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Open access

Adam J. Kundishora, Benjamin C. Reeves, Andres Moreno-De-Luca, Christopher S. Hong, Stephanie M. Robert, Aladine A. Elsamadicy, Dominick Tuason, and Michael L. DiLuna

BACKGROUND

Hirayama disease, a cervical myelopathy characterized most commonly by a self-limiting atrophic weakness of the upper extremities, is a rare entity, scarcely reported in the literature. Diagnosis is made by spinal magnetic resonance imaging (MRI), which typically shows loss of normal cervical lordosis, anterior displacement of the cord during flexion, and a large epidural cervical fat pad. Treatment options include observation or cervical immobilization by collar or surgical decompression and fusion.

OBSERVATIONS

Here, the authors report an unusual case of a Hirayama-like disease in a young White male athlete who presented with rapidly progressive paresthesia in all 4 extremities and no weakness. Imaging showed characteristic findings of Hirayama disease as well as worsened cervical kyphosis and spinal cord compression in cervical neck extension, which has not previously been reported. Two-level anterior cervical discectomy and fusion and posterior spinal fusion improved both cervical kyphosis on extension and symptoms.

LESSONS

Given the disease’s self-limiting nature, and a lack of current reporting, there remains no consensus on how to manage these patients. Such findings presented here demonstrate the potentially heterogeneous MRI findings that can be observed in Hirayama disease and emphasize the utility of aggressive surgical management in young, active patients whereby a cervical collar may not be tolerated.

Open access

Vishwathsen Karthikeyan, Sara C. Breitbart, Armaan K. Malhotra, Andrea Fung, Erin Short, Ann Schmitz, David E. Lebel, and George M. Ibrahim

BACKGROUND

Cervical spine injuries in neonates are rare and no guidelines are available to inform management. The most common etiology of neonatal cervical injury is birth-related trauma. Management strategies that are routine in older children and adults are not feasible due to the unique anatomy of neonates.

OBSERVATIONS

Here, the authors present 3 cases of neonatal cervical spinal injury due to confirmed or suspected birth trauma, 2 of whom presented immediately after birth, while the other was diagnosed at 7 weeks of age. One child presented with neurological deficits due to spinal cord injury, while another had an underlying predisposition to bony injury, infantile malignant osteopetrosis. The children were treated with a custom-designed and manufactured full-body external orthoses with good clinical and radiographic outcomes. A narrative literature review further supplements this case series and highlights risk factors and the spectrum of birth-related spinal injuries reported to date.

LESSONS

The current report highlights the importance of recognizing the rare occurrence of cervical spinal injury in newborns and provides pragmatic recommendations for management of these injuries. Custom orthoses provide an alternate option for neonates who cannot be fitted in halo vests and who would outgrow traditional casts.

Open access

Zach Pennington, Nolan J. Brown, Saif Quadri, Seyedamirhossein Pishva, Cathleen C. Kuo, and Martin H. Pham

BACKGROUND

Minimally invasive surgical techniques are changing the landscape in adult spinal deformity (ASD) surgery, enabling surgical correction to be achievable in increasingly medically complex patients. Spinal robotics are one technology that have helped facilitate this. Here the authors present an illustrative case of the utility of robotics planning workflow for minimally invasive correction of ASD.

OBSERVATIONS

A 60-year-old female presented with persistent and debilitating low back and leg pain limiting her function and quality of life. Standing scoliosis radiographs demonstrated adult degenerative scoliosis (ADS), with a lumbar scoliosis of 53°, a pelvic incidence–lumbar lordosis mismatch of 44°, and pelvic tilt of 39°. Robotics planning software was utilized for preoperative planning of the multiple rod and 4-point pelvic fixation in the posterior construct.

LESSONS

To the authors’ knowledge, this is the first report detailing the use of spinal robotics for complex 11-level minimally invasive correction of ADS. Although additional experiences adapting spinal robotics to complex spinal deformities are necessary, the present case represents a proof-of-concept demonstrating the feasibility of applying this technology to minimally invasive correction of ASD.

Open access

Christopher S. Hong, Neelan J. Marianayagam, Saul F. Morales-Valero, Tanyeri Barak, Joanna K. Tabor, Joseph O’Brien, Anita Huttner, Joachim Baehring, Murat Gunel, E. Zeynep Erson-Omay, Robert K. Fulbright, Charles C. Matouk, and Jennifer Moliterno

BACKGROUND

Intratumoral aneurysms in highly vascular brain tumors can complicate resection depending on their location and feasibility of proximal control. Seemingly unrelated neurological symptoms may be from vascular steal that can help alert the need for additional vascular imaging and augmenting surgical strategies.

