Intracranial Hypertension with Patent Basal Cisterns: Controlled Lumbar Drainage as a Therapeutic Option. Selected Case Series.

BACKGROUND: There are pathological conditions in which intracranial hypertension and patent basal cisterns in computed tomography coexist. These situations are not well recognized, which could lead to diagnostic errors and improper management. METHODS: We present a retrospective case series of patients with traumatic brain injury, subarachnoid hemorrhage, and cryptococcal meningitis who were treated at our intensive care unit. Criteria for deciding placement of an external lumbar drain were (1) intracranial hypertension refractory to osmotherapy, hyperventilation, neuromuscular blockade, intravenous anesthesia, and, in some cases, decompressive craniectomy and (2) a computed tomography scan that showed open basal cisterns and no mass lesion. RESULTS: Eleven patients were studied. Six of the eleven patients treated with controlled lumbar drainage are discussed as illustrative cases. All patients developed intracranial hypertension refractory to maximum medical treatment, including decompressive craniectomy in Four of the eleven cases. Controlled external lumbar drainage led to immediate and sustained control of elevated intracranial pressure in all patients, with good neurological outcomes. No brain herniation, intracranial bleeding, or meningitis was detected during this procedure. CONCLUSIONS: Our study provides preliminary evidence that in selected patients who develop refractory intracranial hypertension with patent basal cisterns and no focal mass effect on computed tomography, controlled lumbar drainage appears to be a therapeutic option. In our study there were no deaths or complications. Prospective and larger studies are needed to confirm our results.

Classifications of hydrocephalus based on Walter Dandy and his paradigm.

PURPOSE: The purpose of this review is to assess the early work of Walter Dandy leading to a paradigm or model that led to the first classification of hydrocephalus and resulted in the development of treatments. METHODS: The modern understanding of hydrocephalus begins with the works of Walter Dandy. The purpose of this review is to discuss what was changed in the second decade of the 20th century and how the outcome is useful today. As a result of his experiments during that time he was able to recognize the role of the choroid plexus in the production of cerebrospinal fluid (CSF) within the cerebral ventricles. He then identified the role of obstruction blocking the flow of CSF from the ventricles to the absorption of CSF to the systemic vascular. As a result of those findings he showed that there were two forms of hydrocephalus and therefore the first classification of hydrocephalus into obstructive hydrocephalus and communicating hydrocephalus. Very soon after the publication of the experiments there was general agreement of this work by neurosurgeons working on hydrocephalus. The findings published in "experimental hydrocephalus" became a paradigm useful for all or the vast percentage of those neurosurgeons. RESULTS: Dandy was the first to create a classification of hydrocephalus into obstructive and communicating hydrocephalus. He developed treatments for hydrocephalus such as removal of the choroid plexuses that remained in use until effective valved shunts became available in the 1950s. Essentially all subsequent classifications begin with this paradigm. CONCLUSION: Over time there have been new classifications primarily focused on specific uses. It is important that classifications in the sciences be reviewed periodically to include new findings and new ideas. Since the expectation that hydrocephalus can be treated or even cured new classifications tend to focus on the physics of CSF, the choice of treatment and the outcome in specific subgroups. These thoughts should be seen as additions to the paradigm.

Long term outcome after surgical treatment for hypothalamic hamartoma.

