Faculty Bibliography

Background: To describe preliminary results of a multi-center, randomized, blinded, placebo-controlled, pilot trial of shunt surgery in INPH.
Method(s): Five sites randomized 18 patients scheduled for ventriculoperitoneal shunting based on CSF-drainage response. Patients were randomized to a Codman Certas Plus valve with SiphonGuard at either setting 4 (Active, N=9) or setting 8/virtual off (Placebo, N=9). Patients and assessors were blinded to the shunt setting. Outcomes included 10-meter gait velocity, cognitive function, and bladder activity scores. The prespecified primary analysis compared changes in 4-month gait velocity in the Active versus Placebo groups. After the 4 months follow up, all shunts were opened, i.e., adjusted to setting 4 whereafter patients underwent 8 and 12-month post-surgical assessment. At the 8-month follow-up, the Placebo group had had an open shunt for 4 months and the Active group for 8 months.
Result(s): At 4-months, gait velocity increased by 0.28+/-0.28m/s in the Active Group and 0.04+/-0.17m/s in the Placebo Group (p=0.071). Overactive Bladder (OAB-q) scores improved in the Active versus Placebo groups (p=0.007). At 8 months, Placebo gait velocity increased by 0.36+/-0.27m/s and was comparable to the Active Group (0.40+/-0.20m/s p=0.56).
Conclusion(s): This study shows a trend suggesting gait velocity improves more at an Active shunt setting than a Placebo shunt setting and demonstrates the feasibility of a placebo-controlled trial in iNPH

BACKGROUND:When appropriately selected, a high proportion of patients with suspected idiopathic normal pressure hydrocephalus (iNPH) will respond to cerebrospinal fluid diversion with a shunt. Extended lumbar drainage (ELD) is regarded as the most accurate test for this condition, however, varying estimates of its accuracy are found in the current literature. Here, we review the literature in order to provide summary estimates of sensitivity, specificity, positive- and negative predictive value for this test through meta-analysis of suitably rigorous studies. METHODS:Studies involving a population of NPH patients with predominantly idiopathic aetiology (>80%) in which the intention of the study was to shunt patients regardless of the outcome of ELD were included in the review. Various literature databases were searched to identify diagnostic test accuracy studies addressing ELD in the diagnosis of iNPH. Those studies passing screening and eligibility were assessed using the QUADAS-2 tool and data extracted for bivariate random effects meta-analysis. RESULTS:Four small studies were identified. They showed disparate results concerning diagnostic test accuracy. The summary estimates for sensitivity and specificity were 94% (CI 41-100%) and 85% (CI 33-100%), respectively. The summary estimates of positive and negative predictive value were both 90% (CIs 65-100% and 48-100%, respectively). CONCLUSION/CONCLUSIONS:Large, rigorous studies addressing the diagnostic accuracy of ELD are lacking, and little robust evidence exists to support the use of ELD in diagnostic algorithms for iNPH. Therefore, a large cohort study, or ideally an RCT, is needed to determine best practice in selecting patients for shunt surgery.

PURPOSE/OBJECTIVE:The Posterior Fossa Society (PFS) was founded 4 years ago to systematically gather and exchange information on the post-operative (CMS) and cerebellar cognitive affective syndrome (CCAS). With its consensus meetings, the PFS orchestrates research studies in the field of cerebellar injury and progresses the knowledge of post-operative pediatric cerebellar mutism syndrome (CMS). In this article, we captured the 3-day program of presentations, group discussions, interactive workshops, and dialogue, highlighting the key topic areas of CMS and its research advances. METHODS:This synopsis is based on the third consensus meeting which was held in Reykjavik, Iceland, in August 2018. RESULTS:Three working groups have been defined to drive the future research priorities on post-surgical CMS: (i) refining definition and symptoms scoring of CMS; (ii) understanding the pathogenesis and enhancing risk-stratification strategies; and (iii) developing rehabilitation approaches and protocols. CONCLUSIONS:The third consensus meeting highlighted a unanimous desire for data-driven information to advance the knowledge and guide future research efforts. The PFS constitutes an established and expanding network of multi-disciplinary expertise that can facilitate the development of collaborative studies and produce official guidelines on the topic.

