Endoscope-Assisted Microsurgery for Posterior Fossa Skull Base Meningioma Surgery: Technique and Results.

BACKGROUND AND OBJECTIVES: Surgery of posterior fossa meningiomas is extremely challenging even for experienced skull base surgeons because of the close proximity to cranial nerves and tight spaces. Endoscope-assisted surgery for posterior fossa meningiomas can enable a high degree of tumor resection even when using small approaches. This study describes the advantage of endoscope-assisted microneurosurgery in resection of posterior fossa skull base meningiomas and the clinical outcome. METHODS: All endoscope-assisted surgeries for resection of posterior fossa meningiomas performed between 2002 and 2016 in our department were retrospectively analyzed. For data acquisition, the patient files were used. Tumor size and extent of resection were evaluated on pre- and postoperative magnetic resonance imaging. The value of endoscope assistance was assessed according to the intraoperative videos and the surgical notes. Complications and long-term outcomes were evaluated. RESULTS: We identified 39 female and 10 male patients. The mean age of the patients at the time of surgery was 55 years, ranging from 25 to 78 years. The mean follow-up was 93.8 months. A total of 41% of the tumors were large to giant. The retrosigmoid approach was used in most patients (45). A gross total resection could be achieved in 38 patients (78%). In 11 patients (22%), a near total resection was performed. In 27 patients (55%), a hidden residual tumor, which could not been visualized with the operating microscope, was identified with the endoscope. In 6 patients (22.2%), the internal auditory canal was visualized, in 9 patients (33.3%), the Meckel's cave was visualized, and in 5 patients (18.5%), both were visualized under endoscope assistance. In 26 of those patients (96.3%), the residual tumor was resected under endoscopic view. CONCLUSION: Endoscope-assisted surgery for posterior fossa skull base meningiomas enables a high degree of tumor resection, avoids more invasive skull base approaches, and reduces the amount of cerebellar retraction.

Normative body mass-adjusted reference ranges of magnetic resonance imaging signs commonly used in diagnosing idiopathic intracranial hypertension in a healthy standard population.

Patients with chronic daily headaches (CDH) are often a diagnostic challenge and frequently undergo neuroimaging. One common underlying cause of CDH is idiopathic intracranial hypertension (IIH). However, certain neuroimaging abnormalities that suggest IIH, such as optic nerve sheath diameters (ONSD), pituitary gland height, and venous sinus diameter, require interpretation due to the absence of established normative values. Notably, intracranial pressure is known to varies with age, sex and weight, further complicating the determination of objectively abnormal findings within a specific patient group. This study aims to assist clinical neuroradiologists in differentiating neuroimaging results in CDH by providing weight-adjusted normative values for imaging characteristics of IIH. In addition to age and BMI we here assessed 1924 population-based T1-weighted MRI datasets of healthy participants for relevant MRI aspects of IIH. Association to BMI was analyzed using linear/logistic regression controlled for age and stratified for sex. ONSD was 4.3 mm [2.8; 5.9]/4.6 mm [3.6; 5.7] and diameter of transverse sinus was 4.67 mm [1.6; 6.5]/4.45 mm [3.0; 7.9]. Height of pituitary gland was 5.1 mm [2.2;8.1]/4.6 mm [1.9;7.1] for female and male respectively. Values generally varied with BMI with regression slopes spanning 0.0001 to 0.05 and were therefor presented as normative values stratified by BMI. Protrusion of ocular papilla, empty sella and transverse sinus occlusion were rare in total. Our data show an association between BMI and commonly used MRI features for diagnosing IIH. We provide categorized normative BMI values for ONSD, pituitary gland height, and transverse sinus diameter. This distinction helps objectively identify potential IIH indicators compared to regular population norms, enhancing diagnostic accuracy for suspected IIH patients. Notably, optic nerve head protrusion, empty sella, and transverse sinus occlusion are rare in healthy individuals, solidifying their importance as imaging markers regardless of BMI.

Immunophenotyping of Circulating and Intratumoral Myeloid and T Cells in Glioblastoma Patients.

