The Impact of Multimorbidity Burden, Frailty Risk Scoring, and 3-Directional Morphological Indices vs. Testing for CSF Responsiveness in Normal Pressure Hydrocephalus

Objective: Multimorbidity burden across disease cohorts and variations in clinico-radiographic presentations within normal pressure hydrocephalus (NPH) confound its diagnosis, and the assessment of its amenability to interventions. We hypothesized that novel imaging techniques such as 3-directional linear morphological indices could help in distinguishing between hydrocephalus vs. non-hydrocephalus and correlate with responsiveness to external lumbar drainage (CSF responsiveness) within NPH subtypes.Methodology: Twenty-one participants with NPH were recruited and age-matched to 21 patients with Alzheimer’s Disease (AD) and 21 healthy controls (HC) selected from the Alzheimer’s Disease Neuroimaging Initiative (ADNI) database. Patients with NPH underwent testing via the NPH programme with external lumbar drainage (ELD); pre- and post-ELD MRI scans were obtained. The modified Frailty Index (mFI-11) was used to stratify the NPH cohort, including Classic and Complex subtypes, by their comorbidity and frailty risks. The quantitative imaging network tool 3D Slicer was used to derive traditional 2-dimensional (2d) linear measures; Evans Index (EI), Bicaudate Index (BCI) and Callosal Angle (CA), along with novel 3-directional (3d) linear measures; z-Evans Index and Brain per Ventricle Ratio (BVR). 3-Dimensional (3D) ventricular volumetry was performed as an independent correlate of ventriculomegaly to CSF responsiveness.Results: Mean age for study participants was 71.14 ± 6.3 years (18, 85.7% males). The majority (15/21, 71.4%) of participants with NPH comprised the Complex subtype (overlay from vascular risk burden and AD); 12/21 (57.1%) were Non-Responders to ELD. Frailty alone was insufficient in distinguishing between NPH subtypes. By contrast, 3d linear measures distinguished NPH from both AD and HC cohorts, but also correlated to CSF responsiveness. The z-Evans Index was the most sensitive volumetric measure of CSF responsiveness (p = 0.012). Changes in 3d morphological indices across timepoints distinguished between Responders vs. Non-Responders to lumbar testing. There was a significant reduction of indices, only in Non-Responders and across multiple measures (z-Evans Index; p = 0.001, BVR at PC; p = 0.024). This was due to a significant decrease in ventricular measurement (p = 0.005) that correlated to independent 3D volumetry (p = 0.008).Conclusion. In the context of multimorbidity burden, frailty risks and overlay from neurodegenerative disease, 3d morphological indices demonstrated utility in distinguishing hydrocephalus vs. non-hydrocephalus and degree of CSF responsiveness. Further work may support the characterization of patients with Complex NPH who would best benefit from the risks of interventions.

Is Lumbar Puncture Needed? – Noninvasive Assessment of ICP Facilitates Decision Making in Patients with Suspected Idiopathic Intracranial Hypertension

Purpose Idiopathic intracranial hypertension (IIH) usually occurs in obese women of childbearing age. Typical symptoms are headache and sight impairment. Lumbar puncture (LP) is routinely used for both diagnosis and therapy (via cerebrospinal fluid drainage) of IIH. In this study, noninvasively assessed intracranial pressure (nICP) was compared to LP pressure (LPP) in order to clarify its feasibility for the diagnosis of IIH. Materials and Methods nICP was calculated using continuous signals of arterial blood pressure and cerebral blood flow velocity in the middle cerebral artery, a method which has been introduced recently. In 26 patients (f = 24, m = 2; age: 33 ± 11 years), nICP was assessed one hour prior to LPP. If LPP was > 20 cmH2O, lumbar drainage was performed, LPP was measured again, and also nICP was reassessed. Results In total, LPP and nICP correlated with R = 0.85 (p < 0.001; N = 38). The mean difference of nICP-LPP was 0.45 ± 4.93 cmH2O. The capability of nICP to diagnose increased LPP (LPP > 20 cmH2O) was assessed by ROC analysis. The optimal cutoff for nICP was close to 20 cmH2O with both a sensitivity and specificity of 0.92. Presuming 20 cmH2O as a critical threshold for the indication of lumbar drainage, the clinical implications would coincide in both methods in 35 of 38 cases. Conclusion The TCD-based nICP assessment seems to be suitable for a pre-diagnosis of increased LPP and might eliminated the need for painful lumbar puncture if low nICP is detected.

A Controlled Study of Continuous Lumbar Drainage of Fluid and Lumbar Puncture Drainage for Aneurysmal SAH after Intracranial Aneurysm Clipping

Objective. To analyze the different effects of Continuous Lumbar Drainage of fluid and lumbar puncture drainage for aneurysmal subarachnoid hemorrhage (SAH) after intracranial aneurysm clipping. Method. Seventy-five patients with aneurysmal SAH who underwent aneurysm clipping were retrospectively analyzed and were divided into two groups according to the different postoperative drainage methods. The lumbar spine group received lumbar puncture drainage, and the lumbar cistern group received lumbar pool continuous drainage to compare the efficacy. Result. The time to normalize intracranial pressure and headache relief after drainage treatment in the lumbar cistern group was shorter than that in the lumbar spine group. The GOS score was higher than that in the lumbar spine group, and the cerebral artery flow velocity and NIHSS score were significantly lower than those in the lumbar spine group ( P < 0.05 ). The total effective rate of drainage treatment was 76.32% in the lumbar cistern group, which was higher than that in the lumbar spine group (54.05%) ( P < 0.05 ). The total complication rate was 18.42% in the lumbar cistern group, which was lower than that in the lumbar spine group (40.54%) ( P < 0.05 ). Conclusion. Continuous Lumbar Drainage of fluid after intracranial aneurysm clipping for aneurysmal SAH can control symptoms more rapidly, reduce neurological deficits, and improve prognosis than lumbar puncture. Also, the drainage is safer and more widely used.

