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Sample records for labyrinthectomy petrous apicectomy

  1. Paraganglioma presenting as cholesterol granuloma of the petrous apex.

    PubMed

    Heman-Ackah, Selena E; Huang, Tina C

    2013-09-01

    We report the unique finding of a petrous apex cholesterol granuloma associated with a paraganglioma, also known as a glomus jugulare tumor, in a 52-year-old woman who presented to our department with pulsatile tinnitus, hearing loss, aural fullness, and disequilibrium. She had been treated for a petrous apex cholesterol granuloma 20 years earlier, at which time she had undergone drainage of the granuloma via subtotal petrous apicectomy. When she came to our facility approximately 20 years later, she had signs and symptoms consistent with a jugular paraganglioma, which was likely to have been present at the time of her initial presentation for the cholesterol granuloma. In fact, microscopic bleeding from the paraganglioma might have led to the formation of the cholesterol granuloma. The metachronous presentation of these two entities, which to our knowledge has not been reported previously in the literature, indicates the potential association of paragangliomas with the formation of cholesterol granulomas of the petrous apex.

  2. Neurovestibular Compensation following Ototoxic Lesion and Labyrinthectomy

    PubMed Central

    Yazdanshenas, Hamed; Ashouri, Anousheh; Kaufman, Galen

    2016-01-01

    Introduction Unilateral labyrinthectomy and intra-tympanic gentamycin have been employed in the treatment of Ménière's disease, but the efficacy of these techniques has not been well established. Objective The objective of this study is to measure the time course of recovery from a unilateral labyrinthectomy either after ipsilateral topical treatment with gentamicin to the inner ear or without the previous insult. Methods Twenty-nine adult Mongolian gerbils were randomized into two experimental groups. Group 1 (n = 17) received a right ear gentamicin drug-induced lesion by unilateral labyrinthectomy (UL). Group 2 (n = 12) only received a right unilateral labyrinthectomy lesion. We measured the horizontal vestibulo-ocular responses in gerbils before and after the lesion. The gerbils received an angular acceleration stimulus and their eye movements were recorded. Results The gentamicin lesion resulted in a quicker recovery. Experimental groups underwent a similar time course of recovery. Statistical analysis showed no significant difference between the two groups. Both groups displayed adaptation to the lesion by day 21, but long-term compensation did not completely revert to the original pre-lesion state. Conclusions In a lesion requiring both static and dynamic compensation as in UL, the need for a static compensation may alter pre-existing compensation from a previous dynamic insult and require a new compensation. A previous lesion and adaptation is not preserved for a second lesion and the subject has to re-compensate. Therefore, surgical treatment in Meniere's disease such as UL can be considered without prior gentamicin treatment. Static and dynamic compensations do not appear to be as independent as previous studies have suggested. PMID:27096015

  3. Recovery from unilateral labyrinthectomy in rhesus monkey.

    PubMed

    Fetter, M; Zee, D S

    1988-02-01

    1. We recorded eye movements in six rhesus monkeys before and after unilateral labyrinthectomy and quantified the compensation for both the static and the dynamic disturbances of the vestibuloocular reflex (VOR). 2. When first recorded after labyrinthectomy (18-20 h postlesion), all animals had a spontaneous nystagmus with mean slow-phase velocities ranging from 24 to 54 degrees/s measured in darkness and 0-4 degrees/s measured in the light. The level of nystagmus diminished quickly, and by postoperative day 25 mean values ranged from 4 to 22 degrees/s, measured in darkness. The waveform of individual slow phases was variable, but in the first postoperative week its trajectory usually showed an increasing, or an increasing then decreasing, velocity. This finding indicates that peripheral vestibular lesions can alter the function of the ocular motor eye-position integrator. 3. The VOR gain (eye velocity/head velocity, corrected for spontaneous nystagmus) during rotations (30-300 degrees/s) in the dark was diminished from nearly 1.0 preoperatively to approximately 0.5 when first measured after labyrinthectomy, except for rotations toward the lesioned side at high speeds for which the gain was even lower. Within the first few postoperative days, for rotations toward the intact side, the VOR gain increased rapidly, to approximately 0.8. For rotations toward the lesioned side similar behavior was noted for stimuli of 30-60 degrees/s, but at higher velocities compensation proceeded more slowly. By 3 mo postoperatively gains had reached values ranging from 0.77 to 1.03 for rotations toward the intact side and from 0.61 to 0.98 for rotations toward the lesioned side. Values were higher for lower-velocity stimuli. 4. Caloric testing with ice water in the unoperated ear elicited nystagmus with a mean value of maximum slow-phase velocity of 129 degrees/s preoperatively and 195 degrees/s 3 mo postoperatively. There was no caloric response on the lesioned side. From the

