Head and neck cancer surveillance: The value of computed tomography and clinical exam.

PURPOSE: The recurrence of head and neck cancer (HNC) is most prevalent during the initial two years following curative treatment, underscoring the criticality of regular surveillance for HNC survivors. This study aims to evaluate the effectiveness of computed tomography (CT) imaging and clinical physical examination (CE) in HNC surveillance, assessing whether these imaging protocols meet the current treatment limitations confronting HNC specialists. METHODS: Retrospective chart review of a 9-year experience with head and neck cancer patients at a single, academic tertiary care center. Demographic data was collected along with data regarding whether the recurrences were detected primarily through CE, flexible endoscopic exam (scope exam), or CT or CT/PET scan. Subsets of the data were analyzed and compared by sensitivity, specificity, and negative predictive values. RESULTS: 264 HNC patients were identified. 72 total recurrences (27 %) were noted. The method of initial detection spurring further investigation was imaging in 42 (58.3 %) patients, CE (33.3 %) in 24 patients, scope exam in 6 (8.4 %) patients. Overall, 65 (90.3 %) patients had imaging that showed recurrence regardless of method of initial detection. Sensitivity, (87.1 % vs 70.5 %), and specificity (93.95 % vs 96.9 %) were noted for CT and CE respectively. Combined sensitivity and specificity for CT and CE was 96.2 % and 91.05 % respectively. CONCLUSION: The data suggests that imaging could provide sufficient methods of HNC surveillance despite limitations the COVID-19 pandemic presents.

Correlating area deprivation index with initial stage at presentation and with follow up and recurrence within an advanced practice provider-led survivorship clinic.

INTRODUCTION: Living in disadvantaged neighborhoods has been shown to result in worse healthcare outcomes. The Area Deprivation Index (ADI) is a metric that ranks neighborhoods by socioeconomic disadvantage utilizing numerous factors including income, education, employment, and housing quality. METHODS: A retrospective review of all patients who underwent surveillance in an APP-led head and neck cancer survivorship clinic from Dec 2016 to Oct 2020 at an academic tertiary care center were included. Tumor characteristics, visit frequency, recurrence, number of missed appointments, loss of follow up, and ADI scores were collected. RESULTS: 543 patients were included in the study. A majority were male (69.9 %) and white race (84.9 %) with an average age of 64.6 years old. Average ADI national percentile score was 71.6(range: 17 to 100). ADI national percentile score was not predictive of tumor characteristics at initial presentation: lymphovascular invasion (p = 0.940; OR 1.0 [95 % CI: 0.9 to 1.1]), extranodal extension (p = 0.576; OR 1.0 [95 % CI: 0.9 to 1.2]), positive margins (p = 0.069; OR 0.9 [95 % CI: 0.9 to 1.0]). ADI national percentile score was not significantly correlated with loss to follow up (p = 0.153; OR 1.2 [95 % CI: 0.9 to 1.7] or cancer recurrence (p = 0.594; OR 1.0 [95 % CI: 0.9 to 1.1]). Missing one or more clinic visits was correlated with loss to follow up (p = 0.029; OR 13.1 [95 % CI: 1.3 to 131.7]. CONCLUSION: Living in a disadvantaged neighborhood did not correlate with negative tumor characteristics, loss to follow up, or recurrence within an APP-led survivorship head and neck cancer clinic.

Reirradiation in head and neck squamous cell carcinoma; prognostic indicators, oncologic and functional outcomes.

