Neuromodulation and deep brain stimulation (DBS) have been increasingly used in many neurological ailments, including essential tremor, Parkinson’s disease, epilepsy, and more. Yet for many patients and practitioners the desire to utilize these therapies is met with caution, given the need for craniotomy, lead insertion through brain parenchyma, and, at many times, bilateral invasive procedures. Currently endovascular therapy is a standard of care for emergency thrombectomy, aneurysm treatment, and other vascular malformation/occlusive disease of the cerebrum. Endovascular techniques and delivery catheters have advanced greatly in both their ability to safely reach remote brain locations and deliver devices. In this review the authors discuss minimally invasive endovascular delivery of devices and neural stimulating and recording from cortical and DBS targets via the neurovascular network.

Ethylene glycol is found in many household products and is a common toxic ingestion. Acute ingestions present with altered sensorium and an osmolal gap. The true toxicity of ethylene glycol is mediated by its metabolites, which are responsible for the increased anion gap metabolic acidosis, renal tubular damage, and crystalluria seen later in ingestions. Early intervention is key; however, diagnosis is often delayed, especially in elderly patients presenting with altered mental status. There are several laboratory tests which can be exploited for the diagnosis, quantification of ingestion, and monitoring of treatment, including the lactate and osmolal gaps. As methods of direct measurement of ethylene glycol are often not readily available, it is important to have a high degree of suspicion based on these indirect laboratory findings. Mainstay of treatment is bicarbonate, fomepizole or ethanol, and, often, hemodialysis. A validated equation can be used to estimate necessary duration of hemodialysis, and even if direct measurements of ethylene glycol are not available, monitoring for the closure of the anion, lactate, and osmolal gaps can guide treatment. We present the case of an elderly male with altered mental status, acute kidney injury, elevated anion gap metabolic acidosis, and profound lactate and osmolal gaps.

OBJECTIVELumboperitoneal (LP) shunts have a role not only in pseudotumor cerebri, but also in patients with slit-like ventricles who are treated with CSF shunting on a chronic basis. Hesitation to utilize LP shunts is based on previous conventional beliefs including the tendency for overdrainage, difficulties accessing the shunt to tap or revise, and risk of progressive cerebellar tonsillar herniation. The authors hypothesized that the use of horizontal-vertical (HV) valves may reduce the risk of these complications, particularly overdrainage and development of Chiari malformation.METHODSAll pediatric cases involving patients treated with an LP shunt at the Children’s Hospital of Michigan were reviewed in this retrospective case series. A total of 143 patients with hydrocephalus were treated with LP shunts from 1997–2015 (follow-up range 8 months–8 years, median 4.2 years). Patients with pseudotumor cerebri underwent placement of an LP shunt as a primary procedure. In patients with slit ventricles from chronically treated hydrocephalus or repeated shunt malfunctions from proximal catheter obstruction, a lumbar drain was inserted to assess candidacy for conversion to an LP shunt. In patients who tolerated the lumbar drain and demonstrated communication of the ventricles with the spinal cisterns, treatment was converted to an LP shunt. All patients included in the series had undergone initial shunt placement between birth and age 16 years.RESULTSIn 30% of patients (n = 43), LP shunts were placed as the initial shunt treatment; in 70% (n = 100), treatment was converted to LP shunts from ventriculoperitoneal (VP) shunts. The patients’ age at insertion of or conversion to an LP shunt ranged from 1 to 43 years (median 8.5 years). Of the patients with clear pre-LP and post-LP shunt follow-up imaging, none were found to develop an acquired Chiari malformation. In patients with pre-existing tonsillar ectopia, no progression was noted on follow-up MRIs of the brain in these patients after LP shunt insertion. In our LP shunt case series, no patient presented with acute deterioration from shunt malfunction.CONCLUSIONSConversion to an LP shunt may minimize acute deterioration from shunt malfunction and decrease morbidity of repeated procedures in patients with chronically shunt-treated hydrocephalus and small ventricles. In comparison to previously published case series of LP shunt treatment, the use of LP shunts in conjunction with HV valves may decrease the overall risk of cerebellar tonsillar herniation. The use of an LP shunt may be an alternative in the management of slit ventricles when VP shunting repeatedly fails.