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Purpose: To evaluate the bilateral patterns and motor function of the extralaryngeal branches (ELB) of the recurrent laryngeal nerve(RLN)., Methods: This study included 500 consecutive patients who underwent total thyroidectomy. Intraoperative nerve monitoring (IONM) was used in 230 patients. Demographic data, indications for surgery, the bilateral patterns of ELB of the RLN, electromyographic activity of the ELB, distance between the branching point to the entrance into the larynx, and the rate of postoperative morbidity were analyzed., Results: The overall rate of ELB was 27.6% (276/1000). A single trunk of the RLN on both sides was found in 269 (54%) patients, whereas ELB on both sides was observed in 45 (9%) patients. The rates of ELB on the left and right sides were 26.6 and 28.6%, respectively. Of the 89 branched nerves which were dissected using IONM, an evoked motor response was present in 100% of the anterior branches and 5.6% of the posterior branches. The mean branching distance of the RLN was significantly greater in female patients than in male patients on the left side (p = 0.031). The patterns of ELB showed no significant difference in male and female patients. The rates of postoperative transient and permanent hypoparathyroidism and unilateral RLN palsy were 21.6 and 2.8%, and 3.2 and 0.8%, respectively. The rate of RLN palsy was higher in branched nerves compared to those with a single trunk (0.75 vs 0.3%; p = 0.2)., Conclusion: Unilateral ELB of the RLN might be observed in approximately 1/4 of the patients, while bilateral branching is rare. A few number of posterior branches of the RLN can have motor function. The RLN's with ELB might have a higher risk of injury compared to those with a single trunk.

The purpose of this study was to discuss surgical approach selection, surgical procedures, and treatment strategy for preservation of the facial and lower cranial nerve function in craniocervical schwannomas surgery. Between 2002 and 2011, 44 craniocervical schwannomas were operated in Xinhua hospital of Shanghai, China by the same surgical team. The records were reviewed retrospectively regarding clinical presentation, radiographic assessment, surgical approaches selection, surgical procedures and facial and lower cranial nerve follow-up outcomes. Headache or neck pain was present in 30 patients (68.2 %) and cervical mass in 9 patients (20.5 %). Cranial nerve impairments, mainly involving the vagus nerve, were present in 19 patients (43.2 %) and hypoglossal nerve in five patients (11.4 %). 22 tumors were intra- and extracranial, 10 were intra-cranial and 12 were extra-cranial. According to the tumor region, infratemporal fossa type A approach, petrous occipital transsigmoid approach and transcervial approach were selected for tumor removal. Gross-total resection was achieved in 40 patients (90.9 %). Adjunctive radiosurgery was used in the management of residual tumor in two patients; tumor control was ultimately obtained in all cases. During follow-up period, good facial function was obtained in 42 patients (95.5 %) and complete compensation of lower cranial nerve function was achieved in all patients. The preoperative estimation of tumor in nature is of great importance in the determination of proper surgical planning of craniaocervical schwannomas. Facial nerve and lower cranial nerve function can be preserved in maximal degree by proper surgical approaches and careful operative manipulation. Initial surgical resection followed by radiosurgery may be an effective option for some special patients.

Objective: To study the anatomic characteristics of recurrent laryngeal nerve during thyroid surgery., Method: A retrospective review of surgical data of 307 patients undertook thyroid surgery was conducted., Result: Total 342 recurrent laryngeal nerves were identified during the surgery(184 on the right side, left 158). 215 (62.9%) nerves were deep to the inferior thyroid artery, 106(31.0%)were superficial to the artery, 21(7.5%) were between the arterial branches. A nerve bifurcation was found in 203(59.4%). None of nerve bifurcation was found in 136(39.8%). 3(0.9%)were confirmed to hold non-recurrent laryngeal nerves during operations. No patient showed permanent laryngeal recurrent nerve paralysis postoperatively., Conclusion: The careful dissection and protection of the recurrent laryngeal nerve was an effective method to prevent its injury during thyroid surgery.

Purpose: Cornea confocal microscopy is emerging as a clinical tool to evaluate the development and progression of diabetic neuropathy. The purpose of these studies was to characterize the early changes in corneal sensitivity and innervation in a rat model of type 1 diabetes in relation to standard peripheral neuropathy endpoints and to assess the effect of Ilepatril, a vasopeptidase inhibitor which blocks angiotensin converting enzyme and neutral endopeptidase, on these endpoints., Methods: Streptozotocin-diabetic rats 8 weeks duration were treated with or without Ilepatril for the last 6 weeks of the experimental period. Afterwards, standard diabetic neuropathy endpoints, subbasal corneal nerves and innervation of the epithelium, corneal sensitivity using a Cochet-Bonnet esthesiometer, and vascular reactivity of the posterior ciliary artery were examined., Results: Diabetes caused a decrease in nerve conduction velocity, thermal hypoalgesia, and a reduction in intraepidermal nerve fiber profiles. In the cornea there was a decrease in corneal nerve fibers innervating the epithelium and corneal sensitivity, but subbasal corneal nerve fibers was not changed. Vascular relaxation in response to acetylcholine was decreased in the posterior ciliary artery. These defects were partially to completely prevented by Ilepatril treatment., Conclusions: These studies suggest that in type 1 diabetic rats decreased innervation of the cornea epithelium occurs early in diabetes and prior to a detectable decrease in subbasal corneal nerves and that these and other diabetic neuropathy-related defects can be partially to completely prevented by a vasopeptidase inhibitor.

