[Etiology, Genetic Features and Clinical Presentations in Craniopharyngiomas].

Craniopharyngiomas are among the most challenging intracranial tumors for neurosurgeons. Their management is complicated due to growth patterns such as infiltration into the pituitary stalk, chiasma, and hypothalamus. Therefore, patients may present with various conditions such as endocrine disorders, visual disturbances, or hypothalamic dysfunction in the first medical examination. Moreover, surgical management is challenging because of the high risk of recurrence. Two well-known histological subtypes include adamantinomatous and papillary craniopharyngiomas, and recent advances in genetic analysis have provided significant findings about these subtypes. The adamantinomatous subtype can be distinguished by mutations in CTNNB1, whereas the V600E mutation of the BRAF gene characterizes the papillary subtype. This review describes the etiology, genetic features, and clinical presentations of craniopharyngiomas.

Cyst-to-Mastoid Antrum Diversion as an Alternate Pathway for Management of Small Symptomatic Petrous Apex Cholesterol Granuloma Without Anteromedial Expansion Using an Extradural Middle Fossa Approach: A Technical Case Report.

BACKGROUND AND IMPORTANCE: Cholesterol granuloma (CG) is the most common petrous apex (PA) cystic lesion. Posterolateral expansion of a PA CG (PACG) compresses the internal auditory canal (IAC), leading to vestibulocochlear (VC) and facial nerve dysfunction. Even small, symptomatic PACGs are managed surgically. The preferred strategy is not complete removal, but drainage and aeration. PACG with anteromedial expansion using an endoscopic endonasal approach provides natural drainage into the nasal sinus without risking VC and facial dysfunction. Endoscopic endonasal approach is inappropriate for small PACGs without anteromedial expansion because of potential damage to the petrous internal carotid artery. Small PACGs without anteromedial expansion are managed using extradural middle fossa (EMF) approach, which lacks a natural drainage pathway, thus necessitating an artificial drainage pathway for PACG aeration to prevent recurrence. We introduced EMF approach for CG decompression and cyst-to-mastoid antrum (MA) diversion for managing small, symptomatic PACGs without anteromedial expansion. CLINICAL PRESENTATION: A 48-year-old woman presented with headache, vertigo, tinnitus, and left hemifacial spasm with preserved hearing because of IAC compression caused by a small PACG without anteromedial expansion. Using the EMF approach, the CG and IAC were safely decompressed. Effective and long-standing artificial drainage for CG aeration was established by anterior petrosectomy and silicone tubing from the CG into the MA. Surgery resolved the symptoms, which have not recurred in 3 years. CONCLUSION: Granuloma decompression and cyst-to-MA diversion using silicone tubing using the EMF approach is a safe and effective surgical management for small, symptomatic PACG without anteromedial expansion.

Growth potential of small residual tumors after vestibular schwannoma surgery: comparison between remnants and the natural history of small tumors.

OBJECTIVE: Due to the heterogeneous definitions of tumor regrowth and various tumor volume distributions, the nature of small remnants after vestibular schwannoma (VS) surgery and the appropriate timing of adjuvant stereotactic radiosurgery for these remnants remain unclear. In this study, the growth potential of small remnants (< 1 cm3) after VS surgery was compared with that of treatment-naïve (TN) small VSs. METHODS: This retrospective single-center study included 44 patients with VS remnants following subtotal resection (STR) of a large VS (remnant group) and 75 patients with TN VS (< 1 cm3; TN group). A 20% change in tumor volume over the imaging interval indicated radiographic progression or regression. Tumor progression-free survival (TPFS) rates were estimated using the Kaplan-Meier method. RESULTS: In the remnant group, the mean preoperative tumor volume was 13.8 ± 9.0 cm3 and the mean tumor resection rate was 95% ± 5%. The mean tumor volume at the start of the observation period did not differ significantly between the two groups (remnant vs TN: 0.41 ± 0.29 vs 0.34 ± 0.28 cm3, p = 0.171). The median periods until tumor progression was detected were 15.1 (range 4.9-76.2) months and 44.7 (range 12.6-93.2) months in the TN and remnant groups, respectively. In the remnant group, the TPFS rates were 74% and 70% at 3 and 5 years after the surgery, respectively, compared with 59% and 47% in the TN group. The log-rank test demonstrated a significant difference (p = 0.008) in the TPFS rates between the two groups. Furthermore, 42 patients each from the remnant and TN groups were matched based on tumor volume. TPFS was significantly longer in the remnant group than in the TN group (3-year rates, 77% vs 62%; 5-year rates, 73% vs 51%; p = 0.02). In the remnant group, 18% of the tumor remnants demonstrated regression during follow-up, compared with 9% in the TN group, but this intergroup difference was not significant (p = 0.25). CONCLUSIONS: This study demonstrated that the growth potential of small VS remnants was lower than that of TN tumors. Observing for small remnants may be appropriate after STR of a large VS. Given the risk of tumor regrowth, careful observation using MRI should be mandatory during follow-up.

