bluuebunny/crossref_metadata_2025 huggingface dataset:
M. Veiskopf. Between the Walls of Fire: A Book on Isaac Babel
Authors: Pogorelskaya E.
Published: November 2018

M. Veiskopf. Between the Walls of Fire: A Book on Isaac Babel.
THE ‘POST-REVOLUTION’ TIME IN Y. TYNYANOV’S NOVEL THE DEATH OF VAZIR-MUKHTAR [SMERT’ VAZIR-MUKHTARA]
Authors: Kiseleva M.
Published: November 2018

The article deals with ‘the time after’ as a ‘literary fact’ in Tynyanov’s novel The Death of Vazir-Mukhtar [Smert’ Vazir-Mukhtara] (1927). The Russian nobles’ defeated coup at the time before coronation of Emperor Nicholas I in December 1825 serves as the book’s historical setting and elucidates the problem of the ‘post-revolution’. The author examines the different types of time (in chapters devoted to Moscow, St. Petersburg, Tiflis, and Persia, respectively) and their function in the novel. She suggests that it is the protagonist’s, A. Griboyedov’s, existential state that determines the time motif in the book. It is argued that the character divided into Griboyedov and Vazir-Mukhtar demarcates his ‘outer’ and ‘inner’ selves. The book’s ideological epicenter lies in the theme of betrayal. The author goes on to show that, despite the circumstances of the ‘time after’, and his loneliness, Griboyedov stays faithful to himself, no matter how hard it is; he remains a creator, a poet and a playwright, who penned the blacklisted Woe from Wit [Gore ot uma], a professional diplomat at the heart of the frustrated project to boost the trade and industry in the Caucasus, and a man of honour and duty to his friends and family. The paper cites a number of arguments, polemicizing with critics of Tynyanov’s novel.
K. CHUKOVSKY AND V. NABOKOV: GLIMPSES OF THEIR PERSONAL AND LITERARY RELATIONSHIPS
Authors: Pudikov I.
Published: November 2018

The relationship between K. Chukovsky and V. Nabokov is a topic little covered by scholars. Even less is written about the mutual literary influence of the two preeminent Russian authors. The article examines their journals, letters and literary works to reveal the development of their artistic disputes.

Doyens of Russian culture, the two simply couldn’t have ignored each other, especially as they met in person before the Revolution and thanks to literary circumstances. The article shows that each one’s personal and artistic opinions were bound to cause a clash of worldviews, which indeed took place on paper, and continued without any face-to-face polemics.

The author finds a lot of similarities in the two writers’ creative method: they both demonstrate astonishing literary erudition, synthesize new imagery, plots and narrative forms. Both favoured formalistic and stylistic experimentation, literary game and cryptography, pranking, puns, allusions, and anagrams.
A. A. Ryabova. Christopher Marlowe and Russian Literature
Authors: Egorova L.
Published: November 2018

A. A. Ryabova. Christopher Marlowe and Russian Literature.
Özel Yetenekli Öğrencilerde İnternet ve Oyun Bağımlılığı ile Algılanan Sosyal Destek Düzeylerinin İncelenmesi
Authors: Yavuz Oğuzhan
Published: November 2018

Bu araştırmanın amacı, Bilim ve Sanat
Merkezine devam eden özel yetenekli öğrencilerin internet ve oyun bağımlılığı
düzeyleri ile algıladıkları sosyal destek düzeylerinin cinsiyet, yaş durumu,
haftalık internet kullanım süresi, internet kullanım amacına göre incelemektir.
Ayrıca internet ve oyun
bağımlılığı düzeyleri ile algılanan sosyal destek düzeyleri arasındaki ilişki
de incelenmiştir. Bu araştırmada ilişkisel tarama deseni kullanılmıştır.  Çalışmaya İstanbul İli içerisinde yer alan Bilim
ve Sanat Merkezlerinde eğitim gören 218 öğrenci katılım göstermiştir. Araştırma
sonucunda demografik değişkenlere bakıldığında internet ve oyun bağımlılığının
cinsiyet, yaş, haftalık internet kullanım süresi, internet kullanım amacına
göre farklılaştığı bulunmuştur. Algılanan sosyal destek düzeyinin ise cinsiyet
ve yaşa göre farklılaştığı bulunmuştur. İnternet ve oyun bağımlılığı ile
algılanan sosyal destek düzeyi arasında negatif yönlü orta düzeyde bir ilişki
olduğu görülmüştür.
Book Reviews
Authors: Thomas Marc Simon , Vohnsen Nina Holm
Published: November 2018

Pitarch, Pedro, Shannon Speed and Xochitl Leyva Solano (eds.). 2008. Human rights in the Maya region: Global politics, cultural contentions, and moral engagements. Durham and London: Duke University Press. ISBN: 978-0-8223-4313-4, x + 377 pp, $23.95

Latour, Bruno (2010 [2002]) The Making of Law. An Ethnography of the Counseil d’État. Polity Press. ISBN-13: 978-0-7456-3985-7
Bringing into View
Authors: Halstead Narmala
Published: November 2018

