Postoperative Palsy Research Articles

Single institutional analysis of trends over 45 years in etiology of vocal fold paralysis

It is important to assess the causes of vocal fold paralysis. Many studies have reported causes of paralysis, but few reports have shown changes in longitudinal etiology in a single institution. We investigated the medical records of 797 patients with vocal fold paralysis from 1990 to 2005 at the voice and bronchoesophageal outpatient clinics at the University of Tokyo Hospital. We evaluated the etiology of paralysis, and compared our results with a previous study by Hirose in our clinic from 1961 to 1989 to assess changes in etiology. The postoperative group comprised 466 patients (58.5%), while the non-surgical group comprised 331 (41.5%) patients. In the postoperative group, the most common cause of paralysis was thyroid surgery (106 cases), and other common causes were surgery for aortic aneurysm (61 cases) and tracheal intubation (58 cases). In the non-surgical group, idiopathic paralysis (134 cases) was the most common cause. Other common causes were lung cancer (34 cases) and cerebrovascular disease (24 cases). In a previous study from our clinic, the rate of postoperative paralysis was 43.5%. In the current analysis, the percentage of postoperative patients has increased remarkably compared with that of the previous report while the rate of idiopathic paralysis, has decreased by half. The increase in postoperative cases of paralysis may be caused by the increasing frequency of operations for many diseases, due to the progress of medical techniques in recent years. The decrease in idiopathic cases may be related to the advances of diagnostic devices such as CT and MRI.

Modified eggshell technique through posterior approach for the hard thoracic disc herniation

Objective To evaluate the clinical outcomes of modified eggshell technique through posterior approach for the treatment of hard thoracic disc herniation. Methods From January 2006 to June 2009, 22 patients admitted for hard thoracic disc herniation were reviewed, including 13 males and 9 females, with an average age of 49.5 years (range, 33-69). The courses of disease were 11 months on the average (range, 3-18 ). The lesions located in T8-9 for 4 cases, T9-10 for 9, T10-11 for 7, T11-12 for 2. Each of the patients underwent X-ray, CT scanning and MRI examination before surgery. There were 16 cases of central type, and 6 cases of paracentral type. All patients were treated surgically by modified eggshell technique via posterior approach. Results The mean operative time was 210 min (range, 180-300 min), with a mean blood loss of 860 ml (range, 600-1200 ml). All surgeries were performed successfully without neurological symptoms aggravation. Surgical complications included dural laceration in 2 cases, both dural lacerations were repaired intraoperatively, epidural hematoma in 1 case with lower extremity neurological symptoms, full neurologic recovery was observed after surgical removal of the hematoma. All patients were followed up for average 27.5 months (range, 12-54). The mean JOA score increased from 3.36±1.79 before operation to 7.45±2.99 after the operation at 12 months follow up, and the mean improvement rate of neurological status was 58.3%±30.7%. There was significant difference in JOA score before and after surgery(t=10. 12,P＜0.01 ).The results of 14 cases were ranked as good, 6 as fair, 2 as unchanged, and none as worsened. All cases obtained bony fusion without instrument failure. Conclusion Modified eggshell technique enable ventral and dorsal spinal decompression from the posterior approach in cases of hard thoracic disc herniation, with reduction of the rate of postoperative paralysis. Key words: Thoracic vertebrae; lntervertebral disk displacement; Sclerosis

Postoperative paralysis following posterior decompression with instrumented fusion for thoracic myelopathy caused by ossification of the posterior longitudinal ligament

A 60-year-old man presented with thoracic myelopathy due to ossification of the posterior longitudinal ligament (OPLL). His spinal cord was severely impinged anteriorly by a beak-type OPLL and posteriorly by ossification of the ligamentum flavum at T4/5. He underwent surgical posterior decompression with instrumented fusion (PDF). Immediately after surgery, he developed a Brown-Séquard-type paralysis, which spontaneously resolved without requiring the addition of OPLL extirpation. This example highlights that the risk of postoperative neurological deterioration cannot be eliminated even when PDF is selected as the surgical procedure for thoracic OPLL, especially in instances in which the spinal cord is severely compressed.