Glioblastoma is the most common and lethal primary brain malignancy that almost inevitably recurs as therapy-refractory cancer. While the success of immune checkpoint blockade (ICB) revealed the immense potential of immune-targeted therapies in several types of cancers outside the central nervous system, it failed to show objective responses in glioblastoma patients as of now. The ability of glioblastoma cells to drive multiple modes of T cell dysfunction while exhibiting low-quality neoepitopes, low-mutational load, and poor antigen priming limits anti-tumor immunity and efficacy of antigen-unspecific immunotherapies such as ICB. An in-depth understanding of the GBM immune landscape is essential to delineate and reprogram such immunosuppressive circuits during disease progression. In this view, the present study aimed to characterize the peripheral and intratumoral immune compartments of 35 glioblastoma patients compared to age- and sex-matched healthy control probands, particularly focusing on exhaustion signatures on myeloid and T cell subsets. Compared to healthy control participants, different immune signatures were already found in the peripheral circulation, partially related to the steroid medication the patients received. Intratumoral CD4+ and CD8+ TEM cells (CD62Llow/CD45ROhigh) revealed a high expression of PD1, which was also increased on intratumoral, pro-tumorigenic macrophages/microglia. Histopathological analysis further identified high PSGL-1 expression levels of the latter, which has recently been linked to increased metastasis in melanoma and colon cancer via P-selectin-mediated platelet activation. Overall, the present study comprises immunophenotyping of a patient cohort to give implications for eligible immunotherapeutic targets in neurooncology in the future.

Pineal cysts without hydrocephalus: microsurgical resection via an infratentorial-supracerebellar approach-surgical strategies, complications, and their avoidance.

Indications for surgery of pineal cysts without ventriculomegaly are still under debate. In view of the limited data for pineal cyst resection in the absence of hydrocephalus, and the potential risk of this approach, we have analyzed our patient cohort focusing on strategies to avoid complications according to our experience in a series of 73 pineal cyst patients. From 2003 to 2015, we reviewed our database retrospectively for all patients operated on a pineal cyst. Furthermore, we prospectively collected patients from 2016 to 2020. In summary, 73 patients with a pineal cyst were treated surgically between 2003 and 2020. All patients were operated on via a microscopic supracerebellar-infratentorial (SCIT) approach. The mean follow-up period was 26.6 months (range: 6-139 months). Seventy-three patients underwent surgery for a pineal cyst. An absence of enlarged ventricles was documented in 62 patients (51 female, 11 male, mean age 28.1 (range 4-59) years). Main presenting symptoms included headache, visual disturbances, dizziness/vertigo, nausea/emesis, and sleep disturbances. Complete cyst resection was achieved in 59/62 patients. Fifty-five of 62 (89%) patients improved after surgery with good or even excellent results according to the Chicago Chiari Outcome Scale, with complete or partial resolution of the leading symptoms. Pineal cysts resection might be an indication in certain patients for surgery even in the absence of ventriculomegaly. The high percentage of postoperative resolution of quality-of-life impairing symptoms in our series seems to justify surgery. Preoperatively, other causes of the leading symptoms have to be excluded.

Purely venous compression in trigeminal neuralgia-can we predict the outcome of surgery.

PURPOSE: Controversies regarding venous compression and trigeminal neuralgia (TN) still exist. The study demonstrates our experience for microvascular decompression (MVD) in TN caused by purely venous compression. The goal was to identify prognostic anatomical or surgical factors that may influence the outcome. METHODS: Between 2004 and 2020, 49 patients were operated with purely venous compression. Average age was 58.4 years. Mean history of TN was 7.8 years. Microsurgical procedures included transposition or separation of the vein, coagulation, and division. Several features have been analyzed with respect to BNI scores. RESULTS: Evaluation on discharge revealed a complete pain relief in 39 (80%), partial improvement in 7 (14%), and no benefit in 3 (6%) patients. Facial hypesthesia was reported by 14 (28.6%) patients. Mean follow-up (FU) was 42.1 months. BNI pain intensity score on FU revealed 71.4% excellent to very good scores (score 1: 32 (65.3%); 2: 3 (6.1%)). BNI facial numbness score 2 could be detected in 13 patients (26.5%) during FU. There was no statistical relationship between immediate pain improvement or BNI pain intensity score on FU with respect to surgical procedure, size of trigeminal cistern, type of venous compression, venous caliber, trigeminal nerve indentation, or neurovascular adherence. BNI facial numbness score was dependent on type of venous compression (p < 0.05). CONCLUSION: We did not find typical anatomical features that could either predict or influence the outcome regarding pain improvement or resolution in any form. Neither classic microvascular decompression (interposition/transposition) nor sacrificing the offending vein made any difference in outcome.

