Microscope Magnification Research Articles

Anatomical Step-by-Step Dissection of Complex Skull Base Approaches for Trainees: Surgical Anatomy of the Middle Fossa Approaches and Anterior Petrosectomy, Surgical Principles, and Illustrative Cases.

Introduction The middle fossa (MF) approaches encompass a group of versatile surgical accesses to pathologies in the MF, internal auditory canal (IAC), and superomedial aspect of the posterior fossa. Although many descriptions of the MF approaches have been published, a practical surgical guide that allows an easy understanding for Skull Base trainees is needed. Methods Three formalin-fixed, colored-injected specimens were dissected under microscopic magnification (six sides). A MF craniotomy followed by IAC drilling was performed on three sides, and anterior petrosectomy (AP) was performed in the remaining three sides. The anatomical dissection was documented in stepwise three-dimensional photographic images. Following dissection, representative case applications were reviewed. Results The MF approach provides direct access to the MF structures and IAC. The AP provides excellent access to the superomedial aspect of the posterior fossa. Key common steps include: positioning and skin incision; scalp and muscle flaps; burr holes; craniotomy flap elevation; dural dissection along the petrous ridge; division of the middle meningeal artery; and exposure of the greater superficial petrosal nerve, tegmen tympani, and V3. Then, to approach the IAC: superior IAC drilling, and longitudinal dura opening. The area drilled in the AP approach forms a pentagon limited by the petrous internal carotid artery, cochlea, IAC, petrous ridge, and lateral border of V3. Conclusion The MF approaches are challenging. Operatively oriented skull base dissections provide a crucial foundation for learning these techniques. We describe comprehensive step-by-step approaches intended to develop familiarity in the cadaver laboratory and facilitate understanding of their potential for skull base disorders. Basic surgical principles are described to help in the operating room as well as illustrative cases.

Assessing the innervation of the dorsal wrist capsule using modified Sihler's staining.

The aim of this study was to assess the innervation of the dorsal articular capsule of the wrist using modified Sihler's staining. Thirty dorsal wrist capsules were collected from 15 donors (both sides) within 12 hours of death. All the capsules were collected in the same manner - using the dorsal incision. The specimens were stained according to the protocol of the modified Sihler's staining technique. The preserved capsules were analysed under 8-16× magnification of an optical microscope for the presence of major nerve trunks, their major and minor branches, and nerve connections. The range of innervation visualised was that the posterior interosseous nerve innervated approximately 60% of the central part; the remaining area was innervated by the dorsal sensory branch of the radial nerve and medial antebrachial cutaneous nerve. The constant findings were the branches departing from the ulnar side of the posterior interosseous nerve and from the radial side, with an exception seen in 2 cases. A communicans branch between the posterior interosseous nerve and medial antebrachial cutaneous nerve was seen in all the specimens. The posterior interosseous nerve innervation extended beyond the level of the carpometacarpal joints II-V. The modified Sihler's staining technique allows for transparent visibility of the nerves that innervate the dorsal wrist capsule. However, it does not allow as accurate assessment as does histological examination, especially regarding the evaluation of nerve endings. Nevertheless, this method provides a significantly larger area of nerve observation than is provided by histological examination.

Microsurgical anatomy of the amygdaloid body and its connections.

The amygdaloid body is a limbic nuclear complex characterized by connections with the thalamus, the brainstem and the neocortex. The recent advances in functional neurosurgery regarding the treatment of refractory epilepsy and several neuropsychiatric disorders renewed the interest in the study of its functional Neuroanatomy. In this scenario,we felt that a morphological study focused on the amygdaloid body anditsconnections could improve the understanding of thepossible implications in functional neurosurgery. With this purpose we performed a morfological study using nine formalin-fixed human hemispheres dissected under microscopicmagnification by using the fiber dissection technique originally described by Klingler. In our results the amygdaloid body presents two divergent projection systems named dorsal and ventral amygdalofugal pathways connecting the nuclear complex with the septum and the hypothalamus. Furthermore, the amygdaloid body is connected with the hippocampus through the amygdalo-hippocampal bundle, with the anterolateral temporal cortex through the amygdalo-temporalis fascicle, the anterior commissure and the temporo-pulvinar bundle of Arnold, with the insular cortex through the lateral olfactory stria, with the ambiens gyrus, the para-hippocampal gyrus and the basal forebrain through the cingulum, and with the frontal cortex through the uncinate fascicle. Finally, the amygdaloid body is connected with the brainstem through the medial forebrain bundle. Our description of the topographic anatomy of the amygdaloid body and its connections, hopefully representsa useful tool for clinicians and scientists, both in the scope of application and speculation.

