Floor Of Anterior Cranial Fossa Research Articles

The biportal transorbital approach: quantitative comparison of the anterior subfrontal craniotomy, bilateral transorbital endoscopic, and microscopic approaches.

The aim of this study was to assess the surgical use and applicability of a biportal bitransorbital approach. Single-portal transorbital and combined transorbital transnasal approaches have been used in clinical practice, but no study has assessed the surgical use and applicability of a biportal bitransorbital approach. Ten cadaver specimens underwent midline anterior subfrontal (ASub), bilateral transorbital microsurgery (bTMS), and bilateral transorbital neuroendoscopic surgery (bTONES) approaches. Morphometric analyses included the length of the bilateral cranial nerves I and II, the optic tract, and A1; the area of exposure of the anterior cranial fossa floor; craniocaudal and mediolateral angles of attack (AOAs); and volume of surgical freedom (VSF; maximal available working volume for a specific surgical corridor and surgical target structure normalized to a height of 10 mm) of the bilateral paraclinoid internal carotid arteries (ICAs), bilateral terminal ICAs, and anterior communicating artery (ACoA). Analyses were conducted to determine whether the biportal approach was associated with greater instrument freedom. The bTMS and bTONES approaches provided limited access to the bilateral A1 segments and the ACoA, which were inaccessible in 30% (bTMS) and 60% (bTONES) of exposures. The average total frontal lobe area of exposure (AOE) was 1648.4 mm2 (range 1516.6-1958.8 mm2) for ASub, 1658.9 mm2 (1274.6-1988.2 mm2) for bTMS, and 1914.9 mm2 (1834.2-2014.2 mm2) for bTONES exposures, with no statistically significant superiority between any of the 3 approaches (p = 0.28). The bTMS and bTONES approaches were significantly associated with decreases of 8.7 mm3 normalized volume (p = 0.005) and 14.3 mm3 normalized volume (p < 0.001) for VSF of the right paraclinoid ICA compared with the ASub approach. No statistically significant difference in surgical freedom was noted between all 3 approaches when targeting the bilateral terminal ICA. The bTONES approach was significantly associated with a decrease of 105% in the (log) VSF of the ACoA compared with the ASub (p = 0.009). Although the biportal approach is intended to improve maneuverability within these minimally invasive approaches, these results illustrate the pertinent issue of surgical corridor crowding and the importance of surgical trajectory planning. A biportal transorbital approach provides improved visualization but does not improve surgical freedom. Furthermore, although it affords impressive anterior cranial fossa AOE, it is unsuitable for addressing midline lesions because the preserved orbital rim restricts lateral movement. Further comparative studies will elucidate whether a combined transorbital transnasal route is preferable to minimize skull base destruction and maximize instrument access.

Hemophilic Pseudotumor of Paranasal Sinuses in a Child with Severe Hemophilia a Receiving Emicizumab: A Case Report