A multivariable prediction model for recovery patterns and time course of symptoms improvement in hemifacial spasm following microvascular decompression.

BACKGROUND: Microvascular decompression (MVD) success rates exceed 90% in hemifacial spasm (HFS). However, postoperative recovery patterns and durations are variable. OBJECTIVE: We aim to study factors that might influence the postoperative patterns and duration needed until final recovery. METHOD: Only patients following de-novo MVD with a minimum follow-up of 6 months were included. Overall trend of recovery was modeled. Patients were grouped according to recognizable clinical recovery patterns. Uni- and multivariable analyses were used to identify the factors affecting allocation to the identified patterns and time needed to final recovery. RESULTS: A total of 323 (92.6%) patients had > 90% symptom improvement, and 269 (77.1%) patients had complete resolution at the last follow-up. The overall trend of recovery showed steep remission within the first 6 months, followed by relapse peaking around 8 months with a second remission ~ 16 months. Five main recovery patterns were identified. Pattern analysis showed that evident proximal indentation of the facial nerve at root exit zone (REZ), males and facial palsy are associated with earlier recovery at multivariable and univariable levels. anterior inferior cerebellar artery (AICA), AICA/vertebral artery compressions and shorter disease durations are related to immediate resolution of the symptoms only on the univariable level. Time analysis showed that proximal indentation (vs. distal indentation), males and facial palsy witnessed significantly earlier recoveries. CONCLUSION: Our main finding is that in contrast to peripheral indentation, proximal indentation of the facial nerve at REZ is associated with earlier recovery. Postoperative facial palsy and AICA compressions are associated with earlier recoveries. We recommend a minimum of 1 year before evaluating the final outcome of MVD for HFS.

Long-term outcome and quality of life after CNS cavernoma resection: eloquent vs. non-eloquent areas.

The aim of this study is to analyze the long-term quality of life after surgery of cavernoma. A monocentric retrospective study was conducted on 69 patients with cavernoma treated microsurgically between 2000 and 2016. The eloquence was adopted from Spetzler-Martin definition. A most recent follow-up was elicited between 2017 and 2019, in which the quality of life (QoL) was evaluated with the Short Form-12 questionnaire (SF12). Forty-one lesions were in eloquent group (EG), 22 in non-eloquent group (NEG), 3 in orbit, and 3 in the spinal cord. Postoperative worsening of the modified Rankin scale (mRS) occurred in 19.5% of cases in EG versus 4.5% in NEG. After a mean follow-up of 6.5 years (SD 4.6), the neurological status was better or unchanged compared to baseline in 85.4% of EG and 100% of NEG. Regarding QoL assessment of 44 patients (EG n = 27, NEG n = 14) attended the last follow-up. Patients after eloquent cavernoma resection reported a non-inferior QoL in most SF12 domains (except for physical role) compared to NEG. However, they reported general health perception inferior to norms, which was affected by the limited physical and emotional roles. At a late follow-up, the surgical morbidity was transient in the NEG and mostly recovered in the EG. The QoL comparison between eloquent and non-eloquent cavernomas created interesting and new data after prolonged follow-up. These results add value for decision-making as well as patient counseling for future encountered cases. Preoperative evaluation of QoL is recommended for future studies to assess QoL dynamics.

Repair of the sellar floor using bioresorbable polydioxanone foils after endoscopic endonasal pituitary surgery.

