Intradural Transpetrosectomy for Petrous Apex Meningiomas

OBJECTIVE: This study aimed to assess the surgical results of the intradural transpetrosectomy for petrous apex meningiomas (PAMs). In addition, we describe the methods and techniques used to expose and manage superior petrous vein and greater superficial petrosal nerve.METHODS: The authors conducted a retrospective study of 16 patients with PAMs operated by the senior author via the intradural transpetrosectomy between February 2012 to May 2017. We reviewed patient data regarding the general characteristics, surgical technique and surgery-related outcomes and adopted a combined follow-up strategy of clinic and telephone contacts to evaluate postoperative complications.RESULTS: Simpson grade I and II resection was performed in 10 out of 16 cases (62.5%), and grade III resection were reported in the remaining six cases (37.5%) with no resultant mortality. The mean Karnofsky Performance Status score was 85.6 preoperatively and improved to 91.9 postoperatively, with a mean follow-up period of 34.4 months (range, 6–66 months). Tumor recurrence was found in two patients and they underwent the second surgical operation.CONCLUSION: PAMs could be completely resected by the intradural transpetrosectomy with an improved survival rate and postoperative life quality. Superior petrous vein and greater superficial petrosal nerve should be managed properly in avoidance of postoperative complications. Finally, most meningioma inside cavernous sinus or adhered to brainstem could be totally removed without postoperative complications.

Intradural Transpetrosectomy for Petrous Apex Meningiomas

OBJECTIVE: This study aimed to assess the surgical results of the intradural transpetrosectomy for petrous apex meningiomas (PAMs). In addition, we describe the methods and techniques used to expose and manage superior petrous vein and greater superficial petrosal nerve. METHODS: The authors conducted a retrospective study of 16 patients with PAMs operated by the senior author via the intradural transpetrosectomy between February 2012 to May 2017. We reviewed patient data regarding the general characteristics, surgical technique and surgery-related outcomes and adopted a combined follow-up strategy of clinic and telephone contacts to evaluate postoperative complications. RESULTS: Simpson grade I and II resection was performed in 10 out of 16 cases (62.5%), and grade III resection were reported in the remaining six cases (37.5%) with no resultant mortality. The mean Karnofsky Performance Status score was 85.6 preoperatively and improved to 91.9 postoperatively, with a mean follow-up period of 34.4 months (range, 6–66 months). Tumor recurrence was found in two patients and they underwent the second surgical operation. CONCLUSION: PAMs could be completely resected by the intradural transpetrosectomy with an improved survival rate and postoperative life quality. Superior petrous vein and greater superficial petrosal nerve should be managed properly in avoidance of postoperative complications. Finally, most meningioma inside cavernous sinus or adhered to brainstem could be totally removed without postoperative complications.

Petrous bone cholesteatoma: surgery approach and outcomes / 中华耳鼻咽喉头颈外科杂志

Objective@#To investigate the choice of surgical approach of petrous bone cholesteatoma (PBC)and surgical outcomes.@*Methods@#A retrospective study was performed on 90 patients diagnosed and treated for PBC from January 2000 to December 2014 by the Chinese People′s Liberation Army General Hospital otolaryngologists. According to Sanna′s classification, 40 out of the 90 cases were supralabyrinthine, five infralabyrinthine, four infralabyrinthine-apical, 25 massive and 16 apical. Five cases underwent transmastoid and retrolabyrinthine approach, translabyrinthine approach was performed on six patients, 19 cases underwent subtotal petrosectomy, seven cases underwent transotic approach, 41 cases underwent middle fossa approach, combined transmastoid/middle fossa approach was performed on 11 cases, translabyrinthine and sphenoid sinus approach were performed on one case. Supralabyrinthine cases mainly applied middle fossa approach (77.5%, 31/40) and combined transmastoid and middle-fossa approach(20.0%, 8/40). Combined transmastoid-retrolabyrinthine approach were applied for all the infralabyrinthine cases (100.0%, 5/5). Infralabyrinthine-apical cases mainly applied subtotal petrosectomy (75.0%, 3/4). Massive cases mainly applied subtotal petrosectomy (60.0%, 15/25), transcochlear approach (20.0%, 5/25), and translabyrinthine approach (16.0%, 4/25). Apical cases mainly applied middle fossa approach (62.5%, 10/16).@*Results@#Ninty percent (18/20) of the patients who had preoperative grade Ⅰ facial nerve function maintained in the postoperative period. Out of 90 cases, only 11 cases received open cavity, and the rest cases received cavityobliteration. There were three cases of recurrence, four cases of cavity infection, three cases of cerebrospinal fluid leakage, and one case of epidural hematoma, who all received surgeries.@*Conclusions@#Sanna′s classification should be used to classify different kinds of PBC cases, choose the best surgical approach for different cases, and preserve or repair facial function during removal of PBC, and thus reduce recurrence and complications.