External Lumbar Drainage for Refractory Intracranial Hypertension in Traumatic Brain Injury: A Systematic Review

BackgroundExternal lumbar drainage remains a controversial therapy for medically refractory intracranial hypertension in patients with acute TBI. This systematic review sought to compile the available evidence for the efficacy and safety of the use of lumbar drains for ICP control. MethodsA systematic review of the literature was performed with the search and data extraction performed by two reviewers independently in duplicate.ResultsNine independent studies were identified enrolling 230 patients, 159 with TBI. Efficacy for ICP control was observed across all studies, with immediate and sustained effect, reducing medical therapy requirements. Lumbar drainage with medical therapy appears effective when used alone and as an adjunct to ventricular drainage. Safety reporting varied in quality. Cerebral herniation (with unclear relationship to lumbar drainage) was observed in 14/230 patients resulting in one incident of morbidity without adverse patient outcome. ConclusionsThe available data is generally poor in quality and volume, but supportive of efficacy of lumbar drainage for ICP control. Few reports of adverse outcome are suggestive of, but are insufficient to confirm, safety of use in the appropriate patient and clinical setting. Further large prospective observational studies are required to generate sufficient support of an acceptable safety profile.

External lumbar drainage in progressive pediatric idiopathic intracranial hypertension

OBJECTIVE Pediatric idiopathic intracranial hypertension (IIH) is characterized by increased intracranial pressure despite normal cerebrospinal fluid and neuroimaging findings. Initial management is typically medical; however, nearly 10% of children will eventually require surgery for persistent headache and/or vision loss. External lumbar drainage, which is a considerably safer treatment option, has not been adequately analyzed in children with medically refractory IIH. METHODS The authors conducted a single-institution retrospective analysis of children with medically refractory IIH who had undergone external lumbar drain (ELD) placement because of worsening papilledema, reflected as increased retinal nerve fiber layer (RNFL) thickness on optical coherence tomography (OCT) testing. The main outcome measures were effects of external lumbar drainage on papilledema resolution, symptoms, and vision. RESULTS The authors analyzed the medical records of 13 children with IIH (11 girls, mean age 15.0 ± 2.3 years) whose mean CSF opening pressure was 45.5 ± 6.8 cm H2O. In all children, the average global RNFL thickness in both eyes significantly increased at ELD placement (right eye 371.8 ± 150.2 μm, left eye 400.3 ± 96.9 μm) compared with presentation thickness (right eye 301.6 ± 110.40 μm, left eye 350.2 ± 107.7 μm) despite acetazolamide medical therapy (20–30 mg/kg/day), leading to ELD placement after 9.5 ± 6.9 days (range 3–29 days). After ELD insertion, there was headache resolution, gradual and continuous improvement in optic disc thickness, and preservation of good vision. CONCLUSIONS ELD placement in children with medically refractory IIH who demonstrated worsening papilledema with increased RNFL thickening on OCT testing typically results in symptom relief and disc edema resolution with good visual outcome, often preventing the need for additional definitive surgeries that carry greater failure and morbidity risks.

Endoscopic skull base reconstruction of large defects: retrospective analysis of 30 cases

Background. Endoscopic skull base reconstruction of large defects is a difficult issue in neurosurgery, as there are problems associated with a wide dural resection, intra-arachnoid dissection (due to removal of the meningocele or resection of an intracranially spreading tumor), and exposure to high-flow cerebrospinal fluid within the cisterns. But perhaps the most significant influence is the larger nonvascularized reconstructive bed – cerebrospinal fluid on one side and sinus cavity (air) on the other.The study objective is to analyze our own experience in treating patients with large defects of the skull base and, based on the results obtained, to optimize the method of reconstruction.Materials and methods. A retrospective analysis of 30 cases of reconstruction of large defects of skull base of various etiologies. The results of surgery in the early and late postoperative period were evaluated. Statistical analysis was carried out using the exact Fisher criterion and the analysis of arbitrary contingency tables using the chi-square criterion. A literature review was conducted to compare the data obtained with the results of other studies.Results. In the group of patients (n = 16) for whom reconstruction was performed only with free transplants the effectiveness of reconstruction was 75 %. In the group of patients (n = 14) who underwent the last stage of reconstruction using a vascularized pedicled nasoseptal flap, the plastic surgery efficiency was 100 %. According to statistical analysis, there is a relationship between the choice of transplant type and the multilayer technique (p <0.05). The use of lumbar drainage did not affect the recurrence of cerebrospinal fluid leak in the postoperative period (p >0.05).Conclusion. Endoscopic skull base reconstruction can be effectively used for defects of the skull base >1.5 cm. When choosing the technique of reconstruction of large defects of the skull base, preference should be given to multilayer plastic using vascularized flaps. The use of lumbar drainage for reconstruction of large defects is a justified method in the case of a clear definition of indications for its use, based on a comparison of the possible benefits and risks associated with the invasiveness of the method.