occurred in male patients with large nonfunctioning adenomas, causing pituitary dysfunction. Contrastingly, the incidence of SPAH was significantly higher in the patients with prolactinoma (P = 0·0260), including those with relatively small adenomas (P = 0·0007). No medications, such as dopamine agonists or somatostatin analogues, were observed to affect the occurrence of SPAH. No deterioration of the pituitary function was observed in the SPAH patients in comparison with the patients with nonapoplectic adenoma, and the size of the haematoma occupying the pituitary adenoma did not exhibit any relationships with the deterioration of the pituitary function. Furthermore, SPAH caused no deterioration of the pituitary function after a surgery based on the postoperative provocation tests. CONCLUSIONS: Subclinical pituitary adenoma haemorrhage does not cause any added dysfunction in pituitary glands. Signs of haemorrhage in pituitary adenomas do not necessitate immediate tumour decompression surgery, if there are no symptoms of acute haemorrhage.

Pituitary adenomas in childhood and adolescence with a focus on intratumoral hemorrhage.

Pituitary adenomas in childhood and adolescence are relatively rare. In the present study we investigated intratumoral hemorrhage in pituitary adenomas and examined cases of intratumoral hemorrhage using adult patients for comparison. From 1975 to 2012, 38 consecutive patients operated for pituitary adenoma and one patient treated with medication alone, were enrolled in this study. Their ages were less than 18 years old at the initial diagnosis (mean age 15.3 ± 2.9 years). The comparison group consisted of 209 consecutive adult patients (>18 years old). The incidence and characteristics of intratumoral hemorrhage in pituitary adenomas were evaluated, based on magnetic resonance imaging (MRI) findings (28 cases) and on operative findings. The incidence of pituitary adenomas in childhood and adolescence was 38/1,073 (3.5 %) patients operated. Functioning pituitary adenomas (82.1 %) were common and non-functioning pituitary adenomas (17.9 %) were rare. Although no significant difference in tumor size was found and Knosp grade did not differ between young (≤18 years old) and adult (>18 years old) patients, indications of intratumoral hemorrhage on MRI was common in young patients (42.9 %). Based on both MRI and operative findings, intratumoral hemorrhage was significantly more likely to occur in young patients, compared with adult patients.

Transsphenoidal surgical treatment of pituitary adenomas in patients aged 80 years or older.

To know the clinical characteristics of pituitary adenomas in the elderly patients aged 80 years or older who were surgically treated. From 1995 through 2012, 907 patients underwent surgery for the pituitary adenomas at Kagoshima- and Hiroshima University hospitals in Japan. Ten (1.1%) patients were aged 80 years or older. We retrospectively assessed the clinical characteristics including preoperative comorbidities, manifestations, neuroimaging findings, and endocrinologic features of these ten patients. The subjects included eight males and two females. Their ages ranged from 80 to 86 with mean of 83.1 years. Of these, besides one case of growth hormone-producing adenoma, others were clinically nonfunctioning adenoma. Six patients had modest comorbidities such as hypertension, cardiovascular diseases, diabetes mellitus, or chronic kidney dysfunction, and all patients were classified into grade 2-3 on American Society of Anesthesiologists' Physical Status grading. Transsphenoidal surgery was performed in all due to visual disturbance in eight, diabetes mellitus as an intercurrent illness of acromegaly in one, and for the purpose of preventing visual disturbance in one patient who had an adenoma impinging optic chiasm but still had normal visual field. The surgeries provided sufficient decompression of the optic pathways and improved visual disorder in all. In an acromegalic male, his comorbidities considerably improved. No permanent surgical morbidity ensued. More than three axes of anterior pituitary hormones were preoperatively impaired in all, which were rarely recovered. Transsphenoidal surgery is safe and efficient treatment way for patients aged 80 years or older with pituitary adenomas with chiasmatic symptoms when the patients' general condition is well preserved and pituitary hormonal deficiency is adequately replaced.

A case of petrous apex cholesterol granuloma successfully treated with endoscopic endonasal surgery.

A transcranial approach in combination with a transpetrosal setting has been the mainstream of surgical treatment of cholesterol granulomas in the petrous apex. However, endoscopic endonasal surgery has become a choice of treatment for these lesions with recent advancements in surgical techniques and instruments. We report a successful case of cholesterol granuloma managed with endoscopic endonasal surgery. A 45-year-old woman, who had a long-standing history of otitis media, presented with left abducens nerve palsy and discomfort around the left eye. Magnetic resonance (MR) imaging showed a large cystic lesion, suggesting cholesterol granuloma, in the left middle fossa abutting the cavernous sinus and lateral wall of the sphenoid sinus. We chose an endoscopic endonasal approach to drain the contents of the cyst because the lesion protruded into the left sphenoid sinus. The sphenoid sinus was widely opened and the cyst wall was fenestrated with the assistance of an image guidance navigation system. Postoperative MR images confirmed the complete collapse of the cyst. She has been free from symptoms since the operation.