A new colleague in a recent email communication about this journal posed the question of whether the term ‘legal’ was being put in opposition to ‘illegal’: was there an illegal anthropology? My response must be left in part to the views of other likely interlocutors as to what is or can be evoked when we seemingly endeavour to attach or subdivide anthropology in envisaged specialist areas. The acknowledged spaces to bring out understandings of the legal alongside and within anthropology, in general, through particular frames and representations turn our attention to a dialogical field of knowledge in relation to sociolegal phenomena. I further consider that legal anthropology is not simply, if it ever was, about a type of anthropology called legal, whether opposed to illegal or not, to give a nod to such asides. The wide scholarship eschews any isolated idea of legal in anthropology and incorporates analyses of everyday settings marked, for instance, by implicit and explicit systems of governance and how these are experienced. This also ranges from historical readings of customs and norms to accounts of contemporary rational-legal settings.
From Hope to §3-1
Authors: Bartoszko Aleksandra
Published: November 2018

This article offers insights into the subjectivities that emerge as patients negotiate treatment modalities in Norwegian opioid substitution treatment (OST). In the accounts, I explore patients’ growing engagements with legal imaginaries, and highlight the transformative powers of the law, to develop a concept of the legal self. The analysis shows the power of the law in an imagination of harm and the ways in which the law impacts social and personal change. In the ethnographic insights into the legal structures as a landscape of possibilities for disadvantaged groups, I illustrate the interstices between legal consciousness and mobilisation. This allows for and adds a new dimension to the concept of patienthood beyond the strictly medical experience in which legal narratives provide frames by which people construct meanings for their lived experiences. I consider an examination of both the effectiveness and the effects of the law as crucial for studies of citizenship.
Life at a Tangent to Law
Authors: Rollason Will
Published: November 2018

This article concerns the relationship between motorcycle taxi drivers in Kigali and the legal frameworks that govern their business. While motorcyclists commonly subvert legal processes, or avoid complying with regulations, this should not be understood in terms of their ‘resistance’ to legal orders. To do so would imply that laws are imposed on their social lives from without; however, I show how illegalities help to structure social life by creating ‘mistakes’ that are the basis of social relations. I argue that motorcyclists do not confront legal orders in the idiom of resistance, but neither are they determined or shaped directly by legality. Rather, partially formed by breaches of rules, law is integral to their lives, shaping them indirectly or tangentially, according to the relationships and connections ‘mistakes’ with respect to law enable. Law regulates life not by encoding its rules, but by allowing certain kinds of relationships to form.
Cosmopolitan Politesse
Authors: Rapport Nigel
Published: November 2018

In an earlier work (Anyone: The Cosmopolitan Subject of Anthropology, 2012), I considered a solution to the ‘problem’ of society as identified by Georg Simmel. The fact that we only come to know the interactional ‘Other’ by way of distortion, by virtue of the imposition of alien and alienating labels, categories and taxonomies, Simmel (1971) described as ‘tragic’ (cf. Rapport 2017). We distort the Other’s identity when we ‘know’ them in the conventional and collectivising terms of a symbolic classification of cultural reality. In response, I argued for a linguistic and behavioural style of public address and exchange, and an ethos of good manners, that I termed ‘cosmopolitan politesse’. This was an interactional code by which we presumed the common humanity and the distinct individuality of whomsoever we engaged with, but classified the Other in no more substantive fashion than this. We accepted that in our social interactions we were engaging with an individual human other – ‘Anyone’ – and not with a representative of some more substantive class: ‘a woman’, ‘a Swede’, ‘a Jew’, someone ‘working class’, ‘primitive’ or ‘pious’, and so on.
Radiosensitivity of glioma to Gamma Knife treatment enhanced in vitro and in vivo by RNA interfering Ku70 that is mediated by a recombinant adenovirus
Authors: Jia Qiang , Li Yanhe , Xu Desheng , Li Zhenjiang , Zhang Zhiyuan , Zhang Yipei , Liu Dong , Liu Xiaomin , Pu Peiyu , Kang Chunsheng
Published: November 2018

Object

The authors sought to evaluate modification of the radiation response of C6 glioma cells in vitro and in vivo by inhibiting the expression of Ku70. To do so they investigated the effect of gene transfer involving a recombinant replication-defective adenovirus containing Ku70 short hairpin RNA (Ad-Ku70shRNA) combined with Gamma Knife treatment (GKT).

Methods

First, Ad-Ku70shRNA was transfected into C6 glioma cells and the expression of Ku70 was measured using Western blot analysis. In vitro, phenotypical changes in C6 cells, including proliferation, cell cycle modification, invasion ability, and apoptosis were evaluated using the MTT (3′(4,5-dimethylthiazol-2-yl)2,5-diphenyltetrazolium bromide) assay, Western blot analysis, and cell flow cytometry. In vivo, parental C6 cells transfected with Ad-Ku70shRNA were implanted stereotactically into the right caudate nucleus in Sprague-Dawley rats. After GKS, apoptosis was analyzed using the TUNEL (terminal deoxynucleotidyl transferase–mediated deoxyuridine triphosphate nick-end labeling) method. The inhibitory effects on growth and invasion that were induced by expression of proliferating cell nuclear antigen and matrix metalloproteinase–9 were determined using immunohistochemical analyses.

Results

The expression of Ku70 was clearly inhibited in C6 cells after transfection with Ad-Ku70shRNA. In vitro following transfection, the C6 cells showed improved responses to GKT, including suppression of proliferation and invasion as well as an increased apoptosis index. In vivo following transfection of Ad-Ku70shRNA, the therapeutic efficacy of GKT in rats with C6 gliomas was greatly enhanced and survival times in these animals were prolonged.

