Shunt System Research Articles

BIOM-50. SERIAL INTRACRANIAL CEREBROSPINAL CELL-FREE DNA FOR DISEASE MONITORING IN PATIENTS WITH GLIOMAS

Abstract Improved response assessment methods are needed for patients with gliomas. Intracranial cerebrospinal fluid (CSF) is longitudinally accessible and provides an abundance source of candidate biomarkers, such as cell-free DNA (cfDNA), for disease monitoring. To evaluate the clinical feasibility of molecular profiling from longitudinal intracranial CSF, CSF was acquired from patients with CSF access devices, including Ommaya reservoirs and ventriculoperitoneal shunts. cfDNA was extracted and analyzed via PredicineCARE (Next Generation sequencing) or PredicineSCORE (low pass whole genome sequencing). Five patients (2 females, 3 males; median age: 40 years, range 32-64 years) underwent longitudinal intracranial CSF collection via Ommaya reservoirs (n=4) or VP shunt (n=1). In total, forty-eight CSF samples were obtained (median volume: 4.00 mL; 0.5-5 mL), with 39 samples (81.3%) yielding sufficient cfDNA for variant profiling. Our initial findings suggest that tumor fraction increased by 6.28x, 2.87x, and 8.31x with radiographic progression in three patients. Tumor fraction decreased by 0.08x and 0.04x in two patients with paired immediate pre-versus-post chemoradiation samples. Despite ongoing pseudoprogression in one patient, tumor fraction decreased to unmeasurable levels from a post-resection baseline of 0.26. Patient-specific tumor-associated variant allelic frequencies (VAFs), including TP53, PTEN, TERT, and CDKN2A/B, decreased within individual patients after resection and chemoradiation. In two patients with isocitrate dehydrogenase (IDH) mutant gliomas, decreasing IDH1 VAF after resection and chemoradiation correlated with decreased CSF D-2-hydroxyglutarate (D-2-HG) levels (0.64x and 0.62x, respectively, for the first patient, and 0.01x and 0.07x for the other patient). Both CSF IDH1 VAF and CSF D-2-HG increased a patient who had radiographic progression (2.56x and 9.21x, respectively). Moreover, CNB decreased below the limit of quantification during treatment and increased above the limit at progression. In conclusion, longitudinal CSF cfDNA can feasibly be obtained via CSF access devices in patients with gliomas during their disease course toward evaluating candidate monitoring biomarkers.

RADT-07. HYPOFRACTIONATED RADIOTHERAPY IN BRAINSTEM GLIOMAS- EXPERIENCE FROM A TERTIARY CARE CENTRE IN INDIA

Abstract Brainstem Gliomas have limited therapeutic options and poor outcomes. Radiation forms the cornerstone of management but data is lacking. We performed an audit of brainstem glioma patients treated with hypofractionated radiation between July 2021 to May 2024. Diagnostic MRI was co-registered with planning CT to delineate GTV with an isotropic 5 mm margin for CTV and 3mm for PTV. Baseline clinical and imaging details, radiation details, acute toxicities, steroid usage, progression, and overall survival data were recorded. PFS and OS were defined from the date of diagnosis to progression and death respectively. This study included 31 Brainstem glioma patients. The median age at presentation was 14 years (2–80 years). Majority of patients were male (67.7%). The baseline performance status assessed by ECOG/Lansky was 0-2 in 83.9%. The most common presenting complaint was motor weakness in 51.6% followed by cerebellar symptoms in 29%. Baseline neurological deficit was seen in 90.3%. The most common epicenter of the disease was pons (67.7%). Biopsy was available in only 9.7% (2 patients: Diffuse Midline Glioma H3k27 altered,1: High-Grade Glioma). VP shunting was done in 29%. All patients were planned via VMAT technique. Median GTV volume 34.3cc (4.9-109.5cc). Median PTV volume was 95.1 cc (7.9-363.1 cc). Most frequently used regimen was 40Gy/15#/3 weeks in 74.3% of patients. Median PTV coverage D95% was 98.7% (90.5-99%). Only one patient received concurrent Temozolamide. Median Radiation treatment time was 22.5 days (-46 days). Steroid usage during radiation was seen in 41.9% of the patients. Naso-gastric tube was required in 12.9% patients. During radiation, aspiration and raised ICT were seen in in 12.9% each. At a median follow-up of 6.42 months, the median PFS was 6.42 months (3-9.83 months) and OS was 7.18 months (3-11.37 months). Hypofractionation seems a feasible approach in brainstem gliomas. International collaborative efforts are required.