Determination of ultra-trace Te species in open ocean waters based on Mg(OH)2 coprecipitation, anion exchange resin column separation and inductively coupled plasma sector-field mass spectrometry using a 125Te-enriched isotope spike.

We present a method for the determination of ultra-trace Te species (Te(IV) and Te(VI)) in open ocean waters. The proposed method is based on Mg(OH)2 coprecipitation, anion exchange resin column separation and inductively coupled plasma sector-field mass spectrometry (ICPSFMS) using a 125Te-enriched isotope spike. The largest advantage of the method is that the use of the spike allows accurate and precise determination when it combines with either isotope dilution or recovery correction. Tellurium-IV and VI are preconcentrated in a Mg(OH)2 precipitate and separated mutually by an anion exchange resin column. Te(IV) is retained to the column, while Te(VI) passing through the column is recovered by a subsequent column procedure after reduction of Te(VI) to Te(IV). Te(IV) is successfully eluted with a small amount of 0.01 M HCl. The additional merit of using this eluent is elimination of components that result in a memory effect during the measurement of Te(IV). Possible mass spectral interference on Te(IV) can be excluded by adjusting the mass window, and the Te(IV) concentrations determined by this approach agree well with those independently obtained by an oxidation procedure which removes the interference. The accuracy of the proposed method is verified with homemade standard seawater for which the measured concentrations agree well with results calculated from the value of the standard solution. Procedural blanks for Te(IV) and Te(VI) are 1.5 ± 0.9 pg kg-1 (n = 11) and 1.3 ± 0.9 pg kg-1 (n = 11) with corresponding overall detection limits of 3.0 pg kg-1 and 2.8 pg kg-1, respectively. Using the method, we have clarified vertical profiles of Te(IV) and Te(VI) in the subarctic western North Pacific for the first time.

The arginine and GHRP-2 tests as alternatives to the insulin tolerance test for the diagnosis of adult GH deficiency in Japanese patients: a comparison.

The arginine + GHRH test has been established as an alternative to the insulin tolerance test (ITT) for the diagnosis of adult GH deficiency (AGHD). However, the glucagon, arginine, and GH releasing peptide-2 (GHRP-2) test are recommended as alternatives in Japan. The objective of this study was to evaluate the arginine and GHRP-2 tests as alternatives to the ITT for the diagnosis of AGHD in a Japanese population. Three stimulation tests (ITT, arginine test, and GHRP-2 test) were conducted in 71 pre-operative adult patients with pituitary tumors (age, 18-65 years). The peak GH responses to each test were examined. The peak GH responses were significantly lower with the ARG test (median 4.43 µg/L) (p < 0.0001) than with the ITT (median 9.38 µg/L), and the peak GH responses with the GHRP-2 test (median 28.88 µg/L) were higher (p < 0.0001). However, among the AGHD patients, there was no significant difference between the peak GH responses to the ARG test and the ITT. The sensitivities and specificities of the ARG / GHRP-2 tests compared to the ITT for the diagnosis of severe AGHD (peak GH responses to ITT ≤ 1.8 µg/L) were 93.8% / 81.3% and 85.5% / 94.5%, respectively. The arginine and GHRP-2 stimulation tests are acceptable alternatives to the ITT for the diagnosis of AGHD in Japanese patients. The method and criterion for the diagnosis of AGHD should be reconsidered and adjusted to each population.

Postoperative fever specific to neuroendoscopic procedures.

The most common complication of neuroendoscopic surgery is postoperative fever without infection, although the details have not been discussed. The objective of this study was to clarify the clinical features and predicting factors of the postoperative fever following neuroendoscopic procedures. Between March 1998 and March 2013, 83 patients (46 males, 37 females; median age, 14.0 years) who had undergone surgery via the transventricular approach under a neuroendoscopic view were included in this study. A total of 86 neuroendoscopic procedures were performed in 83 patients. The incidence and duration of postoperative fever (≥38.0 and ≥39.0 °C) over the 7 days after surgery were examined. Moreover, the following variables predictive of fever were investigated: age, sex, neuroendoscopic procedure, operative time, and intraoperative irrigation fluid. The incidence of postoperative fever was 65.1 % (≥38.0 °C) and 15.1 % (≥39.0 °C). The median level of the highest fever was 38.6 °C. The fevers developed immediately after surgery and spontaneously disappeared within four postoperative days. Only age was related to postoperative fever (p = 0.032). The postoperative body temperature was negatively correlated with age in all 86 surgeries (p < 0.001, Spearman r = -0.396). In particular, patients under 10 years of age tended to have postoperative fever (p = 0.005). The result of this study demonstrated a peculiar pattern of fever following neuroendoscopic procedures. This type of fever did not cause serious problems; however, special attention should be paid to the high incidence of postoperative fever in patients under 10 years of age.