Proteogenomic landscape and clinical characterization of GH-producing pituitary adenomas/somatotroph pituitary neuroendocrine tumors.

The clinical characteristics of growth hormone (GH)-producing pituitary adenomas/somatotroph pituitary neuroendocrine tumors (GHomas/somatotroph PitNETs) vary across patients. In this study, we aimed to integrate the genetic alterations, protein expression profiles, transcriptomes, and clinical characteristics of GHomas/somatotroph PitNETs to identify molecules associated with acromegaly characteristics. Targeted capture sequencing and copy number analysis of 36 genes and nontargeted proteomics analysis were performed on fresh-frozen samples from 121 sporadic GHomas/somatotroph PitNETs. Targeted capture sequencing revealed GNAS as the only driver gene, as previously reported. Classification by consensus clustering using both RNA sequencing and proteomics revealed many similarities between the proteome and the transcriptome. Gene ontology analysis was performed for differentially expressed proteins between wild-type and mutant GNAS samples identified by nontargeted proteomics and involved in G protein-coupled receptor (GPCR) pathways. The results suggested that GNAS mutations impact endocrinological features in acromegaly through GPCR pathway induction. ATP2A2 and ARID5B correlated with the GH change rate in the octreotide loading test, and WWC3, SERINC1, and ZFAND3 correlated with the tumor volume change rate after somatostatin analog treatment. These results identified a biological connection between GNAS mutations and the clinical and biochemical characteristics of acromegaly, revealing molecules associated with acromegaly that may affect medical treatment efficacy.

Arachnoid cyst alone causes hemifacial spasm: illustrative case.

BACKGROUND: Hemifacial spasm (HFS) due to an arachnoid cyst at the cerebellopontine angle is rare. Here, the authors reported such a case and analyzed the mechanism of facial nerve hyperactivity by reviewing the literature. OBSERVATIONS: A 40-year-old man presented with right HFS for the past 3 years. Preoperative magnetic resonance imaging revealed a right cerebellopontine angle cystic mass with high intensity on T2-weighted images, low intensity on T1-weighted and diffusion-weighted images, and no contrast effects. Cyst excision and decompression of the facial nerve using a lateral suboccipital approach to monitor abnormal muscle response (AMR) resulted in permanent relief. The cyst was histologically compatible with an arachnoid cyst. LESSONS: In the present case, when the cyst was dissected, the AMR disappeared and no offending arteries were detected around the root exit zone. Therefore, the cyst itself was responsible for HFS, for which AMR was useful. Limited cases of HFS due to arachnoid cysts without neurovascular compression have been previously reported. The authors suggested that pulsatile compression by the cyst results in facial nerve hyperactivity and secondary HFS.

ICAM1-Negative Intravascular Large B-Cell Lymphoma of the Pituitary Gland: A Case Report and Literature Review.