Emicizumab, a bispecific humanized monoclonal antibody, bridges activated factor IX (FIX) and FX to restore the function of missing activated FVIII in individuals with hemophilia A (PwHA). Prophylaxis with subcutaneous emicizumab promotes adequate hemostasis in PwHA. Emicizumab prophylaxis in children with hemophilia A has been approved in the United States for use in PwHA ages newborn and older, with or without FVIII inhibitors. We report a 2-year-old boy with severe congenital hemophilia A who initially received prophylaxis with standard half-life factor VIII but later switched to subcutaneous emicizumab at 6 mg/kg every four weeks due to difficult IV access and parental preference. Shortly after starting emicizumab, the patient presented to the hospital with severe episodic epistaxis from the left nostril, requiring ICU admission and ENT consultation. Despite treatment, the condition did not improve, prompting the need for imaging studies. Subsequently, the patient developed ipsilateral eye proptosis and a mass protruding from the left nostril. CT and MRI imaging of the orbit revealed an expansible soft tissue mass measuring 2 x 2.5 x 4 cm occupying the right sphenoid sinus, extending to the nasal cavity. The mass had caused erosion of the clivus and the anterior cranial fossa floor, extending to the middle cranial fossa (Figures 1 &amp; 2). He underwent endoscopic nasal debulking of the left nostril mass, and the pathological examination revealed a cystic mass with a thick capsule and intra-cystic blood clots, consistent with the characteristics of a hemophilic pseudotumor (HP). The fibrous stroma contained hemosiderin-laden macrophages with no evidence of malignancy. Emicizumab was discontinued before the operation, and the patient received several doses of recombinant FVIII to maintain hemostasis. Despite the debulking procedure, the patient continued to experience episodic epistaxis and joint bleeding. An inhibitor assay was performed at that time and showed high levels, leading to a switch to on-demand FVIII treatment for hemophilia A with an inhibitor. Managing the bleeding episodes with bypassing agents proved challenging, and the family expressed dissatisfaction. A decision was made to resume emicizumab treatment, and the patient eventually stabilized, experiencing no bleeding for nearly six months. Additionally, he regularly follows up with ENT specialty, with no further intervention or progression of the tumor. Notably, he did not receive any bypassing agents concomitantly with emicizumab. HP is characterized by encapsulated blood clots accumulating in extravascular tissues, especially the musculoskeletal system, in patients with bleeding tendencies, particularly hemophiliacs. It is a benign, expansible, soft tissue-like mass that exerts pressure on surrounding structures, mimicking a locally invasive malignancy. HP is a hematoma that grows and causes bone erosion through repeated bleeding episodes. A literature review revealed that HP is a rare hemorrhagic complication that develops in 1-2% of patients with severe hemophilia (Magallón et al. Am J Hematol. 1994). Its occurrence in patients receiving emicizumab prophylaxis is extremely rare. The first reported case involved a Japanese child with hemophilia who presented with a pseudotumor occupying the left maxillary sinus after repeated episodes of epistaxis. The mass caused a downward deviation of the ipsilateral eye and bulged into the buccal cavity. The patient received monthly prophylaxis with emicizumab at 6 mg/kg (Kawahara et al. Int J Hematol. 2022), but unlike our patient, he received bypassing agents concomitantly. Our reported case is unique because HP developed independently of bypassing agent therapies, as the patient did not receive any bypassing agents before the tumor's development. The likely explanation is related to repeated bleeding insults to the same anatomical location, leading to the cumulative development of hematoma and HPs. Another possibility could be attributed to the known adverse thrombotic effects of emicizumab treatment. Physicians treating hemophilia should remain vigilant for abnormal clinical signs, such as new masses in patients receiving emicizumab, which could indicate HP.

Transorbital Microsurgery: An Anatomical Description of a Minimally Invasive Corridor to the Anterior Cranial Fossa and Paramedian Structures.

Objectives Transorbital neuroendoscopic surgery (TONES) has ignited interest in the transorbital access corridor, increasing its use for single and multi-portal skull base interventions. However, the crowding of a small corridor and two-dimensional viewing restrict this access portal. Design Cadaveric qualitative study to assess the feasibility of transorbital microsurgery (TMS). Setting Anatomical dissection steps and instrumentation were recorded for homogeneous methodology. Participants Six cadaveric specimens were systematically dissected using TMS to the anterior cranial fossa and paramedian structures. Main Outcome Measures Anatomical parameters of the TMS craniectomy were established, and the visible and accessible neuroanatomy was highlighted. Results A superior lid crease incision achieved essential orbital rim exposure and preseptal dissection. The orbital roof craniectomy is defined by three boundaries: (1) frontozygomatic suture to the frontosphenoid suture, (2) frontal sinus and cribriform plate, and (3) frontal sinus and orbital rim. The mean (standard deviation) craniectomy was 440 mm 2 (78 mm 2 ). Exposing the ipsilateral optic nerve and internal carotid artery obviated the need for frontal lobe retraction to identify the A1-M1 bifurcation as well as near-complete visualization of the M1 artery. Conclusion TMS is a feasible corridor for intracranial access. Mobilization of orbital contents is imperative for maximal intracranial access and protection of the globe. TMS enables access to the frontal lobe base, ipsilateral optic nerve, and most of the ipsilateral anterior circulation. This cosmetically satisfactory approach causes minimal destruction of the anterior skull base with satisfactory exposure of the anterior cranial fossa floor without sinus invasion.