Hair-sparing approach versus traditional hair clipping for cerebral spinal fluid shunt procedures: a retrospective comparative study.

Cerebral spinal fluid (CSF) diversion methods, including ventriculoperitoneal (VP) shunts, are the standard treatment for hydrocephalus. Hair clipping (HC) has been a routine neurosurgical practice of the great majority of neurosurgeons, due to the perception that this will either decrease the risk of shunt infection or allow for a faster, unimpeded opening and closing of the skin. The benefits of not cutting or clipping hair in terms of normalizing appearance and self-esteem are obvious. The purpose of this study was to assess whether the rate of shunt infection would differ between pediatric patients receiving operation via the hair-sparing (HS) approach versus HC. A retrospective single-institution study comparing HS versus HC was conducted on pediatric patients undergoing long-term CSF shunt procedures at the Montreal Children's Hospital between August 2014 and April 2021. The primary outcome measure was shunt infection at 90 days and at long-term follow-up. Inclusion criteria were having at least 18 months of follow-up after long-term CSF shunt procedures, including insertions or revisions of VP shunts, ventriculoatrial shunts, cystoperitoneal shunts, subdural-peritoneal shunts, ventriculosubgaleal shunts, and ventriculosubgaleal reservoirs. Excluded procedures were those involving external ventricular drains, externalized shunts, Omaya reservoirs, endoscopic third ventriculostomies, and lumbar shunts. There were 434 CSF shunt procedures performed in 226 unique patients; 155 (35.71%) procedures were done using the HS approach versus 279 (64.29%) procedures via HC. At 90 days postoperatively, the infection rate was 1.29% in the HS group and 2.87% in the HC group, with an absolute risk difference of 1.58% (95% CI -1.07% to 4.23%, p = 0.24). At long-term follow-up (mean follow-up: 752 days and 716 days for the HS and HC groups, respectively), the rate of shunt infection remained at 1.29% for the HS group (no new infections) but rose to 4.66% for the HC group, with an absolute risk difference of 3.37% (95% CI 0.33%-6.41%, p = 0.03). Performing CSF shunt procedures without cutting or clipping any hair has a very low risk of shunt infection, and certainly does not appear to increase the risk of infection (or malfunction) versus the hair removal approach. It is a safe alternative and should be considered due to its esthetic and psychological benefits regarding normalization of appearance and ease of resuming a normal life following shunt surgery.

Current Trends in the Treatment of Pediatric Hydrocephalus: A Narrative Review Centered on the Indications, Safety, Efficacy, and Long-Term Outcomes of Available Treatment Modalities

The pathophysiologic substrate of pediatric hydrocephalus has not been thoroughly elucidated. Valve-based shunt systems have constituted the main therapeutic option since the late 1950s. The initially used systems were concerning the ventricular system and the atrium. In the 1970s, VA shunts were not the main stay of treatment as the preferred option for the terminal end of the drainage system was the peritoneum. Our review analyzes these valve types and attempts a comparison, based on their functional characteristics. Nowadays, the only available surgical alternative for the treatment of hydrocephalus is ETV. This technique is associated with lower infection rates as well as, on average, a lower re-operation rate. Another term that deserves special mention is related to the outcome of ETV in children who had a medical history of previously incorporated shunts and who were subsequently suffering from shunt malfunction. Well-recognized predictive factors associated with secondary ETV failure include age, early onset of hydrocephalus, and prematurity. Although several attempts have been made in order to establish the optimum surgical treatment management in the different subgroups of patientswho are suffering from shunt dysfunction, there is no universal agreement. Therefore, this review attempts to identify the specific subpopulations of patients in whom the insertion of a drainage system as the preferred treatment modality is associated with an optimum long-term prognosis, compared to ETV, and vice versa. The objective of our study is to analyze the safety, efficacy, and outcomes of drainage devices and ETV in pediatric hydrocephalus patients.