Acute systemic LPS-exposure impairs perivascular CSF distribution in mice

BackgroundThe exchange of cerebrospinal (CSF) and interstitial fluid is believed to be vital for waste clearance in the brain. The sleep-dependent glymphatic system, which is comprised of perivascular flow of CSF and is largely dependent on arterial pulsatility and astrocytic aquaporin-4 (AQP4) expression, facilitates much of this brain clearance. During the last decade, several observations have indicated that impaired glymphatic function goes hand in hand with neurodegenerative diseases. Since pathologies of the brain carry inflammatory components, we wanted to know how acute inflammation, e.g., with lipopolysaccharide (LPS) injections, would affect the glymphatic system. In this study, we aim to measure the effect of LPS on perivascular CSF distribution as a measure of glymphatic function.MethodsThree hours after injection of LPS (1 mg/kg i.p.), C57bl/6 mice were (1) imaged for two CSF tracers, injected into cisterna magna, (2) transcardially perfused with buffer, or (3) used for physiological readouts. Tracer flow was imaged using a low magnification microscope on fixed brains, as well as using vibratome-cut slices for measuring tracer penetration in the brain. Cytokines, glial, and BBB-permeability markers were measured with ELISAs, Western blots, and immunohistochemistry. Cerebral blood flow was approximated using laser Doppler flowmetry, respiration and heart rate with a surgical monitor, and AQP4-polarization was quantified using confocal microscopy of immunolabeled brain sections.ResultsLPS-injections significantly lowered perivascular CSF tracer flow and penetration into the parenchyma. No differences in AQP4 polarization, cytokines, astroglial and BBB markers, cerebral blood flow, or respiration were detected in LPS-injected mice, although LPS did elevate cortical Iba1+ area and heart rate.ConclusionsThis study reports another physiological response after acute exposure to the bacterial endotoxin LPS, namely the statistically significant decrease in perivascular distribution of CSF. These observations may benefit our understanding of the role of systemic inflammation in brain clearance.

Endodontic treatment of a hypertaurodont mandibular second molar with C-shaped canal: A case report

Taurodontism is a variation in tooth anatomy characterized by an enlarged pulp chamber with hypertaurodont being its most severe presentation. The complexity of endodontic treatment of hypertaurodont tooth may be compounded by coexistent C-shaped canal anatomy. A 26-year-old patient reported with spontaneous and lingering pain due to a deep carious lesion in the right mandibular second molar. Clinical and radiographic examinations were done. A diagnosis of symptomatic irreversible pulpitis with symptomatic apical periodontitis in a hypertaurodont with an associated C-shaped canal configuration was made. The cone-beam computed tomography image guide together with microscopic magnification was utilized to negotiate, clean, and shape the root canal system. The isthmus of the C-shaped canal was prepared with ultrasonic tips, while Endoactivator sonic irrigant activation was employed for effectively disinfecting of the uninstrumentable intercommunications, apical splits, and ramifications. The apical root canals were obturated by lateral condensation technique, while warm vertical compaction of gutta-percha was utilized to fill the remaining pulp chamber. A 1 year follow-up of the case reveals a functional tooth with no signs of periapical infection, indicating a successful treatment outcome.

Nfertilite Tedavisinde TESE Başarısını Etkileyen Faktörler: Tek Merkez Deneyimi Ön Sonuçları

Objective: Today, infertility is a health problem with increasing treatment seeking. Testicular sperm extraction (TESE) is the only possible procedure to offer genetic parenting to men with nonobstructive azoospermia (NOA). Our aim in this study is to present our clinical experiences that affect the success of sperm retrieval in men with NOA in the light of the literature. Materials and Methods: In our study, patients who underwent TESE with a diagnosis of NOA between 2017-2020 were retrospectively analyzed. According to the TESE procedure; the patients were divided into two groups as conventional TESE and TESE performed under microscopic magnification (micro-TESE). Medical histories, hormone values, and physical examination findings of all patients were recorded. Results: Our micro-TESE success rate was found to be 100%. A positive correlation (rho 0.714, p = 0.009) was found between the factors affecting sperm retrieval , and the application of micro-TESE, and a negative correlation was detected with FSH levels (rho -0.759, p = 0.004). Conclusion: The success of sperm retrieval increases with the micro-TESE procedure. As FSH levels increase, sperm retrieval success rates decrease.

