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Blessed with a salubrious climate, the city of Bengaluru over the past few decades has constantly witnessed thermal discomfort owing to several Urban Heat islands that have mushroomed within the city. The subsequent increase in builtup area, consequent loss of productive agricultural lands/green zones, encroachment of surface water bodies coupled with the ill-preparedness of decision makers to handle the demand for land have invariably crumbled the natural micro-climate of the city. In this present research, an attempt has been made to detect the distribution of Urban Heat Islands in Bengaluru City by conducting real-time survey at 100 observatories marked across the entire urban & rural locations; with thermohygrometers as per the W.M.O. guidelines. The study confirmed the violation of the Human Thermal Comfort Range in 9, 83, 98, 99, 98 and 80 observatories for the monitoring at 6 AM, 9 AM, 12 PM, 3 PM, 6 PM and 9 PM respectively.

Background  Spinal-cord stimulation (SCS) for relief of chronic neuropathic pain is well established. Objective  The inherent limitations with conventional percutaneous lead SCS are lead migration, positional variations in stimulation, as well as possible nonreplication of benefits after permanent SCS implantation, which were experienced during a positive trial period. To circumvent these limitations, we analyzed five consecutive cases of chronic intractable neuropathic pain who underwent direct SCS paddle lead placement during the trial period for pain relief. In addition, during the process of placing a permanent paddle lead, the impediment created by prior epidural scarring in such chronic patients can be obviated mechanically thereby increasing the efficacy of the procedure. Material and Methods  The demographic details, diagnosis, preoperative visual analogue scale score (VAS), and follow-up VAS were recorded. Surgical procedure consisted of a standard dorsal laminotomy followed by placement of permanent paddle leads. Results  All patients reported significant improvement in their VAS scores. Mean duration of follow-up was 23.6 months (9-35 months). Mean preoperative VAS was 9.4 and 1.4 at the last follow-up. No major complications were found. Conclusion  With careful patient selection and appropriate surgical strategy, it was possible to implant permanent paddle leads during SCS trial itself in our five patients thereby replicating and sustaining the trial period pain relief. We argue that this can be a new cost-effective and reliable technique for the placement of SCS leads achieving excellent and sustained pain relief., Competing Interests: Conflict of Interest None declared., (Asian Congress of Neurological Surgeons. This is an open access article published by Thieme under the terms of the Creative Commons Attribution-NonDerivative-NonCommercial License, permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commercial purposes, or adapted, remixed, transformed or built upon. ( https://creativecommons.org/licenses/by-nc-nd/4.0/ ).)

Advances in neuroimaging have increased the detection rate of small vestibular schwannomas (VSs, maximum diameter < 25 mm). Current management modalities include observation with serial imaging, stereotactic radiosurgery, and microsurgical resection. Selecting one approach over another invites speculation, and no standard management consensus has been established. Moreover, there is a distinct clinical heterogeneity among patients harboring small VSs, making standardization of management difficult. The aim of this article is to guide treating physicians toward the most plausible therapeutic option based on etiopathogenesis and the highest level of existing evidence specific to the different cohorts of hypothetical case scenarios. Hypothetical cases were created to represent 5 commonly encountered scenarios involving patients with sporadic unilateral small VSs, and the literature was reviewed with a focus on small VS. The authors extrapolated from the data to the hypothetical case scenarios, and based on the level of evidence, they discuss the most suitable patient-specific treatment strategies. They conclude that observation and imaging, stereotactic radiosurgery, and microsurgery are all important components of the management strategy. Each has unique advantages and disadvantages best suited to certain clinical scenarios. The treatment of small VS should always be tailored to the clinical, personal, and social requirements of an individual patient, and a rigid treatment protocol is not practical.

Objective Dorello's canal was first described by Gruber in 1859, and later by Dorello. Vail also described the anatomy of Dorello's canal. In the preceding century, Dorello's canal was clinically important, in understanding sixth nerve palsy and nowadays it is mostly important for skull base surgery. The understanding of the three dimensional anatomy, of this canal is very difficult to understand, and there is no simple explanation for its anatomy and its relationship with adjacent structures. We present a simple, Lego-like, presentation of Dorello's canal, in a stepwise manner. Materials and Methods Dorello's canal was dissected in five formalin-fixed cadaver specimens (10 sides). The craniotomy was performed, while preserving the neural and vascular structures associated with the canal. A 3D model was created, to explain the canal's anatomy. Results Using the petrous pyramid, the sixth nerve, the cavernous sinus, the trigeminal ganglion, the petorclival ligament and the posterior clinoid, the three-dimensional structure of Dorello's canal was defined. This simple representation aids in understanding the three dimensional relationship of Dorello's canal to its neighboring structures. Conclusion Dorello's canal with its three dimensional structure and relationship to its neighboring anatomical structures could be reconstructed using a few anatomical building blocks. This method simplifies the understanding of this complex anatomical structure, and could be used for teaching purposes for aspiring neurosurgeons, and anatomy students.