Sugammadex in anesthesia practice

Importance of the field: Neuromuscular blocking agents are currently used during anesthesia but put patients at risk of postoperative paralysis. If the residual neuromuscular blockade is not reversed properly at the end of anesthesia, there is a risk of hypoxemia and pulmonary complication. Sugammadex is able to fully reverse different degrees of neuromuscular blockade induced by steroidal neuromuscular blocking agents.Areas covered in this review: This review provides a background to the use of neuromuscular blocking agents during anesthesia. It also describes the mechanism of reversal and the clinical efficacy of sugammadex, and discusses the future changes in clinical anesthesia induced by this new selective binding agent.What the reader will gain: An understanding of the rationale and use of sugammadex as a reversal agent of different degrees of neuromuscular blockade and the use of the high-dose rocuronium–sugammadex combination as an alternative to succinylcholine for rapid sequence induction.Take home message: Sugammadex provides an original mechanism of reversing the effect of neuromuscular steroidal agent by direct inactivation in plasma. Although its effect is spectacular, it is questionable whether this drug will change current practice.

The Trapezius-Splitting Approach: Modifications for Treating Disorders and Traumas Occurring in the Lateral Supraspinatus Fossa

Disorders or traumas requiring surgery other than suprascapular entrapment neuropathy that occur in the lateral supraspinatus fossa are decidedly uncommon. Because a wider operative field is necessary for treating these disorders, we have applied a trapezius-splitting approach with some modifications. The procedure comprises a saber cut incision along with trapezius-splitting of 5 cm to 6 cm proximally from the position coinciding with the posterior margin of the acromioclavicular joint. At the lateral aspect of this division, a Gelpi retractor is set on the clavicle and the scapular spine to widen the narrow interspace between them. The underlying adipose tissue and supraspinatus muscle are forced aside en bloc posteriorly. Four patients were surgically treated using this approach and were postoperatively followed up for 22.2 months ± 7.8 months. A sufficient operative field for the major maneuver was secured in all four patients. None developed postoperative paralysis or atrophy of the trapezius, supraspinatus, or infraspinatus muscles. The three patients treated for nonunion or delayed union of coracoid fracture exhibited successful union, and the patient treated for osteochondroma of the clavicle had no recurrence. The main advantages of this procedure are minimal trauma to the musculature, a clearly visible field of the most lateral fossa, and the ability to approach the anterior or posterior shoulder region through the extended skin incision and deltoid-splitting approach if required. Results indicate that the procedure would be advantageous in the surgical treatment of disorders and traumas occurring in the lateral supraspinatus fossa.

Transient phrenic nerve paralysis after carotid endarterectomy in a patient with asthma

To the Editor: Transient phrenic nerve paralysis occurred in a patient with asthma after carotid endarterectomy (CEA). The patient, a 64-year-old male with a height of 164 cm and weight of 69 kg, had been suffering from asthma for 15 years for which he was taking 400 mg of theophylline daily. A respiratory examination showed a reduced percentage forced expiratory volume in 1 second (%FEV1.0: 61.2%), and he was assigned to class II in Hugh–Jone’s classification. The patient was scheduled for CEA due to cerebral infarction with left lower extremity paralysis and transient dizziness 1 year earlier. With respect to the patient’s positioning during surgery, the anterior edge of the skin on the sternocleidomastoid muscle was located at the highest point by placing a shoulder pillow under the right shoulder in the supine position and rotating the head 30 to the left side; the jaw was tracted in the cephalic direction and the right shoulder was also tracted in the caudal direction. Anesthetic management was performed without difficulty for 4 h and 2 min, and surgery was completed without complications in 2 h and 43 min. Since the neurosurgeons were concerned about possible respiratory disorders, such as atelectasis, due to the patient’s asthma and wanted to ensure that there was no problem, they requested an X-ray before extubation. The post-operative X-ray revealed right diaphragm elevation at the end-inspiratory phase during spontaneous breathing (Fig. 1). Since there were no problems in emergence from anesthesia or in respiratory functions, such as blood gas data or respiratory pattern or tidal volume, extubation was attempted in the sitting position. There was also no respiratory disorder after extubation. Diaphragm elevation was improved the next day. Post-operative transient phrenic nerve paralyses mainly occur after cardiac surgery due to direct injury or hypothermia, mainly on the left side, and can be caused after other surgery due to traction or compression caused by the patient’s position [1, 2]. Unilateral diaphragmatic paralysis in adults generally has minimal symptoms or no symptoms, but bilateral or unilateral diaphragmatic paralysis in children can cause serious medical problems [1, 3]. The cause in the patient described here is thought to be traction by the head position. Although extubation was performed in the sitting position because of the possibility of respiratory disorder caused by unilateral phrenic nerve paralysis with asthma, there was no problem in the respiratory system after extubation. In the present case, a post-operative X-ray, which was taken because the patient had asthma, revealed, by chance, transient phrenic nerve paralysis. However, X-rays are not standard procedures following CEA in many institutions. Presented at the Annual Meeting of the Japan Society for Clinical Anesthesia, Osaka, October 24, 2004.

