Cerebrovascular physiology in perinates with congenital hydrocephalus.

PURPOSE: This study investigated changes in regional cerebral blood flow (rCBF), autoregulation (AR), and mean CO(2) reactivity (CO(2)r) in nine neonates, who underwent cerebrospinal fluid (CSF) diversion for congenital hydrocephalus. METHODS: During shunt insertion, a thermal diffusion probe inserted adjacent to the ventricular catheter in the right parietal region recorded rCBF. Changes in rCBF, mean arterial pressure, intracranial pressure (ICP), and expired CO(2) tension were recorded before and after removing CSF. RESULTS: Mean baseline rCBF for the entire group was 19.5 mL/100 g/min (range 8.4-44.8), with a mean ICP of 9.9 mmHg (range 4-20). Following CSF removal, the rCBF increased significantly in two patients. Three patients demonstrated AR throughout their studies; one infant showed AR after CSF removal. One infant without AR during shunt insertion showed an increase in rCBF and AR during a revision 5 months later. Baseline CO(2)r varied considerably but was greater than two in two patients and increased in three other children after CSF removal. Mean follow-up was 23.6 months. One child, with severe developmental delay, died. Death or severe delay was associated with the absence of AR and a negative CO(2)r in three children. Normal or mild developmental delay was associated with AR and a neutral or positive CO(2)r in five patients. CONCLUSIONS: Baseline levels of rCBF were not associated with developmental prognosis. AR and a positive CO(2)r were necessary but insufficient factors for normal development. The absence of AR and a negative CO(2)r were associated with poor prognosis.

Cauda equina syndrome (CES) from lumbar disc herniations.

STUDY DESIGN: A retrospective review was performed to determine the outcomes of patients with cauda equina syndrome (CES) from a herniated lumbar disc at our institutions. OBJECTIVE: CES from lumbar herniated discs is considered the only absolute indication for surgery. It is considered a neurosurgical emergency with the outcome related to how quickly it is diagnosed and treated. The results of recovery of bladder function are felt by many authors to be related to early diagnosis and surgical intervention. Most authors recommend a wide decompressive laminectomy when surgery is performed. We reviewed our cases to determine if they conformed to these assumptions. SUMMARY OF BACKGROUND DATA: Although many articles regarding the outcome of CES from herniated lumbar discs suggest that early surgery is superior to surgery that is delayed, others have demonstrated no correlation between time-to-surgery and chances for recovery of neurologic and bladder function. METHODS: A retrospective review of all patients with lumbar herniated discs and CES from the years 1985 to 2004 was carried out. There were 31 patients, 28 of whom had bladder incontinence or retention requiring catheterization. Six patients were operated within 24 hours, 8 between 24 and 48 hours, and 17 after 48 hours (range: 60 h to 2 wk). Average follow-up was 5 years. RESULTS: Twenty-seven of these patients regained continence not requiring catheterization. There was no correlation between the time-to-surgery and recovery of bladder function. There was also no correlation between the time-to-surgery and recovery of motor and sensory function. The majority of patients underwent unilateral hemilaminotomy or bilateral hemilaminotomies; decompressive laminectomy was reserved for patients with underlying spinal stenosis or posteriorly herniated fragments. All of the patients were relieved of their radicular pain. CONCLUSIONS: In our series of patients with CES and bladder incontinence or retention, over 90% regained continence. Recovery of function was not related to the time to surgical intervention. The majority of the patients were adequately treated without the need for a complete laminectomy.

Tumefaction of the dural sinuses associated with a coagulopathy following treatment of hydrocephalus in a perinate: case report.

The authors describe an infant with abnormal development of the cerebral venous system associated with in utero ventriculomegaly and perinatal hemorrhage. When the patient was 6 weeks of age progressive ventriculomegaly followed by cerebrospinal fluid diversion resulted in tumefaction of the dural sinuses, intravascular thrombosis, and a coagulopathy. Oral anticoagulation therapy safely reversed the coagulopathy. Serial neuroimaging findings in this unique cascade of pathophysiological events indicated that, despite decreased intracranial pressure after shunt placement, local hemodynamic factors increased the venous resistance to flow and prolonged the transit time. Long-term anticoagulation therapy was associated with improvements in flow, transit time, and tumefaction.

Surgery of the head and 70-day brain surgeons.

