Intraoperative monitoring of the abducens nerve in extended endonasal endoscopic approach: A pilot study technical report

BackgroundTo determine the reliability and usefulness of intraoperative monitoring of the abducens nerve during extended endonasal endoscopic skull base tumor resection.MethodsWe performed abducens nerve intraoperative monitoring in 8 patients with giant clival lesions recording with needle electrodes sutured directly into the lateral rectus muscles of the eye to evaluate spontaneous electromyographic activity and triggered responses following stimulation of the abducens nerves.ResultsA total of 16 abducens nerves were successfully recorded during endoscopic endonasal skull base surgeries. Neurotonic discharges were seen in two patients (12% [2/16] abducens nerves). Compound muscle action potentials of the abducens nerves were evoked with 0.1–4 mA and maintained without changes during the neurosurgical procedures. No patient had new neurological deficits or ophthalmological complications post-surgery.ConclusionsIntraoperative monitoring of the abducens nerve during the extended endonasal endoscopic approach to skull base tumors appears to be a safe method with the potential to prevent neural injury through the evaluation of neurotonic discharges and triggered responses.     

Free rectus abdominis muscle flap reconstruction of the middle and posterior cranial base

A multidisciplinary approach by the neurosurgeon, ENT surgeon, and plastic surgeon has been used in seven patients with extensive tumors involving the middle and posterior skull base. Wide resection of these tumors was accomplished, and the resultant defect of the cranial base was reconstructed using free rectus abdominis muscle flaps. The free muscle flap has been used to reconstruct defects in the posterior and lateral walls of the nasopharynx, obliterate the exposed paranasal sinuses, and cover tenuous dural repairs or dural grafts overlying the temporal lobe and posterior fossa to prevent cerebrospinal fluid leakage and ascending meningitis.     

"Keystone" approach for intracranial nasofrontal dermoid sinuses

Nasofrontal dermoid sinus tracts that extend intracranially through the foramen cecum or ethmoid can be difficult to completely resect. Complete extirpation of nasofrontal dermoid sinus cysts is essential for effective treatment of this problem to minimize the chance of recurrence. The authors describe a new technique based on parasagittal osteotomies through the supraorbital bar, or bandeau, that ensures that the resection of the nasofrontal dermoid sinus cysts is complete. This technique also limits the size of the external nasal incision and enhances the surgeon's exposure of the anterior cranial base for resection of intradural extension. This approach also enhances exposure for the direct repair of the dura and the cranial vault.     

Treatment of craniomaxillofacial fibrous dysplasia: how early and how extensive?

Twenty-eight craniomaxillofacial fibrous dysplasia patients were treated as early as the symptoms occurred. The principles of surgical treatment were based on the zones of involvement: total excision of dysplastic bone of fronto-orbital, zygoma, and upper maxillary origin (zone 1) and bone reconstruction primarily; conservative excision on hair-bearing skull (zone 2), central cranial base (zone 3), and tooth-bearing bones (zone 4); and optic canal decompression on patients with orbital dysplasia and decreasing visual acuity. Patients were followed for 1 to 11 years (average 5.3 years). No recurrence or invasion of the fibrous dysplasia into the grafted bone was seen. One patient had orthognathic maxillary osteotomy on the reconstructed maxilla 6 years after initial reconstruction. Five of 19 patients with alveolar dysplasia had a recurrence and were reshaped. One patient had mandibular sagittal osteotomies to set back the prognathic, fibrous dysplasic mandible after three attempts at conservative shaving. Another patient with mandibular fibrous dysplasia had recurrence with pain and a hemimandibulectomy with successful immediate free vascularized iliac bone graft reconstruction.     