[A case of solitary fibrous tumor in the sella turcica].

A 64-year-old male presented with an incidental tumor in the sella turcica during a brain medical checkup. Because he lacked any neurological symptoms or signs of pituitary dysfunction, the patient did not undergo surgery. Three years later, visual disturbances developed, including poor eyesight and visual field defects. The response to the growth hormone(GH)releasing peptide-2 demonstrated severe GH deficiency. MRI revealed an enlarged tumor appearing as a mosaic pattern of high and very low intensity on T2-weighted imaging. The region of very low intensity on T2-weighted imaging exhibited enhancement after T1 gadolinium-DTPA administration. The tumor was totally removed via the microscopic trans-sphenoidal approach in combination with endoscopic observation. The hard tumor adhered to the dura of the sella turcica and the medial wall of the left cavernous sinus. Histological verification confirmed a solitary fibrous tumor(SFT). Fourteen months after the operation, MRI revealed no recurrent tumors. SFT infrequently occurs in the sella turcica; however it should be included in the differential diagnosis in cases of enhanced tumors with marked low intensity on T2-weighted imaging.

Post-operative hyponatremia in patients with pituitary adenoma: post-operative management with a uniform treatment protocol.

This study is a retrospective analysis of hyponatremia after transsphenoidal surgery in patients with pituitary adenoma. We evaluated (i) the incidence of post-operative hyponatremia (serum Na levels ≤ 135 mEq/L) and the emergence of hyponatremic symptoms, and assessed (ii) the risk factors under a uniform protocol of i.v. infusion with steroid and electrolyte fluid. We examined 88 consecutive operated patients (female: 60; male: 28) with pituitary adenoma. Apart from reconfirming the effects of the purported risk factors, we focused on the degree of serum Na decline on post-operative hyponatremia. Although remained stable during early post-operative period (4 days after surgery), the serum Na levels subsequently decreased after post-operative day 4 in 81 of 88 cases (92.0%). Of 88 patients, 27 (30.7%) and 9 (10.2%) cases suffered from hyponatremia, and developed hyponatremic symptoms. Interestingly, the degree of serum Na levels decline (from pre-operative levels) indicated a useful independent risk factor for monitoring hyponatremic symptoms (p = 0.006) and the degree of decline tended to be greater in elder patients (> 60 years) (p = 0.0346). Serum Na levels should be monitored from, at least, post-operative day 7 to detect early development of hyponatremia. Special attention and recovery effort should be given to elder patients with marked serum Na level decline after surgery.

Primary and Recurrent Growing Teratoma Syndrome in Central Nervous System Nongerminomatous Germ Cell Tumors: Case Series and Review of the Literature.

BACKGROUND: The term "growing teratoma syndrome (GTS)" has been used as follows: patients with germ cell tumor (GCT) who present with enlarging original/metastatic masses during or after appropriate systemic chemotherapy despite normalized serum markers. In other words, the definition of the term GTS is not fully established. We analyzed and reviewed our case series regarding GTS that developed after the treatment of central nervous system (CNS) nongerminoatous germ cell tumors (NGGCTs). METHODS: Our institutional review board approved this retrospective study. Between 2003 and 2018, we treated 16 patients (16 males; age ranging from 5.4 to 51.9 years, median 13.8) with CNS-NGGCT at our institution. We reviewed those patients and also reviewed the literature about GTS of CNS. We defined primary GTS (p-GTS) as the enlargement of cyst size and/or solid tumor occurred during treatment in the absence of marker elevation, and recurrent GTS (r-GTS) as the enlargement of teratoma after complete response of initial tumors. RESULTS: Among 16 patients with CNS-NGGCT, we surgically confirmed mature/immature teratoma components in 15 patients. Two patients underwent surgical removal of tumor before neoadjuvant therapy, and among the rest 14 patients, 6 developed p-GTS, and 2 patients underwent salvage surgery during chemo-/chemoradiotherapy. Those with histologic diagnosis of immature teratoma during salvage surgery had a shorter interval from the initiation of chemoradiotherapy compared with mature teratoma (P < 0.05). One patient developed r-GTS. In the literature review, most of the p-GTS consisted of enlargement with the multicystic component. Histologic diagnosis of immature teratoma during salvage surgery was observed in earlier stages of chemoradiotherapy (P < 0.05, log-rank test). Previous history of p-GTS might be a risk factor of r-GTS. CONCLUSIONS: The incidence of p-GTS, enlargement of the cystic component during treatment, is not rare. Physicians need to be aware of this important phenomenon.