Posterior decompression with kyphosis correction for thoracic myelopathy due to ossification of the ligamentum flavum and ossification of the posterior longitudinal ligament at the same level

OBJECT The object of this study was to evaluate the efficacy and safety of posterior decompression with kyphosis correction for thoracic myelopathy due to ossification of the ligamentum flavum (OLF) and ossification of the posterior longitudinal ligament (OPLL) at the same level. METHODS Between January 2003 and December 2005, 11 patients (8 men and 3 women) with thoracic myelopathy due to OLF and OPLL at the same level underwent posterior decompressive laminectomy and excision of OLF. Posterior instrumentation was also performed for stabilization of the spine and reducing the thoracic kyphosis angle by approximately 5-15 degrees (kyphosis correction), and spinal fusion was performed in all cases. The follow-up period ranged from 2 to 4 years (mean 2.8 years). The outcomes were evaluated using a recovery scale based on the Japanese Orthopaedic Association classification. The score of each patient was calculated before surgery, 1 year after surgery, and at the final follow-up visit. RESULTS After surgery, the thoracic kyphosis in the stabilization area was reduced from 30.0 +/- 4.02 degrees to 20.8 +/- 2.14 degrees on average. The mean score on the Japanese Orthopaedic Association scale improved from 3.5 +/- 1.69 preoperatively to 8.5 +/- 1.63 at the final follow-up, with a recovery rate of 68.0%. The results were good in 9 patients and fair in 2 patients. Postoperative MR imaging showed that the spinal cord was shifted posteriorly and decompressed completely in all cases. Myelopathy was not aggravated in any case after surgery. CONCLUSIONS A considerable degree of neurological recovery was observed after posterior decompression and kyphosis correction. The procedure is easy to perform with a low risk of postoperative paralysis. The authors therefore suggest that the procedure is useful for patients whose spinal cords are severely impinged by OLF and OPLL at the same level.

A Modified Decompression Surgery for Thoracic Myelopathy Caused by Ossification of Posterior Longitudinal Ligament

Case report and review. We report a case with severe thoracic myelopathy because of ossification of the posterior longitudinal ligament (OPLL) of the spine, in which the OPLL was removed via a modified decompression approach, with sufficient decompression of the spinal cord and a satisfactory outcome was achieved. Many different decompressive surgeries may be applied for thoracic myelopathy caused by OPLL. However, there are variations among patients with thoracic myelopathy because of OPLL, and the possibility of postoperative paralysis remains a major risk, and to date, the effective treatment option for thoracic myelopathy caused by OPLL is still controversial. The patient was a 60-year-old woman with isolated OPLL at T10/T11 with anteriorly compression in the spinal cord. Posterior decompression by laminectomy and anterior decompression by extirpation of the OPLL were performed by a posterior-lateral approach. First, spinal cord retrocession was achieved to relieve the compression of OPLL by posterior decompression. Second, the posterior 2/3 of involved vertebral bodies and the T10/T11 intervertebral disc were resected with the anterior-lateral approach. Then, the OPLL was extirpated from the anterior direction in order to relieve the spinal cord compression completely, and the resected ribs were used for the anterior column reconstruction. Finally, a titanium device was secured over the area of surgery to stabilize the spinal column. Complete removal of the ossification was achieved in the present patient. Satisfactory surgical outcome of this patient was confirmed by a follow-up of 3 years after operation. The present case suggests that posterior decompression, anterior extirpation of OPLL, and interbody fusion with spinal instrumentation only via a modified posterior-lateral approach is a novel, safe, and effective procedure for surgical treatment of thoracic OPLL.