Objective The superior transvelar approach is used to access pathologies located in the fourth ventricle and brainstem. The surgical path is below the venous structures, through the superior medullary velum. Following splitting the tentorial edge, near the tentorial apex, the superior medullary velum is split in the cerebello-mesencephalic fissure. Using the supracerebellar infratentorial, transtentorial or parietal interhemispheric routes, the superior medullary velum is approached. Splitting this velum provides a detailed view of the fourth ventricle and its floor. Materials and Methods A total of 10 formalin-fixed specimens were dissected in a stepwise manner to simulate the superior transvelar approach to the fourth ventricle. The exposure gained the distance from the craniotomy site and the ease of access was assessed for each of the routes. We also present an illustrative case, operated by the senior author (AN). Results The superior transvelar approach provides access to the entire length of the fourth ventricle floor, from the aqueduct to the obex, when using the parietal interhemispheric route. In addition, this approach provides access to the entire width of the floor of the fourth ventricle; however, this requires retracting the superior cerebellar peduncle. Using the supracerebellar infratentorial route gives a limited exposure of the superior part of the fourth ventricle. The occipital interhemispheric route is a compromise between these two. Conclusion The superior transvelar approach to the fourth ventricle provides a route for approaching the fourth ventricle from above. This approach does not require opening the posterior fossa in the traditional way, and provides a reasonable alternative for accessing the superior fourth ventricle.

This study evaluated the outcomes, complications, and recurrence rates of posterior cranial fossa meningiomas. We retrospectively reviewed our surgical experience with 64 posterior cranial fossa meningiomas. Mean age was 56 years with a female preponderance (67.2%). Headache was the most common symptom. Retrosigmoid approach was the commonest surgical procedure (23.4%). The incidence of cranial nerve related complications was 28%. Postoperatively facial nerve weakness was observed in 11%. The incidence of cerebrospinal fluid leak was 4.6%. Gross total resection was achieved in 37 patients (58%). Sixteen patients (25%) with residual tumors underwent Gamma knife radiosurgery. Recurrence or tumor progression was observed in 12 patients (18.7%). Operative mortality was 3.1%. At their last follow-up, 93% of the cases achieved Glasgow Outcome Scale scores 4 or 5. Total excision is the ideal goal which can be achieved with meningiomas located in certain location, such as lateral convexity, but for other posterior fossa meningiomas the close proximity of critical structures is a major obstacle in achieving this goal. In practicality, a balance between good functional outcome and extent of resection is important for posterior cranial fossa meningiomas in proximity to critical structures.

Background and Purpose: The artery of Bernasconi and Cassinari is an important infraclinoid branch of the internal cerebral artery. It is of neuroendovascular relevance in view of its supply to complex lesions such as meningiomas and arteriovenous malformations in the tentorial and falcotentorial regions. The present microanatomic study attempts a morphometric elucidation of this slender but important branch of the meningohypophyseal trunk., Materials and Methods: The origin, course, dimensions, and related variations of the tentorial artery were studied in 10 formalin-fixed human cadaveric sides., Results: The tentorial artery originated from the meningohypophyseal trunk in all but 1 specimen, in which it arose directly from the intracavernous internal carotid artery. In 80% of specimens, it took origin as a single branch; as a bifurcation and trifurcation in 1 each. It was usually the terminal branch of the meningohypophyseal trunk (in 90%). In all, 5 distinct microvascular patterns were noted. The mean diameter of this artery was 0.7 mm (range, 0.3-0.8 mm; SD, ± 0.1 mm). The mean length was 15.4 mm (range, 9-23 mm; SD, ± 4.4 mm). Its mean distance from the origin of the meningohypophyseal trunk was 1.7 mm (range, 1.3-2.3 mm; SD, ± 0.4 mm). The mean distance from the free edge of the tentorium was 3.7 mm (range, 3-5 mm; SD, ± 0.7 mm)., Conclusions: The artery of Bernasconi and Cassinari is an important vascular conduit to myriad neoplasms and vascular malformations in the vicinity of the tentorium cerebelli. In this era of advanced microneurosurgical techniques and superselective endovascular interventions, morphometric knowledge of this artery is important for precise and safe management of these lesions.

Inadvertent injury to eustachian tube leading to cerebrospinal fluid rhinorrhea is a known complication associated with drilling of Glasscock's triangle to expose the horizontal petrous internal carotid artery (ICA) for management of difficult tumors (especially malignant) or aneurysms at the cranial base. Contrary to the usual approach, we hypothesize that a "medial-to-lateral" approach to Glasscock's triangle drilling will minimize eustachian tube injury. Four formalin-fixed human cadaveric heads were dissected, and underwent appropriate morphometric analysis; yielding a total of eight datasets. The diameter of the horizontal petrous ICA exposed was 4.7 ± 0.9 mm (range, 3.8 to 5.6 mm).The mean distance from the medial carotid wall midpoint to the medial-most point on the eustachian tube was 6.35 ± 0.58 mm (range, 5.4 to 7.1 mm), yielding a "safety zone" for eustachian tube, ranging 0.2 to 1.9 mm lateral to the lateral carotid wall. With the medial-to-lateral approach, the eustachian tube remained preserved in all the specimens. The results of our study provide a practical, consistent, and safe method of maximizing horizontal petrous carotid artery exposure while minimizing the eustachian tube injury.