OBJECTIVES: Patients with recurrent squamous cell carcinoma of the head and neck (HNSCC) have a poor prognosis and limited therapeutic alternatives. While reirradiation is feasible, it is usually associated with high treatment toxicity and is not yet considered the standard of care. Based on current NCCN guidelines, in the context of very advanced head and neck cancer (recurrent and/or persistent disease), surgical intervention is explored initially with/without adjuvants while unresectable disease is approached with radiation and/or systemic therapies. Specific and reliable prognostic indicators for both -oncologic and functional outcomes- have yet to be defined for this population. METHODS: Retrospective chart review of 54 patients treated with reirradiation at a tertiary academic institution between January of 1998 and January of 2024. Only patients with non-metastatic recurrent, and second primary HNSCC were included in the series. Demographics, staging, radiation dose and technique, additional therapy, histopathologic variables, EORTC toxicity, pre- and post-treatment PEG/tracheotomy dependency and oncologic outcomes were retrieved. RESULTS: The study cohort consisted of 54 patients (37 males, 17 females) with HNSCC, averaging 62.7 years in age. Initial tumors were locally advanced in over 42 % of cases, with 58 % being node-negative. The head and cutaneous regions (24.5 %) and tongue (20.8 %) were the most common tumor sites. Primary surgical resection and adjuvant radiation were performed in 47.2 % of cases, and concurrent chemotherapy was used in 40.7 %. Reirradiation was mainly for local or regional recurrence (88.9 %), often following salvage surgery (68.5 %), with a mean dose of 5623 Gy over 52.5 fractions. Positive surgical margins were present in 29.4 % of cases, and extracapsular spread in 59.5 %. No significant differences were found between the salvage surgery and definitive reirradiation groups except for tumor site (P = 0.022). Median follow-up was 52.6 months, with 27 deaths reported. Lymphovascular invasion was significantly correlated with overall survival (P = 0.017), while initial tumor T-stage and neck disease involvement were linked to local-regional control (P = 0.030 and P = 0.033, respectively). Reirradiation increased tracheotomy and PEG-tube dependency by 20 % (P = 0.011) and 23 % (P = 0.003), respectively. CONCLUSIONS: Reirradiation is a feasible therapeutic alternative in recurrent head and neck SCC. Oncologic outcomes observed in this series compare favorably to most published reports. Complete response and perineural invasion were independent prognostic factors for survival and locoregional control. While no mortality directly associated with treatment was observed in this series, reirradiation had a significant impact in functional outcomes in terms of increased risk of tracheotomy and peg tube dependency. Further studies are required to define the role of this treatment in head and neck cancer.

Oncological outcomes of partial thickness calvarial resection for locally advanced scalp malignancies.

OBJECTIVE: Traditionally, locally advanced scalp malignancies have been managed through composite, full-thickness calvarial resection. The aim of this study is to explore the oncologic outcomes of partial calvarial resection for locally invasive scalp malignancies without medullary space invasion, employing a burr-down approach. STUDY DESIGN: Retrospective case series. SETTING: Tertiary referral center. METHODS: This study analyzed records of 26 adult patients diagnosed with scalp cancer that spread to the calvarial region. Data collected included demographics, medical history, adjuvant therapy details, imaging, surgical outcomes, and postoperative oncological results. RESULTS: 26 patients with cancerous scalp lesions necessitating calvarial resection for deep margin control were identified in 22 men and 4 women. Mean age at diagnosis was 72.7 years. The most common histopathological diagnosis was Squamous cell carcinoma (n = 16). Partial removal of the calvarial lesions was achieved in all patients without any intraoperative complications. Twelve patients received adjuvant therapy consisting of the following modalities: radiation (6), chemotherapy (1), immunotherapy (1), a combination of immunotherapy and radiation (2), and a combination of chemotherapy and radiotherapy (2). There was a total of 7 recurrences: local (n = 3,11.5 %), regional (n = 3,11.5 %), distal (n = 1,3.8 %). Long term local control was achieved in (n = 23,88.4 %) of patients. The mean time of follow-up was 19.1 months, and the mean time to recurrence was 15.1 months. CONCLUSION: Partial calvarial resection represents a viable, safe, and effective surgical technique for cancerous tissue removal, reducing risks associated with full thickness calvarial resection, and enhancing soft tissue healing when compared to the established gold standard.

Virtual surgical planning for mandibular reconstruction in an abbreviated admission pathway.