OBJECTIVE: Intravascular large B-cell lymphoma (IVLBCL) is a rare and aggressive type of B-cell lymphoma with large cells growing within the lumen of blood vessels. Although previous reports revealed highly variable symptoms resulting from small-vessel occlusion by neoplastic cells in a variety of organs, there are few reports of IVLBCL with pituitary involvement. METHOD: We present a case of IVLBCL with pituitary infiltration from our institution together with a literature review of similar cases to better understand this rare case of IVLBCL involving the pituitary gland. RESULTS: Our case and the pertinent literature demonstrated that IVLBCL with pituitary involvement predominantly occurred in women at a mean age of 64 years, and most of them showed panhypopituitarism that was reversible after standard therapy of rituximab-containing chemotherapy with intrathecal methotrexate. Notably, the pituitary biopsy in our case revealed that atypical large B-cells found within blood vessels and the pituitary gland were negative for intercellular adhesion molecule 1. Intercellular adhesion molecule 1-negative lymphoid cells may have contributed to panhypopituitarism by extravasation into the pituitary tissues, which do not have a blood-brain barrier and receive abundant blood flow. CONCLUSION: IVLBCL of the pituitary gland is a rare lymphoma with nonspecific manifestations and a dismal prognosis. Recognition of the clinicopathological features is necessary for early clinical diagnosis and appropriate treatment.

Predicting Potential of Rapid Tumor Growth in Small to Medium Vestibular Schwannomas on the Basis of Sway Assessed Using Posturography.

OBJECTIVE: The relationship between quantitative posturography results and growth of vestibular schwannomas (VSs) during conservative management has not been studied. We aimed to clarify the relationship between the presence of disequilibrium based on posturographic measurement and VS growth. METHODS: This retrospective, single-center study included 53 patients with VSs (Koos stage I or II) managed conservatively after initial diagnosis. Radiographic progression was considered present if 20% volumetric growth was observed over the imaging interval. Posturography was performed at initial diagnosis, and sway velocity (SV) and sway area were calculated. Tumor growth-free survival was estimated using the Kaplan-Meier method. RESULTS: Mean follow-up period was 2.87 ± 2.58 years, up to tumor growth detection or last follow-up magnetic resonance imaging. Tumor growth incidence was 40.8% and 61.2% at 2 and 5 years, respectively. Cerebellopontine angle extension and SV with eyes open were related to tumor growth. Tumor growth-free survival of patients with cerebellopontine angle extension and patients with intracanalicular tumor at 2 years was 37.3% and 76.4%, respectively. Tumor growth-free survival of patients with SV >2.06 cm/second and patients with SV ≤2.06 cm/second at 2 years was 30.8% and 68.9%, respectively. The Cox hazard model demonstrated a significant risk for future tumor growth with SV >2.06 cm/second (relative risk, 2.475; 95% confidence interval, 1.11-5.37, P = 0.027). CONCLUSIONS: We demonstrated a positive correlation between SV with eyes open and future tumor growth. Posturographic data are objective and quantitative; thus, SV may be a potential predictor of future growth of VSs.

Metastasis of Renal Cell Carcinoma to Spinal Hemangioblastoma in a Patient with von Hippel-Lindau Disease: A Case Report.

von Hippel-Lindau (VHL) disease is characterized by neoplastic and cystic lesions, such as central nervous system (CNS) hemangioblastoma and clear cell renal cell carcinoma (RCC), arising in multiple organs. Here, we report a case of an RCC that metastasized to a spinal hemangioblastoma in a patient diagnosed with VHL disease. This is a unique case study because visceral neoplasms rarely metastasize to the CNS. The patient had undergone posterior fossa surgery for the removal of hemangioblastomas in the right cerebellar hemisphere as a child. He was diagnosed with RCC at the age of 20 years, and he underwent partial nephrectomy at the age of 35 years. The patient underwent surgical removal of a spinal tumor from Th8, which was also diagnosed as a hemangioblastoma at the age of 40. However, the residual spinal tumor rapidly regrew within 1.5 years. A second surgery was performed due to progressive leg motor weakness. The resected tumor from the second surgery had two distinct components between the tumor center and the margin. Immunohistochemistry of CD10, PAX 8, and inhibin A demonstrated the predominant region of the tumor was RCC. Pathological findings confirmed tumor-to-tumor metastasis of the RCC migrating into residual spinal hemangioblastoma. It can be challenging to distinguish hemangioblastoma from RCC in neuroimaging. We suggest that tumor-to-tumor metastasis should be considered as a differential diagnosis if benign tumors grow rapidly, even if the pathological diagnosis does not initially confirm malignancy. The biological mechanisms of RCC migrating into residual hemangioblastoma are discussed.