Morphology and histology of paryphasmata and hemibaculum of Varanus salvator based on sexual maturity.

Background:Varanus salvator is one of the reptiles being hunted by human beings for several purposes, including traditional medicine. The studies about reproductive biology aspects were limited. Aim:This study aimed to determine the morphology, histology, and histometry of V. salvator paryphasmata and hemibaculum based on Snout-Vent Length (SVL) as an indicator of sexual maturity.Methods:This study examined 18 pairs of hemipenis of V. salvator with SVL more and less than 40 cm in equal number. Paryphasmata and hemibaculum parts were observed visually and micro-sliced, then stained with Hematoxylin-Eosin (HE). The histological observation was conducted under a 40×, 100×, and 400× magnification of a light microscope. The histometry of the paryphasmata was examined using 13 Megapixels Coolpad and OptiLab Plus for microscopic pictures. The chondrocyte cell area was measured using the Optilab Plus and Image Raster three applications.Results:The sizes of glans of hemipenis, paryphasmata, and hemibaculum increased according to the increasing of SVL. The average paryphasmata row number, epidermis, and loose connective tissue thickness were not significantly different (p > 0.05). However, dense connective tissue was thicker (p < 0.05), which corresponds to SVL. Hemibaculum was composed of fibrous and hyaline cartilage characterized by chondrocyte cells. The SVL also affects (p < 0.05) the ossification of hyaline in hemipenis, while the chondrocyte cell area followed the equation −1.87E7 + 7.09E5* SVL.Conclusion:The SVL size of V. salvator affects the paryphasmata, hemibaculum, thickness of dense connective tissue of paryphasmata, and the area of chondrocyte cells.

Physical and chemical characterization of African catfish smoked sausage with different liquid smoke concentrations and immersion durations

Product diversification is needed to increase selling and marketing prices. One of them is the African catfish sausage product. Liquid smoke has been used commercially by the food industry. This study aimed to determine the physical and chemical properties of smoked African catfish after adding different concentrations of liquid smoke and immersion duration. The chemical analysis measured the levels of protein, fat, and phenol. The results showed that sausage with a concentration of 20% liquid and soaking for 30 minutes was the best treatment with a protein content of 43.8 ± 0.34%, a fat of 12.33 ± 0.61%, and phenol 292.74 ppm. Determination of the compound using GC-MS found that the most dominant compound in the smokeless sausage was 2-hexanone, 3,3 dimethyl with a relative concentration of 32.42%. The dominant compound in the besttreated sausage was Furan, tetrahydro-2,2-dimethyl- with a relative concentration of 19%. Liquid smoke penetration is clearly visible in the microstructure of smoked sausages, both in the best-treated smoked sausages and commercial sausages. Scanning Electron Microscope (SEM) magnification of 2.500x shows that the best emulsified smoked sausages have a flatter structure, smaller droplets, and are more refined than smokeless sausages or commercial smoked sausages.

Morphological features of non-parenchymal liver cells of full-term stillbirths from HIV-mono-infected mothers.