BACKGROUND:New-onset hydrocephalus following foramen magnum decompression (FMD) for Chiari I malformation (CM-I) is rare; its natural history and pathophysiology are poorly understood. OBJECTIVE:To describe a series of patients who developed hydrocephalus following FMD for CM-I, provide possible explanations of this phenomenon, and outline treatment options. METHODS:Out of patients undergoing FMD for CM-I from 6 different tertiary centers, we evaluated patients presenting with new-onset hydrocephalus following FMD. The retrospectively collected data included demographics, clinical, and radiological findings of the CM-I and hydrocephalus patients. Time from FMD and hydrocephalus onset, treatment, and surgical techniques were assessed. RESULTS:Of 549 patients who underwent FMD for CM-I, 28 (5.1%) subsequently developed hydrocephalus (18 females, 10 males), with a mean age of 11.7 ± 11.9 yr (range 6 mo to 52 yr). Hydrocephalus occurred on average 2.2 ± 2.6 mo after FMD (range 1 wk to 8 mo). Four patients did not have a violation of the arachnoid during the FMD surgery. Main presenting symptoms of hydrocephalus were headaches (17, 41%), vomiting (10, 24.4%), and cerebrospinal fluid (CSF) leak or pseudomeningocele (7, 17%).Overall, 23 patients (82.1%) underwent CSF shunting, 1 patient (3.5%) had an endoscopic third ventriculostomy, 3 patients (10.7%) temporary CSF diversion only, and 1 patient (3.5%) was treated with acetazolamide. CONCLUSION/CONCLUSIONS:Hydrocephalus following FMD for CM-I is uncommon, but important. Based on our series and literature review, its incidence is about 5% to 7% and most likely will require further surgery. Shunting appears to be the favored treatment option.

PURPOSE/OBJECTIVE:All treatments for childhood craniopharyngioma are associated with complications that potentially affect quality of life. This study was designed to investigate the impact of gross total resection on long-term quality of life and sexual functioning in adulthood. METHODS:Adults treated with primary gross total resection for childhood craniopharyngioma and ≥ 10 years of follow-up were included in this retrospective cohort study. The Short Form 36 Health Survey Questionnaire Version 2 (SF-36v2), Medical Outcomes Study (MOS) sexual functioning survey, and a sociodemographic/health questionnaire were administered. RESULTS:). Preoperative hypothalamic involvement correlated with a significantly higher BMI, although the proportion of participants with class 3 obesity (BMI ≥ 40) did not differ significantly from that of the general population (9% and 7%, respectively). CONCLUSIONS:Young adults with gross total resection of childhood craniopharyngioma report similar quality of life and sexual functioning compared to the general population, but appear to be less sexually active. Hypothalamic involvement on preoperative imaging was associated with a higher BMI in long-term follow-up.

BACKGROUND:Ventriculoatrial shunts can be afflicted with distal malfunctions due to thrombus formation at the distal tip. Distal tip thrombus formation may occur more commonly in oncologic patients who are predisposed to hypercoagulability. CASE DESCRIPTION/METHODS:A patient who had a ventriculo-atrial shunt placed for leptomeningeal carcinomatosis presented with headaches and confusion and was found to have a partial distal shunt obstruction. Intra-reservoir administration of alteplase resulted in resolution of her symptoms. Nuclear medicine shunt patency test demonstrated restoration of distal flow. CONCLUSIONS:Intra-reservoir administration of alteplase can be a useful non-operative treatment strategy for ventriculo-atrial shunt malfunction. This strategy may be particularly useful in cases with higher peri-operative risk, such as patients with advanced metastatic cancer.