Paraspinal Muscle Impingement Causing Acute Brown-Sequard Syndrome After Posterior Cervical Decompression

A case report. To present a previously unreported cause of neurologic compromise after cervical spine surgery. Several different causes of postoperative neurologic deficit have been reported in the literature. The authors present a case of acute postoperative paralysis after posterior cervical decompression by a mechanism that has not yet been reported in the literature. A 54-year-old muscular, short-statured man underwent posterior cervical laminectomy from C3-C5 without instrumentation and left C5 foraminotomy. Within hours of leaving the operating room, he began to develop postoperative neurologic deficits in his extremities, which progressed to a classic Brown-Sequard syndrome. Magnetic resonance imaging revealed regional kyphosis and large swollen paraspinal muscles impinging on the spinal cord without epidural hematoma. Emergent operative re-exploration confirmed these findings; large, swollen paraspinal muscles, a functioning drain, and no hematoma were found. The patient was treated with immediate corticosteroids at the time of initial diagnosis, and emergent re-exploration and debulking of the paraspinal muscles. The patient had complete recovery of neurologic function to his preoperative baseline after the second procedure but required a third procedure in which anterior discectomy and fusion at C4-C5 was performed, which led to improvement of his preoperative symptoms. When performing posterior cervical decompression, surgeons must be aware of the potential for loss of normal lordosis and anterior displacement of paraspinal muscles against the spinal cord, especially in muscular patients.

C5 palsy after cervical laminoplasty

We have reviewed 1858 patients who had undergone a cervical laminoplasty and identified 43 (2.3%) who had developed a C5 palsy with a MMT (MRC) grade of 0 to 2 in the deltoid, with or without involvement of the biceps, but with no loss of muscular strength in any other muscles. The clinical features and radiological findings of patients with (group P; 43 patients) and without (group C; 100 patients) C5 palsy were compared. CT scanning of group P revealed a significant narrowing of the intervertebral foramen of C5 (p < 0.005) and a larger superior articular process (p < 0.05). On MRI, the posterior shift of the spinal cord at C4-5 was significantly greater in group P, than in group C (p < 0.01). This study is the first to correlate impairment of the C5 nerve root with a C5 palsy. It may be that early foraminotomy in susceptible individuals and the avoidance of tethering of the cord by excessive laminoplasty may prevent a post-operative palsy of the C5 nerve root.

Intraoperative facial nerve monitoring in parotid gland surgery

To re-evaluate the value and the methods of intraoperative facial nerve monitoring in parotid gland surgery. Sixty-five cases received intraoperative facial nerve monitoring in parotidectomy (test group) since 2000 - 2008. The facial nerve was identified through central trunk method (n = 18), branch method (n = 35) and mixed method (n = 12). Most patients accepted general anesthesia by incubation. The operating duration and minimum electronic stimulation threshold values of EMG in evoked facial muscle were recorded. Facial nerve was identified though branch method (n = 44) and no intraoperative facial nerve monitoring was performed in parotidectomy (control group). There were four cases (6.1%) of mild temporary paralysis and no permanent post-operative paralysis of facial nerve in the test group. The average operating duration was 1.8 hour. The minimum reactive electronic stimulation threshold of EMG in evoked facial muscle was 0.08 mA. The range of suitable electronic stimulation threshold of EMG was from 0.2 mA to 1.0 mA. While there were nine cases (20.5%) of mild temporary paralysis and two cases (4.5%) of permanent post-operative paralysis of facial nerve in the control group and the average operating duration was 3.0 hours. Intraoperative facial nerve monitoring (IFNM) in parotidectomy can assist a surgeon to confirm and identify the facial nerve and exercise precautions so as to shorten operating duration and prevent potential surgical complications.

