Cerebrospinal fluid cell count variability is a major confounding factor in external ventricular drain-associated infection surveillance diagnostics: a prospective observational study.

BACKGROUND: External ventricular drain (EVD)-related infections (EVDIs) are feared complications that are difficult to rapidly and correctly diagnose, which can lead to unnecessary treatment with broad-spectrum antibiotics. No readily available diagnostic parameters have been identified to reliably predict or identify EVDIs. Moreover, intraventricular hemorrhage is common and affect cerebrospinal fluid (CSF) cellularity. The relationship between leukocytes and erythrocytes is often used to identify suspected infection and triggers the use of antibiotics pending results of cultures, which may take days. Cell count based surveillance diagnostics assumes a homogeneous distribution of cells in the CSF. Given the intraventricular sedimentation of erythrocytes on computed tomography scans this assumption may be erroneous and could affect diagnostics. AIMS: To evaluate the consistency of cell counts in serially sampled CSF from EVDs, with and without patient repositioning, to assess the effect on infection diagnostics. METHODS: We performed a prospective single-center study where routine CSF sampling was followed by a second sample after 10 min, allocated around a standard patient repositioning, or not. Changes in absolute and pairwise cell counts and ratios were analyzed, including mixed regression models. RESULTS: Data from 51 patients and 162 paired samples were analyzed. We observed substantial changes in CSF cellularity as the result of both resampling and repositioning, with repositioning found to be an independent predictor of bidirectional cellular change. Glucose and lactate levels were affected, however clinically non-significant. No positive CSF cultures were seen during the study. Thirty percent (30%) of patients changed suspected EVDI status, as defined by the cell component of local and national guidelines, when resampling after repositioning. CONCLUSIONS: CSF cell counts are not consistent and are affected by patient movement suggesting a heterogeneity in the intraventricular space. The relationship between leukocytes and erythrocytes was less affected than absolute changes. Importantly, cell changes are found to increase with increased cellularity, often leading to changes in suspected EVDI status. Faster and more precise diagnostics are needed, and methods such as emerging next generation sequencing techniques my provide tools to more timely and accurately guide antibiotic treatment. Trial Registration NCT04736407, Clinicaltrials.gov, retrospectively registered 2nd February 2021.

Bilateral External Ventricular Drains Increase Ventriculostomy-Associated Cerebrospinal Fluid Infection in Low Modified Graeb Score Intraventricular Hemorrhage.

BACKGROUND: Ventriculostomy-associated cerebrospinal fluid infection (VAI) is a major complication limiting the use of an external ventricular drain (EVD) in treating patients with intraventricular hemorrhage (IVH). Risk factors of VAI are still under wide discussion. METHODS: We performed a retrospective review of 84 patients with IVH who underwent EVD at our center between January 2012 and January 2017. Preoperative clinical parameters, surgeon status, number of catheters and catheter-days, subgaleal tunneling distance, frequency of urokinase flush, and prophylactic antibiotics were compared between the infective and noninfective groups. RESULTS: The overall rate of VAI was 31.0%. Univariate analysis showed a higher modified Graeb Score (mGS), higher proportion of bilateral catheters, and longer hospital stay in patients with VAI. Binary logistic analysis of all clinical factors identified high mGS (≥16) as an independent risk factor for VAI (odds ratio, 3.242; P = 0.026). Among operative and postoperative factors, the use of bilateral catheters significantly contributed to VAI (odds ratio, 4.211; P = 0.031), but a subgroup comparison showed an increased VAI rate only in the low mGS group (mGS <15). No VAI occurred in patients with a single EVD in the low mGS group. Catheter-days and multiple urokinase flushes were not related to VAI. CONCLUSIONS: Patients with a high mGS are vulnerable to VAI. Bilateral EVD may be an appropriate treatment option for patients with a high mGS, but might increase the risk of infection in those with a low mGS.

[Cerebrospinal fluid shunt malfunction not associated with ventricular enlargement. A case report and literature review]. / Disfunktsiya shunta tserebrospinal'noi zhidkosti bez rasshireniya zheludochkov mozga. Sluchai iz praktiki i obzor literatury.