OBSERVATIONS

A 29-year-old female presented with headaches and unilateral blurred vision, secondary to a large right frontal dural-based lesion with hypointense signal thought to represent calcifications. Given these latter findings and clinical suspicion for a vascular steal phenomenon to explain the blurred vision, computed tomography angiography was obtained, revealing a 4 × 2–mm intratumoral aneurysm. Diagnostic cerebral angiography confirmed this along with vascular steal by the tumor from the right ophthalmic artery. The patient underwent endovascular embolization of the intratumoral aneurysm, followed by open tumor resection in the same setting without complication, minimal blood loss, and improvement in her vision.

LESSONS

Understanding the blood supply of any tumor, but highly vascular ones in particular, and the relationship with normal vasculature is undeniably important in avoiding potentially dangerous situations and optimizing maximal safe resection. Recognition of highly vascular tumors should prompt thorough understanding of the vascular supply and relationship of intracranial vasculature with consideration of endovascular adjuncts when appropriate.

Restricted access

Zhenghao Li, Yijie Lai, Jun Li, Naying He, Dianyou Li, Fuhua Yan, Yuyao Zhang, Chencheng Zhang, Bomin Sun, and Hongjiang Wei

OBJECTIVE

Functional MRI (fMRI) has been used to investigate the therapeutic mechanisms underlying deep brain stimulation (DBS) for Parkinson’s disease (PD). However, the alterations in stimulation site–seeded functional connectivity induced by DBS at the internal globus pallidus (GPi) remain unclear. Furthermore, whether DBS-modulated functional connectivity is differentially affected within particular frequency bands remains unknown. The present study aimed to reveal the alterations in stimulation site–seeded functional connectivity induced by GPi-DBS and to examine whether there exists a frequency band effect in blood oxygen level–dependent (BOLD) signals related to DBS.

METHODS

Patients with PD receiving GPi-DBS (n = 28) were recruited for resting-state fMRI with DBS on and DBS off under a 1.5-T MR scanner. Age- and sex-matched healthy controls (n = 16) and DBS-naïve PD patients (n = 24) also received fMRI scanning. The alterations in stimulation site–seeded functional connectivity in the stimulation-on state versus stimulation-off state, as well as the relationship between alterations in connectivity and improvement in motor function induced by GPi-DBS, were examined. Furthermore, the modulatory effect of GPi-DBS on the BOLD signals within the 4 frequency subbands (slow-2 to slow-5) was investigated. Finally, the functional connectivity of the motor-related network, consisting of multiple cortical and subcortical regions, was also examined among the groups. In this study, p < 0.05 with Gaussian random field correction indicates statistical significance.

RESULTS

Functional connectivity seeding from the stimulation site (i.e., the volume of tissue activated [VTA]) increased in the cortical sensorimotor areas and decreased in the prefrontal regions with GPi-DBS. Alterations in connectivity between the VTA and the cortical motor areas were correlated with motor improvement by pallidal stimulation. The alterations in connectivity were dissociable between the frequency subbands in the occipital and cerebellar areas. The motor network analysis indicated decreased connectivity among most cortical and subcortical regions but increased connectivity between the motor thalamus and the cortical motor area in patients with GPi-DBS compared with those in DBS-naïve patients. The DBS-induced decrease in several cortical-subcortical connectivities within the slow-5 band correlated with motor improvement with GPi-DBS.

CONCLUSIONS

These findings indicate that the alterations in functional connectivity from the stimulation site to the cortical motor areas, as well as multiple connectivities among the motor-related network, were associated with the efficacy of GPi-DBS for PD. Furthermore, the changing pattern of functional connectivity within the 4 BOLD frequency subbands is partially dissociable.

Open access

Mate Turbucz, Jennifer Fayad, Agoston J. Pokorni, Peter P. Varga, Peter E. Eltes, and Aron Lazary

OBJECTIVE

Proximal junctional kyphosis (PJK) is a relatively common complication following long instrumented posterior spinal fusion. Although several risk factors have been identified in the literature, previous biomechanical studies suggest that one of the leading causes is the sudden change in mobility between the instrumented and noninstrumented segments. The current study aims to assess the biomechanical effect of 1 rigid and 2 semirigid fixation techniques (SFTs) on developing PJK.

METHODS

Four T7–L5 finite element (FE) models were developed: 1) intact spine; 2) 5.5-mm titanium rod from T8 to L5 (titanium rod fixation [TRF]); 3) multiple rods from T8 to T9 connected with titanium rod from T9 to L5 (multiple-rod fixation [MRF]); and 4) polyetheretherketone rod from T8 to T9 connected with titanium rod from T9 to L5 (PEEK rod fixation [PRF]). A modified multidirectional hybrid test protocol was used. First, a pure bending moment of 5 Nm was applied to measure the intervertebral rotation angles. Second, the TRF technique’s displacement from the first loading step was applied to the instrumented FE models to compare the pedicle screw stress values in the upper instrumented vertebra (UIV).

