Cervical myelomeningocele (MMC) is an uncommon congenital malformation of the spinal cord and accounts for a small proportion of neural tube defects. These lesions mostly occur in the dorsal part of the body. Only a single case of an anterior cervical MMC has been previously reported. The authors report a second case of anterior cervical MMC diagnosed when the patient began to experience symptoms of bilateral hand weakness in adulthood. In this patient, MR imaging of the cervical spine showed an anterior cervical MMC at the C6–7 level with hydrocephalus, thinning of the genu and trunk of the corpus callosum, maldevelopment of the cerebellar tonsils, and expansion of the fourth ventricle, posterior cranial fossa, and subarachnoid space. A CT scan and a 3D CT reconstruction of the cervical spine clearly demonstrated contiguous fusions of multiple lower-cervical vertebrae and neural arches, which was consistent with Type III Klippel-Feil syndrome. The patient was advised to undergo operative treatment to prevent the progression of her neurological deficit. However, after being notified of the potential neurological risks, the patient declined surgery and opted for conservative treatment with a hard neck collar. At 4 months' follow-up, the patient's neurological deficit remains stable with the MMC left untreated. The authors presume that the possible pathogenesis of anterior cervical MMC may greatly differ from that of posterior lesions. This lesion could also be associated with multiple other spinal abnormalities, which highlights the importance of comprehensive preoperative radiological examinations.
Jun Jiang, Zezhang Zhu, Bangping Qian, Zhen Liu, and Yong Qiu
Sebastian Rubino, Jiang Qian, Carlos D. Pinheiro-Neto, Tyler J. Kenning, and Matthew A. Adamo
Hypothalamic hamartomas are benign tumors known to cause gelastic or dacrystic seizures, precocious puberty, developmental delay, and medically refractory epilepsy. These tumors are most often sporadic but rarely can be associated with Pallister-Hall syndrome, an autosomal dominant familial syndrome caused by truncation of glioblastoma transcription factor 3, a downstream effector in the sonic hedgehog pathway. In this clinical report, the authors describe two brothers with a different familial syndrome. To the best of the authors’ knowledge, this is the first report in the literature describing a familial syndrome caused by germline mutations in the Smoothened (SMO) gene and the first familial syndrome associated with hypothalamic hamartomas other than Pallister-Hall syndrome. The authors discuss the endoscopic endonasal biopsy and subtotal resection of a large hypothalamic hamartoma in one of the patients as well as the histopathological findings encountered. Integral to this discussion is the understanding of the hedgehog pathway; therefore, the underpinnings of this pathway and its clinical associations to date are also reviewed.
Alan S. Boulos, Eric M. Deshaies, Jiang Qian, and A. John Popp
✓ In this report, the authors discuss a novel use of intradural vertebral artery (VA) stent placement to protect a tumor-encased vessel from injury during lesion resection. The tumor was a rare foramen magnum region xanthogranuloma and a component of Erdheim—Chester disease (ECD). This 64-year-old man presented with large masses encasing and compressing the intracranial segments of each VA. Preoperatively, a left VA stent was placed to protect the arterial wall during resection of the tumor. Histopathological study results on the subtotally resected mass were consistent with xanthogranuloma, a rare benign histiocytic tumor frequently occurring in patients with ECD. Further radiographic evaluation in the patient revealed an osteolytic lesion of the eleventh thoracic vertebra supporting the diagnosis of ECD disease. Based on this case study, the authors recommend the following: 1) tumor-encased vessels can be protected preoperatively by stent placement to assist with tumor debulking; and 2) patients diagnosed with a xanthogranuloma should be evaluated for multisystem involvement consistent with ECD.
Zhuo-jie Liu, Bang-ping Qian, Yong Qiu, Sai-hu Mao, Jun Jiang, and Bin Wang
Relocation of the apex is often found in patients with ankylosing spondylitis (AS)–associated thoracolumbar/lumbar kyphosis after corrective surgery. This study evaluates the influence of different postoperative apex locations on surgical and clinical outcomes of osteotomy for patients with AS and thoracolumbar kyphosis.
Sixty-two patients with a mean age of 34.6 ± 9.7 years (range 17–59 years) and a minimum of 2 years of follow-up, who underwent 1-level lumbar pedicle subtraction osteotomy for AS-related thoracolumbar kyphosis, were enrolled in the study, as well as 62 age-matched healthy individuals. Patients were divided into 2 groups according to the postoperative location of the apex (group 1, T8 or above; group 2, T9 or below). Demographic data, radiographic measurements (including 3 postoperative apex-related parameters), and clinical outcomes were compared between the 2 groups preoperatively, postoperatively, and at the last follow-up. Furthermore, a subgroup analysis was performed among patients with a postoperative apex located at T6–11 and postoperatively the entire AS cohort was compared with normal controls regarding the apex location of the thoracic spine.
