Risk factors for postoperative seizures in patients with chronic subdural haematomas.

Postoperative seizures are a frequently occurring yet not well-understood complication in patients undergoing surgical treatment of chronic subdural haematomas (cSDHs). Therefore, we investigated surgical and non-surgical risk factors that are commonly considered causal in provoking epileptic seizures, paying special attention to the intracranial course of the subdural drain (SDD) and the configuration of the haematoma. Data of patients with a cSDH, that were treated at our neurosurgical department between 2008 and 2014 were analysed. Patients suffering from severe pre-existing conditions and those who have been treated conservatively were excluded. Epidemiologic data as well as relevant clinical data were collected. Pre- and postoperative CT scans were analysed regarding morpho- and volumetric parameters. In order to objectify the influence of the SDD, its intracranial course and localisation (entering angle as well as the angle between drain and brain surface) were measured. For statistical analysis, univariate and multiple logistic regression models as well as Fisher's exact test were used. Two hundred eleven consecutive patients have been included. Mean age was 75.6 years, and 69% were male. Nineteen (9%) patients suffered from postsurgical seizures. Membranes within the haematoma were present in 81.5%. Pre- to postoperative haematoma reduction was significant (mean of difference - 12.76 mm/ - 9.47 mm in coronal/axial CT planes, p = 0.001/ < 0.001). In 77.9%, SDD showed cortical contact with eloquent regions and had an unfavourable course in 30 cases (14.2%). Surgical complications consisted of cortical bleeding in 2.5%, fresh subdural haematoma in 33.5% and wound infections in 1.4% of patients. Neither in univariate nor in multiple regression analyses any of the following independent variates was significantly correlated with postsurgical seizures: pre-existing epilepsy, alcohol abuse, right-sided haematomas, localization and thickness of haematoma, presence of septations, SDD-localization and to-brain angle, subdural air, and electrolyte levels. Instead, in multiple regression analyses, we found the risk of postsurgical seizures to be significantly correlated and increased with left-sided cSDH treated via craniotomy (p = 0.03) and an unfavourable course of the SDD in left-sided cSDH (p = 0.033). Burr hole trepanation should be preferred over craniotomy and care must be taken when placing a SDD to avoid irritating cortical tissue. The configuration of the haematoma does not appear to affect the postoperative seizure rate.

Microglia inflict delayed brain injury after subarachnoid hemorrhage.

Inflammatory changes have been postulated to contribute to secondary brain injury after aneurysmal subarachnoid hemorrhage (SAH). In human specimens after SAH as well as in experimental SAH using mice, we show an intracerebral accumulation of inflammatory cells between days 4 and 28 after the bleeding. Using bone marrow chimeric mice allowing tracing of all peripherally derived immune cells, we confirm a truly CNS-intrinsic, microglial origin of these immune cells, exhibiting an inflammatory state, and rule out invasion of myeloid cells from the periphery into the brain. Furthermore, we detect secondary neuro-axonal injury throughout the time course of SAH. Since neuronal cell death and microglia accumulation follow a similar time course, we addressed whether the occurrence of activated microglia and neuro-axonal injury upon SAH are causally linked by depleting microglia in vivo. Given that the amount of neuronal cell death was significantly reduced after microglia depletion, we conclude that microglia accumulation inflicts secondary brain injury after SAH.

Necrotizing infundibulo-hypophysitis: an entity too rare to be true?

We report a young woman with sudden and severe retroorbital headache, neck pain, and a large sellar mass extending to the suprasellar cistern. A presumptive diagnosis of non-secreting pituitary macroadenoma undergoing apoplexy was made and transphenoidal surgery performed. Histopathology revealed mononuclear infiltration and marked non-hemorrhagic necrosis of the anterior pituitary consistent with a diagnosis of necrotizing infundibulo-hypophysitis. The possible pathogenesis of this rare variant of hypophysitis is discussed.

Pituitary and systemic autoimmunity in a case of intrasellar germinoma.