PMON120 Clinical Course Of Untreated Giant Invasive Macroprolactinomas- A Case Series

Abstract Introduction Giant invasive prolactinomas are rare pituitary tumours and have a male preponderance of 9: 1. In majority of cases, dopamine agonists (DA) are the treatment of choice in lowering prolactin and tumour shrinkage. Surgery may be opted in those with acute compressive symptoms or visual loss. Prolactinomas are known to invade the sellar floor, sphenoid sinus and clivus. Spontaneous CSF leak is rare in untreated patients with invasive prolactinomas compared to those on DA who respond with rapid tumour shrinkage that causes unplugging of the conduits resulting in CSF rhinorrhoea. We present 5 male patients with untreated giant invasive prolactinomas with skull base destruction where close surveillance was opted over DA treatment. Results Five male patients with median age of 73±10 years were studied. 1 patient presented with headache, vomiting and 6th nerve palsy which spontaneously resolved over weeks. 2 patients were diagnosed during work up of other hormonal deficiencies and in 2 patients giant tumours were incidentally found on imaging for head injury. Prolactin values ranged from 55,641 to 835,800 mIU/L. Hormonal deficiency was present in 3/5; anterior hypopituitarism (1) and symptomatic secondary hypogonadism (2). MRI imaging in all patients showed extensive skull base bony erosion, with tumour invasion into sphenoid sinus and clivus. Additionally, the patient with largest tumour had invasion into right orbital roof and floor of right anterior cranial fossa. In other patients, tumour had also invaded occipital condyles (1), bilateral cavernous sinus (1). All patients were discussed in tertiary neurosurgical MDT. As the risk of CSF leakage due to tumour shrinkage outweighed the benefits of tumour reduction, a decision not for medical treatment was agreed with patients and planned for active surveillance with MRI scans and regular clinical and visual fields assessments. The mean follow-up period was 4±1 years. One patient was very frail and decided not for radiological surveillance. DA treatment is being considered for the patient with the largest tumour which has grown further causing frontal lobe invasion. There was no significant tumour size increase in other 4 patients and none had spontaneous CSF leak. Discussion Risk stratification for CSF leak with DA treatment is difficult as it depends on the invasion, tumour response to DAs and the extent of underlying bony destruction. This may cause a dilemma on whether or not to treat some patients with DAs. The risk of CSF leak, bacterial meningitis and the subsequent need for urgent surgical repair may outweigh the benefits of tumour reduction with DAs particularly in some patients with low symptom burden. In our experience, patient counselling, active radiological surveillance and considering treatment with change in symptoms (visual deterioration, compressive pathology) could be an appropriate management option in such patients. Presentation: Monday, June 13, 2022 12:30 p.m. - 2:30 p.m.

Fluid-Filled Dehiscences in the Anterior Cranial Fossa Floor: A Magnetic Resonance Imaging Study

To date, only limited information regarding the anterior cranial fossa floor (AFF) and the appearance of sites of dehiscence and potential channels has been available. We aimed to evaluate this region with thin section magnetic resonance imaging (MRI). A total of 65 patients underwent thin-sliced coronal T2-weighted MRI. The AFF was divided into 3 parts for analysis: the anterior, middle, and posterior. Dehiscences were identified in 84.6% of 65 patients with apparently transmitting channels. In 49.2% of the patients, the dehiscences were located in the anterior part, whereas they were located in the middle and posterior parts in 52.3% and 12.3%, respectively. The morphology and number of these dehiscences were highly variable. In 12.3%, channels in the dehiscences were distributed extradural. Statistically, dehiscences were more frequently identified on the left side in any part of the AFF. With thin-sliced, coronal T2-weighted MRI, dehiscences were frequently identified in the anterior two-thirds of the AFF. Further study is warranted to determine the role of AFF channels and dehiscences, including possibly for cerebrospinal fluid drainage.

Plastic closure of bone defects of anterior cranial fossa floor in surgery of benign and malignant craniofacial tumors