OBJECTIVES: Virtual Surgical Planning (VSP) creates individualized surgical plans for free flap reconstruction of mandibular defects. Prior studies indicate that VSP can offer cost benefits due to reduced operative time and length of stay (LOS). We assessed the impact of VSP in the context of a validated postoperative abbreviated LOS clinical pathway. METHODS: This study assessed patients undergoing VSP vs conventional fibular free flap reconstruction for mandibular defects (12/2015-10/2020) and their operative time, ischemia time, and LOS were evaluated. RESULTS: Forty-four patients underwent VSP reconstruction, while 52 patients underwent conventional reconstruction for mandibular defects. VSP was associated with significantly lower total operative time (6 h and 57 mins vs 7 h and 54 mins, p = 0.011), but not length of stay or ischemia time. Total OR time was significantly increased with increasing number of segments needed in both the VSP group (p = 0.002) and the conventional group (p = 0.015). CONCLUSION: Shorter operative times and LOS have been attributed to the use of VSP in free tissue transfers. It is argued that these reductions offset the added cost of VSP. Our study indicates that there is no cost benefit for VSP utilization due to a significantly reduced operative time with no impact on length of admission in an abbreviated admission clinical pathway following free tissue transfer.

Utility of video fluoroscopic swallow study in advancing oral diet post TORS for oropharyngeal malignancies.

OBJECTIVE: TORS is a minimally invasive surgical alternative to chemoradiotherapy for oropharyngeal malignancies. While early postoperative oropharyngeal dysphagia is linked to TORS, this study explores both subjective and objective swallowing outcomes. STUDY DESIGN: Retrospective and prospective review of the patients who underwent TORS for oropharyngeal malignancy from 2018 to 2023. SETTING: Single tertiary referral center. METHODS: Postoperative transnasal feeding tubes were administered to 142 patients undergoing TORS. Data on oncological, clinical, surgical, and pathological parameters, including VFSS records, pain with swallow, and feeding tube removal timing, were collected. Clinical swallow exam (CSE) was conducted on POD-1, with a formal swallow study pursued if inconclusive. Once a safe swallow was confirmed, oral diets were initiated, and the feeding tube removed, with most patients discharged on POD-2. RESULTS: At an average age of 59.3 years on the day of operation, the palatine tonsil (N = 101) was the predominant subsite. A dobhoff feeding tube was intraoperatively placed in 98 % of patients (N = 139). On POD-1, CSE was conducted in 119 patients, with 26 % (37/119) cleared for total oral diet (NOMS ≥ 4). Additionally, 30 out of 73 VFSS patients were cleared for total oral diet. A total of 54.9 % (78/142) had the feeding tube removed before discharge on POD-2, with a mean time of 6.5 ± 6.6 days. Overall, 71.1 % (101/142) achieved a total oral diet within one week after TORS. CONCLUSION: Early post-TORS swallowing is vital for oropharyngeal malignancies. VFSS assesses post-operative swallowing safety, allowing most patients to resume total oral nutrition shortly after TORS.

Implementation of a Real-Time Brain-to-Brain Synchrony Estimation Algorithm for Neuroeducation Applications.

This study centers on creating a real-time algorithm to estimate brain-to-brain synchronization during social interactions, specifically in collaborative and competitive scenarios. This type of algorithm can provide useful information in the educational context, for instance, during teacher-student or student-student interactions. Positioned within the context of neuroeducation and hyperscanning, this research addresses the need for biomarkers as metrics for feedback, a missing element in current teaching methods. Implementing the bispectrum technique with multiprocessing functions in Python, the algorithm effectively processes electroencephalography signals and estimates brain-to-brain synchronization between pairs of subjects during (competitive and collaborative) activities that imply specific cognitive processes. Noteworthy differences, such as higher bispectrum values in collaborative tasks compared to competitive ones, emerge with reliability, showing a total of 33.75% of significant results validated through a statistical test. While acknowledging progress, this study identifies areas of opportunity, including embedded operations, wider testing, and improved result visualization. Beyond academia, the algorithm's utility extends to classrooms, industries, and any setting involving human interactions. Moreover, the presented algorithm is shared openly, to facilitate implementations by other researchers, and is easily adjustable to other electroencephalography devices. This research not only bridges a technological gap but also contributes insights into the importance of interactions in educational contexts.