Measurement of morphological parameters of internal acousticmeatus using thin-section CT / 中华耳鼻咽喉头颈外科杂志

Objective@#This study aimed to measure the morphological parameters of the internal acoustic meatus(IAM) and its adjacent structures using temporal-bone thin-section CT(computed tomography).@*Methods@#CT images were obtained from 50 Chinese adult patients (25 males and 25 females, 100 sides) which had no visible lesion in the petrous part of the temporal bone and inner ear, the morphological parameters of all inner ear parts were sectionally measured on the specified plane using SPSS 22.0 software for statistical analysis.@*Results@#The integral morphological characteristics of the IAM were observed. These results revealed that anterior-posterior diameter of the internal acoustic poer(IAP)(CD) was (6.93±1.85)mm, the superior-inferior diameter of the IAP(EF) was (4.40±0.86)mm, the length of the IAM(AB) was (9.30±1.60)mm, the superior-inferior diameter of the IAM(the intersection of inner 1/3 section and middle 1/3 section) was (4.13±0.83)mm, the superior-inferior diameter of the IAM(the intersection of middle 1/3 section and outer 1/3 section) was (4.61±1.02)mm, the anterior-posterior diameter of the IAM(the intersection of inner 1/3 section and middle 1/3 section) was (6.62±1.92)mm, the anterior-posterior diameter of the IAM(the intersection of middle 1/3 section and outer 1/3 section) was (6.28±1.65)mm, the depth of transverse crest (superior wall) was (3.10±0.75)mm, the depth of transverse crest (interior wall)the was (1.46±0.59)mm, the distance from transverse crest vertex A to the superior wall of the IAM was (2.05±0.42)mm, the distance from transverse crest vertex A to the interior wall of the IAM was (2.93±0.41)mm, the thickness of the superior bone wall of the IAM (the intersection of inner 1/3 section and middle 1/3 section) was (4.45±1.34)mm, the thickness of the superior bone wall of the IAM (the intersection of middle 1/3 section and outer 1/3 section) was (4.32±1.12)mm, the thickness of the superior bone wall of the IAM (the intersection of outer 1/3 section and transverse crest vertex) was (4.37±1.28)mm, and the appearance ratio of the cells in the whole IAM superior wall was 32%.The whole IAM assumed the shape of short cylinder, inclining about 1 cm outward, with the upper-lower diameter and anterior-posterior diameter about 5 mm.@*Conclusion@#It is necessary for carrying out preoperative the temporal-bone thin-section CT to obtain the morphological parameters of the IAM, determine its basic morphology, and provide references to avoid damaging the other important structures during IAM surgeries.

Osteoplastic Orbitozygomatic-Mastoid-Transattical Craniotomy

Objective The objective of this study is to introduce and describe a surgical technique called Osteoplastic Orbitozygomatic-Mastoid-Transattical Craniotomy (Osteoplastic OZ-MT) and to show the possibility of accomplishing osteoplastic craniotomies for other classical lateral transcranial approaches. Technique The Osteoplastic OZ-MT combines many lateral transcranial approaches. The surgical approach involves structures of lateral and basal portions of the skull, from the frontal bone, superolateral-inferolateral-posterolateral walls of the orbit, zygoma, zygomatic process, sphenoid greater and lesser wings, temporal fossa, mandibular fossa, zygomatic process of the temporal bone, petrous pyramid, mastoid, up to the parietal and occipital regions. The temporal muscle is totally preserved and attached to the one-piece-only bone flap. Results We have developed and used routinely the technique, including its variants and combinations, for about twenty years in children and adults to treat and/or remove mainly mesial, basal, intra, and/or extra-cranium lesions, from the anterior fossa, passing through the middle fossa and going up to the regions of the clivus, basilar artery, and cerebellumpontine angle, with greater surgical degree of freedom and consequent reduction of morbidity and mortality. So far, we have not had any complications nor important sequels, and the aesthetic and functional results are quite favorable. Conclusion The Osteoplastic OZ-MT is a very systematic, anatomical, feasible, and safe craniotomy. The synthesis is easy to do and can be reopened quickly if necessary. Variants and combinations allow us to opt for a more appropriate approach according to each case.

