Minimally Invasive Techniques in the Surgical Management of Traumatic Pediatric Thoracolumbar Fractures

BACKGROUND

Thoracolumbar (TL) fractures are uncommon in children. While surgical treatment is recommended for unstable TL fractures, there is no consensus on appropriate surgical treatment. We present a case series of pediatric patients with traumatic TL fractures treated with minimally invasive techniques. We discuss our early experience and technical challenges with navigation and robotic-assisted fixation.

METHODS

A retrospective review of a prospectively maintained trauma database from February 2018 to February 2023 of all pediatric patients (<18 years old) undergoing percutaneous fixation for unstable TL fractures was performed. Minimally invasive techniques included fluoroscopy and/or navigation-guided or robotic-assisted surgery. Clinical course, radiographic findings, and technical challenges were reviewed.

RESULTS

A cohort of 12 patients (age range, 4-17 years) with 6 (50%) Chance fractures, 2 (16%) pars fractures, 2 (16%) pedicle fracture, 1 (8%) burst fracture, and 1 (8%) other fracture were identified. Nine patients had fractures involving the lumbar spine, and the remaining 3 had thoracic fractures. In all cases, percutaneous pedicle screws were placed above and below the fracture with the use of neuronavigation or robotic-assisted navigation (n = 2). Blood loss was <30 mL for single-level fractures and instrumented fusion. Two patients had hardware-related complications. At follow-up (mean 9.67 months after surgery), patients were doing well clinically, and most imaging showed stable alignment.

CONCLUSIONS

Our early experience shows that short segment instrumentation through a minimally invasive approach is a safe and effective surgical option for young pediatric patients with good clinical outcomes and favorable radiographic postoperative finding.

Recovering fetal signals transabdominally through interferometric near-infrared spectroscopy (iNIRS)

Noninvasive transabdominal fetal pulse oximetry can provide clinicians critical assessment of fetal health and potentially contribute to improved management of childbirth. Conventional pulse oximetry through continuous wave (CW) light has challenges measuring the signals from deep tissue and separating the weak fetal signal from the strong maternal signal. Here, we propose a new approach for transabdominal fetal pulse oximetry through interferometric near-infrared spectroscopy (iNIRS). This approach provides pathlengths of photons traversing the tissue, which facilitates the extraction of fetal signals by rejecting the very strong maternal signal from superficial layers. We use a multimode fiber combined with a mode-field converter at the detection arm to boost the signal of iNIRS. Together, we can detect signals from deep tissue (>∼1.6 cm in sheep abdomen and in human forearm) at merely 1.1 cm distance from the source. Using a pregnant sheep model, we experimentally measured and extracted the fetal heartbeat signals originating from deep tissue. This validated a key step towards transabdominal fetal pulse oximetry through iNIRS and set a foundation for further development of this method to measure the fetal oxygen saturation.

Pressure control cam displacement in the Codman-Hakim programmable valve after a 3T MRI: Case report and review of the literature

Pressure control cam dislocation is a rare finding in patients with a programmable shunt valve that should be considered when evaluating patients with signs and symptoms of shunt malfunction. The objective of this paper is to review the mechanism, clinical presentation, and radiographic findings associated with pressure control cam (PCC) dislocation, in addition to presenting a novel case to add to the scarce literature on this topic. A systematic review of the literature were performed using PubMed, Embase, and Cochrane from database inception. PCC dislocation is exceedingly rare and can present with no symptoms, positional headache, neck pain, nausea, or vomiting. Skull x-ray findings demonstrate a clear black "X" at the distal end of the valve, due to the PCC disarticulation from atop the base plate of the plastic valve housing. Intraoperatively, a "Y"-shaped crack atop the plastic valve housing may be present and the PCC may be fully separated from the shunt or found at the distal end of the plastic valve housing. Prior reports of dislocation of the PCC have occurred 7-9 years after implantation, with inciting events including direct trauma, programmable valve adjustment, and utilization 3-Tesla magnetic resonance image scan.

The Molecular Mechanisms Through Which Placental Mesenchymal Stem Cell-Derived Extracellular Vesicles Promote Myelin Regeneration

Multiple sclerosis (MS) is a debilitating degenerative disease characterized by an immunological attack on the myelin sheath leading to demyelination and axon degeneration. Mesenchymal stem/stromal cells (MSCs) and secreted extracellular vesicles (EVs) have become attractive targets as therapies to treat neurodegenerative diseases such as MS due to their potent immunomodulatory and regenerative properties. The placenta is a unique source of MSCs (PMSCs), demonstrates "fetomaternal" tolerance during pregnancy, and serves as a novel source of MSCs for the treatment of neurodegenerative diseases. PMSCs and PMSC-EVs have been shown to promote remyelination in animal models of MS, however, the molecular mechanisms by which modulation of autoimmunity and promotion of myelination occurs have not been well elucidated. The current review will address the molecular mechanisms by which PMSC-EVs can promote remyelination in MS.

