Telemetric Intracranial Pressure Monitoring in Syndromic Craniosynostosis

Multisuture and syndromic craniosynostoses: Simplifying the complex

Most complex craniosynostoses are managed the same way as syndromic craniosynostoses (SCs), as these patients often experience similar problems regarding cognition and increased intracranial pressure (ICP). The evaluation and treatment plan for craniosynostoses is complex, and this, additionally, is complicated by the age at presentation. In this article, the authors review the complexity of SCs in the presentation and management. An algorithm is necessary for such multifaceted and multidimensional pathology as craniosynostoses. In most algorithms, posterior calvarial distraction is a consistent early option for complex craniosynostoses presenting early with raised ICP. Addressing the airway early is critical when significant airway issues are there. All other surgical interventions are tailored on the basis of presentation and age.

Telemetric Intracranial Pressure Monitoring: A Systematic Review

Telemetric intracranial pressure (ICP) monitoring is a new method of measuring ICP which eliminates some of the shortcomings of previous methods. However, there are limited data on specific characteristics, including the advantages and disadvantages of this method. The main aim of this study was to demonstrate the indications, benefits, and complications of telemetric ICP monitoring. PubMed, MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials were searched for relevant studies without language or date restriction in May 2019. Human studies in which telemetric ICP monitoring was the main subject of the study were included. Our initial search resulted in 1650 articles from which 50 studies were included. There were no randomized controlled trials. The majority of the studies were case reports or case series (68%). The most common aim of studies was testing of the device (52%), and monitoring the disease progression or recovery (46%). The most common indications for telemetric ICP monitoring in these studies were testing cerebrospinal fluid shunt function (46%), ICP control after the procedure (36%), and diagnosing intracranial hypertension (22%) and hydrocephalus (12%). In total, 1423 brain disease patients had been monitored in studies. The possibility of long-term ICP monitoring as the main benefit was reported in 38 (76%) studies. The associated complication rate was 7.1%. Despite the increasing application of telemetric monitoring devices, studies to evaluate specific characteristics of this method have been infrequent and inadequate. Future research using a higher level of scientific methods is needed to evaluate advantage and disadvantages.

Telemetric intracranial pressure monitoring in children

PURPOSE

Repeated intracranial pressure (ICP) measurements are essential in treatment of patients with complex cerebrospinal fluid (CSF) disorders. These patients often have a long surgical history with numerous invasive lumbar or intracranial pressure monitoring sessions and/or ventriculoperitoneal (VP) shunt revisions. Telemetric ICP monitoring might be an advantageous tool in treatment of these patients. In this paper, we evaluate our experience with this technology in paediatric patients.

METHODS

During a 4-year period, we implanted telemetric ICP sensors (Raumedic NEUROVENT-P-tel) in 20 paediatric patients to minimise the number of future invasive procedures. Patients were diagnosed with hydrocephalus, idiopathic intracranial hypertension (IIH) or an arachnoid cyst. Most patients (85%) had a VP shunt at the time of sensor implantation.

RESULTS

In total, 32 sensors were inserted in the 20 patients; the cause of re-implantation was technical malfunction of the implant. One sensor was explanted due to wound infection and one due to skin erosion. We experienced no complications directly related to the implantation/explantation procedures. A total of 149 recording sessions were conducted, including 68 home monitoring sessions. The median implantation period was 523 days with a median duration of clinical use at 202 days. The most likely consequence of a recording session was non-surgical treatment alteration (shunt valve adjustment or acetazolamide dose adjustment).

CONCLUSION

Telemetric ICP monitoring in children is safe and potentially decreases the number of invasive procedures. We find that telemetric ICP monitoring aids the clinical management of patients with complex CSF disorders and improves everyday life for both patient and parents. It allows continuous ICP measurement in the patient's home and thereby potentially reducing hospitalisations, leading to significant cost savings.

The role of ICP overnight monitoring (ONM) in children with suspected craniostenosis

PURPOSE

Secondary craniostenosis is a relevant problem pediatric neurosurgeons are confronted with and poses challenges regarding reliable diagnosis of raised ICP, especially in case of absent or questionable papilledema. How to identify children with elevated ICP is still controversial and diagnostics vary. We report on our experience with computerized ICP ONM in relation to imaging derived parameters.

METHODS

Thirty-four children with primary or secondary craniostenosis and clinical suspicion of raised ICP were investigated. We compared clinical signs, history, and radiographic assessment with the results of computerized ICP ONM. Differences were significant at a p < 0.05.

RESULTS

Baseline ICP was significantly higher in patients with combined suture synostosis, who also had a higher rate of questionable papilledema. Children with narrowed external CSF spaces in MRI had significantly higher ICP levels during REM sleep. Mean RAP was significantly elevated in patients with multi-suture synostosis, indicating poor intracranial compensatory reserve. Syndromal craniostenosis was associated with elevated ICP, RAP was significantly lower, and skull X-rays showed more impressions (copper beaten skull). RAP increased with more severe impressions only to decline in most severe abnormalities, indicating exhaustion of cerebrovascular reserve at an upper ICP breakpoint of 23.9 mmHg. Headaches correlated to lower ICP and were not associated with more severe X-ray abnormalities.

CONCLUSION

Narrowed external CSF spaces in MRI seem to be associated to elevated ICP. Skull X-rays can help to identify patients at risk for chronically elevated ICP. Severe X-ray changes correlate with exhausted cerebrovascular reserve as indicated by RAP decline. Only ICP monitoring clearly identifies raised ICP and low brain compliance. Thus, in cases with ambiguous imaging, ONM constitutes an effective tool to acquire objective data for identification of surgical candidates.