Conclusions

Our data support the potential for downregulation of Ku70 expression in enhancing the radiosensitivity of gliomas. The findings of our study indicate that targeted gene therapy–mediated inactivation of Ku70 may represent a promising strategy in improving the radioresponsiveness of gliomas to GKT.
Trigeminal nerve dysfunction after Gamma Knife surgery for trigeminal neuralgia: a detailed analysis
Authors: Matsuda Shinji , Nagano Osamu , Serizawa Toru , Higuchi Yoshinori , Ono Junichi
Published: November 2018

Object

Gamma Knife surgery (GKS) is an effective treatment option for intractable trigeminal neuralgia (TN). The incidence of trigeminal nerve dysfunction, such as facial numbness or dysesthesia, has been reported to be higher than previously published, and the degree and prognosis of trigeminal nerve dysfunction has not been well evaluated. The authors evaluated the incidence, timing, degree, and outcome of trigeminal nerve dysfunction after GKS for TN.

Methods

One hundred four patients with medically refractory TN were treated by GKS. Thirty-nine patients were men and 65 were women; their median age at GKS was 74 years. Using a single isocenter and a 4-mm collimator, 80 or 90 Gy was directed to the trigeminal nerve root. Follow-up data were obtained at clinical examinations every 3–6 months after GKS. Each patient's pain-control status and degree of trigeminal nerve dysfunction were recorded. The incidence, timing, and degree of dysfunction (assessed using the Barrow Neurological Institute facial numbness scale [BNI-N]) and the prognosis and factors related to trigeminal nerve dysfunction were analyzed.

Results

The median duration of follow-up in these patients was 37 months (range 6–121 months). At the final clinical visit, a pain-free status was still observed in 71 patients (68.3%). In 51 patients (49.0%), new or increased trigeminal nerve dysfunction developed at a median of 10.5 months (range 4–68 months) after GKS. In 24 patients (23.1%), this dysfunction was categorized as BNI-N Score II, in 20 patients (19.2%) as BNI-N Score III, and in 7 patients (6.7%) as BNI-N Score IV. Among those patients, 18 patients, including 3 patients with BNI-N Score IV, experienced improvement in nerve dysfunction between 24 and 108 months after GKS (median 52.5 months). At the final clinical visit, 43 patients (41.3%) reported having some trigeminal nerve dysfunction: in 26 patients (25.0%) this was categorized as BNI-N Score II, in 13 patients (12.5%) as BNI-N Score III, and in 4 patients (3.8%) as BNI-N Score IV. The only independent factor that was correlated to all trigeminal nerve dysfunction and also specifically to bothersome trigeminal nerve dysfunction was pain-free status at the final clinic visit.

Conclusions

The incidence of trigeminal nerve dysfunction after GKS for TN was 49%. The severity of the dysfunction improved in one-third of the afflicted patients, even in those with severe dysesthesia at long-term follow-up. A strong relationship between TN and good pain control was identified.
Long-term follow-up studies of Gamma Knife surgery with a low margin dose for vestibular schwannoma
Authors: Sun Shibin , Liu Ali
Published: November 2018

Object

The aim of this study was to assess long-term clinical outcomes in patients who underwent Gamma Knife surgery (GKS) with a low margin dose—14 Gy or less—to treat vestibular schwannoma (VS) unrelated to neurofibromatosis Type II.

Methods

Between December 1994 and December 2001, 200 patients with VSs underwent GKS, which was performed using the Leksell Gamma Knife model B. More than 10 years of follow-up is available in these patients. One hundred ninety patients (88 male and 102 female patients) were followed up using MRI (follow-up rate 95%). The mean age of these patients was 50.6 years (range 10–77 years). Gamma Knife surgery was the primary treatment for VS in 134 cases (70.5%) and was an adjunctive management approach in 56 cases (29.5%). The median tumor margin dose was 13.0 Gy (range 6.0–14.4 Gy), and the median maximum tumor dose was 28.0 Gy (range 15.0–60.0 Gy). The median tumor volume was 3.6 cm3 (range 0.3–27.3 cm3). The median duration of follow-up in these patients was 109 months (range 8–195 months).

Results

In the 190 patients, the latest follow-up MRI studies demonstrated tumor regression in 122 patients (64.2%), stable tumor in 48 patients (25.3%), and tumor enlargement in 20 patients (10.5%). The total rate of tumor control was 89.5%. Using the Kaplan-Meier method, the authors found the estimated 3-, 5-, 10-, and 15-year tumor control rates to be 95%, 93%, 86%, and 79%, respectively; and the estimated 3-, 5-, and 10-year hearing preservation rates to be 96%, 92%, and 70%, respectively. Twenty-six patients (13.7%) exhibited transient mild facial palsy or facial spasm, and 2 patients (1.1%) suffered persistent mild facial palsy. Thirty-nine patients (20.5%) had transient trigeminal neuropathy, and 5 patients (2.6%) suffered from persistent mild facial numbness. The incidence of persistent severe facial and trigeminal neuropathy was 0.0%.

Conclusions

With a low prescribed margin dose of 14 Gy or less, GKS was confirmed to provide long-term tumor control for small to medium-sized VSs and largely to prevent cranial nerves from iatrogenic injury. Based on the findings of this study, GKS is also a reasonable option for the treatment of large, heterogeneously enhancing tumors without symptomatic brainstem compression. Gamma Knife surgery can preserve a high quality of life for most patients with VS who do not have symptomatic brainstem compression. Long-term follow-up is required because of the risk of delayed recurrence of VS.
Long-term results of Gamma Knife surgery for uveal melanomas
Authors: Kang Dong Wan , Lee Sung Chul , Park Yong Gou , Chang Jong Hee
Published: November 2018

Object

Gamma Knife surgery (GKS) is currently believed to be a safe and minimally invasive modality in the treatment of uveal melanomas. It could be used as an alternative treatment to enucleation, preserving the eyeball as well as visual function. The authors report their experiences with GKS for uveal melanomas for the period from February 1998 to December 2006.