Fifty-one liver tissue biopsies offull-term stillbirths from HIV-mono-infected mothers were investigated. All morphometric indices ofnon-parenchymal liver cells were calculated using theAvtandilov microscopic morphometric grid, which consisted of100 equidistant points. It was inserted into themicroscope ocular tube with atotal × 200 microscope magnification. Thenumber ofpoints that were found in thecorresponding types ofnon-parenchymal liver cells determined by immunohistochemistry was calculated. In each case, 10 random microscopic areas were selected and then all data were obtained, calculated and presented as percentages. Morphometric indices ofnon-parenchymal liver cells: Kupffer cells - 28.3±2.9% [control - 21.2 ±2.5], hepatic stellate cells - 14.1 ±1.4% [control - 9.8 ±1.2], LAL (liver-associated lymphocytes): CD4 - 29.2 ±2.2% [control - 43.3 ±4.9], CD8 - 25.3 ±1.9% [control - 23.1 ±1.7], dendritic cells - 3.9 ±0.3% [control - 2.6 ±0.3]. It was established that at thetime ofthebirth ofchildren from HIV-mono-infected mothers theKupffer cells showed signs oftheir proliferation and liver-associated CD4 lymphocytes showed signs oftheir reduction; hepatic stellate cells showed signs oftheir proliferation and hyperactivation; dendritic liver cells showed signs oftheir proliferation.

The morphological specifics of the stromal and parenchymal liver components of 6-12-months old children from hiv-mono-infected mothers

To determine the morphological specifics of the stromal and parenchymal liver components of 6-12-months old children from HIV-mono-infected mothers. Materials and methods. The morphometric investigation included 87 liver tissue biopsies of 6-12-months old dead children from HIV-mono-infected mothers. All morphometric parameters of the parenchymal and stromal liver components were calculated using the Avtandilov`s microscopic morphometric grid, which was consisted of 100 equidistant points. It was inserted into the microscope`s ocular tube with a total × 200 microscope magnification. The number of points that were found on the corresponding types of parenchymal and stromal liver components was calculated. In every case, it was selected 10 random microscopic areas and then all data were obtained, calculated and presented as percentages. Results. Morphometric parameters of hepatocytes: mononuclear hepatocytes – 90.2±7.6 % [control – 93.5±7.1], two-nuclear hepatocytes – 9.8±1.2 % [control – 6.5±1.2], TMHC (two-/mononuclear hepatocytes coefficient) – 0.10±0.02 [control – 0.06±0.01], hepatocytes with fat vacuoles – 19.6±2.1 % [control – 0.5±0.2]. Parenchymal and stromal liver components: parenchyma – 56.1±3.3 % [control – 74.2±4.3], stroma (including blood vessels and bile ducts) – 43.9±3.7 % [control – 25.8±2.6], SPI (stroma/parenchyma index) – 0.78±0.02 [control – 0.34±0.01]. Morphometric parameters of all of the liver components: hepatocytes – 56.1±3.3 % [control – 74.2±4.3], portal tracts – 26.4±2.1 % [control – 3.1±0.6], central veins – 8.1±1.2 % [control – 9.3±1.4], sinusoids – 7.3±1.2 % [control – 10.5±1.3], bile ducts – 2.1±0.1 % [control – 2.9±0.2]. Expression level parameters: fibronectin – 73.2±4.2 % [control – 17.3±2.5], collagen type I – 15.9±1.2 % [control – 9.7±1.9], collagen type III – 20.1±2.6 % [control – 10.1±0.9], collagen type IV – 7.3±0.2 % [control – 5.9±0.2]. Conclusions. It was established, that in the liver of 6-12-months old children from HIV-mono-infected mothers, the parenchymal component of the liver showed the signs of its significant reduction, increase of regenerative activity of hepatocytes, and fatty degeneration of hepatocytes with a certain sign of reactive steatohepatitis. Also, it was established, that the stromal component of the liver of children from HIV-infected mothers showed the signs of its progressive proliferation and collagenization due to increased production and accumulation of fibronectin, type I, type III collagens in the stroma of portal tracts and newly formed septa, and the signs of hepatic sinusoid capillarization due to type IV collagen accumulation in the space of Disse of the hepatic sinusoids.

What Are the Useful Tips for Opening the Sylvian and Interhemispheric Fissures with Minimal Blood Loss

The transsylvian approach(TSA)and interhemispheric approach(IHA)are two basic and important surgical approaches for the treatment of cerebral aneurysms. The TSA is usually the first choice for treating middle cerebral artery aneurysms but is sometimes used for treating even anterior communicating artery, internal carotid artery, and basilar artery aneurysms. In contrast, the IHA is usually the first choice for treating anterior communicating artery and distal anterior cerebral artery aneurysms. Young inexperienced neurosurgeons may find these approaches difficult to perform without blood loss. Therefore, the aim of this study was to provide useful tips regarding hemostasis, brain retraction, and intraoperative microscope magnification for performing the TSA and IHA without blood loss by using intraoperative photography.