Objective: to analyze the results of using various methods of plastic closure of bone defects of the anterior cranial fossa (ACF) floor when removing craniofacial tumors of the ACF floor depending on the size of the defect. Materials and methods. A retrospective analysis of treatment outcomes of 122 patients with craniofacial tumors of the ACF floor was carried out. According to the nature of the lesions malignant craniofacial tumors were detected in 98 (80.3%) patients, and benign ones in 24 (19.7%) patients. The following neurosurgical approaches to craniofacial tumors of the ACF floor were used: bifrontal - in 58 (47.5%) patients, subcranial - in 49 (40.2%), transbasal Derome - in 8 (6.5%), frontotemporal - in 4 (3.25%), expanded endoscopic - in 3 (2.45%). In 52 (42.6%) cases, endoscopic endonasal assistance was used, most often in the case of plasty of large ACF floor defects to revise the surgical defect, assess the sufficiency of plasty and tamponade of the nasal cavity with balloon catheters. Results. Patients were divided into groups depending on the bone defect of the ACF floor: median - in 27 (22.1%), middle-expanded - in 71 (58.2%), middle-lateral - in 24 (19.7%). The following types of plasty of the bone defect of the ACF floor were used: pedicle flap - 83 (68.0%) cases, free flap - 22 (18.1%), pedicled periosteal flap with reinforcement - 17 (13.9%). Postoperative complications occurred in 17 (13.9%) patients: nasal liquorrhea in 10 (8.2%) patients (of which 6 underwent reoperation to eliminate it), in 7 patients it was complicated by meningoencephalitis, in other 7 (5.7 %) - meningoencephalitis without signs of nasal cerebrospinal fluid. Postoperative mortality was 0.71% (1 patient). The frequency of nasal cerebrospinal fluid in the group of plasty using a free flap was 13.6% (3 cases), meningoencephalitis - 4.5% (1 observation), in the group of plasty using pedicle flap - 4.8% (4 cases) and 6.0% (5 observations), in the group of plasty using a pedicle flap with reinforcement - 17.6% (3 cases) and 11.7% (2 observations). In 33 (27.1%) cases the use of the author's method of bone defect plasty of the ACF floor with duplication of complications were not registered. Conclusions. Significant size and spread of bone defects of the ACF floor increase the risk of postoperative complications. The use of free flaps for plasty of the bone defect of the ACF floor is ineffective and is associated with a high risk of complications. The proposed method of plasty of the posterior parts of the ACF floor by duplication of the periosteal flap promotes the sealing of the posterior parts, where suturing causes certain difficulties. Reinforcement of plasty from the side of the nasal cavity due to endoscopic technique using tamponade or balloon catheters reduces the incidence of postoperative complications.

Rhinocerebral aspergillosis

A 27-year-old man presented to our hospital with a 4-month history of bilateral frontal headache, irritability, frontal lobe signs, bilateral proptosis, and nasal obstruction. He had no other signs or symptoms of a systemic illness. Rhinoscopy showed a soft tissue mass obstructing both nasal airways. A CT scan of his head showed hyperdense lesions involving both the paranasal sinuses (figure), with expansions into the frontal interdiploë spaces, and some calcification (figure). An MRI scan of the brain showed a soft tissue mass extending along the anterior cranial fossa floor up to the sellar and parasellar regions (figure). Endoscopic biopsy was inconclusive; however, because of raised intracranial pressure, the patient was taken to surgery for craniotomy and excision of the lesion.

Atypical Olfactory Neuroblastoma Presenting as Sinonasal Polyposis with Nasopharyngeal Extension: A Case Report

Background: Olfactory neuroblastoma also known as Esthesioneuroblastoma (ENB) is a tumor arising from the basal layer of olfactory epithelium in the superior recess of the nasal cavity in the region of cribriform plate. Incidence peaks once in 11 - 20 years of age and again in 50 - 60 years of age. It is equally found in men and women. Aim: The main aim of this case report is to characterize the clinical features of ENB showing nasopharyngeal involvement and its importance in the differential diagnosis of sinonasal neuroendocrine malignancies. Case presentation: Two cases are reported. The first case was a 21-year-old male with symptoms of nasal obstruction, recurrent epistaxis, nasal discharge, headache and paresthesia over the face with an evolution of 1 year with no previous history of trauma. Diagnostic nasal endoscopy revealed reddish gray mass filling bilateral nasal cavities. Posterior rhinoscopy revealed mass coming through choanae and filling the nasopharynx. Endoscopic resection of tumor was done and postoperatively all the symptoms of the patient resolved. The second case was a 62-year-old male with complaints of nasal obstruction, nasal discharge, recurrent epistaxis, anosmia and difficulty in swallowing. On computed tomography, anteriorly, the mass was extending up to external nares and posteriorly up to the nasopharynx, superiorly up to nasal roof and inferiorly up to hard palate. No obvious erosion of floor of anterior cranial fossa was seen. No intracranial extension was seen. Surgery was advised but patient refused to undergo any treatment. Conclusion: This study highlights the characteristics and clinical features of ENB showing nasopharyngeal involvement and their importance in the differential diagnosis of sinonasal neuroendocrine malignancies.