Germinomas arising in the sella turcica are difficult to differentiate from autoimmune hypophysitis because of similar clinical and pathological features. This differentiation, nevertheless, is critical for patient care due to different treatments of the two diseases. We report the case of an 11-year-old girl who presented with diabetes insipidus and growth retardation, and was found to have an intra- and supra-sellar mass. Initial examination of the pituitary biopsy showed diffuse lymphocytic infiltration of the adenohypophysis and absent placental alkaline phosphatase expression, leading to a diagnosis of hypophysitis and glucocorticoid treatment. Because of the lack of clinical and radiological response, the pituitary specimen was re-examined, revealing this time the presence of scattered c-kit and Oct4 positive germinoma cells. The revised diagnosis prompted the initiation of radiotherapy, which induced disappearance of the pituitary mass. Immunological studies showed that the patient's serum recognized antigens expressed by the patient's own germinoma cells, as well as pituitary antigens like growth hormone and systemic antigens like the Sjögren syndrome antigen B and alpha-enolase. The study first reports the presence of pituitary and systemic antibodies in a patient with intrasellar germinoma, and reminds us that diffuse lymphocytic infiltration of the pituitary gland and pituitary antibodies does not always indicate a diagnosis of autoimmune hypophysitis.

Evaluation of efficacy and biocompatibility of a novel semisynthetic collagen matrix as a dural onlay graft in a large animal model.

BACKGROUND: Semisynthetic collagen matrices are promising duraplasty grafts with low risk of cerebrospinal fluid (CSF) fistulas, good tissue integration and minor foreign body reaction. The present study investigates the efficacy and biocompatibility of a novel semisynthetic bilayered collagen matrix (BCM, B. Braun Aesculap) as dural onlay graft for duraplasty. METHODS: Thirty-four pigs underwent osteoclastic trepanation, excision of the dura, and placement of a cortical defect, followed by duraplasty using BCM, Suturable DuraGen™ (Integra Neuroscience), or periosteum. CSF tightness and intraoperative handling of the grafts were evaluated. Pigs were sacrificed after 1 and 6 months for histological analysis. FINDINGS: BCM and DuraGen™ showed superior handling than periosteum with a trend for better adhesion to dura and CSF tightness for BCM. Periosteum, which was sutured unlike the synthetic grafts, had the highest intraoperative CSF tightness. Duraplasty time with periosteum was significantly higher (14.4 ± 2.7 min) compared with BCM (2.8 ± 0.8 min) or DuraGen™ (3.0 ± 0.5 min). Tissue integration by fibroblast infiltration was observed after 1 month for all devices. More adhesions between graft and cortex were observed with DuraGen™ compared with BCM and periosteum. No relevant adhesions between leptomeninges and BCM were observed and all devices showed comparable lymphocytic reaction of the brain. All devices were completely integrated after 6 months. BCM and DuraGen™ showed a trend for an enhanced lymphocytic reaction of the brain parenchyma compared with periosteum. Implant rejection was not observed. CONCLUSION: Semisythetic collagen matrices are an attractive alternative in duraplasty due to their easy handling, lower surgical time, and high biocompatibility.

CNS tumor 22 years after spinal neuroblastoma IV: diagnostic dilemma between recurrence and secondary malignancy.

We present the very unusual case of a young woman suffering from a brain tumor 22 years after a stage IV spinal neuroblastoma as an infant, demonstrating the difficulties of differentiating late neuroblastoma relapse from secondary supratentorial primitive neuroectodermal tumor (sPNET). Lacking specific immunohistochemical features, the first cerebral tumor at the age of 21 was regarded as sPNET, and we pursued a therapeutic approach consisting of neurosurgical resection as well as irradiation and high-dose alkylator-based chemotherapy according to the HIT2000 protocol. Two years later the patient suffered from a diffusely infiltrating local recurrence, changing its imaging appearance as well as its immunohistochemical characteristics, now revealing disseminated positivity for neuron-specific enolase and neural cell adhesion molecule. Moreover, the lack of PNET-specific translocations (EWS/FLI1 gene fusion) in both brain tumors as well as the development of hepatic metastases was more compatible with the diagnosis of a very late relapse 22 years after initial stage IV spinal neuroblastoma.

Oculo-Auriculo-Vertebral Dysplasia With Craniocervical Instability and Occult Tethered Cord Syndrome. An Addition to the Spectrum? First Case Report and Review of the Literature.

