Ian K. Pople

The role of endoscopic biopsy and third ventriculostomy in the management of pineal region tumours

The best surgical strategy for treating patients with pineal tumours presenting with acute hydrocephalus remains undermined. During the past 17 years we have used transventricular endoscopic biopsy and third ventriculostomy as a one-step procedure in the initial management of these cases, and present the largest consecutive case series illustrating the value of this technique. We have successfully managed 34 consecutive patients with pineal region tumours, carrying out third ventriculostomy in 18 patients. Histological diagnosis was obtained in 32/34 (94%) of the cases. There were no deaths or major complications and only one patient required a ventriculo-peritoneal shunt owing to ventriculostomy failure. According to current management protocols and depending on histology, tumours were treated by a combination of resection via craniotomy followed by radiotherapy or chemotherapy, or by the latter therapies alone. This one step procedure is minimally invasive and safely achieves adequate biopsy with control of hydrocephalus, whilst definitive histology and biochemical marker studies are obtained. Definitive treatment for each tumour is designed according to diagnosis.The best surgical strategy for treating patients with pineal tumours presenting with acute hydrocephalus remains undermined. During the past 17 years we have used transventricular endoscopic biopsy and third ventriculostomy as a onestep procedure in the initial management of these cases, and present the largest consecutive case series illustrating the value of this technique. We have successfully managed 34 consecutive patients with pineal region tumours, carrying out third ventriculostomy in 18 patients. Histological diagnosis was obtained in 32/34 (94%) of the cases. There were no deaths or major complications and only one patient required a ventriculo-peritoneal shunt owing to ventriculostomy failure. According to current management protocols and depending on histology, tumours were treated by a combination of resection via craniotomy followed by radiotherapy or chemotherapy, or by the latter therapies alone. This one step procedure is minimally invasive and safely achieves adequate biopsy with control of hydrocephalus, whilst definitive histology and biochemical marker studies are obtained. Definitive treatment for each tumour is designed according to diagnosis.

Conservative management of patients with cerebrospinal fluid shunt infections.

OBJECTIVE:In patients with cerebrospinal fluid (CSF) shunt infection, removal of the shunt and antibiotic administration is the current standard of care. In 1986, we developed a protocol for the conservative management of patients with infected but functioning shunts. Treatment was based on the administration of a combination of intraventricular and systemic antibiotics. Intraventricular antibiotics were instilled via a separate access device. The purpose of this report is to describe our experience with this therapeutic intervention. METHODS:An observational study of all patients treated for CSF shunt infection between 1986 and 2003 was undertaken. Cure was defined by sterile CSF after completion of therapy and sterile shunt components at next revision or long-term freedom from recurrent infection (follow-up period, 6–88 mo). RESULTS:In total, 43 of 122 patients with CSF shunt infections were treated conservatively according to our protocol. Overall, 84% of these patients were cured, with a 92% success rate for patients with infections caused by bacteria other than Staphylococcus aureus. This included 30 coagulase-negative staphylococcal infections, of which two were treatment failures. We abandoned conservative treatment of patients with Staphylococcus aureus infections after early experience demonstrated that the success rate (four treatment failures in seven patients) was markedly lower than that for other pathogens. During the treatment and follow-up periods, there were three deaths, two of which were unrelated to shunt infection; treatment failure could not be completely excluded in the remaining patient. There was no toxicity related to intraventricular antibiotic administration. The incidence of shunt blockage among patients who were treated conservatively was not significantly different from that among a large cohort of patients with uninfected shunts. Ten patients received part of their courses of treatment as outpatients. CONCLUSION:The success rate of conservative management of patients with CSF shunt infections caused by coagulase-negative staphylococci is comparable with those in the published literature for patients treated conventionally. This form of management avoids surgical intervention, with its attendant risks, and is safe.

Randomized Clinical Trial of Prevention of Hydrocephalus After Intraventricular Hemorrhage in Preterm Infants: Brain-Washing Versus Tapping Fluid

OBJECTIVE. Hydrocephalus is a serious complication of intraventricular hemorrhage in preterm infants, with adverse consequences from permanent ventriculoperitoneal shunt dependence. The development of hydrocephalus takes several weeks, but no clinical intervention has been shown to reduce shunt surgery in such infants. The aim of this study was to test a new treatment intended to prevent hydrocephalus and shunt dependence after intraventricular hemorrhage. METHODS. We randomly assigned 70 preterm infants who had gestational ages of 24 to 34 weeks and were progressively enlarging their cerebral ventricles after intraventricular hemorrhage to either (1) drainage, irrigation, and fibrinolytic therapy to wash out blood and cytokines or (2) tapping of cerebrospinal fluid by reservoir as required to control excessive expansion and signs of pressure (standard treatment). We evaluated outcomes at 6 months of age or hospital discharge (if later). RESULTS. Of 34 infants who were assigned to drainage, irrigation, and fibrinolytic therapy, 2 died and 13 underwent shunt surgery (dead or shunt: 44%). Of 36 infants who were assigned to standard therapy, 5 died and 14 underwent shunt surgery (dead or shunt: 50%). This difference was not significant. Twelve (35%) of 34 infants who received drainage, irrigation, and fibrinolytic therapy had secondary intraventricular hemorrhage compared with 3 (8%) of 36 in the standard group. Secondary intraventricular hemorrhage was associated with an increased risk for subsequent shunt surgery and more blood transfusions. CONCLUSIONS. Despite its logical basis and encouraging pilot data, drainage, irrigation, and fibrinolytic therapy did not reduce shunt surgery or death when tested in a multicenter, randomized trial. Secondary intraventricular hemorrhage is a major factor that counteracts any possible therapeutic effect from washing out old blood.