Personal experience in transnasal endoscopic resection of the olfactory groove meningiomas. What can an otolaryngologist offer to a neurosurgeon?

Olfactory groove meningioma is a demanding therapeutic problem involving two medical specialties, otolaryngology and neurosurgery. The use of transnasal endoscopic (TNE) approach to the tumour has been proved effective in many publications. Three patients with meningiomas localized in olfactory groove were treated in 2011 and 2012 by the otolaryngologist-neurosurgeon team using TNE approach and neuronavigation. The diagnosis was based on MR and CT images. In all patients after tumour removal an endoscopic anterior cranial fossa floor reconstruction was performed using homogeneous cartilage or titanium mesh and Hadad-Bassagasteguy flap. During postoperative period in all patients lumbar drainage was used. There were no cerebrospinal fluid leakage episodes. No recurrence was observed in 22, 12 and 8 months of follow-up, respectively. The authors describe otolaryngological and neurosurgical aspects of TNE approach to anterior cranial fossa with special regard to possible radical resection (according to Simpson) and reconstruction of the bony postoperative defect. TNE is a feasible operative method in olfactory groove meningioma management due to good tumour visibility, lack of brain traction, limited neurovascular structure manipulation and acceptable risk of neurological deficiencies when compared to open approach. Cosmetic aspect and short hospitalization is also of great importance.

Endoscopic Endonasal Resection of Anterior Skull Base Meningiomas and Mucosa: Implications for Resection, Reconstruction, and Recurrence

Meningiomas of the anterior skull base are attractive tumors for resection via an endoscopic endonasal route. The use of the vascularized Hadad-Bassagasteguy nasoseptal flap has dramatically reduced the cerebrospinal fluid (CSF) leak rate-the veritable Achilles heel of this surgical approach. Benign meningiomas, however, can erode through the nasal mucosa-the very same mucosa that is used to reconstruct the anterior cranial fossa floor. The goal of this study was to describe the presence of meningioma invasion into the mucosa in patients who underwent endoscopic endonasal resection of ventral skull base meningiomas. The implications of this finding are discussed with respect to resection, reconstruction, and recurrence. This is a retrospective review of three patients who underwent endoscopic endonasal complete resection of ventral skull base meningiomas. Surgically excised tissues were processed for routine histopathological analysis. A complete resection of the bone, dura, and tumor was performed in all three cases. Both patients with visual deficits improved. The first patient to undergo endoscopic surgical resection developed a CSF leak, but the later two patients with larger tumors did not. Histopathological analysis demonstrated mucosal invasion by World Health Organization (WHO) grade I meningioma in two of the three cases. Ventral anterior skull base meningiomas can invade through bone into the mucosa. Because the endoscopic endonasal resection of these meningiomas often requires the use of a vascularized nasoseptal flap to minimize CSF leak complications, it is possible that the nasoseptal flap itself may be compromised by tumor tissue. The creation of the nasoseptal flap should take the findings of this study into consideration to minimize late recurrence.

Refined and Simplified Surgical Landmarks for the MacCarty Keyhole and Orbitozygomatic Craniotomy

Precise placement of the MacCarty keyhole, a burr hole simultaneously exposing the anterior cranial fossa floor and orbit, provides accurate, efficient entry for orbitozygomatic and supraorbital craniotomies. To locate the optimal keyhole site, previous studies have used superficial landmarks that, in our experience, are not always visible or consistent on older crania. Therefore, we present a technique for accurate keyhole placement using landmarks that are easily visible across age ranges. From inside the cranium, 1-mm burr holes were placed along the anterior junction of the floor and lateral wall of the anterior cranial fossa in 50 adult skulls (100 sides, with calvaria removed). Additionally, from inside the orbit, 1-mm burr holes were placed into the lateral orbital roof. Exit sites of intracranial and intraorbital burr holes were referenced to the frontozygomatic suture. The center of the site between the exiting intracranial and intraorbital holes was deemed the best location for the keyhole. The keyhole center was 6.8 mm (mean) superior and 4.5 mm (mean) posterior to the frontozygomatic suture, which was easily identified on all specimens. Although this keyhole center was slightly more superior on right sides than left, this was not statistically significant. In a minority of specimens, the keyhole was located near the meningo-orbital foramen (22%) and the lateral extent of the frontal sinus (2%). We defined an alternative method for locating the MacCarty keyhole, based on a reliable external landmark, approximately 7 mm superior and 5 mm posterior to the frontozygomatic suture.