Introduction: Patients with locally advanced nasopharyngeal carcinoma (NPC) commonly present with cranial nerve (CN) involvement, which can cause significant morbidity. We aimed to characterise the pattern of involvement and outcomes of these patients, as well as determine if these differed according to the mode of diagnosis., Methods: Patients were included if they had non-distant metastatic NPC, presented with CN involvement and completed radiotherapy treatment between 2002 and 2008. The clinical response was categorised as complete response, partial response, stable or progressive disease. The radiological response was assessed using the Response Evaluation Criteria in Solid Tumors criteria. The loco-regional control and disease-free survival rates were estimated with the Kaplan-Meier method., Results: Forty-seven patients fulfilled the inclusion criteria. CN lesions were diagnosed on clinical examination in 15% of patients, radiologically in 40% and both clinically and radiologically in 45% of patients. A complete or partial response of the CN lesions was seen clinically in 82% and radiologically in 95% of patients. The 3-year local relapse free survival was 64.3%, distant metastasis-free survival was 46.1% and overall survival was 82.8%. There were no differences in outcomes between patients with clinically versus radiologically detected CN lesions., Conclusion: Most of these patients are likely to undergo clinical and/or radiological resolution of the nerve lesions following chemoradiotherapy, but the outcome was not determined by the mode of diagnosis (radiological or clinical)., (© 2012 The Authors. Journal of Medical Imaging and Radiation Oncology © 2012 The Royal Australian and New Zealand College of Radiologists.)

Objective: The authors show their experience with brainstem cavernomas, comparing their data with the ones of a literature review., Methods: From 1998 to 2009, 13 patients harboring brainstem cavernomas underwent surgical resection. All plain films, medical records and images were reviewed in order to sample the most important data regarding epidemiology, clinical picture, radiological findings and surgical outcomes, as well as main complications., Results: The mean age was 42.4 years (ranging from 19 to 70). No predominant gender: male-to-female ratio, 6:7. Pontine cases were more frequent. Magnetic resonance imaging was used as the imaging method to diagnose cavernomas in all cases. The mean follow-up was 71.3 months (range of 1 to 138 months). Clinical presentation was a single cranial nerve deficit, VIII paresis, tinnitus and hearing loss (69.2%). All 13 patients underwent resection of the symptomatic brainstem cavernoma. Complete removal was accomplished in 11 patients. Morbidity and mortality were 15.3 and 7.6%, respectively., Conclusions: Cavernomas can be resected safely with optimal surgical approach (feasible entry zone) and microsurgical techniques, and the goal is to remove all lesions with no cranial nerves impairment.

To improve locoregional tumor control and survival in patients with locally advanced head and neck cancer (HNC), therapy is intensified using altered fractionation radiation therapy or concomitant chemotherapy. However, intensification of therapy has been associated with increased acute and late toxic effects. The application of advanced radiation techniques, such as 3D conformal radiation therapy and intensity-modulated radiation therapy, is expected to improve the therapeutic index of radiation therapy for HNC by limiting the dose to critical organs and possibly increasing locoregional tumor control. To date, Review articles have covered the prevention and treatment of radiation-induced xerostomia and dysphagia, but few articles have discussed the prevention of hearing loss, brain necrosis, cranial nerve palsy and osteoradionecrosis of the mandible, which are all potential complications of radiation therapy for HNC. This Review describes the efforts to prevent therapy-related complications by presenting the state of the art evidence regarding advanced radiation therapy technology as an organ-sparing approach.

Development of less invasive imaging studies, such as magnetic resonance angiography, has increased the chances that unruptured cerebral aneurysms are found. The rupture risk of "symptomatic" aneurysms is higher than for "asymptomatic" aneurysms; so "symptomatic" aneurysms are more often surgically treated. Many reviews examine "asymptomatic" unruptured cerebral aneurysms, but few evaluate "symptomatic" aneurysms. The author has treated many patients with symptomatic unruptured cerebral aneurysms and found that improved cranial nerve signs can be expected if the surgical treatment is performed before the symptoms become irreversible; the critical period is approximately 3 months. It is important to suppress the pulsation of the aneurysms compressing the cranial nerves; both a clipping procedure and endovascular coiling are effective. Cranial nerve signs are more commonly the symptoms of unruptured cerebral aneurysms, but large to giant aneurysms can also be the causes of hemiparesis, hydrocephalus, epilepsy, or even cerebral infarction. This review summarizes the features and surgical outcome of symptomatic unruptured cerebral aneurysms.

Purpose: To reveal the influence of retrobulbar capsaicin treatment on rats' eyes and to test the protective effects of PEDF, a known neurotrophic and antiangiogenic substance, against neurotrophic keratouveitis., Methods: A single retrobulbar injection of capsaicin (50 mg/kg) was performed in young rats, and the effect of subsequent retrobulbar injections of PEDF 3.2 or 6.4 microg was recorded. Tear fluid alterations were evaluated with the Schirmer test and corneal alterations with slit lamp biomicroscopy. Histopathologic alterations were studied with light and electron microscopy. The number of leukocytes (myeloid cells) in the anterior and posterior chambers, peripheral retina, and vitreous were quantitatively evaluated., Results: Reduced tear secretion was found in capsaicin-treated rats compared with the control, but this effect was significantly attenuated by PEDF. Corneal ulceration developed and was followed by scar formation and neovascularization in the capsaicin-treated, and it was also significantly attenuated by PEDF treatment. Leukocyte infiltration of the anterior and posterior chambers, as well as the peripheral retina and vitreous, was also observed in capsaicin-treated eyes and was significantly reduced by PEDF treatment. The protective effects of PEDF were dose dependent for each parameter, even if the treatment was initiated at day 14 after the challenge., Conclusions: PEDF accelerated the recovery of tear secretion and also prevented capsaicin-induced neurotrophic keratouveitis and peripheral vitreoretinal inflammation. These effects of PEDF, described herein for the first time, may have a clinical application in inflammatory and neovascular diseases of the eye.

