Ommaya Reservoir Placement Research Articles

PDOC-08 THE CLINICAL CHARACTERISTICS OF CHILDREN WITH CRANIOPHARYNGIOMA AND THEIR MANAGEMENT IN UGANDA: A RETROSPECTIVE REVIEW

Abstract BACKGROUND Craniopharyngiomas are benign brain tumors that mostly arise in the sellar/suprasellar region. Histologically though benign, these tumors can locally infiltrate with involvement of surrounding structures. They have a 5-year survival rate of above 80% in High Income Countries (HIC). Craniopharyngioma management includes surgery, radiotherapy and intracystic treatments, which requires a multi-disciplinary team. The morbidity associated with treatment must be weighed against tumor recurrence and quality of life after treatment. Endocrine deficiencies, especially growth hormone deficiency and visual deficits are common presenting features. OBJECTIVE To describe the clinical characteristics and management of children with craniopharyngioma managed at Mulago National Referral Hospital from March 2019 to December 2023. METHODOLOGY: A retrospective descriptive study was conducted among patients< 18 years of age, admitted to the Mulago National Referral Hospital (MNRH) from March 2019 to December 2023 with a radiological diagnosis of a craniopharyngioma. RESULTS A total of 151 children with a diagnosis of a brain tumor during this period were identified and of these 40 (26%) were diagnosed with craniopharyngioma. The median age was 8.4 years and 22 (55%) were males. Only 2 children had maximal safe resection (sub-total resection), one of whom later received adjuvant external beam radiotherapy. Thirty-eight patients had insertion of Ommaya reservoirs as their tumors were predominantly cystic. Two patients received intracystic bleomycin and 11 received radical external beam radiotherapy. Twenty-seven patients had no additional therapy after Ommaya reservoir placement. Fifteen (39%) of the patients had endocrine deficits with hypothyroidism, hypocortisolism and growth hormone deficiency being the most common. The median follow-up time was 1.45 years. The overall survival was 67.5%, 95%CI (42.5-83.5). CONCLUSION Management of patients with craniopharyngioma in Uganda is mostly conservative with the aim of intervention to preserve quality of life. Limited access to radiation therapy contributed to the poorer survival compared to HIC.

CP-08. THE CLINICAL CHARACTERISTICS OF CHILDREN WITH CRANIOPHARYNGIOMA AND THEIR MANAGEMENT IN UGANDA: A RETROSPECTIVE REVIEW

Abstract BACKGROUND Craniopharyngiomas are benign brain tumors that mostly arise in the sellar/suprasellar region. Histologically though benign, these tumors can locally infiltrate with involvement of surrounding structures. They have a 5-year survival rate of above 80% in High Income Countries (HIC). Craniopharyngioma management includes surgery, radiotherapy and intracystic treatments and requires a multi-disciplinary team. The morbidity associated with treatment must be weighed against tumor recurrence and quality of life after treatment. Endocrine deficiencies, especially growth hormone deficiency and visual deficits are common presenting features. OBJECTIVE To describe the clinical characteristics and management of children with craniopharyngioma managed at Mulago National Referral Hospital from March 2019 to December 2023. METHODOLOGY A retrospective descriptive study was conducted among patients< 18 years of age, admitted to the Mulago National Referral Hospital (MNRH) from March 2019 to December 2023 with a radiological diagnosis of a craniopharyngioma. RESULTS A total of 151 children with a diagnosis of a brain tumor during this period were identified and of these 40 (26%) were diagnosed with craniopharyngioma. The median age was 8.4 years and 22 (55%) were males. Only 2 children had maximal safe resection (sub-total resection), one of whom later received adjuvant external beam radiotherapy. Thirty-eight patients had insertion of ommaya reservoirs as their tumors were predominantly cystic. Two patients received intracystic bleomycin and 11 received radical external beam radiotherapy. Twenty-seven patients had no additional therapy after ommaya reservoir placement. Fifteen (39%) of the patients had endocrine deficits with hypothyroidism, hypocortisolism and growth hormone deficiency being the most common. The median follow-up time was 1.45 years. The overall survival was 67.5%, 95%CI(42.5-83.5). CONCLUSION Management of patients with craniopharyngioma in Uganda is mostly conservative with the aim of intervention to preserve quality of life. Limited access to radiation therapy contributed to the poorer survival compared to HIC.

Real-world use of a CSF circulating tumor cell assay in the diagnosis and management of leptomeningeal metastasis.