Substantiation of the shunt failure diagnosis and subsequent consideration of indications for surgical elimination of the malfunction is a laborious and challenging process. Identification of a malfunction in doubtful cases requires, in addition to standard examinations, extra diagnostic procedures, which may delay making a decision for several weeks to several months. The article describes a case of mechanical CSF shunt malfunction (breakage and failure of a peritoneal catheter in a 7-year-old girl) with intracranial hypertension symptoms, but without typical enlargement of the brain ventricles. According to the medical history, congenital hydrocephalus in the child was accompanied by an inflammatory process of bacterial and viral etiology. The absence of brain ventricle enlargement was shown not to exclude a probability of shunt malfunction. In this case, a specific phenomenon, an intraparenchymatous cerebrospinal fluid "lake" surrounding a ventricular catheter, was observed. Shunting recovery did not lead to a significant reduction in the phenomenon size. Causes underlying this phenomenon require further investigation.

From the Skin to the Brain: Pathophysiology of Colonization and Infection of External Ventricular Drain, a Prospective Observational Study.

Ventriculostomy-related infection (VRI) is a serious complication of external ventricular drain (EVD) but its natural history is poorly studied. We prospectively tracked the bacteria pathways from skin towards ventricles to identify the infectious process resulting in ventriculostomy-related colonization (VRC), and VRI. We systematically sampled cerebrospinal fluid (CSF) on a daily basis and collected swabs from both the skin and stopcock every 3.0 days for microbiological analysis including in 101 neurosurgical patient. Risk factors for positive event defined as either VRC or VRI were recorded and related to our microbiological findings. A total of 1261 CSF samples, 473 skin swabs, and 450 stopcock swabs were collected. Skin site was more frequently colonized than stopcock (70 (60%) vs 34 (29%), p = 0.023), and earlier (14 ±1.4 vs 24 ±1.5 days, p<0.0001). Sixty-one (52%) and 32 (27%) skin and stopcock sites were colonized with commensal bacteria, 1 (1%) and 1 (1%) with pathogens, 8 (7%) and 1 (1%) with combined pathogens and commensal bacteria, respectively. Sixteen positive events were diagnosed; a cutaneous origin was identified in 69% of cases. The presence of a pathogen at skin site (6/16 vs 4/85, OR: 11.8, [2.5-56.8], p = 0.002) and CSF leakage (7/16 vs 6/85, OR 10 [2.4-41.2], p = 0.001)) were the two independent significant risk factors statistically linked to positive events occurrence. Our results suggest that VRC and VRI mainly results from an extra-luminal progression of pathogens initially colonizing the skin site where CSF leaks.

Predictive factors of the outcome and intraventricular rupture of brain abscess.

OBJECTIVE: To identify the significant factors predicting afavorable outcome and to study clinical characteristics and identify the factors predicted by intraventricular rupture of brain abscess (IVROBA). MATERIAL AND METHOD: In the retrospective study, the computer-based medical records of patients of a tertiary care hospital between 1999 and 2013 were reviewed. Univariate and multivariate analyses were used to determine the significant factors predicting the outcomes and IVROBA. RESULTS: One hundred fourteen patients with brain abscesses were enrolled. The predictivefactor of a favorable outcome was Glasgow Coma Scale (GCS) score 13 to 15 (OR 14.64; 95% CI 2.70-79.34; p = 0.02). Conversely, the factors associated with an unfavorable outcome were fungal brain abscess (OR 40.81; 95% CI 3.57-466.49; p = 0.003) and IVROBA (OR 5.50; 95% CI 1.34-22.49; p = 0.017). Moreover greater distance of the brain abscess from the ventricle decreased the IVROBA (OR 0.62; 95% CI 0.45-0.87; p = 0.005). Abscesses with intraventricular rupture that were at less than 7 mm of a ventricle (p < 0.000) were likely to IVROBA. CONCLUSION: The outcome of a brain abscess depends on good clinical status, pathogens, and fatal complication of lVROBA. If poor prognostic factors exist, then better surgical option can be selected.

Intraventricular granulomatous mass associated with Mycobacterium haemophilum: A rare central nervous system manifestation in a patient with human immunodeficiency virus infection.