Transarterial embolization in the external carotid artery (ECA) territory has a major role in the endovascular management of epistaxis, skull base tumors, and dural arteriovenous fistulas. Knowledge of the potential anastomotic routes, identification of the cranial nerve supply from the ECA, and the proper choice of embolic material are crucial to help the interventionalist avoid neurologic complications during the procedure. Three regions along the skull base constitute potential anastomotic routes between the extracranial and intracranial arteries: the orbital, the petrocavernous, and the upper cervical regions. Branches of the internal maxillary artery have anastomoses with the ophthalmic artery and petrocavernous internal carotid artery (ICA), whereas the branches of the ascending pharyngeal artery are connected to the petrocavernous ICA. Branches of both the ascending pharyngeal artery and the occipital artery have anastomoses with the vertebral artery. To avoid cranial nerve palsy, one must have knowledge of the supply to the lower cranial nerves: The petrous branch of the middle meningeal artery and the stylomastoid branch of the posterior auricular artery form the facial arcade as the major supply to the facial nerve, and the neuromeningeal trunk of the ascending pharyngeal artery supplies the lower cranial nerves (CN IX-XII).

Introduction: The relationship between target volume and adverse radiation effects (AREs) at low prescription doses requires elucidation. The development of AREs in three series of patients treated in the Gamma Knife is analysed in relation to prescription dose and target volume., Materials and Methods: There were three groups. In group 1, there were of 275 patients with meningiomas; in group 2, 132 patients with vestibular schwannomas; and in group 3, 107 patients with arteriovenous malformations (AVMs). The minimum follow-up for each group was more than 24 months. All patients were followed up at six monthly intervals. The patients with tumours received a prescription dose of 12 Gy, which was varied to protect normal structures but not in relation to tumour volume per se. The desired AVM prescription dose was 25 Gy, but this was also reduced to protect normal structures and to keep the total dose within certain pre-defined limits. All AREs refer to intra-parenchymal increased perilesional T2 signal on MR irrespective of clinical correlation., Results: There was no relationship between tumour volume and the development of ARE in the tumour groups. There was a highly significant relationship between target volume and the development of ARE for the AVMs with their much higher dose. Radiation-induced clinical trigeminal and facial nerve deficits with both vestibular schwannomas and meningiomas were always associated with an increased T2 signal in the neighbouring brainstem parenchyma., Conclusions: The relationship between target volume and the risk of adverse radiation effects may not apply with lower prescription doses. Individual radiosensitivity may explain why a minority suffer AREs unrelated to target volume. It is possible that radiation-induced brainstem parenchymal damage with concomitant cranial nerve deficits may be commoner after radiosurgery than is usually thought. If tumour control with lower doses is adequate, radiosurgery could be safely considered for larger targets associated with a high risk from microsurgery.

Background and Purpose: Internal carotid artery (ICA) aneurysms may present with cranial nerve dysfunction. Therapeutic ICA occlusion, when tolerated, is an effective treatment resulting in improvement or cure of symptoms in most patients. When ICA occlusion is not tolerated, selective endovascular aneurysm occlusion can be considered. We compare recovery of cranial nerve dysfunction in patients treated with selective coil occlusion and with therapeutic ICA occlusion., Materials and Methods: In 16 patients with 17 large or giant (11-45 mm) unruptured ICA aneurysms presenting with dysfunction of cranial nerves (CN) II, III, IV, or VI, selective coil occlusion was performed. From a cohort of 39 patients with ICA aneurysms treated with ICA occlusion and long-term follow-up, we selected 31 patients with aneurysms presenting with cranial nerve dysfunction. Clinical recovery at follow-up from oculomotor dysfunction and visual symptoms was compared for both treatment modalities., Results: Of 17 aneurysms treated with selective coiling, symptoms of cranial nerve dysfunction resolved in 3, improved in 10, and remained unchanged in 4. In 9 of 17 patients, additional coiling during follow-up was required. Of 31 aneurysms treated with carotid artery occlusion, cranial nerve dysfunction resolved in 19, improved in 9, and remained unchanged in 3. These differences were not significant. There were no complications of treatment., Conclusion: Recovery of ICA aneurysm-induced cranial nerve dysfunction occurs in most patients, both after ICA occlusion and after selective coiling. In patients who cannot tolerate ICA occlusion, selective aneurysmal occlusion with coils is a valuable alternative.

Purpose: To review the pathophysiology of LASIK-associated dry eye conditions and provide insights into prophylaxis to decrease the incidence of dry eye after LASIK and to treat the condition when it occurs., Methods: A review of the literature was performed on LASIK-associated dry eye and the experience of the authors was summarized., Results: LASIK has a neurotrophic effect on the cornea, along with other changes in corneal shape, that affect tear dynamics causing ocular surface desiccation. Dry eye is one of the most common complications of LASIK surgery. Symptoms of dryness may occur in more than 50% of patients, with other complications such as fluctuating vision, decreased best spectacle-corrected visiual acuity, and severe discomfort occurring in approximately 10% of patients. Preoperative dry eye condition is a major risk factor for more severe dry eye after surgery and should be identified prior to surgery. Optimization with artificial tears, nutrition supplementation, punctal occlusion, and topical cyclosporine A in patients with symptoms or signs of dry eye prior to LASIK decreases the incidence of more bothersome symptoms following surgery. Patients with LASIK-induced neurotrophic epitheliopathy often respond to topical cyclosporine A treatment, which treats the underlying inflammation and may benefit nerve regeneration., Conclusions: LASIK-induced dry eye and neurotrophic epitheliopathy are common complications of LASIK surgery. Optimization of the ocular surface prior to surgery decreases the incidence and severity of postoperative symptoms of the condition.