PURPOSE: To determine long-term outcome for seizure control and clinical predictors for seizure freedom in patients undergoing surgical treatment for epilepsy associated with hypothalamic hamartoma (HH). METHODS: 155 patients underwent surgical treatment for HHs and treatment-resistant epilepsy at one center (Barrow Neurological Institute at St. Joseph's Hospital and Medical Center, Phoenix, Arizona, USA) between February 2003 and June 2010. Data collection included medical record review and direct follow-up interviews to determine seizure outcome. Statistical analysis included descriptive summaries of patient characteristics and time-to-event analysis for seizure freedom. RESULTS: Long-term survival with follow-up of at least five years since first surgical treatment was available for 108 patients (69.7% of the treatment cohort). The surgical approach for first HH intervention consisted of transventricular endoscopic resection (n = 57; 52.8%), transcallosal interforniceal resection (n = 35; 32.4%), pterional resection (n = 7; 6.5%), and gamma knife radiosurgery (n = 9; 8.3%). Multiple surgical procedures were required for 39 patients (36.1%). There were 10 known deaths from all causes in the treatment cohort (6.5%). Of these, one (0.6%) was related to immediate complications of HH surgery, three (1.9%) were attributed to Sudden Unexpected Death in Epileptic Persons (SUDEP), and one (0.6%) to complications of status epilepticus. For surviving patients with long-term follow-up, 55 (50.9%) were seizure-free for all seizure types. Univariable analysis showed that seizure-freedom was related to 1) absence of a pre-operative history for central precocious puberty (p = 0.01), and 2) higher percentage of HH lesion disconnection after surgery (p = 0.047). Kaplan-Meier survival analysis shows that long-term seizure outcome following HH surgery is comparable to short-term results. SUMMARY: These uncontrolled observational results show that long-term seizure control following HH surgical treatment is comparable to other forms of epilepsy surgery. Late relapse (at least one year after surgery) and SUDEP do occur, but in a relatively small number of treated patients. These results inform clinical practice and serve as a comparable benchmark for newer technologies for HH surgery, such as magnetic resonance imaging-guided laser interstitial thermal therapy, where long-term outcome results are not yet available.

Microsurgical Management of Complex Hypothalamic Hamartomas in the Era of Minimally Invasive Therapy: A Case Series and Narrative Review.

BACKGROUND: There has been a paradigm shift in the management of hypothalamic hamartoma (HH) from traditional microsurgical techniques to less invasive alternatives. However, large and extensive HH may fail to respond to these therapies, necessitating craniotomies. METHODS: All patients who underwent microsurgical resection of a complex HH by the 2 senior authors from 2011 to 2021 were included. Charts were retrospectively reviewed and demographic, clinical, imaging, and outcome data were recorded. RESULTS: Eight patients (mean age, 7 years) were included. Two had failed previous treatments. All 7 presented with gelastic seizures and cognitive dysfunction, 6 showed central precocious puberty, and 3 had behavioral problems. The mean lesion size was 21.6 mm and all had interpeduncular extension, 5 had intraventricular extension (Delalande type I, 3; type III, 4; type IV, 1). A frontotemporal orbitozygomatic approach with optic nerve decompression was used in all patients, supplemented by another approach in 3 (endoscopic transventricular, 3; transcallosal, 1). Gross total resection was achieved in 6 patients and subtotal resection in 2. Transient complications occurred in 3 patients (37.5%): self-limited sodium imbalance (n = 3), subdural hygroma (n = 2). Permanent complications occurred in 2 patients (25%): perforator infarct (n = 1) and short-term memory loss (n = 1). All patients experienced seizure resolution with preserved hypothalamic-pituitary axis function. After a mean follow-up of 41 months (range, 2-66 months), 7 patients remained seizure free, and 1 had rare seizures. Cognitive and behavioral symptoms improved in all patients. CONCLUSIONS: For large HH with interpeduncular extension, microsurgery via the frontotemporal orbitozygomatic approach is a safe and highly effective treatment modality.

Long-term telemetric intracerebral pressure monitoring as a tool in intracranial hypotension.

Intracranial hypotension (IH) remains a difficult neurosurgical diagnosis. Relying solely on the symptomatology may be misleading for both diagnosis and assessment of treatment effect as symptoms may resemble other conditions not related to IH. As such, paraclinical supplements in both diagnosis and treatment follow-up are warranted. We present a 42-year-old male with IH treated with computed tomography-guided epidural blood patch. The diagnosis and treatment assessment included continual intracerebral pressure (ICP) monitoring. We found ICP monitoring helpful in IH diagnosis and long-term assessment of treatment and propose this modality as a supplement in difficult IH cases.

Hydrocephalus in infants: the unique biomechanics and why they matter.

