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Jeremiah N. Johnson and Michael Y. Wang

Bilateral pedicle fractures in the spine are uncommon in the absence of bony abnormality, previous surgery, or trauma. The authors report a case of spontaneous bilateral lumbar pedicle fracture in a 50-year-old sedentary woman, which caused intractable pain and did not respond to months of conservative management. The fractures were surgically treated using a percutaneous, minimally invasive technique with screws placed directly through the fractures into the vertebral body. The pedicles were strategically tapped to achieve the lag effect and reapproximate the posterior fragment with the anterior elements. The patient tolerated the procedure well and experienced early improvement of her symptoms, and follow-up imaging showed evidence of fracture healing. Transpedicular fixation and the use of the lag effect could be a useful strategy in the treatment of future cases involving poorly healing pedicle fractures causing persistent symptoms.

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Marcel F. Dvorak, Michael G. Johnson, Michael Boyd, Garth Johnson, Brian K. Kwon and Charles G. Fisher

Object. The primary goal of this study was to describe the long-term health-related quality of life (HRQOL) outcomes in patients who have suffered Jefferson-type fractures. These outcomes were compared with matched normative HRQOL data and with the patient's perceptions of their HRQOL prior to the injury. Variables that potentially influence these HRQOL outcomes were analyzed.

No standardized outcome assessments have been published for patients who suffer these fractures; their outcomes have long thought to be excellent following treatment. Determining the optimal surrogate measure to represent preinjury HRQOL in trauma patients is difficult.

Methods. A retrospective review, radiographic analysis, and cross-sectional outcome assessment were performed. The Short Form (SF)—36 and the American Academy of Orthopaedic Surgeons/North American Spine Society (AAOS/NASS) outcome instruments were filled out by patients at final follow-up examination (follow-up period 75 months, range 19–198 months) to represent their current status as well as their perceptions of preinjury status.

In 34 patients, the SF-36 physical component score and the AAOS/NASS pain values were significantly lower than normative values. There was no significant difference between normative and preinjury values. Spence criteria greater than 7 mm and the presence of associated injuries predicted poorer outcome scores during the follow-up period.

Conclusions. Long-term follow-up examination of patients with Jefferson fractures indicated that patients' status does not return to the level of their perceived preinjury health status or that of normative population controls. Those with other injuries and significant osseous displacement (≥ 7 mm total) may experience poorer long-term outcomes. Limitations of the study included a relatively low (60%) response rate and the difficulties of identifying an appropriate baseline outcome in a trauma population with which the follow-up outcomes can be compared.

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Michael T. Lawton

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Michael J. Rosner, Sheila D. Rosner and Alice H. Johnson

✓ Early results using cerebral perfusion pressure (CPP) management techniques in persons with traumatic brain injury indicate that treatment directed at CPP is superior to traditional techniques focused on intracranial pressure (ICP) management. The authors have continued to refine management techniques directed at CPP maintenance.

One hundred fifty-eight patients with Glasgow Coma Scale (GCS) scores of 7 or lower were managed using vascular volume expansion, cerebrospinal fluid drainage via ventriculostomy, systemic vasopressors (phenylephrine or norepinephrine), and mannitol to maintain a minimum CPP of at least 70 mm Hg. Detailed outcomes and follow-up data bases were maintained. Barbiturates, hyperventilation, and hypothermia were not used.

Cerebral perfusion pressure averaged 83 ± 14 mm Hg; ICP averaged 27 ± 12 mm Hg; and mean systemic arterial blood pressure averaged 109 ± 14 mm Hg. Cerebrospinal fluid drainage averaged 100 ± 98 cc per day. Intake (6040 ± 4150 cc per day) was carefully titrated to output (5460 ± 4000 cc per day); mannitol averaged 188 ± 247 g per day. Approximately 40% of these patients required vasopressor support.

Patients requiring vasopressor support had lower GCS scores than those not requiring vasopressors (4.7 ± 1.3 vs. 5.4 ± 1.2, respectively). Patients with vasopressor support required larger amounts of mannitol, and their admission ICP was 28.7 ± 20.7 versus 17.5 ± 8.6 mm Hg for the nonvasopressor group. Although the death rate in the former group was higher, the outcome quality of the survivors was the same (Glasgow Outcome Scale scores 4.3 ± 0.9 vs. 4.5 ± 0.7). Surgical mass lesion patients had outcomes equal to those of the closed head-injury group.

Mortality ranged from 52% of patients with a GCS score of 3 to 12% of those with a GCS score of 7; overall mortality was 29% across GCS categories. Favorable outcomes ranged from 35% of patients with a GCS score of 3 to 75% of those with a GCS score of 7. Only 2% of the patients in the series remained vegetative and if patients survived, the likelihood of their having a favorable recovery was approximately 80%. These results are significantly better than other reported series across GCS categories in comparisons of death rates, survival versus dead or vegetative, or favorable versus nonfavorable outcome classifications (Mantel—Haenszel χ2, p < 0.001). Better management could have improved outcome in as many as 35% to 50% of the deaths.

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J. Patrick Johnson, Chinyere Obasi, Michael S. Hahn and Paul Glatleider

Object. Thoracic sympathectomy has evolved as a treatment option for patients with hyperhidrosis and pain disorders. In the past, surgical procedures were highly invasive and caused significant morbidity, but the minimally invasive thoracoscopic procedure provides detailed visualization of the sympathetic ganglia and is associated with minimal postoperative morbidity.

Methods. The authors performed 112 thoracoscopic sympathectomy procedures in 65 patients, and the outcomes were equivalent to those previously established for open surgical techniques; however, the rate of surgery-related morbidity, length of hospital stay, and time until return to normal activity were substantially reduced. Complications and recurrence of symptoms were comparable with those demonstrated in previous reports. Overall patient satisfaction and willingness to undergo a repeated operative procedure ranged from 66 to 99%. Postoperatively, higher satisfaction rates were observed in patients with hyperhidrosis whereas in those with pain syndromes, satisfaction rates were lower.