In 1917, the Sugeon General of the United States Army, William Gorgas, learned that almost 15% of the casualties on the Western Front sustained intracranial injuries. Soon after the United States declared war in April 1917, the Council of National Defense established a General Medical Board and attached a brain surgery subsection to its Committee of Ophthalmology. Postcards were sent to experts around the country, asking for the names of individuals who had specialty training or practice in brain surgery. In August, Gorgas assumed control of this subsection and created a Division of Surgery of the Head in the American Army Medical Department, with additional sections for plastic surgery, ophthalmology, and otolaryngology. He needed almost 300 brain surgeons; he received 50 names. As Harvey Cushing, Gilbert Horrax, and others went to France, neurosurgeons at home trained student officers. Schools were established in Philadelphia (Charles Frazier), Chicago (Dean Lewis), New York City (Charles Elsberg), St. Louis (Ernest Sachs), and Camp Greenleaf in Georgia (Claude Coleman), with 10-week intensive courses for selected candidates. Basic science and x-ray classes and operative clinics addressed most aspects of neurosurgical care. An army manual outlined clinical diagnoses and surgical techniques. Lewis H. Weed established a laboratory at Johns Hopkins Hospital, staffed by volunteers such as K.D. Blackfan and W.E. Dandy, to investigate infections of the central nervous system. By the time of the armistice, Gorgas had his complement of brain surgeons. The newly trained brain surgeons and their mentors gradually made their way to the Western Front during the summer of 1918. Plans for a neurosurgical school in France were quickly discarded as the American Army Medical Department changed the specialized assignments to front-line general surgical care. Some of the 190 brain surgeons in the American Expeditionary Forces, notably Gilbert Horrax, Charles E. Dowman, and Charles Neuhoff, treated head injuries exclusively, whereas others, such as Eustace Semmes and Howard Naffziger, treated all battle casualties depending on the tactical circumstances. The rational but naive recommendations for coordinated care made by Cushing, as senior consultant in neurosurgery, were hindered by the confusion of the St. Mihiel and Meuse-Argonne offensives and the chaos of war. Only three 70-day brain surgeons participated in the postwar development of the specialty. However, 9 of 10 original members of the Neurosurgical Club, which was established 18 months after the armistice, taught in American Army Medical Department courses or served on the Western Front. The schools and their teachers emphasized a growing recognition of neurosurgical expertise in the early 20th century.

Headaches, shunts, and obstructive sleep apnea: report of two cases.

OBJECTIVE: This report describes two shunted patients evaluated with continuous intracranial pressure (ICP) monitors for worsening headaches and subsequently diagnosed with obstructive sleep apnea. CLINICAL PRESENTATION AND INTERVENTION: ICPs were monitored with strain-gauge sensors inserted into the frontal cortex. After the initial diagnosis of sleep apnea, 8-hour attended polysomnography was performed in each patient. Both patients showed apnea-hypopnea indices greater than 15. Consequently, a "split-night study" was performed to evaluate treatment with titrated nasal continuous positive airway pressure. Patient 1 was a 42-year-old woman (body mass index, 34.1) with a 16-year history of idiopathic intracranial hypertension treated with lumboperitoneal and ventriculoperitoneal shunts. Patient 2 was a 20-year-old man (body mass index, 64.4) with the Arnold-Chiari II malformation. The patient had had a low-pressure shunt since birth. Neurological examinations were normal or unchanged before evaluation. Neurophthalmological examinations were normal. Computed tomographic scans failed to show progressive ventriculomegaly. Awake ICPs were less than 15 mm Hg. Nighttime ICPs during rapid eye movement sleep showed multiple Lundberg A waves associated with obstructive sleep apnea and hypoxemia. Blood pressure did not change during these episodes. Polysomnography showed apnea-hypopnea indices of 31 and 41, respectively. Continuous positive airway pressure reduced apnea-hypopnea indices to 17 and 0, respectively; headaches resolved with outpatient therapy. CONCLUSION: These observations suggest adequate shunting with reduced cerebral compliance in both patients. Altered respiratory mechanics associated with hypoxemia may have triggered cerebral vasodilation and increases in cerebral blood volume, particularly during rapid eye movement sleep. In noncompliant systems, these changes precipitated sustained elevations in ICP and intermittent headaches relieved by continuous positive airway pressure. The clinical patterns also suggest that obstructive sleep apnea should be considered in shunted patients with isolated symptoms of increasing headaches.

The use of recombinant activated factor VII to reverse warfarin-induced anticoagulation in patients with hemorrhages in the central nervous system: preliminary findings.

OBJECT: In this report the authors describe the use of the hemostatic agent recombinant activated factor VII (rFVIIa) in the perioperative treatment of hemorrhages in the central nervous system that are associated with warfarin therapy. METHODS: Two patients sustained hemorrhages within the spinal canal, and the other two had acute intracranial subdural hematomas. All patients had normal platelet counts, activated partial thromboplastin times, and fibrinogen levels, and all received fresh frozen plasma in conjunction with rFVIIa. The initial international normalized ratios (INRs) ranged from 1.9 to 5.6. Each dose of rFVIIa was 1200 microg, ranging from 16 to 22 microg/kg of body weight. Two patients received two perioperative doses of rFVIIa; the others required just one dose before surgery. The INR normalized within 2 hours of administration of rFVIIa in all patients. There were no thromboembolic complications, and surgical blood loss was less than 100 ml for all operations. CONCLUSIONS: This clinical experience indicates that rFVIIa may be safe and effective as the initial hemostatic agent for rapid reversal of orally administered anticoagulation medications in patients who require urgent neurosurgical intervention.