Nasal encephalocele in a child with mosaic trisomy 14

A 6-week-old boy presented with failure to thrive, pulmonary stenosis and stridor, which had worsened since birth. He also had undescended testes. On examination, he was noted to have facial asymmetry and his left eyelid did not close fully. He was noted to have a broad nose with a pit in the skin of his nose at the junction of the nasal bones and upper lateral cartilages in the midline from which hairs grew. His left ear was low set. He required laser laryngoplasty for severe laryngomalacia. Following investigations including computed tomography and MRI of the nose, brain and skull base, this pit was shown to continue up to the anterior skull base as a sinus tract. There was a defect in the skull floor anterior to the crista galli, and the crista galli itself was bifid. These clinical and radiological changes are consistent with the fibrous tract running from the nasal skin to the anterior cranial fossa floor being the embryological remnants of a nasal meningoencephalocele. Beneath the broad nasal bones was a widened nasal septum in the area enclosing the fibrous tract of the atrophied meningoencephalocele. The fibrous tract and nasal pit were removed from below and may require more extensive clearance if cysts or gliomas appear along the tract in the future. On review at 14 months, he had global developmental delay. He subsequently had feeding difficulties with delayed chewing skills and some aspiration. He had developed pigmentary mosaicism along the lines of Blaschko. Trisomy 14 mosaicism was diagnosed on skin biopsy

Distal anterior cerebral artery aneurysms: bifrontal basal anterior interhemispheric approach

Background Distal anterior cerebral artery (DACA) aneurysms are uncommon. Most authors have reported technical difficulties during surgery for these aneurysms, and a variety of surgical approaches have been advocated. Methods Over a period of 5 years (1999-2003), 67 patients with DACA aneurysms were operated. Twenty-eight of these were operated on through the bifrontal basal anterior interhemispheric approach. Of the 28 patients, 68% were in poor clinical grade (Hunt and Hess grade III-V) and 89.3% had a Fisher grade III and IV on computed tomography scan. A surgical trajectory about 2 to 3 cm superior to the anterior cranial fossa floor led directly to the aneurysm. Proximal control was achieved before aneurysm dissection and parallel clipping. Results Good outcome (Glasgow Outcome Scale V and IV) was seen in 57.19 of the patients, 14.3% had a poor outcome, and 28.6% died. The cause of death in most patients was found to be a poor clinical grade, postoperative infarct, or presence of multiple aneurysms. Conclusions The advantages of the bifrontal basal anterior interhemispheric approach were the following: ( a) It provided the shortest and a direct trajectory to the aneurysm. ( b) Proximal control of the parent A 2 vessels could be easily achieved. ( c) Release of cerebrospinal fluid from basal cisterns could be done, if necessary. ( d) There was a minimal distortion of or traction over the aneurysm.

CT anatomic features and clinical value of frontal drainage system in chronic frontal sinusitis

目的 探讨慢性额窦炎额窦引流系统CT解剖特征及临床价值.方法对50例慢性鼻窦炎患者应用螺旋CT作横断面扫描,然后经工作站作冠状和矢状面三维重建.结果螺旋CT三维成像技术能清楚地显示钩突附着部位和类型,在100侧钩突中,附着纸样板41侧(41%)、鼻丘后壁11侧(11%)、中鼻甲19侧(19%)、前颅底16侧(16%)、钩突分叉13侧(13%).在额隐窝气房98侧中,终未气房28侧(28.6%)、鼻丘气房18侧(18.4%)、前筛气房18 侧(18.4%).额窦内气房98侧中,其中额气房22侧(22.4%)、眶上气房38侧(38.8%)、额窦中隔气房(M气房)16侧(32%).发现不同类型的解剖变异与慢性炎症的关系.结论慢性额窦炎额窦引流系统CT解剖特征的显示可为术前提供有价值的信息,对开展鼻内镜外科有重要的临床指导意义。

Encephalocoele as a complication of intranasal surgery

Intranasal encephalocoele can be congenital or acquired as a consequence of injury to the floor of anterior cranial fossa disrupting dura resulting in herniation of brain tissue in the nasal cavity. Authors came across a case of encephalocoele as a complication of intranasal polypectoury. We are reporting this case due to its rareness.