OBJECT: Hydrocephalus diagnosed prenatally or in infancy differs substantially from hydrocephalus that develops later in life. The purpose of this review is to explore hydrocephalus that begins before skull closure and full development of the brain. Understanding the unique biomechanics of hydrocephalus beginning very early in life is essential to explain two poorly understood and controversial issues. The first is why is endoscopic third ventriculostomy (ETV) less likely to be successful in premature babies and in infants? The second relates to shunt failure in a subset of older patients treated in infancy leading to life-threatening intracranial pressure without increase in ventricular volume. METHODS: The review will utilize engineering concepts related to ventricular volume regulation to explain the unique nature of hydrocephalus developing in the fetus and infant. Based on these concepts, their application to the treatment of complex issues of hydrocephalus management, and a review of the literature, it is possible to assess treatment strategies specific to the infant or former infant with hydrocephalus-related issues throughout life. RESULTS: Based on engineering, all hydrocephalus, except in choroid plexus tumors or hyperplasia, relates to restriction of the flow of cerebrospinal fluid (CSF). Hydrocephalus develops when there is a pressure difference from the ventricles and a space exterior to the brain. When the intracranial volume is fixed due to a mature skull, that difference is between the ventricle and the cortical subarachnoid space. Due to the distensibility of the skull, hydrocephalus in infants may develop due to failure of the terminal absorption of CSF. The discussion of specific surgical treatments based on biomechanical concepts discussed here has not been specifically validated by prospective trials. The rare nature of the issues discussed and the need to follow the patients for decades make this quite difficult. A prospective registry would be helpful in the validation of surgical recommendations. CONCLUSION: The time of first intervention for treatment of hydrocephalus is an important part of the history. Treatment strategies should be based on the assessment of the roll of trans-mantle pressure differences in deciding treatment strategies. Following skull closure distension of the ventricles at the time of shunt failure requires a pressure differential between the ventricles and the cortical subarachnoid space.

Pathogenesis of hydrocephalus in achondroplastic dwarfs: a review and presentation of a case followed for 22 years.

OBJECT: The purpose of this work is to review the pathogenesis and pathophysiology of hydrocephalus in patients with achondroplasia as a guide to its management throughout life. METHODS: A review of the literature related to neurosurgical issues in achondroplasia with specific focus on cerebrospinal fluid physics, clinical management, and outcome of affected individuals. Issues involved in this review are highlighted by a case report of a patient shunted for achondroplasia first shunted in infancy and followed for 22 years. Each of the management issues is explored with respect to this patient. FINDINGS: Head circumferences in achondroplasia are abnormally large in this condition usually caused by excess cerebrospinal fluid in the cortical subarachnoid space. Increase in ventricular size (hydrocephalus) is not rare but should not be treated unless rapidly progressive or symptomatic. The underlying cause of the abnormalities of cerebrospinal fluid dynamics relates to abnormal venous drainage at the skull base. Patients shunted in infancy for hydrocephalus usually remain dependent on the shunt for life, and crises of high intracranial pressure may occur with no distention of the ventricles. CONCLUSIONS: In infants with achondroplasia, large heads and enlarged ventricles without symptoms should be watched initially for progression. If hydrocephalus progresses or if symptoms of intracranial hypertension occur, endoscopic third ventriculostomy can be tried. If shunt is necessary, it should have a high opening pressure and a device to retard siphoning. In the case of recurrent ventricular catheter blockage, it may be necessary to create a communication between the ventricles and the cortical subarachnoid space.

Successful endoscopic third ventriculostomy in children depends on age and etiology of hydrocephalus: outcome analysis in 51 pediatric patients.

PURPOSE: Endoscopic third ventriculostomy (ETV) has become the method of choice in the treatment of hydrocephalus. Age and etiology could determine success rates (SR) of ETV. The purpose of this study is to assess these factors in pediatric population. METHODS: Retrospective study on 51 children with obstructive hydrocephalus that underwent ETV was performed. The patients were divided into three groups per their age at the time of the treatment: < 6, 6-24, and > 24 months of age. All ETV procedures were performed by the same neurosurgeon. RESULTS: Overall SR of ETV was 80% (40/51) for all etiologies and ages. In patients < 6 months of age SR was 56.2% (9/16), while 6-24 months of age was 88.9% (16/18) and > 24 months was 94.1% (16/17) (p = 0.012). The highest SR was obtained on aqueductal stenosis. SR of posthemorrhagic, postinfectious, and spina bifida related hydrocephalus was 60% (3/5), 50% (1/2), and 14.3% (1/7), respectively. While SR rate at the first ETV attempt was 85.3%, it was 76.9% in patients with V-P shunt performed previously (p = 0.000). CONCLUSIONS: Factors indicating a potential failure of ETV were young age and etiology such as spina bifida, other than isolated aqueductal stenosis. ETV is the method of choice even in patients with former shunting. Fast healing, distensible skulls, and lower pressure gradient in younger children, all can play a role in ETV failure. Based on our experience, ETV could be the first method of choice for hydrocephalus even in children younger than 6 months of age.