Nelson's wound: treatment of spinal cord injury in 19th and early 20th century military conflicts.

During the first half of the 19th century, warfare did not provide a background for a systematic analysis of spinal cord injury (SCI). Medical officers participating in the Peninsular and Crimean Wars emphasized the dismal prognosis of this injury, although authors of sketchy civil reports persuaded a few surgeons to operate on closed fractures. The American Medical and Surgical History of the War of the Rebellion was the first text to provide summary of results in 642 cases of gunshot wounds of the spine. The low incidence of this injury (0.26%) and the high mortality rate (55%) discouraged the use of surgery in these cases. Improvements in diagnoses and the introduction of x-ray studies in the latter half of the century enabled Sir G. H. Makins, during the Boer War, to recommend delayed intervention to remove bone or bullet fragments in incomplete injuries. The civil experiences of Elsberg and Frazier in the early 20th century promoted a meticulous approach to treatments, whereas efficient transport of injured soldiers during World War I increased the numbers of survivors. Open large wounds or cerebrospinal fluid leakage, signs of cord compression in recovering patients, delayed clinical deterioration, or intractable pain required surgical exploration. Wartime recommendations for urological and skin care prevented sepsis, and burgeoning pension systems provided specialized longterm rehabilitation. By the Armistice, the effective surgical treatment and postoperative care that had developed through decades of interaction between civil and military medicine helped reduce incidences of morbidity and dispel the hopelessness surrounding the combatant with an SCI.

Asymptomatic aneurysm of the cavernous and supraclinoid internal carotid artery in a patient with Balamuthia mandrillaris encephalitis.

This is the first report to our knowledge of the successful treatment of an asymptomatic mycotic aneurysm associated with Balamuthia mandrillaris encephalitis. A 27-year-old male with end-stage renal disease presented with generalized seizures following renal transplantation. MRI demonstrated multiple brain masses and an aneurysm of the cavernous and supraclinoid carotid artery. Autopsy of the donor's brain revealed Balamuthia encephalitis. The patient was placed on an anti-amebic regimen, his condition improved, and 126 days after the kidney transplant, MRI brain showed resolution of the aneurysm and improvement of the enhancing lesions. Balamuthia mandrillaris has been shown to cause a granulomatous encephalitis, with prominent vasculitis. This is the first report to demonstrate the risk of aneurysm formation associated with this infection. Prolonged anti-amebic treatment resulted in resolution of the aneurysm without clinical evidence of subarachnoid hemorrhage.

Intracranial hemorrhage following blunt injury to a shunt valve.

CASE REPORT: The authors report a case of a child who sustained blunt injury to a shunt valve during a basketball game, which resulted in an intracranial hemorrhage. CONCLUSION: This occurrence, although rare, reinforces the recommendation for protective headgear when patients with shunts engage in activities that may result in direct impact to the head.

Changes in visual acuity associated with shunt failure.

OBJECT: The object of this article was to report on a retrospective analysis of the clinical findings in a series of patients with changes in visual acuity associated with shunt failure. METHODS AND RESULTS: Over a 10-year period, 350 patients underwent revisions for shunt failure. The clinical course of patients who demonstrated changes in visual acuity (VA) before or during hospitalization were reviewed; follow-up was achieved using outpatient records and telephone calls with physicians, family, or caregivers. Six patients (4 male) ranging in age from 2.5 years to 40 years demonstrated changes in vision associated with shunt failure. The youngest patient lapsed into coma before transfer and showed bilateral occipital lobe infarctions on the CT scan. Three patients had no complaints referable to the visual system prior to revision. Two patients with symptoms lasting more than 21 days showed unequivocal signs of increased intracranial pressure. Serial CT scans remained unchanged in 2 patients. A 3rd patient showed questionable progression in ventricular volume, while another patient's ventricles dilated after a period of 48-72 h. Four patients demonstrated a pattern of aqueductal stenosis, long-term shunting without revision, small ventricles, and poor outpatient follow-up. Four patients showed partial or complete recovery following revision. CONCLUSIONS: Changes in vision are uncommon and can be an isolated finding associated with shunt failure. Patients with aqueductal stenosis, long-term shunting without revision, and small, potentially non-compliant ventricles may be at risk of this complication. Misdiagnosis or inadequate follow-up places these patients at additional risk, but rapid revision can result in partial or complete recovery.