2029 Background: The diagnosis of leptomeningeal metastasis (LM) can be challenging due to variability in clinical symptoms, radiographic, and cerebrospinal fluid (CSF) findings. The National Comprehensive Cancer Network (NCCN) guidelines recommend assessment of circulating tumor DNA (ctDNA) to increase sensitivity of tumor cell detection and assess the response to treatment. We hypothesize that the real-world use of an assay for the direct detection and enumeration of circulating tumor cells (CTCs) in the CSF is clinically useful for accurate diagnosis of LM, particularly in an early stage of disease. Methods: We report a series of 55 patients treated at our institution with a cancer diagnosis and either neurological symptoms or radiographic findings that suggested LM. All patients underwent a lumbar puncture, assessment for CSF CTCs, and conventional hospital-based cytology testing between 6/1/2020 and 8/1/2023. Survival data cutoff was 12/31/2023. Patient outcomes are reported. Results: 55 patients were tested, and 30 patients were found to be positive for CTCs and diagnosed with LM. Only 10 patients were concurrently positive for CTCs and cytology at our institution, whereas 20 patients with positive CTCs had a negative or ambiguous cytology. No patients with a negative CTC result (25 patients) were subsequently diagnosed with LM, whereas 4 patients with a positive CTC result remained without progressive neurological symptoms. 5 patients diagnosed with LM were alive at the time of data cutoff. The histologic breakdown for LM was: breast (11), non-small cell lung cancer (NSCLC) (16), gastrointestinal (GI) (3). Median overall survival (OS) was longer in patients with a positive CTC and negative cytology result compared to patients with concurrent positive CTC and cytology (172 vs. 63 days, p = 0.06). Median OS was also longer in breast cancer LM compared to NSCLC LM (235 vs. 63 days, p = 0.008). Most patients diagnosed with LM received therapies including Ommaya reservoir placement, intrathecal chemotherapy, and/or radiation. Conclusions: The use of a CSF circulating tumor cell assay aided the diagnosis of LM and led to timely initiation of treatment. A negative result of the CTC assay was associated with ruling out LM. Diagnosis of LM with the CTC assay and negative cytology was associated with longer survival, possibly due to earlier treatment initiation, and not solely a lead time bias. Breast cancer LM patients had improved survival compared to NSCLC and GI cancer patients, possibly due to more effective treatment options.

Unlocking the Battle-Clipping vs. Endovascular Therapy for Shunt-Dependent Hydrocephalus After Aneurysm Rupture: An In-Depth Institutional Analysis.

To compare microsurgical clipping and endovascular therapy (EVT) for the management of shunt-dependent hydrocephalus (SDH) in patients with subarachnoid hemorrhage (SAH) and hydrocephalus. This retrospective study was conducted from July 2018 to December 2022 and included 67 patients with SAH accompanied by acute hydrocephalus. Patients' demographic, clinical, and radiological data, such as age, sex, Glasgow Coma Scale scores, Hunt and Hess scale, Fischer grade, external ventricular drain (EVD) duration, complications, Ommaya reservoir placement, cerebrospinal fluid drainage, and outcomes, were obtained. Statistical analyses, including univariate analysis and stepwise logistic regression, revealed significant risk factors for shunt dependence. Of the 67 patients, 33 underwent microsurgical clipping and 34 received EVT. Spasmolysis reduced shunt dependency, whereas early EVD placement correlated with reduced shunt dependence (p=0.002). The Ommaya reservoir helped in the management of meningitis but was found to be associated with shunt dependency (p=0.04). Multiple logistic regression analysis revealed that perioperative infarct was a significant risk factor for shunt dependence (p=0.05). No significant difference in patient outcomes was observed between the two treatment groups. However, patients who received EVT had shorter intensive care unit and hospital stays. This study shows that managing clinical vasospasm with spasmolysis may reduce shunt dependency. Overall, both microsurgical clipping and EVT offer similar long-term outcomes and efficacy in preventing shunt dependence, but the latter has the advantage of shorter hospital stay. These findings provide crucial insights for clinical decision-making and patient care in SDH after SAH.

Supraorbital minicraniotomy for open Ommaya reservoir placement in pediatric craniopharyngiomas: a case series and technical report.