Wearable Biosensor Technology in Education: A Systematic Review.

Wearable Biosensor Technology (WBT) has emerged as a transformative tool in the educational system over the past decade. This systematic review encompasses a comprehensive analysis of WBT utilization in educational settings over a 10-year span (2012-2022), highlighting the evolution of this field to address challenges in education by integrating technology to solve specific educational challenges, such as enhancing student engagement, monitoring stress and cognitive load, improving learning experiences, and providing real-time feedback for both students and educators. By exploring these aspects, this review sheds light on the potential implications of WBT on the future of learning. A rigorous and systematic search of major academic databases, including Google Scholar and Scopus, was conducted in accordance with the PRISMA guidelines. Relevant studies were selected based on predefined inclusion and exclusion criteria. The articles selected were assessed for methodological quality and bias using established tools. The process of data extraction and synthesis followed a structured framework. Key findings include the shift from theoretical exploration to practical implementation, with EEG being the predominant measurement, aiming to explore mental states, physiological constructs, and teaching effectiveness. Wearable biosensors are significantly impacting the educational field, serving as an important resource for educators and a tool for students. Their application has the potential to transform and optimize academic practices through sensors that capture biometric data, enabling the implementation of metrics and models to understand the development and performance of students and professors in an academic environment, as well as to gain insights into the learning process.

Neuroimaging in the diagnosis and treatment of intracranial pressure disorders.

OBJECTIVE: To review the clinical features, proposed pathophysiology, and the role of medical imaging in the diagnosis and treatment of idiopathic intracranial hypertension and spontaneous intracranial hypotension. METHODS: The authors conducted a narrative review of the current literature on intracranial hypertension and hypotension syndromes, with a focus on imaging findings and role of neurointerventional radiology as a therapeutic option for these pathologies. RESULTS: Idiopathic intracranial hypertension commonly presents in obese women of childbearing age, being headache and papilledema the main clinical manifestations. Characteristic radiological findings consist of increased cerebrospinal fluid around the optic nerve, partially empty sella turcica and stenosis of the transverse sinuses. Transverse sinus stenting is a treatment alternative that has proven valuable utility in the recent years. Spontaneous intracranial hypotension in most of cases presents with orthostatic headache and has predilection for female population. The typical radiological features in the brain consist of subdural fluid collections, enhancement of the dura, engorgement of the venous structures, pituitary enlargement, and sagging of the brain. In this pathology, a cerebrospinal fluid leak in the spine associated with a defect in the dura, meningeal diverticulum, or a cerebrospinal fluid-venous leak must be actively ruled out. CONCLUSIONS: Neurologic complaints secondary to changes in intracranial pressure exhibit certain clinical features that in combination with fairly specific radiological patterns allow a highly accurate diagnosis. The diverse specialists in neurosciences should be aware of the multiple image modalities in the study of these syndromes as well as the treatment alternatives by neurointerventional radiology.

Comparing donor site morbidity in osteocutaneous radial forearm versus fibula free flap for mandibular reconstruction.