Cost-effectiveness of a Bone-anchored Annular Closure Device Versus Conventional Lumbar Discectomy in Treating Lumbar Disc Herniations

STUDY DESIGN

Cost-utility analysis of an annular closure device (ACD) based on data from a prospective, multicenter randomized controlled trial (RCT) OBJECTIVE.: The aim of this study was to determine the cost-effectiveness of a novel ACD in a patient population at high risk for recurrent herniation following discectomy.

SUMMARY OF BACKGROUND DATA

Lumbar disc herniation patients with annular defect widths ≥6 mm are at high risk for recurrent herniation following limited discectomy. Recurrent herniation is associated with worse clinical outcomes and greater healthcare costs. A novel ACD may reduce the incidence of recurrent herniation and the associated burdens.

METHODS

A decision analytical modeling approach with a Markov method was used to evaluate the cost-effectiveness of the ACD versus conventional discectomy. Health states were created by projecting visual analogue scale (VAS) onto Oswestry Disability Index (ODI). Direct costs were calculated based on Humana and Medicare 2014 claims to represent private and public payer data, respectively. Indirect costs were calculated for lost work days using 2016 US average annual wages. The incremental cost-effectiveness ratio (ICER) in dollars per quality-adjusted life year (QALY) was compared to willingness-to-pay thresholds. Sensitivity analyses were also conducted.

RESULTS

Patients with the ACD had less symptomatic reherniations, reoperations, and complications and gained 0.0328 QALYs within the first 2 years. Total direct medical costs for the ACD group were similar to control. When productivity loss was considered, using the ACD became $2076 cheaper, per patient, than conventional discectomy. Based on direct costs alone, the ICER comparing ACD to control equaled $6030 per QALY. When indirect costs are included, the ICER became negative, which indicates that superior quality of life was attained at less cost.

CONCLUSION

For lumbar disc herniations patients with annular defects ≥6 mm, the ACD was, at 2 years, a highly cost-effective surgical modality compared to conventional lumbar discectomy.

LEVEL OF EVIDENCE

1.

Review of the Neural Oscillations Underlying Meditation

Objective: Meditation is one type of mental training that has been shown to produce many cognitive benefits. Meditation practice is associated with improvement in concentration and reduction of stress, depression, and anxiety symptoms. Furthermore, different forms of meditation training are now being used as interventions for a variety of psychological and somatic illnesses. These benefits are thought to occur as a result of neurophysiologic changes. The most commonly studied specific meditation practices are focused attention (FA), open-monitoring (OM), as well as transcendental meditation (TM), and loving-kindness (LK) meditation. In this review, we compare the neural oscillatory patterns during these forms of meditation.

Method: We performed a systematic review of neural oscillations during FA, OM, TM, and LK meditation practices, comparing meditators to meditation-naïve adults.

Results: FA, OM, TM, and LK meditation are associated with global increases in oscillatory activity in meditators compared to meditation-naïve adults, with larger changes occurring as the length of meditation training increases. While FA and OM are related to increases in anterior theta activity, only FA is associated with changes in posterior theta oscillations. Alpha activity increases in posterior brain regions during both FA and OM. In anterior regions, FA shows a bilateral increase in alpha power, while OM shows a decrease only in left-sided power. Gamma activity in these meditation practices is similar in frontal regions, but increases are variable in parietal and occipital regions.

Conclusions: The current literature suggests distinct differences in neural oscillatory activity among FA, OM, TM, and LK meditation practices. Further characterizing these oscillatory changes may better elucidate the cognitive and therapeutic effects of specific meditation practices, and potentially lead to the development of novel neuromodulation targets to take advantage of their benefits.

Treatment of cervical radiculopathy: A review of the evolution and economics

Background:

The surgical treatment of cervical radiculopathy has centered around anterior cervical discectomy and fusion (ACDF). Alternatively, the posterior cervical laminoforaminotomy/microdiscectomy (PCF/PCM), which results in comparable outcomes and is more cost-effective, has been underutilized.

Methods:

Here, we compared the direct/indirect costs, reoperation rates, and outcome for ACDF and PCF vs. PCM using PubMed, Medline, and Embase databases.

Results:

There were no significant differences between the re-operative rates of PCF/PCM (2% to 9.8%) versus ACDF (2% to 8%). Direct costs of ACDF were also significantly higher; the 1-year cost-utility analysis demonstrated that ACDF had $131,951/QALY while PCM had $79,856/QALY.

Conclusion:

PCF/PCM for radiculopathy are safe and more cost-effective vs. ACDF, and have similar clinical outcomes.

