Pediatric upper airway dimensions using three-dimensional computed tomography imaging.

INTRODUCTION: Computed tomography- (CT) and magnetic resonance imaging (MRI)-based measurements have recently suggested that the narrowest dimension of the pediatric airway is the subglottic region. These data are contrary to the previously held tenets of a funnel- or conical-shaped airway. The current study evaluates airway volumes and shapes using three-dimensional CT images of the air way column in spontaneously breathing children. METHODS: The study included CT-based radiological images of the neck in children who required imaging unrelated to airway symptomatology. The children were evaluated during spontaneous ventilation during natural sleep or with sedation without airway devices in place. The three-dimensional images of the airway column were evaluated, volumes calculated, and comparisons made between the subglottic, cricoid, and tracheal volumes and shapes. RESULTS: The study cohort included 54 children, ranging in age from 2 months to 8 years. An increase in the airway volumes was observed from the subglottic (0.17 ± 0.06 mm3 ) to the cricoid (0.19 ± 0.06 mm3 ) to the tracheal regions (0.22 ± 0.07 mm3 ). The volumes of the subglottic, cricoid, and tracheal regions demonstrated a linear relationship with age. CONCLUSION: This study confirms recent studies demonstrating that the subglottic region not the cricoid is the narrowest part of the airway.

Pediatric Cervical Kyphosis: A Retrospective Multicenter Analysis and Literature Review.

Introduction: This study aims to investigate cervical kyphosis in children, which has gained increasing attention in recent years due to its higher incidence and its association with tumor surgeries, and to shed light on the unique anatomical and biomechanical differences between pediatric and adult populations regarding cervical sagittal alignment. Additionally, it explores the diverse causes and management approaches, which often pose significant challenges. Furthermore, this study presents the management outcomes from three spine centers in the Middle East. Methods: A retrospective analysis was conducted on patient records from 2009 to 2021 in three centers located in Saudi Arabia, Egypt, and Jordan. Demographic and clinical data were collected, imaging studies were reviewed, and various treatment modalities and their corresponding outcomes were documented and analyzed. Additionally, a literature review on pediatric cervical kyphosis and its management was performed. Results: Seventeen patients were included in this study. The average age at presentation was 11.9 years. Among the participants, 14 underwent surgical treatment, 1 was treated with Minerva orthosis, and 2 were observed. The mean follow-up period was 32.4 months. In surgically treated patients, a statistically significant higher degree of correction was achieved when combining anterior and posterior surgeries compared to performing standalone anterior or posterior surgery (P-value = 0.014). Conclusions: Although rare, pediatric cervical kyphosis is a significant condition within the spectrum of pediatric deformities and frequently occurs as a component of syndromes or as a result of iatrogenic factors. Neck pain and myelopathy are the most commonly observed symptoms. Thorough evaluation and complex surgical interventions are typically required for most cases.

"Brain Biopsy Revolution: Unveiling the Core Syringe Technique with Clinical Insights".

OBJECTIVES: Obtaining a definitive pathological diagnosis from brain tissue sampling was challenging due to the small, non-representative sample. This study introduced a novel syringe technique for brain biopsy aimed at enhancing diagnostic accuracy by obtaining core tissue samples that better represent the targeted tissue. METHODS: The ten patients with atypical brain lesions underwent the syringe biopsy. After meticulous preoperative planning with neuronavigation, a minimally invasive approach was used: a 3 cm skin incision and a 14 mm burr hole were created. A modified 3-cc syringe was used to create negative pressure and cannulate the brain tissue. The desired sample size (24 cm³) was obtained by controlling the syringe depth and withdrawal. Medical records were reviewed to assess sample analysis results and any complications RESULTS: The syringe technique successfully yielded adequate tissue samples in 9 out of 10 patients. In one case, the desired tissue could not be retrieved and required a microsurgical approach for removal. In all ten cases, a correct diagnosis was made without significant complications. CONCLUSION: The preliminary findings suggest that the syringe technique is both safe and effective for obtaining substantial volumes of brain tissue, facilitating accurate pathological evaluation in cases of complex neurological disorders.

Thalamic Tumors in a Pediatric Population: Surgical Outcomes and Utilization of High-Definition Fiber Tractography and the Fiber Tracking Technique.

OBJECTIVE: This study aimed to assess the operability of thalamic tumors since they are generally considered to be inoperable and to have poor outcomes. Advancements in neuroimaging, neuronavigational technology, and intraoperative neurophysiological monitoring allow accurate planning and safe resection. METHODS: Clinical data and reports of 10 pediatric patients with thalamic tumors were retrieved retrospectively. All 10 patients underwent surgical intervention. Diffusion tensor tractography (DTI) was used preoperatively to select the safest surgical route. Intraoperative MRI and postoperative MRI were used to evaluate the extent of resection. RESULTS: There were three gross total resections (GTRs), two subtotal resections (STRs), two partial resections (PRs), and three biopsies. All patients had unilateral thalamic tumors. Different surgical approaches were used according to the relationship with the internal capsule and corticospinal tract and according to the preoperative DTI. Five patients had pilocytic astrocytoma, two had diffuse pediatric-type high-grade glioma, one had ganglioglioma, one had pediatric-type diffuse low-grade glioma, and one had atypical teratoid rhabdoid tumor (ATRT). The outcomes of low-grade tumors were favorable, especially for those who underwent resection, and those of high-grade tumors were poor regardless of the extent of resection. CONCLUSION: Our review shows that surgical resection of thalamic tumors can be done safely and offers favorable outcomes for patients with low-grade tumors, even without adjuvant therapy. Our study provides further evidence for thalamic tumors operability and safe resection.