Knowledge of residual curarization: an Italian survey

The use of neuromuscular blocking agents (NMBAs) is widespread in anesthetic practice; little is known about the current use of these drugs in Italy. This survey was conducted to obtain information about the most commonly used clinical tests and the train-of-four (TOF) ratios that are considered as being reliable for assessing recovery from neuromuscular blockade at the end of anesthesia and the estimated occurrence rates of post-operative paralysis in Italian hospitals. The questionnaire was given to Italian anesthesiologists attending the 62nd National Congress of the Italian Society of Anesthesia, Analgesia and Intensive Therapy. Collected data were stratified by age and the total number of surgical procedures performed in the hospitals concerned. Seven hundred and fifty-four correctly compiled questionnaires were collected (response rate 88.7%). Seventy three percent of the respondents only used clinical tests for monitoring the level of neuromuscular blockade. The main clinical tests cited for the evaluation of residual paralysis were keeping the head lifted up for 5 s, protruding the tongue and opening the eyes. TOF was used by 35% of the respondents on a routine basis. Only 24% of the interviewed anesthesiologists reported that before extubation, a TOF ratio of at least 0.9 should be reached. Most Italian anesthetists assess the recovery from neuromuscular blockade only by clinical signs. There is poor awareness about the inability of such techniques to indicate even a significant amount of residual neuromuscular block. A more extensive use of quantitative instrumental monitoring is required for the more rational use of NMBAs.

Posterior decompression with instrumented fusion for thoracic myelopathy caused by ossification of the posterior longitudinal ligament

We evaluated the clinical results of posterior decompression with instrumented fusion (PDF) for thoracic myelopathy due to ossification of the posterior longitudinal ligament (OPLL). A total of 24 patients underwent PDF, and their surgical outcomes were evaluated by the Japanese Orthopaedic Association (JOA) scores (0-11 points) and by recovery rates calculated at 3, 6, 9 and 12 months after surgery and at a mean final follow-up of 4 years and 5 months. The mean JOA score before surgery was 3.7 points. Although transient paralysis occurred immediately after surgery in one patient (3.8%), all patients showed neurological recovery at the final follow-up with a mean JOA score of 8.0 points and a mean recovery rate of 58.1%. The mean recovery rate at 3, 6, 9 and 12 months after surgery was 36.7, 48.8, 54.0 and 56.8%, respectively. The median time point that the JOA score reached its peak value was 9 months after surgery. No patient chose additional anterior decompression surgery via thoracotomy. The present findings demonstrate that despite persistent anterior impingement of the spinal cord by residual OPLL, PDF can result in considerable neurological recovery with a low risk of postoperative paralysis. Since neurological recovery progresses slowly after PDF, we suggest that additional anterior decompression surgery is not desirable during the early stage of recovery.

A new approach to anesthesia management in myasthenia gravis: reversal of neuromuscular blockade by sugammadex

A neuromuscular blocking drug (NMBD) induced neuromuscular blockade (NMB) in patients with myasthenia gravis usually dissipates either spontaneously or by administration of neostigmine. We administered sugammadex to a patient with myasthenia gravis to reverse a rocuronium-induced profound NMB. NMBDs predispose such patients to severe postoperative residual paralysis and respiratory complications. Sugammadex binds steroidal NMBDs and, therefore reverses a rocuronium or vecuronium-induced NMB, without interfering with cholinergic transmission. A rapid and complete recovery from profound NMB was achieved and no adverse events were observed. This case suggests that sugammadex is a safe and effective antagonist of a rocuronium induced NMB blockade in patients with myasthenia gravis.

Major Neurologic Deficit Immediately After Adult Spinal Surgery

Retrospective study of adult patients who underwent spinal surgery over a 10-year period at a single institution. New onset postoperative paralysis remains one of the most feared complications of spinal surgery. The goal of this study was to determine the incidence and etiology of new onset major neurologic deficit immediately after adult spinal surgery. Previous studies, focusing on specific disease entities, have shown incidence rates of significant spinal cord or cauda equina injury after spinal surgery ranging from approximately 0% to 2%. The authors reviewed the quality assurance records for adult patients who underwent spinal surgery over a 10-year period (July 1, 1996 to June 30, 2006) by surgeons in the Department of Neurosurgery, University of Cincinnati College of Medicine at hospitals affiliated with the neurologic surgery residency program. Patients with new onset major neurologic deficit immediately after spinal surgery were identified. Of 11,817 adult spinal operations, 21 patients experienced new onset major neurologic deficit immediately after spinal surgery, yielding an overall incidence of 0.178%; in the cervical spine 0.293%, thoracic spine 0.488%, and lumbar/sacral spine 0.0745%. The difference in incidence between spinal regions was statistically significant (P = 0.00343). The etiology of the neurologic deficits was confirmed with reoperation and/or postoperative imaging studies: epidural hematoma in 8 patients, inadequate decompression in 5 patients, presumed vascular compromise in 4 patients, graft/cage dislodgement in 2 patients, and presumed surgical trauma in 2 patients. Placement of spinal instrumentation was performed in 12 of 21 patients (57.1%) and was associated with a significantly higher risk of new onset major neurologic deficit immediately after spinal surgery (P = 0.022). The incidence of new onset major neurologic deficit immediately after adult spinal surgery is low. Epidural hematoma and inadequate decompression were the most common etiologies in this series of patients.