In the majority of the enrolled patients, the apex location changed from T12–L2 preoperatively to T6–9 postoperatively. The sagittal vertical axis (SVA) differed significantly both postoperatively (25.7 vs 59.0 mm, p = 0.001) and at the last follow-up (34.6 vs 59.9 mm, p = 0.003) between the 2 groups, and the patients in group 1 had significantly smaller horizontal distance between the C7-vertical line and the apex (DCA) than the patients in group 2 (67.5 vs 103.7 mm, p = 0.001). Subgroup analysis demonstrated similar results, showing that the patients with a postoperative apex located at T8 or above had an average SVA < 47 mm. Notably, a significant correlation was found between postoperative SVA and DCA (r = 0.642, p = 0.001). Patients who underwent an osteotomy at L3 had limited apex relocation but larger SVA correction than those at L1 or L2. However, no significant difference was found in health-related quality of life between the 2 groups.
AS patients with an apex located at T8 or above after surgery tended to have better SVA correction (within 47 mm) than those who had a more caudally located apical vertebra. For ideal postoperative apex relocation, a higher (closer to or at the preoperative apex) level of osteotomy is more likely to obtain the surgical goal.
Bang-ping Qian, Ji-chen Huang, Yong Qiu, Bin Wang, Yang Yu, Ze-zhang Zhu, Sai-hu Mao, and Jun Jiang
To describe the incidence of complications in spinal osteotomy for thoracolumbar kyphosis caused by ankylosing spondylitis (AS) and to investigate the risk factors for these complications.
From April 2000 to July 2017, 342 consecutive AS patients with a mean age (± SD) of 35.4 ± 9.8 years (range 17–71 years) undergoing spinal osteotomy were enrolled. Patients with complications within the 1st postoperative year were identified. Demographic, radiological, and surgical data were compared between patients with and without complications. The complications were classified into intraoperative and postoperative complications.
A total of 310 consecutive pedicle subtraction osteotomy (PSO) and 37 multiple Smith-Petersen osteotomy (SPO) procedures were performed in 342 patients. Overall, 47 complications were identified in 47 patients (13.7%), including 31 intraoperative complications and 16 postoperative complications. Patients with complications were older than those without (p = 0.006). A significant difference was observed in preoperative global kyphosis (GK), lumbar lordosis (LL), sagittal vertical axis (SVA), and the correction of these radiographic parameters between patients with and without complications (p < 0.05). Two-level PSO (p = 0.022) and an increased number of instrumented vertebrae (p = 0.019) were significantly associated with an increased risk of complications.
The overall incidence of complications was 13.7%. Age; preoperative GK, LL, and SVA; the correction of GK, LL, and SVA; 2-level PSO; and number of instrumented vertebrae were risk factors. Therefore, the potential risk of extensive surgeries with large correction and long fusion in older AS patients with severe GK should be seriously considered in surgical decision-making.
Eric M. Deshaies, Matthew A. Adamo, Jiang Qian, and Darryl A. DiRisio
✓ This 79-year-old woman presented with progressively worsening dementia, abulia, flat affect, urinary incontinence, and profuse watery diarrhea. Results of computerized tomography and magnetic resonance studies indicated an extraaxial, dural-based mass compressing the right frontal lobe and consistent with a convexity meningioma. A right frontal craniotomy was performed and the dural-based mass was resected. Histopathological features on immunostaining of the lesion were consistent with a carcinoid tumor (low-grade neuroendocrine carcinoma). Further evaluation revealed no primary carcinoid tumor in the foregut from which they typically originate. The authors concluded that this intracranial carcinoid tumor was the primary lesion despite its unusual location and that it should be included in the differential diagnosis of dural-based, extraaxial brain lesions.
Abigail Hellman, Teresa Maietta, Alicia Clum, Kanakaharini Byraju, Nataly Raviv, Michael D. Staudt, Erin Jeannotte, Goutam Ghoshal, Damian Shin, Paul Neubauer, Emery Williams, Tamas Heffter, Clif Burdette, Jiang Qian, Julia Nalwalk, and Julie G. Pilitsis
The authors’ laboratory has previously demonstrated beneficial effects of noninvasive low intensity focused ultrasound (liFUS), targeted at the dorsal root ganglion (DRG), for reducing allodynia in rodent neuropathic pain models. However, in rats the DRG is 5 mm below the skin when approached laterally, while in humans the DRG is typically 5–8 cm deep. Here, using a modified liFUS probe, the authors demonstrated the feasibility of using external liFUS for modulation of antinociceptive responses in neuropathic swine.