Methods

Twenty-two patients with uveal melanoma were enrolled in this study. The population consisted of 12 men and 10 women with a mean age of 53.4 years (range 24–79 years). The mean tumor volume was 877 mm3, and the mean margin dose was 45.6 Gy. The median follow-up period was 67 months (range 3–126 months). All of the patients had received a diagnosis and referral from an ophthalmology clinic; the patients underwent a preoperative orbital examination that included MRI.

Results

Tumor regression was achieved in 20 patients (90.9%), whereas tumor progression was observed in 2 patients (9.1%) 3 years after GKS. The cumulative 1-year and 2-year mean rates of tumor thickness reduction were 18.8% and 42.8%, respectively. The mean rate of tumor volume reduction was 63.7%. The rate of eye retention 5 years after radiosurgery was 77.3% (17 of 22 patients). Overall visual acuity was reduced after GKS in all patients; 14 patients (63.6%) displayed preserved visual function better than hand-movement perception. The most frequent side effect was cataract, which was detected in 9 patients (40.9%); this was followed in frequency by radiation-induced retinopathy in 5 patients (22.7%).

Conclusions

Gamma Knife surgery provides excellent local control of uveal melanomas with a decrease in volume over time. This procedure not only preserves the eyeball and its potential visual function, but also decreases the potential for hematological dissemination and achieves sufficient local tumor control with a gradual reduction in volume.
Gamma Knife surgery for intracranial chordoma and chondrosarcoma: radiosurgical perspectives and treatment outcomes
Authors: Kim Ji Hee , Jung Hyun Ho , Chang Jong Hee , Chang Jin Woo , Park Yong Gou , Chang Won Seok
Published: November 2018

Object

Intracranial chordomas and chondrosarcomas are histologically low-grade, locally invasive tumors that are reported to be similar in terms of anatomical location, clinical presentation, and radiological findings but different in terms of behavior and outcomes. The purpose of this study was to investigate and compare clinical outcomes after Gamma Knife surgery (GKS) for the treatment of intracranial chordoma and chondrosarcoma.

Methods

The authors conducted a retrospective review of the results of radiosurgical treatment of intracranial chordomas and chondrosarcomas. They enrolled patients who had undergone GKS for intracranial chordoma or chondrosarcoma at the Yonsei Gamma Knife Center, Yonsei University College of Medicine, from October 2000 through June 2007. Analyses included only patients for whom the disease was pathologically diagnosed before GKS and for whom more than 5 years of follow-up data after GKS were available. Rates of progression-free survival and overall survival were analyzed and compared according to tumor pathology. Moreover, the association between tumor control and the margin radiation dose to the tumor was analyzed, and the rate of tumor volume change after GKS was quantified.

Results

A total of 10 patients were enrolled in this study. Of these, 5 patients underwent a total of 8 sessions of GKS for chordoma, and the other 5 patients underwent a total of 7 sessions of GKS for chondrosarcoma. The 2- and 5-year progression-free survival rates for patients in the chordoma group were 70% and 35%, respectively, and rates for patients in the chondrosarcoma group were 100% and 80%, respectively (log-rank test, p = 0.04). The 2- and 5-year overall survival rates after GKS for patients in the chordoma group were 87.5% and 72.9%, respectively, and rates for patients in the chondrosarcoma group were 100% and 100%, respectively (log-rank test, p = 0.03). The mean rates of tumor volume change 2 years after radiosurgery were 79.64% and 39.91% for chordoma and chondrosarcoma, respectively (p = 0.05). No tumor progression was observed when margin doses greater than 16 Gy for chordoma and 14 Gy for chondrosarcoma were prescribed.

Conclusions

Outcomes after GKS were more favorable for patients with chondrosarcoma than for those with chordoma. The data also indicated that at 2 years after GKS, the rate of volume change is significantly higher for chordomas than for chondrosarcomas. The authors conclude that radiosurgery with a margin dose of more than 16 Gy for chordomas and more than 14 Gy for chondrosarcomas seems to enhance local tumor control with relatively few complications. Further studies are needed to determine the optimal dose of GKS for patients with intracranial chordoma or chondrosarcoma.
Differences in fixation strength among constructs of atlantoaxial fixation
Authors: Chang Chih-Chang , Huang Wen-Cheng , Tu Tsung-Hsi , Chang Peng-Yuan , Fay Li-Yu , Wu Jau-Ching , Cheng Henrich
Published: November 2018

OBJECTIVE

To avoid jeopardizing an aberrant vertebral artery, there are three common options in placing a C2 screw, including pedicle, pars, and translaminar screws. Although biomechanical studies have demonstrated similar strength among these C2 screws in vitro, there are limited clinical data to address their differences in vivo. When different screws were placed in each side, few reports have compared the outcomes. The present study aimed to evaluate these multiple combinations of C2 screws.

METHODS

Consecutive adult patients who underwent posterior atlantoaxial (AA) fixation were retrospectively reviewed. Every patient uniformly had bilateral C1 lateral mass screws in conjunction with 2 C2 screws (1 C2 screw on each side chosen among the three options: pedicle, pars, or translaminar screws, based on individualized anatomical consideration). These patients were then grouped according to the different combinations of C2 screws for comparison of the outcomes.

