Preemptive strategies and lessons learned from complications encountered with microvascular decompression for hemifacial spasm

OBJECTIVE

Microvascular decompression (MVD) is the only curative treatment modality for hemifacial spasm (HFS). Although generally considered to be safe, this surgical procedure is surrounded by many risks and possible complications. The authors present the spectrum of complications that they met in their case series, the possible causes, and the strategies recommended to minimize them.

METHODS

The authors reviewed a prospectively maintained database for MVDs performed from 2005 until 2021 and extracted relevant data including patient demographics, offending vessel(s), operative technique, outcome, and different complications. Descriptive statistics with uni- and multivariable analyses for the factors that may influence the seventh, eighth, and lower cranial nerves were performed.

RESULTS

Data from 420 patients were obtained. Three hundred seventeen of 344 patients (92.2%) with a minimum follow-up of 12 months had a favorable outcome. The mean follow-up (standard deviation) was 51.3 ± 38.7 months. Immediate complications reached 18.8% (79/420). Complications persisted in only 7.14% of patients (30/420) including persistent hearing deficits (5.95%) and residual facial palsy (0.95%). Temporary complications included CSF leakage (3.10%), lower cranial nerve deficits (3.57%), meningitis (0.71%), and brainstem ischemia (0.24%). One patient died because of herpes encephalitis. Statistical analyses showed that the immediate postoperative disappearance of spasms and male gender are correlated with postoperative facial palsy, whereas combined vessel compressions involving the vertebral artery (VA) and anterior inferior cerebellar artery can predict postoperative hearing deterioration. VA compressions could predict postoperative lower cranial nerve deficits.

CONCLUSIONS

MVD is safe and effective for treating HFS with a low rate of permanent morbidity. Proper patient positioning, sharp arachnoid dissection, and endoscopic visualization under facial and auditory neurophysiological monitoring are the key points to minimize the rate of complications in MVD for HFS.

Late Frontal Bone Reconstruction Using Three-dimensional Printed Models For Titanium Mesh Customization: A Case Series

BACKGROUND

The convex frontal bone is covered by thin skin rendering its reconstruction cosmetically challenging. Customized alloplastic implants provide better contouring than autologous bone, yet their high cost and availability limit their application. We assess customized titanium mesh implants pre-contoured using patient specific 3-D printed models for late frontal cranioplasty.

METHODS

We retrospectively analyzed the prospectively collected cases of unilateral frontal titanium mesh cranioplasty with 3-D printing assisted preplanning from 2017 to 2019. We used two 3-D printed patient specific skull models for preoperative planning: the mirrored normal model for implant contouring, and the defect model for edge trimming and fixation planning. The endoscope was used in four cases for percutaneous mesh fixation. We documented postoperative complications. We assessed the reconstruction symmetry clinically, and radiologically on postoperative computed tomography.

RESULTS

15 patients were included. The duration after previous surgery ranged from 8-24 months. Four patients developed complications that were managed conservatively. Favorable cosmetic outcomes were achieved in all patients.

CONCLUSIONS

Pre-contouring of titanium mesh implants using in-house 3-D printed models could optimize cosmetic and surgical outcomes in late frontal cranioplasty. Preoperative planning could permit minimal access surgery that could be aided by the endoscope in select cases.

Risk factors of congenital hydrocephalus: a case-control study in a lower-middle-income country (Egypt)

OBJECTIVE

Hydrocephalus is the most common brain disorder in children and is more common in low- and middle-income countries. Research output on hydrocephalus remains sparse and of lower quality in low- and middle-income countries compared with high-income countries. Most studies addressing hydrocephalus epidemiology are retrospective registry studies entailing their inherent limitations and biases. This study aimed to investigate child-related, parental, and socioeconomic risk factors of congenital hydrocephalus (CH) in a lower-middle-income country.

METHODS

An investigator-administered questionnaire was used to query parents of patients with CH and controls who visited the authors' institution from 2017 until 2021. Patients with secondary hydrocephalus and children older than 2 years of age at diagnosis were excluded. Uni- and multivariable logistic regression was performed to identify the factors affecting CH development.

