Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Online Resource
    Online Resource
    Journal of Neurosurgery Publishing Group (JNSPG) ; 2017
    In:  Journal of Neurosurgery Vol. 127, No. 6 ( 2017-12), p. 1277-1287
    In: Journal of Neurosurgery, Journal of Neurosurgery Publishing Group (JNSPG), Vol. 127, No. 6 ( 2017-12), p. 1277-1287
    Abstract: Nelson-Salassa syndrome (NSS) is a rare consequence of bilateral adrenalectomy (ADX) for refractory hypercortisolism due to Cushing disease (CD). Although classically defined by rapid growth of a large, invasive, adrenocorticotropin hormone (ACTH)–secreting pituitary tumor after bilateral ADX that causes cutaneous hyperpigmentation, visual disturbance, and high levels of ACTH, clinical experience suggests more variability. METHODS The authors conducted a retrospective chart review of all patients 18 years and older with a history of bilateral ADX for CD, adequate pituitary MRI, and at least 2 years of clinical follow-up. Statistical tests included Student's t-test, chi-square test, Fisher's exact test, multivariate analysis, and derived receiver operating characteristic curves. RESULTS Between 1956 and 2015, 302 patients underwent bilateral ADX for the treatment of hypercortisolism caused by CD; 88 had requisite imaging and follow-up (mean 16 years). Forty-seven patients (53%) had radiographic progression of pituitary disease and were diagnosed with NSS. Compared with patients who did not experience progression, those who developed NSS were significantly younger at the time of CD diagnosis (33 vs 44 years, p = 0.007) and at the time of bilateral ADX (35 vs 49 years, p = 0.007), had larger tumors at the time of CD diagnosis (6 mm vs 1 mm, p = 0.03), and were more likely to have undergone external-beam radiation therapy (EBRT, 43% vs 12%, p = 0.005). Among NSS patients, the mean tumor growth was 7 mm/yr (SE 6 mm/yr); the median tumor growth was 3 mm/yr. Prevalence of pathognomonic symptoms was low; the classic triad occurred in 9%, while hyperpigmentation without visual field deficit was observed in 23%, and 68% remained asymptomatic despite radiographic disease progression. NSS required treatment in 14 patients (30%). CONCLUSIONS NSS is a prevalent sequela of CD after bilateral ADX and affects more than 50% of patients. However, although radiological evidence of NSS is common, it is most often clinically indolent, with only a small minority of patients developing the more aggressive disease phenotype characterized by clinically meaningful symptoms and indications for treatment. Young age at the time of CD diagnosis or treatment with bilateral ADX, large tumor size at CD diagnosis, and EBRT are associated with progression to NSS and may be markers of aggressiveness.
    Type of Medium: Online Resource
    ISSN: 0022-3085 , 1933-0693
    RVK:
    RVK:
    Language: Unknown
    Publisher: Journal of Neurosurgery Publishing Group (JNSPG)
    Publication Date: 2017
    detail.hit.zdb_id: 2026156-1
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    In: Journal of Neurosurgery, Journal of Neurosurgery Publishing Group (JNSPG), Vol. 133, No. 3 ( 2020-09), p. 736-741
    Abstract: Radiation dose to the cochlea has been proposed as a key prognostic factor in hearing preservation following stereotactic radiosurgery (SRS) for vestibular schwannoma (VS). However, understanding of the predictive value of cochlear dose on hearing outcomes following SRS for patients with non-VS tumors of the lateral skull base (LSB) is incomplete. The authors investigated rates of hearing loss following high-dose SRS in patients with LSB non-VS lesions compared with patients with VS. METHODS Patients with LSB meningioma or jugular paraganglioma and serviceable pretreatment hearing who underwent SRS treatment during 2007–2016 and received a modiolus dose 〉 5 Gy were included in a retrospective cohort study, along with a similarly identified control group of consecutive patients with sporadic VS. RESULTS Sixteen patients with non-VS tumors and a control group of 43 patients with VS met study criteria. Serviceable hearing, defined as American Academy of Otololaryngology–Head and Neck Surgery class A/B, was maintained in 13 non-VS versus 23 VS patients (81% vs 56%, p = 0.07). All 3 instances of hearing loss in non-VS patients were observed in cerebellopontine angle (CPA) meningiomas. Non-VS with preserved hearing had a median modiolus dose of 6.9 Gy (range 5.7–19.2 Gy), versus 7.4 Gy (range 5.4–7.6 Gy) in those patients with post-SRS hearing loss (p = 0.53). Sporadic VS patients received an overall median modiolus point-dose of 6.8 Gy (range 5.4–11.7 Gy). CONCLUSIONS The modiolus dose threshold of 5 Gy does not predict hearing loss in patients with non-VS tumors undergoing SRS, suggesting that dosimetric parameters derived from VS may not be applicable to this population. Differential rates of hearing loss appear to vary by pathology, with paragangliomas and petroclival meningiomas demonstrating decreased risk of hearing loss compared to CPA meningiomas that may directly compress the cochlear nerve similarly to VS.