CONTEXT/BACKGROUND:X-linked acrogigantism (X-LAG), a condition of infant-onset acrogigantism marked by elevated GH, IGF-1, and prolactin (PRL), is extremely rare. Thirty-three cases, including three kindreds, have been reported. These patients have pituitary adenomas that are thought to be mixed lactotrophs and somatotrophs. CASE DESCRIPTION/METHODS:The patient's mother, diagnosed with acrogigantism at 21 months, underwent pituitary tumor excision at 24 months. For over 30 years, stable PRL, GH, and IGF-1 concentrations and serial imaging studies indicated no tumor recurrence. During pre-conception planning, X-LAG was diagnosed: single-nucleotide polymorphism (SNP) microarray showed chromosome Xq26.3 microduplication. After conception, SNP microarray on a chorionic villus sample showed the same microduplication in the fetus, confirming familial X-LAG. The infant grew rapidly with rising PRL, GH, and IGF-1 concentrations and an enlarging suprasellar pituitary mass, despite treatment with bromocriptine. At 15 months, he underwent tumor resection. The pituitary adenoma resembled the mother's pituitary adenoma, with tumor cells arranged in trabeculae and glandular structures. In both cases, many tumor cells expressed PRL, GH, and PIT1. Furthermore, the tumor expressed other lineage-specific transcription factors, as well as SOX2 and OCT4, demonstrating the multipotentiality of X-LAG tumors. Both showed an elevated Ki-67 proliferation index-5.6% (mother) and 8.5% (infant)-the highest reported in X-LAG. CONCLUSIONS:This is the first prenatally diagnosed case of X-LAG. Clinical follow-up and biochemical evaluation have provided insight into the natural history of this disease. Expression of stem cell markers and several cell lineage-specific transcription factors suggests that these tumors are multipotential.

OBJECTIVEThe authors describe the demographics and clinical characteristics of the first 517 patients enrolled in the Adult Hydrocephalus Clinical Research Network (AHCRN) during its first 2 years.METHODSAdults ≥ 18 years were nonconsecutively enrolled in a registry at 6 centers. Four categories of adult hydrocephalus were defined: transition (treated before age 18 years), unrecognized congenital (congenital pattern, not treated before age 18 years), acquired (secondary to known risk factors, treated or untreated), and suspected idiopathic normal pressure hydrocephalus (iNPH) (≥ age 65 years, not previously treated). Data include etiology, symptoms, examination findings, neuropsychology screening, comorbidities, treatment, complications, and outcomes. Standard evaluations were administered to all patients by trained examiners, including the Montreal Cognitive Assessment, the Symbol Digit Modalities Test, the Beck Depression Inventory-II, the Overactive Bladder Questionnaire Short Form symptom bother, the 10-Meter Walk Test, the Boon iNPH gait scale, the Lawton Activities of Daily Living/Instrumental Activities of Daily Living (ADL/IADL) questionnaire, the iNPH grading scale, and the modified Rankin Scale.RESULTSOverall, 517 individuals were enrolled. Age ranged from 18.1 to 90.7 years, with patients in the transition group (32.7 ± 10.0 years) being the youngest and those in the suspected iNPH group (76.5 ± 5.2 years) being the oldest. The proportion of patients in each group was as follows: 16.6% transition, 26.5% unrecognized congenital, 18.2% acquired, and 38.7% suspected iNPH. Excluding the 86 patients in the transition group, who all had received treatment, 79.4% of adults in the remaining 3 groups had not been treated at the time of enrollment. Patients in the suspected iNPH group had the poorest performance in cognitive evaluations, and those in the unrecognized congenital group had the best performance. The same pattern was seen in the Lawton ADL/IADL scores. Gait velocity was lowest in patients in the suspected iNPH group. Categories that had the most comorbidities (suspected iNPH) or etiologies of hydrocephalus that directly cause neurological injury (transition, acquired) had greater degrees of impairment compared to unrecognized congenital, which had the fewest comorbidities or etiologies associated with neurological injury.CONCLUSIONSThe clinical spectrum of hydrocephalus in adults comprises more than iNPH or acquired hydrocephalus. Only 39% of patients had suspected iNPH, whereas 43% had childhood onset (i.e., those in the transition and unrecognized congenital groups). The severity of symptoms and impairment was worsened when the etiology of the hydrocephalus or complications of treatment caused additional neurological injury or when multiple comorbidities were present. However, more than half of patients in the transition, unrecognized congenital, and acquired hydrocephalus groups had minimal or no impairment. Excluding the transition group, nearly 80% of patients in the AHCRN registry were untreated at the time of enrollment. A future goal for the AHCRN is to determine whether patients with unrecognized congenital and acquired hydrocephalus need treatment and which patients in the suspected iNPH cohort actually have possible hydrocephalus and should undergo further diagnostic testing. Future prospective research is needed in the diagnosis, treatment, outcomes, quality of life, and macroeconomics of all categories of adult hydrocephalus.