Bipolar, high-voltage, long-duration pulsed radiofrequency ablation of the Gasserian ganglion for the treatment of trigeminal neuralgia in a patient with a cardiac implantable electronic device: illustrative case

BACKGROUND

One of the common methods of treating trigeminal neuralgia (TN) nowadays is radiofrequency therapy. However, it has serious limitations in patients with a cardiac pacemaker because of electromagnetic interference. Therefore, it is crucial to select optimal radiofrequency ablation parameters to make this procedure safe with favorable outcomes for such patients.

OBSERVATIONS

In this study, the authors present a case of a 70-year-old man with a history of cardiac pacemaker dependency and previous microvascular decompression with complaints of severe, constant facial pain. After reprogramming the cardiac implantable electronic device (CIED), the authors performed bipolar, high-voltage, long-duration pulsed radiofrequency therapy (PRFT) of the Gasserian ganglion under electrocardiography and pulse rate control in the pre-, intra-, and postoperative periods. There were no cardiovascular or neurological complications after PRFT. The patient reported relief of pain after the procedure, and at the 9-month follow-up, he was pain-free.

LESSONS

This clinical case demonstrates that the use of bipolar, high-voltage PRFT for TN treatment in patients with a CIED can be safe and effective, provided that the rules and pacemaker instructions are followed. It is necessary to use ablative treatment with caution and to guide the patient in collaboration with a cardiac surgeon and an anesthesiologist resuscitator.

Exoscopic removal of the fourth ventricle choroid plexus papilloma with use of a midline suboccipital osteoplastic craniotomy

Choroid plexus papillomas are relatively rare vascular tumors. In this video, the authors present a pediatric patient who underwent exoscopic removal of the fourth ventricle choroid plexus papilloma with the use of a midline suboccipital osteoplastic craniotomy. The exoscope in the fourth ventricle lesion helps to improve visualization in all directions, with the surgeon being able to maintain a comfortable position throughout the procedure. In addition, the midline suboccipital osteoplastic craniotomy helps to reduce the potential risks of complications, in particular, CSF leak and craniovertebral junction instability. The video can be found here: https://stream.cadmore.media/r10.3171/2023.10.FOCVID23106.

Anatomical Justification of Extradural Resection of the Anterior Clinoid Process

Objective  The study aimed to provide neuroanatomical justification of the extradural resection of the anterior clinoid process (ACP). Material and Method  Using a cross-sectional study design, 47 cranial computed tomography (CT) scans were examined. There were 31 (65.96%) females aged 28 to 79 years. The measured dimensions were ACP length and width, and optic strut (OS) width. Index (i acp ) was measured as the ratio of ACP width to ACP length. The ACP volume and working operating field (WOF) volume were measured using Syngo.via Siemens program. The percentage expansion of WOF after removal of the ACP was estimated on 5 fixed human cadaver heads with the exoscope VITOM 3D. The possibilities of the combined approach were demonstrated in a clinical case. Results  The mean ACP lengths were 11.31 ± 2.76 and 11.54 ± 2.86 mm, on the right and left, respectively. The mean ACP widths were 7.70 ± 1.66 and 7.64 ± 1.67 mm, on the right and left, respectively. Average i acp was 0.67 (minimum 0.45; maximum 0.90). The width of the OS varied in the range from 1.37 to 4.75 mm. The average volume of right ACP was 0.71 ± 0.16 cm 3 , right WOF was 3.26 ± 0.74 cm 3 , left ACP was 0.71 ± 0.15 cm 3 , left and WOF was 3.20 ± 0.76 cm 3 . Removal of the right ACP expanded the right WOF by 22.21 ± 3.88%, and left ACP by 22.78 ± 5.50%. There was an approximately 25% increase in the WOF from the cadaveric dissections. Taking into account the variability of the ACP and OS, we proposed our own surgical classification of complicated (i acp ≥ 0.67; medium OS 2.5 mm ≤ 4.0 mm; wide OS ≥ 4.0 mm; ACP with pneumatization) and uncomplicated ACP (i acp 0.45 ≤ 0.67 mm; i acp ≤ 0.45; narrow OS ≤ 2.5 mm; ACP without pneumatization). Using this classification, we developed an algorithm for ACP dissection and removal. This was piloted in a clinical case of microsurgical clipping of a left internal carotid artery-posterior communicating artery aneurysm via the left minipterional approach. Conclusion  Extradural removal of ACP expands the WOF by approximately 25%, it helps neurosurgeons to improve proximal vascular control and avoid complications, and expands the range of indications for neurosurgical interventions in the skull base area.

