A simple technique for generating 3D endoscopic images.

Background: Most neurosurgical photographs are limited to two-dimensional (2D), in this sense, most teaching and learning of neuroanatomical structures occur without an appreciation of depth. The objective of this article is to describe a simple technique for obtaining right and left 2D endoscopic images with manual angulation of the optic. Methods: The implementation of a three-dimensional (3D) endoscopic image technique is reported. We first describe the background and core principles related to the methods employed. Photographs are taken demonstrating the principles and also during an endoscopic endonasal approach, illustrating the technique. Later, we divide our process into two sections containing explanations, illustrations, and descriptions. Results: The results of taking a photograph with an endoscope and its assembly to a 3D image has been divided into two parts: Photo acquisition and image processing. Conclusion: We conclude that the proposed method is successful in producing 3D endoscopic images.

Experience With the Endoscopic Contralateral Transmaxillary Approach to the Petroclival Skull Base.

OBJECTIVES/HYPOTHESIS: The contralateral transmaxillary (CTM) approach is a new surgical approach that improves the surgical trajectory relative to the petrous segment of the internal carotid artery (ICA). Here, we present our clinical experience with the CTM approach to the petroclival region of the skull base. STUDY DESIGN: Retrospective review. METHODS: A retrospective review of 29 patients who underwent a CTM approach for skull base pathology from 2015 to 2020 was performed. Assessment of gross total resection (GTR) was based on postoperative imaging. RESULTS: The male:female ratio was 15:14, with an average age of 52 years (range = 19-78 years). Diagnoses included: 12 chondrosarcomas, 11 chordomas, two meningiomas, one schwannoma, one metastasis, one petrous apicitis, and one arachnoid cyst. CTM was performed in addition to a transclival approach and ipsilateral transpterygoid approach in all patients. Reconstruction of surgical defects included a vascularized flap in all but two patients: 24 nasoseptal flaps and three lateral nasal wall flaps. The reconstructive flap was on the same side as the CTM approach in 22 of 28 (79%) patients. There were no ICA injuries. In a subset of patients with chondromatous tumors, GTR of the targeted area was achieved in 16 of 22 (73%) evaluable chondromatous tumors. With a median follow-up of 13 months, 64% of these patients are without disease or dead of other causes; the remainder are alive with disease. CONCLUSIONS: The CTM approach improves the degree of resection of skull base tumors involving the petroclival region using an endoscopic endonasal approach and may minimize risk to the ICA. LEVEL OF EVIDENCE: 4 Laryngoscope, 131:294-298, 2021.

ICAR: endoscopic skull-base surgery.

BACKGROUND: Endoscopic skull-base surgery (ESBS) is employed in the management of diverse skull-base pathologies. Paralleling the increased utilization of ESBS, the literature in this field has expanded rapidly. However, the rarity of these diseases, the inherent challenges of surgical studies, and the continued learning curve in ESBS have resulted in significant variability in the quality of the literature. To consolidate and critically appraise the available literature, experts in skull-base surgery have produced the International Consensus Statement on Endoscopic Skull-Base Surgery (ICAR:ESBS). METHODS: Using previously described methodology, topics spanning the breadth of ESBS were identified and assigned a literature review, evidence-based review or evidence-based review with recommendations format. Subsequently, each topic was written and then reviewed by skull-base surgeons in both neurosurgery and otolaryngology. Following this iterative review process, the ICAR:ESBS document was synthesized and reviewed by all authors for consensus. RESULTS: The ICAR:ESBS document addresses the role of ESBS in primary cerebrospinal fluid (CSF) rhinorrhea, intradural tumors, benign skull-base and orbital pathology, sinonasal malignancies, and clival lesions. Additionally, specific challenges in ESBS including endoscopic reconstruction and complication management were evaluated. CONCLUSION: A critical review of the literature in ESBS demonstrates at least the equivalency of ESBS with alternative approaches in pathologies such as CSF rhinorrhea and pituitary adenoma as well as improved reconstructive techniques in reducing CSF leaks. Evidence-based recommendations are limited in other pathologies and these significant knowledge gaps call upon the skull-base community to embrace these opportunities and collaboratively address these shortcomings.

[Consensus on acute ischemic stroke]. / Consenso sobre accidente cerebrovascular isquémico agudo.