Background: This work aimed to study the outcome of endovascular (coiling and balloon occlusion) treatment in patients with aneurysmal mass effect (ophthalmoplegia due to third, fourth, or sixth CN paresis) and to compare it with the outcome of clipping (from the international literature). We looked at the outcome of endovascular treatment of CNP (third, fourth, and sixth) due to aneurysmal mass effect (PcomA aneurysms and intracavernous carotid aneurysms)., Methods: Between January 1999 and December 2004, 820 patients presented with aneurysmal SAH and/or mass effect. Eleven of these patients (1%) presented with third, and/or fourth, and/or sixth nerve dysfunctions and underwent endovascular treatment. The degree of the ophthalmoplegia was recorded at presentation, 2 months, 6 months, and yearly intervals thereafter. We correlated recovery of CNP to SAH, duration of the symptoms, degree of CNP, type of CNP, microvascular risks (age, diabetes mellitus, hypertension, and smoking), aneurysm size, and degree of coiling or balloon occlusion., Results: The study showed a favorable outcome of endovascular treatment in the majority of patients. Resolution of CN dysfunctions occurred in 7 (64%) of 11 patients. The late follow-up showed that all the 7 patients are resuming normal life activities. This compares favorably to the results after clipping in [Leivo, Hemesniemi, Luukkonen, & Vapalahti, 1996] (41%). Presentation with SAH and isolated third CNP correlated with a better resolution of CNP (P < .05)., Conclusion: Although mass effect remains after endovascular packing, CNP improves comparably to the recovery observed after surgical clipping. It seems likely that the decrease in aneurysmal pulsatility is responsible for the improvement of the CNP. The relatively atraumatic approach associated with endovascular management explains the favorable results. All previous reports assessed the outcome of only the third CNP after endovascular treatment in a very limited number of cases. To the best of our knowledge, this is the first study to assess the outcome of various CNP after endovascular treatment.

Objective: We report our experience gaining access to the cavernous sinus via transfacial catheterization of the superior ophthalmic vein through the angular or retromandibular vein. We evaluate the viability of this approach as a safe and convenient alternative pathway for transvenous embolization of the cavernous sinus., Methods: This is a retrospective study of 98 patients with symptomatic dural carotid-cavernous fistulae from two major regional hospitals in Hong Kong. All 98 patients presented with one or more ocular symptoms. Seventy-four transvenous embolization procedures were performed on 71 patients. Transvenous access to the cavernous sinus was attempted through various pathways, one by one, until the cavernous sinus was successfully catheterized., Results: The overall technical success rate of transvenous embolization of dural carotid-cavernous fistulae in our study was 64 out of 74 patients (86.5%). Had we not used the technique of transfacial catheterization, the technical success rate would have been 53 out of 74 patients (71.6%). After adoption of the transfacial approach, the technical success rate of transvenous embolization became 64 out of 64 patients (100%). Residual symptoms occurred in eight patients. Two patients developed transient VIth cranial nerve palsy after transvenous embolization for 1 and 2 months, respectively. Otherwise, there were no complications., Conclusion: Transfacial catheterization through the superior ophthalmic vein is a safe and effective approach and provides a convenient alternative pathway for transvenous embolization of dural carotid-cavernous fistulae when cannulation of the inferior petrosal sinus is not successful, thereby increasing the technical success rate.

Neurotologic and skull base surgery involves working around important neurovascular and neurotologic structures and can incur unwarranted complications. Knowledge of surgical anatomy, good preoperative planning, intraoperative monitoring, and excellent microsurgical technique contribute to minimizing and avoiding complications. In the event of a complication, however, the neurotologic surgeon should be prepared to manage it. In this article, the authors focus on the management of complications encountered in neurotologic skull base surgery, including hemorrhage, stroke, cerebrospinal fluid leak, extraocular motility deficits, facial paralysis, hearing loss, dizziness, lower cranial nerve palsies, and postoperative headache.

Objective: The purpose of this study was to evaluate aneurysm size and clinical symptoms midterm after therapeutic carotid artery occlusion in 39 patients with large or giant carotid artery aneurysms., Methods: Between January 1996 and August 2004, 39 patients with large or giant carotid artery aneurysms were treated with therapeutic carotid artery occlusion and had clinical and magnetic resonance imaging follow-up of at least 3 months (mean, 35.9 mo; median, 29 mo; range, 3-107 mo; 117 patient-yr). Initial clinical presentation was mass effect caused by the aneurysm in 32 (82%) of the 39 patients. Three patients presented with subarachnoid hemorrhage and one presented with epistaxis; two aneurysms were an incidental finding and one was additional to another ruptured aneurysm., Results: There were no early or late complications of therapeutic carotid artery occlusion. All aneurysms seemed to have thrombosed completely after carotid artery occlusion as observed on early and late magnetic resonance imaging and magnetic resonance angiographic follow-up studies. At the time of the most recent magnetic resonance imaging follow-up study, 29 (74%) of the 39 aneurysms involuted totally, two aneurysms decreased to 25% of the original diameter, two aneurysms decreased to 50%, and five aneurysms decreased to 75%. Two aneurysms remained unchanged in size after 49 and 58 months, respectively. At the most recent clinical follow-up evaluation, symptoms of mass effect were cured in 19 (60%), improved in 10 (31%), and remained unchanged in three (9%) of the 32 patients., Conclusion: Therapeutic carotid artery occlusion was a simple, safe, and effective treatment for large and giant carotid artery aneurysms. Almost all aneurysms involute completely or substantially decrease in size. Alleviation of symptoms of mass effect was achieved in most patients.

The anatomical course of the external branch of the superior laryngeal nerve (EBSLN) is variable, and a consistent approach to its preservation during thyroid surgery is needed to reduce risk of post-operative voice impairment. Despite agreement that careful dissection in the region of the superior thyroid pole is required, there is no accepted 'best' approach, nor any universal acknowledgement that location of the EBSLN is actually necessary. The popular cernea classification of EBSLN has limitations, including its decreased reliability with increased thyroid size and its irrelevance in cases of 'buried' variants. * Recent work has identified factors such as ethnicity and stature in the prevalence of EBSLN variants. Consistent approaches to the post-operative detection of EBSLN injury are needed to build an accurate picture of the incidence of surgical nerve injury. Then a standardised approach to EBSLN preservation may emerge.