Oculo-auriculo-vertebral spectrum (OAVS) is an uncommon congenital disorder of abnormal development of the first and second pharyngeal arches. This spectrum is characterized by craniofacial microsomia, epibulbar dermoids, ear abnormalities, renal and cardiac defects, and a wide range of vertebral segmentation and formation disorders. Frequently, the cervicothoracic spine is involved. Only recently, the morbidity attributed to the spinal abnormalities has gained attention. Strategy and timing of spine surgery has become increasingly important in patients with OAVS. Here, we report a case of OAVS with characteristic vertebral cervical and thoracic involvement and its sequelae requiring multiple spinal procedures, further complexed by an unprecedented occult tethered cord syndrome, which was successfully treated by surgical detethering. In this context, the recent literature on spinal anomalies is reviewed.

Information needs of patients in spine surgery: development of a question prompt list to guide informed consent consultations.

BACKGROUND CONTEXT: Informed consent is mandatory before surgery and fundamental in the physician-patient interaction. However, communication is sometimes suboptimal. PURPOSE: The objective was to develop a question prompt list (QPL) for patients undergoing spine surgery (spinal neurosurgery-QPL, "SN-QPL") to encourage them to acquire information during the informed consent consultation (ICC) and assess patients' information needs. STUDY DESIGN/SETTING: We conducted a prospective uncontrolled single center study in order to develop a QPL for patients undergoing spine surgery. PATIENT SAMPLE: Patients inclusion criteria were as follows: (1) planned spinal surgery, (2) age 18 to 80 years, (3) legal capacity, (4) ability to understand and respond to questionnaires, and (5) informed consent. OUTCOME MEASURES: We applied the following self-report measures: the developed preliminary QPL with regard to surgery topics and assessment of patients' information needs. METHODS: First, we performed a literature review, patient interviews, and two expert rounds. Subsequently, we validated a preliminary SN-QPL including 37 items before and after ICC with regard to importance of items and fulfillment of information needs in 118 patients. A principal component analysis followed by varimax rotation revealed the final SN-QPL. RESULTS: For the final version of the SN-QPL, 27 items with following four reliable subscales were derived with satisfactory internal consistency: (1) scale SN-QPL-C, "complications and possible postoperative deficits" (n  =  8 items, Cronbach α = 0.88); (2) scale SN-QPL-P, "prognosis and follow-up" (n = 8 items, Cronbach α = 0.86); (3) scale SN-QPL-I, "preoperative inpatient stay and organizational issues" (n = 5 items, Cronbach α = 0.75); and (4) scale SN-QPL-S: "safety of the surgical procedure" (with n = 6 items, Cronbach α = 0.84). The most unmet information needs were found in SN-QPL-P. The item with the greatest unmet information needs was "How much professional experience does my surgeon have?" CONCLUSIONS: Our SN-QPL was well-accepted and perceived as helpful by patients awaiting spinal surgeries. It seems to address meaningful items and questions. It could therefore be useful in optimizing pre- and postoperative satisfaction. Further, our study identified many unaddressed questions warranting communication interventions.

Autoimmune hypophysitis of SJL mice: clinical insights from a new animal model.

Autoimmune hypophysitis (AH) is a rare but increasingly recognized disease of the pituitary gland. Its autoantigens are unknown, and the management is difficult because it is often misdiagnosed as a nonsecreting adenoma. By immunizing female SJL/J mice with mouse pituitary extracts, we established a new mouse model of experimental AH. Immunized mice developed severe lymphocytic infiltration in the anterior pituitary that closely mimicked the human pathology. In the early phase of experimental AH, the pituitary enlarged, consistent with the compression symptoms reported by hypophysitis patients at presentation. In the florid phase, adrenal insufficiency and pituitary antibodies developed, in strong correlation with the pituitary pathology. In the late phase, hypothyroidism ensued, and the pituitary gland became atrophic. Using immune sera as probes in a two-dimensional immunoblotting screen followed by mass spectrometry, we identified several proteins that could function as pituitary autoantigens. These findings provide new insights into the pathogenesis of AH, and establish a platform for developing novel diagnostic biomarkers and therapeutics.

Novel autoantigens in autoimmune hypophysitis.