We performed a trauma database analysis to identify the effect of concomitant cranial injuries on outcome in patients with fractures of the axis. We identified patients with axis fractures over a 14-year period. A binary outcome measure was used. Univariate and multiple logistic regression analysis were performed. There were 259 cases with axis fractures. Closed head injury was noted in 57% and skull base trauma in 14%. Death occurred in 17 cases (6%). Seventy-two percent had good outcome. Presence of abnormal computed tomography head findings, skull base fractures, and visceral injury was significantly associated with poor outcome. Skull base injury in association with fractures of the axis is a significant independent predictor of worse outcomes, irrespective of the severity of the head injury. We propose that presence of concomitant cranial and upper vertebral injuries require careful evaluation in view of the associated poor prognosis.

The "Agnes Fast" craniotomy is a fast and simple way of performing the pterional craniotomy while preserving the temporalis muscle, together with its fascia and bony attachment. Using this technique, the surgeon need not divide the temporalis muscle, separate it from its bony attachment, or perform an interfacial dissection. With a little practice, this craniotomy can be performed in less than 5 minutes and is highly recommended in emergent settings. The modified pterional craniotomy was performed in 10 cadaveric specimens, preserving the temporalis muscle with its attachment. An interfascial dissection was not performed while exposing the frontozygomatic process. The exposure gained, the length of the procedure, and the ease of application were recorded for all heads studied. In all heads studied, the Agnes Fast craniotomy was performed, with complete preservation of the temporalis muscle and its attachments. This procedure was performed quickly, with complete preservation of the fascial nerve and its branches. The muscle was put back in its natural place following the craniotomy. The Agnes Fast craniotomy offers a fast way of performing a pterional craniotomy while preserving the temporalis muscle, with its blood supply, neural innervation, bony attachment, and fascia intact. Replacing the muscle is also fast and simple and involves placement of two CranioFix (Aesculap, Inc., Center Valley, PA) holders to the bone, with no suture material. This approach does not limit the exposure gained and offers the same exposure as the "usual" pterional craniotomy.

Adding posterolateral orbitotomy to pterional craniotomy allows greater exposure of the anterolateral skull base. However, there is a paucity of literature quantifying the relative benefit of adding posterolateral orbitotomy for various surgical targets. Our study is a step to address this issue. We performed dissections of five cadaveric heads (10 sides). The anterior communicating artery (A-Com) complex, posterior chiasm (anterior third ventricular region), ipsilateral optic canal, and ipsilateral supraclinoid internal carotid artery (ICA) bifurcation were chosen as targets. A pterional craniotomy was performed and the targets were morphometrically analyzed. Subsequently, posterolateral orbitotomy was done and analysis repeated. The field of view and measurements quantifying the angle of attack were compared. Addition of orbitotomy to pterional craniotomy increased the angle of exposure to ICA bifurcation, anterior third ventricular region, and A-Com complex by average of 15%, 29%, and 50%, respectively. Our study shows the addition of a posterolateral orbitotomy to the pterional craniotomy improves the angle of attack to the anterior third ventricular region and the A-Com complex, thus supporting the use of orbitopterional craniotomy for suprasellar lesions extending into anteroinferior third ventricle and A-Com aneurysms that point superiorly/posteriorly.

Street dust samples were collected from three different localities (industrial, heavy traffic and rural) situated in the greater Delhi area of India. The samples analyzed for Cd, Zn, Pb, Ni, Cu, and Cr indicated remarkably high levels of Cr, Ni, and Cu in the industrial area, whilst Pb and Cd did not show any discernible variations between the three localities. A multivariate statistical approach (Principal Component Analysis) was used to define the possible origin of metals in dusts. The street dusts were sequentially extracted so that the solid pools of Cd, Zn, Pb, Ni, Cu, Cr could be partitioned into five operationally defined fractions viz. exchangeable, bound to carbonates, bound to Fe-Mn oxides, bound to organic matter and residual. Metal recoveries in sequential extractions were +/- 10% of the independently measured total metal concentrations. Cd was the only metal present appreciably (27.16%) in the exchangeable fraction and Cu was the only metal predominantly associated (44.26%) with organic fraction. Zn (45.64%) and Pb (28.26%) were present mainly in the Fe-Mn oxide fraction and the residual fraction was the most dominant solid phase pool of Cr (88.12%) and Ni (70.94%). Assuming that the mobility and bioavailability are related to the solubility of geochemical forms of the metals and decrease in order of extraction, the apparent mobility and potential metal bioavailability for these highly contaminated street dust samples is: Cd>Zn approximately equal Pb>Ni>Cu>Cr.

Recent studies on the mechanism by which the virion-associated RNA polymerase of vesicular stomatitis virus transcribes RNA have revealed several new biological features of general interest. The mode of synthesis of the 5'-terminal cap structure of the mRNAs, the sequential transcription of the genes and the presence of a transcribed "leader" RNA segment are properties which are either not shown by other viruses, or have not yet been described. These features are probably inter-related with the primary transcription process, which itself may be a useful model for future studies on mRNA biosynthesis in eukaryotic systems.