[Spontaneous intracranial hypotension and Marfan syndrome]. / Spontanes Liquorunterdrucksyndrom und Marfan-Syndrom.

Spontaneous intracranial hypotension is the most common complication in patients undergoing a lumbar puncture. A much rarer entity is headaches attributed to spontaneous (or idiopathic) low cerebrospinal fluid (CSF) pressure but the combination with a connective tissue disorder is even rarer. The first case of a patient with spontaneous intracranial hypotension and genetically established Marfan syndrome was published in 1995. This article describes the cases of two female patients who presented with postural headache. Magnetic resonance imaging revealed multiple leakages of CSF and both patients had a genetically confirmed diagnosis of Marfan syndrome. The initial symptomatic treatment did not result in a significant relief of the headaches. Epidural blood patching was performed and the intervention was successful in both patients. Finally, the most important epidemiological, diagnostic and pathophysiological aspects are demonstrated and the therapeutic procedures are presented.

Systematic review of decreased intracranial pressure with optimal head elevation in postcraniotomy patients: a meta-analysis.

AIM: To determine an optimal head elevation degree to decrease intracranial pressure in postcraniotomy patients by meta-analysis. BACKGROUND: A change in head position can lead to a change in intracranial pressure; however, there are conflicting data regarding the optimal degree of elevation that decreases intracranial pressure in postcraniotomy patients. DESIGN: Quantitative systematic review with meta-analysis following Cochrane methods. DATA SOURCES: The data were collected during 2014; three databases (PubMed, Embase and China National Knowledge Internet) were searched for published and unpublished studies in English. The bibliographies of the articles were also reviewed. The inclusion criteria referred to different elevation degrees and effects on intracranial pressure in postcraniotomy patients. REVIEW METHODS: According to pre-determined inclusion criteria and exclusion criteria, two reviewers extracted the eligible studies using a standard data form. RESULTS: These included a total of 237 participants who were included in the meta-analysis. (1) Compared with 0 degree: 10, 15, 30 and 45 degrees of head elevation resulted in lower intracranial pressure. (2) Intracranial pressure at 30 degrees was not significantly different in comparison to 45 degrees and was lower than that at 10 and 15 degrees. CONCLUSION: Patients with increased intracranial pressure significantly benefitted from a head elevation of 10, 15, 30 and 45 degrees compared with 0 degrees. A head elevation of 30 or 45 degrees is optimal for decreasing intracranial pressure. Research about the relationship of position changes and the outcomes of patient primary diseases is absent.

Skull thickening, paranasal sinus expansion, and sella turcica shrinkage from chronic intracranial hypotension.

In children or young adults, the morphology of the skull can be altered by excessive drainage of CSF following placement of a ventriculoperitoneal (VP) shunt. In Sunken Eyes, Sagging Brain Syndrome, gradual enlargement of the orbital cavity occurs from low or negative intracranial pressure (ICP), leading to progressive bilateral enophthalmos. The authors report several heretofore unrecognized manifestations of this syndrome, which developed in a 29-year-old man with a history of VP shunt placement following a traumatic brain injury at the age of 9 years. Magnetic resonance imaging showed typical features of chronic intracranial hypotension, and lumbar puncture yielded an unrecordable subarachnoid opening pressure. The calvaria was twice its normal thickness, owing to contraction of the inner table. The paranasal sinuses were expanded, with aeration of the anterior clinoid processes, greater sphenoid wings, and temporal bones. The sella turcica showed a 50% reduction in cross-sectional area as compared with that in control subjects, resulting in partial extrusion of the pituitary gland. These new features broaden the spectrum of clinical findings associated with low ICP. Secondary installation of a valve to restore normal ICP is recommended to halt progression of these rare complications of VP shunt placement.

Shunt survival rates by using the adjustable differential pressure valve combined with a gravitational unit (proGAV) in pediatric neurosurgery.