Objetivo Apresentar e descrever uma técnica cirúrgica denominada de Craniotomia Orbitozigomática- Mastóideo-Transatical Osteoplástica (OZ-MT Osteoplástica) e mostrar a possibilidade de realizar craniotomias osteoplásticas para os outros acessos transcranianos laterais clássicos. Técnica A OZ-MT Osteoplástica combina vários acessos transcranianos laterais. O acesso cirúrgico envolve estruturas das porções lateral e basal do crânio, do osso frontal, paredes súperolateral-ínferolateral-pósterolateral da órbita, zigoma, processo zigomático, asas maior e menor do esfenoide, fossa temporal, fossa mandibular, processo zigomático do osso temporal, pirâmide petrosa, mastoide, até as regiões parietal e occipital. O músculo temporal é totalmente preservado e aderido ao retalho ósseo de uma-peça-só. Resultado Temos desenvolvido e usado de rotina a técnica, incluindo suas variantes e combinações, por cerca de vinte anos, em crianças e adultos, para tratar e/ou remover principalmente aquelas lesões mesial, basal, intra e/ou extracranianas, desde a fossa anterior, passando pela fossa média e indo até às regiões do clivus, artéria basilar e ângulo ponto-cerebelar, com maior grau de liberdade cirúrgica e consequente redução da morbidade e mortalidade. Até agora, não tivemos nenhuma complicação e nem sequelas importantes e os resultados estético e funcional são bastantes favoráveis. Conclusões A OZ-MT Osteoplástica é uma craniotomia bastante sistematizada, anatômica, factível e segura. A síntese é fácil de ser feita e que pode ser reaberta rapidamente se necessário. Variantes e combinações nos permitem optar por um acesso mais apropriado conforme cada caso.

Impact of target exposure via retrosigmoidal approach in surgical injury measured by virtual reality skill / 中华神经医学杂志

Objective To discuss the impact of target exposure via retrosigmoidal approach in surgical injury based on virtual reality anatomic models.Methods CT and MR imaging data of 15 adult cadaver heads were utilized to establish three-dimensional anatomy models of petrous bone.Surgical routes exposing different targets though retrosigmoidal approach were simulated by selecting osseous landmark points on the calvaria and skull base.Special form and sequence of anatomic structures in different routes were observed.Volumes of anatomic tissues were measured.Results All the surgical routes passed below the transverse sinus and lateral to the cerebellum.Route a exposed the lower cranial nerve and anterior inferior cerebellar artery;when reached the jugular tubercle,the route exposed inferior petrous sinus.Route b exposed the anterior inferior cerebellar artery,labyrinth and facial-acoustic nerve complex.Route c passed the medial to the superior petrous sinus and exposed the facial-acoustic nerve complex;when being arrived at petrous apex,the route exposed the trigeminal nerve,superior cerebellar artery and cavernous sinus.The volumes of the lower cranial nerve,osseous structures,cerebellum and artery were significantly different in models adopted different routes (P＜0.05);the volume of the lower cranial nerve was as follows:route c＞route a＞route b,the volume of osseous structures was as follows:route c ＞route b＞route a,the volume of cerebellum was as follows:route b ＞route a＞route c,and the volume of artery was as follows:route a ＞route c＞route b.Venous structure involved in route a ([68.91 ±1.91] mm3) was larger than that in route c ([248.92±11.26] mm3) with statistical significance (P＜0.05),and route b did not involve venous structure.Conclusions Targets in skull base has significant impaction on the size of anatomic structures involved in the route of retrosigmoidal approach.Relationship between injury and exposure can be evaluated objectively by the volume measurement.