Two cohorts of swine underwent a common peroneal nerve injury (CPNI) to induce neuropathic pain. In the first cohort, pigs (14 kg) were iteratively tested to determine treatment parameters. liFUS penetration to the L5 DRG was verified by using a thermocouple to monitor tissue temperature changes and by measuring nerve conduction velocity (NCV) at the corresponding common peroneal nerve (CPN). Pain behaviors were monitored before and after treatment. DRG was evaluated for tissue damage postmortem. Based on data from the first cohort, a treatment algorithm was developed, parameter predictions were verified, and neuropathic pain was significantly modified in a second cohort of larger swine (20 kg).
The authors performed a dose-response curve analysis in 14-kg CPNI swine. Specifically, after confirming that the liFUS probe could reach 5 cm in ex vivo tissue experiments, the authors tested liFUS in 14-kg CPNI swine. The mean ± SEM DRG depth was 3.79 ± 0.09 cm in this initial cohort. The parameters were determined and then extrapolated to larger animals (20 kg), and predictions were verified. Tissue temperature elevations at the treatment site did not exceed 2°C, and the expected increases in the CPN NCV were observed. liFUS treatment eliminated pain guarding in all animals for the duration of follow-up (up to 1 month) and improved allodynia for 5 days postprocedure. No evidence of histological damage was seen using Fluoro-Jade and H&E staining.
The results demonstrate that a 5-cm depth can be reached with external liFUS and alters pain behavior and allodynia in a large-animal model of neuropathic pain.
Guo-Bao Wang, Ai-Ping Yu, Chye Yew Ng, Gao-Wei Lei, Xiao-Min Wang, Yan-Qun Qiu, Jun-Tao Feng, Tie Li, Qing-Zhong Chen, Qian-Ru He, Fei Ding, Shu-Sen Cui, Yu-Dong Gu, Jian-Guang Xu, Su Jiang, and Wen-Dong Xu
Contralateral C7 (CC7) nerve root has been used as a donor nerve for targeted neurotization in the treatment of total brachial plexus palsy (TBPP). The authors aimed to study the contribution of C7 to the innervation of specific upper-limb muscles and to explore the utility of C7 nerve root as a recipient nerve in the management of TBPP.
This was a 2-part investigation. 1) Anatomical study: the C7 nerve root was dissected and its individual branches were traced to the muscles in 5 embalmed adult cadavers bilaterally. 2) Clinical series: 6 patients with TBPP underwent CC7 nerve transfer to the middle trunk of the injured side. Outcomes were evaluated with the modified Medical Research Council scale and electromyography studies.
In the anatomical study there were consistent and predominantly C7-derived nerve fibers in the lateral pectoral, thoracodorsal, and radial nerves. There was a minor contribution from C7 to the long thoracic nerve. The average distance from the C7 nerve root to the lateral pectoral nerve entry point of the pectoralis major was the shortest, at 10.3 ± 1.4 cm. In the clinical series the patients had been followed for a mean time of 30.8 ± 5.3 months postoperatively. At the latest follow-up, 5 of 6 patients regained M3 or higher power for shoulder adduction and elbow extension. Two patients regained M3 wrist extension. All regained some wrist and finger extension, but muscle strength was poor. Compound muscle action potentials were recorded from the pectoralis major at a mean follow-up of 6.7 ± 0.8 months; from the latissimus dorsi at 9.3 ± 1.4 months; from the triceps at 11.5 ± 1.4 months; from the wrist extensors at 17.2 ± 1.5 months; from the flexor carpi radialis at 17.0 ± 1.1 months; and from the digital extensors at 22.8 ± 2.0 months. The average sensory recovery of the index finger was S2. Transient paresthesia in the hand on the donor side, which resolved within 6 months postoperatively, was reported by all patients.
The C7 nerve root contributes consistently to the lateral pectoral nerve, the thoracodorsal nerve, and long head of the triceps branch of the radial nerve. CC7 to C7 nerve transfer is a reconstructive option in the overall management plan for TBPP. It was safe and effective in restoring shoulder adduction and elbow extension in this patient series. However, recoveries of wrist and finger extensions are poor.