BACKGROUND: Pituitary autoantibodies are found in autoimmune hypophysitis and other conditions. They are a marker of pituitary autoimmunity but currently have limited clinical value. The methods used for their detection lack adequate sensitivity and specificity, mainly because the pathogenic pituitary autoantigen(s) are not known and therefore antigen-based immunoassays have not been developed. OBJECTIVES: This study aimed to identify novel pituitary autoantigens using sera as probes in proteomic assays. We also compared immunoblotting and immunofluorescence methods for their accuracy in diagnosing autoimmune hypophysitis. STUDY DESIGN AND SUBJECTS: Twenty-eight sera from autoimmune hypophysitis cases (14 histologically proven and 14 clinically suspected) were compared to 98 sera from controls, which included 14 patients with pituitary adenomas, 48 with autoimmune thyroiditis (15 Graves' disease and 33 Hashimoto's thyroiditis) and 36 healthy subjects. METHODS: All sera were tested against human pituitary cytosolic proteins separated by one-dimensional (1D) gel electrophoresis. The band recognition was analysed statistically to detect molecular weight regions preferentially recognized by hypophysitis sera. 2D gel immunoblotting and mass spectrometry were then used to sequence the protein spots of interest. Sera were also tested by immunofluorescence for their recognition of Macaca mulatta pituitary sections. RESULTS: A single region in the 25-27-kDa range was recognized more often by hypophysitis cases than healthy subjects (P = 0.004) or patients with pituitary adenomas (P = 0.044). This region contained two novel candidate autoantigens: chromosome 14 open reading frame 166 (C14orf166) and chorionic somatomammotrophin. Immunoblotting positivity for the 25-27-kDa region yielded greater sensitivity (64%vs. 57%) and specificity (86%vs. 76%) than immunofluorescence in predicting histologically proven hypophysitis, although the performance was still inadequate to make immunoblotting a clinically useful test. CONCLUSION: The study reports two novel proteins that could act as autoantigens in autoimmune hypophysitis. Further studies are needed to validate their pathogenic role and diagnostic utility.

Correlation of chromosomal imbalances by comparative genomic hybridization and expression of EGFR, PTEN, p53, and MIB-1 in diffuse gliomas.

The histological subclassification of gliomas is increasingly assisted by the underlying molecular genetics which has major importance in guiding clinical management of the disease. However, the assessment of several molecular events for improving clinical care remains a challenge. Herein, we report on comparative genomic hybridization (CGH) and immunohistochemical (IHC) assessment of EGFR, PTEN, p53, and MIB-1 expression in 13 oligodendrogliomas (10 WHO grade II, 3 WHO grade III), one oligoastrocytoma (WHO grade III) and 23 high-grade astrocytomas (3 WHO grade III, 20 glioblastoma multiforme). The most frequent imbalances in oligodendroglial tumors including the oligoastrocytic case were, in decreasing order of frequency, +7q, -1p, and -4q and in astrocytomas +7q, -10q, +7p, -9p, -10p, +20q, and +20p. Some individual imbalances were associated with increasing numbers of chromosomal changes, that were +7q in both oligodendrogliomas and astrocytomas, and -9p, -10q, +20p, and +20q in astrocytomas. The markers p53 and MIB-1 were significantly higher expressed in astrocytomas than in oligodendrogliomas and expression levels of p53 and EGFR were inversely associated within the astrocytic group. In addition, p53 overexpression correlated positively with +7q and negatively with -1p in the oligodendroglial group whereas EGFR overexpression correlated positively with -1p in the oligodendroglial and positively with +7p and -10p in the astrocytic group. Short overall survival was significantly associated with +7p and -10q in astrocytomas. Collectively, these results contribute to the increasing clinical relevance of assessing tumor biological markers in gliomas.

Spontaneous adrenal hemorrhage: a little-known complication of intracranial tumor surgery. Case report.

Nontraumatic adrenal hemorrhage in adults is uncommon and unexpected in the context of intracranial surgery. The authors report on a patient in whom hemodynamically relevant retroperitoneal bleeding developed within hours after an otherwise uneventful operation for a falcine meningioma. In this brief report they seek to draw attention to this rare but life-threatening complication, because rapid diagnosis can be life-saving.

Navigation and Image Injection for Control of Bone Removal and Osteotomy Planes in Spine Surgery.