An aberrant venous channel mimicking the perilabyrinthine cells in the petrous bone of a patient with vestibular schwannoma: illustrative case.

BACKGROUND: Anatomical variations, such as high jugular bulbs and air cell development in the petrosal bone, should be evaluated before surgery. Most bone defects in the internal auditory canal (IAC) posterior wall are observed in the perilabyrinthine cells. An aberrant vascular structure passing through the petrous bone is rare. OBSERVATIONS: A 48-year-old man presented with a right ear hearing disturbance. Magnetic resonance imaging revealed a 23-mm contrast-enhancing mass in the right cerebellopontine angle extending into the IAC, consistent with a right vestibular schwannoma. Preoperative bone window computed tomographic scans showed bone defects in the IAC posterior wall, which ran farther posteroinferiorly in the petrous bone, reaching the medial part of the jugular bulb. The tumor was accessed via a lateral suboccipital approach. There was no other major vein in the cerebellomedullary cistern, except for the vein running from the brain stem to the IAC posterior wall. To avoid complications due to venous congestion, the authors did not drill out the IAC posterior wall or remove the tumor in the IAC. LESSONS: Several aberrant veins in the petrous bone are primitive head sinus remnants. Although rare, their surgical implication is critical in patients with vestibular schwannomas.

Two cases of symptomatic secondary hypophysitis due to Rathke's cleft cysts treated with glucocorticoids: long-term follow-up.

Rathke's cleft cyst (RCC) is a common incidental tumor in the hypothalamic-pituitary region. Some reports have shown that the clinical symptoms and endocrine functions of symptomatic RCCs are temporarily improved by glucocorticoid administration. However, it is still unknown whether glucocorticoid treatment is effective for symptomatic RCCs according to long-term observations. In this study, we describe the long-term clinical outcomes of two cases of glucocorticoid-treated biopsy-proven secondary hypophysitis caused by RCCs. We summarize the symptoms, imaging findings, and endocrine evaluations of two symptomatic RCC patients with concomitant hypophysitis before and after prednisolone treatment. In both evaluated cases, visual impairments and altered endocrine parameters were present due to chiasm and stalk compression; these outcomes improved after shrinkage of RCCs in response to prednisolone administration, and partial recovery of anterior pituitary hormone secretion was observed. However, in both cases, the deficits in anterior pituitary hormone secretion recurred, possibly due to persistent inflammatory infiltration in the RCCs and pituitary glands. After relapse of hypophysitis, anterior hormone secretion did not fully recover. In our cases of secondary hypophysitis caused by RCCs, prednisolone administration had an early effect of cyst shrinkage, followed by partial improvements in clinical symptoms and pituitary functions. However, long-term observation showed that prednisolone treatment did not contribute to complete improvement in anterior pituitary hormone dysfunction.

Transnasal endoscopic resection of Epstein-Barr virus-associated cavernous sinus tumour.

Epstein-Barr virus-associated smooth muscle tumour (EBV-SMT) is a rare disease occurring in immunosuppressed patients, such as those with AIDS, post-transplantation immunodeficiency and congenital immunodeficiency. Intracranial EBV-SMT after solid organ transplantation has been reported. However, intracranial lesions after bone marrow transplantation are extremely rare. We report the case of a 47-year-old man with a history of acute myeloid leukaemia and bone marrow transplantation. He had symptoms of trigeminal neuralgia, and MRI revealed a left cavernous sinus tumour. He started taking oral gabapentin, but his symptoms did not improve. We performed transnasal endoscopic surgery. Postoperative MRI showed complete removal of the cavernous sinus lesion. Pathological examination showed spindle-shaped cells positive for smooth muscle markers and EBV-encoded small RNA in situ hybridisation. EBV-SMT was pathologically diagnosed. His symptoms improved after surgery. No tumour recurrence was noted on follow-up MRI after 15 months without adjuvant radiation or chemotherapy.