Identification and repair of intraoperative cerebrospinal fluid leaks in endonasal transsphenoidal pituitary surgery: surgical experience in a series of 1002 patients

OBJECTIVE Cerebrospinal fluid (CSF) rhinorrhea is among the most common complications following transsphenoidal surgery for sellar region lesions. The aim of this study was to review the authors' institutional experience in identifying, repairing, and treating CSF leaks associated with direct endonasal transsphenoidal operations. METHODS The authors performed a retrospective review of cases involving surgical treatment of pituitary adenomas and other sellar lesions at the University of Southern California between December 1995 and March 2016. Inclusion criteria included all pathology of the sellar region approached via a direct microscopic or endoscopic endonasal transsphenoidal approach. Demographics, pathology, intraoperative and postoperative CSF leak rates, and other complications were recorded and analyzed. A literature review of the incidence of CSF leaks associated with the direct endonasal transsphenoidal approach to pituitary lesions was conducted. RESULTS A total of 1002 patients met the inclusion criteria and their cases were subsequently analyzed. Preoperative diagnoses included pituitary adenomas in 855 cases (85.4%), Rathke's cleft cyst in 94 (9.4%), and other sellar lesions in 53 (5.2%). Lesions with a diameter ≥ 1 cm made up 49% of the series. Intraoperative repair of an identified CSF leak was performed in 375 cases (37.4%) using autologous fat, fascia, or both. An additional 92 patients (9.2%) underwent empirical sellar reconstruction without evidence of an intraoperative CSF leak. Postoperative CSF leaks developed in 26 patients (2.6%), including 13 (1.3% of the overall group) in whom no intraoperative leak was identified. Among the 26 patients who developed a postoperative CSF leak, 13 were noted to have intraoperative leak and underwent sellar repair while the remaining 13 did not have an intraoperative leak or sellar repair. No patients who underwent empirical sellar repair without an intraoperative leak developed a postoperative leak. Eight patients underwent additional surgery (0.8% reoperation rate) for CSF leak repair, and 18 were successfully treated with lumbar drainage or lumbar puncture alone. The incidence of postoperative CSF rhinorrhea in this series was compared with that in 11 other reported series that met inclusion criteria, with incidence rates ranging between 0.6% and 12.1%. CONCLUSIONS In this large series, half of the patients who developed postoperative CSF rhinorrhea had no evidence of intraoperative CSF leakage. Unidentified intraoperative CSF leaks and/or delayed development of CSF fistulas are equally important sources of postoperative CSF rhinorrhea as the lack of employing effective CSF leak repair methods. Empirical sellar reconstruction in the absence of an intraoperative CSF leak may be of benefit following resection of large tumors, especially if the arachnoid is thinned out and herniates into the sella.

Mycobacterium Genavense Granuloma Mimicking a Brain Tumor: A Case Report

Mycobacterium genavense (M. genavense) is a rare, non-tuberculous organism that commonly leads to gastrointestinal infections in immunocompromised patients. Only two cases of intracranial M. genavense infection have been reported to date. We describe a third case of M. genavense granuloma mimicking a right parietal intracranial mass, and review the literature on this exceedingly rare pathology.

Sellar and clival plasmacytomas: case series of 5 patients with systematic review of 65 published cases

PURPOSE

Parasellar plasmacytomas are rare tumors localized to the sellar region arising from plasma cells. Knowledge of clinical, imaging, surgical, and pathological characteristics is limited to single case reports.

METHODS

A retrospective analysis of five primary cases was conducted, followed by systematic review of English language articles using PubMed in accordance with PRISMA guidelines.

RESULTS

Five primary case patients include four men and one woman, ages 60-77, followed up to 3 years. A systematic review identified 65 additional patients, of whom 65% presented with cranial nerve palsies and 15% with hypopituitarism. Sixteen percent had history of known multiple myeloma (MM) while 37% were diagnosed concurrently with MM on presentation of parasellar plasmacytoma. Imaging showed median tumor size of 38 mm (range, 4-70 mm), with MRI intensity similar to that of other sellar masses. Surgical biopsy with immunohistochemical studies confirmed plasmacytoma diagnosis. Eighty-one percent underwent parasellar radiotherapy, and chemotherapy initiated in 59% of the 69 patients with MM. Overall survival rate was 74% at follow-up (median 12 months), with 18% having parasellar recurrences and 38% progressing to systemic MM after presentation of a solitary plasmacytoma (median 3 months).

CONCLUSIONS

Parasellar plasmacytomas are rare tumors that should be considered in the differential diagnosis for lesions involving the sella and arising from the clivus, especially when cranial nerve paresis is apparent, even in the absence of known MM. Although recurrence rates for parasellar plasmacytoma is low, patients should be monitored for progression to MM. Treatment depends on the presence of systemic disease at diagnosis.