Purpose: Although submandibular sialadenectomy with a minimal incision improves overall cosmetic outcomes, visualization of the surgical field exposure is relatively limited as compared with that in the conventional procedure. To overcome this limitation, we applied the endoscope system to submandibular sialadenectomy. The aim of this study was to evaluate the technical feasibility and potential role of our endoscope-assisted submandibular sialadenectomy (EASS)., Materials and Methods: We performed EASS on 5 patients, 3 of whom had intraparenchymal sialolithiasis and 2 of whom had pleomorphic adenomas. The dissection was carried out by bipolar dissection with a 4-mm nasal endoscope system., Results: The procedure achieved successful results for all 5 patients except for 1 who had severe adhesion to the adjacent tissues; this patient suffered from postoperative lingual nerve paresthesia. All the patients achieved good cosmetic outcomes., Conclusions: An EASS with bipolar dissection is technically feasible and secures a better surgical view through a minimal incision. However, for patients with severe adhesion to the adjacent tissues, conversion to the wide-open procedure would be safer.

Objective: Several studies have reported on approaches to increase exposure of the distal cervical internal carotid artery (ICA), but these studies have neither systematically addressed the anatomic aspects nor quantified the additional exposure of each maneuver. We describe surgical steps to expose the ICA region, quantify the additional exposure of each operative step, and discuss ways to minimize surgical morbidity., Methods: The ICA was exposed in 10 formalin-fixed cadaveric heads using the following four steps: 1) anterior sternocleidomastoid approach, 2) retroparotid dissection and division of the digastric muscle, 3) section of the styloid apparatus, and 4) mandibulotomy. After completion of each step, the most distal level of ICA exposure was marked with a hemoclip and segment lengths were measured between each clip., Results: Sectioning of the digastric muscle and sectioning of the styloid apparatus provided the most significant exposure of the ICA (14.15 and 15.08 mm, respectively) with minimal risks. Mandibulotomy added 10.20 mm in length and 20.65 degrees in width, but is a maneuver that must be weighed against the heightened risk of morbidity., Conclusion: Surgical exposure of the distal cervical ICA is associated with relatively high morbidity that increases with higher levels of exposure. Staged maneuvers have been shown to increase ICA exposure, especially in our systematic approach. The number of steps required varies depending on the level of lesion. Complete understanding of the surgical anatomy is essential to minimize surgical morbidity and to develop surgical expertise.

Background: The anticonvulsant valproic acid (sodium valproate, Depacon) acts as a neuroprotectant in rodents, but has never been tested in larger animals. We used valproate in our canine model of hypothermic circulatory arrest to evaluate its neuroprotective benefit in complex cardiac surgical cases., Methods: Thirteen dogs pretreated with valproate before 2 hours of hypothermic circulatory arrest survived for 24 hours (n = 7) or 72 hours (n = 6). Thirteen control animals (placebo only) also survived for 24 hours (n = 7) or 72 hours (n = 6) after hypothermic circulatory arrest. Blinded clinical neurologic evaluation was performed daily until sacrifice using the Pittsburgh Canine Neurologic Scoring System. Brains were harvested for blinded histopathologic analysis by a neuropathologist to determine the extent of apoptosis and necrosis in 11 brain regions (Total Brain Cell Death Score: 0 = normal, 99 = extensive neuronal death in all regions). Quantification of N-acetyl-aspartate, an established marker for brain injury, was performed with mass spectrometry., Results: Valproate dogs scored significantly better than control animals on clinical neurologic evaluation. Histopathologic examination revealed that valproate animals demonstrated less neuronal damage (by Total Brain Cell Death Score) than control animals at both 24 hours (16.4 versus 11.4; p = 0.03) and 72 hours (21.7 versus 17.7; p = 0.07). At 72 hours, the entorhinal cortex, an area involved with learning and memory, was significantly protected in valproate dogs (p < 0.05). Furthermore, the cortex, hippocampus, and cerebellum demonstrated preservation of near-normal N-acetyl-aspartate levels after valproate pretreatment., Conclusions: These data demonstrate clinical, histologic, and biochemical improvements in dogs pretreated with valproate before hypothermic circulatory arrest. This commonly used drug may offer a promising new approach to neuroprotection during cardiac surgery.

Objective: To describe functional and reconstructive results after revision lateral skull base surgery with comparison of benign and malignant lesions., Study Design: Retrospective case review., Setting: Tertiary referral center., Patients: All patients undergoing revision surgery for benign and malignant lateral skull base tumors., Interventions: Surgical resection of recurrent lateral skull base tumors and reconstruction of resulting defects., Main Outcome Measures: Cranial nerve function postoperative complications., Results: Forty operations for recurrent lateral skull base tumors occurred between January 1, 1987, and December 31, 2003, with follow-up of at least 1 year. Thirty-three operations were for benign lesions, 27 of which were glomus tumors. Seven operations were for malignant tumors. Fifty-eight percent of patients had preoperative cranial nerve deficits (66% of benign tumors and 14% of malignancies). The most common preoperative deficit occurred in the Xth cranial nerve. Postoperative cranial nerve deficits were seen in 95% of patients and multiple nerve deficits were seen in 75%. The most common postoperative deficits were observed in the IXth and Xth cranial nerves. Thirty-one patients had one previous procedure, six had two previous procedures, and three had three previous procedures. Abdominal fat and temporoparietal fascia were the most common reconstruction materials. There was one case of meningitis, two cerebrospinal fluid leaks, and one pseudomeningocele. There was one recurrent adenoid cystic tumor resulting in death and two partially resected glomus tumors. Subsequent procedures are discussed., Conclusion: Postoperative cranial deficits are more common after revision skull base surgery than after primary surgery. Complete resection without recurrence can be expected for revision skull base surgery. Modern reconstruction techniques reduce major postoperative complications and morbidity from cranial nerve deficits.