    Type of Medium: Online Resource
    ISSN: 0022-3085 , 1933-0693
    RVK:
    RVK:
    Language: Unknown
    Publisher: Journal of Neurosurgery Publishing Group (JNSPG)
    Publication Date: 2020
    detail.hit.zdb_id: 2026156-1
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    Online Resource
    Online Resource
    Journal of Neurosurgery Publishing Group (JNSPG) ; 2019
    In:  Journal of Neurosurgery Vol. 131, No. 5 ( 2019-11), p. 1561-1570
    In: Journal of Neurosurgery, Journal of Neurosurgery Publishing Group (JNSPG), Vol. 131, No. 5 ( 2019-11), p. 1561-1570
    Abstract: Middle fossa surgery is challenging, and reliable surgical landmarks are essential to perform accurate and safe surgery. Although many descriptions of the middle fossa components have been published, a clinically practical description of this very complex anatomical region is lacking. Small structure arrangements in this area are often not well visualized or accurately demarcated with neuronavigation systems. The objective is to describe a “roadmap” of key surgical reference points and landmarks during middle fossa surgery to help the surgeon predict where critical structures will be located. METHODS The authors studied 40 dry skulls (80 sides) obtained from the anatomical board at their institution. Measurements of anatomical structures in the middle fossa were made with a digital caliper and a protractor, taking as reference the middle point of the external auditory canal (MEAC). The results were statistically analyzed. RESULTS The petrous part of the temporal bone was found at a mean of 16 mm anterior and 24 mm posterior to the MEAC. In 87% and 99% of the sides, the foramen ovale and foramen spinosum, respectively, were encountered deep to the zygomatic root. The posterior aspect of the greater superficial petrosal nerve (GSPN) groove was a mean of 6 mm anterior and 25 mm medial to the MEAC, nearly parallel to the petrous ridge. The main axis of the IAC projected to the root of the zygoma in all cases. The internal auditory canal (IAC) porus was found 5.5 mm lateral and 4.5 mm deep to the lateral aspect of the trigeminal impression along the petrous ridge (mean measurement values). A projection from this point to the middle aspect of the root of the zygoma, being posterior to the GSPN groove, could estimate the orientation of the IAC. CONCLUSIONS In middle fossa approaches, the external acoustic canal is a reliable reference before skin incision, whereas the zygomatic root becomes important after the skin incision. Deep structures can be related to these 2 anatomical structures. An easy method to predict the location of the IAC in surgery is described. Careful study of the preoperative imaging is essential to adapt this knowledge to the individual anatomy of the patient.
    Type of Medium: Online Resource
    ISSN: 0022-3085 , 1933-0693
    RVK:
    RVK:
    Language: Unknown
    Publisher: Journal of Neurosurgery Publishing Group (JNSPG)
    Publication Date: 2019
    detail.hit.zdb_id: 2026156-1
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    In: Neurosurgical Focus, Journal of Neurosurgery Publishing Group (JNSPG), Vol. 46, No. 2 ( 2019-02), p. E17-
    Abstract: Sylvian fissure dissection following subarachnoid hemorrhage (SAH) is a challenging but fundamental skill in microneurosurgery, and one that has become increasingly difficult to develop during residency, given the overarching management trends. The authors describe a novel rodent model for simulation of sylvian fissure dissection and cerebrovascular bypass under SAH conditions. METHODS A standardized microvascular anastomosis model comprising rat femoral arteries and veins was used for the experimental framework. In the experimental protocol, following exposure and skeletonization of the vessels, extensive, superficial (1- to 2-mm) soft-tissue debridement was conducted and followed by wound closure and delayed reexploration at intervals of 7, 14, and 28 days. Two residents dissected 1 rat each per time point (n = 6 rats), completing vessel skeletonization followed by end-to-end artery/vein anastomoses. Videos were reviewed postprocedure to assess scar score and relative difficulty of dissection by blinded raters using 4-point Likert scales. RESULTS At all time points, vessels were markedly invested in friable scar, and exposure was subjectively assessed as a reasonable surrogate for sylvian fissure dissection under SAH conditions. Scar score and relative difficulty of dissection both indicated 14 days as the most challenging time point. CONCLUSIONS The authors’ experimental model of femoral vessel skeletonization, circumferential superficial soft-tissue injury, and delayed reexploration provides a novel approximation of sylvian fissure dissection and cerebrovascular bypass under SAH conditions. The optimal reexploration interval appears to be 7–14 days. To the authors’ knowledge, this is the first model of SAH simulation for microsurgical training, particularly in a live animal system.