RESULTS

A total of 63 patients were analyzed, with a mean follow-up of 34.3 months. There were five kinds of construct combinations of the C2 screws: 2 pedicle screws (the Ped-Ped group, n = 24), 2 translaminar screws (the La-La group, n = 7), 2 pars screws (the Pars-Pars group, n = 6), 1 pedicle and 1 pars screw (the Ped-Pars group, n = 7), and 1 pedicle and 1 translaminar screw (the Ped-La group, n = 19). The rate of successful fixation in each of the groups was 100%, 57.1%, 100%, 100%, and 78.9% (Ped-Ped, La-La, Par-Par, Ped-Par, and Ped-La, respectively). The patients who had no translaminar screw had a higher rate of success than those who had 1 or 2 translaminar screws (100% vs 73.1%, p = 0.0009). Among the 5 kinds of construct combinations, 2 C2 pedicle screws (the Ped-Ped group) had higher rates of success than 1 C2 pedicle and 1 C2 translaminar screw (the Ped-La group, p = 0.018). Overall, the rate of successful fixation was 87.3% (55/63). There were 7 patients (4 in the Ped-La group and 3 in the La-La group) who lost fixation/reduction, and they all had at least 1 translaminar screw.

CONCLUSIONS

In AA fixation, C2 pedicle or pars screws or a combination of both provided very high success rates. Involvement of 1 or 2 C2 translaminar screws in the construct significantly lowered success rates. Therefore, a C2 pars screw is recommended over a translaminar screw.
Updating superficial siderosis of the central nervous system: bleeding of a dorsal osteophyte into the subarachnoid space from a perforating artery
Authors: Brembilla Carlo , Lanterna Luigi Andrea , Bonito Virginio , Gardinetti Margherita , Dorelli Gianluigi , Rampini Angela Dele , Gritti Paolo , Bernucci Claudio
Published: November 2018

Superficial siderosis of the central nervous system (SSCNS) is an uncommon and often unrecognized disorder that results from recurrent and persistent bleeding into the subarachnoid space. Currently, there is no effective treatment for SSCNS. The identification and surgical resolution of the cause of bleeding remains the most reliable method of treatment, but the cause of bleeding is often not apparent. The identified sources of recurrent bleeding have typically included neoplasms, vascular malformations, brachial plexus or nerve root injury or avulsion, and previous head and spinal surgery. An association between recurrent bleeding in the CNS and dural abnormalities in the spine has recently been suggested. Dural tears have been identified in relation to a protruding disc or osteophyte. Also in these patients, the exact mechanism of bleeding remains unknown because of a lack of objective surgical data, even in patients who undergo neurosurgical procedures.

The present case concerns a 48-year-old man who presented with longstanding symptoms of mild hearing loss and mild gait ataxia. A diagnosis of SSCNS was made in light of the patient’s history and the findings on physical examination, imaging, and laboratory testing. MRI and CT detected a small calcific osteophyte in the anterior epidural space of T8–9. The patient underwent surgical removal of the bone spur and dural tear repair. During the surgery, the authors detected a perforating artery, which was on the osteophyte, that was bleeding into the subarachnoid space. This case shows a possible mechanism of chronic bleeding from an osteophyte into the subarachnoid space. In the literature currently available, a perforating artery on an osteophyte bleeding into the subarachnoid space has never been described in SSCNS.
Impact of local steroid application in a minimally invasive transforaminal lumbar interbody fusion: results of a prospective, randomized, single-blind trial
Authors: Haws Brittany E. , Khechen Benjamin , Patel Dil V. , Bawa Mundeep S. , Ahn Junyoung , Bohl Daniel D. , Mayo Benjamin C. , Massel Dustin H. , Guntin Jordan A. , Cardinal Kaitlyn L. , Singh Kern
Published: November 2018

OBJECTIVE

Local epidural steroid application may be associated with decreased pain and narcotic use in the immediate postoperative period following lumbar discectomy. However, local steroid delivery following lumbar fusion procedures has not been well characterized. This study aims to characterize the effect of local intraoperative depomedrol application on perioperative and postoperative outcomes following a single-level minimally invasive transforaminal lumbar interbody fusion (MIS TLIF).

METHODS

A prospective, randomized, single-blinded study was performed. A priori power analysis determined that 86 patients were needed to detect a difference of 1 point in the visual analog scale (VAS) pain score between groups. Ninety-three patients were randomized into depomedrol (DEPO) and no depomedrol (NODEPO) cohorts. Prior to surgical closure, DEPO patients received 1 ml depomedrol (80 mg) applied directly to the surgical site by using a Gelfoam carrier. NODEPO patients received 1 ml saline on the same Gelfoam carrier. Perioperative outcomes including acute postoperative pain and narcotic use were assessed for the duration of inpatient stay. Patient-reported outcomes (PROs) questionnaires including VAS back and leg pain scores, and Oswestry Disability Index (ODI) were administered preoperatively and at 6-week, 12-week, and 6-month follow-up. Outcomes for DEPO and NODEPO cohorts were compared using linear regression controlled for sex.

RESULTS

Of the 93 patients, 45 (48.4%) were randomized to DEPO and 48 (51.6%) to NODEPO. A greater percentage of DEPO patients were female (53.3% vs 27.1%, p = 0.010). There were no other significant differences in patient baseline characteristics. Similarly, operating time, estimated blood loss, and length of inpatient stay did not differ between cohorts. Patients in the DEPO cohort consumed fewer hourly narcotics on postoperative day 0 (5.3 vs 6.3 oral morphine equivalents/hour, p = 0.034). However, no differences in acute postoperative pain or total narcotics consumption were observed between groups. Preoperative VAS leg scores were statistically different between cohorts (p = 0.027). However, preoperative ODI and VAS back scores did not differ between groups. Additionally, DEPO and NODEPO groups experienced similar improvements in PROs at all postoperative time points.