Clinical manifestation and endovascular treatment of cavernous dural arteriovenous fistula

Objective To explore the clinical symptoms, performance and efficacy of endovascular treatment of cavernous sinus dural arteriovenous fistula. Method 16 cases of cavernous dural arteriovenous fistula admitted in our department from January 2006 to May 2009 and the retrospective analysis of clinical data and symptoms, vascular intervention and curative effects were analyzed. Result There were 13 patients with congestive eyes (or the merger exophthalmos), one with exophthalmos, two with temporal noise, one with subarachnoid hemorrhage. Six patients were treated by NBCA embolization through arterial approach. Immediate embolization was achieved in 3 cases after fistula occlusion. There was residual fistula in 1 case but the symptoms disappeared after 2 months. And there was residual fistula in another 2 cases, but notable improvements in symptoms were observed. 8 cases were treated through a simple approach of vein thrombosis. 2 cases in which were treated by ONYX and coil embolization and complete fistula occlusion was observed. These 2 cases were associated with postoperative oculomotor nerve palsy and outreach, the symptoms were better after 1 month. 5 cases were treated through simple ONYX embolism. 1 case was performed through combined arterial and venous approach for embolization and complete fistula occlusion was achieved. 1 cases of a small fistula was performed by carotid artery compression and the fistula was observed to be smaller after 2 month. The postoperative complications of eyes were found in 3 patients: 1 ocular and oculomotor nerve palsy, 1 diplopia and outreach nerve palsy, 1 conjunctival hyperemia and eye pain. All the complications of eyes were all alleviated. Conclusions The clinical manifestations of cavernous sinus dural arteriovenous fistula are varied. Endovascular treatment is safe and effective. Through arterial embolization approach, the possibility rate of fistula occlusion is lower than that of the intravenous approach. But the incidence of postoperative complications of eyes of arterial approach is also lower. A higher rate of fistula occlusion is observed in intravenous approach, hut it should be paid attention to the prevention of eye complications. Key words: Arteriovenous fistula; Cavernous sinus; Postoperative complication

Increased sensitivity to a nondepolarizing muscle relaxant in a patient with acquired neuromyotonia

Neuromyotonia is a disorder of hyperexcitability of the peripheral nerve. It has electromyographic features of spontaneous, continuous, irregularly occurring doublets, or multiplets of motor unit potential discharges. Neuromyotonia is characterized by both myokymic and neuromyotonic discharges. To our knowledge, this is the first report in the literature to assess the sensitivity of skeletal muscle to a nondepolarizing muscle relaxant drug, rocuronium, in a woman with acquired neuromyotonia. She had a past medical history notable for prolonged postoperative paralysis following anesthesia. The patient showed increased sensitivity to the neuromuscular effects of rocuronium. This increase in sensitivity may be explained by downregulation of acetylcholine receptors in response to chronic high agonist (acetylcholine) concentrations. If patients with neuromyotonia receive anesthesia, we recommend that smaller doses of a nondepolarizing muscle relaxant be administered, accompanied by monitoring of neuromuscular function, so as to provide optimal muscle relaxation while avoiding overdose and prolonged postoperative recovery.