Physiologic pituitary hyperplasia causing visual disturbance during adolescence.

We report for the first time two cases of physiologic pituitary hyperplasia causing visual disturbance during adolescence. Case 1. A 15-year-old boy visited our department with a pituitary mass lesion on magnetic resonance imaging (MRI) associated with headache and transient bitemporal hemianopsia repeating. A visual field defect became apparent on the bitemporal upper side, and the area of the visual field defect enlarged to hemianopsia. The visual defect usually occurred in relation to exercise and continued for approximately 10 min. MRI showed the mass effect of pituitary hyperplasia to the optic chiasm. At six months later after the initial onset of the symptom, the visual field defect disappeared. Case 2. A 14-year-old girl came to our emergency department with a pituitary mass lesion on MRI associated with acute headache and visual disturbance occurring during exercise. MRI revealed the possibility of pituitary hyperplasia compressing the optic chiasm; however, her clinical course showed pituitary apoplexy. We conducted emergency transsphenoidal surgery to decompress her optic chiasm. The operative findings and histological examinations revealed a normal pituitary gland. Her visual disturbance immediately recovered after the surgery. Physiologic pituitary hyperplasia during adolescence can cause visual disturbance. Surgery should be carefully conducted, given the possibility of physiologic pituitary hyperplasia with visual symptoms.

Proton Magnetic Resonance Spectroscopy Detection of High Lipid Levels and Low Apparent Diffusion Coefficient Is Characteristic of Germinomas.

BACKGROUND: The differentiation of germinoma from other tumors by conventional magnetic resonance imaging (MRI) can be very difficult. The purpose of our study was to determine whether diffusion-weighted imaging (DWI) and single-voxel proton magnetic resonance spectroscopy (1H-MRS) could provide additional useful information for a definitive diagnosis of germinomas. METHODS: Our hospital's Institutional Review Board approved this retrospective study. We reviewed imaging studies of 26 patients with histologically confirmed germinomas who were treated at our hospital between 2003 and 2016. We also studied 25 patients with pineal tumors, which included 14 nongerminomatous germ cell tumors (NGGCTs), 9 pineal parenchymal tumors (PPTs; including 3 pineocytomas, 4 PPTs of intermediate differentiation [PPTID], and 2 pineoblastomas) and 2 meningiomas. Patients underwent conventional MRI and advanced MRI, including DWI and/or 1H-MRS. RESULTS: The germinoma group comprised 24 males and 2 females, ranging in age from 9.1 to 37.7 years (average, 17.5 years; median, 14.6 years). The NGGCT group was all male, ranging in age from 5.4 to 51.9 years (mean, 20.1 years; median, 14.1 years). In the PPT group, patient age ranged from 4.5 to 64.7 years (mean, 29.9 years; median, 30.7 years). High lipid peaks detected on 1H-MRS were observed in 16 of 16 examined germinomas. In contrast, in the pineocytomas, PPTID, pineoblastomas, and meningiomas, lipid peaks were small or absent in 10 of 10 examined tumors. In the NGGCT group, high lipid peaks on 1H-MRS were observed in 11 of 12 examined tumors; however, no tumors showed high intensity on DWI, with all low to high mixed intensity. ADC was statistically lower in the germinoma group compared with the NGGCT group (P = 0.0002). CONCLUSIONS: Lower ADC values and high lipid peaks detected on 1H-MRS are characteristics of germinomas.

Transsphenoidal Posterior Pituitary Lobe Biopsy in Patients with Neurohypophysial Lesions.