The Ventriculoperitoneal Shunt Complication Rate in Baghdad Medical City from 2019 to 2022

Background and aimsDue to the substantial lack of data from Iraq on ventriculoperitoneal shunt (VPS) complications, this study aims to examine the various types of complications after VPS surgery in Baghdad Medical City. MethodsThe retrospective cohort study analyzed VP shunt procedures at Baghdad Medical City from 2019 to 2022. The overall complication rate, including infection and shunt malfunction, was determined from patient records. Data were analyzed using descriptive statistics and Kaplan-Meier survival analysis. Ethical approval was obtained from the IRB, with consent waived due to the study's retrospective nature. The findings highlight the need for improved management to reduce complication rates in VP shunt procedures. ResultsThe study involved 113 participants with an average age of 2.62 years (±3.4). The most common indications for VPS placement are congenital hydrocephalus (40%) and post-infectious hydrocephalus (30%). The most common complications of post-VPS surgery are VP obstruction (54%) and post-surgical infections (44%). There were no significant differences in the incidence of post-operative complications across different age groups. ConclusionOur study showed the significant complication rate associated with VPS surgeries for hydrocephalus, particularly VPS infections and obstruction. There were no significant age-related differences in VPS complication rates across age groups.

Variability in treatment of postoperative pain in children with severe neurologic impairment.

Treatment of postoperative pain for children with severe neurologic impairment (SNI) is challenging. We describe the type, number of classes, and duration of postoperative pain medications for procedures common among children with SNI, as well as the variability across children's hospitals in pain management with an emphasis on opioid prescribing. This retrospective cohort study included children with SNI ages 0-21 years old who underwent common procedures between January 1, 2019 and December 31, 2019 within 49 children's hospitals in the Pediatric Health Information System. We defined SNI using previously described high-intensity neurologic impairment diagnosis codes and identified six common procedures which included fracture treatment, tracheostomy, spinal fusion, ventriculoperitoneal shunt placement (VP shunt), colostomy, or heart valve repair. Medication classes included benzodiazepines, opioids, and other nonopioid pain medications. Acetaminophen and nonsteroidal anti-inflammatory drugs were excluded from analysis. All findings were summarized using bivariate statistics. A total of 7184 children with SNI underwent a procedure of interest. The median number of classes of pain medications administered varied by procedure (e.g., VP shunt: 0 (interquartile range [IQR] 0-1); tracheostomy: 3 (IQR 2-4)). Across all procedures, opioids and benzodiazepines were the most commonly prescribed pain medications (48.8% and 38.7%, respectively). We observed significant variability in the percentage of postoperative days with opioids across hospitals by procedure (all p < .001). There is substantial variability in the postoperative delivery of pain medications for children with SNI. A standardized approach may decrease the variability in postoperative pain control and enhance care for children with SNI.

Minimally invasive management of a spinal arachnoid cyst with ultrasound-assisted catheter placement: illustrative case.

Spinal arachnoid cysts are cerebrospinal fluid-filled sacs that are frequently located within the thoracic spine and can lead to symptoms due to direct compression of the thoracic spinal cord. These lesions are typically treated with laminectomy and fenestration of the cyst, with or without shunting. However, with recurrence, treatment is often more complex and sometimes requires re-exposure and fenestration or shunting. Here, the authors describe a 57-year-old female with a thoracic intradural arachnoid cyst that recurred despite extensive and initially successful fenestration. Given the failure of fenestration, the authors instead attempted to place a cystoperitoneal shunt. Given how extensive her laminectomy was, the authors elected to perform the procedure under ultrasonic guidance to avoid the large incision required for open shunt placement. The procedure was successful, with gradual improvement in the size of the arachnoid cyst as well as symptomatic improvement. Here, the authors present a unique minimally invasive technique to treat recurrent spinal arachnoid cysts. They successfully demonstrated the feasibility and safety of this approach in shunting the cyst while avoiding the extensive re-exposure often required in such complex cases. https://thejns.org/doi/10.3171/CASE24461.

The trends in diagnosis, management, and care of patients with diffuse intrinsic pontine gliomas: Perspectives from a tertiary care hospital of pakistan.

Diffuse intrinsic pontine glioma (DIPG) primarily affects pediatric patients. Data on the global incidence of DIPG remain sparse, especially in South Asia and low-middle-income countries like Pakistan. After exemption from the Ethics Review Committee, a retrospective study was conducted. Records of patients with DIPG at the Aga Khan Hospital in Karachi, from January 2010 to December 2022, were reviewed. A total of 35 pediatric patients were managed for DIPG. The median age of the patients was 9, with 19 (54.3%) males and 16 (45.7%) females. Cranial nerve palsies were the most common complaint and were present in 19 (54.3%) patients, followed by headaches in 18 (51.4%), long tract signs in 14 (40%), ataxia/cerebellar symptoms in 14 (40%), and seizures in 5 (14.3%). MRI was the primary diagnostic tool, used alone or with CT in 32 (94.1%) patients; CT alone was used in only 2 (5.7%) patients. Biopsy was performed in 10 (28.6%) patients. Primary radiation therapy was administered to 14 (40%) patients with 5400 cGy in 30 fractions. All these patients received steroids while none of them received reirradiation. VP shunt surgery for hydrocephalus was performed in 9 (25.7%) patients. Over half (54.3%) refused treatment post-diagnosis, and 71.4% were lost to follow-up. Providing timely, quality multi-disciplinary care to DIPG patients within resource constraints remains challenging in Pakistan. However, recent developments show promise for improving DIPG care in the country.