  4. Labyrinthectomy and Vestibular Neurectomy for Intractable Vertiginous Symptoms

    PubMed Central

    Alarcón, Alfredo Vega; Hidalgo, Lourdes Olivia Vales; Arévalo, Rodrigo Jácome; Diaz, Marite Palma

    2017-01-01

    Introduction Labyrinthectomy and vestibular neurectomy are considered the surgical procedures with the highest possibility of controlling medically untreatable incapacitating vertigo. Ironically, after 100 years of the introduction of both transmastoid labyrinthectomy and vestibular neurectomy, the choice of which procedure to use rests primarily on the evaluation of the hearing and of the surgical morbidity. Objective To review surgical labyrinthectomy and vestibular neurectomy for the treatment of incapacitating vestibular disorders. Data Sources PubMed, MD consult and Ovid-SP databases. Data Synthesis In this review we describe and compare surgical labyrinthectomy and vestibular neurectomy. A contrast between surgical and chemical labyrinthectomy is also examined. Proper candidate selection, success in vertigo control and complication rates are discussed on the basis of a literature review. Conclusions Vestibular nerve section and labyrinthectomy achieve high and comparable rates of vertigo control. Even though vestibular neurectomy is considered a hearing sparing surgery, since it is an intradural procedure, it carries a greater risk of complications than transmastoid labyrinthectomy. Furthermore, since many patients whose hearing is preserved with vestibular nerve section may ultimately lose that hearing, the long-term value of hearing preservation is not well established. Although the combination of both procedures, in the form of a translabyrinthine vestibular nerve section, is the most certain way to ablate vestibular function for patients with no useful hearing and disabling vertigo, some advocate for transmastoid labyrinthectomy alone, considering that avoiding opening the subarachnoid space minimizes the possible intracranial complications. Chemical labyrinthectomy may be considered a safer alternative, but the risks of hearing loss when hearing preservation is desired are also high. PMID:28382129

  5. Primate translational vestibuloocular reflexes. IV. Changes after unilateral labyrinthectomy

    NASA Technical Reports Server (NTRS)

    Angelaki, D. E.; Newlands, S. D.; Dickman, J. D.

    2000-01-01

    The effects of unilateral labyrinthectomy on the properties of the translational vestibuloocular reflexes (trVORs) were investigated in rhesus monkeys trained to fixate near targets. Translational motion stimuli consisted of either steady-state lateral and fore-aft sinusoidal oscillations or short-lasting transient displacements. During small-amplitude, steady-state sinusoidal lateral oscillations, a small decrease in the horizontal trVOR sensitivity and its dependence on viewing distance was observed during the first week after labyrinthectomy. These deficits gradually recovered over time. In addition, the vertical response component increased, causing a tilt of the eye velocity vector toward the lesioned side. During large, transient lateral displacements, the deficits were larger and longer lasting. Responses after labyrinthectomy were asymmetric, with eye velocity during movements toward the side of the lesion being more compromised. The most profound effect of the lesions was observed during fore-aft motion. Whereas responses were kinematically appropriate for fixation away from the side of the lesion (e.g., to the left after right labyrinthectomy), horizontal responses were anticompensatory during fixation at targets located ipsilateral to the side of the lesion (e.g., for targets to the right after right labyrinthectomy). This deficit showed little recovery during the 3-mo post-labyrinthectomy testing period. These results suggest that inputs from both labyrinths are important for the proper function of the trVORs, although the details of how bilateral signals are processed and integrated remain unknown.

  6. Cholesterol granuloma and other petrous apex lesions.

    PubMed

    Isaacson, Brandon

    2015-04-01

    This article presents the latest information on the presentation, diagnosis, imaging characteristics, management, and outcomes for petrous apex cholesterol granulomas. An in-depth review of the pathophysiology and surgical approaches is presented along with a summary of other petrous apex lesions and their imaging characteristics.