经鼻内镜手术进展

颅底手术正随着经鼻内镜手术的发展而发生着转变。经鼻内镜手术最初开发于鼻窦手术,但其适应症已逐渐扩大到其它领域,可以用于治疗大量的疾病。经鼻内镜手术的主要优点是：它利用天然的孔道来处理大量的颅内、鼻窦病变,避免了皮肤切口、面部骨瓣切口、脑回缩等直接开颅所不可避免的后遗症。与传统的神经外科手术相比,发病率和死亡率下降,并间接减少了住院时间和管理成本。本文就经鼻内镜手术的进展进行综述。在综述中阐述了经鼻内镜手术的适应症和基本原则,以及显露、特别是重建技术的进展,这些进展要求在可接受的并发症前提下达到更广泛的切除;讨论了经鼻内镜手术的局限性,尤其是,虽然这种手术往往是“微创”,但它并不是完全没有并发症;展望了经鼻内镜手术的适应症会不断拓宽,并发症会越来越少的美好未来。     

经鼻内镜手术进展

颅底手术正随着经鼻内镜手术的发展而发生着转变。经鼻内镜手术最初开发于鼻窦手术,但其适应症已逐渐扩大到其它领域,可以用于治疗大量的疾病。经鼻内镜手术的主要优点是:它利用天然的孔道来处理大量的颅内、鼻窦病变,避免了皮肤切口、面部骨瓣切口、脑回缩等直接开颅所不可避免的后遗症。与传统的神经外科手术相比,发病率和死亡率下降,并间接减少了住院时间和管理成本。本文就经鼻内镜手术的进展进行综述。在综述中阐述了经鼻内镜手术的适应症和基本原则,以及显露、特别是重建技术的进展,这些进展要求在可接受的并发症前提下达到更广泛的切除;讨论了经鼻内镜手术的局限性,尤其是,虽然这种手术往往是"微创",但它并不是完全没有并发症;展望了经鼻内镜手术的适应症会不断拓宽,并发症会越来越少的美好未来。     

颅底脊索瘤的影像学诊断及治疗研究（附26例报告）

目的：探讨颅底脊索瘤的CT、MRI表现及治疗措施。方法：回顾性分析经病理证实的26例脊索瘤患者的临床资料。肿瘤位于鞍区及鼻咽部者9例,位于中颅窝者5例,位于后颅窝者8例,混合型4例。手术入路：额颞入路一翼点开颅9例,鼻内镜下经蝶入路5例,颞下、颞枕及扩大中颅窝入路8例,4例未手术行放射治疗。结果：肿瘤全切8例,大部及次全切14例,围手术期未见死亡病例。25例患者获得随访;3例于术后1年内复发,其中2例死亡,余者颅神经损伤及肢体症状均有改善。结论：脊索瘤无典型临床表现,现多可通过术前影像学检查得以诊断,少数位于特殊位置者需与垂体瘤,颅咽管瘤,三叉神经鞘瘤等鉴别;肿瘤全切较为困难,根据需要选择相应的手术入路可明显提高手术效果;放疗可作为术后辅助治疗。     

颅底脊索瘤的影像学诊断及治疗研究(附26例报告)(英文)

目的:探讨颅底脊索瘤的CT、MRI表现及治疗措施。方法:回顾性分析经病理证实的26例脊索瘤患者的临床资料。肿瘤位于鞍区及鼻咽部者9例,位于中颅窝者5例,位于后颅窝者8例,混合型4例。手术入路:额颞入路-翼点开颅9例,鼻内镜下经蝶入路5例,颞下、颞枕及扩大中颅窝入路8例,4例未手术行放射治疗。结果:肿瘤全切8例,大部及次全切14例,围手术期未见死亡病例。25例患者获得随访;3例于术后1年内复发,其中2例死亡,余者颅神经损伤及肢体症状均有改善。结论:脊索瘤无典型临床表现,现多可通过术前影像学检查得以诊断,少数位于特殊位置者需与垂体瘤,颅咽管瘤,三叉神经鞘瘤等鉴别;肿瘤全切较为困难,根据需要选择相应的手术入路可明显提高手术效果;放疗可作为术后辅助治疗。     

Extensive and complex defects of the scalp, middle third of the face, and palate: the role of microsurgical reconstruction

Twenty-one patients with gigantic defects of the scalp and middle third of the face and palate following excision of neglected or recurrent tumors, burns, and infections have undergone microsurgical reconstruction. Wide resection of the middle third of the face, orbit, and palate requires "complex" three-dimensional volume reconstruction, whereas extensive defects of the scalp and skull (exceeding 80 cm2) require coverage of the larger surface area soft-tissue defect and the exposed brain and dura. The latissimus dorsi free-muscle flap and split-thickness skin graft have become our methods of choice for extensive scalp and skull defects. The latissimus dorsi musculocutaneous free flap is preferable for reconstruction of complex palatal and external skin and orbital defects of the middle third of the face. Microsurgical free-tissue transfer reliably frees the oncologic surgeon from the constraints imposed by conventional reconstructive techniques and may therefore allow improved curative or at least palliative resection of these extensive tumors.     