Craniopharyngiomas with a predominant cystic component are often seen in children and can be treated with an Ommaya reservoir for aspiration and/or intracystic therapy. In some cases, cannulation of the cyst can be challenging via a stereotactic or transventricular endoscopic approach due to its size and proximity to critical structures. In such cases, a novel placement technique for Ommaya reservoirs via a lateral supraorbital incision and supraorbital minicraniotomy has been used. The authors conducted a retrospective chart review of all children undergoing supraorbital Ommaya reservoir insertion from January 1, 2000, to December 31, 2022, at the Hospital for Sick Children, Toronto. The technique involves a lateral supraorbital incision and a 3 × 4-cm supraorbital craniotomy, with identification and fenestration of the cyst under the microscope and insertion of the catheter. The authors assessed baseline characteristics and clinical parameters of surgical treatment and outcome. Descriptive statistics were conducted. A review of the literature was performed to identify other studies describing a similar placement technique. A total of 5 patients with cystic craniopharyngioma were included (3 male, 60%) with a mean age of 10.20 ± 5.72 years. The mean preoperative cyst size was 11.6 ± 3.7 cm3, and none of the patients suffered from hydrocephalus. All patients suffered from temporary postoperative diabetes insipidus, but no new permanent endocrine deficits were caused by the surgery. Cosmetic results were satisfactory. This is the first report of lateral supraorbital minicraniotomy for Ommaya reservoir placement. This is an effective and safe approach in patients with cystic craniopharyngiomas, which cause local mass effect but are not amenable to traditional Ommaya reservoir placement stereotactically or endoscopically.

Neuroendoscopic surgery combined with Ommaya reservoir placement for cystic craniopharyngiomas: 11 years of experience in a single institution

Introduction Total resection of cystic craniopharyngiomas is challenging, especially for some large cystic tumors, because it is often associated with high recurrence and morbidity rates. Minimally invasive cyst decompression and continuous drainage are appropriate to manage clinical symptoms. We reviewed our experience of the past 11 years to determine the long-term effects of neuroendoscopic surgery (NES) combined with Ommaya reservoir (OR) for the treatment of cystic craniopharyngiomas. Methods We retrospectively analyzed the data of 15 adult patients with cystic craniopharyngiomas at a single institution with the primary goal to evaluate the treatment mode with initial adequate decompression of the cyst under visualization and continuous drainage. The study endpoints were functional outcome, cyst volume changes, and tumor progression. Results The median follow up was 77 (20–136) months. Clinical symptoms, e.g. increased intracranial pressure and visual impairment, could be rapidly improved after NES. The postoperative reduction in cyst volume (p < 0.001) and improvement in Karnofsky performance status (p < 0.001) were significant, and long-term tumor control was achieved in 10 patients (67%). Aspiration from the OR after progression of the tumor’s cystic portion remains a major option, with only few patients requiring repeat NES procedures. No patient developed acute or severe clinical symptoms during follow up. Conclusions NES could decompress the craniopharyngioma cyst under visualization and enable faster clinical-symptom improvement. The minimally invasive NES combined with OR allowed long-term symptom control in most patients without surgery-related injury. This palliative treatment strategy could be an alternative modality for cystic craniopharyngioma treatment.

QLTI-17. PROPHYLACTIC VANCOMYCIN REDUCES OMMAYA RESERVOIR-ASSOCIATED BACTERIAL MENINGITIS: A 12-MONTH PROSPECTIVE STUDY

Abstract INTRODUCTION Intraventricular chemotherapy administered through an Ommaya reservoir (OR) constitutes the mainstay of therapy for adults with leptomeningeal metastases from solid and hematologic malignancies. Unfortunately, OR-associated bacterial meningitis remains a relatively frequent, costly, often morbid, and occasionally fatal complication, limiting the benefit of this approach. We investigated the potential efficacy, cost savings, and toxicity of intraventricular vancomycin co-administered with intraventricular chemotherapy. METHODS Detailed demographic, treatment, and outcome data were collected prospectively between 5/1/21 and 4/30/22 for 63 consecutive patients at our institution who underwent OR placement and subsequent intraventricular chemotherapy, co-administered with 10 mg of intraventricular vancomycin at each treatment. Reservoir-associated bacterial meningitis was defined as 2 consecutive positive cultures from the cerebrospinal fluid of the same organism or 1 positive culture in the presence of any other clinical or laboratory evidence of infection, or signs of infection at the surgical site. RESULTS The infection rate was 0% [95% CI 0-6.75%] among the 63 patients and 0% [0-0.76%] in the 501 consecutive treatments administered over the 12-month study period compared to 10.25% [7.39- 14.0%] in 322 patients and 1.71% [1.22-2.39%] in 1932 treatments over the preceding 5 years. The absolute risk reduction was 10.3% [3.83 - 14.04], p = 0.0049. The number needed to treat was 10 [7-26]. Cost per vancomycin dose was $10.00 ($5,010 over 12 months). The cost of non-surgical treatment of one OR-associated infection is $88,337.70, which translates into a $618,363.90 savings for the estimated 7 patients over 12 months spared an OR-associated infection. Savings were even further increased if OR removal and subsequent replacement was required. The only other covariate associated with (increased) infection risk on multivariable analysis was treatment number. No treatment-associated toxicity was observed. CONCLUSION Prophylactic intraventricular vancomycin eliminated OR-associated infection in patients receiving intraventricular chemotherapy. Dramatic cost savings were achieved without added toxicity.