The Tethered Effect of Vestibular Schwannoma Tumor Shrinkage Following Stereotactic Radiosurgery in Secondary Trigeminal Neuralgia.

BACKGROUND: Compression of the trigeminal nerve by vessels and tumors causes trigeminal neuralgia. However, a tethering effect, provoking an abnormal root-stretching force, has been previously reported to play a role in trigeminal nerve hyperexcitability. We report 2 patients with vestibular schwannomas treated by stereotactic radiosurgery (SRS) who presented with typical manifestations of trigeminal neuralgia after tumor shrinkage. Furthermore, we discuss the mechanisms of trigeminal neuralgia. CASE DESCRIPTION: Two patients without a history of trigeminal dysfunction, including trigeminal neuralgia, underwent SRS for vestibular schwannomas. Both patients demonstrated tumor shrinkage after transient tumor expansion following SRS. Neither patient presented with facial pain or dysesthesia at the time of peak tumor volume. However, trigeminal neuralgia occurred after tumor shrinkage. One patient underwent surgery, as the neuralgia was refractory to medical treatment; although the trigeminal nerve was adhered and tethered to the tumor, no neurovascular conflict was identified between the tumor and the nerve. We removed the tumor partially, dissecting between the nerve and the tumor, and relieved the tethered effect. Trigeminal neuralgia was relieved without medication after surgery. CONCLUSIONS: The present cases demonstrate a tethered effect of tumor shrinkage after SRS, which was considered to play a role in trigeminal neuralgia. Surgical dissection surrounding the nerve root is effective for medically resistant neuralgia, even if the tumor shrinks. Partial tumor removal is adequate in such cases, as the tumor has been controlled by radiosurgery.

Eighty percent survival rate at 15 years for 1p/19q co-deleted oligodendroglioma treated with upfront chemotherapy irrespective of tumor grade.

INTRODUCTION: Chromosomes 1p/19q co-deletion is a robust molecular marker for the diagnosis of oligodendroglial tumors, and has been included in the 2016 WHO modified classification. Although treatment for oligodendroglioma is controversial, upfront chemotherapy is regarded as one of the treatment option for low-grade tumor. We have treated all the 1p/19q co-deleted oligodendrogliomas, both grades II and III, with upfront chemotherapy without conventional radiotherapy for 20 years. The clinical experience from this trial may be suggestive for understanding of the biological features of oligodendroglioma with 1p/19q co-deletion toward precision medicine. METHODS: This is a long-term retrospective data of the non-selected patients with 1p/19q co-deleted oligodendrogliomas uniformly treated with up-front chemotherapy. Seventy consecutive patients (48 with grade II and 22 with grade III tumors) were included. RESULTS: The median follow-up period was 13 years. The 5-, 10-, and 15-year progression-free survival (PFS) rates were 85.7%, 54.8%, and 31.5%, respectively, and the median PFS was 146 months. In most cases, tumor recurrence was remained local and could be controlled by salvage surgery and/or chemotherapy. The 5-, 10-, and 15-year overall survival (OS) rates were 96.8%, 88.7%, and 80.0%, respectively, and the median OS was not reached. These survival data compared favorably with previous large clinical studies employing radiotherapy. Tumor grades based on World Health Organization classification, extent of surgery, and age affected neither PFS nor OS. Most patients were able to return to their premorbid social life. CONCLUSIONS: The long-term results drawn from 20-years of single institution experience show that the patients with 1p/19q co-deleted oligodendrogliomas can be successfully treated with up-front chemotherapy alone without compromising OS.

Postoperative growth hormone dynamics in clinically nonfunctioning pituitary adenoma.