  7. [Trigeminal neuralgia secondary to petrous endostosis].

    PubMed

    Mata-Gómez, Jacinto; Royano-Sánchez, Manuel; Bejarano-Parra, Macarena; Gilete-Tejero, Ignacio; Rico-Cotelo, María; Ortega-Martínez, Marta

    2017-03-10

    Arterial neurovascular compression is hypothesised to be the main cause of primary trigeminal neuralgia. Although it is the most common cause, other pathologies, such as tumours in the cerebellopontine angle, can cause trigeminal pain. We report a case of a 44-year-old female patient with right trigeminal neuralgia without satisfactory response to medical treatment. Cerebral MRI showed no structural injuries. During microvascular decompression of the trigeminal nerve, endostosis of the internal aspect of the petrous bone was found to compress the trigeminal nerve. The pain disappeared completely in the early postsurgical period, after the complete drilling of the endostosis and microvascular decompression. The patient remains asymptomatic one year later. Endostosis of the petrous bone is a rare cause of trigeminal neuralgia. A proper review of preoperative studies would enable the definitive surgical approach to be optimised.

  8. Congenital cholesteatoma of the petrous pyramid.

    PubMed

    Horn, K L; Shea, J J; Brackmann, D E

    1985-09-01

    A 20-year follow-up was done on a patient with a large congenital cholesteatoma of the petrous apex. The patient was treated successfully with marsupialization through a radical mastoidectomy and sphenoid sinusotomy. Cranial computed tomography and magnetic resonance imaging demonstrated continued cholesteatoma growth. Bone-conduction thresholds remained normal despite replacement of the internal auditory canal by cholesteatoma matrix. The patient continues to have chronic otorrhea, but is otherwise asymptomatic.

  9. Intraosseous Schwannoma of the Petrous Apex.

    PubMed

    Tamura, Ryota; Takahashi, Satoshi; Kohno, Maya; Kameyama, Kaori; Fujiwara, Hirokazu; Yoshida, Kazunari

    2015-07-01

    Background and Importance Intraosseous schwannoma is a relatively rare clinical entity that typically arises in vertebral and mandibular bone. Intraosseous schwannoma located entirely within the petrous bone is exceedingly rare, and only two cases have been reported to date. Clinical Presentation A 47-year-old Asian man was referred to our hospital with a chief complaint of double vision. Neurologic examination revealed left abducens nerve palsy. Radiologic imaging showed a 35-mm osteolytic expansive lesion located in the left petrous apex. We made a preoperative diagnosis of chondrosarcoma and performed surgical resection. Surgery was performed via a left subtemporal epidural approach with anterior petrosectomy. The histopathologic diagnosis of the tumor was schwannoma. Schwannoma arising from cranial nerves was excluded from intraoperative findings in conjunction with the results for cranial nerves, and intraosseous schwannoma was diagnosed. Postoperative course was uneventful, and abducens nerve palsy resolved immediately after surgery. Conclusion The differential diagnosis of intraosseous schwannoma should be considered for an osteolytic mass lesion within the petrous apex. Subcapsular tumor removal was considered ideal in terms of preservation of the cranial nerves and vessels around the tumor.

  10. Cholesterol granuloma of the petrous apex: CT diagnosis

    SciTech Connect

    Lo, W.W.M.; Solti-Bohman, L.G.; Brackmann, D.E.; Gruskin, P.

    1984-12-01

    Cholesterol granuloma of the petrous apex is a readily recognizable and treatable entity that is more common than previously realized. Cholesterol granuloma grows slowly in the petrous apex as a mass lesion until it produces hearing loss, tinnitus, vertigo, and facial twitching. Twelve cases of cholesterol granuloma of the petrous apex are illustrated; ten of these analyzed in detail, especially with respect to CT findings. A sharply and smoothly marginated expansile lesion in the petrous apex, isodense with plain and nonenhancing on CT, is in all probability a cholesterol granuloma. Preoperative recognition by CT is important for planning proper treatment.