PURPOSE: The osteocutaneous radial forearm free flap has gained popularity as a less morbid option for oromandibular reconstruction compared to the fibular free flap. However, there is a paucity of data regarding direct outcome comparison between these techniques. METHODS: Retrospective chart review of 94 patients who underwent maxillomandibular reconstruction intervened from July 2012-October 2020 at the University of Arkansas for Medical Sciences. All other bony free flaps were excluded. Endpoints retrieved encompassed demographics, surgical outcomes, perioperative data, and donor site morbidity. Continuous data points were analyzed using independent sample t-Tests. Qualitative data was analyzed using Chi-Square tests to determine significance. Ordinal variables were tested using the Mann-Whitney U test. RESULTS: The cohort was equally male and female, with a mean age of 62.6 years. There were 21 and 73 patients in the osteocutaneous radial forearm free flap and fibular free flap cohorts, respectively. Excluding age, the groups were otherwise comparable, including tobacco use, and ASA classification. Bony defect (OC-RFFF = 7.9 cm, FFF = 9.4 cm, p = 0.021) and skin paddle (OC-RFFF = 54.6 cm2, FFF = 72.21 cm2, p = 0.045) size were larger in the fibular free flap group. However, no significant difference was found between cohorts with respect to skin graft. There was no statistically significant difference between cohorts regarding the rate of donor site infection, tourniquet time, ischemia time, total operative time, blood transfusion, or length of hospital stay. CONCLUSIONS: No significant difference in perioperative donor site morbidity was found between patients undergoing fibular forearm free flap and osteocutaneous radial forearm flap for maxillomandibular reconstruction. Osteocutaneous radial forearm flap performance was associated with significantly older age, which may represent a selection bias.

Fabrication, Characterization and Performance of Low Power Gas Sensors Based on (GaxIn1-x)2O3 Nanowires.

Active research in nanostructured materials aims to explore new paths for improving electronic device characteristics. In the field of gas sensors, those based on metal oxide single nanowires exhibit excellent sensitivity and can operate at extremely low power consumption, making them a highly promising candidate for a novel generation of portable devices. The mix of two different metal oxides on the same nanowire can further broaden the response of this kind of gas sensor, thus widening the range of detectable gases, without compromising the properties related to the active region miniaturization. In this paper, a first study on the synthesis, characterization and gas sensing performance of (GaxIn1-x)2O3 nanowires (NWs) is reported. Carbothermal metal-assisted chemical vapor deposition was carried out with different mixtures of Ga2O3, In2O3 and graphite powders. Structural characterization of the NWs revealed that they have a crystalline structure close to that of In2O3 nanowires, with a small amount of Ga incorporation, which highly depends on the mass ratio between the two precursors. Dedicated gas nanosensors based on single NWs were fabricated and tested for both ethanol and nitrogen dioxide, demonstrating an improved performance compared to similar devices based on pure In2O3 or Ga2O3 NWs.

[Fecal occult blood test for colorectal cancer screening]. / Test de sangre oculta en deposiciones para programas de cribado de cáncer colorrectal: actualización.

Screening programs for colorectal cancer (CRC) are standard in most developed countries because they reduce mortality and are cost-effective. Within them, colonoscopy allows to directly visualize the colon and remove neoplastic lesions. However, it is an expensive exam with low adherence in asymptomatic individuals. The fecal occult blood test (FOBT) is a low-cost and risk-free method for the user, which results in a high rate of adherence, explaining its use in most screening programs. This article analyzes the effectiveness of different fecal occult blood tests in screening programs. The main conclusions are that the sensitivity of the guaiac-based chemical test for the detection of colorectal cancer is lower than that observed with qualitative and quantitative immunological tests. Automated quantitative methods allow objective readings independent of the operator and the reaction reading time, necessary for the analysis of large numbers of samples. The participation rate with immunological FOBTs is higher than with chemical ones, which is why they are preferred by the different countries that have screening programs. The use of quantitative tests allows stratification of symptomatic and asymptomatic patients at higher risk, in the screening programs.

[Descriptive epidemiology and frequency variations of astrocytic tumors in the National Institute of Neurology and Neurosurgery of Mexico]. / Epidemiología descriptiva y cambios en la frecuencia de tumores astrocíticos en el Instituto Nacional de Neurología y Neurocirugía de México.