Invited commentary

The bane of thoracoabdominal aortic aneurysm repair remains postoperative paralysis and paraplegia, including the delayed-onset variety. Despite study and different strategies to prevent paralysis and paraplegia, no single method of prevention has proven to be universally applicable and effective. Dr. Acher and his group have made an important observation; despite recognition of the artery of Adamkiewicz as the critical intercostal that directly supplies the spinal cord, reimplantation of this artery, or sets of additional intercostal arteries, only makes a marginal difference in rates of postoperative paraplegia when using additional spinal cord protective strategies. Thus it is likely that these other protective strategies are critical and, despite their not providing direct spinal cord reperfusion, they provide the majority of spinal cord protection during surgical procedures. As such, the modern use of adjuncts that indirectly increase spinal cord perfusion by Starling's law (tissue perfusion = input blood pressure – tissue back pressure) make sense. Maximizing systolic blood pressure increases input pressure to the tissue; removing spinal cord fluid reduces tissue back pressure; reducing cord metabolic activity reduces the need for significant input pressure. The implications for the future in which thoracic endografts will be placed with increasing frequency are clear. As endograft placement precludes revascularization of any potential critical arteries, and patients with critical arteries cannot be predicted a priori, there will be a lower limit of paralysis risk that cannot be eliminated by endograft technology with or without the use of spinal cord protective strategies. To minimize the risk of paralysis, optimization of the indirect perfusion methods must be performed. The absolute degree of protection that intercostal artery reimplantation provides is likely to be debated in the future. The importance of intercostal reimplantation may be surgeon-dependent, with increased importance of intercostal artery reimplantation for surgeons that rely on fewer additional adjuncts than used by the authors. It also remains unclear whether the benefit of intercostal artery reimplantation is limited to a specific intercostal artery, or whether any patent intercostal artery between T8 and L1 is sufficient. However, it is clear that some patients may need intercostal artery reimplantation to prevent paralysis or paraplegia, and therefore might benefit from open repair rather than an endovascular approach. Identification of this subset of patients is currently impossible. Until then, meticulous attention to details of methods that maximize spinal cord perfusion remains critical to optimizing results and minimizing the risk of adverse outcomes. A modern theory of paraplegia in the treatment of aneurysms of the thoracoabdominal aorta: An analysis of technique specific observed/expected ratios for paralysisJournal of Vascular SurgeryVol. 49Issue 5PreviewTo demonstrate that a modern theory of paraplegia prevention in thoracoabdominal aortic (TAAA) surgery is primarily non-anatomic and derives from experimentally validated interventions that prolong the ischemic tolerance, reduce reperfusion injury, and enhance the collateral perfusion of the spinal cord with or without assisted circulation. Full-Text PDF Open Archive

Vulnerability of the Femoral Nerve During Complex Anterior and Posterior Spinal Surgery

Background: Femoral nerve palsy is not a common adverse effect of lumbar spinal surgery.Objective: To report 3 unique cases of femoral nerve neuropathy due to instrumentation and positioning during complex anterior and posterior spinal surgery.Methods: Case seriesResults: All 3 patients demonstrated femoral nerve neuropathy. The first patient presented postoperatively but after 6 months, the palsy resolved. Femoral nerve malfunctioning was documented in the second and third patients intraoperatively; however, with rapid patient repositioning and removal of offending instrumentation, postoperative palsy was avoided.Conclusions: Use of motor evoked potential monitoring of the femoral nerve during surgery is vital for the prevention of future neuropathies, an avoidable complication of spinal surgery.

Microsurgical treatment for tumors in jugular foramen and its around

Objective To explore the micresurgical techniques and outcome of tumors in jugular foramen and its around. Methods Eleven patients with jugular foramen tumors were operated through suboccipital-retrosigmoid approach (2 cases), jugular foramen approach (2 cases), temporal fossa approach (4 cases) and mastoid-cervical combined approach (3 cases). Results Nine tumors were totally removed and 2 were subtotally removed. Of those cases, there were 4 neurinoma, 4 paragangliome, I meningioma, 1 mucochondrosarcoma, and 1 low-differentiated carcinoma. Postoperative complications included transient cerebrespinal fluid leak(1 case) and new lower cranial nerve injury (2 cases). All cases were followed up for mere than 8 months. The postoperative hearing was improved in 1 case, stable in 6 cases, deteriorated in 4 cases. Postoperative facial paralysis of grade Ⅱ- Ⅲ occurred in 3 of 9 patients without facial paralysis, which recovered in half a year. Of 2 patients with facial paralysis before surgery, facial function was improved in 1 case and stable in 1 case. Conclusion Proper surgical approaches and micrceurgical techniques, which were adopted according to the types, the location, and the expansion of tumors, the function of facial nerve and lower cranial nerves, and hearing level, are good for reducing complications, exposing and removing jugular foramen tumors. Key words: Jugular foramen; Skull base tumor; Micresurgery