Conservative and operative management of iatrogenic craniocerebral disproportion-a case-based review

INTRODUCTION

Craniocerebral disproportion (CCD) can occur as a sequela after shunting in early infancy. It can be understood as a disorder closely related to slit ventricle syndrome and chronic overdrainage syndrome. Here, we present two exemplary cases and summarize the pathophysiological, diagnostic, and therapeutic approaches to CCD.

CLINICAL PRESENTATION

Two premature babies underwent shunting for posthemorrhagic hydrocephalus and presented in later childhood with recurrent episodes of symptomatic raised intracranial pressure (ICP) at 2 and 8 years of age, respectively.

DIAGNOSIS AND MANAGEMENT

Both patients had unchanged ventricular size on cranial imaging and fulfilled the clinical diagnostic criteria of CCD. After confirming shunt patency, ICP monitoring was performed to diagnose intermittent intracranial hypertension. Different treatment pathways were pursued: While readjustment of a programmable shunt valve was sufficient to alleviate the raised ICP in the first case, a cranial expansion surgery was necessary in the second case.

OUTCOME AND CONCLUSIONS

Both children were treated successfully after thorough assessment and careful choice of treatment approaches. This review provides detailed insight into CCD and highlights the importance of individual and critical decision-making in these complex patients.

Incomplete reossification after craniosynostosis surgery-incidence and analysis of risk factors: a clinical-radiological assessment study

OBJECTIVE One of the principles of the surgical treatment of craniosynostosis includes the release of fused bone plates to prevent recurrence. Such bone defects require a reossification process after surgery to prevent a cosmetic problem or brain vulnerability to damage. The objective of this study is to describe and analyze the radiological and clinical evolution of bone defects after craniosynostosis. METHODS From January 2005 to May 2016, 248 infants underwent surgical correction of craniosynostosis at HUiP La Fe Valencia; the authors analyzed data from 216 of these cases that met the inclusion criteria for this study. Various surgical techniques were used according to the age of the patient and severity of the case, including endoscopic-assisted suturectomy, open suturectomy, fronto-orbital advancement, and cranial vault remodeling. Clinical follow-up and radiological quantitative measurements in 2 periods-12-24 months and 2 years after surgery-were analyzed; 94 patients had a postoperative CT scan and were included in the radiological analysis. RESULTS At the end of the follow-up period, 92 of 216 patients (42.59%) showed complete closure of the bone defect, 112 patients (51.85%) had minor bone defects, and 12 patients (5.56%) had significant bone defects that required surgical intervention. In the multivariate analysis, age at first surgery was not significantly associated with incomplete reossification (p = 0.15), nor was surgical site infection (p = 0.75). Multivariate analysis identified area of cranial defect greater than 5 cm² in the first CT scan as predictive of incomplete reossification (p = 0.04). The mean area of cranial defect in the first CT scan (12-24 months after surgery) was 3.69 cm² in patients treated with open surgery and 7.13 cm² in those treated with endoscopic-assisted procedures; in the multivariate analysis, type of procedure was not related to incomplete reossification (p = 0.46). The positive predictive value of palpation as evaluation of bone cranial defects was 50% for significant defects and 71% for minor defects. CONCLUSIONS The incidence of cranial defects due to incomplete reossification requiring cranioplasty was 5.56% in our series. Defects greater than 5 cm² in the first postoperative CT scan showed a positive association with incomplete reossification. Patients treated with endoscope-assisted procedures had larger defects in the initial follow-up, but the final incidence of cranial defects was not significantly different in the endoscope-assisted surgery group from that in the open surgery group.

Morphometric Analysis of the Posterior Cranial Fossa in Syndromic and Nonsyndromic Craniosynostosis

Posterior cranial fossa (PCF) anatomy can be abnormal in craniosynostosis, and hindbrain herniation may occur. This study analyzed PCF anatomy in single suture and complex craniosynostosis.Children with craniosynostosis and age-matched controls were identified. Cephalic index (CI) for cranial vault and PCF as well as tentorial (TA) and occipital angles (OA) were measured on preoperative imaging.Children with syndromic (N = 6), bicoronal (N = 4), sagittal (N = 12), and metopic synostosis (N = 4) as well as controls (N = 10) were enrolled. Mean CI for cranial vault was 0.89, 0.93, 0.65, 0.74, and 0.78, respectively. Corresponding CI for PCF was 0.81, 0.93, 0.62, 0.74, and 0.78. Mean TA and OA were 45.4° and 96.6° in syndromic, 39.7° and 87.0° in bicoronal, 34.0 and 75.0° in sagittal, 39.7° and 87.0° in metopic synostosis, and 42.9° and 88.3° in controls.While CI, TA, and OA in metopic synostosis were similar to controls, abnormalities were found in syndromic, bicoronal, and sagittal synostosis. Syndromic and bicoronal craniosynostosis patients had a higher CI for both cranial vault and PFC as well as larger TA and OA, indicating a brachycephalic skull with steep tentorium and narrow PCF. In sagittal synostosis, CI for cranial vault and PCF were lower and TA and OA smaller, reflecting scaphocephalic deformity also at PCF, with a flat tentorium. This study provides basic PCF morphometry in craniofacial conditions.