Anatomical Factors Influencing Pneumatization of the Petrous Apex

OBJECTIVES: Aim of the present study was to define the relationship between petrous apex pneumatization and the nearby major anatomical landmarks using temporal bone computed tomography (CT) images. METHODS: This retrospective, Institutional Review Board-approved study analyzed CT images of 84 patients that showed normal findings bilaterally. Pneumatization of the petrous apex was classified using two methods. Eight parameters were as follows: angle between the posterior cranial fossa and internal auditory canal, Morimitsu classification of anterior epitympanic space, distance between the carotid canal and jugular bulb, distance between the cochlear modiolus and carotid canal, distance between the tympanic segment and jugular bulb, high jugular bulb, distance between the vertical segment and jugular bulb, and distance between the lateral semicircular canals and middle cranial fossa. RESULTS: There was a significant difference in Morimitsu classification of the anterior epitympanic space between the two classification methods. Poorly pneumatic upper petrous apices were distributed uniformly in three types of Morimitsu classification, but more pneumatic upper petrous apices were found more often in anterior type. Lower petrous apex was well pneumatized regardless of the types of anterior epitympanic space, but the largest amount of pneumatization was found more frequently in the anterior type of anterior epitympanic space. CONCLUSION: This study showed that there was no reliable anatomic marker to estimate petrous apex pneumatization and suggests that the pneumatization of the petrous apex may be an independent process from other part of the temporal bone, and may not be influenced by the nearby major anatomical structures in the temporal bone. In this study, the anterior type of anterior epitympanic space was found to be closely related to more well-pneumatized petrous apices, which implies that the anterior saccule of the saccus medius may be the main factor influencing pneumatization of the petrous apex.

Petrositis With Bilateral Abducens Nerve Palsies complicated by Acute Otitis Media

Petrous apicitis is a rare but fatal complication of otitis media. An infection within the middle ear can extend within the temporal bone into the air cells of the petrous apex. With only the thin dura mater separating the trigeminal ganglion and the 6th cranial nerve from the bony petrous apex, they are vulnerable to inflammatory processes, resulting in deep facial pain, lateral rectus muscle paralysis, and diplopia. In 1904, Gradenigo described a triad of symptoms related to petrous apicitis, including acute suppurative otitis media, deep facial pain resulting from trigeminal involvement, and abducens nerve palsy. It has traditionally been treated with surgery, but recent advances in imaging, with improved antibiotic treatment, allow conservative management. In this case report, we describe a clinical and neuroradiological evolution of a child with a petrous apicitis after acute otitis media, which was managed medically with a positive outcome.

Hearing and Facial Function After Surgical Removal of Cholesteatomas Involving Petrous Bone

OBJECTIVES: The purpose of this study was to inspect the clinical characteristics, surgical approaches, functional preservation, and complications of petrous bone cholesteatoma and to propose appropriate surgical approaches based on long-term follow-up cases and previous reports in the literature. METHODS: The medical records of 31 patients who underwent surgery for petrous bone cholesteatoma between 1990 and 2011 at two tertiary referral hospitals were retrospectively analyzed with regard to the classification, type of surgical approach, preservation of facial and auditory function, and recurrence. RESULTS: Of 31 cases, 16 were supralabyrinthine (class I), 1 was infralabyrinthine-apical (class III), 13 were massive (class IV), and 1 was apical (class V). Facial nerve palsy was found in 35.5% of the cases (11 cases). Hearing was preserved in 11 of 22 patients who had better than a 50-dB hearing level of bone conduction pure tone average preoperatively. Preoperative hearing was preserved in only four of the patients in class I (supralabyrinthine). Facial function was preserved or improved in 29 patients (93.5%). CONCLUSION: Complete removal of cholesteatoma of petrous bone can be achieved by choosing the appropriate approach based on location and extent. Facial function was preserved postoperatively in most reviewed cases. Auditory function could not be preserved postoperatively in some cases, but preserving residual hearing levels can be accomplished mostly in supralabyrinthine cholesteatomas with the appropriate surgical approach.

A Case of Petrous Apex Mucocele with Unilateral Ear Fullness Treated with Endoscopic Sphenoid Marsupialization / 대한이비인후과학회지

Mucocele is a benign, encapsulated lesion, lined by epithelium and filled with mucus. Found mostly in the frontal and ethmoid sinus, sinonasal mucoceles cause several symptoms depending on the location. We report a case of mucocele found in the petrous apex that caused ear fullness. It was completely treated with endoscopic sphenoid marsupialization.