Death related to the septorhinoplasty procedure

A 23-year-old lady was referred to a plastic surgeon with complaints of asymmetrical nostrils and a nasal hump. Septorhinoplasty surgery was performed under local anesthesia. After osteotomy and at the end of the operation, she developed unusual bleeding from the site of the operation and her neurologic condition appeared to have worsened, as indicated by deep coma, bilateral pupillary mydriasis, and lack of reflexes. Computed tomography (CT) scan revealed the presence of air within the anterior cranial fossa, an irregular defect in the floor of the anterior cranial fossa, third and fourth ventricular hemorrhage, and subarachnoid hemorrhage in the posterior cranial fossa. Unfortunately, she died on the 7th day of intensive care unit (ICU) admission. Medicolegal autopsy revealed a 2×2 cm crushed region associated with hemorrhage around it in the orbital portion of the left frontal lobe. A fracture of the left cribriform plate of the ethmoid bone was also seen. The patient's death was therefore determined to have been caused by traumatic brain injury and its complications.

A Pitfall in the Diagnosis of Bilateral Choanal Atresia: A Case Report

Choanal atresia is a rare congenital anomaly involving unilateral or bilateral posterior nasal choanal obstruction. Multiple associated anomalies have been described. We describe the case of a 1-month-old boy with bilateral choanal atresia, misdiagnosed after CT as a midline meningocele because the floor of the midline anterior cranial fossa was not ossified and secretion had accumulated in the obstructed posterior nasal choana.

Closure of Recurrent Frontal Skull Base Defects with Vascularized Flaps - A Technical Case Report

Techniques for vascularized reconstruction of the anterior cranial fossa floor defects causing recurrent cerebrospinal fluid fistula are discussed in this report. The closure employs the use of local random- or axial-pattern vascularized flaps in simple cases. In complicated cases (for instance, status after repeated exploration) the tissue of the cranial base is severely compromised and shows low potential for healing. Non-vascularized grafts only add avital scars to the already present ones leading to recurrent fistulas. Free vascularized flaps show more mechanical strength and less scar contraction, resistance to infections and survive better in a compromised surrounding, thus leading to long term sealing in such cases. The technical issues of vascularized closure of defects of the frontal skull base are discussed in this report.

Management of the trochlea of the superior oblique muscle in the repair of orbital roof trauma

Isolated orbital roof fractures are rare (blow-out and blow-in have an equal occurrence), and they generally do not require operative intervention. Typically, patients who undergo orbital roof exploration and repair have concomitant facial fractures and often overlying lacerations or soft tissue crush injuries from high-impact forces. Orbital roof exploration and repair is usually undertaken during the course of managing or repairing dural tears (floor of anterior cranial fossa) or with concomitant fracture repair of the frontal sinus or the skull base. It is important to replace, fix, or reconstruct the orbital roof in these patients to prevent a postoperative pulsatile orbit caused by arterial pulsations and respiratory fluctuations that occur in the overlying cerebral hemisphere. Once the edema has resolved, this is manifested by persistent blurred or double vision.

Craniofacial Resection for Paranasal Sinus Cancer

Paranasal sinus cancer usually presents at an advanced stage to the neurosurgeon, with ethmoid sinus involvement and incipient or actual invasion of the anterior cranial fossa floor; in the past this has usually been associated with a poor prognosis. Our experience with 67 patients using craniofacial resection at the Royal Melbourne Hospital, Australia, between June 1983 and June 1995 has produced a 5-year survival of 80% with no deaths and a low rate of serious complications. This appears to represent a significant improvement in the long-term results compared to conventional surgery and radiotherapy. We believe that a major improvement in tumor control can be achieved using careful surgical techniques, and we place special emphasis on the use of a vascularized pericranial flap in the reconstruction of the floor of the anterior cranial fossa. An overview of paranasal sinus cancer is presented, with particular emphasis on our experience with craniofacial resection for these tumors.