OBJECTIVE: To determine distribution, localization and frequency variations of astrocytic tumors (AT) in a Mexican Institute of neurology. MATERIALS AND METHODS: Institutional registries of AT from five decades were analyzed. AT/ Surgical discharges (SD) and AT/Central Nervous System Tumors (CNST) from 1995 to 2014 were compared. RESULTS: Two thousand two hundred and eighty-seven AT (1 356 men and 931 women) were analyzed. The most common glioma was glioblastoma multiforme (GBM), found in young adults with a higher frequency to that reported in other studies. Relation of AT/SD, as well as, relation of AT/CNST was similar between 1995 and 2014. CONCLUSIONS: In general, the frequency of AT worldwide, being higher in the subgroup of young adults with GBM. There was not significant variation in the frequency of AT during the time studied.

OBJETIVO: Determinar distribución, localización y cambios de la frecuencia de tumores astrocíticos (TA) en un instituto mexicano de neurología. MATERIAL Y MÉTODOS: Se revisaron los registros institucionales de TA de cinco décadas. Se compararon las relaciones TA/egresos quirúrgicos (EQ) y TA/total de tumores del sistema nervioso central (TSNC) de 1995 a 2014. RESULTADOS: Se analizaron 2 287 TA (1 356 en hombres y 931 en mujeres). El glioma más común fue el glioblastoma multiforme (GBM), que estuvo presente en adultos jóvenes con una frecuencia mayor a la reportada en otros estudios. La relación TA/EQ y TA/TNSC fue similar entre 1995 y 2014. CONCLUSIONES: En general, la frecuencia de TA atendidos en el Instituto es similar a la reportada internacionalmente. No obstante, los casos de TA en el subgrupo de adultos jóvenes con GBM son más frecuentes (40%) que las incidencias reportadas en otros estudios (menores al 5%). No se encontró variación significativa en la frecuencia de TA durante las últimas dos décadas.

Characterization of Pax3 and Sox10 transgenic Xenopus laevis embryos as tools to study neural crest development.

The neural crest is a multipotent population of cells that originates a variety of cell types. Many animal models are used to study neural crest induction, migration and differentiation, with amphibians and birds being the most widely used systems. A major technological advance to study neural crest development in mouse, chick and zebrafish has been the generation of transgenic animals in which neural crest specific enhancers/promoters drive the expression of either fluorescent proteins for use as lineage tracers, or modified genes for use in functional studies. Unfortunately, no such transgenic animals currently exist for the amphibians Xenopus laevis and tropicalis, key model systems for studying neural crest development. Here we describe the generation and characterization of two transgenic Xenopus laevis lines, Pax3-GFP and Sox10-GFP, in which GFP is expressed in the pre-migratory and migratory neural crest, respectively. We show that Pax3-GFP could be a powerful tool to study neural crest induction, whereas Sox10-GFP could be used in the study of neural crest migration in living embryos.

Are There Mandibular Morphological Differences in the Various Facial Asymmetry Etiologies? A Tomographic Three-Dimensional Reconstruction Study.

PURPOSE: Facial asymmetries (FAs) have been classified according to the mandibular morphological differences to obtain better diagnostic and treatment decisions. The purpose of the present study was to establish diagnostic differentiation among FAs using computed tomography (CT) and 3-dimensional (3D) reconstruction. MATERIALS AND METHODS: We performed a cross-sectional study of patients with a diagnosis of FA, who had been evaluated by CT and 3D reconstruction in the same clinical center from 2015 to 2018. The following mandibular anatomic characteristics were compared between the 2 sides (deviated side vs contralateral side) and type of FA: condylar length, mandibular ramus length and width, mandibular body length, and symphysis deviation. RESULTS: The 53 patients included 23 men and 30 women (age range, 16 to 25 years). Six categories of FA were identified: hemimandibular elongation (n = 25), hemimandibular hyperplasia (n = 2), hybrid hyperplasia (n = 3), asymmetric mandibular prognathism (n = 14), asymmetry of the glenoid fossa (n = 2), and functional laterognathism (n = 7). The condylar length and mandibular ramus width were greater in the displaced side than in the contralateral side, with differences of -2.0 ± 2.8 mm (P < .001) and -0.5 ± 1.7 mm (P = .009), respectively. The mandibular body length was greater on the contralateral side (mean difference, 2.1 ± 3.5 mm; P < .001). The symphysis deviation was 5.0 ± 3.4 mm, and those with a hybrid form presented with a greater deviation, with values greater than 10 mm, followed by those with hemimandibular elongation. CONCLUSIONS: The evaluation of the CT images and 3D reconstructions in patients with FA provided detailed information of the mandibular structure that is useful to compare the differences between sides and to classify the entities associated with FA.