Comment on, "Superb microvascular ultrasound is a promising non-invasive diagnostic tool to assess a ventriculoperitoneal shunt system function: a feasibility study".

This study by Brawanski et al. (2024) contributes significantly to neurosurgery by assessing ventriculoperitoneal shunt (VPS) function using superb microvascular ultrasound (SMI). The authors provide a thorough evaluation of SMI as a novel, non-invasive diagnostic tool, demonstrating its effectiveness in detecting cerebrospinal fluid (CSF) flow within VPS systems. By focusing on asymptomatic hydrocephalus patients, the study offers a less invasive alternative to traditional diagnostic methods, potentially reducing the need for exploratory surgeries. However, the study could have been strengthened by exploring the variability of SMI measurements under different physiological conditions and including symptomatic patients. Additionally, further analysis of the long-term reliability of SMI is needed. Future research should expand the study's scope to assess SMI's diagnostic capabilities across varied conditions and explore its integration with other non-invasive techniques, thereby enhancing its clinical utility in managing hydrocephalus and VPS functionality.

Power Quality Enhancement in High-Voltage Transmission Systems Using STATCOM by Type 1 and Type 2 Fuzzy Logic Controllers

The continuing growth of load demand leads to increased power system complexity and interconnections. During faults and abnormal operating conditions, conventional power systems change the load flow in transmission lines, which may cause voltage drops or swells, and other power quality issues. Voltage regulation is connected to reactive power compensation in system busbars, and fixed capacitor banks are usually used for this purpose, but they are not flexible and dynamic enough to meet the power quality requirements. With power electronics development, flexible alternative current transmission systems (FACTS) became a popular solution for power quality improvement and power transmission capability increment in power systems, and FACTS can be categorized into series and shunt systems. In this study, STATCOM was used to improve the voltage profile in part of Iraq’s high-voltage transmission system during abnormal operating conditions, such as sudden load addition and removal, which causes voltage dip and voltage swell. Type 1 fuzzy logic controller and type 2 fuzzy logic controller were used as the outer controller in the STATCOM; both controllers were able to regulate the voltage magnitude by reducing the voltage dip from 1.32 to 0.4%, voltage swell from 1.02 to 0.5%, and voltage THD at the connecting point did not exceed 3%, indicating that SATACOM with FLC improves the voltage profile under different operating conditions.

Seizure Risk Associated With the Use of Transcranial Magnetic Stimulation for Coma Recovery in Individuals With Disordered Consciousness After Severe Traumatic Brain Injury.

Repetitive Transcranial Magnetic Stimulation (rTMS) is emerging as a promising treatment for persons with disorder of consciousness (DoC) following traumatic brain injury (TBI). Clinically, however, there are concerns about rTMS exacerbating baseline seizure risk. To advance understanding of risks, this article reports evidence of DoC-TBI rTMS-related seizure risk. Acute and sub-acute hospitals. Persons in states of DoC 6.5months to 15years after TBI (n=20) who received active rTMS (n=17) or placebo rTMS (n=3). After completing placebo procedures, placebo participants completed active rTMS procedures. These 3 participants are included in the active group. Meta-analysis of data from 3 clinical trials; 2 within-subject, 1 double blind randomized placebo-controlled. Each trial used the same rTMS protocol, provided at least 30 rTMS sessions, and delivered rTMS to the dorsolateral prefrontal cortex. During each study's rTMS treatment phase, seizure occurrences were compared between active and placebo groups using logistic regression. After stratifying active group by presence/absence of seizure occurrences, sub-groups were compared using contingency chi-square tests of independence and relative risk (RR) ratios. Two unique participants experienced seizures (1 active, 1 placebo). Post seizure, both participants returned to baseline neurobehavioral function. Both participants received antiepileptics during remaining rTMS sessions, which were completed without further seizures. rTMS-related seizure incidence rate is 59 per 1000 persons. Logistic regression revealed no difference in seizure occurrence by treatment condition (active vs placebo) or when examined with seizure risk factors (P >.1). Presence of ventriculoperitoneal shunt elevated seizure risk (RR=2.0). Collectively, findings indicate a low-likelihood that the specified rTMS protocol exacerbates baseline seizure rates in persons with DoC after TBI. In presence of VP shunts, however, rTMS likely elevates baseline seizure risk and mitigation of this increased risk with pharmacological seizure prophylaxis should be considered.