高流量颅外内血管搭桥技术在颅底肿瘤手术中的应用进展

颅底肿瘤尤其是侵及颈内动脉等颅内主供血血管的肿瘤治疗一直是神经外科的难题,由于此类肿瘤与重要血管的关系密切,手术风险极大,导致治愈率底下。而颅外内血管搭桥技术通过重建颅内血运,可以有效提升此类肿瘤的全切率。本文回顾了高流量颅外内血管搭桥技术的历史进展、探讨了颅外内血管搭桥技术辅助切除颅底肿瘤的意义所在,复习文献归纳了该技术应用的适应症、术中注意事项及其疗效与争议,旨在为其临床推广应用提供更多的参考依据。熟练及合理地应用颅外内血管搭桥技术,制定个体化的治疗方案,复杂颅底肿瘤的治愈率将会得到进一步提升。     

Development and evolution of the tetrapod skull–neck boundary

The origin and evolution of the vertebrate skull have been topics of intense study for more than two centuries. Whereas early theories of skull origin, such as the influential vertebral theory, have been largely refuted with respect to the anterior (pre‐otic) region of the skull, the posterior (post‐otic) region is known to be derived from the anteriormost paraxial segments, i.e. the somites. Here we review the morphology and development of the occiput in both living and extinct tetrapods, taking into account revised knowledge of skull development by augmenting historical accounts with recent data. When occipital composition is evaluated relative to its position along the neural axis, and specifically to the hypoglossal nerve complex, much of the apparent interspecific variation in the location of the skull–neck boundary stabilizes in a phylogenetically informative way. Based on this criterion, three distinct conditions are identified in (i) frogs, (ii) salamanders and caecilians, and (iii) amniotes. The position of the posteriormost occipital segment relative to the hypoglossal nerve is key to understanding the evolution of the posterior limit of the skull. By using cranial foramina as osteological proxies of the hypoglossal nerve, a survey of fossil taxa reveals the amniote condition to be present at the base of Tetrapoda. This result challenges traditional theories of cranial evolution, which posit translocation of the occiput to a more posterior location in amniotes relative to lissamphibians (frogs, salamanders, caecilians), and instead supports the largely overlooked hypothesis that the reduced occiput in lissamphibians is secondarily derived. Recent advances in our understanding of the genetic basis of axial patterning and its regulation in amniotes support the hypothesis that the lissamphibian occipital form may have arisen as the product of a homeotic shift in segment fate from an amniote‐like condition.     

Craniofacial deformity in patients with uncorrected congenital muscular torticollis: an assessment from three-dimensional computed tomography imaging

Congenital muscular torticollis is caused by idiopathic fibrosis of the sternocleidomastoid muscle that restricts movement and pulls the head toward the involved side. Deformation of the craniofacial skeleton will develop if the restriction is not released and result in aesthetic and functional problems. The purpose of this study was to use three-dimensional computed tomography imaging for qualitative and quantitative evaluation of the craniofacial deformity in a series of patients with uncorrected congenital muscular torticollis, and to assess age as a precipitating factor for severity of the deformity. A total of 14 patients from 1 month to 24 years of age were included. The skull images were rotated into standard orientation and reconfigured for evaluation of the cranium, endocranial base, and facial skeletal structures. The midlines of cranial base and facial bone, angle of midline deviation, width of each hemicranium and hemiface, and the orbital index were defined and measured. The results showed that the cranium and cranial base deformation took place as early as in infant stage, with the most prominent change occurring in the posterior cranial fossa. Facial bone asymmetry started to appear after 5 years of age, at which time the mandibular and occlusal abnormalities were observed. The deformity of the orbits and maxilla occurred at an older age, characterized by the deviation and decreased vertical height on the affected side. The severity of the observed deformities increased with age. The angle of midline deviation was 2.48 +/- 1.68 degrees in the cranial base and 3.26 +/- 3.28 degrees on the facial bone. Both of the midline deviations were significantly correlated with age. Compared with the contralateral side, the width of the ipsilateral posterior hemicranium was longer (54.36 +/- 6.72 mm versus 50.81 +/- 6.55 mm), and the width of the ipsilateral lower hemiface was shorter (35.30 +/- 7.27 mm versus 43.49 +/- 11.34 mm). Both differences were statistically significant. Measurement of the orbital index demonstrated a significantly flatter orbit on the ipsilateral side (89.48 +/- 0.11 versus 92.74 +/- 0.08). This study showed that the cranium and cranial base deformity occurred early in patients with uncorrected torticollis, while the facial bone deformity occurred in childhood stage. The cranial and facial deformity became more severe with age. Early release of the muscle restriction is advised to prevent craniofacial deformation.     