Challenging the osseous component of sphenoorbital meningiomas.

BACKGROUND: Intraosseous growth is a unique feature of sphenoorbital meningiomas (SOM). Its close relation to neurovascular structures limits complete surgical resection and possibly contributes to the high recurrence rate. OBJECTIVE: To evaluate the growth behavior of intraosseous remnants and develop a protocol for precise intraoperative visualization of intraosseous SOM. METHODS: We included 31 patients operated for SOM from 2004 to 2017. The growth velocity of the intraosseous tumor component was volumetrically calculated in 20 cases. To improve accuracy of image guidance, we implemented a specialized bone surface-based registration algorithm. For intraoperative bone visualization, we included CT in multimodality continuous image guidance in 23 patients. The extent of resection (EOR) was compared with a standard MR-only navigation group (n = 8). RESULTS: In 11/20 cases (55%), a progressive regrowth of the intraosseous SOM remnant was noted during a mean follow-up of 52 months (range 20-132 months). We observed a mean increase of 6.2 cm3 (range 0.2-23.7 cm3) per patient and side during the follow-up period. Bone surface-based registration was significantly more accurate than skin surface-based registration (mean 0.7 ± 0.4 mm and 1.9 ± 0.7 mm, p < 0.001). The EOR of the intraosseous component was significantly higher using CT + MRI navigation compared with controls (96% vs. 81%, p = 0.044). CONCLUSION: Quantitative assessment of the biological behavior of intraosseous remnants revealed a continuous slow growth rate independent of the soft tumor component of more than half of SOM. According to our data, application of a multimodal image guidance provided high accuracy and significantly increased the resection rate of the intraosseous component of SOM.

Post-Condylectomy Histopathologic Findings in Patients With a Positive 99mTc Methylene Diphosphonate Single-Photon Emission Computed Tomographic Diagnosis for Condylar Hyperplasia.

PURPOSE: To describe and correlate with age the histopathologic findings observed in a group of specimens obtained from patients who underwent high condylectomy. MATERIALS AND METHODS: In this cross-sectional study, 27 condylar specimens from patients with facial asymmetry, suspected condylar hyperplasia (CH), and a positive diagnosis by single photon emission computed tomography (SPECT) were evaluated. Histopathologic variables measured in the mandibular condyles were thickness of fibrous, proliferative, and hyperplasic cartilage layers and total tissue thickness. RESULTS: The thickness of the fibrous layer (P = .014) and proliferative layer (P = .005) and total thickness (P = .007) were significantly greater in the patients studied compared with the literature reference values, and 66.6% of cases presented cartilage islands in the calcified region. Seventeen patients no older than 22 years (85%) showed this finding, whereas only 1 patient at least 23 years old did. Therefore, the presence of cartilage islands was significantly related to age (P = .001). CONCLUSIONS: Altogether, the histopathologic findings are consistent with the positive SPECT diagnosis of CH. Histopathologic evaluation showed an increased thickness in the soft tissue layer of the affected mandibular condyle, which was particularly marked for the proliferative layer. Cartilage islands were found mostly in patients no older than 22 years. Therefore, it is not a reliable pathognomic sign for CH because it could be related to normal condylar growth.

[Acute severe ulcerative colitis treated with accelerated infliximab induction. Case report]. / Terapia de inducción acelerada con infliximab en paciente con colitis ulcerosa grave refractaria a corticoides. Caso clínico.

