Chiara Negwer

Dr. Chiara Negwer

TUM Fakultät für Medizin, Munich, Germany
orcid

Research Focus & Metrics

Academic Career Length

11Years (2016-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 July 2021 in Brain Stimulation
Verified
Journal Article
Open access
SISebastian Ille
Sebastian Ille
AKAnna Kelm
Anna Kelm
ASAxel Schröder
Axel Schröder
LALucia E. Albers
Lucia E. Albers
CNChiara Negwer
Chiara Negwer
Sandro M KriegSandro M Krieg
Sandro M Krieg
Navigated repetitive transcranial magnetic stimulation (nrTMS) is effective therapy for stroke patients. Neurorehabilitation could be supported by low-frequency stimulation of the non-damaged hemisphere to reduce transcallosal inhibition. The present study examines the effect of postoperative nrTMS therapy of the unaffected hemisphere in glioma patients suffering from acute surgery-related paresis of the upper extremity (UE) due to subcortical ischemia. We performed a randomized, sham-controlled, double-blinded trial on patients suffering from acute surgery-related paresis of the UE after glioma resection. Patients were randomly assigned to receive either low frequency nrTMS (1 Hz, 15 min) or sham stimulation directly before physical therapy for 7 consecutive days. We performed primary and secondary outcome measures on day 1, on day 7, and at a 3-month follow-up (FU). The primary endpoint was the change in Fugl-Meyer Assessment (FMA) at FU compared to day 1 after surgery. Compared to the sham stimulation, nrTMS significantly improved outcomes between day 1 and FU based on the FMA (mean [95% CI] +31.9 [22.6, 41.3] vs. +4.2 [-4.1, 12.5]; P = .001) and the National Institutes of Health Stroke Scale (NIHSS) (-5.6 [-7.5, -3.6] vs. -2.4 [-3.6, -1.2]; P = .02). To achieve a minimal clinically important difference of 10 points on the FMA scale, the number needed to treat is 2.19. The present results show that patients suffering from acute surgery-related paresis of the UE due to subcortical ischemia after glioma resection significantly benefit from low-frequency nrTMS stimulation therapy of the unaffected hemisphere. Local institutional registration: 12/15; ClinicalTrials.gov number: NCT03982329.

1 July 2016 in Journal of Neuroscience Methods
Verified
Journal Article
Closed access
Nico SollmannNico Sollmann
Nico Sollmann
CNChiara Negwer
Chiara Negwer
SISebastian Ille
Sebastian Ille
SMStefanie Maurer
Stefanie Maurer
THTheresa Hauck
Theresa Hauck
Sandro M KriegSandro M Krieg
Sandro M Krieg

20 December 2021 in Brain and Spine
Verified
Journal Article
Open access
HMHanno S. Meyer
Hanno S. Meyer
AWArthur Wagner
Arthur Wagner
TOThomas Obermueller
Thomas Obermueller
CNChiara Negwer
Chiara Negwer
MWMaria Wostrack
Maria Wostrack
BMBernhard Meyer
Bernhard Meyer
Adverse events in surgery are a relevant cause of costs, disability, or death, and their incidence is a key quality indicator that plays an important role in the future of health care. In neurosurgery, little is known about the frequency of adverse events and the contribution of human error. To determine the incidence, nature and severity of adverse events in neurosurgery, and to investigate the contribution of human error. Prospective observation of all adverse events occurring at an academic neurosurgery referral center focusing on neuro-oncology, cerebrovascular and spinal surgery. All 4176 inpatients treated between September 2019 and September 2020 were included. Adverse events were recorded daily and their nature, severity and a potential contribution of human error were evaluated weekly by all senior neurosurgeons of the department. 25.0% of patients had at least one adverse event. In 25.9% of these cases, the major adverse event was associated with human error, mostly with execution (18.3%) or planning (5.6%) deficiencies. 48.8% of cases with adverse events were severe (≥SAVES-v2 grade 3). Patients with multiple adverse events (8.6%) had more severe adverse events (67.6%). Adverse events were more severe in cranial than in spinal neurosurgery (57.6 vs. 39.4%). Adverse events occur frequently in neurosurgery. These data can serve as benchmarks when discussing quality-based accreditation and reimbursement in upcoming health care reforms. The high frequency of human performance deficiencies contributing to adverse events shows that there is potential to further eliminate avoidable patient harm.