游离皮瓣在晚期颅底肿瘤术后组织缺损中应用效果分析

目的:探讨使用游离皮瓣修复晚期颅底肿瘤术后缺损组织的效果及适应症。方法:选择2009年1月至2013年9月在我院行晚期颅底肿瘤术并且需要进行组织修复的病患74例作为研究对象。根据病患选择的修复方式分为观察组和对照组各37例。观察组采用游离皮瓣,而对照组使用钛网修复。观察两组相应指标,比较不同修复材料的修复效果。结果:观察组手术效果显效率和总有效率为40.54%(15/37)、97.30%(36/37),显著高于对照组,差异有统计学意义(P0.05)。观察组在术中出血量、手术时间以及术后愈合时间等方面均优于对照组,差异有统计学意义(P0.05)。观察组术后出现颅内感染、脑脊液漏和皮瓣坏死比率为8.11%(3/37)、0(0/37)和2.70%(1/37)都少于对照组,差异有统计学意义(P0.05)。结论:采用前臂皮瓣进行晚期颅底肿瘤术后缺损组织修复效果更好,皮瓣存活率更高。比传统钛网修复引起的并发症更少,值得临床推荐使用。     

Retro-orbicularis oculus fat (ROOF) resection in aesthetic blepharoplasty: a 6-year study in 63 patients

Sixty-three nonconsecutive patients have undergone resection of the retro-orbicularis oculus fat (ROOF) in conjunction with aesthetic blepharoplasty. In these patients, a consistent and useful ability to soften and flatten heaviness and bulkiness in the lateral upper orbital region was seen. Two patients developed postoperative hematoma, and two different patients had transient dry-eye symptoms following blepharoplasty. Twenty percent of patients had a transient degree of numbness in the lateral supraorbital nerve region, and all patients noted some transient numbness over the lateral upper brow region. No patient demonstrated significant paralysis of the orbicularis oculus or corrugator muscle. From this experience, retro-orbicularis oculus fat resection would appear to be a useful adjunct to standard blepharoplasty techniques in selected patients.     

Use of the free vastus lateralis flap in skull base reconstruction

Free flaps in skull base reconstruction are indicated for providing an effective separation of the intracranial cavity from the oronasal space, for eliminating a dead space, and for the treatment of established wound complications such as dural exposures and cerebrospinal fluid leaks. Seven patients with cranial base defects underwent reconstructions using a free vastus lateralis muscle flap. In two cases, a vastus lateralis flap was raised to incorporate the anterolateral thigh skin as a myocutaneous flap. In four cases, a free flap was indicated for reconstruction following tumor ablation, and in three cases, for the resolution of wound or cerebrospinal fluid leak complications following previous cranial base surgery. All flaps were successful, with no partial failures. In those patients undergoing tumor ablative surgery, the cranial cavity was effectively sealed from the oronasal cavity. Patients with established wound complications following previous cranial base surgery had a complete resolution of their symptoms. This report discusses the suitability of the vastus lateralis flap for skull base reconstruction in terms of the availability of adequate muscle volume to fill dead space, vascularized fascia to augment dural repairs, and the freedom to use skin if required for internal lining or external skin cover. This flap also provides an extremely long pedicle, allows simultaneous flap harvest, and has low donor site morbidity.     

Ontogenic growth changes of the skull base in four genera of nonhuman primates.