OBJECTIVE: Postoperative CSF leakage is the most common unwanted sequela of transnasal pituitary surgery. The individual anatomy, the extent of the sellar opening, and the occurrence of an intraoperative CSF leak add to the risk of postoperative rhinorrhea. Despite the current sophistication and recent developments in pituitary surgery, watertight closure of the sellar floor remains a matter of concern. Improvements and additions to the technical armamentarium of sellar reconstruction are therefore still desirable. METHODS: The authors present a closure technique of the sellar floor using a bioresorbable polydioxanone foil, which is placed between the dura and the bony margins of the open sellar floor to keep the intrasellar implants in place and to withstand the pressure arising from the intracranial compartment. RESULTS: The technique was used in a technical case series of 30 patients, and in all patients the floor could be sufficiently reconstructed. CSF flow intraoperatively was documented in 10 cases (33.3%). Postoperative CSF rhinorrhea was detected in one patient (3.3%). No complications could be attributed to the technique or the material during a mean follow-up period of 477 days. The foils can easily be identified on MR images and CT scans and therefore do not affect the postoperative radiological assessment. CONCLUSIONS: The described technique is an easy, inexpensive, and reliable method for sellar floor reconstruction and has a low CSF leakage rate. It is recommended when the risk of a postoperative CSF leak is high and there is still enough bony margin of the sellar floor left that enables a sufficient fixation of the foil.

Primary Leptomeningeal Melanocytic Tumors of the Spine: Report of Two Cases and Review of the Literature.

BACKGROUND: Primary leptomeningeal melanocytic tumors of the central nervous system are rare and, especially in the spine, less frequent compared with other entities. There is no consensus regarding the best care of these tumors. CASE DESCRIPTION: We report 2 cases of primary leptomeningeal melanocytic tumors, 1 primary leptomeningeal melanoma (PLM) and 1 primary leptomeningeal melanocytoma (PLMC) of the upper cervical spine, and emphasize different surgical findings and clinical courses of these patients. A review of the literature according to primary leptomeningeal melanocytic tumors of the spine was done, especially to compare different treatment modalities in the younger history. CONCLUSIONS: Primary melanocytic tumors of the spine are exceedingly rare. Before surgery it is difficult to make a correct diagnosis. Usually an unexpected intraoperative finding with consecutive histopathologic analyses leads to the final diagnosis. An accurate search for melanocytic tumors outside the central nervous system as a primary source is mandatory. PLMC has a better prognosis than PLM. There is no consensus regarding the adjuvant therapy, but patients with PLM should be given radiotherapy, chemotherapy, and immunotherapeutic approaches as immune checkpoint blockade after surgery. Communicating hydrocephalus is highly associated with PLM, but may occur in PLMC as well.

Long-Term Results After Endoscopic Resection of Colloid Cysts.

BACKGROUND: Endoscopic resection of colloid cysts is a widely accepted treatment option instead of microsurgery. However, there is still a debate about a potentially higher rate of incomplete resections and recurrence. OBJECTIVE: The aim of this retrospective study was to evaluate long-term results after endoscopic removal of colloid cysts. METHODS: Twenty patients underwent endoscopic treatment in our department. Eighteen patients agreed to follow-up examinations. In 17 patients, magnetic resonance images were obtained. RESULTS: Total cyst resection was achieved in 16 procedures. In 1 patient, only plexus coagulation and widening of the ipsilateral foramen of Monro were performed. In 3 patients, small remnants of the cyst membrane were left behind. Conversion to microsurgery became necessary in 1 patient. Mild temporary complications occurred in 6 patients. Preoperative symptoms were completely relieved in 16 patients and improved in 2 patients. The average follow-up period was 188 months. In the patient with plexus coagulation, the cyst did not change. Recurrence occurred in 2 of 3 patients with cyst remnants. To date, no cyst remnant or recurrence has caused any symptoms or required surgical treatment. CONCLUSIONS: Our results indicate that endoscopic treatment of colloid cysts is a safe and effective treatment option that provides excellent long-term results. However, we determined that a significant risk for recurrence exists when even small parts of the cyst capsule were left behind. Therefore, we advocate an attempt at total endoscopic cyst resection.