Microsurgical management of supra- and infra-tentorial meningioma of the posterior petrous bone / 中国综合临床

Objective To explore the microsurgical experience of supra- and infra-tentorial meningioma of the posterior petrous bone.Methods Clinical data of 21 patients who had undergone microsurgical treatment were retrospectively reviewed.Results All patients underwent surgical treatment via a suboccipital retrosigmoid approach,and hyperostosis of the petrous bone and infiltrated cerebellar tentorium were resected intraoperatively.Tumor resection was categorized as Grade Ⅰ in 16 patients,Grade Ⅱ in 5 patients,according to the Simpson classification system.The main postoperative complications included slight facial paresis and hearing function deterioration.The mean follow-up time was 3.2 years.All patients resumed normal daily activity and no tumor recurrence happened.Conclusions Total resection for supra- and infra-tentorial meningioma of the posterior petrous bone can be achieved with an excellent prognosis by use of microsurgical technique.

Quantitative study of the retrosigmoid suprameatal approach for petrous apex resection LI / 中华神经医学杂志

Objective To evaluate the safety and feasibility of the retrosigmoid suprameatal approach (RSSMA) for petrous apex resection. Methods Ten human dry skull and 18 cadaverie skull specimens were collected and 3-dimensional CT scanning was performed with slice thickness of 1 mm. Craniotomy was performed on the specimens through a modified retrosigmoid approach, and the suprameatal tubercle (ST) and petrous apex (PA) were removed without damaging the trigerninal and facial nerves. The petrous bone was resected to the farthest lateral margin (FLM) that the approach could allow. CT-based and manual measurements were used to determine the lateral-middle line, superior-inferior, anterior-posterior lengths of the ST and PA. The superolateral lip of the internal auditory meatus (SLIAM) was defined as the landmarks for the measurement, and the distances from the SLIAM to the fundus, the common crus, and vestibule was determined. Results From thesuperior-inferior to the anterior-posterior and median-lateral directions, the resection rate of the PA increased to (26.6±6)%, (45±5)%, and (72±6)%, and the rate for the ST to (69±10)%, 100%, and 100%, respectively. The resection rate of the PA at the siphonal portion was (44±7)%. In the RSSMA, the distance from the SLIAM to the FLM (17.6±2.0 mm) was greater than the distances from the SLIAM to the vestibule (10.1±1.4 mm), the fundus (10.4±1.5 mm), and the common crus (10.6±1.1 mm). Conclusions The RSSMA may well protect the siphonal portion of the internal carotid artery from damages in PA resection. The FLM of the RSSMA is always lateral to the vestibule and the fundus of the internal auditory canal and the common crus, and therefore injuries to the vestibule, the semicircular canal and the common crus should be avoided.

Endolymphatic Sac Tumors : Report of Four Cases

Endolymphatic sac tumor is rare, locally aggressive hypervascular tumor of papillary structure, arising from the endolymphatic duct or sac in the posterior petrous bone. We present four cases with this tumor. Two patients were male and the other two were female. Age of each patient was 15, 52, 58, and 67 years. Three patients presented with progressive hearing loss and sustained vertigo for months to years and another one was referred for the tumor detected in routine medical check-up. Preoperative embolization was performed in 3 patients. Complete excision of the tumor was achieved in all patients using translabyrinthine or retrosigmoid approach. Herein, we describe the clinical and radiographic features, surgical treatment and pathologic findings with a review of the literature.

A Case of Petrositis with Abducens Palsy / 대한이비인후과학회지

Petrous apicitis is an extension of infection from the mastoid air cell tract into petrous apex. Petrous apicitis, a potentially fatal complication of suppurative otitis media, presents a variety of symptoms. But the classical findings of petrous apicitis, called Gradenigo's syndrome that include abducens nerve palsy, deep facial pain and acute suppurative otitis media, rarely occur. Gradenigo's syndrome can be treated with surgery, but the advent of antibiotics and early imaging study allow conservative treatment in some uncomplicated cases. With the widespread use of antibiotics, petrous apicitis has become an uncommon disease. So most physicians have little clinical experience in their diagnosis and treatment of this disease. We present a case of Gradenigo's syndrome, which was unresponsive to conservative treatment. We provide here details of our experience of treating the patient with surgery without complication.