Growth hormone deficiency (GHD) is an endocrine disorder characterized by insufficient production of growth hormone (GH). Non-functioning pituitary adenoma (NFPA) is one of common causes of GHD. Although most patients with NFPA have transsphenoidal surgery, the time-dependent changes in GH after operation have yet to be investigated. In this study, we analyzed patients with NFPAs that underwent transsphenoidal surgery. Postoperatively, GH secretion was evaluated in response to GH-releasing peptide-2 (GHRP2) infusion. We also investigated how several factors affected GH dynamics. Of 119 patients analyzed, 94 (79.0%) had peak GH levels less than 9.0 ng/mL and were diagnosed with severe GHD (sGHD) immediately after surgery. Of those patients, 27 (28.7%) recovered from sGHD within 1-2 years after surgery. Univariate analyses confirmed that sGHD recovery improved significantly in patients that were younger, had only undergone a single primary surgery, had not had anterior hormone deficiency except GH, and had cystic adenoma or normal insulin-like growth factor-1 (IGF1) standard deviation score (SD-S) levels immediately after surgery. Multivariate analyses confirmed that younger age and absence of hormone replacement therapy significantly predicted sGHD recovery within 1-2 years after surgery. Taken together, our results indicated that postoperative sGHD should be assessed by GHRP2 infusion, regardless of IGF1 SD-S levels. Furthermore, recovery from sGHD occurs more frequently at 1-2 years after surgery especially in younger patients and/or those with GH deficiency alone. These patients, therefore, should be reassessed for GHD by appropriate tests including GHRP2 test at 1-2 years after surgery.

Prednisolone-responsive Postpartum IgG4-related Hypophysitis.

We herein report the case of a 25-year-old woman who presented with severe headache and visual field defects after childbirth. Magnetic resonance imaging revealed marked swelling of the pituitary gland, and an endocrinological examination revealed panhypopituitarism and diabetes insipidus. An immunohistological analysis of a transsphenoidal biopsy sample of the pituitary gland showed the significant accumulation of an immunogloblin G4 (IgG4)-positive population, leading to the diagnosis of IgG4-related hypophysitis. The patient was treated with prednisolone, which markedly reduced the swelling of the pituitary gland, in association with recovery of the pituitary function. This is a rare case of biopsy-proven IgG4-related hypophysitis with a postpartum onset.

Unexpected prominent tension pneumosella five years after endoscopic endonasal transsphenoidal surgery.

Tension pneumosella (TP) is a rare entity reported as the invagination of the sphenoid sinus mucosa into the skull base after endonasal transsphenoidal surgery. Few studies have reported on TP, and in these studies, invagination is confined to either the intrasellar or suprasellar area. We encountered a case of unexpected prominent TP toward the intracranial space 5 years after endoscopic endonasal transsphenoidal surgery (EETS) for a nonfunctioning pituitary adenoma. In addition, we present a hypothesis of the underlying mechanism by a pressure gradient change between the extracranial and intracranial space in TP formation. For repair, a pedicled nasal septal flap was fabricated from the remaining part of the septal mucosa, and a pedicled inferior turbinate flap was created. Moreover, the nasal septal cartilage was used as a rigid support for reconstruction, which was useful for preventing TP recurrence. This is the first report of an unexpected prominent TP after EETS. It is important for otorhinolaryngologists and neurosurgeons to be aware of the possibility of TP following EETS. Laryngoscope, 1798-1801, 2018.

Multihormonal pituitary adenoma concomitant with Pit-1 and Tpit lineage cells causing acromegaly associated with subclinical Cushing's disease: a case report.