  11. Aspergillosis of the Petrous Apex and Meckel's Cave.

    PubMed

    Ederies, Ash; Chen, Joseph; Aviv, Richard I; Pirouzmand, Farhad; Bilbao, Juan M; Thompson, Andrew L; Symons, Sean P

    2010-05-01

    Cranial cerebral aspergillosis is a rare entity in immunocompetent patients. Invasive disease involving the petrous apex and Meckel's cave has rarely been described. We present a case of localized invasive petrous apical and Meckel's cave disease in an immunocompetent patient who presented with hemicranial neuralgic pain.

  12. Petrous apex arachnoid cyst extending into Meckel's cave.

    PubMed

    Batra, Arun; Tripathi, Rajendra Prasad; Singh, Anil Kumar; Tatke, Medha

    2002-09-01

    A rare case of arachnoid cyst involving the petrous apex with an unusual clinical presentation has been described with special emphasis in the imaging features and importance of accurate presurgical diagnosis. Differentiation from the other benign lesions involving the petrous apex and the role of newer MR techniques in the diagnosis of these lesions has been highlighted.

  13. Effectiveness of Submucosal Dexamethasone to Control Postoperative Pain & Swelling in Apicectomy of Maxillary Anterior Teeth

    PubMed Central

    Shah, Shahzad Ali; Khan, Irfanullah; Shah, Humera Shahzad

    2011-01-01

    Purpose The purpose of this study was to evaluate the effect of submucosal dexamethasone injection to control postoperative pain and swelling in apicectomy of maxillary anterior teeth. Methods A randomized, controlled trial comprising 60 adult patients (68.3% male, 31.7% female) with no local or systemic problems was conducted. Patients were randomly divided into two groups: Group A was given 4mg dexamethasone injection perioperatively. Group B (control group) was treated conventionally without any steroid injection. Postoperative pain and swelling was evaluated using a visual analog scale (VAS). Objective measurements of facial pain and swelling were performed daily up to six days postoperatively. Results Dexamethasone group showed significant reduction in pain and swelling postoperatively compared with the control. Conclusion Submucosal dexamethasone 4mg injection is an effective therapeutic strategy for swift and comfortable improvement after surgical procedure and has a significant effect on reducing postoperative pain and swelling. The treatment offers a simple, safe, painless, noninvasive and cost effective therapeutic option for moderate and severe cases. PMID:23267293

  14. Comparing Ancient DNA Preservation in Petrous Bone and Tooth Cementum

    PubMed Central

    Margaryan, Ashot; Stenderup, Jesper; Lynnerup, Niels; Willerslev, Eske; Allentoft, Morten E.

    2017-01-01

    Large-scale genomic analyses of ancient human populations have become feasible partly due to refined sampling methods. The inner part of petrous bones and the cementum layer in teeth roots are currently recognized as the best substrates for such research. We present a comparative analysis of DNA preservation in these two substrates obtained from the same human skulls, across a range of different ages and preservation environments. Both substrates display significantly higher endogenous DNA content (average of 16.4% and 40.0% for teeth and petrous bones, respectively) than parietal skull bone (average of 2.2%). Despite sample-to-sample variation, petrous bone overall performs better than tooth cementum (p = 0.001). This difference, however, is driven largely by a cluster of viking skeletons from one particular locality, showing relatively poor molecular tooth preservation (<10% endogenous DNA). In the remaining skeletons there is no systematic difference between the two substrates. A crude preservation (good/bad) applied to each sample prior to DNA-extraction predicted the above/below 10% endogenous DNA threshold in 80% of the cases. Interestingly, we observe signficantly higher levels of cytosine to thymine deamination damage and lower proportions of mitochondrial/nuclear DNA in petrous bone compared to tooth cementum. Lastly, we show that petrous bones from ancient cremated individuals contain no measurable levels of authentic human DNA. Based on these findings we discuss the pros and cons of sampling the different elements. PMID:28129388

  15. Sixth Nerve Palsy from Cholesterol Granuloma of the Petrous Apex

    PubMed Central

    Roemer, Ségolène; Maeder, Philippe; Daniel, Roy Thomas; Kawasaki, Aki

    2017-01-01

    Herein, we report a patient who had an isolated sixth nerve palsy due to a petrous apex cholesterol granuloma. The sixth nerve palsy appeared acutely and then spontaneously resolved over several months, initially suggesting a microvascular origin of the palsy. Subsequent recurrences of the palsy indicated a different pathophysiologic etiology and MRI revealed the lesion at the petrous apex. Surgical resection improved the compressive effect of the lesion at Dorello’s canal and clinical improvement was observed. A relapsing–remitting sixth nerve palsy is an unusual presentation of this rare lesion. PMID:28261154

  16. Comparative study of dentine permeability after apicectomy and surface treatment with 9.6 microm TEA CO2 and Er:YAG laser irradiation.