OBJECT: Overdrainage is a chronic complication in shunted pediatric patients with hydrocephalus. The use of adjustability of differential pressure (DP) valves in combination with antisiphoning devices may help to overcome this sequela and may diminish the rate of possible shunt failures. The purpose of this retrospective study is to report our experience on shunt survival and infection rate with an adjustable DP valve with integrated gravitational unit in pediatric hydrocephalus. METHODS: The proGAV consists of an adjustable differential pressure (DP) valve and a gravitational unit. During the time period of July 2004 and December 2009, a total of 237 adjustable gravitational valves were used in 203 children (age, 6.5 ± 6.54; 0-27 years). In the follow-up period, valve and shunt failures as well as rate of infection were recorded. RESULTS: Within the average follow-up time of 21.9 ± 10.3 months (range, 6-72 months), the valve survival rate was 83.8 %. The overall shunt survival rate including all necessary revisions was 64.3 %. Looking at the group of infants (<1 year of age) within the cohort, the valve survival rate was 77.3 % and the shunt survival rate was 60.9 %. The overall infection rate was 4.6 %. CONCLUSION: In a concept of avoiding chronic overdrainage by using the proGAV in hydrocephalic children, we observed a good rate of valve and shunt survival. Compared to previous reported series, we experienced the proGAV as a reliable tool for the treatment of pediatric hydrocephalus.

Post-dural puncture headache: Part II--prevention, management, and prognosis.

Post-dural puncture headache (PDPH) is a frequent complication of lumbar puncture, performed for diagnostic or therapeutic purposes or accidentally, as a complication of epidural anesthesia. As PDPH can be disabling, clinicians who perform these procedures should be familiar with strategies for preventing this disorder. Since the best preventative measures sometimes fail, clinicians should also be familiar with the therapeutic approaches for PDPH. Herein, we review the procedure-related risk factors for PDPH, the prognosis of PDPH and the studies of PDPH treatment. We divide the therapeutic approach to PDPH into 4 stages: conservative management, aggressive medical management, conventional invasive treatments, and the very rarely employed less conventional invasive treatments and provide management algorithm to facilitate treatment.

Sitting position for removal of pineal region lesions: the Helsinki experience.

OBJECTIVE: To present a summary of anesthetic considerations for use of the sitting position in procedures to remove lesions of the occipital and suboccipital regions, with a special reference to the Helsinki experience with more than 300 operations in 1997-2007, and a retrospective study evaluating the incidence of venous air embolism (VAE) and hemodynamic stability in patients operated in the steep sitting position. METHODS: Anesthesiology reports of 72 patients with a mean (± standard deviation [SD]) age of 33 years ± 18 treated by the senior author (J.H.) for pineal region tumors using the infratentorial supracerebellar approach in the sitting position during an 11-year period were retrospectively reviewed for the incidence of VAE and hemodynamic stability. RESULTS: In the sitting position, median systolic blood pressure changed -8 (-95 to +50) mm Hg without alteration in heart rate. Based on patient records, the incidence of VAE was 19% (14 of 72 patients). In five patients, end-tidal carbon dioxide (ETCO(2)) decreased more than 0.7 kPa (5.25 mm Hg), possibly indicating VAE. Comparing patients with and without VAE, no differences in change of blood pressure, heart rate, or amount of administered vasoactive agents were observed. Postoperative duration of ventilator treatment and hospital stay were similar in patients with and without VAE. No signs of arterial embolization were seen postoperatively. CONCLUSIONS: The sitting position is associated with risk for hypotension. The same surgical approach and procedure does not exclude the occurrence of VAE. In this study, the unaltered hemodynamics in patients during VAE indicates relatively small VAE. Possible explanations for this are early recognition of air leakage and good cooperation between the surgical and anesthesia teams.

[Post-lumbar puncture syndrome and spontaneous low CSF pressure syndrome]. / Postpunktionelles und spontanes Liquorunterdrucksyndrom.

The major invasive procedure of the neurologist is the spinal tap. Its most frequent complication is post-lumbar puncture syndrome/headache. The syndrome's leading symptom is posture-dependent headache, which is caused by the prolonged escape of CSF from a dural leak. Its frequency lies between 1 and 30%, depending on the technique used for lumbar puncture. An important measure for reducing the risk of its occurrence is the use of a small (22-gauge), atraumatic Sprotte or Whitacre needle. The treatment of choice for the syndrome is caffeine, and if ineffective, then an epidural blood patch (at least 20 ml of the patient's own blood). Spontaneous low CSF pressure is due to a dural tear; it has the same symptoms as post-dural puncture headache, and on MRI there is a contrast enhancement of the meninges. In most cases the spontaneous low CSF pressure syndrome only is diagnosed after weeks to months. For this reason one should consider this syndrome in all cases of chronic headache. It is also treated with caffeine and an epidural blood patch. If it persists, the leak must be localized by means of radioisotope cisternography, thin-layer MRI, or CT myelography, and then the hole is closed either surgically or by CT-assisted application of fibrin glue.