We report a rare case of Mycobacterium haemophilum presenting as an intraventricular granulomatous mass with loculated hydrocephalus and seizures in a patient with human immunodeficiency virus. M. haemophilum, a slow-growing mycobacteria, causes localized and disseminated disease among immunocompromised hosts. Central nervous system infection with M. haemophilum is extremely rare. Preoperative laboratory testing of our patient for tuberculosis, toxoplasmosis, sarcoidosis and histoplasmosis were negative. Surgical resection of the mass revealed a caseating granuloma that stained positive for acid-fast bacillus suggesting possible tuberculoma. Despite negative testing for tuberculosis, a polymerase chain reaction analysis was ultimately performed from the resected mass which revealed M. haemophilum. To our knowledge, this is the first case of M. haemophilum presenting as an intraventricular mass. We review the clinical manifestations of this pathogen and discuss the medical and surgical management.

A rare case of an isolated intraventricular tuberculoma with a dismal outcome: an unusual location of a common pathology and lessons learnt.

Isolated involvement of the ventricle by tuberculosis is extremely rare and only nine cases have been reported till now. We report a 13-year-old immuno-competent boy who presented with features of raised intracranial pressure with altered sensorium. Computed Tomography showed a ring enhancing intraventricular lesion with obstructive hydrocephalus. Gross total resection of the lesion was achieved and diagnosis was confirmed histologically. The patient had medical complications in the postoperative period and succumbs five days after the surgery. This report presents the unusual location of a common disease with a review of its clinical, radiological and histopathological features as well as the treatment modalities available.

Shunt-dependent hydrocephalus after aneurysmal subarachnoid hemorrhage: the role of intrathecal interleukin-6.

OBJECT: Aneurysmal subarachnoid hemorrhage (SAH) has been reported to induce an intrathecal inflammatory reaction reflected by cytokine release, particularly interleukin-6 (IL-6), which correlates with early brain damage and poor outcome. The present study examines intrathecal IL-6 production together with clinical parameters, as a predictor of posthemorrhagic shunt dependency. METHODS: Among 186 SAH patients admitted between July 2010 and December 2012, 82 received external ventricular drainage due to acute hydrocephalus. In these patients, cerebrospinal fluid (CSF) concentrations of IL-6 were measured within the first 14 days after SAH. Patients whose IL-6 values were not determined regularly and those who did not survive until discharge were excluded. The peak value of IL-6, ventricular infection during the hospital stay, microbial CSF culture, patient's age and sex, Hunt and Hess grade, and aneurysm location were assumed as predictive for shunt dependency. RESULTS: Sixty-nine patients were included, 24 of whom underwent shunt surgery. Peak IL-6 values of ≥10,000 pg/ml were significantly associated with a higher incidence of shunt dependency (p = 0.009). Additional risk factors were aneurysm location on the anterior cerebral artery and its branches or in the posterior circulation (p = 0.025), and age ≥60 years (p = 0.014). In a multivariate analysis, IL-6 ≥10,000 pg/ml appeared to be the only independent predictor for shunt dependency (p = 0.029) CONCLUSION: CSF IL-6 values of ≥10,000 pg/ml in the early post-SAH period may be a useful diagnostic tool for predicting shunt dependency in patients with acute posthemorrhagic hydrocephalus. The development of shunt-dependent posthemorrhagic hydrocephalus remains a multifactorial process.

Use of a cyanoacrylate skin adhesive to reduce external ventricular drain infection rates.

UNLABELLED: OBJECT.: Ventriculitis related to external ventricular drain (EVD) placement is a significant source of morbidity in neurological intensive care patients. Current rates of EVD-related infections range from 2% to 45% in the literature. The authors sought to determine if a 2-octyl cyanoacrylate adhesive would result in lower infection rate than standard semiocclusive dressings. METHODS: The authors tracked ventriculitis rates via CSF cultures among 259 patients whose EVD sites were dressed with sterile semiocclusive dressings and underwent routine sterile dressing exchanges every 48 hours. They analyzed data obtained in an additional 113 patients whose EVD sites were dressed one time with a surgical adhesive, 2-octyl cyanoacrylate. RESULTS: Ventriculitis rate in patients with standard bioocclusive dressings and wound care was 15.1%, whereas that in patients with a 2-octyl cyanoacrylate dressing was 3.54% (p = 0.002). Staphylococcus genus accounted for 79.5% of instances of ventriculitis among patients with bioocclusive dressings and routine wound care, whereas it accounted for 25.0% of the instances of ventriculitis among patients with a liquid polymer sealant dressing. A 90% reduction in Staphylococcus infection completely accounts for the observed effect (p = 0.04). CONCLUSIONS: The one-time application of 2-octyl cyanoacrylate to EVD wounds and exit sites provided superior protection against EVD-related ventriculitis compared to conventional EVD-site wound care. Likely this protection results from a barrier to the entry of gram-positive skin flora along the EVD exit tract. The results should be validated in a randomized trial.