Stroke is the third cause of death and the first cause of disability in Argentina. Ischemic events constitute 80% of cases. It requires the implementation of systematized protocols that allow reducing the time of care, morbidity and mortality. Specialists from nine medical societies related to the care of patients with cerebrovascular disease participated in the consensus. A separate agenda was agreed upon in chapters and for the writing of them, work groups were formed with members of different medical specialties. The level of recommendation was discussed and agreed upon for each topic based on the best clinical evidence available for each of them. An adaptation to the local scope of the recommendations was made when it was considered necessary.The American Heart Association system was used to draft the recommendations and their level of evidence. The correction and editing were done by five external reviewers, who did not participate in the writing and with extensive experience in vascular pathology. Once the preliminary document was finalized, a general meeting was held with all the members of the working groups and the reviewers to reach final recommendations. The consensus covers the management of ischemic stroke in the pre-hospital phase, initial evaluation in the emergency center, recanalization therapies (thrombolysis and/ or mechanical thrombectomy), decompressive craniectomy, neuroimaging and clinical care in the hospital.

El accidente cerebrovascular es la tercera causa de muerte y la primera de discapacidad en la Argentina. Los eventos isquémicos constituyen el 80% de los casos. Los accidentes vasculares cerebrales requieren la implementación de protocolos sistematizados que permitan reducir los tiempos en la atención, la morbilidad y mortalidad. En el consenso participaron especialistas de nueve sociedades médicas relacionadas con la atención de pacientes con enfermedad cerebrovascular. Se consensuó un temario separado en capítulos y para la redacción de los mismos se conformaron grupos de trabajo con miembros de diferentes especialidades médicas. Se discutió y acordó para cada tema el nivel de recomendación en base a la mejor evidencia clínica disponible para cada tópico. Se realizó una adaptación al ámbito local de las recomendaciones cuando se consideró necesario. El sistema de la American Heart Association se utilizó para redactar las recomendaciones y su grado de evidencia. La corrección y edición fue realizada por cinco revisores externos, que no participaron en la redacción y con amplia experiencia en enfermedad vascular. Finalizado el documento preliminar, se organizó una reunión general con todos los integrantes de los grupos de trabajo y los revisores para redactar las recomendaciones definitivas. El consenso abarca la atención del paciente con accidente cerebrovascular isquémico en la fase pre-hospitalaria, evaluación inicial en la central de emergencias, terapias de recanalización (trombolisis y/o trombectomía mecánica), craniectomía descompresiva, neuroimágenes y cuidados clínicos en la internación.

Consenso sobre accidente cerebrovascular isquémico agudo / Consensus on acute ischemic stroke

El accidente cerebrovascular es la tercera causa de muerte y la primera de discapacidad en la Argentina. Los eventos isquémicos constituyen el 80% de los casos. Los accidentes vasculares cerebrales requieren la implementación de protocolos sistematizados que permitan reducir los tiempos en la atención, la morbilidad y mortalidad. En el consenso participaron especialistas de nueve sociedades médicas relacionadas con la atención de pacientes con enfermedad cerebrovascular. Se consensuó un temario separado en capítulos y para la redacción de los mismos se conformaron grupos de trabajo con miembros de diferentes especialidades médicas. Se discutió y acordó para cada tema el nivel de recomendación en base a la mejor evidencia clínica disponible para cada tópico. Se realizó una adaptación al ámbito local de las recomendaciones cuando se consideró necesario. El sistema de la American Heart Association se utilizó para redactar las recomendaciones y su grado de evidencia. La corrección y edición fue realizada por cinco revisores externos, que no participaron en la redacción y con amplia experiencia en enfermedad vascular. Finalizado el documento preliminar, se organizó una reunión general con todos los integrantes de los grupos de trabajo y los revisores para redactar las recomendaciones definitivas. El consenso abarca la atención del paciente con accidente cerebrovascular isquémico en la fase pre-hospitalaria, evaluación inicial en la central de emergencias, terapias de recanalización (trombolisis y/o trombectomía mecánica), craniectomía descompresiva, neuroimágenes y cuidados clínicos en la internación.