Laser interstitial thermal therapy: A first line treatment for seizures due to hypothalamic hamartoma?

Successful treatment of hypothalamic hamartoma (HH) can result in the resolution of its sequelae including epilepsy and rage attacks. Risks and morbidity of open surgical management of this lesion have motivated the development of laser interstitial thermal therapy (LITT) as a less invasive treatment approach to the disease. Although overall morbidity and risk would appear to be lower, complications related to LITT therapy have been reported, and the longer-term follow-up that is now possible after initial experience helps address the question of whether LITT provides equivalent efficacy compared to other treatment options. We conducted a retrospective analysis of clinical outcomes in eight patients undergoing LITT for HH at our center using the Visualase/Medtronic device. Five patients had refractory epilepsy, one had rage attacks, and two had both. We also compared the published seizure-free outcomes over time and the complication rates for different interventional approaches to the treatment of epilepsy due to HH including open craniotomy, neuroendoscopic, radiosurgical, and radiofrequency approaches. With a mean follow-up of 19.1 months in our series of eight patients, six of seven epilepsy patients achieved seizure freedom, whereas the one patient with rage attacks only did not have improvement of his symptoms. A length of hospital stay of 2.6 days reflects low morbidity and rapid postoperative recuperation with LITT. Considering other reported series and case reports, the overall published seizure freedom rate of 21 of 25 patients is superior to published outcomes of HH cases treated by stereotactic radiosurgery (SRS), craniotomy, or neuroendoscopy, and comparable to radiofrequency ablation. The cumulative experience of our center with other published series supports relatively lower operative morbidity than more invasive approaches and efficacy that is as good or better than open craniotomy procedures and SRS. Although morbidity appears to be lower than other open approaches, complications related to LITT and their avoidance should be considered carefully.

Aquaporins in Brain Edema and Neuropathological Conditions.

The aquaporin (AQP) family of water channels are a group of small, membrane-spanning proteins that are vital for the rapid transport of water across the plasma membrane. These proteins are widely expressed, from tissues such as the renal epithelium and erythrocytes to the various cells of the central nervous system. This review will elucidate the basic structure and distribution of aquaporins and discuss the role of aquaporins in various neuropathologies. AQP1 and AQP4, the two primary aquaporin molecules of the central nervous system, regulate brain water and CSF movement and contribute to cytotoxic and vasogenic edema, where they control the size of the intracellular and extracellular fluid volumes, respectively. AQP4 expression is vital to the cellular migration and angiogenesis at the heart of tumor growth; AQP4 is central to dysfunctions in glutamate metabolism, synaptogenesis, and memory consolidation; and AQP1 and AQP4 adaptations have been seen in obstructive and non-obstructive hydrocephalus and may be therapeutic targets.

Hydrocephalus associated with childhood nonaccidental head trauma.

OBJECTIVE The incidence of posttraumatic ventriculomegaly (PTV) and shunt-dependent hydrocephalus after nonaccidental head trauma (NAHT) is unknown. In the present study, the authors assessed the timing of PTV development, the relationship between PTV and decompressive craniectomy (DC), and whether PTV necessitated placement of a permanent shunt. Also, NAHT/PTV cases were categorized into a temporal profile of delay in admission and evaluated for association with outcomes at discharge. METHODS The authors retrospectively reviewed the cases of patients diagnosed with NAHT throughout a 10-year period. Cases in which sequential CT scans had been obtained (n = 28) were evaluated for Evans' index to determine the earliest time ventricular dilation was observed. Discharge outcomes were assessed using the King's Outcome Scale for Childhood Head Injury score. RESULTS Thirty-nine percent (11 of 28) of the patients developed PTV. A low admission Glasgow Coma Scale (GCS) score predicted early PTV presentation (within < 3 days) versus a high GCS score (> 1 week). A majority of PTV/NAHT patients presented with a subdural hematoma (both convexity and interhemispheric) and ischemic stroke, but subarachnoid hemorrhage was significantly associated with PTV/NAHT (p = 0.011). Of 6 patients undergoing a DC for intractable intracranial pressure, 4 (67%) developed PTV (p = 0.0366). These patients tended to present with lower GCS scores and develop ventriculomegaly early. Only 2 patients developed hydrocephalus requiring shunt placement. CONCLUSIONS PTV presents early after NAHT, particularly after a DC has been performed. However, the authors found that only a few PTV/NAHT patients developed shunt-dependent hydrocephalus.