Conscious sedation for awake craniotomy in intra-operative magnetic resonance imaging operating theatre (IMRI OT) environment.

This technical report disrobes the first case in Intra-operative Magnatic Resonance Imaging operating theatre (iMRI OT) (BrainSuite), of Awake Craniotomy. The procedure was for frontal lobe glioma excision in 24 y. old man. He was scheduled to undergo eloquent cortex language mapping intra-operatively. He was motivated and was excited to see the operating theatre. He requested to take his photos while operated upon. The authors adapted conscious sedation technique with variable depth according to Ramsey's scale, in order to revert to awake state to perform the intended neurosurgical procedure. Patient tolerated the situation satisfactory and was cooperative till the finish without any event. We elicit in this report the special environment of iMRI OT for lengthy operation in pinned fixed patient having craniotomy. The text shows the special environment, its demands and its possible difficulties.

The topographic anatomy of the central artery: a neuronavigational-based study.

BACKGROUND/AIM: The central area of the brain, including the pre- and post-central gyri with their vascular structures, is one of the most crucial regions to preserve in neurosurgical intervention. The central sulcus is also a landmark of utmost importance for neurosurgeons. Although the arteries supplying the central region have been briefly described, their exact course has not been studied. The aim of the study is to establish the position and course of the central sulcus artery in relation to the central sulcus and its convolutions. METHODS: Computer-assisted three-dimensional (3-D) anatomical reconstructions of the central area and of the central sulcus artery were performed with the aid of neuronavigational software in 13 patients operated at the Montreal Neurological Institute (MNI). RESULTS: The central sulcus artery was coincident with the central sulcus and course(s) was almost similar on both hemispheres. CONCLUSIONS: The knowledge of the exact course of the central sulcus artery is of paramount importance in cases of lesions or epileptic foci involving the central area. 3-D reconstruction with neuronavigation has proven to be a reproducible and reliable technique to provide the surgeon with the necessary surgical topographic anatomy of the central sulcus artery and central area.

Meningioma Consistency: Correlation Between Magnetic Resonance Imaging Characteristics, Operative Findings, and Histopathological Features.

INTRODUCTION: Intracranial meningiomas account for 30% of all primary intracranial tumors. Surgical resection remains the mainstay of the treatment for meningiomas. The magnetic resonance of intracranial meningiomas has been largely discussed in many reports of the radiological and neurosurgical literature. To date, a few studies have been attempted to differentiate the tumor characteristics of meningiomas based on magnetic resonance imaging (MRI) studies. OBJECTIVE: The objective of the study is to evaluate the relationship between MRI signal characteristics of intracranial meningiomas and consistency of tumor using objective measures. MATERIALS AND METHODS: A prospective study included all the patients who were admitted for surgery with an MRI finding suggestive of meningioma. All patients were subjected to routine radiological investigations. Surgical resection was performed for patients eligible for surgery using cavitron ultrasonic aspirator (CUSA). The relationship and correlation between the radiological, intraoperative measurements and the histopathological diagnosis were studied. The tumor consistency was measured using mean CUSA level. Intensity on T2, fluid-attenuated inversion recovery (FLAIR), and diffusion-weighted imaging (DWI) was measured using circular regions of interest (ROI) on the MRI. Multiple ROIs were placed initially on the lesions avoiding the obvious blood vessels, if any, then on the brain cortex to avoid the vasogenic edema. The mean ROI (mROI) results from the lesion were subtracted from the mean ROI from the brain cortex for each lesion to achieve normalized ratio. The results of lesion mROI-cortex mROI were compared to the operative and histopathology results using Pearson's correlation test and linear regression test. RESULTS: The total number of patients was seventy. The mean age of the patients was 51 ± 14.8, with 72% of them being females and 28% males. There was a strong statistically significant (P = 0.046) and (P = 0.003) correlation between mean CUSA and FLAIR mROI difference or T2 mROI difference, respectively. On the other hand, there was an inversely proportional relationship between mean CUSA and FLAIR mROI difference and mean CUSA and T2 mROI difference. The value of the regression test (r) shows that there was a slight linear relationship between FLAIR mROI difference or T2 mROI difference and mean CUSA values, in which the mean CUSA value = 50.1 + (-0.088) × FLAIR mROI difference (r = -0.273, P = 0.046) or mean CUSA value = 50.8 + (-0.055) × T2 mROI difference (r = 0.4, P = 0.003). There was no statistical significance in the relation between CUSA values and tumor histological subtypes, DWI values, age, or gender. CONCLUSION: This study presents a new objective method to measure the consistency of intracranial meningiomas based on a simple algorithmic formula. Such information will aid in planning surgery and assessing the resectability of the tumor. To date, this is the first objective measurement of meningioma consistency based on MRI studies and objective intraoperative evaluation.