Stroke is the third cause of death and the first cause of disability in Argentina. Ischemic events constitute 80% of cases. It requires the implementation of systematized protocols that allow reducing the time of care, morbidity and mortality. Specialists from nine medical societies related to the care of patients with cerebrovascular disease participated in the consensus. A separate agenda was agreed upon in chapters and for the writing of them, work groups were formed with members of different medical specialties. The level of recommendation was discussed and agreed upon for each topic based on the best clinical evidence available for each of them. An adaptation to the local scope of the recommendations was made when it was considered necessary.The American Heart Association system was used to draft the recommendations and their level of evidence. The correction and editing were done by five external reviewers, who did not participate in the writing and with extensive experience in vascular pathology. Once the preliminary document was finalized, a general meeting was held with all the members of the working groups and the reviewers to reach final recommendations. The consensus covers the management of ischemic stroke in the pre-hospital phase, initial evaluation in the emergency center, recanalization therapies (thrombolysis and/ or mechanical thrombectomy), decompressive craniectomy, neuroimaging and clinical care in the hospital.

Diagnosis and endoscopic endonasal management of nontraumatic pseudoaneurysms of the cranial base.

BACKGROUND: Nontraumatic pseudoaneurysms of the cranial base are rare and present unique diagnostic and treatment dilemmas compared with both true aneurysms and pseudoaneurysms outside of the cranial base. There is a dearth of knowledge regarding the management of these complicated lesions. METHODS: Nontraumatic pseudoaneurysms of the cranial base internal carotid artery (ICA) were retrospectively identified at the University of Pittsburgh Medical Center through a key word search of cranial base cases from 2010 to 2017. RESULTS: Three cases were identified, demonstrating pseudoaneurysms of the cavernous and petrous ICA. Each patient underwent diagnostic work-up with computed tomography, magnetic resonance imaging, and angiography, followed by endovascular occlusion and endoscopic endonasal surgery, which resulted in relief of presenting complaints and ablation of the pseudoaneurysm. CONCLUSION: Symptomatic cranial base pseudoaneurysms should undergo treatment to obliterate the aneurysm and relieve the mass effect. First, formal angiography is necessary for accurate diagnosis and treatment planning. Next, endovascular occlusion is performed, with a preference for coiling or endoluminal reconstruction with a flow diverter. Last, endoscopic intervention follows in cases where: (1) decompression of vital structures is indicated; (2) diagnosis of the pseudoaneurysm cannot be definitively confirmed with angiography; or (3) the etiology of the confirmed pseudoaneurysm requires further investigation.

Headache and Treatment of Unruptured Intracranial Aneurysms.

BACKGROUND AND PURPOSE: The relationship between unruptured intracranial aneurysms (UIAs) and chronic headache and the impact of aneurysm treatment on headache outcome are controversial. The aim of this study was to determine clinical features of a supposedly primary headache in patients with UIA. We also assessed changes in headache characteristics after UIA treatment. METHODS: We examined clinical and imaging data of patients in whom a UIA was diagnosed during diagnostic workup of a suspected primary headache. Medical records were reviewed and personal telephone follow-ups were performed after UIA treatment to assess changes in the frequency and intensity of the headache. RESULTS: Forty-two patients (76%) reported a substantial improvement in headache frequency and intensity after UIA treatment. Forty-five patients (81%) reported a decrease in headache frequency from a median of 8 days/month before treatment to 1 day/month after treatment (95% confidence interval [CI] 81-83, P < .001). The average intensity in an analog pain scale was 7.7 ± 1.6 before treatment and 5.6 ± 2.4 after treatment (P < .001). Higher headache frequency was associated with a greater odd of improvement after treatment (odds ratio 1.12, 95% CI 1.0-1.26, P = .03). No associations were found between the type of headache, type of treatment (endovascular versus surgical), number, size, or localization of the aneurysms and the response to treatment. CONCLUSIONS: The treatment of UIA had a robust beneficial effect on previous headache. Although a "placebo" effect of aneurysm treatment cannot be ruled out, these results suggest a potential association between UIA and certain chronic headaches usually considered to be primary.

Total Human Eye Allotransplantation: Developing Surgical Protocols for Donor and Recipient Procedures.