OBJECTIVE: The differential diagnosis of neurohypophysial lesions is difficult, and surgical biopsies are indispensable in the histologic diagnosis of some patients. Although pituitary stalk biopsies are uniformly performed, there is a considerable risk that they will result in impaired hormonal secretion. We attempt to clarify the usefulness and safety of posterior pituitary lobe biopsy by transsphenoidal surgery (TSS). METHODS: The cases of 11 consecutive patients who underwent posterior pituitary lobe biopsies by TSS were retrospectively studied. Patients with cystic sellar lesions were excluded. We examined the clinical findings, endocrinologic data, magnetic resonance imaging findings, and histologic diagnoses of the patients. The locations of neurohypophysial lesions and the histologic diagnoses by posterior pituitary lobe biopsies were examined. RESULTS: The major preoperative clinical symptoms were diabetes insipidus (DI) (90.9%), followed by anterior pituitary lobe dysfunction (hypopituitarism) (54.5%). In all the patients, the lesions occupied the pituitary stalk and the posterior pituitary lobe, and the bright spot, which would indicate a normal posterior pituitary gland, disappeared on T1-weighted imaging. The posterior pituitary lobe specimens could be histologically diagnosed in all these cases. DI persisted in 10 patients with preoperative DI after the biopsy, whereas the 1 patient without preoperative DI did not suffer from DI after the biopsy. CONCLUSIONS: A posterior pituitary lobe biopsy by TSS may be an alternative to pituitary stalk biopsy in patients with neurohypophysial lesions.

Preoperative and Postoperative Pituitary Function in Patients with Tuberculum Sellae Meningioma -Based on Pituitary Provocation Tests.

Given the anatomical proximity of tuberculum sellae meningioma (TSM) to the hypothalamo-pituitary system, pituitary function impairments are of great concern. We retrospectively investigated pituitary function changes following surgery in patients with TSM using pituitary provocation tests (PPTs). Thirty-one patients (27 females and 4 males) with TSM underwent initial transcranial surgery (29 patients) or transsphenoidal surgery (two patients); surgeries were performed carefully to avoid injuring the pituitary stalk. In 24 patients, the PPTs were performed via a triple bolus injection with regular insulin, thyrotropin-releasing hormone (TRH), and luteinizing hormone releasing hormone (LH-RH). Seven patients underwent a quadruple test (growth-hormone-releasing factor, corticotrophin-releasing hormone, TRH, and LH-RH). The preoperative and postoperative target hormone levels of the anterior pituitary were normal in 93.5% and 96.8% of patients, respectively. At least one hormonal axis demonstrated impaired PPT responses in two patients (6.5%) preoperatively and in one patient (3.2%) postoperatively. The growth hormone (GH) response was also well preserved. A compromised GH peak level was only observed in one patient (3.2%) preoperatively. Postoperatively, transient diabetes insipidus and transient hyponatremia were observed in four (12.9%) and eight (25.8%) patients, respectively. No patients needed permanent postoperative hormone replacement. The preoperative pituitary function was well preserved in most patients, including those with large tumors pushing against the pituitary stalk considerably or embedded in it. After careful surgery to avoid damaging the pituitary stalk, pituitary function was preserved. However, transient postoperative hyponatremia occurred in 25.8% of patients; thus, surgeons should pay careful attention to this issue.

Pitfalls of Neuroendoscopic Biopsy of Intraventricular Germ Cell Tumors.

OBJECTIVE: A neuroendoscopic biopsy has become common for the diagnosis of ventricular tumors. However, its utility in patients with germ cell tumors (GCTs) has not been well discussed. We examined the usefulness and pitfalls of neuroendoscopic biopsies of intraventricular GCTs at a single institution. METHODS: We retrospectively studied 21 consecutive patients diagnosed with GCTs by a neuroendoscopic biopsy of the ventricular region via the lateral ventricle. We examined the localization of tumors, histologic diagnoses using biopsies, surgical complications, and consistency of the diagnosis at the latest follow-up. RESULTS: Tumor specimens were obtained from a pineal lesion (n = 20), neurohypophysial lesion (n = 5), and lateral ventricular wall lesion (n = 2). In 5 patients, the specimens were obtained from multiple areas. The initial diagnoses were pure germinoma (n = 16), immature teratoma (n = 1), yolk sac tumor (n = 1), and mixed GCT (n = 3). Six of 21 patients needed a second transcranial removal of enhanced residual lesions in the course of the treatment. A discrepancy in the histologic diagnosis between 2 surgeries occurred in 3 patients: All 3 patients had a new diagnosis of teratoma component following transcranial surgery. No postoperative mortality or permanent morbidity related to the neuroendoscopic procedures was noted. CONCLUSION: Neuroendoscopic biopsies are safe and useful for obtaining reliable histologic diagnoses in the management of GCTs. However, for GCTs with mixed histology, biopsies are susceptible to diagnostic errors, especially missing detecting a component of teratoma.