Cylindrical channel retractor for intraventricular tumour surgery--a simple and inexpensive device.

Ventricular tumors are excised using both microscope and endoscope as the viewing device. Excision of these tumors requires corticectomy. After these corticectomies, brain has tendency to fall because of CSF drainage. Currently available retractor systems are fixed and thus can be traumatic. On the other hand few systems that require small corticectomy need stereotactic or navigation system aid. These all methods and equipment are costly. Our simple method of using a cylindrical channel retractor custom made out of 20 cc plastic syringe in OT helps in making minimum possible corticectomy. It gives surgeon minimally traumatic, inexpensive, hands free retractor.

Gravitational valves in supine patients with ventriculo-peritoneal shunts.

BACKGROUND: In the subgroup of bedridden hydrocephalic patients with ventriculo-peritoneal shunts and gravitational valves, we occasionally observed persisting hydrocephalic complaints even when mechanical or infection-related obstruction was excluded. METHODS: To investigate the cause of these hydrocephalic symptoms, in vitro and in vivo analyses were used to determine valve opening, intra-abdominal and hydrostatic pressure of an Aesculap-Miethke 10/40 cm H2O gravitational valve at different angles of upper body and head inclination. FINDINGS: Since hydrostatic pressure is lacking, the resulting intra-ventricular pressures are shown to peak up to 27 cm H2O in supine patients with head, but not upper body inclined. CONCLUSIONS: We conclude that in the subgroup of bedridden patients with ventriculo-peritoneal shunts and gravitational valves, upright posture is a prerequisite for proper cerebrospinal fluid drainage.

Severe traumatic brain injury: maximizing outcomes.

Severe traumatic brain injury is one of the leading causes of death and disability in the United States. The initial management of traumatic brain injury involves early resuscitation, computed tomography scanning, and surgical evacuation of mass lesions, when indicated. Recent research suggests that the prevention and treatment of secondary brain injury decrease mortality and improve outcomes. Specifically, treatment should address not only cerebral protection but also prevention of injury to other organ systems. To achieve the best outcomes, attention must be focused on optimizing blood pressure and brain tissue oxygenation, maintaining adequate cerebral perfusion pressures, and preventing seizures. In addition, maximizing good outcomes depends on proactively addressing the risk of common sequelae of brain injury, including infection, deep venous thrombosis, and inadequate nutrition. Guidelines developed for the management of severe traumatic brain injury have dramatically improved functional neurological outcomes.

Pediatric traumatic brain injury: quo vadis?

In this review, five questions serve as the framework to discuss the importance of age-related differences in the pathophysiology and therapy of traumatic brain injury (TBI). The following questions are included: (1) Is diffuse cerebral swelling an important feature of pediatric TBI and what is its etiology? (2) Is the developing brain more vulnerable than the adult brain to apoptotic neuronal death after TBI and, if so, what are the clinical implications? (3) If the developing brain has enhanced plasticity versus the adult brain, why are outcomes so poor in infants and young children with severe TBI? (4) What contributes to the poor outcomes in the special case of inflicted childhood neurotrauma and how do we limit it? (5) Should both therapeutic targets and treatments of pediatric TBI be unique? Strong support is presented for the existence of unique biochemical, molecular, cellular and physiological facets of TBI in infants and children versus adults. Unique therapeutic targets and enhanced therapeutic opportunities, both in the acute phase after injury and in rehabilitation and regeneration, are suggested.

Critical postcraniotomy cerebrospinal fluid hypovolemia: risk factors and outcome analysis.