Acute severe ulcerative colitis (ASUC) is a potentially life-threatening condition that requires early recognition, hospitalization and adequate treatment. Currently, the use of infliximab in ulcerative colitis (UC) is recommended in the case of severe disease refractory to corticosteroids, once that superimposed bacterial or viral infections (such as cytomegalovirus or Clostridium difficile) have been excluded. However, conventional weight-based regimens of infliximab might be insufficient for patients with ASUC. Accelerated infliximab induction regimen may increase its serum concentration levels and efficacy by reducing early colectomy rates in these patients. We report a 34 year old female presenting with an ASUC. She was initially treated with hydrocortisone 300 mg/day and mesalazine enemas 4 g/day with an unfavorable clinical response. At the fifth day of therapy, an accelerated induction therapy with infliximab was started in doses of 10 mg/kg at weeks 0, 1 and 4. After the second dose, there was a favorable response with reduction of abdominal pain, stool frequency and hematochezia. She was discharged with prednisone and azathioprine. After a year of starting infliximab, the patient remains in clinical remission.

Regeneration of Xenopus laevis spinal cord requires Sox2/3 expressing cells.

Spinal cord regeneration is very inefficient in humans, causing paraplegia and quadriplegia. Studying model organisms that can regenerate the spinal cord in response to injury could be useful for understanding the cellular and molecular mechanisms that explain why this process fails in humans. Here, we use Xenopus laevis as a model organism to study spinal cord repair. Histological and functional analyses showed that larvae at pre-metamorphic stages restore anatomical continuity of the spinal cord and recover swimming after complete spinal cord transection. These regenerative capabilities decrease with onset of metamorphosis. The ability to study regenerative and non-regenerative stages in Xenopus laevis makes it a unique model system to study regeneration. We studied the response of Sox2(/)3 expressing cells to spinal cord injury and their function in the regenerative process. We found that cells expressing Sox2 and/or Sox3 are present in the ventricular zone of regenerative animals and decrease in non-regenerative froglets. Bromodeoxyuridine (BrdU) experiments and in vivo time-lapse imaging studies using green fluorescent protein (GFP) expression driven by the Sox3 promoter showed a rapid, transient and massive proliferation of Sox2(/)3(+) cells in response to injury in the regenerative stages. The in vivo imaging also demonstrated that Sox2(/)3(+) neural progenitor cells generate neurons in response to injury. In contrast, these cells showed a delayed and very limited response in non-regenerative froglets. Sox2 knockdown and overexpression of a dominant negative form of Sox2 disrupts locomotor and anatomical-histological recovery. We also found that neurogenesis markers increase in response to injury in regenerative but not in non-regenerative animals. We conclude that Sox2 is necessary for spinal cord regeneration and suggest a model whereby spinal cord injury activates proliferation of Sox2/3 expressing cells and their differentiation into neurons, a mechanism that is lost in non-regenerative froglets.

Historical distribution of central nervous system tumors in the Mexican National Institute of Neurology and Neurosurgery.

OBJECTIVE: To determine the frequency of central nervous system (CNS) tumors in the first fifty years of the National Institute of Neurology and Neurosurgery of Mexico Manuel Velasco Suárez (Instituto Nacional de Neurología y Neurocirugía de México, INNN) from 1965 to 2014. MATERIALS AND METHODS: A total of 16 116 institutional records of CNS tumors were analyzed. The frequency and distribution of CNS tumors were evaluated by tumor type, patient age and patient gender. The annual relationship between CNS tumors and surgical discharges (SD) over the last 20 years was estimated. RESULTS: The frequencies of most CNS tumors were consistent with those found worldwide, and the most common tumors were neuroepithelial tumors (33%), particularly astrocytic tumors (67%); meningeal tumors (26%); and pituitary tumors (20%). The incidence of pituitary tumors in these data was twice as high as that reported in other regions of the world, and the relationship between CNS tumors and SD was consistent over time (0.22-0.39). CONCLUSION: This study summarizes the largest sample of CNS tumor cases analyzed in Mexico and provides an important reference of the frequency of this tumor type in the country. This work will serve as a basis for conducting studies evaluating factors associated with the presence of CNS tumors and for identifying adequate public health interventions.