DDEL-02. LUMBAR OMMAYA RESERVOIR- A COST EFFECTIVE ALTERNATIVE TO INTRAVENTRICULAR OMMAYA RESERVOIR FOR TREATMENT OF LEPTOMENINGEAL DISEASE

Abstract Introduction Lumbar puncture (LP) is a well-established approach for intrathecal (IT) delivery of chemotherapeutics for leptomeningeal disease (LMD). Intraventricular Ommaya reservoir (OR) has supplanted LPs as an easier and safer route for IT administration. Radiotherapy for treatment of LMD must be delayed in order for surgical wound healing following OR placement. Furthermore, prior cranial radiation can thin the scalp, predisposing to wound breakdown. Placement of lumbar Ommaya reservoir (LOR) provides an alternative to IT delivery, but this has not reached a wide-spread acceptance. Objective Provide cost-analysis and report patient outcomes after placement of LOR. METHODS Following IRB approval, all patients undergoing LOR placement between 2018 and 2020 were retrospectively reviewed. Patients age, primary tumor, survival lengths and complications were reviewed. Average procedure-related treatment cost was obtained from an uncomplicated representative case excluding the surgeon’s fee. RESULTS Fourteen patients (mean age 46.35 years) were identified. The mean follow-up was 440.7 (25-1003) days post-surgery. Acute lymphoblastic leukemia (n = 4), acute myeloblastic leukemia (n = 3), breast carcinoma (n = 3), ependymoma (n = 3), lymphoma (n = 2) and lung adenocarcinoma (n = 1) were identified as underlying malignancy. LMD was diagnosed on average after 581.1 days after the diagnosis of the underlying malignancy. 8 patients succumbed to their malignancy on average after 463.9 and 314.6 days after the diagnosis of LMD and LOR surgery, respectively. There were 2 complications – pain at the site of the LOR and a fractured catheter caused by inadvertent puncture of the catheter. No infections or wound healing complications were noted. Typical cost for placement of LOR and OR was – 17,350 USD and 29,052 USD, respectively. Placement of the LOR proved to be more cost-effective in this cohort by approximately 40% cost reduction. CONCLUSION Placement of LOR is a cost effective alternative to cranial OR with low complication profile, and well tolerated by patients.

Ommaya Reservoir and the External Ventricular Drainage

Childhood hydrocephalus is a highly diverse disease caused by various factors, and most surgical treatments are performed during infancy. Despite the diversity of hydrocephalus pathologies, treatment options are limited. It is difficult for pediatric neurosurgeons to select and perform appropriate surgical procedures for neonates and infants. Treatment options for hydrocephalus are broadly divided into permanent and temporary. Permanent treatments include cerebrospinal fluid shunt and endoscopic third ventriculostomy; temporary treatment entails cerebrospinal fluid drainage using lumbar puncture and intermittent cerebrospinal fluid drainage with an Ommaya reservoir, ventricular drainage, and ventriculosubgaleal shunt. This article describes in detail Ommaya reservoir placement and ventricular drainage as representative procedures for temporarily treating hydrocephalus.

Role of Ommaya Reservoir Placement in Hydrocephalus Management following Aneurysmal Subarachnoid Hemorrhage, an Initial Experience

Abstract Introduction Weaning from external ventricular drainage (EVD) of cerebrospinal fluid (CSF) in hydrocephalus induced by aneurismal subarachnoid hemorrhage (SAH) had been proposed either through the rapid, gradual or intermittent approaches. There are no uniform guidelines for it. Given this, we planned to study the comparative outcome between EVD drainage with intermittent clamping versus EDV followed by Ommaya reservoir. Material and Methods The present retrograde observational study was conducted from July 2018 to March 2021 in the department of neurosurgery with 67 patients who developed hydrocephalus following SAH after aneurysm rupture. We divided the patients into two groups. Group 1 had only EVD placed for CSF drainage with intermittent clamping before the placement of the ventriculoperitoneal (VP) shunt, and, in group 2, an Ommaya reservoir was placed after EVD before the shunt. Result There were 38 patients in group 1 and 29 in group 2. They were age-matched, with a mild male predominance in group 1. Shunt dependency was significantly reduced in group 2 patients (p = 0.011), along with reduced length of stay in ICU (p = 0,001) and length of stay in Hospital (p = 0.019). We found improved Glasgow outcome score in group 2 patients (p = 0.006) together with reduced incidence of infarct (p = 0.0095). Conclusion We may infer from the present study that continuous drainage through EVD, initially, in hydrocephalus induced by SAH following aneurysm rupture, increases cerebral perfusion pressure (CPP) and decreases intracranial pressure (ICP) leading to decreased infarct rate and intermittent drainage through Ommaya following EVD reservoir, decreases shunt dependency, reduces ICU and hospital stay, with improved Glasgow outcome score on follow-up, but these findings need to be validated in a prospective randomized control trial.