BACKGROUND AND IMPORTANCE: In contrast to cranial interventions, neuronavigation in spinal surgery is used in few applications, not tapping into its full technological potential. We have developed a method to preoperatively create virtual resection planes and volumes for spinal osteotomies and export 3-D operation plans to a navigation system controlling intraoperative visualization using a surgical microscope's head-up display. The method was developed using a Sawbone ® model of the lumbar spine, demonstrating feasibility with high precision. Computer tomographic and magnetic resonance image data were imported into Amira ® , a 3-D visualization software. Resection planes were positioned, and resection volumes representing intraoperative bone removal were defined. Fused to the original Digital Imaging and Communications in Medicine data, the osteotomy planes were exported to the cranial version of a Brainlab ® navigation system. A navigated surgical microscope with video connection to the navigation system allowed intraoperative image injection to visualize the preplanned resection planes. CLINICAL PRESENTATION: The workflow was applied to a patient presenting with a congenital hemivertebra of the thoracolumbar spine. Dorsal instrumentation with pedicle screws and rods was followed by resection of the deformed vertebra guided by the in-view image injection of the preplanned resection planes into the optical path of a surgical microscope. Postoperatively, the patient showed no neurological deficits, and the spine was found to be restored in near physiological posture. CONCLUSION: The intraoperative visualization of resection planes in a microscope's head-up display was found to assist the surgeon during the resection of a complex-shaped bone wedge and may help to further increase accuracy and patient safety.

Alternative radiation-free registration technique for image-guided pedicle screw placement in deformed cervico-thoracic segments.

BACKGROUND: Image-guided pedicle screw placement in the cervico-thoracic region is a commonly applied technique. In some patients with deformed cervico-thoracic segments, conventional or 3D fluoroscopy based registration of image-guidance might be difficult or impossible because of the anatomic/pathological conditions. Landmark based registration has been used as an alternative, mostly using separate registration of each vertebra. We here investigated a routine for landmark based registration of rigid spinal segments as single objects, using cranial image-guidance software. METHODS: Landmark based registration of image-guidance was performed using cranial navigation software. After surgical exposure of the spinous processes, lamina and facet joints and fixation of a reference marker array, up to 26 predefined landmarks were acquired using a pointer. All pedicle screws were implanted using image guidance alone. Following image-guided screw placement all patients underwent postoperative CT scanning. Screw positions as well as intraoperative and clinical parameters were retrospectively analyzed. RESULTS: Thirteen patients received 73 pedicle screws at levels C6 to Th8. Registration of spinal segments, using the cranial image-guidance succeeded in all cases. Pedicle perforations were observed in 11.0%, severe perforations of >2 mm occurred in 5.4%. One patient developed a transient C8 syndrome and had to be revised for deviation of the C7 pedicle screw. No other pedicle screw-related complications were observed. CONCLUSIONS: In selected patients suffering from pathologies of the cervico-thoracic region, which impair intraoperative fluoroscopy or 3D C-arm imaging, landmark based registration of image-guidance using cranial software is a feasible, radiation-saving and a safe alternative.

Three-dimensional Cross-Platform Planning for Complex Spinal Procedures: A New Method Adaptive to Different Navigation Systems.

STUDY DESIGN: A feasibility study. OBJECTIVE: To develop a method based on the DICOM standard which transfers complex 3-dimensional (3D) trajectories and objects from external planning software to any navigation system for planning and intraoperative guidance of complex spinal procedures. SUMMARY OF BACKGROUND DATA: There have been many reports about navigation systems with embedded planning solutions but only few on how to transfer planning data generated in external software. MATERIALS AND METHODS: Patients computerized tomography and/or magnetic resonance volume data sets of the affected spinal segments were imported to Amira software, reconstructed to 3D images and fused with magnetic resonance data for soft-tissue visualization, resulting in a virtual patient model. Objects needed for surgical plans or surgical procedures such as trajectories, implants or surgical instruments were either digitally constructed or computerized tomography scanned and virtually positioned within the 3D model as required. As crucial step of this method these objects were fused with the patient's original diagnostic image data, resulting in a single DICOM sequence, containing all preplanned information necessary for the operation. By this step it was possible to import complex surgical plans into any navigation system. RESULTS: We applied this method not only to intraoperatively adjustable implants and objects under experimental settings, but also planned and successfully performed surgical procedures, such as the percutaneous lateral approach to the lumbar spine following preplanned trajectories and a thoracic tumor resection including intervertebral body replacement using an optical navigation system. To demonstrate the versatility and compatibility of the method with an entirely different navigation system, virtually preplanned lumbar transpedicular screw placement was performed with a robotic guidance system. CONCLUSIONS: The presented method not only allows virtual planning of complex surgical procedures, but to export objects and surgical plans to any navigation or guidance system able to read DICOM data sets, expanding the possibilities of embedded planning software.