CONCLUSIONS

Local depomedrol use did not lead to decreases in acute postoperative pain or narcotics consumption after MIS TLIF. Additionally, local depomedrol was not associated with postoperative improvements in PROs. The findings of this randomized trial suggest that surgical and clinical outcomes following MIS TLIF may not be impacted by intraoperative application of depomedrol.

Clinical trial registration no.: NCT03308084 (clinicaltrials.gov)
Machine-learning analysis outperforms conventional statistical models and CT classification systems in predicting 6-month outcomes in pediatric patients sustaining traumatic brain injury
Authors: Hale Andrew T. , Stonko David P. , Brown Amber , Lim Jaims , Voce David J. , Gannon Stephen R. , Le Truc M. , Shannon Chevis N.
Published: November 2018

OBJECTIVE

Modern surgical planning and prognostication requires the most accurate outcomes data to practice evidence-based medicine. For clinicians treating children following traumatic brain injury (TBI) these data are severely lacking. The first aim of this study was to assess published CT classification systems in the authors’ pediatric cohort. A pediatric-specific machine-learning algorithm called an artificial neural network (ANN) was then created that robustly outperformed traditional CT classification systems in predicting TBI outcomes in children.

METHODS

The clinical records of children under the age of 18 who suffered a TBI and underwent head CT within 24 hours after TBI (n = 565) were retrospectively reviewed.

RESULTS

“Favorable” outcome (alive with Glasgow Outcome Scale [GOS] score ≥ 4 at 6 months postinjury, n = 533) and “unfavorable” outcome (death at 6 months or GOS score ≤ 3 at 6 months postinjury, n = 32) were used as the primary outcomes. The area under the receiver operating characteristic (ROC) curve (AUC) was used to delineate the strength of each CT grading system in predicting survival (Helsinki, 0.814; Rotterdam, 0.838; and Marshall, 0.781). The AUC for CT score in predicting GOS score ≤ 3, a measure of overall functionality, was similarly predictive (Helsinki, 0.717; Rotterdam, 0.748; and Marshall, 0.663). An ANN was then constructed that was able to predict 6-month outcomes with profound accuracy (AUC = 0.9462 ± 0.0422).

CONCLUSIONS

This study showed that machine-learning can be leveraged to more accurately predict TBI outcomes in children.
Machine learning analyses can differentiate meningioma grade by features on magnetic resonance imaging
Authors: Hale Andrew T. , Stonko David P. , Wang Li , Strother Megan K. , Chambless Lola B.
Published: November 2018

OBJECTIVE

Prognostication and surgical planning for WHO grade I versus grade II meningioma requires thoughtful decision-making based on radiographic evidence, among other factors. Although conventional statistical models such as logistic regression are useful, machine learning (ML) algorithms are often more predictive, have higher discriminative ability, and can learn from new data. The authors used conventional statistical models and an array of ML algorithms to predict atypical meningioma based on radiologist-interpreted preoperative MRI findings. The goal of this study was to compare the performance of ML algorithms to standard statistical methods when predicting meningioma grade.

METHODS

The cohort included patients aged 18–65 years with WHO grade I (n = 94) and II (n = 34) meningioma in whom preoperative MRI was obtained between 1998 and 2010. A board-certified neuroradiologist, blinded to histological grade, interpreted all MR images for tumor volume, degree of peritumoral edema, presence of necrosis, tumor location, presence of a draining vein, and patient sex. The authors trained and validated several binary classifiers: k-nearest neighbors models, support vector machines, naïve Bayes classifiers, and artificial neural networks as well as logistic regression models to predict tumor grade. The area under the curve–receiver operating characteristic curve was used for comparison across and within model classes. All analyses were performed in MATLAB using a MacBook Pro.

RESULTS

The authors included 6 preoperative imaging and demographic variables: tumor volume, degree of peritumoral edema, presence of necrosis, tumor location, patient sex, and presence of a draining vein to construct the models. The artificial neural networks outperformed all other ML models across the true-positive versus false-positive (receiver operating characteristic) space (area under curve = 0.8895).

CONCLUSIONS

ML algorithms are powerful computational tools that can predict meningioma grade with great accuracy.
Utility of deep neural networks in predicting gross-total resection after transsphenoidal surgery for pituitary adenoma: a pilot study
Authors: Staartjes Victor E. , Serra Carlo , Muscas Giovanni , Maldaner Nicolai , Akeret Kevin , van Niftrik Christiaan H. B. , Fierstra Jorn , Holzmann David , Regli Luca
Published: November 2018

OBJECTIVE

Gross-total resection (GTR) is often the primary surgical goal in transsphenoidal surgery for pituitary adenoma. Existing classifications are effective at predicting GTR but are often hampered by limited discriminatory ability in moderate cases and by poor interrater agreement. Deep learning, a subset of machine learning, has recently established itself as highly effective in forecasting medical outcomes. In this pilot study, the authors aimed to evaluate the utility of using deep learning to predict GTR after transsphenoidal surgery for pituitary adenoma.