Background: The SELH/Bc mouse inbred strain, with a high frequency of nonsyndromic, genetically-multifactorial exencephaly, is a model for human cranial neural tube defects (NTDs). Maternal diet affects risk of human NTDs., Methods: Exencephaly frequencies in SELH/Bc embryos were compared in 8 studies in which dams were fed alternative commercial Purina diets (5015 and 5001) or semisynthetic diets, and in several studies in which maternal diet was supplemented with a specific nutrient, either in drinking water or food before and during pregnancy, or by intraperitoneal injection on E7 and/or E8., Results: The exencephaly frequency in SELH/Bc embryos was 2- to 8-fold higher when the dams were fed Purina 5015 (averaging 23% exencephaly) or a semisynthetic diet modeled on Purina 5015 (averaging 28%) or NIH-31 standard diet (23%), compared with Purina 5001 (averaging 7%). The exencephaly frequency remained high (41%) on a semisynthetic diet modeled on Purina 5001. The exencephaly frequency was not reduced significantly by maternal supplementation with folic acid, nor with each of zinc, methionine, niacin, brewers' yeast, riboflavin, vitamin B12, or inositol. Nor was it reduced by maternal diets with supplemental methyl donors and cofactors or with reduced fat., Conclusions: The frequency of exencephaly in SELH/Bc embryos is strongly influenced by a specific unidentified aspect of the commercial ration Purina 5001 that prevents 55-85% of exencephaly in SELH/Bc embryos, when directly compared with an alternative commercial ration Purina 5015 or its semisynthetic mimic. This strong maternal diet effect on NTD frequency may point to novel nutritional approaches to prevention of human NTDs., (Copyright 2005 Wiley-Liss, Inc.)

The authors review the recent international literature relating to approximately 36,800 cases of thyroid surgery, analysing the complications associated with total thyroidectomy versus partial resection of the thyroid, with a view to drawing up lines of conduct in terms of indications for surgery of benign disease and suggestions on surgical technique to reduce complications such as recurrent laryngeal nerve injuries (transient and definitive), hypocalcaemia (transient and definitive) and superior laryngeal nerve injuries.

Purpose: To assess the relationship of aspirin use and ischemic cranial nerve palsies among patients with diabetes mellitus and hypertension., Methods: This retrospective case-control study involved 100 patients with ischemic cranial nerve palsies in association with diabetes, hypertension, or both (palsy cases) and 163 age-matched and sex-matched patients with diabetes, hypertension, or both but without ischemic cranial nerve palsies (nonpalsy control subjects). Comparisons were made with respect to duration of diabetes, dose and duration of aspirin use, dose and duration of tobacco use, and presence of cardiac or cerebrovascular disease., Results: There were 20 oculomotor, 33 trochlear, 37 abducens, and 10 facial nerve palsy cases. The median duration of diabetes was 6 years for cases and 7 years for control subjects. There were 34 cases (34%) who had used aspirin for a mean duration of 5.5 years before the onset of the cranial nerve palsy and 49 control subjects (30.1%) who had used aspirin for a mean duration of 4.3 years. There were no significant differences between cases and control subjects for duration of diabetes (P =.94); aspirin use (P =.51), duration (P =.50), and dosage (P =.89); tobacco use (P =.73) and consumption (P =.45); and proportion of cardiac disease (P =.17). Cerebrovascular disease was significantly less common among palsy cases than nonpalsy control subjects (P<.001). There was no significant difference in the odds of a patient having cranial nerve palsy in the aspirin group compared with the nonaspirin group (odds ratio, 1.12; 95% confidence interval, 0.70-2.04)., Conclusion: Aspirin use was not associated with a reduced rate of ischemic third, fourth, sixth, and seventh nerve palsies among patients with diabetes mellitus and hypertension. Aspirin appears to be ineffective in preventing ischemic third, fourth, sixth, and seventh cranial nerve palsies. Patients with ischemic cranial nerve palsy have a significantly lower rate of strokes and transient ischemic attacks than patients who have diabetes or hypertension but who do not have a history of cranial nerve palsy.

Purpose: To determine whether tumor control can be maintained, and cranial nerve complications decreased by reducing the radiosurgical dose to acoustic neuromas., Methods and Materials: Forty-two consecutive patients with acoustic neuromas were treated prospectively using an initial standard-dose protocol in which the tumor-margin dose (50% isodose) was 20, 18, and 16 Gy for tumor diameters < or =2 cm, 2.1-3 cm, and 3.1-4 cm, respectively. After analysis of tumor control and complications, the next 40 patients were treated using a reduced-dose protocol in which the tumor-margin dose was 16, 14, and 12 Gy for tumor volumes < or =4.2 cm3, 4.2-14.1 cm3, and > or =14.1 cm3, respectively., Results: Median follow-up was 2.3 years (range 0.1-6) for 80 of 82 patients. The actuarial incidence (Kaplan-Meier) of facial neuropathy at 2 years was 38% (95% confidence interval [CI], 23-53%) for the standard-dose protocol and 8% (95% CI, 0-17%) for the reduced-dose protocol (p = 0.006). Univariate analysis revealed an association between risk of facial neuropathy and use of CT planning, higher radiosurgical dose, and neurofibromatosis, type 2. Multivariate analysis revealed that the only factor associated with increased risk of post-treatment facial neuropathy was a tumor margin dose > or =18 Gy. The incidence of trigeminal neuropathy at 2 years was 29% (95% CI, 15-43%) for the standard-dose protocol and 15% (95% CI, 3-27%) for the reduced-dose protocol (p = 0.17). Univariate analysis revealed an association between maximal tumor diameter and increased risk of trigeminal neuropathy; multivariate analysis revealed no additional statistically significant associations between tumor and dosimetric and patient characteristics and risk of trigeminal neuropathy. Two tumors in the standard-dose protocol required salvage surgery for progression. To date, no tumor in the reduced-dose protocol has shown progression., Conclusion: Our analysis suggests that a tumor margin dose of > or =18 Gy is the most significant risk factor for facial nerve complications after acoustic neuroma radiosurgery. Patients receiving a minimal tumor dose of < or =16 Gy are at significantly lower risk for permanent facial neuropathy after radiosurgery. Longer follow-up is required before definitive conclusions can be made about the ultimate rate of tumor control using reduced radiosurgical doses.