Dynamic plain abdominal film provides simple and effective diagnosis of delayed shunt insufficiency caused by abdominal adhesions after VP shunt

BackgroundMany complications may occur after placement of the ventriculoperitoneal shunt (VP shunt) for hydrocephalus, and delayed shunt insufficiency (DSI) is among the most common. It is often caused by abdominal adhesions, which increases the difficulty of diagnosis. This study aimed to explore the clinical value of dynamic plain abdominal radiography (DPAR) as a simple diagnostic method for patients with DSI due to terminal adhesion of the peritoneal shunt after VP surgery.MethodsA total of 30 patients with high suspicion of DSI due to abdominal adhesions after VP surgery were included. DPAR was used for prospective assessment. The interval between the first and second PAR was 4–6 h before surgery. If two plain abdominal radiography at different times indicated that the end of the shunt tube in the abdominal segment was fixed, it was diagnosed as DSI due to adhesion of the shunt tube at the abdominal end. The peritoneal end of the shunt tube was surgically repositioned. Postoperative DPAR was repeated to evaluate the distance of the shunt outlet within the abdominal segment.ResultsAll cases showed clinical symptoms or imaging findings of shunt insufficiency. The diagnostic accuracy of DPAR was 96.67% (29/30). The end of the shunt tube in the abdominal segment of the preoperative group was fixed with abdominal plain film twice with a mean difference of 1.74 ± 1.18 cm. The mean postoperative change in the position of the end of the shunt tube in the abdominal section was 9.36 ± 2.64 cm, showing a significant difference compared with the preoperative group (P < 0.001). The mean postoperative EVANs index (0.37 ± 0.08) was significantly lower than the preoperative (0.42 ± 0.08) (P = 0.007), Glasgow coma scale score (12.8 ± 2.69) was higher than the mean preoperative score (11.36 ± 2.43) (P = 0.013).ConclusionDPAR is a simple and effective method for the diagnosis of shunt insufficiency caused by delayed abdominal end adhesion after VP shunt.

Superb microvascular ultrasound is a promising non-invasive diagnostic tool to assess a ventriculoperitoneal shunt system function: a feasibility study

The objective of this pilot study was to assess the reliability of superb microvascular ultrasound (SMI) for the measurement of the cerebrospinal fluid (CSF) flow within VPS systems as an indirect sign for shunt dysfunction. Asymptomatic hydrocephalus patients, with a VPS system implanted between 2017 and 2021, were prospectively enrolled in the study. Using SMI, the CSF flow within the proximal and distal catheters were analysed. Before and after pumping the shunt reservoir, intraabdominal free fluid, optical nerve sheath diameter (ONSD), and papilla diameter (PD) were evaluated and correlated with the amount of valve activation. Nineteen patients were included. A flow was detectable in 100% (N = 19) patients in the proximal and in 89.5% (N = 17) in the distal catheter. The distal catheter tip was detectable in 27.7% (N = 5) patients. Free intraabdominal fluid was initially detected in 21.4% (N = 4) patients and in 57.9% (N = 11) at the end of the examination (P = 0.049). ONSD was significantly lower after pump activation (4.4 ± 0.9 mm versus 4.1 ± 0.8 mm, P = 0.049). Both peak velocity and flow volume per second were higher in proximal compared to distal catheters (32.2 ± 45.2 versus 5.6 ± 3.7 cm/sec, P = 0.015; 16.6 ± 9.5 ml/sec versus 5.1 ± 4.0 ml/sec, P = 0.001, respectively). No correlation was found between the number of pump activations and the changes in ONSD (P = 0.975) or PD (P = 0.820). SMI appears to be a very promising non-invasive diagnostic tool to assess CSF flow within the VPS systems and therefore affirm their function. Furthermore, appearance of free intraperitoneal fluid followed by repeated compression of a shunt reservoir indicates an intact functioning shunt system.