Hydrocephalus in children.

Imaging of hydrocephalus in utero, in infants and children is critically dependent on an understanding of the pathophysiology and treatment options for this condition in this age spectrum. For this reason, this chapter deals not only with the imaging modalities used to study hydrocephalus and how they are applied but also reviews key aspects of the pathophysiology and treatment of hydrocephalus in children. Imaging techniques to establish the diagnosis of chronic hydrocephalus fall into two categories: (1) tracer-type techniques that require an injection and observation of the transit of an injected substance through the ventricular system or subarachnoid space and (2) cross-sectional imaging, which allows for direct visualization of a point of obstruction within the ventricular system or subarachnoid space. For cross-sectional imaging, both magnetic resonance imaging (MRI) and computed tomography can be used, but MRI is usually preferred. Nomenclature has obscured the description of imaging findings in hydrocephalus. We suggest that most hydrocephalus is obstructive and propose to designate ventriculomegaly, the condition in which the ventricles are large on imaging, but there is no true obstruction to the outflow of cerebrospinal fluid.

Delay in Arrival to Care in Perpetrator-Identified Nonaccidental Head Trauma: Observations and Outcomes.

BACKGROUND: Children who sustained nonaccidental head trauma (NAHT) are at severe risk for mortality within the first 24 hours after presentation. OBJECTIVE: Extent of delay in seeking medical attention may be related to patient outcome. METHODS: A 10-year, single-institution, retrospective review of 48 cases treated at a large tertiary Children's Hospital reported to the New York State Central Registrar by the child protection team was conducted. The perpetrator was identified in 28 cases on the basis of confession or conviction. The medical and legal records allowed for identification of time of injury and the interval between injury and arrival to the hospital; this information was categorized as follows: <6 hours (without delay); 6-12 hours (moderate delay); and >12 hours (severe delay). The King's Outcome Scale for Childhood Head Injury (KOSCHI) score was recorded for each case. RESULTS: All children were 3 years of age or younger (2.1-34 months) and predominantly male (68%; 19/28). On arrival, 61% of patients (17/28) presented with moderate or severe delay. A low arrival Glasgow Coma Scale (GCS) score (P < 0.0001) and extracranial injuries (P < 0.0061) correlated with worse clinical patient outcomes. Patients with an arrival GCS score <7 predominantly arrived without delay or with moderate delay. Patients presenting without delay or with severe delay were more likely to have a higher KOSCHI outcome score on discharge (P < 0.0426). Four of the 6 patients who died presented after moderate delay. CONCLUSION: Patients presenting to medical care 6-12 hours after NAHT (moderate delay) appeared to have worse outcomes than those presenting earlier or later.

Lumboatrial shunt in a patient with Crouzon syndrome complicated by pseudotumor cerebri.

A 25-year-old man with Crouzon syndrome complicated by pseudotumor cerebri and multiple shunt failures presented with progressive back and neck pain, intermittent headaches, and associated vomiting secondary to shunt infection. Due to his previous history of repeated failure of both ventriculoperitoneal and lumboperitoneal (LP) shunting procedures, the decision was made to place a lumboatrial (LA) shunt via an approach through the internal jugular vein. The procedure was uncomplicated and the man's symptoms were relieved. Despite significant improvement, the LA shunt limited his exercise tolerance, and as an avid runner and weight lifter, he requested reconversion back to an LP shunt. At a follow-up of 20months, he continued to do well both clinically and radiographically. This case report summarizes the successful placement and use of an LA shunt for the treatment of intracranial hypertension in the setting of Crouzon syndrome.