The role of periventricular nodular heterotopia in epileptogenesis.

A temporal resection in patients with periventricular nodular heterotopia (PNH) and intractable focal seizures yields poor results. To define the role of heterotopic grey matter tissue in epileptogenesis and to improve outcome, we performed stereoencephalography (SEEG) recordings in eight patients with uni- or bilateral PNH and intractable focal epilepsy. The SEEG studies aimed to evaluate the most epileptogenic areas and included the allo- and neocortex and at least one nodule of grey matter. Interictal spiking activity was found in ectopic grey matter in three patients, in the cortex overlying the nodules in five and in the mesial temporal structures in all. At least one heterotopion was involved at seizure onset in six patients, synchronous with the overlying neocortex or ipsilateral hippocampus. Two patients had their seizures originating in the mesial temporal structures only. Six patients had surgery and the resected areas included the seizure onset, with follow-up from 1 to 8 years. An amygdalo-hippocampectomy was performed in two (Engel class Id and III), an amygdalo-hippocampectomy plus removal of an adjacent heterotopion in two (class Ia), and a resection of two contiguous nodules plus a small rim of overlying occipital cortex in one patient (class Id). One patient with bilateral PNH had three adjacent nodules resected and an ipsilateral amygdalo-hippocampectomy resulting in a reduction of the number of seizures by 25-50%. The best predictor of surgical outcome is the presence of a focal epileptic generator; this generator may or may not include the PNH. Invasive recording is required in patients with PNH; it improves localization and is the key to better outcome.

Ultrasonic elastography using sector scan imaging and a radial compression.

Elastography is an imaging technique based on strain estimation in soft tissues under quasi-static compression. The stress is usually created by a compression plate, and the target is imaged by an ultrasonic linear array. This configuration is used for breast elastography, and has been investigated both theoretically and experimentally. Phenomena such as strain decay with tissue depth and strain concentrations have been reported. However in some in vivo situations, like prostate or blood vessels imaging, this set-up cannot be used. We propose a device to acquire in vivo elastograms of the prostate. The compression is applied by inflating a balloon that covers a transrectal sector probe. The 1D algorithm used to calculate the radial strain fails if the center of the imaging probe does not correspond to the center of the compressor. Therefore, experimental elastograms are calculated with a 2D algorithm that accounts for tangential displacements of the tissue. In this article, in order to gain a better understanding of the image formation process, the use of ultrasonic sector scans to image the radial compression of a target is investigated. Elastograms of homogeneous phantoms are presented, and compared with simulated images. Both show a strain decay with tissue depth. Then experimental and simulated elastograms of a phantom that contains a hard inclusion are presented, showing that strain concentrations occur as well. A method to compensate for strain decay and therefore to increase the contrast of the strain elastograms is proposed. It is expected that such information will help to interpret and possibly improve the elastograms obtained via radial compression.

Role of the O-arm and Computer-assisted Navigation of Safe Screw Fixation in Children with Traumatic Rotatory Atlantoaxial Subluxation.

STUDY DESIGN: A retrospective analysis of 7 patients with traumatic rotatory atlanto-axial subluxation. OVERVIEW OF LITERATURE: Cases of traumatic rotatory atlantoaxial subluxation in children are difficult to be stabilized. Surgical challenges include: narrow pedicles, medial vertebral arteries, vertebral artery anomalies, fractured pedicles or lateral masses, and fixed subluxation. The use of O-arm and computer-assisted navigation are still tested as aiding tools in such operative modalities. PURPOSE: Report of clinical series for evaluation of the safety of use of the O-arm and computed assisted-navigation in screw fixation in children with traumatic rotatory atlantoaxial subluxation. METHODS: In the present study, 7 cases of rotatory atlantoaxial traumatic subluxation were operated between December 2009 and March 2011. All patient-cases had undergone open reduction and instrumentation using atlas lateral mass and axis pedicle screws with intraoperative O-arm with computer-assisted navigation. RESULTS: All hardware was safely placed in the planned trajectories in all the 7 cases. Intraoperative O-arm and computer assisted-navigation were useful in securing neural and vascular tissues safety with tough-bony purchases of the hardware from the first and only trial of application with sufficient reduction of the subluxation. CONCLUSIONS: Successful surgery is possible with using the intraoperative O-arm and computer-assisted navigation in safe and proper placement of difficult atlas lateral mass and axis pedicle screws for rotatory atlantoaxial subluxation in children.