Robust Magnification Independent Colon Biopsy Grading System over Multiple Data Sources

Automated grading of colon biopsy images across all magnifications is challenging because of tailored segmentation and dependent features on each magnification. This work presents a novel approach of robust magnification-independent colon cancer grading framework to distinguish colon biopsy images into four classes: normal, well, moderate, and poor. The contribution of this research is to develop a magnification invariant hybrid feature set comprising cartoon feature, Gabor wavelet, wavelet moments, HSV histogram, color auto-correlogram, color moments, and morphological features that can be used to characterize different grades. Besides, the classifier is modeled as a multiclass structure with six binary class Bayesian optimized random forest (BO-RF) classifiers. This study uses four datasets (two collected from Indian hospitals—Ishita Pathology Center (IPC) of 4X, 10X, and 40X and Aster Medcity (AMC) of 10X, 20X, and 40X—two benchmark datasets—gland segmentation (GlaS) of 20X and IMEDIATREAT of 10X) comprising multiple microscope magnifications. Experimental results demonstrate that the proposed method outperforms the other methods used for colon cancer grading in terms of accuracy (97.25%-IPC, 94.40%-AMC, 97.58%-GlaS, 99.16%-Imediatreat), sensitivity (0.9725-IPC, 0.9440-AMC, 0.9807-GlaS, 0.9923-Imediatreat), specificity (0.9908-IPC, 0.9813-AMC, 0.9907-GlaS, 0.9971-Imediatreat) and F-score (0.9725-IPC, 0.9441-AMC, 0.9780-GlaS, 0.9923-Imediatreat). The generalizability of the model to any magnified input image is validated by training in one dataset and testing in another dataset, highlighting strong concordance in multiclass classification and evidencing its effective use in the first level of automatic biopsy grading and second opinion.

Chromosomal aberrations induced by cassava industrial effluent using Allium Cepa assay

This study assessed the heavy metal compositions and chromosome aberrations induced by cassava industrial effluent using Allium cepa meristem assay. Effluent collected at the point of discharge from the cassava processing factory located at Lokoja, Kogi State Nigeria was analyzed for quantity of Cadmium (Cd), Chromium (Cr), Copper (Cu), Manganese (Mn), Iron (Fe), Nickel Ni, Cobalt (Co) and Lead (Pb) using Atomic Absorption Spectrophotometer method. Onion (Allium cepa) roots were allowed to grow in beakers containing different concentrations of cassava industrial effluent (i.e. 25%, 50%, 75% and 100%) and the control for 24 hours. Harvesting of the tips for chromosome observations was carried out between 8:00 to 9:00am West Africa Time. Data pooled under X400 magnification of the light microscope for mitotic phases and chromosome aberrations were analyzed using Analysis of Variance (ANOVA) while means with significant difference across concentrations were separated using Duncan Multiple Range Test (DMRT). The results revealed that only Cadmium (Cd) and Lead (Pb) concentrations in the effluent were higher than the minimum values recommended by World Health Organization. The effluent also produce binucleate cells, variant chromosomes, C-mitosis, vacuolated cells, tripolar anaphase and anaphase bridge which suggests the mutagenic and cytotoxic activities of the industrial effluent. The decrease in the Mitotic Indices (MI) of effluent-treated root cells compared to the control indicates mito-depressive ability of the effluent at every concentration. Regular monitoring of industries for compliance to treatment of effluent before releasing them into the environment is recommended.