Transforming Growth Factor-β1: A Possible Signal Molecule for Posthemorrhagic Hydrocephalus?

Posthemorrhagic hydrocephalus remains a complication of preterm birth for which we lack a clear understanding and a curative therapy. Transforming growth factor β (TGF-β) is a cytokine that upregulates the production by fibroblasts of extracellular matrix proteins. We hypothesized that TGF-β might be released into cerebrospinal fluid (CSF) after intraventricular hemorrhage and play a role in posthemorrhagic hydrocephalus. Total TGF-β1 and TGF-β2 were measured by immunoassay in CSF samples from 12 normal preterm infants, nine preterm infants with transient posthemorrhagic ventricular dilation, and 10 infants who subsequently developed permanent hydrocephalus. Five infants received intraventricular tissue plasminogen activator, and two infants were treated by drainage irrigation and fibrinolytic therapy. Median TGF-β1 in normal CSF was 0.495 ng/mL. In infants with transient posthemorrhagic ventricular dilation, median initial CSF TGF-β1 was 2.1 ng/mL. Infants who subsequently had permanent hydrocephalus had median initial CSF TGF-β1, 9.7 ng/mL (differences between groups p< 0.01). Intraventricular recombinant tissue plasminogen activator was followed by a rise in CSF TGF-β1 (p = 0.0007). Drainage irrigation and fibrinolytic therapy was followed by a fall in CSF TGF-β1. TGF-β2 was detected in CSF and showed similar trends, but the CSF concentration of TGF-β1 was more than 20 times higher. These findings support the hypothesis that TGF-β1 is released into CSF after intraventricular hemorrhage and may play an important part in hydrocephalus. The results help to explain the failure of intraventricular fibrinolytic therapy.

Spine update: prevention of postoperative infection in patients undergoing spinal surgery.

In a climate of clinical governance and evidence-based medicine, medical audit and other procedures are being used increasingly to evaluate clinical experience and as a basis for guidelines and recommendations on best clinical practice. In some areas of surgery and medicine, however, a structured approach is not possible because the data on which the assessments depend simply do not exist or are not sufficiently robust. This is the situation that applies to the use of systemic antibiotics for the prevention of infection following both spinal surgery and diagnostic and therapeutic procedures involving violation of one or more disc spaces, to the irrigation of spinal wounds with antibiotic or antiseptic solutions and to the use of drains in spinal surgery. In such circumstances, any attempt to provide guidance on the rational use of antibiotics must be based on a critical review of the relevant literature, experience in the management of neurosurgical/orthopedic infections, and a thorough knowledge of the antimicrobials currently available. Antibiotics are used widely, perhaps even routinely, to prevent postoperative infection in patients undergoing spinal surgery, but the evidence to support the efficacy of this intervention is not robust. For the purposes of this review, the role of antibiotic prophylaxis in spinal surgery will be considered under two headings: the prevention of surgical site (wound) infection in general following spinal surgery and the prevention of discitis specifically following procedures involving one or more discs. The roles of intraoperative antibiotic or antiseptic wound irrigation and drains in patients undergoing spinal surgery are also reviewed. Prophylaxis for patients undergoing spinal implant procedures will be addressed in a subsequent Working Party report dedicated to implant-associated infections.

Use of antibiotics in penetrating craniocerebral injuries

Summary The Working Party was instituted to investigate the rationale of prophylactic and therapeutic antibiotic use in penetrating craniocerebral injuries (PCCI), and to make recommendations for current practice. A systematic review of papers on civilian and military PCCI over the past 25 and 50 years, respectively, was done via electronic databases and secondary sources, and data were evaluated. Guidelines on the removal of indriven bone or metal fragments only if further neural damage can be avoided were supported. However, no publications were identified where the data on infection or its treatment and prevention were complete or satisfactorily derived, and no controlled trials have been published. All studies were retrospective or anecdotal. Working Party recommendations are based on the data available and the professional experience and knowledge of the members. Broad-spectrum antibiotic prophylaxis is recommended for both military and civilian PCCI, including those due to sports or recreational injuries.

Intracranial meningiomas following irradiation-a growing problem?