RESULTS

In the load-controlled step, at the upper instrumented segment, the intervertebral rotation values relative to TRF increased by 46.8% and 99.2% for flexion, by 43.2% and 87.7% for extension, by 90.1% and 137% for lateral bending, and by 407.1% and 585.2% for axial rotation, in the case of MRF and PRF, respectively. In the displacement-controlled step, maximum pedicle screw stress values at the UIV level were highest in the case of TRF (37.26 MPa, 42.13 MPa, 44.4 MPa, and 44.59 MPa for flexion, extension, lateral bending, and axial rotation, respectively). Compared to TRF, in the case of MRF and PRF, the screw stress values were reduced by 17.3% and 27.7% for flexion, by 26.6% and 36.7% for extension, by 6.8% and 34.3% for lateral bending, and by 49.1% and 59.8% for axial rotation, respectively.

CONCLUSIONS

FE analysis has shown that the SFTs increase the mobility at the upper instrumented segment and therefore provide a more gradual transition in motion between the instrumented and rostral noninstrumented segments of the spine. In addition, SFTs decrease the screw loads at the UIV level and hence could help reduce the risk for PJK. However, further investigations are recommended to evaluate the long-term clinical usefulness of these techniques.

Restricted access

Zehao Zhao, Chu-Chung Huang, Shiwen Yuan, Jie Zhang, Ching-Po Lin, Junfeng Lu, Hugues Duffau, and Jinsong Wu

OBJECTIVE

The objective was to identify the correspondence between the anterior terminations of the arcuate fasciculus (AF) and third branch of the superior longitudinal fasciculus (SLF-III) and the intraoperative direct cortical electrical stimulation (DCS)–induced speech arrest area.

METHODS

The authors retrospectively screened 75 glioma patients (group 1) who received intraoperative DCS mapping in the left dominant frontal cortex. To minimize the influence of tumors or edema, we subsequently selected 26 patients (group 2) with glioma or edema not affecting Broca’s area, the ventral precentral gyrus (vPCG), and the subcortical pathways to generate DCS functional maps and to construct the anterior terminations of AF and SLF-III with tractography. Next, a grid-by-grid pairwise comparison was performed between the fiber terminations and the DCS-induced speech arrest sites to calculate Cohen’s kappa coefficient (κ) in both groups 1 and 2. Finally, the authors also demonstrated the distribution of the AF/SLF-III anterior projection maps obtained in 192 healthy participants (group 3) and subsequently correlated these with the speech arrest sites in group 2 to examine their validity in predicting speech output area.

RESULTS

The authors found that speech arrest sites were substantially consistent with SLF-III anterior terminations (group 1, κ = 0.64 ± 0.03; group 2, κ = 0.73 ± 0.05) and moderately consistent with AF (group 1, κ = 0.51 ± 0.03; group 2, κ = 0.49 ± 0.05) and AF/SLF-III complex (group 1, κ = 0.54 ± 0.03; group 2, κ = 0.56 ± 0.05) terminations (all p < 0.0001). The DCS speech arrest sites of the group 2 patients mainly (85.1%) emerged at the anterior bank of the vPCG (vPCGa). In group 3, both terminations of AF and SLF-III converged onto the vPCGa, and their terminations well predicted the DCS speech output area of group 2 (AF, area under the curve [AUC] 86.5%; SLF-III, AUC 79.0%; AF/SLF-III complex, AUC 86.7%).

CONCLUSIONS

This study supports the key role of the left vPCGa as the speech output node by showing convergence between speech output mapping and anterior AF/SLF-III connectivity in the vPCGa. These findings may contribute to the understanding of speech networks and could have clinical implications in preoperative surgical planning.

Restricted access

Justin Aflatooni, Sarthak Mohanty, Ivan Angelov, Takashi Hirase, Kevin Bondar, Michael Kakareka, Jose Saucedo, David Casper, and Comron Saifi

OBJECTIVE

There is currently no consensus regarding the appropriate lower instrumented vertebra (LIV) for multilevel posterior cervical fusion (PCF) constructs between C7 and crossing the cervicothoracic junction (CTJ). The goal of the present study was to compare postoperative sagittal alignment and functional outcomes among adult patients presenting with cervical myelopathy undergoing multilevel PCF terminating at C7 versus spanning the CTJ.

