Central sleep apnea and Chiari 1 malformation in a pediatric patient with Klippel-Feil syndrome

Cardiovascular Findings in Klippel-Feil Syndrome: A Systematic Review

Klippel-Feil syndrome (KFS) is a congenital disease defined by an abnormal fusion between cervical vertebrae. Due to the rarity of the disorder, its prevalence, along with its pathogenesis and associated conditions, remains to be clearly defined. The aim of this review is to summarize the findings of all case reports of KFS in PubMed over the last 10 years that describe cardiovascular disease, defects, or abnormalities. A total of 43 articles containing 46 reports were included from the 157 case reports considered. Cases were reviewed for commonality in biological sex and vertebral fusion and level using the Samartzis classification system to determine what association, if any, exists with the cardiovascular findings analyzed. A total of 72% of cases reported one or more findings consistent with congenital heart disease. Using the Samartzis classification system, type III KFS was the most common fusion profile overall in this subset of patients. The heterogeneity of disease manifestations makes the treatment and management of KFS case-dependent, though current guidelines highlight the importance of a multidisciplinary care team for pediatric patients. Our findings support this notion and provide evidence for the inclusion of a care provider who specializes in cardiovascular medicine in patients of all ages, as well as the consideration of additional diagnostic screening exams for cardiovascular abnormalities. Future studies into the embryological origin of KFS and a more robust search for a genetic marker are needed to better understand the development of the disease and its various associated conditions.

Intraoperative neuromonitoring in Chiari I malformation surgery: a systematic review and meta-analysis

Chiari Malformation Type I (CMI) is a prevalent neurosurgical condition characterized by the descent of cerebellar tonsils below the foramen magnum. Surgery, aimed at reducing symptomatology and syrinx size, presents risks, making intraoperative neuromonitoring (IONM) a potentially vital tool. Despite its widespread use in cervical spine surgery, the utility of IONM in CMI surgery remains controversial, with concerns over increased operative time, cost, restricted anesthetic techniques and tongue lacerations. This systematic review and meta-analysis followed the Cochrane Group standards and PRISMA framework. It encompassed an extensive search through PubMed, Embase, and Web of Science up to December 2023, focusing on clinical and surgical outcomes of IONM in CMI surgery. Primary outcomes included the use of various IONM techniques, complication rates, clinical improvement, reoperation, and mortality. The review, registered at PROSPERO (CRD42024498996), included both prospective and retrospective studies, with rigorous selection and data extraction processes. Statistical analysis was conducted using R software. The review included 16 studies, comprising 1358 patients. It revealed that IONM techniques predominantly involved somatosensory evoked potentials (SSEPs), followed by motor evoked potentials (MEPs) and Brainstem auditory evoked potentials (BAEPs). The estimated risk of complications with IONM was 6% (95% CI: 2-11%; I2 = 89%), lower than previously reported rates without IONM. Notably, the clinical improvement rate post-surgery was high at 99% (95% CI: 98-100%; I2 = 56%). The analysis also showed lower reoperation rates in surgeries with IONM compared to those without. Interestingly, no mortality was observed in the included studies. This systematic review and meta-analysis indicate that intraoperative neuromonitoring in Chiari I malformation surgery is associated with favorable clinical outcomes, including lower complication and reoperation rates, and high rates of clinical improvement.

A Comprehensive Approach to the Diagnosis and Management of Klippel Feil Syndrome

Klippel-Feil Syndrome (KFS) is a rare genetic disorder characterized by the abnormal development of the cervical spine, leading to the fusion of two or more cervical vertebrae. The syndrome presents diverse symptoms, including limited neck movement, chronic pain, and neurological manifestations such as limb numbness or weakness. The severity of KFS can vary significantly, and treatment primarily focuses on symptom management and preventing complications such as scoliosis or spinal cord compression. Surgical interventions are often necessary for patients with complex forms of the syndrome. Interestingly, Chiari 1 malformation, a cranial anomaly affecting the brainstem, can coincide anatomically with KFS. In this case report, we present the case of a 9-year-old patient who sought medical attention due to persistent, unchanging neck pain. The patient's medical history was notable for developmental delays and cervical restraint observed during physical examination. Magnetic resonance imaging (MRI) findings revealed hydrocephalus and brainstem descent, indicating the presence of Chiari 1 malformation. Comprehensive MRI and CT scans were performed, and a management plan was formulated, primarily involving cranial surgery and physiotherapy. Implementation of the treatment approach resulted in significant improvement in the patient's symptoms. This case highlights the significance of considering Chiari 1 malformation as a potential comorbidity in patients diagnosed with KFS who present with persistent neck pain. Early detection and appropriate management of both conditions are crucial for achieving favorable outcomes and enhancing the quality of life for affected individuals. Understanding the complex interplay between KFS and Chiari 1 malformation is essential for providing comprehensive care and tailored treatment strategies. Further research is warranted to elucidate the underlying mechanisms linking these two conditions and to explore optimal management approaches for patients with dual pathology. By reporting this case, we contribute to the existing literature and increase awareness among healthcare professionals regarding the potential coexistence of KFS and Chiari 1 malformation. Continued efforts in identifying associated anomalies and optimizing therapeutic interventions will aid in improving patient outcomes and ensuring optimal care for individuals affected by these conditions.

Chiari 1 malformation and exome sequencing in 51 trios: the emerging role of rare missense variants in chromatin-remodeling genes

Type 1 Chiari malformation (C1M) is characterized by cerebellar tonsillar herniation of 3–5 mm or more, the frequency of which is presumably much higher than one in 1000 births, as previously believed. Its etiology remains undefined, although a genetic basis is strongly supported by C1M presence in numerous genetic syndromes associated with different genes. Whole-exome sequencing (WES) in 51 between isolated and syndromic pediatric cases and their relatives was performed after confirmation of the defect by brain magnetic resonance image (MRI). Moreover, in all the cases showing an inherited candidate variant, brain MRI was performed in both parents and not only in the carrier one to investigate whether the defect segregated with the variant. More than half of the variants were Missense and belonged to the same chromatin-remodeling genes whose protein truncation variants are associated with severe neurodevelopmental syndromes. In the remaining cases, variants have been detected in genes with a role in cranial bone sutures, microcephaly, neural tube defects, and RASopathy. This study shows that the frequency of C1M is widely underestimated, in fact many of the variants, in particular those in the chromatin-remodeling genes, were inherited from a parent with C1M, either asymptomatic or with mild symptoms. In addition, C1M is a Mendelian trait, in most cases inherited as dominant. Finally, we demonstrate that modifications of the genes that regulate chromatin architecture can cause localized anatomical alterations, with symptoms of varying degrees.