OBJECTIVE: Critical cerebrospinal fluid (CSF) hypovolemia may cause acute postoperative clinical deterioration in aneurysmal subarachnoid hemorrhage patients after craniotomy for microsurgical aneurysm clipping. We sought to identify risk factors for critical CSF hypovolemia and determine this syndrome's effect on clinical outcome. METHODS: Between April 2001 and June 2004 at Columbia University Medical Center, 16 aneurysmal subarachnoid hemorrhage patients were diagnosed with postoperative critical CSF hypovolemia, whereas 151 patients who underwent craniotomy for clipping were not. The demographics, as well as the presenting radiographic and clinical characteristics, of these groups were evaluated. In addition, a 2:1 matched case-control comparison of patients with and without critical CSF hypovolemia was completed using clinical data, operative variables, and outcome data. Outcome analysis was performed with a battery of tests designed to assess global outcome, cognitive function, independence, and quality of life. RESULTS: There was no difference in clinical grade, Fisher score, age, and sex distribution between patients diagnosed with critical CSF hypovolemia and the general aneurysmal subarachnoid hemorrhage population at Columbia University Medical Center. Subsequent 2:1 matched case-control comparison demonstrated a higher incidence of global cerebral edema on admission computed tomographic scans (75 versus 31%; P < 0.01) and a significantly longer operative time for patients with critical CSF hypovolemia (5 h 18 min versus 4 h 22 min; P < 0.03). No significant differences were observed between groups in outcome assessments at the time of hospital discharge or the 3-month follow-up examination. CONCLUSION: Risk factors associated with an increased incidence of critical CSF hypovolemia after aneurysm surgery include the presence of global cerebral edema on admission head computed tomographic scans and prolonged operative time. In such patients, heightened suspicion of CSF hypovolemia is crucial because rapid and appropriate management obviates excess morbidity and mortality.

Cerebral circulation monitoring in carotid endarterectomy and carotid artery stenting.

In the near future it is likely that surgeons, anesthesiologists, and interventional radiologists and cardiologists will care for increasing numbers of patients undergoing carotid endarterectomy (CEA) and carotid angioplasty and stenting (CAS). Perhaps the most important factor in assuring technically acceptable interventions is the availability of an experienced team with demonstrable low periprocedural morbidity and mortality and a proper understanding of both vascular principles and cerebral physiology. Although different monitoring techniques have proven successful during both surgical and endovascular carotid interventions, the advantages of periprocedural transcranial Doppler (TCD) monitoring, such as its sensitivity for recording blood flow velocities and microembolism in real-time, are convincing. Because of its high temporal resolution, it provides additional information about the cerebral circulation, especially during cross-clamping, clamp release, and balloon inflation and deflation, respectively. If made audible during the procedure, it also provides unique information concerning cerebral micro-embolization. In CEA, TCD monitoring gives a better understanding of the pathophysiology of complications and makes the operation safer. In CAS, it gives insight into the clinical relevance of cerebral embolism and the possible effects of protection devices.

The use of an adjustable valve to treat over-drainage of a cyst-peritoneal shunt in a child with a large sylvian fissure arachnoid cyst.

INTRODUCTION: The cyst-peritoneal shunt is a recognised surgical alternative in the management of sylvian fissure arachnoid cysts. Shunt overdrainage is well described in literature on ventriculo-peritoneal shunts, but not often appreciated as a complication of cysto-peritoneal shunts. CASE REPORT: A 5-year-old boy presented with a symptomatic left sylvian fissure arachnoid cyst. This was initially treated by craniotomy and membrane fenestration in the carotid cistern. Recurrence led to insertion of a valveless cyst-peritoneal shunt 5 months later. Initial progress was followed by persistent headaches 18 months after shunt insertion. CT scan revealed a significant reduction in the cyst size, enlargement of the ipsilateral lateral ventricle, collapse of the contra-lateral ventricle and midline shift towards the side of the shunt. These findings were interpreted as over-drainage of the cyst-peritoneal shunt. RESULT: A Codman Medos adjustable valve was inserted, with the intention of gradually increasing the pressure until the midline shift was restored and the contra-lateral ventricle was reconstituted. This was achieved with the valve set at 90 mm H(2)O, verified by CT scan. Radiological improvement was associated with dramatic symptomatic improvement. CONCLUSION: Over-drainage of cyst-peritoneal shunts is often not appreciated, especially when the main manifestation is headaches. As it is difficult to predict the required valve pressure setting, it may be advisable to consider the use of an adjustable valve.

[Methods of reducing the number of complications and relapses after microvascular decompression in patients with trigeminal neuralgia]. / Puti umen'sheniia oslozhnenii i retsidivov posle mikrovaskuliarnoi dekompressii u bol'nykh s trigeminal'noi nevralgiei.