RARE-30. Novel collision tumor of craniopharyngioma and ependymoma in a pediatric patient: a case study

Abstract Collision tumors are rare tumors comprised of two distinct histologies. In this case report, we discuss a suprasellar collision tumor consisting of adamantinomatous craniopharyngioma and supratentorial ependymoma in a pediatric patient. Case Presentation: Our patient was a two-year-old female with progressive craniopharyngioma status post cyst decompression with Ommaya reservoir placement, subcutaneous peginterferon, Ommaya taps, and subtotal resection. An MRI three months post-resection showed progression and treatment was started with subcutaneous interferon alfa. After eight weeks, she presented with new onset headaches and vomiting. MRI demonstrated tumor progression with associated obstructive hydrocephalus. She underwent a subtotal resection. Pathology revealed recurrent adamantinomatous craniopharyngioma and a 0.5cm ependymoma with classic histomorphology lacking anaplasia features. The ependymoma was positive for GFAP immunostain and EMA immunohistochemistry highlighted a ‘dot-like’ reaction. The Ki-67 proliferation index was very low (&amp;lt;1%). The limited diagnostic material precluded further genomic characterization of the ependymoma. The previous pathology was reviewed and no ependymoma was identified. Spine MRI was negative for metastatic disease. CSF cytology was negative for malignant cells. Following recovery from surgery, she received 54Gy (RBE) focal proton radiation. Eight months from completion of therapy, surveillance MRI shows stable residual tumor. Genetic work-up for cancer predisposition syndrome is in process despite no strong family history of cancer. Discussion: Due to the patient’s young age at diagnosis, our initial treatment strategy was to delay radiotherapy and utilize other treatment options. Following diagnosis with a collision tumor, the patient proceeded to radiotherapy to manage both tumor components. The role of interferon in the development of a collision tumor in this patient in unknown, but we suspect it to be unrelated. Conclusion: To our knowledge, this is the first documented case of a suprasellar collision tumor comprised of craniopharyngioma and ependymoma. Discovery of the collision tumor impacted the patient’s treatment plan.

Cryptococcal Meningitis with Inadequate Response to Antifungal Therapy or Drug-Induced Side Effects That Make It Difficult to Continue Treatment: Eleven Clinical Issues in Medical Practice

Cryptococcal meningoencephalitis is mainly caused by Cryptococcus neoformans and accounts for 90% of fungal meningitis cases in Japan. Cryptococcal meningoencephalitis is a rare disease, and similar to tuberculosis meningitis. It often exhibits subacute or chronic progression symptoms such as headache, fever, coma, personality changes, and memory disturbance. Cryptococcal meningoencephalitis often develops in immunosuppressed hosts, but can sometimes occur in healthy individuals, and the mortality rate is 10-25%, indicating a poor prognosis. For the treatment of cryptococcal meningoencephalitis, introduction therapy using a combination of liposomal amphotericin B and flucytosine is recommended. However, in practice, cryptococcal meningoencephalitis is refractory and often requires prolonged treatment; therefore, it is the most difficult to treat among the central nervous system infections. We discuss the following 11 issues: I. Sustainability of first-line treatments, II. Treatment options in case of decreased renal function, III. Association with increased intracranial pressure IV. Causes of visual impairment, V. Necessary steps when symptoms/laboratory findings worsen during antifungal treatment, VI. Cerebral infarction, VII. Difficulty in controlling underlying and comorbid diseases, VIII. Indications for lumbar and ventricular drainage (Ommaya reservoir placement), IX. Pros and cons of concomitant use of corticosteroids, X. Treatment evaluation index: usefulness of head MRI, and XI. Determining the end of treatment and the need for preventive medication.