A novel minimally invasive, dorsolateral, tubular partial odontoidectomy and autologous bone augmentation to treat dens pseudarthrosis: cadaveric, 3D virtual simulation study and technical report.

OBJECTIVE The goal of this study was to demonstrate the clinical and technical nuances of a minimally invasive, dorsolateral, tubular approach for partial odontoidectomy, autologous bone augmentation, and temporary C1-2 fixation to treat dens pseudarthrosis. METHODS A cadaveric feasibility study, a 3D virtual reality reconstruction study, and the subsequent application of this approach in 2 clinical cases are reported. Eight procedures were completed in 4 human cadavers. A minimally invasive, dorsolateral, tubular approach for odontoidectomy was performed with the aid of a tubular retraction system, using a posterolateral incision and an oblique approach angle. Fluoroscopy and postprocedural CT, using 3D volumetric averaging software, were used to evaluate the degree of bone removal of C1-2 lateral masses and the C-2 pars interarticularis. Two clinical cases were treated using the approach: a 23-year-old patient with an odontoid fracture and pseudarthrosis, and a 35-year-old patient with a history of failed conservative treatment for odontoid fracture. RESULTS At 8 cadaveric levels, the mean volumetric bone removal of the C1-2 lateral masses on 1 side was 3% ± 1%, and the mean resection of the pars interarticularis on 1 side was 2% ± 1%. The median angulation of the trajectory was 50°, and the median distance from the midline of the incision entry point on the skin surface was 67 mm. The authors measured the diameter of the working channel in relation to head positioning and assessed a greater working corridor of 12 ± 4 mm in 20° inclination, 15° contralateral rotation, and 5° lateral flexion to the contralateral side. There were no violations of the dura. The reliability of C-2 pedicle screws and C-1 lateral mass screws was 94% (15 of 16 screws) with a single lateral breach. The patients treated experienced excellent clinical outcomes. CONCLUSIONS A minimally invasive, dorsolateral, tubular odontoidectomy and autologous bone augmentation combined with C1-2 instrumentation has the ability to provide excellent 1-stage management of an odontoid pseudarthrosis. The procedure can be completed safely and successfully with minimal blood loss and little associated morbidity. This approach has the potential to provide not only a less invasive approach but also a function-preserving option to treat complex C1-2 anterior disease.

In Situ Activation of Pituitary-Infiltrating T Lymphocytes in Autoimmune Hypophysitis.

Autoimmune hypophysitis (AH) is a chronic inflammatory disease characterized by infiltration of T and B lymphocytes in the pituitary gland. The mechanisms through which infiltrating lymphocytes cause disease remain unknown. Using a mouse model of AH we assessed whether T lymphocytes undergo activation in the pituitary gland. Infiltrating T cells co-localized with dendritic cells in the pituitary and produced increased levels of interferon-γ and interleukin-17 upon stimulation in vitro. Assessing proliferation of CD3- and B220-postive lymphocytes by double immunohistochemistry (PCNA-staining) and flow cytometry (BrdU incorporation) revealed that a discrete proportion of infiltrating T cells and B cells underwent proliferation within the pituitary parenchyma. This proliferation persisted into the late disease stage (day 56 post-immunization), indicating the presence of a continuous generation of autoreactive T and B cells within the pituitary gland. T cell proliferation in the pituitary was confirmed in patients affected by autoimmune hypophysitis. In conclusion, we show that pituitary-infiltrating lymphocytes proliferate in situ during AH, providing a previously unknown pathogenic mechanism and new avenues for treatment.

Primary hypophysitis: clinical-pathological correlations.