METHODS

Data from a prospective registry were used. The authors trained a deep neural network to predict GTR from 16 preoperatively available radiological and procedural variables. Class imbalance adjustment, cross-validation, and random dropout were applied to prevent overfitting and ensure robustness of the predictive model. The authors subsequently compared the deep learning model to a conventional logistic regression model and to the Knosp classification as a gold standard.

RESULTS

Overall, 140 patients who underwent endoscopic transsphenoidal surgery were included. GTR was achieved in 95 patients (68%), with a mean extent of resection of 96.8% ± 10.6%. Intraoperative high-field MRI was used in 116 (83%) procedures. The deep learning model achieved excellent area under the curve (AUC; 0.96), accuracy (91%), sensitivity (94%), and specificity (89%). This represents an improvement in comparison with the Knosp classification (AUC: 0.87, accuracy: 81%, sensitivity: 92%, specificity: 70%) and a statistically significant improvement in comparison with logistic regression (AUC: 0.86, accuracy: 82%, sensitivity: 81%, specificity: 83%) (all p < 0.001).

CONCLUSIONS

In this pilot study, the authors demonstrated the utility of applying deep learning to preoperatively predict the likelihood of GTR with excellent performance. Further training and validation in a prospective multicentric cohort will enable the development of an easy-to-use interface for use in clinical practice.
A machine learning approach to predict early outcomes after pituitary adenoma surgery
Authors: Hollon Todd C. , Parikh Adish , Pandian Balaji , Tarpeh Jamaal , Orringer Daniel A. , Barkan Ariel L. , McKean Erin L. , Sullivan Stephen E.
Published: November 2018

OBJECTIVE

Pituitary adenomas occur in a heterogeneous patient population with diverse perioperative risk factors, endocrinopathies, and other tumor-related comorbidities. This heterogeneity makes predicting postoperative outcomes challenging when using traditional scoring systems. Modern machine learning algorithms can automatically identify the most predictive risk factors and learn complex risk-factor interactions using training data to build a robust predictive model that can generalize to new patient cohorts. The authors sought to build a predictive model using supervised machine learning to accurately predict early outcomes of pituitary adenoma surgery.

METHODS

A retrospective cohort of 400 consecutive pituitary adenoma patients was used. Patient variables/predictive features were limited to common patient characteristics to improve model implementation. Univariate and multivariate odds ratio analysis was performed to identify individual risk factors for common postoperative complications and to compare risk factors with model predictors. The study population was split into 300 training/validation patients and 100 testing patients to train and evaluate four machine learning models using binary classification accuracy for predicting early outcomes.

RESULTS

The study included a total of 400 patients. The mean ± SD patient age was 53.9 ± 16.3 years, 59.8% of patients had nonfunctioning adenomas and 84.7% had macroadenomas, and the mean body mass index (BMI) was 32.6 ± 7.8 (58.0% obesity rate). Multivariate odds ratio analysis demonstrated that age < 40 years was associated with a 2.86 greater odds of postoperative diabetes insipidus and that nonobese patients (BMI < 30) were 2.2 times more likely to develop postoperative hyponatremia. Using broad criteria for a poor early postoperative outcome—major medical and early surgical complications, extended length of stay, emergency department admission, inpatient readmission, and death—31.0% of patients met criteria for a poor early outcome. After model training, a logistic regression model with elastic net (LR-EN) regularization best predicted early postoperative outcomes of pituitary adenoma surgery on the 100-patient testing set—sensitivity 68.0%, specificity 93.3%, overall accuracy 87.0%. The receiver operating characteristic and precision-recall curves for the LR-EN model had areas under the curve of 82.7 and 69.5, respectively. The most important predictive variables were lowest perioperative sodium, age, BMI, highest perioperative sodium, and Cushing’s disease.

CONCLUSIONS

Early postoperative outcomes of pituitary adenoma surgery can be predicted with 87% accuracy using a machine learning approach. These results provide insight into how predictive modeling using machine learning can be used to improve the perioperative management of pituitary adenoma patients.
Machine learning applications for the differentiation of primary central nervous system lymphoma from glioblastoma on imaging: a systematic review and meta-analysis
Authors: Nguyen Anthony V. , Blears Elizabeth E. , Ross Evan , Lall Rishi R. , Ortega-Barnett Juan
Published: November 2018

OBJECTIVE

Glioblastoma (GBM) and primary central nervous system lymphoma (PCNSL) are common intracranial pathologies encountered by neurosurgeons. They often may have similar radiological findings, making diagnosis difficult without surgical biopsy; however, management is quite different between these two entities. Recently, predictive analytics, including machine learning (ML), have garnered attention for their potential to aid in the diagnostic assessment of a variety of pathologies. Several ML algorithms have recently been designed to differentiate GBM from PCNSL radiologically with a high sensitivity and specificity. The objective of this systematic review and meta-analysis was to evaluate the implementation of ML algorithms in differentiating GBM and PCNSL.

METHODS

The authors performed a systematic review of the literature using PubMed in accordance with PRISMA guidelines to select and evaluate studies that included themes of ML and brain tumors. These studies were further narrowed down to focus on works published between January 2008 and May 2018 addressing the use of ML in training models to distinguish between GBM and PCNSL on radiological imaging. Outcomes assessed were test characteristics such as accuracy, sensitivity, specificity, and area under the receiver operating characteristic curve (AUC).

RESULTS

Eight studies were identified addressing use of ML in training classifiers to distinguish between GBM and PCNSL on radiological imaging. ML performed well with the lowest reported AUC being 0.878. In studies in which ML was directly compared with radiologists, ML performed better than or as well as the radiologists. However, when ML was applied to an external data set, it performed more poorly.