MICROSURGICAL TREATMENT OF LARGE PETROCLIVAL CHOLESTEATOMA / 解放军医学杂志

To improve the microsurgical curative effect of petroclival cholesteatoma (PCC), 52 patients harbouring PCC removed from 1993 to 2002 were analyzed retrospectively. Of all patients in this group, total tumor removal was achieved in 47 patients (90%), subtotal removal in 5 (10%). The new cranial nerve injuries occurred postoperatively in 4. Operative death occurred in 1 patient due to severe lung infection (1 9%). The key goal of surgical resection of the tumor was good. Suitable basicranial approaches and skillful microsurgical technique can increase the total removal rate, and decrease its mortality and morbidity.

A Case of Tuberculous Petrositis / 대한이비인후과학회지

Tuberculous petrositis is a very rare disease. It is thought to be developed by a spread of tuberculous infection from the middle ear or pneumatized air cells of mastoid. We report a patient with tuberculous petrositis who complained persistent headache after previous tympanomastoid surgery. The classic symptoms of petrositis (Gradenigo's syndrome) were absent, but the diagnosis of petrositis was made with CT, MRI and Ga-67 citrate scan. Revision surgery including infracochlear drainage of the petrous apex was performed, and the pathologic report revealed a tuberculous infection.

CT and MRI Findings of Congenital Cholesteatoma of Petrous Bone / 实用放射学杂志

Objective To analyze the CT and MRI manifestations of congenital cholesteatoma of petrous bone ,and evaluate the efficacy of it in the clinical practice.Methods Imaging findings in 27 pathological-proved cases were review. Imaging materials included CT scan in 26,MRI scan in 11.Results Petrous bone wall erosion and expanding tumor was observed with CT(n=23),tumor was not oberved with CT(n=3).Congenital choleseatoma signal intensity was intermediate or low on T 1W images and high on T 2W images in 11 cases.Conclusion The role of MRI and CT is affirming in the evaluation of congenital choleseatoma of the petrous bone. MRI is superior to CT for the evaluations of involvement of the membranous labyrinth and intracranial structures.

Malignant(papillary) Meningioma of the Petrous Bone Extending to Cerebellopontine Angle and Infratemporal Fossa: Case Report

The authors present a case of malignant papillary meningioma of the petrous bone involving the whole petrous bone which extended to the left cerebellopontine angle and internal jugular vein extracranially. A 46-year-old male patient was presented with a 3-years history of the left otalgia and subsequent deafness with left facial nerve palsy. Neurological examination revealed a complete palsy of the left eighth nerve, and incomplete palsies of the left 7th, 9th, 11th, and 12th cranial nerves. Magnetic resonance imaging and computerized tomographic scan demonstrate a huge mass in cerebellopontine angle which involved the whole petrous bone, suboccipital bone and internal jugular vein. The tumor was totally resected using the transjugular approach with modified petrous bone resection. Neuropathologic examination revealed a papillary meningioma.

A Case of Thyroid Follicular Carcinoma Metastatic to the Petrous Bone

Among thyroid cancer patients, metastatic skull bone is rare, especially in the skull base region. The authors describe the case of a 42-year-old man with thyroid follicular carcinoma which metastasized to the left petrous bone. During the previous year, the patient had suffered from left tinnitus, hearing loss and peripheral facial nerve palsy; An CT and MRI scans demonstrated severe permeative bone destruction, as well as an enhancing soft tissue mass in the left petrous bone. Left carotid angiography revealed multiple feeding vessels, mainly via the occipital and superior laryngeal artery. The feeders were occluded by intra-arterial embolization with N-butylcyanoacrylate(NBCA). The patient underwent subtotal petrosectomy with near total removal of the tumor, followed by total thyroidectomy. He returned to work one month postoperatively and showed no evidence of recurrence during the follow-up period of seven months.

Primary Rhabdomyosarcoma in Temporal Bone Invading Petrous Bone

The rhabdomyosarcoma(RMS), a leading malignant soft tissue tumor in the pediatric population, occurs most commonly in the craniocervical region. RMS has involved the temporal bone approximately 7% in the literature. Petrous bone invasion was very rare and the overall outcome was always fatal, in spite of the efficacy of multimodality therapy, until recent years. The authors report a case of primary RMS in the temporal bone invading petrous bone and the result of multimodality treatment.