Evaluation of Pediatric Hydrocephalus: Clinical, Surgical, and Outcome Perspective in a Tertiary Center.

Context:Pediatric hydrocephalus (PH) results in significant clinical and psychosocial morbidity in pediatric population.Aims:The aims of the study are to evaluate clinical, surgical, and outcome perspective of PH patients of age <12 years.Settings and Design:This is a retrospective cohort study.Materials and Methods:This study includes 117 pediatric patients (age ≤12 years) of hydrocephalus due to various etiology admitted in our department between September 2018 and December 2020. Demographic profile, etiology, clinical presentation, management, complications and postoperative outcome characteristics were evaluated. Survival analysis was done with respect to etiology and age group.Statistical Analysis Used:P < 0.05 was considered statistically significant. Unpaired t-test and Chi-square test were used. Kaplan–Meier curve plotting and survival analysis were also done.Results:Male-to-female ratio was 1.3:1. Most frequent etiology of PH was postinfectious (35%). Posterior fossa pilocytic astrocytoma (34.2%) was the most common neoplastic etiology. Surgical procedure performed for PH was ventriculoperitoneal shunting (n = 103), Ommaya reservoir (n = 2) placement, and endoscopic third ventriculostomy (ETV) (n = 8). Mortality was significantly (P = 0.0139) more in patients of neoplastic etiology. Cognitive deficits and delayed developmental milestones were significantly (P < 0.05) more in congenital hydrocephalus etiology. There was a nonsignificant difference in survival between age groups (P = 0.1971). However, a significant survival difference was evident (P = 0.0098) for etiology.Conclusions:Disease-specific mortality is main cause of mortality in PH. Neoplastic etiology PH has poor survival when compared to others. Life-long routine controls are required to avoid future possible complications and enhance better rehabilitation of the child.

Versatile Use of Intraoperative Ultrasound Guidance for Brain Puncture.

Intraoperative ultrasound (iUS) is an effective guidance and imaging system commonly used in neuro-oncological surgery. Despite the versatility of iUS, its utility for single burr hole puncture guidance remains fairly underappreciated. To highlight the simplicity, versatility, and effectiveness of iUS guidance in brain puncture by presenting the current case series and technical note collection. We present 4 novel uses of iUS guidance for single burr hole brain puncture: cannulation of normal-sized ventricles, endoscopic third ventriculostomy (ETV) guidance, evacuation of interhemispheric empyema, and stereotactic biopsy assistance. All techniques were performed successfully in a total of 16 patients. Normal-sized ventricles were cannulated in 7 patients, among whom 5 underwent Ommaya reservoir placement and 2 underwent ventriculoperitoneal shunt placement for idiopathic intracranial hypertension. No more than 1 attempt was needed for cannulation. All ventricular tip positions were optimal as shown by postoperative imaging. iUS guidance was used in 5 ETV procedures. The working cannula was successfully introduced to the lateral ventricle, providing the optimal trajectory to the third ventricular floor in these cases. Interhemispheric subdural empyema was aspirated with iUS guidance in 1 patient. Volume reduction was clearly visible, allowing near-total evacuation of the empyema. iUS guidance was used for assistive purposes during stereotactic biopsy in 3 patients. No major perioperative complications were observed throughout this series. iUS is an effective and versatile guidance system that allows for real-time imaging and can be easily and safely employed for various brain puncture procedures.

P14.26 Leptomeningeal Disease Secondary to Melanoma: Diagnosis, Treatment, and Outcomes at a Single Institution between 2013 and 2019