In this retrospective study, oncologic and functional results of 24 patients treated for glomus jugulare tumor stages C and D are reported. The surgical approach used was a combined transmastoid-transcervical approach, which was modified according to individual tumor growth. As needed, this was combined with a transtemporal or retrosigmoid approach. Complete tumor removal resulted in a cure rate of 100%. Surgically induced cranial nerve palsies developed in 38% of the patients. In 54% of cases it was possible to retain middle ear function. Seven patients had incomplete tumor removal requiring postoperative irradiation, with tumor progression occurring in 2 patients. Radical tumor removal was modified by efforts to reduce mutilating resections. These results show that individually tailored and combined multidirectional surgical approaches can allow total tumor removal to be performed with lower morbidity.

Objective: To identify the actual benefits and persisting problems in treating vestibular schwannomas by the suboccipital approach, the results and complications in a consecutive series of 1000 tumors surgically treated by the senior author were analyzed and compared with experiences involving other treatment modalities., Methods: Pre- and postoperative clinical statuses were determined and radiological and surgical findings were collected and evaluated in a large database for 962 patients undergoing 1000 vestibular schwannoma operations at Nordstadt's neurosurgical department from 1978 to 1993., Results: By the suboccipital transmeatal approach, 979 tumors were completely removed; in 21 cases, deliberate partial removal was performed either in severely ill patients for decompression of the brain stem or in an attempt to preserve hearing in the last hearing ear. Anatomic preservation of the facial nerve was achieved in 93% of the patients and of the cochlear nerve in 68%. Major neurological complications included 1 case of tetraparesis, 10 cases of hemiparesis, and caudal cranial nerve palsies in 5.5% of the cases. Surgical complications included hematomas in 2.2% of the cases, cerebrospinal fluid fistulas in 9.2%, hydrocephalus in 2.3%, bacterial meningitis in 1.2%, and wound revisions in 1.1%. There were 11 deaths occurring at 2 to 69 days postoperatively (1.1%). The techniques that were developed for avoidance of complications are reported. The analysis identifies preexisting severe general and/or neurological morbidity, cystic tumor formation, and major caudal cranial nerve deficits as relevant risk factors., Conclusion: The current treatment options of complete tumor resection with ongoing reduction of morbidity are well fulfilled by the suboccipital approach. By careful patient selection, the mortality rate should be further reduced to below 1%.

In this retrospective study, oncologic and functional results of 46 patients treated for glomus jugulare tumor are reported. The standard surgical approach was the combined transmastoid-transcervical approach, modified according to the individual tumor growth, and eventually combined with a transtemporal or a suboccipital approach. Complete tumor removal resulted in a cure rate of 90%. New-onset cranial nerve palsies developed in less than 22% of patients. In 54% of cases it was possible to retain middle ear function. From a total of 12 patients with incomplete tumor removal and postoperative irradiation, progressive tumor growth was noted in 4 patients, and was controlled by salvage irradiation or surgery. Radical tumor removal by ablative surgery can be modified by efforts to reduce multilating resections. In their place, individually tailored and combined multidirectional surgical approaches may allow total tumor removal with lower morbidity.

Permanent neurologic damage after an inferior dental nerve block is reported. Clinical manifestations included hemisensory syndrome, facial nerve palsy, hearing impairment, and ataxia. Possible mechanisms and preventive measures are discussed.

Neurological consequences of extractions of the third inferior molar can be severe. Progress in imaging techniques has made it possible to identify molars << at risk >>. Extraction by wear without removal of the apex is proposed as a means of avoiding damage to the alveolar nerve. If no surgical prophylaxy is used the risk is major sequellae: painful anaesthesia of the area involved. There is no really effective treatment for such sequellae, creating persistent psychological problems throughout life.

Objective: To assess those factors associated with and predictive of cranial nerve preservation after stereotactic radiosurgery in patients with small acoustic tumors identified by magnetic resonance imaging., Design: We performed a retrospective analysis of our experience with 31 patients with preserved hearing and acoustic tumors measuring 10 mm or smaller (pons-to-petrous dimension). All patients underwent clinical and audiologic evaluations varying from 6 to 48 months (mean, 20 months) after stereotactic radiosurgery performed with use of the 201 source cobalt 60 gamma unit., Results: Stabilization or reduction in tumor volume was achieved in 29 of 31 patients. One patient required delayed microsurgical resection. Useful hearing (pure tone average < or = 50 dB and speech discrimination score > or = 50%) preservation was achieved in 10 of 10 patients immediately postoperatively, eight of 10 patients at 6 months, six of 10 patients at 1 year, and five of 10 at 2 years. Preservation of some measurable hearing was possible in all patients immediately after radiosurgery, in 84% and in more than half of patients at 2 years. Preoperative facial nerve function was preserved in 19 of 20 patients at 2 years after radiosurgery. All patients returned to their preoperative employment status within 2 to 5 days after radiosurgery., Conclusion: Stereotactic radiosurgery performed with current technology (multiple radiation isocenters and magnetic resonance imaging guidance) is a safe and effective management strategy for patients with small acoustic tumors. The risk of facial and trigeminal neuropathy after gamma knife radiosurgery is low, and useful hearing can be preserved in up to 50% of patients with useful preoperative hearing. Stereotactic radiosurgery is a valuable alternative strategy to surgical removal for many patients with newly diagnosed small acoustic tumors.