CONCLUSIONS

Few studies have applied ML to solve the problem of differentiating GBM from PCNSL using imaging alone. Of the currently published studies, ML algorithms have demonstrated promising results and certainly have the potential to aid radiologists with difficult cases, which could expedite the neurosurgical decision-making process. It is likely that ML algorithms will help to optimize neurosurgical patient outcomes as well as the cost-effectiveness of neurosurgical care if the problem of overfitting can be overcome.
Development of machine learning algorithms for prediction of discharge disposition after elective inpatient surgery for lumbar degenerative disc disorders
Authors: Karhade Aditya V. , Ogink Paul , Thio Quirina , Broekman Marike , Cha Thomas , Gormley William B. , Hershman Stuart , Peul Wilco C. , Bono Christopher M. , Schwab Joseph H.
Published: November 2018

OBJECTIVE

If not anticipated and prearranged, hospital stay can be prolonged while the patient awaits placement in a rehabilitation unit or skilled nursing facility following elective spine surgery. Preoperative prediction of the likelihood of postoperative discharge to any setting other than home (i.e., nonroutine discharge) after elective inpatient spine surgery would be helpful in terms of decreasing hospital length of stay. The purpose of this study was to use machine learning algorithms to develop an open-access web application for preoperative prediction of nonroutine discharges in surgery for elective inpatient lumbar degenerative disc disorders.

METHODS

The American College of Surgeons National Surgical Quality Improvement Program was queried to identify patients who underwent elective inpatient spine surgery for lumbar disc herniation or lumbar disc degeneration between 2011 and 2016. Four machine learning algorithms were developed to predict nonroutine discharge and the best algorithm was incorporated into an open-access web application.

RESULTS

The rate of nonroutine discharge for 26,364 patients who underwent elective inpatient surgery for lumbar degenerative disc disorders was 9.28%. Predictive factors selected by random forest algorithms were age, sex, body mass index, fusion, level, functional status, extent and severity of comorbid disease (American Society of Anesthesiologists classification), diabetes, and preoperative hematocrit level. On evaluation in the testing set (n = 5273), the neural network had a c-statistic of 0.823, calibration slope of 0.935, calibration intercept of 0.026, and Brier score of 0.0713. On decision curve analysis, the algorithm showed greater net benefit for changing management over all threshold probabilities than changing management on the basis of the American Society of Anesthesiologists classification alone or for all patients or for no patients. The model can be found here: https://sorg-apps.shinyapps.io/discdisposition/.

CONCLUSIONS

Machine learning algorithms show promising results on internal validation for preoperative prediction of nonroutine discharges. If found to be externally valid, widespread use of these algorithms via the open-access web application by healthcare professionals may help preoperative risk stratification of patients undergoing elective surgery for lumbar degenerative disc disorders.
Impact on the quality of life of patients with arteriovenous malformations during the latent interval between gamma knife radiosurgery and lesion obliteration
Authors: Lai Erica Ho Pik , Lun Samuel Leung Cheong
Published: November 2018

Object. The aim of this study was to measure the quality of life (QOL) in patients with cerebral arteriovenous malformations (AVMs) receiving gamma knife treatment before total AVM obliteration. Quality of life was assessed as it related to the knowledge of rebleeding risk during the waiting period, AVM symptoms, and previous bleeding.

Methods. Thirty-nine patients age 18 years or older without other medical problems were asked to complete a questionnaire that included demographic variables, immediate effect of gamma knife radiosurgery, symptoms of AVM, previous hemorrhage, and the Duke—University of North Carolina Health Profile (63 items).

Conclusions. The QOL of patients with cerebral AVM during the waiting period after undergoing gamma knife treatment was affected by irreversible physical disabilities rather than the knowledge of hemorrhage risk and bleeding experience.
Treatment of arteriovenous malformations using Gamma Knife surgery: the experience at the University of Washington from 2000 to 2005
Authors: Douglas James G. , Goodkin Robert
Published: November 2018

Object

The purpose of this study was to examine the efficacy and toxicity of treating arteriovenous malformations (AVMs) with the model 3C Gamma Knife at the University of Washington Medical Center.

Methods

Ninety-five evaluable patients with 99 treatable AVMs were treated at the University of Washington Medical Center from April 2000 through June 2005. The median patient age at the time of treatment was 40 years (range 6–68 years). The male to female patient ratio was 0.98:1. The median AVM volume treated was 3.8 cm3 (range 0.12–32 cm3). Forty-four percent of the patients had hemorrhaged prior to treatment. The median peripheral Gamma Knife surgery dose was 20 Gy with a median of 12 isocenters treated. The median follow-up duration was 38 months (range 3–91 months). Eighty-one percent of the patients had no previous stereotactic radiosurgery (SRS), whereas the remaining 19% had previously been treated with linear accelerator–based SRS.

Results

The Kaplan–Meier estimated 6-year AVM obliteration rate for the entire cohort was 71.4%. The Kaplan–Meier estimated 6-year obliteration rate was 72% for patients having no prior SRS and 54.5% for those undergoing repeat SRS. The median time to AVM obliteration was 47 months, with 90% of the obliterations occurring between 24 and 58 months. Eight patients (7.4%) experienced late toxicities. There were 2 fatal bleeds and 13 (13.8%) nonfatal bleeds after Gamma Knife surgery.

Conclusions

Gamma Knife surgery is an effective treatment for AVMs, resulting in an excellent obliteration rate with acceptable toxicity.