Abstract BACKGROUND Leptomeningeal disease (LMD) is devastating with a median survival of only 8–10 weeks. LMD affects approximately 5% to 25% of melanoma patients. Its pathophysiology remains unknown and effective treatments are virtually non-existent. The aim was to evaluate demographics, validity of Veridex CellSearch® System (VCS) compared to Gold Standard test (i.e., CSF cytology), risk factors for LMD, and treatment outcomes. MATERIALS AND METHODS A retrospective chart review was performed of subjects with suspected LMD from melanoma enrolled in the MCC 19332/19648 studies between 2013 and 2019 at Moffitt Cancer Center. The patients underwent standard of care with different treatments as deemed appropriate by treating physician. CSF samples were obtained from lumbar punctures, surgeries, and Ommaya reservoir, and sent for analysis. Peripheral blood and CSF were evaluated for detection and quantification of CSF circulating tumor cells (CTCs) with the Veridex CellSearch® System, which is adapted to enumerate CTCs from CSF. RESULTS More than 100 patient charts were reviewed. Only patients with melanoma as primary tumor (N=48) were included in the analysis, with ages 29–80. N=28 (58%) met criteria for LMD (median age 59, M:F ratio of 3:1). Within the LMD group, n=26 patients had cutaneous melanoma as primary tumor; BRAF mutant n=17 (V600E n=14; G469E n=1). At the time of diagnosis, median KPS score was 70, with most prevalent symptoms of headaches, encephalopathy, focal weakness, and nausea/vomiting. N=20 (71%) patients were diagnosed radiographically and n=5 (18%) with CSF cytology; n=14 (52%) had positive cytology on first LP, n=18 (67%) on first two LPs. From 25 patients with LMD who underwent CellSearch® to quantify CTCs, n=22 (88%) patients had positive CSF CTCs; n=18 (72%) on first sample sent for analysis, n=20 (80%) on first two samples. The sensitivity and specificity of the Veridex CellSearch® System compared to the Gold Standard CSF cytology were analyzed. Survival in months plotted against the percentage of CSF-CTCs showed a significant value of p=0.0377. CSF analysis i.e., inflammatory markers, and treatments pre-/post-LMD diagnosis will be described. Most patient were managed with Ommaya reservoir placement, radiation therapy, immunotherapy, BRAF +/- MEK inhibitors, IT thiotepa, or IT topotecan. The median survival of those with LMD was 3.15 months. Two patients outlived their counterparts by 21.1 and 39.0 months after the LMD diagnosis, one of them is still alive but with a very poor functional status. CONCLUSION These results indicate the potential value of the VCS as an additional tool to the gold standard in the diagnosis of LMD in patients with high suspicion of the disease. Future directions involve doing prospective studies to further validate this method, and to better understand this patient population to enhance diagnostic tools and management of LMD.

Postoperative 30-day emergency department utilization after 7294 cranial neurosurgery procedures at a tertiary neuroscience center.

Hospital readmission and the reduction thereof has become a major quality improvement initiative in organized medicine and neurosurgery. However, little research has been performed on why neurosurgical patients utilize hospital emergency rooms (ERs) with or without subsequent admission in the postoperative setting. This study was a retrospective, single-center review of data for all surgical cranial procedures performed from July 2013 to July 2016 in patients who survived to discharge. The study was approved by the institutional review board of the participating medical center. The authors identified 7294 cranial procedures performed during 6596 hospital encounters in 5385 patients. The rate of postoperative ER utilization within 30 days after surgical hospitalization across all procedure types was 13.1 per 100 surgeries performed. The two most common chief complaints were pain (30.7%) and medical complication (18.2%). After identification of relevant surgical and patient factors with univariable analysis, a multivariable backward elimination logistic regression model was constructed in which Ommaya reservoir placement (OR 2.65, p = 0.0008) and cranial CSF shunt placement (OR 1.40, p = 0.0001) were associated with increased ER utilization. Deep brain stimulation electrode placement (OR 0.488, p = 0.0004), increasing hospital length of stay (OR 0.935, p < 0.0001), and increasing patient age (OR 0.988, p < 0.0001) were associated with lower rates of postoperative ER utilization. One-half (50%) of ER visit patients were readmitted to the hospital. New/worsening neurological deficit chief complaint (OR 1.99, p = 0.0088), fever chief complaint (OR 2.41, p = 0.0205), altered mentation chief complaint (OR 2.71, p = 0.0002), patient chronic kidney disease (OR 3.31, p = 0.0037), brain biopsy procedure type (OR 3.50, p = 0.0398), and wound infection chief complaint (OR 31.4, p = 0.0008) were associated with increased rates of readmission to the hospital from the ER in multivariable analysis. The authors report the rates of and reasons for ER utilization in a large cohort of postoperative cranial neurosurgical patients. Factors identified were associated with both increased and decreased use of the ER after cranial surgery, as well as variables associated with readmission to the hospital after postoperative ER visitation. These findings may direct future quality improvement via prospective implementation of care pathways for high-risk procedures.

How I do it: ultrasound-guided placement of ommaya reservoir in a patient with small ventricles and cavum septum pellucidum.

Intraventricular chemotherapy via Ommaya reservoir is an important part of the treatment in patients with malignant central nervous system tumors. In these patients, catheter placement can be challenging due to the normal-sized ventricles. Intraoperative ultrasound guidance was used for Ommaya reservoir placement in a 56-year-old patient with multiple intracranial and leptomeningeal metastases who had cavum septum pellucidum et vergae malformation. The catheter was successfully placed into the frontal horn of the lateral ventricle outside the cavum. Intraoperative ultrasound is a suitable image guidance system in patients with slit-like or normal-sized ventricles. It can also be used in patients with ventricular malformations.