BACKGROUND: A functional pituitary adenoma can produce multiple anterior-pituitary hormones, such as growth hormone (GH) -producing adenomas (GHoma) with prolactin or thyrotropin stimulating hormone production in the same lineage. However, it is very rare that acromegaly shows subclinical Cushing's disease (SCD) beyond the lineage. Here we describe the involvement of intratumoral coexistence with 2 types of hormone-producing cells associated with different lineage in acromegaly concomitant with SCD. CASE PRESENTATION: In our study, we performed clinical evaluation of the patient showing acromegaly with SCD. To elucidate the mechanisms of this pathology, we analyzed immunohistochemistry and gene expression of anterior-pituitary hormones and transcriptional factors in the resected pituitary tumor. On immunohistochemical staining, most of the tumor cells were strongly stained for GH antibody, while some cells were strongly positive for adrenocorticotropic hormone (ACTH). Gene expression analysis of a transsphenoidal surgery sample of the pituitary gland revealed that ACTH-related genes, such as POMC, Tpit, and NeuroD1 mRNA, had higher expression in the tumor tissue than the nonfunctional adenoma but lower expression compared to an adenoma of typical Cushing's disease. Further, double-labeling detection methods with a fluorescent stain for ACTH and GH demonstrated the coexistence of ACTH-positive cells (GH-negative) among the GH-positive cells in the tumor. Additionally, Pit-1 expression was reduced in the ACTH-positive cells from tumor tissue primary culture. CONCLUSION: Here we described a case of a pituitary tumor diagnosed with acromegaly associated with SCD. We performed quantitative-expression analyses of transcriptional factors of the tumor tissue and immunohistochemistry analysis of tumor-derived primary culture cells, which suggested that the multihormonal pituitary adenoma concomitant with Pit-1 and Tpit lineage cells caused acromegaly associated with SCD.

A new multilayer reconstruction using nasal septal flap combined with fascia graft dural suturing for high-flow cerebrospinal fluid leak after endoscopic endonasal surgery.

This study aimed to evaluate the usefulness and reliability of a new endoscopic multilayer reconstruction using nasal septal flap (NSF) to prevent high-flow cerebrospinal fluid leak after endoscopic endonasal surgery. This study was a retrospective review on 97 patients who underwent multilayer reconstructions using NSF combined with fascia graft dural suturing after endoscopic endonasal surgery between July 2012 and March 2014. Patients were divided into two groups, third ventricle opening group and nonopening group, based on the presence of a direct connection between the third ventricle and the paranasal sinus after tumor removal. Furthermore, we compared this procedure with our previous reconstruction after resection of craniopharyngioma. Finally, we checked the patients who had postoperative prolonged discomfort of the nasal cavity for over a year. Postoperative cerebrospinal fluid (CSF) leak occurred in three patients (3.1 %): one from the third ventricle opening group and the remaining two from the nonopening group. External lumbar drain was performed after surgery in only seven patients (7.2 %). The incidence of postoperative CSF leak was similar in both groups, whereas the rate of craniopharyngioma in the third ventricle opening group was significantly higher. The incidence of postoperative CSF leak after resection of craniopharyngioma was not statistically significant but obviously higher in the previous group (12.2 %) compared with that in the present group (2.3 %). Twelve patients (12.4 %) had postoperative nasal discomfort of the nasal cavity for over a year. Multilayer reconstruction using NSF combined with fascia graft dural suturing is a more reliable method for preventing postoperative high-flow CSF leakage after endoscopic endonasal surgery even if there is a direct connection between the third ventricle and the paranasal sinus. However, we should pay close attention especially to prolonged discomfort of the nasal cavity after harvesting NSF.

Life-Threatening Intracranial Hypotension after Skull Base Surgery with Lumbar Drainage.

Although lumbar drainage (LD) is widely used in skull base surgery (SBS), no cases with intracranial hypotension (IH) following LD-assisted SBS have been reported, and skull base surgeons lack awareness of this potentially life-threatening condition. We report two cases of IH after LD-assisted SBS, a spheno-orbital meningioma and an osteosarcoma in the orbit. Despite a minimal amount of cerebrospinal fluid (CSF) drainage and early LD removal, severe postural headache and even a deteriorating consciousness level were observed in the early postoperative course. Neuroimages demonstrated epidural fluid collections, severe midline shift, and tonsillar sag compatible with IH. Epidural blood patch (EBP) immediately and completely reversed the clinical and radiologic findings in both patients. IH should be included in the differential diagnosis of postural headache after LD-assisted SBS that can be managed successfully with EBP. Persistent leakage of CSF at the LD-inserted site leads to IH. Broad dural dissection and wide removal of bony structure may be involved in the midline shift. EBP should be performed soon after conservative management fails. Further reports will determine the risk factors for IH development following LD-assisted SBS.