BACKGROUND: Vascularized composite allotransplantation of the eye is an appealing, novel method for reconstruction of the nonfunctioning eye. The authors' group has established the first orthotopic model for eye transplantation in the rat. With advancements in immunomodulation strategies together with new therapies in neuroregeneration, parallel development of human surgical protocols is vital for ensuring momentum toward eye transplantation in actual patients. METHODS: Cadaveric donor tissue harvest (n = 8) was performed with orbital exenteration, combined open craniotomy, and endonasal approach to ligate the ophthalmic artery with a cuff of paraclival internal carotid artery, for transection of the optic nerve at the optic chiasm and transection of cranial nerves III to VI and the superior ophthalmic vein at the cavernous sinus. Candidate recipient vessels (superficial temporal/internal maxillary/facial artery and superficial temporal/facial vein) were exposed. Vein grafts were required for all anastomoses. Donor tissue was secured in recipient orbits followed by sequential venous and arterial anastomoses and nerve coaptation. Pedicle lengths and calibers were measured. All steps were timed, photographed, video recorded, and critically analyzed after each operative session. RESULTS: The technical feasibility of cadaveric donor procurement and transplantation to cadaveric recipient was established. Mean measurements included optic nerve length (39 mm) and caliber (5 mm), donor artery length (33 mm) and caliber (3 mm), and superior ophthalmic vein length (15 mm) and caliber (0.5 mm). Recipient superficial temporal, internal maxillary artery, and facial artery calibers were 0.8, 2, and 2 mm, respectively; and superior temporal and facial vein calibers were 0.8 and 2.5 mm, respectively. CONCLUSION: This surgical protocol serves as a benchmark for optimization of technique, large-animal model development, and ultimately potentiating the possibility of vision restoration transplantation surgery. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, V.

Clinical Considerations for Vascularized Composite Allotransplantation of the Eye.

Vascularized composite allotransplantation represents a potential shift in approaches to reconstruction of complex defects resulting from congenital differences as well as trauma and other acquired pathology. Given the highly specialized function of the eye and its unique anatomical components, vascularized composite allotransplantation of the eye is an appealing method for restoration, replacement, and reconstruction of the nonfunctioning eye. Herein, we describe conventional treatments for eye restoration and their shortcomings as well as recent research and events that have brought eye transplantation closer to a potential clinical reality. In this article, we outline some potential considerations in patient selection, donor facial tissue procurement, eye tissue implantation, surgical procedure, and potential for functional outcomes.

Interfascial Dissection for Protection of the Nerve Branches to the Frontalis Muscles during Supraorbital Trans-Eyebrow Approach: An Anatomical Study and Technical Note.

Introduction Preservation of the temporal branches of the facial nerve during anterolateral craniotomies is important. Damaging it can inflict undesirable cosmetic defects to the patient. The supraorbital trans-eyebrow approach (SOTE) is a versatile keyhole craniotomy but still has a high rate of frontalis muscle (FM) palsy. Objective Anatomical study to implement the interfascial dissection during the SOTE to preserve the nerves to the FM. Methods Slight modification of the standard technique of the SOTE was performed in 6 cadaveric specimens (12 sides). Results Distal rami to the FM were exposed. The standard "u-shape" incision of the FM can cross over the nerves. Alternatively, an "l-shape" incision was performed until the superior temporal line (STL). An interfascial dissection was performed near to the STL and the interfascial fat pad was used as a protective layer for the nerves. Conclusion Various pathologies can be addressed with the SOTE. In the majority of the cases the cosmetic results are good, but FM palsy remains a drawback of this approach. The interfascial dissection may be used in an attempt to prevent frontalis rami palsy.

Use of acoustic Doppler sonography to ascertain the feasibility of the pedicled nasoseptal flap after prior bilateral sphenoidotomy.

OBJECTIVES/HYPOTHESIS: Blood supply to the Hadad-Bassagasteguy pedicled nasoseptal flap may be interrupted by surgery of the pterygopalatine fossa, posterior septectomy, or large sphenoidotomies. This would preclude its use for reconstruction of skull base defects after expanded endonasal approaches (EEA). We present a novel method to ascertain the patency of the nasoseptal artery after prior surgery, and consequently the availability of the nasoseptal flap, using acoustic Doppler sonography. STUDY DESIGN: Retrospective clinical review. METHODS: Four patients who underwent EEAs were evaluated intraoperatively with acoustic Doppler sonography. The mucosa that covers the inferior aspect of the rostrum of the sphenoid sinus was scanned with the tip of the probe. Reflection of sound waves representing intravascular blood flow was assessed. RESULTS: In three patients, the artery was identified in at least one side. One remaining patient showed no acoustic signal suggesting loss of the nasoseptal artery bilaterally, therefore necessitating the use of a fat graft for the reconstruction. CONCLUSIONS: Acoustic Doppler sonography seems to be a feasible and effective way to ascertain the availability of the nasoseptal artery. It is a relatively inexpensive and simple technique that can be performed by any endoscopic surgeon.