METHODS

A single-institution retrospective analysis (January 2017–December 2018) was performed of patients undergoing multilevel PCF for cervical myelopathy that involved the C6–7 vertebrae. Pre- and postoperative cervical spine radiographs were analyzed for cervical lordosis, cervical sagittal vertical axis (cSVA), and first thoracic (T1) vertebral slope (T1S) in two randomized independent trials. Modified Japanese Orthopaedic Association (mJOA) and Patient-Reported Outcomes Measurement Information System (PROMIS) scores were used to compare functional and patient-reported outcomes at the 12-month postoperative follow-up.

RESULTS

Sixty-six consecutive patients undergoing PCF and 53 age-matched controls were included in the study. There were 36 patients in the C7 LIV cohort and 30 patients in the LIV spanning the CTJ cohort. Despite significant correction, patients undergoing fusion remained less lordotic than asymptomatic controls, with a C2–7 Cobb angle of 17.7° versus 25.5° (p < 0.001) and a T1S of 25.6° versus 36.3° (p < 0.001). The CTJ cohort had superior alignment corrections in all radiographic parameters at the 12-month postoperative follow-up compared with the C7 cohort: increase in T1S (ΔT1S 14.1° vs 2.0°, p < 0.001), increase in C2–7 lordosis (ΔC2–7 lordosis 11.7° vs 1.5°, p < 0.001), and decrease in cSVA (ΔcSVA 8.9 vs 5.0 mm, p < 0.001). There were no differences in the mJOA motor and sensory scores between cohorts pre- and postoperatively. The C7 cohort reported significantly better PROMIS scores at 6 months (22.0 ± 3.2 vs 11.5 ± 0.5, p = 0.04) and 12 months (27.0 ± 5.2 vs 13.5 ± 0.9, p = 0.01) postoperatively.

CONCLUSIONS

Crossing the CTJ may provide a greater cervical sagittal alignment correction in multilevel PCF surgeries. However, the improved alignment may not be associated with improved functional outcomes as measured by the mJOA scale. A new finding is that crossing the CTJ may be associated with worse patient-reported outcomes at 6 and 12 months of postoperative follow-up as measured by the PROMIS, which should be considered in surgical decision-making. Future prospective studies evaluating long-term radiographic, patient-reported, and functional outcomes are warranted.

Restricted access

Jeffrey P. Blount and Brandon G. Rocque

Restricted access

Sumit Singh, Mustafa S. M. Alhasan, Zhiyue Wang, Rebekah Clarke, Yin Xi, Joseph A. Maldjian, Ben Wagner, and Timothy Booth

OBJECTIVE

Task-based functional MRI (tb-fMRI) is now considered the standard, noninvasive technique in establishing language laterality in children for surgical planning. The evaluation can be limited due to several factors such as age, language barriers, and developmental and cognitive delays. Resting-state functional MRI (rs-fMRI) offers a potential path to establish language dominance without active task participation. The authors sought to compare the ability of rs-fMRI for language lateralization in the pediatric population with conventional tb-fMRI used as the gold standard.

METHODS

The authors performed a retrospective evaluation of all pediatric patients at a dedicated quaternary pediatric hospital who underwent tb-fMRI and rs-fMRI from 2019 to 2021 as part of the surgical workup for patients with seizures and brain tumors. Task-based fMRI language laterality was based on a patient’s adequate performance on one or more of the following: sentence completion, verb generation, antonym generation, or passive listening tasks. Resting-state fMRI data were postprocessed using statistical parametric mapping, FMRIB Software Library, and FreeSurfer as described in the literature. The laterality index (LI) was calculated from the independent component (IC) with the highest Jaccard Index (JI) for the language mask. Additionally, the authors visually inspected the activation maps for two ICs with the highest JIs. The rs-fMRI LI of IC1 and the authors’ image-based subjective interpretation of language lateralization were compared with tb-fMRI, which was considered the gold standard for this study.

RESULTS

A retrospective search yielded 33 patients with language fMRI data. Eight patients were excluded (5 with suboptimal tb-fMRI and 3 with suboptimal rs-fMRI data). Twenty-five patients (age range 7–19 years, male/female ratio 15:10) were included in the study. The language laterality concordance between tb-fMRI and rs-fMRI ranged from 68% to 80% for assessment based on LI of independent component analysis with highest JI and for subjective evaluation by visual inspection of activation maps, respectively.

CONCLUSIONS

The concordance rates between tb-fMRI and rs-fMRI of 68% to 80% show the limitation of rs-fMRI in determining language dominance. Resting-state fMRI should not be used as the sole method for language lateralization in clinical practice.