RESULTS

Seven hundred forty-one respondents (312 cases and 429 controls) were included in this study. The authors showed that maternal diseases during pregnancy (OR 3.12, 95% CI 1.96-5.03), a lack of periconceptional folic acid intake (OR 1.92, 95% CI 1.32-2.81), being a housewife (OR 2.66, 95% CI 1.51-4.87), paternal illiteracy (OR 1.65, 95% CI 1.02-2.69), parental consanguinity (OR 3.67, 95% CI 2.40-5.69), a history of other CNS conditions in the family (OR 2.93, 95% CI 1.24-7.34), conceiving a child via assisted fertilization techniques (OR 3.93, 95% CI 1.57-10.52), and the presence of other congenital anomalies (OR 2.57, 95% CI 1.38-4.87) were associated with an independent higher odds of a child having CH. Conversely, maternal hypertension (OR 0.22, 95% CI 0.09-0.48), older maternal age at delivery (OR 0.93, 95% CI 0.89-0.97), and having more abortions (OR 0.80, 95% CI 0.67-0.95) were negatively correlated with CH.

CONCLUSIONS

Multiple parental, socioeconomic, and child-related factors were associated with higher odds for developing CH. These results can be utilized to guide parental counseling and management, and direct social education and prevention programs.

An eye on the future for defeating hydrocephalus, ciliary dyskinesia-related hydrocephalus: review article

Congenital hydrocephalus affects approximately one in 1000 newborn children and is fatal in approximately 50% of untreated cases. The currently known management protocols usually necessitate multiple interventions and long-term use of healthcare resources due to a relatively high incidence of complications, and many of them mostly provide a treatment of the effect rather than the cause of cerebrospinal fluid flow reduction or outflow obstruction. Future studies discussing etiology specific hydrocephalus alternative treatments are needed. We systematically reviewed the available literature on the effect of ciliary abnormality on congenital hydrocephalus pathogenesis, to open a discussion on the feasibility of factoring ciliary abnormality in future research on hydrocephalus treatment modalities. Although there are different forms of ciliopathies, we focused in this review on primary ciliary dyskinesia. There is growing evidence of association of other ciliary syndromes and hydrocephalus, such as the reduced generation of multiple motile cilia, which is distinct from primary ciliary dyskinesia. Data for this review were identified by searching PubMed using the search terms 'hydrocephalus,' 'Kartagener syndrome,' 'primary ciliary dyskinesia,' and 'immotile cilia syndrome.' Only articles published in English and reporting human patients were included. Seven studies met our inclusion criteria, reporting 12 cases of hydrocephalus associated with primary ciliary dyskinesia. The patients had variable clinical presentations, genetic backgrounds, and ciliary defects. The ependymal water propelling cilia differ in structure and function from the mucus propelling cilia, and there is a possibility of isolated non-syndromic ependymal ciliopathy causing only hydrocephalus with growing evidence in the literature for the association ependymal ciliary abnormality and hydrocephalus. Abdominal and thoracic situs in children with hydrocephalus can be evaluated, and secondary damage of ependymal cilia causing hydrocephalus in cases with generalized ciliary abnormality can be considered.

Soft tissue density within the foramen magnum, a predictor for surgical intervention in pediatric patients with Chiari malformation type I

OBJECTIVE

Chiari malformation type I (CMI) is diagnosed as herniation of the cerebellar tonsils by at least 5 mm below the foramen magnum. However, the degree of tonsillar herniation is a poor predictor of the need for decompression surgery. Exploration for an alternative morphological predictor for surgical intervention could provide greater insight into the development of an appropriate treatment plan for these patients. To investigate this issue, the authors calculated the soft tissue density within the foramen magnum as a measure of impaction of the cerebellar tonsils. Soft tissue density within the foramen magnum and degree of tonsillar herniation were then assessed for their correlation with the need for surgical intervention.

METHODS

The authors conducted a retrospective, longitudinal chart review of pediatric patients with CMI. Those who had undergone surgical intervention were considered symptomatic and those who had been treated conservatively, as asymptomatic. Soft tissue density was found by dividing the soft tissue occupancy of the foramen magnum (brainstem and cerebellar tonsils) by the total area of the bony foramen magnum. The predictive value of these two measurements for the need of surgery was determined.

RESULTS

Of the 465 patients seen for CMI at the authors' institution between July 1, 2011, and May 31, 2017, 80 underwent surgical intervention and 385 were asymptomatic. The average tissue density was significantly greater in the surgical group than in the asymptomatic group (83.3% and 78.6%, respectively, p < 0.0001). The average tonsillar descent for surgical patients was 10.8 mm compared to 9.8 mm for asymptomatic patients (p = 0.140). The point-biserial correlation coefficient was assessed, and soft tissue density was found to positively correlate with the need for surgical intervention (rpb = 0.199, p = 0.0001), whereas tonsillar herniation did not correlate with the need for surgery (rpb = 0.083, p = 0.115). Additionally, the degree of tonsillar herniation did not correlate with soft tissue density (r = 0.09), indicating that soft tissue density is an independent morphological parameter.

