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Book Review: Youmans and Winn Neurological Surgery, Seventh Edition, 4-Volume Set
No full textIn reviewing the seventh edition of the Neurological Surgery by
Youmans and Winn, the first question arising is whether we still
need an all-encompassing textbook, an opera omnia, on Neurosurgery.
Ours is an age of specialization and even of ultraspecialization.
Being early addressed to a subspecialty is a today’s general
trend for young neurosurgeons and this is certainly functional to
the rapid gathering of a wealth of experience to ensure optimal
patient outcome. Nevertheless neurosurgeons, especially those
young doctors who did not live in a time when neurosurgeons
were able to deal with most of the neurosurgical diseases, run
the risk of losing a more comprehensive understanding of our
discipline—its great beauty as well as its pitfalls.
The intent of providing an encyclopedic overview of neurological
surgery is clearly stated by the authors, and we recognize
that this textbook is, in its own right, an essential reference guide
to both the experienced and nascent clinician.
The first edition of Neurological Surgery by Julian Youmans
appeared in 1973. Since then on, and for each generation
of neurosurgeons, the “Youmans” represented a comprehensive
textbook highlighting the state of the art of neurosurgery, the
techniques and technology of that generation’s contribution to
neurosurgery. Almost 5 decades have passed from that first
edition, and the textbook has expanded to 415 chapters and 5000
pages. By looking through all the editions, we can understand the
long journey made by our knowledge and the breadth reached by
our current practice of neurosurgery.
The second question concerns what a textbook, with ambition
to be considered the bible of the craft of neurosurgery of
the present and next generation, should communicate. If great
attention should be paid to the rise of the technological aspects on
which our discipline is increasingly dependent, all these innovations
make sense if able to improve patient safety and postoperative
quality of life. To this purpose, this seventh edition
dedicates a good number of pages to relevant, but elsewhere
overlooked, themes such as “Improving patient safety,” “Complication
avoidance in neurosurgery,” or “Coagulation in neurosurgery.”
Also, more traditional issues are discussed under original
and modern perspectives (ie, chapter 24, “Brain Retraction”).
The description of pitfalls and complications is always very
difficult. Summarizing in few pages all the circumstances in
which minimal variations from what we plan may result in
an unexpected event with serious implications on the patient’s
healing perspectives, is a great challenge. Equally complicated
would be trying to describe the emotional consequences that
these events may have in the immediacy and on the subsequent
choices. Can a textbook explain to young neurosurgeons
that mastering surgical techniques is sometimes insufficient and
that our results depend substantially on our decision-making?
Probably no. Nonetheless, Neurological Surgery by Youmans and
Winn makes an attempt to explain to the reader this fundamental
issue of the discipline with its “complication avoidance” sections
and especially with the foreword of Henry Marsh, a wonderful
declaration of love and an epitome of the essence of neurosurgery.
A wide section is dedicated to the surgical anatomy as crafted
by Albert Rhoton and his colleagues. The section is combined
with relevant clinical cases and relative videos that make surgical
anatomy much more intelligible. The majority of chapters also
contain related surgical videos, which are all very well prepared
with a suitable length, correct magnification, and appropriate
commentaries. Even though an increasing number of video collections
and multimedia publications are available on the web,
this selected well-prepared electronic material remarkably helps
the understanding of several neurosurgical procedures. Videos
on perioperative techniques such as patient positioning are also
provided, as well as other supplementing basic sciences and
clinical topics. Great attention is paid by the authors to radiological
anatomy, with introductory overviews of brain and spine
imaging and other relevant techniques for diagnosis contained
within each subspecialty section.Other investigational techniques
and, in particular, those that are ancillary to the surgical procedure
such as neurophysiology and functional neuroimaging are also
described in detail.
Controversies in clinical practice, an issue that is really relevant
in this textbook, are presented very clearly in a dedicated section
and at the beginning of all introductory chapters for each of the
12 sections. These introductory chapters, written by each section
editor, review the contents of the section and provide thoughtful
comments while presenting main controversies on the topic.
The textbook contains interesting incursions in the fields of
neuroanesthesia, neurointensive care, and neurourology. All this
material represents an important contribution that can greatly
help the cultural growth of neurosurgeons. Being able to understand
and even handle anesthesiology techniques is crucial to
recognize the risks of surgery and greatly improve surgical performance.
Similarly, a chapter dedicated to the role of the neurosurgeon
in intensive care reminds us that such medical expertise
is a basic and indispensable requirement.