Clinical review: Efficacy of antimicrobial-impregnated catheters in external ventricular drainage - a systematic review and meta-analysis.

To assess the efficacy of antimicrobial-impregnated catheters in preventing catheter-related infections during external ventricular drainage (EVD), we performed a meta-analysis and systematic review. We systematically searched Medline, Embase, and the Cochrane Library. All randomized controlled trials (RCTs) and nonrandomized prospective studies (NPSs) related to antimicrobial-impregnated EVD catheters were included. The primary outcome was the rate of cerebrospinal fluid infection (CFI). The secondary outcomes included the rate of time-dependent CFI and catheter bacterial colonization. We further performed subgroup analysis, meta-regression analysis, and microbial spectrum analysis. Four RCTs and four NPSs were included. The overall rate of CFIs was 3.6% in the antimicrobial-impregnated catheter group and 13.7% in the standard catheter group. The pooled data demonstrated that antimicrobial-impregnated catheters were superior to standard catheters in lowering the rate of CFIs (odds ratio (OR) = 0.25, 95% confidence interval (CI) = 0.12 to 0.52, P <0.05). In survival analysis, the 20-day infection rate was significantly reduced with the use of antimicrobial-impregnated catheters (hazard ratio = 0.52, 95% CI = 0.29 to 0.95, P <0.05). Furthermore, a significantly decreased rate of catheter bacterial colonization was noticed for antimicrobial-impregnated catheters (OR = 0.37, 95% CI = 0.21 to 0.64, P <0.05). In subgroup analyses, although significant results remained for RCTs and NPSs, a subgroup difference was revealed (P <0.05). Compared with standard catheters, a significantly lower rate of CFIs was noticed for clindamycin/rifampin-impregnated catheters (OR = 0.27, 95% CI = 0.10 to 0.73, P <0.05) and for minocycline/rifampin-impregnated catheters (OR = 0.11, 95% CI = 0.06 to 0.21, P <0.05). However, no statistical significance was found when compared with silver-impregnated catheters (OR = 0.33, 95% CI = 0.07 to 1.69, P = 0.18). In microbial spectrum analysis, antimicrobial-impregnated catheters were shown to have a lower rate of Gram-positive bacterial infection, particularly the coagulase-negative Staphylococcus. In conclusion, the use of antimicrobial-impregnated EVD catheters could be beneficial for the prevention of CFI and catheter bacterial colonization. Although antibiotic-coated catheters seem to be effective, no sufficient evidence supports the efficacy of silver-impregnated catheters.

Antibiotic-impregnated versus silver-bearing external ventricular drainage catheters: preliminary results in a randomized controlled trial.

BACKGROUND: Evaluation of antibiotic-impregnated (AI) and ionized silver particle coated external ventricular drainage catheters (EVD) in patients with subarachnoid (SAH) or intracranial hemorrhage (ICH). METHODS: Between February 2011 and June 2012, 40 patients with acute hydrocephalus due to SAH, ICH or intraventricular hemorrhage were enrolled in a prospective, randomized, mono-center pilot study. Primary endpoints were defined as: number of events of cerebrospinal fluid (CSF) infections. Secondary endpoints were defined as: neurosurgical complications following the placement of the EVD, number of revisions of EVD catheters, and cost effectiveness. RESULTS: Sixty-one EVD placements in 40 patients, 32 antibiotic-coated (Bactiseal(®)), 29 silver-bearing catheters (VentriGuard(®)), have been performed. Confirmed or high suspicion of CSF infections occurred in 11 out of 61 events (confirmed infection: p = 0.71, probable infection: p = 0.90). Revisions of EVD were needed in 13 cases (22 %) due to CSF infection, dysfunction, impaired healing, or malplacement (p = 0.37). CONCLUSION: Regarding CSF infection rate and dysfunction, no statistical significant differences between the two EVD catheters Bactiseal(®) versus VentriGuard(®) were found. The silver-bearing catheter might offer a safe and cost-conscious alternative to the AI catheter.