Intra-Arterial Infusion of Magnetic Nanoparticle-Based Theragnostic Agent to Treat Colorectal Cancer Liver Implants in Rats

Introduction: Nowadays, surgical excision remains the gold standard to treat liver metastases of colorectal cancer (CRCLM). However, as more than 50% of patients are not eligible for surgery, other alternatives such as percutaneous or intravascular interventional therapies (thermal ablation, chemoembolization, or radioembolization), are quite relevant. Recently, the use of magnetic nanoparticles (MNPs) has been suggested as an adjuvant for these therapies, as they could increase their necrotising effect on the tumour while reducing doses and exposure times of thermal therapies. To investigate the potential curative effect of these compounds, animal models are needed, both for the development of experimental interventional procedures and for MNPs toxicity and distribution assessment. Herein, we describe both an experimental infusion procedure in CRCLM-bearing rats and analytical and histological methods to evaluate MNPs deposits in the tissue. Methods: Eighteen male WAG/RijHsd rats were subjected to intrahepatic injection of 250,000 colorectal cancer cells. Twenty-eight days later, half of the tumour-positive animals (n = 6) were administered with MNPs while the other half (n = 6) did not receive any injection and were used as control. Under microscope magnification, the splenic artery was carefully and completely dissected, and a catheter was inserted through the splenic artery to the common hepatic artery where 1 mL MNPs suspension was administered in 5 min; then STIR, DP*, and T2 MRI sequences were obtained (and signal intensity measured) and both tumour and liver tissue samples were collected for elemental and histological analyses. Conclusion: Our method for selective administration of MNPs is reproducible and well-tolerated and it fairly mimics the approach used in clinical practice when intravascular interventional therapies are applied.

Remoção de retentor intrarradicular com auxílio de microscopia: relato de caso

O objetivo deste estudo é relatar um caso clínico de remoção de um pino pré-fabricado rosqueável metálico com auxílio de magnificação por microscópio e uso de ultrassom. Paciente de 47 anos, gênero feminino, compareceu à clínica de odontologia queixando-se da insatisfação com seu sorriso. Durante a anamnese observou-se que as restaurações nos dentes 44, 45, 46 e 47 apresentavam-se insatisfatórias. Nos exames radiográficos foi possível observar lesão periapical nos dentes 44 e 47, presença de tratamentos endodônticos insatisfatórios no 44, 45, 46 e 47, e a presença de retentores intrarradiculares metálicos em todos os dentes citados. A partir dos exames, planejou-se a remoção do pino pré-fabricado do dente 45. O processo de remoção iniciou-se com isolamento absoluto e remoção do material restaurador, em seguida, com auxílio de um microscópio óptico para magnificação do campo, foi realizada a técnica de sistema integrado e simultâneo de ultrassom, em que utiliza-se duas pontas de ultrassom em vibrações opostas sobre o retentor. Após sequências de aplicação da técnica houve fratura da película de cimento e o pino foi removido. Assim, a associação da magnificação proporcionada pelo microscópio e a vibração do ultrassom foram resolutivos, pois ofereceram melhor acuidade visual e segurança no procedimento.

The role of ozonated Aloe vera oil in full-thickness skin defects: Macrophage count and epithelization length parameter

Background: Aloe vera has been reported to enhance keratinocyte proliferation and migration, and thereby accelerate wound healing. Ozone therapy is an alternative medicine with disinfecting properties and strong oxidative stress induction capacity. This study aimed to evaluate the effect of Aloe vera oil provided with different dosages of ozone in accelerating the healing rate comparing two-phases; inflammation (day 3) and proliferation (day 7) of full-thickness defect wounds in Sprague Dawley rats as an adjuvant treatment based on macrophage count and new epithelialization length. Methods: We conducted a study using a post-test only control group design, where a total of 50 Sprague Dawley rats were randomized into ten groups. Two control groups were administered Aloe vera oil (P1, P6), while gentamicin ointment was used in the other control group (P2, P7). Ozonated Aloe vera oil dose was used: 600 mg/ml (P3,P8), 1200 mg/ml (P4,P9), and 1800 mg/ml (P5,P10). Groups P1, P2, P3, P4, P5 were terminated on the 3rd day, while P6, P7, P8, P9, P10 were evaluated on the 7th day. Macrophage counts were assessed using a 100x magnification microscope, through hematoxylin-eosin (HE) staining, and paraffin block with Masson trichrome staining was used to measure the new epithelialization length. Results: There were significant differences in the macrophage count on day three between the group-administered gentamicin (P2) and 1800 mg/ml ozonated Aloe vera oil (P5) (79.96;131.96, p&lt;0,05). The new epithelialization length significantly increased in the group provided with wound treatment up to day 7, using 1800 mg/ml ozonated Aloe vera oil (P10), compared to non-ozonated Aloe vera (P6) and the gentamicin therapy (P7) (1160.88 µm; 1367.64; 2451.40 μm, p&lt;0,05). Conclusions: The application of ozonated Aloe vera oil to full-thickness skin defects in Sprague Dawley rats resulted in a higher macrophage count and longer new epithelialization length than in controls.