Clinical and anatomical analysis of the epileptogenic spread patterns in focal cortical dysplasia patients

Background

Focal cortical dysplasia (FCD) is one of the main causes of intractable epilepsy, which is amendable by surgery. During the surgical management of FCD, the understanding of its epileptogenic foci, interconnections, and spreading pathways is crucial for attaining a good postoperative seizure free outcome.

Methods

We retrospectively evaluated 54 FCD patients operated in Federal Center of Neurosurgery, Tyumen, Russia. The electroencephalogram findings were correlated to the involved brain anatomical areas. Subsequently, we analyzed the main white matter tracts implicated during the epileptogenic spreading in some representative cases. We prepared 10 human hemispheres using Klinger's method and dissected them through the fiber dissection technique.

Results

The clinical results were displayed and the main white matter tracts implicated in the seizure spread were described in 10 patients. Respective FCD foci, interconnections, and ectopic epileptogenic areas in each patient were discussed.

Conclusion

A strong understanding of the main implicated tracts in epileptogenic spread in FCD patient remains cardinal for neurosurgeons dealing with epilepsy. To achieve meaningful seizure freedom, despite the focal lesion resection, the interconnections and tracts should be understood and somehow disconnected to stop the spreading.

Purely endoscopic biportal and monoportal removal of the choroid plexus papilloma of the third ventricle with bilateral spread to the lateral ventricles

Modern neuroendoscopy makes it possible to treat tumors of various localizations with a reduced risk of intra- and postoperative complications. In this video, the authors present biportal and monoportal techniques for the removal of the choroid plexus papilloma of the third ventricle with bilateral spread to the lateral ventricles in a 1-year-old boy. For this operation, they successfully used a new instrument for neuroendoscopy, LigaSure, specially designed for intra-abdominal surgery. The video can be found here: https://stream.cadmore.media/r10.3171/2023.1.FOCVID22170.

Usefulness of Intraoperative ultrasound for cortical dysplasia type I treatment - A single-center experience

Background

Focal cortical dysplasias (FCD) cause a subgroup of malformations of cortical development that has been closely linked to cause drug intractable epilepsy. Attaining adequate and safe resection of the dysplastic lesion has proved to be a viable option to archive meaningful seizure control. Of the three types of FCD (types I, II, and III), type I has the least detectable architectural and radiological abnormalities. This makes it challenging (preoperatively and intraoperatively) to achieve adequate resection. Intraoperatively, ultrasound navigation has proven an effective tool during the resection of these lesions. We evaluate our institutional experience in surgical management of FCD type I using intraoperative ultrasound (IoUS).

Methods

Our work is a retrospective and descriptive study, where we analyzed patients diagnosed with refractory epilepsy who underwent IoUS-guided epileptogenic tissue resection. The surgical cases analyzed were from January 2015 to June 2020 at the Federal Center of Neurosurgery, Tyumen, only patients with histological confirmation of postoperative CDF type I were included in the study.

Results

Of the 11 patients with histologically diagnosed FCD type I, 81.8% of the patients postoperatively had a significant reduction in seizure frequency (Engel outcome I-II).

Conclusion

IoUS is a critical tool for detecting and delineating FCD type I lesions, which is necessary for effective post-epilepsy surgery results.

Endoscopic Treatment of Middle Cranial Fossa Arachnoid Cysts in Children: Surgical Results of 65 Cases

OBJECTIVE

Congenital arachnoid cysts in the middle fossa accounts for 50% of all intracranial arachnoid cysts. Several management options have been described; however, no single technique has been universally adopted. We describe a series of pediatric patients with middle cranial fossa arachnoid cyst that were treated through an innovative minimally invasive endoscopic technique, along with their clinical aspects and surgical outcomes.

METHODS

Data from 65 patients operated between 2012 and 2018 were retrospectively analyzed. Follow-up ranged from 12 to 96 months. Clinical presentation and surgical outcomes were collected. Endoscopic cystocisternostomy was performed in all patients using a mini endoscope.

RESULTS

There were 41 male and 24 female patients, with a mean age of 5.3 years at the time of treatment. Except for 4 patients, all presented with 1 or more symptoms, and the most frequent were intracranial hypertension signs. All patients were treated with the same surgical technique, with an efficacy of 81.5%.

CONCLUSIONS

Using a mini endoscope allow us to perform multiple fenestrations along the arachnoid and deeply inspect the basal cisterns, achieving a much wider communication between the cyst and subarachnoid space with a high success rate and minimal invasiveness.

Endoscopic Interhemispheric Disconnection for Intractable Multifocal Epilepsy: Surgical Technique and Functional Neuroanatomy

BACKGROUND

Callosotomy represents a palliative procedure for intractable multifocal epilepsy. The extent of callosotomy and the benefits of adding anterior and posterior commissurotomy are debated.