Incidence of and Causes for Ventriculoperitoneal Shunt Failure in Children Younger Than 2 Years: A Systematic Review.

OBJECTIVES: Ventriculoperitoneal (VP) shunting is commonly used to treat pediatric hydrocephalus, but failure rates are high. VP shunt failure in children is mostly caused by infection and/or proximal/distal shunt obstruction. However, to our knowledge, no previous reviews have discussed this topic using only clinical studies when age-related data could be obtained. This systematic review aimed at reevaluating what is already known as the most common causes of shunt failure and to determine the incidence and causes of VP shunt failure during the first 2 years of life as a step to establish solid evidence-based guidelines to avoid VP shunt failure in infants. METHODS: We performed a search using the search terms "Cerebrospinal Fluid Shunts" (Medical Subject Headings [MeSH]) AND failure [All Fields] AND ("humans" [MeSH] AND English [lang] AND "infant" [MeSH]). Only articles that specifically discussed VP shunt complications in children < 2 years were included. RESULTS: We found that the most common causes of VP shunt failure in children < 2 years were shunt obstruction and infection, both observed in a range. CONCLUSION: VP shunt failure is very common in infants, mostly resulting from obstruction and infection. Future studies should focus on methods designed to avoid these complications or on alternative treatments for hydrocephalus.

A radiological and anatomic examination of intralaminar screws in the thoracic spine-a theoretical feasibility study.

BACKGROUND: Failure of pedicle screws and anatomical variations which prevent pedicle screw implantation make the search for an alternative to pedicle screws in thoracic spine surgery necessary. To date, published data have shown that intralaminar screws could be a possible way of fixation. Object of this study is a systematic examination of the feasibility of lamina screws in the whole thoracic spine. METHODS: Fifty females and 50 males (age 20 to 60 years) who underwent a polytrauma CT from 2010 to 2012 were randomly selected. Patients with injury of the thoracic spine, trauma-independent deformity, or dysplasia of the thoracic spine were excluded. A three-dimensional reconstruction of the thoracic spine was performed from the data set. The anatomical data of the lamina were measured under consideration of the potential trajectory of a laminar screw. The caliber of the corresponding pedicle was measured as well. RESULTS: The diameters of the lamina show a decline in superior-inferior direction (0.66 cm in T1 to 0.60 cm in T12 in males, 0.62 to 0.56 cm in females). Diameters of pedicle and lamina show no correlation. Twenty percent of the pedicles have a hypoplasia with a diameter of less than 0.5 cm. However, in these vertebrae, 62.3% of the laminae would be suitable for 0.4-cm lamina screws. Only in 2.75% of the vertebral bodies, there was no possibility for intralaminar or pedicle screws. CONCLUSIONS: This study shows that it is possible to use intralaminar screws in the thoracic spine in most of patients.

Endoscopic Third Ventriculostomy before Posterior Fossa Tumor Surgery in Adult Patients.

OBJECTIVE: Obstructive hydrocephalus in patients with posterior fossa tumors is frequently seen. Treatment options include immediate tumor removal or prior cerebrospinal fluid (CSF) diversion procedures. The necessity and feasibility of an ETV in these situations has not yet been proven in adult patients. METHODS: We retrospectively reviewed our prospectively maintained database for ETVs before surgery of posterior fossa tumors in adults. The primary focus of data analyses was the question of whether the ETV was suitable to treat the acute situation of hydrocephalus without an increased rate of complications due to the special anatomical situation with a posterior fossa tumor. We also analyzed whether any further CSF diverting procedures were necessary. RESULTS: A total of 40 adult patients who underwent an ETV before posterior fossa tumor surgery were analyzed. Overall, 33 patients (82.5%) had clinical signs of hydrocephalus, and all of them improved in their clinical course after ETV. Seven patients (17.5%) did not demonstrate clinical signs of hydrocephalus, but ETV was performed with prophylactic or palliative intent in six patients and one patient, respectively. No complications were observed due to ETV itself. No permanent shunting procedure was necessary in a mean follow-up of 76.5 months. Early additional CSF diverting procedures (redo ETV, external ventricular drain) were performed in five patients (12.5%). CONCLUSION: The present series confirms the feasibility and safety of ETV before posterior fossa tumor surgery in adult patients. If patients had symptomatic hydrocephalus before tumor surgery, an ETV can be performed, followed by early elective tumor surgery. A prophylactic ETV in asymptomatic patients is not advised. Early elective tumor surgery should be performed in these patients.