The textbook also tries to dominate the uncountable
knowledge provided by basic science investigations through some
chapters that address themes of obvious interest. Of course, this is
an overwhelming task and well beyond the purpose of the authors
Prediction of diabetes insipidus occurrence after endoscopic endonasal removal of sellar lesions using MRI-based radiomics and machine learning
No full textBACKGROUND: Pituitary adenomas and craniopharyngiomas are the most common lesions of the sellar region. These tumors are responsible for invasion or compression of crucial neurovascular structures. The involvement of the pituitary stalk warrants high rates of both pre- and postoperative diabetes insipidus. The aim of our study was to assess the accuracy of machine learning analysis from preoperative MRI of pituitary adenomas and craniopharyngiomas for the prediction of DI occurrence. METHODS: All patients underwent MRI exams either on a 1.5- or 3-T MR scanner from two Institutions, including coronal T2-weighted (T2w) and contrast-enhanced T1-weighted (CE T1-w) Turbo Spin Echo sequences. Feature selection was carried out as a multi-step process, with a threshold of 0.75 to identify robust features. Further feature selection steps included filtering based on feature variance (threshold >0.01) and pairwise correlation (threshold <0.80). A Bayesian Network model was trained with 10-fold cross validation employing SMOTE to balance classes exclusively within the training folds. RESULTS: Thirty patients were included in this study. In total 2394 features were extracted and 1791 (75%) resulted stable after ICC analysis. The number of variant features was 1351 and of non-colinear features was 125. Finally, 10 features were selected by oneR ranking. The Bayesian Network model showed an accuracy of 63% with a precision of 77% for DI prediction (0.68 area under the precision-recall curve). CONCLUSIONS: We assessed the accuracy of machine learning analysis of texture-derived parameters from preoperative MRI of pituitary adenomas and craniopharyngiomas for the prediction of DI occurrence
Neurosurgery on the web: an analysis of the web-visibility of the European Neurosurgical Societies
No full textBACKGROUND:
Nowadays, internet provides a great opportunity that allows the research community to constantly increase their scientific collaboration, together with information distribution. Aim of this study is to investigate the European National Neurosurgical Societies (ENNS) web-visibility that represents the necessary basis for diffusion of neurosurgical knowledge to both patients and neurosurgeons.
METHODS:
We evaluated the web-visibility of each Neurosurgical Society affiliated to the European Associations of Neurosurgical Societies (EANS) using 3 different parameters: 1) the availability of the full list of all Neurosurgical Centers (NCs) of the country in each ENNS website; 2) the availability of a specific English-written section on the ENNS web-site; 3) the availability of at least one section titled "news and events" and/or "educational" and/or "patient info" on the ENNS website. The web-visibility was categorized in significant (at least 2 out of 3 items fulfilled), not significant (1 out of 3 only) and insufficient (all not fulfilled). We also evaluated the web-visibility of single NCs, and the availability on the web of society's sections dealing with specific neurosurgical topics for each ENNS.
RESULTS:
Through the EANS Website we identified 38 ENNS. The rates of ENNS with significant web-visibility was 39%; 24% of ENNS showed to have a not-significant web-visibility, while 37% had an insufficient visibility. The most unattended criterion was the availability of an English-written section of the website. Among ENNS with a significant web-visibility, this specific criterion was fulfilled in only 53% of cases. This percentage goes down to the 22% for ENNS with a non-significant web-visibility. The full list of NCs was available in 87% of cases for significant profiles and in zero cases for not-significant ones. Finally, the web-visibility rate of single NCs among different ENNS was 80%. Specific sections focusing on specific neurosurgical topics were available in 5 out of 38 ENNS websites (13%).
CONCLUSIONS:
This study highlights the importance of increasing the ENNS web-visibility to spread the neurosurgical knowledge for patients, neurosurgeons and trainees. This could lead to an easier ENNS interaction, increasing the international collaboration between neurosurgical centers in the clinical, research and educational settings
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Aggressive Pituitary Adenomas: The Dark Side of the Moon
No full textAlthough pituitary adenomas are considered benign lesions, a small group may show clinically aggressive behavior, sometimes independently from the classic markers of aggressiveness, including the Ki67 labeling index or p53 expression
Gelatin-thrombin hemostatic matrix in neurosurgical procedures: hemostasis effectiveness and economic value of clinical and surgical procedure-related benefits
No full textBACKGROUND: Gelatin-thrombin hemostatic matrix (FloSeal®) use is associated with shorter surgical times and less blood loss, parameters that are highly valued in neurosurgical procedures. We aimed to assess the effectiveness of gelatin-thrombin in neurosurgical procedures and estimate its economic value.