CONCLUSIONS

The study findings suggest that the need for surgical intervention in CMI patients is positively correlated with increasing soft tissue density within the foramen magnum, whereas the degree of tonsillar herniation did not show a correlation with the need for surgical intervention. Additionally, soft tissue density is a factor independent of the degree of tonsillar herniation. Further investigation of tissue density within the foramen magnum is needed in the hope of discovering a clinically applicable parameter that would indicate a need for surgical intervention in patients with CMI.

Visual changes after space flight: is it really caused by increased intracranial tension? A systematic review

INTRODUCTION

Spaceflight-Associated Neuro-ocular Syndrome (SANS) was linked to increased intracranial pressure (ICP) attributable to the combined effects of microgravity and environmental conditions encountered during spaceflight. Microgravity countermeasures as lower body negative pressure (LBNP) are potential interventions for SANS. Our aim is to provide a comprehensive qualitative analysis of literature contrasting simulation and spaceflight studies, focusing on the pathophysiology of SANS, and highlighting gaps in current knowledge.

EVIDENCE ACQUISITION

We systematically searched PubMed electronic database for English primary research published until February 2019 discussing intracranial changes in spaceflight or simulated microgravity, excluding animal and experimental studies. Two authors screened all the abstracts with a third author resolving disagreements. The full-text manuscripts were analyzed in pilot-tested tables.

EVIDENCE SYNTHESIS

Nineteen studies were reviewed; 13 simulation, and two out of six spaceflight studies were prospective. ICP changes were investigated in 11 simulation studies, where eight demonstrated a significant increase in ICP after variable periods of head-down tilt. three showed a significant increase in intraocular pressure (IOP) in conjunction with ICP elevation. With increasing ambient CO<inf>2</inf>: one showed an increase in IOP without further increase in ICP, while another showed a slight further decrease in ICP. LBNP demonstrated no significant effect on ICP in one and a decrease thereof in another study. After spaceflight, increased ICP on lumbar puncture was demonstrated in five studies.

CONCLUSIONS

Exposure to microgravity increases ICP possibly precipitating ocular changes. Whether other factors come into play is the subject of investigation. Further randomized studies and methods of direct ICP measurement during spaceflight are needed.

Incidence of and Causes for Ventriculoperitoneal Shunt Failure in Children Younger Than 2 Years: A Systematic Review

Objectives Ventriculoperitoneal (VP) shunting is commonly used to treat pediatric hydrocephalus, but failure rates are high. VP shunt failure in children is mostly caused by infection and/or proximal/distal shunt obstruction. However, to our knowledge, no previous reviews have discussed this topic using only clinical studies when age-related data could be obtained. This systematic review aimed at reevaluating what is already known as the most common causes of shunt failure and to determine the incidence and causes of VP shunt failure during the first 2 years of life as a step to establish solid evidence-based guidelines to avoid VP shunt failure in infants.

Methods We performed a search using the search terms “Cerebrospinal Fluid Shunts” (Medical Subject Headings [MeSH]) AND failure [All Fields] AND (“humans” [MeSH] AND English [lang] AND “infant” [MeSH]). Only articles that specifically discussed VP shunt complications in children < 2 years were included.

Results We found that the most common causes of VP shunt failure in children < 2 years were shunt obstruction and infection, both observed in a range.

Conclusion VP shunt failure is very common in infants, mostly resulting from obstruction and infection. Future studies should focus on methods designed to avoid these complications or on alternative treatments for hydrocephalus.

Certainty and uncertainty in genetic counselling: a qualitative case study

This study examines the communication that occurs during routine genetic counselling sessions. It involves the qualitative analysis of nine consultations with one member of a clinical genetics team. The consultations were characterised by a contrast between the sense of certainty apparent in how the clinicians talked about the power and promise of the new genetics and the uncertainty communicated regarding the actual information produced by genetic tests and their limitations in solving people's problems. There was also a contrast between how the clinician seemed to control the format and agenda of the consultation and the apparently uncontrollable personal and social implications of the topics discussed. We speculate that this may be explained in terms of the clinician giving some order and certainty in an area of inherent uncertainty, and where great promises are as yet unrealised.