OBJECTIVE: Primary hypophysitis comprises of three distinct histomorphological entities: lymphocytic, granulomatous and xanthomatous. Clinical features of the three subtypes for diagnostic and treatment strategies have yet not been well characterized. METHODS: Endocrine function, visual fields and acuity as well as magnetic resonance imaging characteristics were assessed before and after transphenoidal surgery in the largest series of 31 patients with primary hypophysitis (21 lymphocytic, 6 granulomatous, and 4 xanthomatous cases). RESULTS: Only lymphocytic hypophysitis occurred during pregnancy (30%) and was associated with other autoimmune diseases (24%). Visual fields and acuity abnormalities were not seen in xanthomatous hypophysitis. Lymphocytic and granulomatous hypophysitis most often resulted in severe dysfunction of the adrenal, gonadal and thyroidal axes as well as diabetes insipidus. For patients presenting with xanthomatous hypophysitis most often, mild anterior pituitary axis failure was documented and posterior pituitary involvement was hardly found. The outcome after transphenoidal biopsy was generally favorable. Pre- or postsurgical glucocorticoid treatment was very effective in 75% of the lymphocytic form in reducing the pituitary size. In contrast, glucocorticoid therapy was less effective in granulomatous or xanthomatous hypophysitis. CONCLUSION: Diffuse destruction of the complete pituitary gland including the infundibulum has to be considered in lymphocytic and granulomatous hypophysitis, whereas in xanthomatous, a circumscribed anterior pituitary lesion leading to compression of the pituitary gland without alteration of the pituitary stalk and optic chiasm can be assumed.

A Modified Microsurgical Endoscopic-Assisted Transpedicular Corpectomy of the Thoracic Spine Based on Virtual 3-Dimensional Planning.

BACKGROUND AND OBJECTIVE: The main difficulties of transpedicular corpectomies are lack of space for vertebral body replacement in the neighborhood of critical structures, the necessity for sacrifice of nerve roots in the thoracic spine. and the extent of hemorrhage due to venous epidural bleeding. We present a modified technique of transpedicular corpectomy by using an endoscopic-assisted microsurgical technique performed through a single posterior approach. A 3-dimensional (3D) preoperative reconstruction could be helpful in the planning for this complex anatomic region. METHODS: Surface and volume 3D reconstruction were performed by Amira or the Dextroscope. The clinical experience of this study includes 7 cases, 2 with an unstable burst fracture and 5 with metastatic destructive vertebral body disease, all with significant retropulsion and obstruction of the spinal canal. We performed a comparison with a conventional cohort of transpedicular thoracic corpectomies. RESULTS: Qualitative parameters of the 3D virtual reality planning included degree of bone removal and distance from critical structures such as myelon and implant diameter. Parameters were met in each case, with demonstration of optimal positioning of the implant without neurological complications. In all patients, the endoscope was a significant help in identifying the origins of active bleeding, residual tumor, extent of bone removal, facilitating cage insertion in a minimally invasive way, and helping to avoid root sacrifice on both sides. CONCLUSIONS: Microsurgical endoscopic-assisted transpedicular corpectomy may prove valuable in enhancing the safety of corpectomy in destructive vertebral body disease. The 3D virtual anatomic model greatly facilitated the preoperative planning.

Blurring the boundaries between frame-based and frameless stereotaxy: feasibility study for brain biopsies performed with the use of a head-mounted robot.

OBJECT: Frame-based stereotactic interventions are considered the gold standard for brain biopsies, but they have limitations with regard to flexibility and patient comfort because of the bulky head ring attached to the patient. Frameless image guidance systems that use scalp fiducial markers offer more flexibility and patient comfort but provide less stability and accuracy during drilling and biopsy needle positioning. Head-mounted robot-guided biopsies could provide the advantages of these 2 techniques without the downsides. The goal of this study was to evaluate the feasibility and safety of a robotic guidance device, affixed to the patient's skull through a small mounting platform, for use in brain biopsy procedures. METHODS: This was a retrospective study of 37 consecutive patients who presented with supratentorial lesions and underwent brain biopsy procedures in which a surgical guidance robot was used to determine clinical outcomes and technical procedural operability. RESULTS: The portable head-mounted device was well tolerated by the patients and enabled stable drilling and needle positioning during surgery. Flexible adjustments of predefined paths and selection of new trajectories were successfully performed intraoperatively without the need for manual settings and fixations. The patients experienced no permanent deficits or infections after surgery. CONCLUSIONS: The head-mounted robot-guided approach presented here combines the stability of a bone-mounted set-up with the flexibility and tolerability of frameless systems. By reducing human interference (i.e., manual parameter settings, calibrations, and adjustments), this technology might be particularly useful in neurosurgical interventions that necessitate multiple trajectories.