Cross-sectional studies of the degree of the cranial base flexion were carried out in infant, juvenile and adult skulls in four genera of nonhuman primates (P. paniscus, H. lar, P. urinus, and M. mullatta). The cephalometric observations of the cranial base included linear and angular measurements of each specimen. The data obtained in this study showed that the anterior portion of the cranial base exhibits a significant shortening trend as the mammalian evolutionary scale ascends. Moreover, the growth pattern of the anterior portion of the skull base follows that of the facial bony structures. The ontogenic growth changes of the posterior portion of the skull base follows the growth pattern of the endocranial cavity. The significant trend of elongation in this area directly contributes to the posterior migration of the foramen magnum. The magnitude of these growth changes decreases as the evolutionary scale ascends. The angular measurements of the cranial flexion showed a less obtuse cranial base angle in young specimens and the ones higher on the mammalian scale. The skull kyphosis was less pronounced in these specimens and the anatomical features of the cranial base were more humanlike, including the balance of the head expressed by the position of the foramen magnum.     

The use of miniplates in craniomaxillofacial surgery

Miniplates were used in craniomaxillofacial surgery for fixation in the skull, maxilla, and/or mandible in 74 patients with minimal or no intermaxillary wiring. Procedures included forehead and orbital repositioning, frontofacial advancement, Le Fort III and particularly Le Fort I osteotomies, as well as mandibular osteotomies and fracture repair. The miniplates provided stable fixation and, compared with other techniques, improved airway safety. The complication rate was low: there were no infections, but two plates (1 percent) became exposed in the buccal sulcus. Although application of miniplates lengthened surgery and increased the cost of the procedure, the savings in intensive care monitoring more than offset these costs. The stability of fixation minimizes the opportunity to reposition the fragments postoperatively with training elastics. Therefore, meticulous technique is mandatory, with particular emphasis on passive fitting of the plates and precise drilling of screw holes.     

Intentional cranial vault deformation and induced changes of the cranial base and face

Three morphologically distinct populations of Peruvian crania (n = 130) were metrically analysed to quantify changes resulting from intentional artificial vault deformation. Two of these samples are artificially deformed (anteroposterior [AP] and circumferential [C] types). Measurements taken from lateral radiographs demonstrated that alternative forms of the cranial base angle (N-S-Ba, planum angle, planum sphenoidale to plane of the clivus and PANG angle, planum sphenoidale to basion-sella plane) and the orbital and OANG angles (orbital roof to plane of the clivus and basion-sella plane, respectively) of both deformed groups increased while the angle S-Ba-O decreased significantly with respect to the undeformed (N) sample. Changes in the AP group are largely due to anteroinferior displacement of the basion-sella plane. Similar changes in group C are amplified by this group's posterosuperior frontal migration. This migration results in a relatively shallow orbit at the orbital plate/frontal squama interface. Unlike the deformation experienced by the external vault plates, the basion-sella plane orientation remains stable with respect to the Frankfort Horizontal. Additionally, nasal region measurements such as maximum nasal aperture breadth and nasal height were largely stable between each deformed group and the undeformed group. However, facial (bimaxillary and bizygomatic), basicranial, cranial, and frontal breadths decreased significantly from group AP to group N to group C. Thus, gross morphological facial changes between each undeformed group and the control group are largely accounted for by dimensional changes in peripheral structures. These results stress the importance of the dynamic interrelationship between the cranial vault and base in the development of the craniofacial complex.     

Reduction malarplasty through an intraoral incision: a new method

Until recently, osteotomies and surgeries to reposition prominent zygoma have been performed by means of a coronal incision or intraoral and preauricular incisions. Such incisions have penalties such as scars, the possibility of facial nerve injury, and long operative times. After reflecting on their past experiences with facial bone surgery, the authors developed an alternative approach. In this method, the cheekbone protrusion is corrected by performing an osteotomy and repositioning through an intraoral incision only. During the past 3 years, the authors have operated on 23 patients with malar prominences. The amount of bone to be removed is determined by preoperative interviews, physical examinations, and x-rays. Intraoral incisions provide access to the zygomatic body and lateral orbital rim. After L-shaped osteotomies (two parallel vertical and one transverse osteotomy at the medial part of the zygomatic body), the midsegment is removed. The posterior portion of the zygomatic arch was approached through the medial aspect and was outfractured using a curved osteotome. After completing the triple osteotomy, the movable zygomatic complex was reduced medially and fixed with miniplates and screws on the zygomaticomaxillary buttress. The patients were followed for 9.5 months, with acceptable results and few complications. The authors conclude that this technique is an effective and safe method of reduction malarplasty.