Complications of intrathecal baclofen therapy in children and young adults

OBJECTIVE The primary objective of this study was to determine the frequency and nature of complications that occur during intrathecal baclofen (ITB) therapy, including nonsurgical complications as well as complications associated with both implantation surgeries and subsequent revisions. METHODS The authors retrospectively reviewed the medical records of all patients who had baclofen pumps implanted at a tertiary children’s hospital from 2006 through June 2019. The study employed appropriate descriptive statistics and statistical models to analyze patient demographics, improvements in tone, and clinical complications. The authors evaluated the associations of complications as well as changes in modified Ashworth Scale (MAS) scores with various preexisting conditions (e.g., presence of gastrostomy tubes [G-tubes] and ventriculoperitoneal [VP] shunts) and surgical variations (e.g., use of newer [Ascenda] catheters and subfascial versus subcutaneous catheter tunneling). RESULTS One hundred forty-two pumps were implanted. Complications occurred in 111 patients (78.2%). The most frequent complications were catheter complications and pseudomeningoceles, each of which occurred in 63 (44%) patients. On multivariable analysis, pseudomeningoceles and percutaneous CSF leaks were significantly less likely when intrathecal catheters were placed via laminotomy versus spinal needle (OR 4.6, p = 0.044), and when catheters were passed from the posterior incision to the abdominal pump pocket deep to the thoracolumbar fascia rather than superficial to it (OR 2.7, p = 0.008). Preexisting G-tubes and VP shunts at the time of pump implantation were not associated with a significantly increased likelihood of pump malfunction or infection. Ascenda catheters were significantly less likely to have disconnections (p &lt; 0.001) and obstructions (p = 0.016), and overall were less likely to have any catheter-related complications (p = 0.01). Patients with preexisting VP shunts at the time of implantation had a significantly greater mean decrease in MAS scores in both their lower extremities (1.8, p = 0.003) and upper extremities (1.3, p = 0.002) than did patients without shunts. CONCLUSIONS Various complications are associated with ITB therapy, most commonly catheter complications and pseudomeningoceles. There have been fewer catheter complications associated with the newest catheter model, while pseudomeningoceles have become less frequent since the surgical technique was modified to prevent them. VP shunts and G-tubes are not associated with significantly higher complication rates and shunts seem to be associated with greater efficacy of ITB therapy, as represented by a greater mean improvement in MAS scores.

Unforeseen outcomes: Unveiling cyst formation post stereotactic radiosurgery in brain arteriovenous malformations cases

IntroductionCyst formation after stereotactic radiosurgery (SRS) for brain arteriovenous malformations (AVMs) is a rare, delayed but important complication. Prompt recognition and appropriate treatment is essential for good outcome. MethodsWe analysed our institute’s Gamma knife treatment records from 2008 to 2023 and analysed AVM treated patients by gamma knife radiosurgery (GKRS). Patients with cyst formation and with adequate follow up were identified. Clinical details, management and prognosis of these patients was studied in detail along with prior literature review. ResultsA total of 921 AVM patients were treated in the above period and 7 patients were identified with cyst formation. The mean nidus volume was 12.98 ml, the mean radio surgical marginal dose was 23.57 Gy and maximal dose 47.21 Gy. The mean interval gap between SRS and cyst detection was 6.45 years. The mean volume of cyst cavity formed was 47.85 ml. Patients presented either with features of raised intracranial pressure (3) or focal neurological deficits (3) or seizures (1). 3 patients had achieved angiographic nidus obliteration at the time of cyst detection. Treatment was mostly on surgical lines with cyst fenestration(2 patients), excision (3 patients) and emergency decompressive craniectomy (1 patient). 1 patient required additional Ommaya insertion. Conservative management was followed for 1 patient. Residual nidus was treated either by concomitant excision or embolization or redo GKRS.Favourable outcome was seen in 6 out of 7 patients (85.71%) post cyst management with symptomatic and radiological improvement whereas 1 patient (14.28%) died due to refractory status epilepticus secondary to malignant cerebral edema. ConclusionCyst formation after GKRS for AVM treatment is an often-neglected complication due to its low incidence and often long latency period. Long term follow up of patients is hence necessary for prompt recognition. Diagnostic DSA should be done in all patients with cysts to look for residual nidus. Asymptomatic ones can be followed up conservatively while surgical treatment is required for symptomatic cases. Ventricular diversion like Ommaya or cystoperitoneal shunt may be necessary in some cases. Treatment outcome is usually favourable provided timely detection is done.

Middle fossa arachnoid cyst fenestration for ruptured cysts associated with subdural collections: paediatric neurosurgery tertiary unit experience.