Techniques and methods of preventing the disease relapses and possible postoperative complications, e.g. vestibuloatactic syndrome, impairment or loss of hearing, paresis of the mimic muscles, syndrome of intracranial hypotension etc., are suggested on the basis of an analysis of results of 94 microvascular decompression operations of the trigeminal nerve root implemented in patients with trigeminal neuralgia. A contact with venous vessel is not a reason, according to the authors, of trigeminal neuralgia. The authors point out the need in a thorough revision of all surfaces of the trigeminal nerve root (but not only of its portal zone) for the purpose of detecting and removing all possible conflict points, which significantly reduces the number of possible disease relapses. The preservation of the petrosal vein and of its tributaries and, primarily, of the lateral inversion vein of ventricle IV is an important factor in preventing the postoperative vestibular-and-cerebellar disorders. The controllable exfusion of liquor, before opening up the dura matter of the brain, facilitates the approach to the neurovascular-conflict location by avoiding tension of the roots of cranial-and-cerebral nerves. The autoliquortransfusion, made at final operation stage, ensures the recovery of the intracranial pressure to normal values, thus, preventing a possible hypotensive syndrome and hydrops labyrinthine, which can lead to an impaired hearing and vestibuloatactic syndrome.

What is the optimal cerebral perfusion pressure in children suffering from traumatic coma?

Head injury is a major cause of death and disability in children. Despite advances in resuscitation, emergency care, intensive care monitoring, and clinical practices, there are few data demonstrating the predictive value of certain physiological variables regarding outcome in this patient population. Mean arterial blood pressure (MABP), intracranial pressure (ICP), and cerebral perfusion pressure (CPP = MABP - ICP) are routinely monitored in patients in many neurological intensive care units throughout the world, but there is little evidence indicating that advances in care have been matched with corresponding improvements in outcome. Nonetheless, there is evidence that hypotension immediately following head injury is predictive of early death, and many patients with these features die with clinical signs of brain herniation caused by intracranial hypertension. Furthermore, available data indicate that a minimal and a mean CPP measured during intensive care are good predictors of outcome in survivors, but a target threshold to improve outcome has yet to be defined. Some medical management strategies can have detrimental effects, and there is now a good case for undertaking a controlled trial of immediate or delayed craniectomy. Independent outcome in children following severe head injury is associated with higher levels of CPP. The ability to tolerate different levels of CPP may be related to age, and therefore any such surgical trial would need a carefully defined protocol so that the potential benefit of such a treatment is maximized.

What is the optimal threshold for cerebral perfusion pressure following traumatic brain injury?

Intensive care of the patient with traumatic brain injury centers on control of intracranial pressure and cerebral perfusion pressure (CPP). The optimal CPP by definition delivers an adequate supply of blood and oxygen to meet the metabolic demands of brain tissue. A great deal of controversy exists regarding the optimal CPP value, with disparate studies providing conflicting evidence for the use of supraphysiological CPP values. No study that accurately assesses the efficacy of normal CPP compared with elevated CPP has been performed, but several studies demonstrate that a CPP threshold exists on an individual basis for patients with TBI. The use of brain monitors of cerebral metabolism and oxygen supply may assist the clinician in the selection of the optimal CPP for an individual patient.

Assessment of critical thresholds for cerebral perfusion pressure by performing bedside monitoring of cerebral energy metabolism.

An intractable increase in intracranial pressure (ICP) leading to a progressive decrease in cerebral perfusion pressure (CPP) and cerebral blood flow (CBF) is the dominating cause of death in patients with severe brain trauma. Arterial hypotension may further compromise CPP (and CBF) and significantly contributes to death. In addition, the injured brain is sensitive to raised CPP due to an increased permeability of the blood-brain barrier (BBB) to crystalloids and an impaired pressure autoregulation of the CBF. Given these circumstances, an increase in CPP will cause a net transport of water across the BBB and a further elevation in ICP. Accordingly, the assessment of the lower critical threshold for CPP is important for neurological intensive care. This level varies among different patients and different areas of the brain. In fact, the penumbral zones surrounding focal brain lesions appear to be the most sensitive. In the individual patient, preservation of normal cerebral energy metabolism within areas at risk during a decrease in CPP can be guaranteed by performing intracerebral microdialysis and bedside biochemical analyses.