Endoscopic Biopsy for Intra- and Paraventricular Tumors: Rates of Complications, Mortality, and Tumor Cell Dissemination.

BACKGROUND AND STUDY AIM: Intra- and paraventricular tumors are frequently associated with cerebrospinal fluid (CSF) pathway obstruction. Thus the aim of an endoscopic approach is to restore patency of the CSF pathways and to obtain a tumor biopsy. Because endoscopic tumor biopsy may increase tumor cell dissemination, this study sought to evaluate this risk. PATIENTS, MATERIALS, AND METHODS: Forty-four patients who underwent endoscopic biopsies for ventricular or paraventricular tumors between 1993 and 2011 were included in the study. Charts and images were reviewed retrospectively to evaluate rates of adverse events, mortality, and tumor cell dissemination. Adverse events, mortality, and tumor cell dissemination were evaluated. RESULTS: Postoperative clinical condition improved in 63.0% of patients, remained stable in 30.4%, and worsened in 6.6%. One patient (2.2%) had a postoperative thalamic stroke leading to hemiparesis and hemineglect. No procedure-related deaths occurred. Postoperative tumor cell dissemination was observed in 14.3% of patients available for follow-up. CONCLUSIONS: For patients presenting with occlusive hydrocephalus due to tumors in or adjacent to the ventricular system, endoscopic CSF diversion is the procedure of first choice. Tumor biopsy in the current study did not affect safety or efficacy.

Endoscopic vs Open Decompression of the Ulnar Nerve in Cubital Tunnel Syndrome: A Prospective Randomized Double-Blind Study.

BACKGROUND: Prospective randomized data for comparison of endoscopic and open decompression methods are lacking. OBJECTIVE: To compare the long- and short-term results of endoscopic and open decompression in cubital tunnel syndrome. METHODS: In a prospective randomized double-blind study, 54 patients underwent ulnar nerve decompression for 56 cubital tunnel syndromes from October 2008 to April 2011. All patients presented with typical clinical and neurophysiological findings and underwent preoperative nerve ultrasonography. They were randomized for either endoscopic (n = 29) or open (n = 27) surgery. Both patients and the physician performing the follow-up examinations were blinded. The follow-up took place 3, 6, 12, and 24 months postoperatively. The severity of symptoms was measured by McGowan and Dellon Score, and the clinical outcome by modified Bishop Score. Additionally, the neurophysiological data were evaluated. RESULTS: No differences were found regarding clinical or neurophysiological outcome in both early and late follow-up between both groups. Hematomas were more frequent after endoscopic decompression (P = .05). The most frequent constrictions were found at the flexor carpi ulnaris (FCU) arch and the retrocondylar retinaculum. We found no compressing structures more than 4 cm distal from the sulcus in the endoscopic group. The outcome was classified as "good" or "excellent" in 46 out of 56 patients (82.1%). Eight patients did not improve sufficiently or had a relapse and underwent a second surgery. CONCLUSION: The endoscopic technique showed no additional benefits to open surgery. We could not detect relevant compressions distal to the FCU arch. Therefore, an extensive far distal endoscopic decompression is not routinely required. The open decompression remains the procedure of choice at our institution. ABBREVIATION: Dig, digitFCU, flexor carpi ulnarisNAS, numeric analog scale.

Endoscopic Endonasal Approach for Craniopharyngiomas.