Between March 1966 and September 1992, 1400 acoustic neuromas were treated in Paris, France, by surgical excision. The findings over the last 7 years are presented. The translabyrinthine approach has been used in more than 85% of cases. Where hearing preservation is attempted, the middle fossa approach has been adapted for intracanilicular tumors and the retrosigmoid approach for small tumors extending into the cerebellopontine angle, in which the fundus of the internal meatus is free of tumor. The main goal is to achieve a grade I or II result in facial function within 1 month of surgery. Results improved during 1991 after the introduction of continuous facial nerve monitoring and the use of the Beaver mini-blade for dissection of tumor from nerve. With these techniques, facial function of grade I or II at 1 month improved from 20% to 52% for large tumors (larger than 3 cm), from 42% to 81% for medium tumors (2 to 3 cm). and from 70% to 92% for small tumors (up to and including 2 cm extracanalicular). The facial nerve was at greater risk using the retrosigmoid or middle fossa approaches than by the translabyrinthine route. Since 1985, success in hearing preservation has changed little, with useful hearing being preserved in 38.2% of cases operated on by means of the retrosigmoid route and a 36.4% of cases after the middle fossa approach. In older patients with good hearing and small tumors, observation with periodic MRI scanning is recommended. Despite earlier diagnosis, the number of patients suitable for hearing preservation surgery remains very limited and careful selection is required. Trigeminal nerve signs were present in 20% of cases preoperatively, in 10% postoperatively, and recovered spontaneously. Palsies of the other cranial nerves after surgery were much rarer and were as follows: sixth nerve (abducens), 0.5%; ninth nerve (glossopharyngeal), 1.4%; and tenth nerve (vagus), 0.7%. The importance of preservation of function of the nervus intermedius of Wrisberg is stressed. These results emphasize the advantages of the translabyrinthine approach, offering greater security to the facial nerve and lower morbidity.

A brief review of the lingual nerve anatomy is followed by an examination of the consequences of injury to the lingual nerve during mandibular wisdom tooth extraction on sensibility and sensorial activities. The circumstances of such injury are described as a function of the position of the tooth together with means of prevention. The clinical course of injury to the lingual nerve is unpredictable and varies over time and in quality of recovery. No prognosis can be made before a reasonable delay of 18 months to 2 years. Prevention remains the best treatment and consists of using a flexible bar to protect the nerve during the operation. Rate of legal disability compensation is estimated at 2 to 5%.

The 11th nerve syndrome classically involves the majority of patients undergoing neck dissections even when the accessory nerve is preserved. A preliminary analysis of our data of 31 of 44 patients who underwent neck dissections from a prospective study showed numerous findings of shoulder disability that are not attributable to accessory nerve palsy but are well described by the syndrome of adhesive capsulitis of the glenohumeral joint. At 1 month postoperatively, although accessory nerve palsy symptoms were common, adhesive capsulitis symptoms were significant. At 6 months, the frequency of accessory nerve palsy symptoms was less as the accessory nerve had begun to recover. At 12 and 18 months, when most of the accessory nerves had recovered, the accessory nerve palsy symptoms were comparatively uncommon while the adhesive capsulitis symptoms predominated as the remaining symptoms of the 11th nerve syndrome. We propose that adhesive capsulitis is a principal component of the 11th nerve syndrome that can significantly compound the morbidity of a neck dissection even when the accessory nerve recovers. We also propose that adhesive capsulitis accounts for the persistence and variability of shoulder symptoms after neck dissection that cannot be attributed to trapezius muscle dysfunction.

Jugular foramen tumors involve a critical area of the skull base. Usually they are characterized by palsy of the ninth, tenth, and eleventh cranial nerves. Depending on the extent of the tumor there are various approaches to the skull base and various surgical strategies to preserve the cranial nerves. The study is based on 31 patients who were operated on between 1982 and 1989 at the University ENT and Neurosurgery Departments in Freiburg and Mainz. The neurological findings were analyzed on admission, on discharge, and in the follow-up. While there was partial or complete dysfunction of the lower cranial nerves on discharge, long-term compensation was excellent. All patients were able to breath normally and maintain their weight by oral diet. Rerouting of the facial nerve endangers its postoperative function. Nevertheless, the long-term follow-up demonstrated excellent recovery and good functional and cosmetic results.

Endovascular obliteration of hypervascular lesions of the head and neck has become clinically accepted, but it may cause stroke and peripheral cranial nerve palsy. By using a flow-controlled technique to deliver the materials and by knowing the vascular anatomy of the cranial nerves, these problems are less likely to occur. Occasionally, though, vascular anatomy is distorted by the lesion or is anomalous in its distribution. A provocative test of lidocaine injected into the appropriate artery seems to offer a functional test of whether the capillary bed will tolerate small-particle or liquid plastic occlusion. Twenty-six patients had various branches of their external carotid arteries challenged with lidocaine. Three developed transient palsies, and their treatments were modified. None of the 26 patients developed a complication of embolization.

The high frequency of permanent functional disturbance of the inferior alveolar nerve after sagittal osteotomy of the mandibular ramus is a disadvantage to which attention is always drawn in the different operating statistics. The authors, on the basis of previous experimental research, and in order to reduce the incidence of this disadvantage, have carried out sagittal osteotomy of the ramus in a series of patients by performing the splitting of the two cortical plates using a thin cement spatula as a chisel. The results have been extremely encouraging as the authors have observed only one case of permanent functional deficit of the inferior alveolar nerve and they have even noticed a very low incidence of temporary impairment.