Arachnoid cysts are commonly encountered benign cystic structures and often come to attention as incidental findings following cranial imaging. Surgical intervention rates vary in different studies; however, rupture of cyst and subdural collection with mass effect are some of the indications for surgical intervention. In this study, we aimed to evaluate our operated cohort of middle fossa arachnoid cysts to determine the rate of traumatic subdural collection in this cohort and further assess outcomes. A retrospective review of all consecutive operated middle cranial fossa arachnoid cysts was carried out for the period 2010 to 2024. Demographics including age, sex, Galassi type, surgical technique for fenestration, preceding history of trauma, presence of papilloedema, and complications following surgery were extracted. Indication for surgery included papilloedema and headaches or increasing head circumference or rupture and subdural collections. Arachnoid cysts managed with CSF diversion as primary surgery were excluded. Over the study period, 21 fenestrations of the arachnoid cysts were carried out in 19 patients with mean age of 7years and M:F ratio of 2.2:1 (laterality: 9 right-sided and 10 left-sided). These included seven Galassi 2 and twelve Galassi 3 arachnoid cysts. At presentation, 10 had papilloedema, 5 with no papilloedema, and 4 with no available ophthalmological assessment. Fenestration of cyst included 12 microscopic, 6 endoscopic, and 3 combined approaches. Of the operated cohort, 8 were due to rupture of arachnoid cyst and subdural collections causing mass effect. Of 8 cases of ruptured arachnoid cyst with subdural collections, 75% had clear history of preceding head injury in the context of accidental or sports-related injuries. Two patients required redo-fenestration (10.5%), 1 patient required temporary lumbar drain (5.2%), and 2 patients required cysto-peritoneal shunts (10.5%). Rupture of arachnoid cysts and subdural collections although rare can be associated with head injury in majority of cases. All operated cases belonged to grade 2 and 3 Galassi.

Atypical arachnoid cyst with progression: a case report

A 26-year-old female patient applied to the outpatient clinic in 2018 due to pain that had been present for a long time (16 years) and had recently spread from the top of the head to the nape of the neck. It was learned from the patient's anamnesis that her pain was relieved with analgesics. Although no pathological findings were found in the neurological examination, brain MRI was requested to reveal possible intracranial pathological conditions. In the MRI images taken, a cystic mass with a lobulated contour and thin septa of 24x31x40 mm and similar intensity to CSF was detected in the right parasagittal area posteriorly at the vertex level. The patient's control brain MRI images 3 months later showed no increase in cyst size. However, the patient's anamnesis, which came for a control in 2022, showed that his current complaints and headaches had increased. The MR images showed that the existing cyst had reached a size of approximately 60x35 mm. Medical treatment was initially planned for the patient (Acetazolamide, 750 mg/day). The MR taken one month later showed that there was no reduction in the cyst size and the optic discs were slightly swollen in the fundus examination. Considering the cyst growth, the patient's failure to benefit from medical treatment and the swelling noted in the optic discs, the patient was fitted with a cystoperitoneal shunt. The patient's early postoperative tomography image showed a significant reduction in the cyst (50.15x25.66) and a slightly swollen optic disc image with blurred borders was detected in the fundus examination. The patient's complaints regressed, and in the radiological images it was determined that the cyst continued to shrink [(45.8x23.19 mm) and (41.1x20.3 mm)], the shunt was in place, and she had no clinical complaints. As a result, it was argued that patients with atypically located arachnoid cysts, as in this case, should be taken under close clinical and radiological follow-up, and surgical treatment methods should definitely be considered in patients who are found to have an increase in cyst size and clinical findings during this follow-up and who do not respond despite medical treatment.

Design of solar and energy storage systems fed reduced switch multilevel converter with flower pollination optimization

In the present situation, the growing use of power electronic devices and non-linear loads has led to power quality (PQ) issues, including harmonics and poor power factor, which adversely affect the distribution network. This study contributes a design of shunt active power filter, powered by solar energy and energy storage systems, to address these PQ issues. To minimize losses, a five-level reduced-switch voltage source converter has been considered. Additionally, a neural network-based reference signal generation method is used, eliminating the need for conventional synchronous reference frame and active-reactive power theories, along with their complex abc and αβ0 transformations. This work also includes the optimal selection of the shunt filter and the gain parameters for the proportional-integral-derivative (PID) controller used in the shunt and battery control system. These parameters, along with the weights and biases of the neural network, are optimally determined using a nature-inspired flower pollination optimization algorithm.The proposed system has three primary objectives: (1) stabilizing the voltage across the DC bus capacitor, (2) reducing total harmonic distortion (THD) and improving the power factor (PF), and (3) ensuring the power management under the varying irradiation and load conditions. The effectiveness of the proposed system is evaluated through three testing scenarios, with results compared to conventional SRF and pq methods using a proportional-integral controller (PIC). The analysis reveals that the THD for the case studies is 3.32 %, 2.93 %, and 3.98 %, significantly lower than the other techniques compared. Additionally, the PF is nearly at unity, with a lower settling time of 0.05 s for the DC bus voltage.