We present 10 cases of meningiomas occurring after high-dose irradiation for other brain tumours. These constitute 3.7% of 272 patients with meningiomas treated in our unit over 10 years. The clinical and pathological features of the 10 cases were added to those of 69 previous cases documented in the literature and compared with the features of our 262 spontaneous meningiomas. The literature on 119 cases of low-dose radiation-induced meningiomas was also reviewed. Malignant histological features and multiplicity were more common in the radiation-induced meningiomas (p < 0.01). Increasing long-term survival rates following radiotherapy for primary intracranial tumours, particularly in childhood, may lead to an increased incidence of postirradiation meningiomas.

Chronic hydrocephalus in adults

Chronic hydrocephalus is a complex condition, the incidence of which increases with increasing age. It is characterised by the presence of ventricular enlargement in the absence of significant elevations of intracranial pressure. The clinical syndrome may develop either as a result of decompensation of a “compensated” congenital hydrocephalus, or it may arise de novo in adult life secondary to a known acquired disturbance of normal CSF dynamics. The latter may be due to late onset acqueductal stenosis or disruption of normal CSF absorptive pathways following subarachnoid hemorrhage or meningitis (“secondary” normal pressure hydrocephalus (NPH)). In some cases the cause of the hydrocephalus remains obscure (“idiopathic” NPH). In all forms of chronic hydrocephalus the clinical course of the disease is heavily influenced by changes in the brain associated with aging, in particular cerebrovascular disease. Recent research has challenged previously held tenets regarding the CSF circulatory system and this in turn has led to a radical rethinking of the pathophysiological basis of chronic hydrocephalus.

The management of neurosurgical patients with postoperative bacterial or aseptic meningitis or external ventricular drain-associated

This article is dedicated to the management of neurosurgical patients who develop postoperative meningitis or external ventricular drain (EVD)-related ventriculitis. Postoperative meningitis is either bacterial or aseptic, the latter occurring more commonly. However, owing to difficulties associated with distinguishing between the two processes, all patients with the clinical and laboratory features of postoperative meningitis should receive empirical antibiotic therapy; if a cultured sample of CSF is sterile after incubation for 3 days, the antibiotics can be discontinued. Patients with confirmed bacterial meningitis should be treated with one of the organism-specific regimens provided. Also provided are recommendations for the management of patients with EVD-related ventriculitis and a strategy for preventing shunt infections in patients with EVDs who undergo implantation of CSF shunts.This article is dedicated to the management of neurosurgical patients who develop postoperative meningitis or external ventricular drain (EVD)-related ventriculitis. Postoperative meningitis is either bacterial or aseptic, the latter occurring more commonly. However, owing to difficulties associated with distinguishing between the two processes, all patients with the clinical and laboratory features of postoperative meningitis should receive empirical antibiotic therapy; if a cultured sample of CSF is sterile after incubation for 3 days, the antibiotics can be discontinued. Patients with confirmed bacterial meningitis should be treated with one of the organism-specific regimens provided. Also provided are recommendations for the management of patients with EVD-related ventriculitis and a strategy for preventing shunt infections in patients with EVDs who undergo implantation of CSF shunts.

The rational use of antibiotics in the treatment of brain abscess

The Working Party was instituted to investigate the rationale of therapeutic antibiotic usage in patients with brain abscess and to make recommendations for current practice. A systematic review of English language publications on brain abscess over the last 25 years was carried out using electronic databases and secondary sources, and data were evaluated. Few publications were identified where the microbiological procedures were adequately described and many authors continue to report sterile pus in a proportion of cases. The vast majority of reports were retrospective neurosurgical assessments in which details of laboratory procedures and antibiotic regimens were missing. There are no published reports of controlled clinical trials or comparative therapeutic studies. The recommendations made by the Working Party are based on relevant published information and the expertise of Working Party members. Recommendations vary according to the location of the abscess which reflects the likely source of the infection and therefore the bacterial types most likely to be present in aspirated pus. Bacteria with multiple resistance to antimicrobial agents do not feature significantly in cases of brain abscess.The Working Party was instituted to investigate the rationale of therapeutic antibiotic usage in patients with brain abscess and to make recommendations for current practice. A systematic review of English language publications on brain abscess over the last 25 years was carried out using electronic databases and secondary sources, and data were evaluated. Few publications were identified where the microbiological procedures were adequately described and many authors continue to report sterile pus in a proportion of cases.The vast majority of reports were retrospective neurosurgical assessments in which details of laboratory procedures and antibiotic regimens were missing.There are no published reports of controlled clinical trials or comparative therapeutic studies.The recommendations made by the Working Party are based on relevant published information and the expertise of Working Party members. Recommendations vary according to the location of the abscess which reflects the likely source of the infection and therefore the bacterial types most likely to be present in aspirated pus. Bacteria with multiple resistance to antimicrobial agents do not feature significantly in cases of brain abscess.