    Type of Medium: Online Resource
    ISSN: 1092-0684
    Language: Unknown
    Publisher: Journal of Neurosurgery Publishing Group (JNSPG)
    Publication Date: 2019
    detail.hit.zdb_id: 2026589-X
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    Online Resource
    Online Resource
    Ovid Technologies (Wolters Kluwer Health) ; 2015
    In:  Neurosurgery Vol. 62, No. Supplement 1 ( 2015-08), p. 224-
    In: Neurosurgery, Ovid Technologies (Wolters Kluwer Health), Vol. 62, No. Supplement 1 ( 2015-08), p. 224-
    Type of Medium: Online Resource
    ISSN: 0148-396X
    RVK:
    Language: English
    Publisher: Ovid Technologies (Wolters Kluwer Health)
    Publication Date: 2015
    detail.hit.zdb_id: 1491894-8
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    Online Resource
    Online Resource
    Oxford University Press (OUP) ; 2019
    In:  Neuro-Oncology Vol. 21, No. Supplement_6 ( 2019-11-11), p. vi256-vi257
    In: Neuro-Oncology, Oxford University Press (OUP), Vol. 21, No. Supplement_6 ( 2019-11-11), p. vi256-vi257
    Abstract: Glioblastoma (GBM) is a common deadly malignant brain cancer of the central nervous system (CNS), with a median survival of 12–15 months. Scientific advancements are lacking in developing effective therapies for both primary GBM, as well as secondary GBMs, that typically originate as malignant transformation of lower-grade isocitrate dehydrogenase (IDH) 1-mutant tumors. The unique metabolomic profile of IDH1-mutant tumors may present opportunities to develop biomarker signatures of therapeutic efficacy. Microdialysis is an extracellular fluid sampling collection technique utilizing a perfused semipermeable catheter to permit diffusion of molecules between brain interstitium and the perfusate. We hypothesized that microdialysis may identify a metabolomics-based biomarker response to therapy in IDH1-mutant tumors. To test this hypothesis, orthotopic xenografts were generated from two patient-derived GBM lines harboring mutations in IDH1. Perfusates were collected from intra-cranial tumors in aythmic nude mice sampled at baseline and 72h post treatment with temozolomide, an oral alkylating agent used to treat IDH1-mutant gliomas, compared with vehicle treatment, and TMZ-treated non-tumor bearing animals. Perfusates were analyzed via unsupervised metabolomic profiling using both gas and liquid chromatography-mass spectrometry (GC/LC-MS). Tumor specific metabolites such as carnitine and pyruvic acid were detected in microdialysate from tumor bearing mice compared to non-tumor bearing mice. Microdialysis is a feasible technology to identify metabolomics-based biomarker in IDH1-mutant PDX. This work is complemented by parallel analysis of non-IDH1-mutant and TMZ resistant xenografts to yield predictive in vivo tissue biomarkers of drug responsiveness translatable to clinical practice.
    Type of Medium: Online Resource
    ISSN: 1522-8517 , 1523-5866
    Language: English
    Publisher: Oxford University Press (OUP)
    Publication Date: 2019
    detail.hit.zdb_id: 2094060-9
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    In: Neuro-Oncology, Oxford University Press (OUP), Vol. 22, No. Supplement_2 ( 2020-11-09), p. ii192-ii192
    Abstract: Radiotherapy, combined with surgical resection and chemotherapy, remains a first-line treatment for infiltrative gliomas. However, these tumors are not surgically curable, and often recur, even within the prior radiation field, and may demonstrate a more aggressive phenotype. Importantly, high grade gliomas display diverse molecular phenotypes, and whether this genetic variability leads to divergent behaviour in the radiated tumor microenvironment is unknown. Herein, we characterize the effects of the irradiated brain microenvinroment on nine additional unique GBM cell lines to better understand the nuances of how tumor molecular phenotypes influence cellular dynamics. METHODS Female athymic nude mice were randomly divided into cranial radiation (15 Gy) and non-radiated groups. Mice then underwent intracranial implantation with one of the selected patient-derived xenograft (PDX) GBM cell lines (GBM 6, 10, 12, 39, 46, 76, 123, 164, 196; total n=8-15, per group, per line). Kaplan-Meyer (K-M) and log-rank tests were performed to compare the survival between irradiated and non-irradiated groups. RESULT Of nine previously untested human GBM lines, we found that five demonstrated shorter survival in the pre-radiated brain (GBM 6, 46, 76, 164, 196). However, two lines yielded prolonged survival in the pre-radiated brain (GBM 10, 12); GBM 39, 123 whose rate of growth was not impacted by the radiated brain. CONCLUSION These results highlight the likely critical impact of the irradiated microenvironment on tumor behaviour, yet illustrate that different tumors may exhibit opposing responses. Although further evaluation will be needed to understand mechanisms of divergent behavior, our data suggest the increased rate of growth in the radiated microenvironment may not apply to the fastest-growing tumor lines, which could instead demonstrate a paradoxical response.