Conclusions. Minimally invasive thoracoscopic sympathectomy procedures are useful in treating sympathetically mediated disorders, and the results indicate that the procedure is associated with reduced morbidity and similar outcome when compared with results obtained after open surgery. Hyperhidrosis is well treated, but patients with pain syndromes have significantly poorer outcomes.

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J. Patrick Johnson, Chinyere Obasi, Michael S. Hahn and Paul Glatleider

Thoracic sympathectomy has evolved as a treatment option for patients with hyperhidrosis and pain disorders. In the past surgical procedures were highly invasive and caused significant morbidity, but the minimally invasive thoracoscopic procedure provides detailed visualization of the sympathetic ganglia and is associated with minimal postoperative morbidity. In a previously published series the authors performed 60 thorascopic procedures in 39 patients; in this paper, they report the addition of 52 procedures performed in 26 patients, for a total of 112 procedures in 65 patients. Overall, the outcomes were equivalent to those for previously established open surgical techniques; however, the rate of surgery-related morbidity, length of hospital stay, and time until return to normal activity were substantially reduced. Complications and recurrence of symptoms were comparable with those demonstrated in previous reports. Overall patient satisfaction and willingness to undergo a repeat operative procedure ranged from 66 to 99%. Postoperatively, higher satisfaction rates were observed in patients with hyperhidrosis whereas in those with pain syndromes, satisfaction rates were lower. Minimally invasive thoracoscopic sympathectomy procedures are useful in treating sympathetically mediated disorders, and the results indicated that the procedure is associated with reduced morbidity and similar outcome when compared with results obtained after open surgery. Hyperhidrosis is well treated, but patients with pain syndromes have significantly poorer outcomes.

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Zhenjun Zhao, Michael S. Johnson, Biyi Chen, Michael Grace, Jaysree Ukath, Vivienne S. Lee, Lucinda S. McRobb, Lisa M. Sedger and Marcus A. Stoodley

OBJECT

Stereotactic radiosurgery (SRS) is an established intervention for brain arteriovenous malformations (AVMs). The processes of AVM vessel occlusion after SRS are poorly understood. To improve SRS efficacy, it is important to understand the cellular response of blood vessels to radiation. The molecular changes on the surface of AVM endothelial cells after irradiation may also be used for vascular targeting. This study investigates radiation-induced externalization of phosphatidylserine (PS) on endothelial cells using live-cell imaging.

METHODS

An immortalized cell line generated from mouse brain endothelium, bEnd.3 cells, was cultured and irradiated at different radiation doses using a linear accelerator. PS externalization in the cells was subsequently visualized using polarity-sensitive indicator of viability and apoptosis (pSIVA)-IANBD, a polarity-sensitive probe. Live-cell imaging was used to monitor PS externalization in real time. The effects of radiation on the cell cycle of bEnd.3 cells were also examined by flow cytometry.

RESULTS

Ionizing radiation effects are dose dependent. Reduction in the cell proliferation rate was observed after exposure to 5 Gy radiation, whereas higher radiation doses (15 Gy and 25 Gy) totally inhibited proliferation. In comparison with cells treated with sham radiation, the irradiated cells showed distinct pseudopodial elongation with little or no spreading of the cell body. The percentages of pSIVA-positive cells were significantly higher (p = 0.04) 24 hours after treatment in the cultures that received 25- and 15-Gy doses of radiation. This effect was sustained until the end of the experiment (3 days). Radiation at 5 Gy did not induce significant PS externalization compared with the sham-radiation controls at any time points (p > 0.15). Flow cytometric analysis data indicate that irradiation induced growth arrest of bEnd.3 cells, with cells accumulating in the G2 phase of the cell cycle.

CONCLUSIONS

Ionizing radiation causes remarkable cellular changes in endothelial cells. Significant PS externalization is induced by radiation at doses of 15 Gy or higher, concomitant with a block in the cell cycle. Radiation-induced markers/targets may have high discriminating power to be harnessed in vascular targeting for AVM treatment.

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Matthew L. Mundwiler, Khawar Siddique, Jeffrey M. Dym, Brian Perri, J. Patrick Johnson and Michael H. Weisman

✓ Ankylosing spondylitis (AS) is a systemic inflammatory disorder with frequent spinal axis symptoms. In this paper, the authors explored the spinal manifestations of AS and its characteristic anatomical lesions, radiological findings, and complications. They also offer a comprehensive report of the medical and surgical treatments with a focus on deformity correction.

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Matthew T. Stib, Michael Johnson, Alan Siu, M. Isabel Almira-Suarez, Zachary Litvack, Ameet Singh and Jonathan H. Sherman

The authors describe the case of a large WHO Grade III anaplastic oligoastrocytoma extending through the anterior skull base and into the right nasal cavity and sinuses. Glial neoplasms are typically confined to the intracranial compartment within the brain parenchyma and rarely extend into the nasal cavity without prior surgical or radiation therapy. This 42-year-old woman presented with progressive headaches and sinus congestion. MR imaging findings revealed a large intracranial lesion with intranasal extension. Endoscopic nasal biopsy revealed pathology consistent with an infiltrating glioma. The patient subsequently underwent a combined transcranial/endonasal endoscopic approach for resection of this lesion. Pathological diagnosis revealed a WHO Grade III oligoastrocytoma. This report reviews the mechanisms of extradural glioma extension. To the authors' knowledge, it is the second report of a high-grade glioma exhibiting nasal extension without prior surgical or radiation treatment.