Impact of an educational intervention implanted in a neurological intensive care unit on rates of infection related to external ventricular drains.

BACKGROUND: Studies on the implantation of care routines showed reduction on EVD catheter-related infections rates; however zero tolerance is difficult to be achieved. The objective of this study was to assess the impact of an educational intervention on the maximal reduction on rates of EVD-related infections. METHODOLOGY/PRINCIPAL FINDINGS: The quasi-experimental (before-after intervention) study occurred in two phases: pre-intervention, from April 2007 to July 2008, and intervention, from August 2008 to July 2010. Patients were followed for 30 days after the removal of the EVD, and EVD-related infections were considered as only those with laboratorial confirmation in the CSF. Observations were made of the care of the EVD and compliance with Hygiene of the Hands (HH), a routine of care was drawn up, training was given, and intervention was made to reduce the time the EVD catheter remained in place. RESULTS: during the study, 178 patients were submitted to 194 procedures, corresponding to 1217 EVD catheters-day. Gram-negative agents were identified in 71.4% of the infections during the pre-intervention period and in 60% during the intervention period. During the study, EVD-related infection rates were reduced from 9.5% to 4.8% per patient, from 8.8% to 4.4% per procedure, and the incidence density dropped from 14.0 to 6.9 infections per 1000 catheters-day (p = 0.027). The mortality reduced 12% (from 42% to 30%). CONCLUSIONS/SIGNIFICANCE: During one year after the fourth intervention, no microbiologically identified infection was documented. In light of these results, educational intervention proved to be a useful tool in reducing these rates and showed also impact on mortality.

Staphylococcus aureus sarA regulates inflammation and colonization during central nervous system biofilm formation.

Infection is a frequent and serious complication following the treatment of hydrocephalus with CSF shunts, with limited therapeutic options because of biofilm formation along the catheter surface. Here we evaluated the possibility that the sarA regulatory locus engenders S. aureus more resistant to immune recognition in the central nervous system (CNS) based on its reported ability to regulate biofilm formation. We utilized our established model of CNS catheter-associated infection, similar to CSF shunt infections seen in humans, to compare the kinetics of bacterial titers, cytokine production and inflammatory cell influx elicited by wild type S. aureus versus an isogenic sarA mutant. The sarA mutant was more rapidly cleared from infected catheters compared to its isogenic wild type strain. Consistent with this finding, several pro-inflammatory cytokines and chemokines, including IL-17, CXCL1, and IL-1ß were significantly increased in the brain following infection with the sarA mutant versus wild type S. aureus, in agreement with the fact that the sarA mutant displayed impaired biofilm growth and favored a planktonic state. Neutrophil influx into the infected hemisphere was also increased in the animals infected with the sarA mutant compared to wild type bacteria. These changes were not attributable to extracellular protease activity, which is increased in the context of SarA mutation, since similar responses were observed between sarA and a sarA/protease mutant. Overall, these results demonstrate that sarA plays an important role in attenuating the inflammatory response during staphylococcal biofilm infection in the CNS via a mechanism that remains to be determined.

Purulent meningoventriculitis caused by Streptococcus equi subspecies zooepidemicus in a snow leopard (Panthera uncia).

Streptococcus equi subspecies zooepidemicus (SEZ) is a zoonotic pathogen that causes respiratory tract infections in man and animals. SEZ infections are very rare in felids. This report describes purulent meningoventriculitis caused by SEZ in an approximately 16-year-old male snow leopard (Panthera uncia). The animal exhibited neurological signs and died 1 month after their onset. On necropsy examination, the surface blood vessels of the brain were swollen and there was an increased volume and turbidity of cerebrospinal fluid (CSF). Microscopically, suppurative inflammation accompanied by gram-positive cocci was observed in the meninges and near the ventricles. SEZ was isolated from the brain tissue and CSF. This is the first report of infection with SEZ in a felid other than a domestic cat. This animal had not had direct contact with horses, but it had been fed horse flesh that may have been the source of infection.

Evaluation of cerebrospinal fluid parameters in preterm infants with intraventricular reservoirs.