    Type of Medium: Online Resource
    ISSN: 1522-8517 , 1523-5866
    Language: English
    Publisher: Oxford University Press (OUP)
    Publication Date: 2020
    detail.hit.zdb_id: 2094060-9
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 8
    Online Resource
    Online Resource
    Oxford University Press (OUP) ; 2022
    In:  Neuro-Oncology Vol. 24, No. Supplement_7 ( 2022-11-14), p. vii268-vii269
    In: Neuro-Oncology, Oxford University Press (OUP), Vol. 24, No. Supplement_7 ( 2022-11-14), p. vii268-vii269
    Abstract: Gliomas are genomically heterogeneous tumors that may harness a convergent and therapeutically targetable set of metabolic pathways. At present, the metabolic landscape of in situ human gliomas remains incompletely characterized, hampering translational progress. To that end, we are leveraging the previously untapped potential of high molecular weight microdialysis to determine the global extracellular metabolic profiles of live human gliomas. Under an investigational device exemption, HMW microdialysis ( & lt; 100 kDa) was performed at 2.0 μL/min in an initial discovery cohort of five patients in glioma and adjacent brain during neurosurgical resection; a subsequent cohort of five patients was independently analyzed to critically evaluate results from the discovery group. Untargeted metabolomics via ultra-performance liquid chromatography-tandem mass spectrometry revealed over 300 named metabolites and five drugs from only 20 μL of microdialysate, representing a short and feasible 10 minutes of intraoperative collection time. Enrichment analysis of each patient’s tumor vs. brain ranked extracellular metabolome highlighted marked metabolic convergence within the most aggressive regions of molecular diverse tumors (FDR = 0). Pathway analysis revealed significant enrichment for large neutral amino acid pathways, including valine, leucine, and isoleucine biosynthesis (p=1.6E-9) and degradation (p=0.001) and glycine, serine, and threonine metabolism (p=4.7E-5). Notably, this amino acid signature was not as abundantly present in nonenhancing tumor when compared to enhancing tumor (Average tumor/brain: 1.9x vs. 4.3x, respectively), suggesting upregulation of neutral amino acid transporters in enhancing tumor or delivery from plasma into the CNS via a disrupted BBB. Interestingly, guanidinoacetate (GAA) was our most highly conserved and upregulated metabolite (128.9x in tumor vs. brain). Given its co-production with ornithine, the precursor to protumorigenic polyamines, we posit that GAA may serve as a biomarker of increased ODC activity in live human gliomas. In conclusion, intraoperative HMW microdialysis feasibly offers improved opportunities to perform glioma metabolic biomarker and therapeutic discovery.
    Type of Medium: Online Resource
    ISSN: 1522-8517 , 1523-5866
    Language: English
    Publisher: Oxford University Press (OUP)
    Publication Date: 2022
    detail.hit.zdb_id: 2094060-9
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 9
    Online Resource
    Online Resource
    Ovid Technologies (Wolters Kluwer Health) ; 2022
    In:  Neurosurgery Vol. 68, No. Supplement_1 ( 2022-04), p. 64-64
    In: Neurosurgery, Ovid Technologies (Wolters Kluwer Health), Vol. 68, No. Supplement_1 ( 2022-04), p. 64-64
    Type of Medium: Online Resource
    ISSN: 0148-396X , 1524-4040
    RVK:
    Language: English
    Publisher: Ovid Technologies (Wolters Kluwer Health)
    Publication Date: 2022
    detail.hit.zdb_id: 1491894-8
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 10
    Online Resource
    Online Resource
    Ovid Technologies (Wolters Kluwer Health) ; 2016
    In:  Neurosurgery Vol. 78, No. 2 ( 2016-02), p. 251-255
    In: Neurosurgery, Ovid Technologies (Wolters Kluwer Health), Vol. 78, No. 2 ( 2016-02), p. 251-255
    Type of Medium: Online Resource
    ISSN: 0148-396X
    RVK:
    Language: English
    Publisher: Ovid Technologies (Wolters Kluwer Health)
    Publication Date: 2016
    detail.hit.zdb_id: 1491894-8
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. Further information can be found on the KOBV privacy pages