Epidemiología de la difilobotriasis en la cuenca del río Valdivia, Chile / Epidemiology of diphyllobothriasis in the Valdivia River basin, Chile

Foram examinadas 1.295 pessoas de seis localidades situadas às margens da bacia do rio Valdivia (Chile), encontrando-se uma prevalência de infecçäo por Diphyllobothrium igual a 1,2% em Rinihue e Las Huellas. Em cäes a prevalência foi de 5,3% e 9,8% em Rinihue e Malihue, respectivamente, näo tendo sido observada infecçäo em gatos nem porcos. Os parasitas obtidos apòs tratamento foram identificados como Diphyllobothrium latum. A infecçäo humana por Diphyllobothrium latum nas áreas afetadas foi produzida pela ingestäo de peixes defumados ou cozidos insuficientemente. A pesquisa realizada em 1.450 peixes pertencentes a 4 espécies introduzidas e 11 autoctones capturadas na bacia do rio Valdivia mostrou a existência de plerocercoides de Diphyllobothrium latum e/ou D. dendriticum nas espécies introduzidas Salmo gairdneri e S. trutta além de outras autoctones. A prevalência ou intensidade média das infecçöes nos peixes bem como o grau de agregaçäo das subpopulaçöes variaram nos diferentes locais estudados. Na bacia do rio Valdivia, alguns peixes atuaram como hospedeiros intermediários e outros como paratênicos das espécies de Diphyllobothrium encontradas. Como medidas de controle nos pontos de difilobotríase nas áreas estudadas sugere-se a melhoria das condiçöes de saneamento básico, educaçäo sanitária e tratamento das pessoas infectadas .

The blood-testis barrier in lizards during the annual spermatogenic cycle

La barrera hemato-testicular, primero descripta en los mamíferos, ha sido recientemente demostrada en la mayoría de los vertebrados y en muchos invertebrados. Nosotros hemos utilizado trazadores electrónicamente densos (hidróxido de lantano) y técnicas de criofractura para estudiar las características morfológicas y de permeabilidad de la barrera hemato-testicular en lagartos que muestran ciclos espermatogénicos anuales (Liolaemus bibroni, ruibali y elongatus y Phymaturus palluma). Durante la actividad de espermatogénesis completa la barera hemato-testicular aisla a todas las células germinales, desde la formación de los complejos sinaptonémicos (espermatocitos cigoténicos), en el compartimiento adluminal del epitelio seminífero. Las características especializaciones de uniones interstolianas, equivalente morfológico de la barrera de permeabilidad, desorganizan durante los períodos estacionales de involución de células germinales concomitantemente con la libre percolación de hidróxido de lantano dentro del compartimiento adluminal del epitelio seminífero. La formación y desorganización ciclica de la barrera hemato-testicular en lagartos refuerza la hipótesis de un control local de las células germinales sobre las especialziaciones de uniones intersertorianas

The blood-testis barrier in lizards during the annual spermatogenic cycle

La barrera hemato-testicular, primero descripta en los mamíferos, ha sido recientemente demostrada en la mayoría de los vertebrados y en muchos invertebrados. Nosotros hemos utilizado trazadores electrónicamente densos (hidróxido de lantano) y técnicas de criofractura para estudiar las características morfológicas y de permeabilidad de la barrera hemato-testicular en lagartos que muestran ciclos espermatogénicos anuales (Liolaemus bibroni, ruibali y elongatus y Phymaturus palluma). Durante la actividad de espermatogénesis completa la barera hemato-testicular aisla a todas las células germinales, desde la formación de los complejos sinaptonémicos (espermatocitos cigoténicos), en el compartimiento adluminal del epitelio seminífero. Las características especializaciones de uniones interstolianas, equivalente morfológico de la barrera de permeabilidad, desorganizan durante los períodos estacionales de involución de células germinales concomitantemente con la libre percolación de hidróxido de lantano dentro del compartimiento adluminal del epitelio seminífero. La formación y desorganización ciclica de la barrera hemato-testicular en lagartos refuerza la hipótesis de un control local de las células germinales sobre las especialziaciones de uniones intersertorianas (AU)