OBJECTIVE

To describe a new technique of a purely endoscopic procedure to disconnect the corpus callosum, the anterior, posterior, and habenular commissures through the use of a single burr hole via a transfrontal transventricular route.

METHODS

Our surgical series was retrospectively reviewed in terms of seizure control (Engel's class) and complication rate. Five cadaveric specimens were used to demonstrate the surgical anatomy of commissural fibers and third ventricle.

RESULTS

The procedure may be divided into 3 steps: (1) endoscopic transventricular transforaminal anterior commissure disconnection; (2) disconnection of posterior and habenular commissures; and (3) total callosotomy. Fifty-seven patients were included in the analysis. A favorable outcome in terms of epilepsy control (Engel class 1 to 3) was found in 71.4% of patients undergoing callosotomy coupled with anterior, posterior, and habenular commissure disconnection against 53% of patients with isolated callosotomy (P = .26). Patients with drop attacks had better epilepsy outcome independently from the surgical procedure used.

CONCLUSION

The full endoscopic callosotomy coupled with disconnection of anterior, posterior and habenular commissures is a safe alternative to treat multifocal refractory epilepsy. A gain in seizure outcome might be present in this cohort of patients treated with total interhemispheric disconnection when compared with isolated callosotomy. Larger studies are required to confirm these findings.

Endogenous and Exogenous Factors Affecting the Surgical Technique (Review)

In this review, we analyzed essential factors affecting precise manual movements in microsurgery described in the medical literature. The search for publications in English and Russian languages was conducted in the PubMed database without limitation by the date of publication. The search was carried out according to the following descriptors: surgical procedures, dexterity, microsurgery, caffeine, alcohol, nicotine, physical exercise, sleep deprivation, posture. Only randomized and cohort studies involving doctors and students with surgical specialties were included in the analysis. We did not include papers in which only psychological (non-motor) aspects were studied.

Due to the limited number of publications meeting the inclusion criteria and conflicting results in some of them, the presented review does not allow us to formulate unambiguous conclusions and recommendations. Further studies (deep and fundamental) of endogenous and exogenous factors affecting the microsurgical technique are needed.

[Long association tracts of the human white matter: an analysis of 18 hemisphere dissections and in vivo HARDI-CSD tractography]

BACKGROUND

Anatomy of the conduction tracts of the cerebral cortex has been studied for a long time. Invention of diffusion tensor tractography renewed interest in this subject. The objectives of this work were to develop and improve protocols for dissection of the long association tracts of the human brain with studying the features of their segmentation, topography, and variability, compare the obtained data with the MR tractography data, and prepare for further clinical and anatomical studies.

MATERIAL AND METHODS

We used 18 cerebral hemispheres (from 10 males and 8 females; 9 left and 9 right hemispheres). The mean age of cadavers was 68 years. Specimen were fixated in accordance with the Klingler technique. Immediately after collection, specimens were placed in a 10% formalin solution for at least 4 weeks. After that, the pia was removed; specimens were frozen at -20 °C for a week and then unfrozen in a 96% ethanol solution for a day. We performed 10 lateral dissections, 2 lateral dissections with isolation of the frontal aslant tract, 2 basal dissections, 1 combined basolateral dissection, 2 frontal dissections, and 1 medial dissection. At the time of dissection and after it, specimens were stored in a 96% ethanol solution. Modified, disposable, therapeutic wooden spatulas were used for manipulations. A microscope (magnification of 6-40x) was used in 2 lateral and 2 basal dissections. MR tractography (HARDI-CSD) was carried out in 5 healthy volunteers using a GE Signa HDxt MRI scanner a field strength of 3.0 T.

RESULTS

We clearly identified the following fascicles: the arcuate fascicle (AF) and superior longitudinal fascicle (SLF) in 6/6 hemispheres on the right and in 5/6 hemispheres on the left, the inferior longitudinal fascicle (ILF) in 3/6 hemispheres on the left and in 4/6 hemispheres on the right, the uncinate fascicle (UF) in 4/4 hemispheres on the left and in 4/4 hemispheres on the right, and the inferior fronto-occipital fascicle (IFOF) in 4/4 hemispheres on the left and in 3/4 hemispheres on the right. Identification was less successful in the case of the frontal aslant tract (FAT) in 1/2 hemispheres on the left and in 0/2 hemispheres on the right. The used technique failed to identify the vertical occipital fascicle (VOF) of Wernicke, a segment of the superior longitudinal fascicle SLF I, and the middle longitudinal fascicle (MdLF). The MR tractography HARDI-CSD data were compared with the dissection data. We described in detail segmentation of the superior longitudinal, arcuate, and inferior fronto-occipital fascicles. Contradictory data were obtained for the superior longitudinal fascicle: a two-segment structure (SLFh and SLFv) was found in most (10/12) specimens, while a three-segment structure was revealed in the other (2/12) specimens (identified SLF II and SLF III). In the arcuate fascicle, the ventral and dorsal segments were successfully identified in 2/12 cases (1 left and 1 right), whereas identification failed in the other cases. During dissection of the inferior fronto-occipital fascicle, we could identify its surface layer in 1 of 8 cases (left) and its deep layer in one more case (left).