Effect of vascularized periosteum on revitalization of massive bone isografts: An experimental study in a rabbit model.

In the last years, limb salvage has become the gold standard treatment over amputation. Today, 90% of extremity osteogenic sarcomas can be treated with limb salvage surgery. However, these reconstructions are not exempt from complications. Massive allografts have been associated to high risk of nonunion (12-57%), fracture (7-30%) and infection (5-21%). Association of vascularized periosteum flap to a massive bone allograft (MBA) has shown to halve the average time of allograft union in clinical series, even compared to vascularized fibular flap. Creeping substitution process has been reported in massive allograft when periosteum flap was associated. However, we have little data about whether it results into allograft revitalization. We hypothesize that the association of a periosteum flap to a bone isograft promotes isograft revitalization, defined as the colonization of the devitalized bone by new-form vessels and viable osteocytes, turning it vital. Forty-four New Zealand white male rabbits underwent a 10 mm segmental radial bone defect. In 24 rabbits the bone excision included the periosteum (controls); in 20 rabbits (periosteum group) bone excision was performed carefully detaching periosteum in order to preserve it. Cryopreserved bone isograft from another rabbit was trimmed and placed to the defect gap and was fixed with a retrograde intramedullar 0.6 mm Kirschner wire. Rabbits were randomized and distributed in 3 subgroups depending on the follow-up (control group: 5 rabbits in 5-week follow up group, 8 rabbits in 10-week follow-up group, 7 rabbits in 20-week follow-up group; periosteum group: 5 rabbits in 5-week follow up group, 7 rabbits in 10-week follow-up group, 7 rabbits in 20-week follow-up group). Fluoroscopic images of rabbit forelimb were taken after sacrifice to address union. Each specimen was blindly evaluated in optical microscope (magnification, ×4) after hematoxylin and eosin staining to qualitative record: presence of new vessels and osteocytes in bone graft lacunae (yes/no) to address revitalization, presence of callus (yes/no) and woven bone and cartilage tissue area (mm2 ) to address remodeling (osteoclast resorption of old bone and substitution by osteoblastic new bone formation). No isograft revitalization occurred in any group, but it was observed bone graft resorption and substitution by new-formed bone in periosteum group. This phenomenon was accelerated in 5-week periosteum group (control group: 49.5 ± 9.6 mm2 vs. periosteum group: 34.9 ± 10.4 mm2 ; p = .07). Remodeled lamellar bone was observed in both 20-week groups (control group: 6.1 ± 6.3 mm2 vs. periosteum group: 5.8 ± 3.0 mm2 , p = .67). Periosteum group showed complete integration and graft substitution, whereas devitalized osteons were still observed in 20-week controls. All periosteum group samples showed radiographic union through a bone callus, whereas controls showed nonunion in eight specimens (Union rate: control group 60% vs. periosteum group 100%, p = .003). Association of vascularized periosteum to a massive bone isograft has shown to accelerate bone graft substitution into a newly formed bone, thus, no bone graft revitalization occurs.

The influence of a selected desensitizer on marginal microleakage of a class V composite restoration subjected to thermocycles: an in vitro study.