METHODS: In a 6-month retrospective evaluation at 2 hospitals, intraoperative and postoperative information were collected from patients undergoing neurosurgical procedures where bleeding was controlled with gelatin-thrombin matrix or according to local bleeding control guidelines (control group). Study endpoints were: length of surgery, estimated blood loss, hospitalization duration, blood units utilized, intensive care unit days, postoperative complications, and time to recovery. Statistical methods compared endpoints between the gelatin-thrombin and control groups and resource utilization costs were estimated.
RESULTS: Seventy-eight patients (38 gelatin-thrombin; 40 control) were included. Gelatin-thrombin was associated with a shorter surgery duration than control (166±40 versus 185±55 minutes, P=0.0839); a lower estimated blood loss (185±80 versus 250±95 mL; P=0.0017); a shorter hospital stay (10±3 versus 13±3 days; P<0.001); fewer intensive care unit days (10 days/3 patients and 20 days/4 patients); and shorter time to recovery (3±2.2 versus 4±2.8 weeks; P=0.0861). Fewer gelatin-thrombin patients experienced postoperative complications (3 minor) than the control group (5 minor; 3 major). No gelatin-thrombin patient required blood transfusion; 5 units were administered in the control group. The cost of gelatin-thrombin (€ 268.40/unit) was offset by the shorter surgery duration (difference of 19 minutes at € 858/hour) and the economic value of improved the other endpoint outcomes (i.e., shorter hospital stay, lesser blood loss/lack of need for transfusion, fewer intensive care unit days, and complications).
CONCLUSIONS: The use of gelatin-thrombin hemostatic matrix in patients undergoing neurosurgical procedures was associated with better intra- and postoperative parameters than conventional hemostasis methods, with these parameters having substantial economic benefits
miR-21 and 221 upregulation and miR-181b downregulation in human grade II-IV astrocytic tumors
No full textMicroRNAs (miRNAs) are small noncoding
regulatory RNAs that reduce stability and/or translation of
fully or partially sequence-complementary target mRNAs.
Recent evidence indicates that miRNAs can function both
as tumor suppressors and as oncogenes. It has been demonstrated
that in glioblastoma multiforme miR-21 and 221
are upregulated whereas miR-128 and 181 are downregulated.
Expression of miR-21, 221, 128a, 128b, 128c, 181a,
181b, 181c was studied using real-time quantitative reverse
transcriptase polymerase chain reaction and northern blotting
for human astrocytic tumors with different grade of
malignancy. miR-21 and 221 were overexpressed in glioma
samples, whereas miRNA 181b was downregulated compared
with normal brain tissue. miRNA-21 was
hyperexpressed in all tumor samples whereas higher levels
of miRNA-221 were found in high-grade gliomas. This
study is the first analysis of miRNAs in astrocytic tumor at
different stages of malignancy. The different expression
pattern observed in tumors at different stages ofmalignancy is probably dependent on the cell-specific
repertoire of target genes of tumors sharing different
molecular pathways activity and suggests miRNAs may
have also a place in diagnosis and staging of brain tumors
Aggressive pituitary adenomas: the dark side of the moon
No full textBackground: Although pituitary adenomas are considered benign lesions, a small group may exhibit a clinically aggressive behavior, sometimes independently from the classic markers of aggressiveness, including the Ki67 labeling index and/or p53 expression. Methods: We selected 7 subjects harboring a pituitary tumor with clinical features of aggressiveness. Patients underwent a full preoperative and postoperative endocrinological and neuroradiological work-up. Two were nonfunctioning, two PRL-secreting, two ACTH-secreting, and one a GH-secreting adenoma. Results: The 7 patients underwent a total of 17 surgical procedures. At the first surgical procedure in none of the patients a gross total removal was achieved, whereas a subtotal removal - > 90% of tumor removed - was achieved in 4/7 cases, and a partial removal - < 90% of tumor removed - was achieved in 3/7 cases. At first operation, 4/7 patients showed a Ki67 ≤ 3%, 2/7 > 3% ; it was not available in one patient. Postoperatively, all patients underwent radiation therapy. Three patients received chemotherapy with temozolomide. Three patients underwent peptide receptor radionuclide therapy (PRRT). To date, 1 patient died from tumor progression, two patients are in poor general conditions. The remaining 4 patients are in fair/good conditions, without any major complaints. The mean follow-up is 43.42 months. Conclusions: Aggressive pituitary adenomas represent a specific and still underestimated entity, often diagnosed late. Clinical and neuroradiological rapid progression is often the only marker of aggressiveness. Surgical debulking remains first therapeutic option. Multidisciplinary management is mandatory to offer to these patients targeted therapeutic options
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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