CONCLUSION

Examination of the long association tracts using the Klingler technique has significant limitations in the fiber intersection areas (sagittal striatum). The frontal aslant tract was least studied; we proposed a special anterior dissection technique for its isolation. The superior longitudinal fascicle can have both the two-segment (10/12) and three-segment (2/12) structure. Investigation of the segmental anatomy of the long association tracts will be continued in further dissections. When planning neurosurgical interventions in the projection areas of the long association tracts, both preoperative HARDI-tractography and anatomical dissections ex vivo, based on the proposed protocols, can be recommended for the operating surgeon to master a three-dimensional picture of the tract topography.

[The clinical picture of nonsyndromic craniosynostosis in children]

OBJECTIVE

to study clinical presentations of nonsyndromic craniosynostosis (NCS) in children.

MATERIAL AND METHODS

Authors analyzed 56 cases of different forms of NCS. To verify the diagnosis, all children underwent computed tomography with 3D cranial reconstruction.

RESULTS AND CONCLUSION

The distribution of diagnoses was as follows: scaphocephaly - 28 (50%) patients, trigonocephaly - 21 (38%), different forms of plagiocephaly - 7 (12%). On admission to the hospital, 25 (43%) patients were diagnosed with perinatal CNS damage, 10 (18%) were born premature, 33 (59%) had neurological deviations. The clinical picture of NCS was polymorphic that might explain an increase in the number of children with late-diagnosed craniosynostosis. The early diagnosis of NCS which is the basis for using less invasive surgical methods is particularly important for prognosis.

Endoscopic monoportal removal of a choroid plexus papilloma in the posterior third ventricle in a child

Currently, only a few reports describe the minimally invasive removal of choroid plexus papillomas (CPPs) and, to the best of the authors' knowledge, no reports detail the resection of such a papilloma through an endoscopic approach in infants. The authors here describe the endoscopic removal of a third ventricle CPP in a child. A 5-month-old male infant presented with progressive macrocephaly, vomiting, and convulsions. A lesion in the posterior third ventricle was detected on brain MRI. Because of the patient's very young age, neuroendoscopy was used as the least invasive technique. The tumor was completely resected through a monoportal neuroendoscopic approach. Histologically, the tumor was classified as a WHO Grade I CPP. After surgery, the patient's condition improved, with no complications during his recovery. Ten-month follow-up neuroimaging revealed no evidence of tumor recurrence or progressive hydrocephaly. In view of the successful neuroendoscopic excision of this posterior third ventricle CPP, the authors believe that this method seems promising in the treatment of young children with intraventricular lesions.

Biportal endoscopic removal of choroid papilloma of the lateral ventricle in a child

The article is devoted to the use of minimally invasive techniques for removing intraventricular tumors; this topic is currently relevant to pediatric neurosurgery. As an example, a clinical case of complete removal of a choroid plexus papilloma in a child using the neuroendoscopic technique through the biportal approach is provided. This tumor is most commonly found in pediatric practice. Taking this into account, the use of minimally invasive surgical methods for treating this pathology is very important. The published data relating to this pathology, as well as to the use of neuroendoscopy for this disease, are fragmentary today. Therefore, one of the objectives of this work was to analyze the literature regarding etiopathogenesis, clinical presentation, diagnostic features, and some aspects of surgical treatment of choroid plexus papilloma, in connection with which this work is primarily of practical interest.

Surgical aspects of endoscopic treatment of sagittal craniosynostosis (scaphocephaly) in children

The article is devoted to the surgical treatment of sagittal craniosynostosis in children. Among non-syndromic monosynostosis sagittal craniosynostosis (scaphocephaly) is the most common. Treatment of children with craniosynostosis should begin as soon as possible. Endoscopic method refers to minimally invasive technique in surgical correction of craniosynostosis. This article presents a features of surgical treatment at all stages of the endoscopic cranioplasty. Presented data is based on the experience of treatment of 20 children with primary sagittal craniosynostosis. Treatment was performed using endoscopic techniques, special tools designed specifically for the endoscopic cranioplasty.