Dentin hypersensitivity is a painful clinical condition. The frequency of its occurrence varies from 8 to 57%, depending on tested group and different methods of investigations. Recommended desensitizing agents have different mechanism of action and effectiveness. We are still looking for solutions that will improve their effectiveness and simultaneously allow for wider use of e.g. as a base material, counteracting postoperative hypersensitivity, reducing marginal microleakage. The aim of the study was to assess the effect of a selected desensitizing agent occluding dentin tubules with calcium hydroxyapatite on marginal microleakage formation of a class V composite restorations subjected to thermocycles. In study it was used 40 molars and premolars, which were alternately assigned into two groups. In both groups standardized cavities were prepared. In the study group (study group - SG) before application of bonding agent Teethmate Desensitizer (f. Kuraray, Noritake Dental Inc., Okayama, Japan) was used. In the control group (control group - CG) OptiBond All-in-one (f. Kerr, Bioggio, Switzerland) bonding agent was used and cavities were filled using composite material Gradia Direct (f. GC Europe N.V., Leuven, Belgium). After storage in saline, teeth were subjected to 600 thermocycles, passive dye penetration test was done, teeth were cut in the area of filling, according to its long axis. Under light microscope magnification value of microleakage was measured and marginal microleakage rate (M) was counted. The results of the tests were statistically analyzed using the package STATISTICA 12.0 (StatSoft, USA). The average value of M for the SG group was 0.46 (min 0.05, max 0.76, SD 0.226) and for CG was 0.22 (min 0, max 0.74, SD 0.235). The differences between M values were statistically significant (p = 0.0094). A reduction in the number of retention sites for the bonding system, facilitates the formation of microleakage in the experimental conditions and reduces the degree of adhesion of the composite material to the hard tissues of the tooth.

Double-Nerve Transfer to the Axillary Nerve in Traumatic Upper Trunk Brachial Plexus Injuries Using an Axillary Approach: Anatomical Description and Preliminary Case Series

Restoration of shoulder external rotation remains challenging in patients with C5/C6 brachial plexus injuries (BPI). To describe a double-nerve transfer to the axillary nerve (AN), targeting both its anterior and posterior motor branches, through an axillary route. A total of 10 fresh-frozen cadaveric brachial plexuses were dissected. Using an axillary approach, the infraclavicular brachial plexus terminal branches were exposed, including the axillary, ulnar, and radial nerves. Under microscopic magnification, the triceps long head motor branch (TLHMB), anteromedial fascicles of the ulnar nerve (UF), the anterior motor branch of the axillary nerve (AAMB), and the teres minor motor branch (TMMB) were dissected and transected to simulate 2 nerve transfers, THLMB-AAMB and UF-TMMB. Several anatomical criteria were assessed, including the overlaps between fascicles when placed side-by-side. Six patients with C5/C6 BPI were then operated on using this technique. TLHMB-AAMB and UF-TMMB transfers could be simulated in all specimens, with mean overlaps of 37.1 mm and 6.5 mm, respectively. After a mean follow-up of 23 mo, all patients had recovered grade-3 strength or more in the deltoid and teres minor muscles. Mean active shoulder flexion, abduction, and external rotation with the arm 90° abducted were of 128°, 117°, and 51°, respectively. No postoperative motor deficit was found in the UF territory. A double-nerve transfer, based on radial and ulnar fascicles, appears to be an adequate option to reanimate both motor branches of the AN, providing satisfactory shoulder active elevations and external rotation in C5/C6 BPI patients.

Surgical Anatomy of the Labyrinthine and Subarcuate Arteries and Clinical Implications

To study the surgical anatomy of the labyrinthine artery (LA) and the subarcuate artery (SA), their anatomic relationships, and clinical implications, as injury of the LA can result in hearing loss. Ten formalin-fixed, latex-colored specimens were studied (20 sides). After retrosigmoid craniotomy and neurovascular dissection under microscopic magnification, 4-mm 0° and 30° endoscopic lenses were used to improve visualization. Results were statistically analyzed. The LA was a constant artery that followed the vestibulocochlear nerve into the internal auditory canal. The SA was an inconstant artery that ended in the dura mater around the subarcuate fossa in 35% of cases. The LA originated from the anterior inferior cerebellar artery in 89.3% of specimens and from the basilar artery in 10.7% of specimens. The SA branched off from the anterior inferior cerebellar artery when present. The origin of the LA was inferomedial to the vestibulocochlear nerve in most cases (71.4%), whereas the SA was usually lateral (70%). The distal portion of the LA was inferomedial to the vestibulocochlear nerve in 71.4% of cases. The distal portion of the SA was superolateral to the nerve in all cases (P < 0.00001). Knowledge of the different trajectory and anatomic relationship of the LA and the SA with the vestibulocochlear nerve is of paramount importance to differentiate them during surgery. The LA is usually inferomedial to the vestibulocochlear nerve at its distal and proximal aspects, whereas the SA usually originates lateral and ends superolateral to the nerve.