LINC-23. PRE-OPERATIVE AND POST-OPERATIVE INTERVENTIONS REDUCE RATES OF VENTRICULITIS IN PEDIATRIC BRAIN TUMOR PATIENTS: A PILOT STUDY

BACKGROUNDThe Philippine General Hospital, a public national referral center, sees 60–80 pediatric brain tumor cases per year. Historically, the rate of post-operative ventriculitis has been high, resulting in treatment delays and poor outcomes. Starting in July 2019, as a means to decrease infections, patients were provided standardized bathing and wound care kits and caregivers were trained to follow a bathing and wound care protocol.METHODSThis quality improvement study included patients younger than 18 years who underwent craniotomy at PGH were enrolled. The type of surgery, length of surgery, existence of post-operative CNS infection, length of stay and total cost of care was collected. The outcome of these interventions are analyzed 6 months after implementation.RESULTSThirty-two 32 patients were included, with mean age of 7 years (1–16). The surgeries performed were: tumor resection (n=20), ventriculo-peritoneal shunt insertion (VPS) (n=3), endoscopic third ventriculostomy (n=3), resection with tube ventriculostomy (n=3), Ommaya reservoir placement (n=2), and resection with shunt (n=1). Median surgery time was 4 hours (1–10). Three patients (9.4%) developed ventriculitis. No surgical site infections occurred. Compared to historical controls, a lower rate of infections was noted (9.4% vs. 15.5%, runchart analysis). Patients without post-operative infections had a shorter length of stay (median 14 vs 48 days, p<0.05) and a lower cost of care (median $1098 vs. $2425 USD, p<0.05).CONCLUSIONImplementation of simple hygiene interventions effectively lowered post-operative CNS infections and hospital costs in a public hospital setting. Incorporation of these into standard clinical practices is urgently needed.

Delayed subdural fluid collections after Ommaya reservoir placement.

Delayed subdural fluid collections can occur after Ommaya reservoir placement and can cause neurological symptoms and interfere with treatment. We performed a retrospective chart review to study risk factors for delayed subdural fluid collections and clinical outcomes. Retrospective chart review was performed for patients undergoing Ommaya reservoir placement between 2010-2019 at our institution. Out of 53 patients who had Ommaya reservoir placement during the study period, 11 developed delayed subdural fluid collections (21%). HIV infection was the only statistically significant risk factor (P=0.001, Fisher's Exact Test). Thrombocytopenia, ventricle size, use of the reservoir, and suboptimal catheter placement were not associated with development of delayed subdural fluid collections. 2 patients, both HIV positive, required surgical evacuation. Delayed subdural fluid collections occur in a significant minority of patients after Ommaya reservoir placement, and some patients require surgical intervention. HIV infection is associated with a higher risk of development of delayed subdural fluid collections. This patient subpopulation may benefit from closer monitoring or adjustment of management protocols.

Endoscopic Third Ventriculostomy and Simultaneous Tumor Biopsy in Pineal Region Tumors using the "Single Burr Hole" Technique: An Analysis of 34 Cases.

Background:Pineal region tumors often present with hydrocephalus. Endoscopic third ventriculostomy (ETV) and simultaneous tumor biopsy remain a minimally invasive procedure offering both diagnostic and therapeutic advantages in the management of these tumors. However, different operative techniques have been described in the literature.Aim:The aim is to study the ETV success rate, diagnostic rate of simultaneous tumor biopsy, complications, and follow-up of patients of pineal region tumors managed with ETV and simultaneous tumor biopsy using the single burr hole technique.Methods:The study was performed by retrospectively reviewing the records of patients of pineal region tumors managed by simultaneous ETV and tumor biopsy using a “single burr hole” technique from January 2012 to December 2019.Results:Thirty-four patients (22 males and 12 females) with a mean age of 28.7 years were analyzed. ETV was successful in relieving hydrocephalus in 29 (87.8%) patients. Three patients needed a ventriculoperitoneal shunt, and one required Ommaya reservoir placement for persistent hydrocephalus. Histological diagnosis was successfully established in 26 (78.8%) patients. There were two procedure-related mortalities. Two patients underwent craniotomy and tumor excision subsequently. Radiotherapy was given to 11 patients, and 9 patients were managed by observation alone. The mean follow-up of our study was 15.8 months.Conclusions:Simultaneous ETV and tumor biopsy using a single burr hole technique is a safe, minimally invasive procedure for the management of pineal region tumors.