15 March 2021 in Cancers
Verified
Journal Article
Open access
PDF file
AAAmir Aftahy
Amir Aftahy
MGMaximilian Groll
Maximilian Groll
MBMelanie Barz
Melanie Barz
AWArthur Wagner
Arthur Wagner
NLNicole Lange
Nicole Lange
JGJens Gempt
Jens Gempt
(1) Background: As resection of trigeminal schwannomas is challenging, due to anatomical involvement of the anterior, middle and posterior fossa, the appropriate approach is important. We report our experience with surgical resection of trigeminal schwannomas by simple and classic skull-base approaches. (2) Methods: We performed a retrospective single-center study including patients who underwent surgery for trigeminal schwannoma tumors between June 2007 and May 2020, concentrating on surgical technique, extent of resection, postoperative outcome and complications. (3) Results: We included 13 patients (median age 57.5 with range of 36-83 years, 53.8% (7/13) female. The most common preoperative clinical presentations were facial pain in six (46.2%), hypoacusis in four (30.8%), trigeminal nerve hypesthesia in 11 (V1 46.2% (6/13), V2 (61.5% (8/13), V3 46.2% (6/13)) and headache in three (23.1%) patients. In three cases, the tumor was resected in a two-stage technique. The intradural subtemporal approach was performed in six cases, the extradural technique in two cases, the retrosigmoid approach in five cases, a Kawase approach in two cases and the transnasal endoscopic approach in one case. The gross total resection rate was 76.9% (10/13) and the median follow-up time 24.0 (0–136) months. Three (23.1%) patients developed postoperative anesthesia in at least one branch of the trigeminal nerve. Trigeminal motor function was preserved in 11 (84.6%) patients. Ten of the 11 patients (76.9%) who reported decreased gustation, cerebellar ataxia, visual impairment, or headache improved postoperatively. Two (15.4%) patients exhibited minimal facial palsy (House and Brackmann II–III), which resolved during the follow-up. The total adverse event rate requiring surgical intervention during follow-up was 7.7%. Surgery-related mortality was 0%. (4) Conclusions: Trigeminal schwannomas are rare benign lesions with intra- and extracranial extension. Considering the low operative morbidity and satisfying functional outcome, gross total resection of trigeminal schwannomas is achievable by classic, but also individually tailored approaches. More invasive or combined techniques were not needed with meticulous surgical planning.

3 November 2020 in Cancers
Verified
Journal Article
Open access
PDF file
AAAmir Aftahy
Amir Aftahy
MBMelanie Barz
Melanie Barz
PKPhilipp Krauss
Philipp Krauss
AWArthur Wagner
Arthur Wagner
NLNicole Lange
Nicole Lange
JGJens Gempt
Jens Gempt
(1) Background: Midline meningiomas such as olfactory groove (OGMs), planum sphenoidale (PSMs), or tuberculum sellae meningiomas (TSMs) are challenging, and determining the appropriate approach is important. We propose a decision algorithm for choosing suitable transcranial approaches. (2) Methods: A retrospective chart review between 06/2007 and 01/2020. Clinical outcomes, radiographic findings, and postoperative complication rates were analyzed with respect to operative approaches. (3) Results: We included 88 patients in the analysis. Of these, 18.2% (16/88) underwent an interhemispheric approach, 72.7% (64/88) underwent a pterional/frontolateral/supraorbital approach, 2.3% (2/88) underwent a unilateral subfrontal approach, and 6.8% (6/88) underwent a bifrontal approach. All OGMs underwent median approaches, along with one PSM. All of the other PSMs and TSMs were resected via lateral approaches. The preoperative tumor volume was ∅20.2 ± 27.1 cm3. Median approaches had significantly higher tumor volume but also higher rates of Simpson I resection (75.0% vs. 34.4%). An improvement of visual deficits was observed in 34.1% (30/88). The adverse event rate was 17.0%. Median follow-up was 15.5 months (range 0–112 months). (4) Conclusions: Median approaches provides satisfying results for OGMs, lateral approaches enable sufficient exposure of the visual apparatus for PSMs and TSMs. In proposing a simple decision-making algorithm, the authors found that satisfactory outcomes can be achieved for midline meningiomas.

22 August 2021 in Cancers
Verified
Journal Article
Open access
PDF file
AAAmir Aftahy
Amir Aftahy
MGMaximilian Groll
Maximilian Groll
MBMelanie Barz
Melanie Barz
Denise BernhardtDenise Bernhardt
Denise Bernhardt
SCStephanie Combs
Stephanie Combs
JGJens Gempt
Jens Gempt
Background: Resection of jugular foramen schwannomas (JFSs) with minimal cranial nerve (CN) injury remains difficult. Reoperations in this vital region are associated with severe CN deficits. Methods: We performed a retrospective analysis at a tertiary neurosurgical center of patients who underwent surgery for JFSs between June 2007 and May 2020. We included nine patients (median age 60 years, 77.8% female, 22.2% male). Preoperative symptoms included hearing loss (66.6%), headache (44.4%), hoarseness (33.3%), dysphagia (44.4%), hypoglossal nerve palsy (22.2%), facial nerve palsy (33.3%), extinguished gag reflex (22.2%), and cerebellar dysfunction (44.4%). We observed Type A, B, C, and D tumors in 3, 1, 1, and 4 patients, respectively. A total of 77.8% (7/9) underwent a retrosigmoid approach, and 33.3% (3/9) underwent an extreme lateral infrajugular transcondylar (ELITE) approach. Gross total resection (GTR) was achieved in all cases. The rate of shunt-dependent hydrocephalus was 22.2% (2/9). No further complications requiring surgical intervention occurred during follow-up. The median follow-up time was 16.5 months (range 3–84 months). Conclusions: Considering the satisfying outcome, the GTR of JFSs is feasible in performing well-known skull base approaches. Additional invasive and complicated approaches were not needed. Radiosurgery may be an effective alternative for selected patients.