The endoscopic endonasal approach for craniopharyngiomas is increasingly used as an alternative to microsurgical transsphenoidal or transcranial approaches. It is a step forward in treatment, providing improved resection rates and better visual outcome. Especially in retrochiasmatic tumors, this approach provides better lesion access and reduces the degree of manipulations of the optic apparatus. The panoramic view offered by endoscopy and the use of angulated optics allows the removal of lesions extending far into the third ventricle avoiding microsurgical brain splitting. Intensive training is required to perform this surgery. This article summarizes the surgical technique, outcome, and complications.

The small-chamber irrigation technique (SCIT): a simple maneuver for managing intraoperative hemorrhage during endoscopic intraventricular surgery.

BACKGROUND: Acute intraoperative intraventricular hemorrhage is a feared event in endoscopic neurosurgical procedures. OBJECTIVE: To describe the small-chamber irrigation technique (SCIT) for intraoperative endoscopic management of intraventricular hemorrhage. METHODS: The SCIT was used in intraventricular surgery for hydrocephalus, intraventricular tumors requiring biopsy, arachnoid cysts, and colloid cysts. RESULTS: Intraventricular hemorrhage was successfully managed endoscopically with a combination of the SCIT, routine irrigation, and coagulation, allowing for completion of the primary procedures. CONCLUSION: The SCIT is a powerful tool that the neuroendoscopist can use for visualization to achieve hemostasis when performing intraventricular endoscopic surgery.

Is it safe to sacrifice the superior hypophyseal artery in aneurysm clipping? A report of two cases.

Clipping of paraclinoid internal carotid artery aneurysms related to the superior hypophyseal artery (SHA) carries risk of occlusion of this artery when originating distal to the neck of the aneurysm. Sometimes it is inevitable to sacrifice the artery to achieve total aneurysm occlusion. Otherwise a residual aneurysm would remain, which may lead to aneurysm regrowth and subsequent rupture. However, consequences of SHA sacrifice are rarely reported in the literature. In the two presented cases, the SHA was found originating distal to the neck and within the wall of the aneurysm, making the optimal clipping of the aneurysm at the neck unfeasible without trapping of the SHA. Intraoperative indocyanine green (ICG) angiography revealed a retrograde blood flow in the SHA distal to the clip in both patients, indicating some collateral circulation. No endocrinologic deficits were encountered after surgery. The vision was not affected in one patient. In the other patient, bilateral visual field defects occurred, which improved partially in the follow-up 2 months after surgery. The consequences of SHA occlusion are difficult to predict. A large variety of anatomical variations of the vascular anatomy exists. Intraoperative ICG angiography may help to estimate collateral blood flow but is not able to predict visual decline. Although final conclusions cannot be drawn from two patients, it seems that in case of multiplicity of superior hypophyseal complex, sacrifice of one even larger branch is safe. However, visual sequelae have to be taken into consideration when a single SHA has to be sacrificed for total aneurysm clipping.

Endoscopic temporal ventriculocisternostomy: an option for the treatment of trapped temporal horns.

Entrapment of the temporal horn is a rare form of isolated hydrocephalus. Standard treatment has not yet been established for this condition, and only a few cases have been reported in the literature. The authors reviewed their prospectively maintained database to report their experience with endoscopic temporal ventriculocisternostomy. All endoscopic operations performed in the Department of Neurosurgery at Ernst Moritz Arndt University between March 1993 and August 2012 were reviewed, and a retrospective chart review of all patients with temporal ventriculocisternostomy was performed. Four patients were identified (3 children and 1 adult). In 3 patients, the condition developed after tumor resection, and in 1 patient it developed due to postmeningitic multiloculated hydrocephalus. In 2 patients, a recurrent trapped temporal horn developed. Refenestration was successful in one of these patients, and dilation in the trigone area with a subsequent stomy of the septum pellucidum was successful in the other. In 1 patient, postoperative meningitis developed, which was treated with antibiotics. Endoscopic temporal ventriculocisternostomy is an option in the treatment of trapped temporal horns. However, more experience is required to recommend it as the treatment of choice.