OBJECTIVE: Intraventricular reservoirs (IVRs) are used to drain cerebrospinal fluid (CSF) in neonates with post-hemorrhagic ventricular dilatation (PHVD). The objectives of this case-control study were to evaluate changes in CSF parameters in serial IVR taps and to compare CSF parameters in culture-positive and -negative specimens. STUDY DESIGN: Clinical and laboratory data from serial (up to 7) reservoir taps at 5- to 8-day intervals were collected on preterm neonates with PHVD and IVR insertion. RESULT: The median (range) gestational age and birth weight of our cohort (n=52) was 26 (23 to 33) weeks and 796 (450 to 1620) grams. Significant decreases in percentage of CSF neutrophils and protein were noted in later taps, compared with the first tap at insertion of IVR. Five (9.6%) infants had positive CSF cultures on 10 occasions. Compared with negative specimens (n=266), the mean (s.d.) proportion of neutrophils in CSF (55% (33) vs 26% (23)) was significantly higher and ratio of CSF to serum glucose significantly lower (0.19 (0.08) vs 0.29 (0.13)) in culture-positive specimens (n=10). The area under the curve was 0.82 (95% confidence interval (CI) 0.72 to 0.93) for CSF white blood cell (WBC) count, 0.79 (95% CI 0.68 to 0.90) for CSF protein and 0.75 (95% CI 0.56 to 0.95) for percentage of neutrophils. The sensitivities and specificities for diagnosis of infection was 90 and 63% for CSF WBC count > 42 mm(-3), 89 and 58% for CSF protein at > 250 mg dl(-1) and 80 and 67% for CSF neutrophil proportion >31.5%. CONCLUSION: CSF parameters from IVR taps, specifically proportion of neutrophils and proteins are higher at insertion and progressively normalize over time. Although they vary widely, CSF WBC, protein and neutrophil proportion using higher cut-off values have good sensitivity in the diagnosis of infection.

Stereotactic drainage of empyema of the cavum septi pellucidi et vergae.

BACKGROUND: Persistent midline ventricular cavae may only rarely cause clinical symptoms. Exceptionally, empyemas may develop in these cavae. Optimal treatment has been defined only poorly so far. METHODS: Here, we report successful treatment of a bacterial empyema in the cavum septi pellucidi et vergae due to sphenoid sinus sinusitis in a 36-year-old woman by stereotactic puncture and drainage of the empyema and long-term administration of antibiotics. RESULTS AND CONCLUSIONS: Stereotactic puncture and drainage accompanied by antibiotic therapy result in beneficial outcome in the long term. Transcallosal interhemispheric approaches and free-hand techniques should be discouraged since, according to previously published reports, they may result in severe morbidity or mortality in this condition.

Neuroendoscopic diagnosis of central nervous system histoplasmosis with basilar arachnoiditis.

OBJECTIVE: Histoplasmosis of the central nervous system (CNS) is seen in 10% to 20% of patients with disseminated histoplasmosis and/or in association with immunocompromised patients. Meningitis, arachnoiditis, and hydrocephalus are the most common clinical manifestations of CNS histoplasmosis. Patients with CNS histoplasmosis present similarly to other infectious etiologies, and confirmatory diagnosis is important in the management of these patients. However, diagnosis of CNS histoplasmosis can be difficult, and sometimes performing a parenchymal biopsy is necessary to confirm the diagnosis. METHODS AND RESULTS: We describe the case of a 41-year-old man with HIV/AIDS who presented with the signs, symptoms, and radiologic evidence of basal meningitis and hydrocephalus. Cerebrospinal fluid (CSF) analysis from multiple lumbar punctures was negative. The patient underwent a neuroendoscopic procedure with diagnostic and therapeutic goals. Internal CSF diversion (endoscopic third ventriculostomy) and biopsy of the floor of the third ventricle and subarachnoid space were performed; surgical biopsies identified noncaseating granulomas, and ventricular CSF was positive for Histoplasmosis antibodies. The patient was treated with liposomal amphotericin B and itraconazole. The patient had resolution of his symptoms immediately after surgery, and 1-month follow-up computed tomography of the head demonstrated resolution of the hydrocephalus. At the last follow-up 12 months postoperatively, the patient has not required insertion of a ventriculoperitoneal shunt. CONCLUSION: Clinicians should maintain a high index of suspicion for fungal basal meningitis in patients with AIDS and hydrocephalus. With nondiagnostic lumbar CSF sampling, neuroendoscopy can be considered as an alternative for diagnosis and treatment of basal meningitis and hydrocephalus.