Technical note: durable resolution of hydrocephalus after ultrasound-guided percutaneous fenestration of giant suprasellar arachnoid cyst in a neonate.

Arachnoid cysts are relatively common, but rarely require intervention. While most arachnoid cysts in typical middle or posterior cranial fossa locations are seldom symptomatic, suprasellar cysts may become symptomatic due to the potential for ventricular outflow obstruction and hydrocephalus. Typical standard of care for the treatment of these lesions is endoscopic fenestration with third ventriculostomy, or the placement of ventriculoperitoneal or cystoperitoneal shunts. The surgical and anaesthetic risks of traditional interventions may be higher in the early neonatal period, including leak of cerebrospinal fluid, infection, and premature failure of ventriculostomy or shunts. This note describes a novel bedside ultrasound-guided technique to percutaneously fenestrate large suprasellar arachnoid cysts under local anaesthesia. The technique involves insertion of a 25-g spinal needle until contact with the membrane of the arachnoid cyst medially, followed by a lateral sweeping to widely incise/fenestrate the lesion into the ventricular space under continuous ultrasound visualisation. This note describes an example case which demonstrates durable radiological and clinical improvement after 2years of follow-up. This may represent a management option to temporise, or perhaps definitively manage suprasellar arachnoid cysts in the neonatal period.

ICU Management of Post-Craniotomy Patients with Schwannoma Vestibular Tumor Removal

Background: Vestibular schwannoma (VS) is a relatively common tumor that arises from the vestibulocochlear nerve (CN VIII) and represents 80% of cerebellopontine angle (CPA) masses. CPA tumors are mostly benign, slow growing with low malignant potential (~1%). VS have rarely been reported, and there is a lack of in-depth discussion on the experience of management of massive acoustic neuromas in ICU. It represents the case in which the patient presented with obstructive hydrocephalus and progressive neurological deficits. The purpose of this case report is to understand the management of post-operative patients with VS with several comorbidities in the ICU.Case: We present a 53 years old woman with a giant VS and obstructive hydrocephalus. An imaging findings revealed a brain tumor in the CPA region and obstructive hydrocephalus. Consequently, she relieved her hydrocephalus with a ventriculoperitoneal shunt (VP shunt). After 1.5 years, her mental condition deteriorated, and her left limb muscle strength gradually decreased. Under a joint consultation with Department of Neurosurgery and Anesthesiology, she underwent tumor removal. Upon discharge, the previously observed neurological deficits, which were reversible had been successfully resolved. The neuroimaging confirmed the complete tumor removal, while the neuropathologic examination revealed a VS.Discussion: If untreated, an acoustic neuroma can grow large enough to cause pressure on the brain stem. The tumor can block the flow of cerebrospinal fluid (CSF) between the brain and the spinal cord, causing a buildup of the fluid in the brain. Because the skull is a closed structure, excess fluid in the brain (hydrocephalus) can press against the brain, causing unsteady movement and lack of coordination (ataxia), headaches and confusion. Patients with brainstem compression had significantly longer mean LOS than patients without. Also, the dissection of the facial nerve from the tumor in order to preserve it can sometimes cause swelling, which can result in weakness or paralysis (complete or partial loss of muscle function). This is usually temporary but can take weeks to months to recover. After the operation, the patient was treated in the ICU, a ventilator was installed,insulin was given to regulate blood sugar and anti-hypertension medication for maintaining blood pressure. During treatment in the ICU, adequate fluids and nutrition are provided. Monitoring is carried out on cardiovascular function, hemodynamics and respiration by monitoring blood pressure, electrocardiogram (ECG), oxygen saturation. The patient was moved to high care unit (HCU) after being treated for 3 days in the ICU.Conclusion: Postoperative therapy is more focused on supportive therapy, including maintaining the airway, regulating blood sugar, blood pressure and providing mechanical ventilation to maintain adequate oxygenation.