    PubMed

    Gouw-Soares, S; Stabholz, A; Lage-Marques, J L; Zezell, D M; Groth, E B; Eduardo, C P

    2004-04-01

    Failure of apicectomies is generally attributed to dentine surface permeability as well as to the lack of an adequate marginal sealing of the retrofilling material, which allows the percolation of microorganisms and their products from the root canal system to the periodontal region, thus compromising periapical healing. The purpose of this study was to evaluate dentine and the marginal permeability after apicectomy and surface treatment with 9.6 micro m TEA CO(2) or Er:YAG 2.94 micro m laser irradiation. Sixty-five single rooted human endodontically treated teeth were divided into five experimental groups: group I (control), apicectomy with high speed bur; group II, similar procedure to that of group I, followed by dentinal surface treatment with 9.6 micro m CO(2) laser; group III, similar procedure to group I followed by dentinal surface treatment with Er:YAG laser 2.94 micro m; group IV, apicectomy and surface treatment with CO(2) 9.6 micro m laser; and group V, apicectomy and surface treatment with Er:YAG laser 2.94 micro m. The analysis of methylene blue dye infiltration through the dentinal surface and the retrofilling material demonstrated that the samples from the groups that were irradiated with the lasers showed significantly lower infiltration indexes than the ones from the control group. These results were compatible with the structural morphological changes evidenced through SEM analysis. Samples from groups II and IV (9.6 micro m CO(2)) showed clean smooth surfaces, fusion, and recrystallized dentine distributed homogeneously throughout the irradiated area sealing the dentinal tubules. Samples from groups III and V (Er:YAG 2.94 micro m) also presented clean surfaces, without smear layer, but roughly compatible to the ablationed dentine and without evidence of dentinal tubules. Through the conditions of this study, the Er:YAG 2.94 micro m and the 9.6 micro m CO(2) laser used for root canal resection and dentine surface treatment showed a reduction of

  17. Functional organization of primate translational vestibulo-ocular reflexes and effects of unilateral labyrinthectomy

    NASA Technical Reports Server (NTRS)

    Angelaki, D. E.; McHenry, M. Q.; Newlands, S. D.; Dickman, J. D.

    1999-01-01

    Translational vestibulo-ocular reflexes (trVORs) are characterized by distinct spatio-temporal properties and sensitivities that are proportional to the inverse of viewing distance. Anodal (inhibitory) labyrinthine stimulation (100 microA, < 2 s) during motion decreased the high-pass filtered dynamics, as well as horizontal trVOR sensitivity and its dependence on viewing distance. Cathodal (excitatory) currents had opposite effects. Translational VORs were also affected after unilateral labyrinthectomy. Animals lost their ability to modulate trVOR sensitivity as a function of viewing distance acutely after the lesion. These deficits partially recovered over time, albeit a significant reduction in trVOR sensitivity as a function of viewing distance remained in compensated animals. During fore-aft motion, the effects of unilateral labyrinthectomy were more dramatic. Both acute and compensated animals permanently lost their ability to modulate fore-aft trVOR responses as a function of target eccentricity. These results suggest that (1) the dynamics and viewing distance-dependent properties of the trVORs are very sensitive to changes in the resting firing rate of vestibular afferents and, consequently, vestibular nuclei neurons; (2) the most irregularly firing primary otolith afferents that are most sensitive to labyrinthine electrical stimulation might contribute to reflex dynamics and sensitivity; (3) inputs from both labyrinths are necessary for the generation of the translational VORs.

  18. Giant Cell Reparative Granuloma of the Petrous Temporal Bone

    PubMed Central

    Williams, Joy C.; Thorell, William E.; Treves, John S.; Fidler, Mary E.; Moore, Gary F.; Leibrock, Lyal G.

    2000-01-01

    Giant cell reparative granuloma (GCRG) is an unusual, benign bone lesion that most commonly affects the maxilla and mandible; skull involvement is rare. The etiology is uncertain but may be related to trauma. GCRG is difficult to distinguish from giant cell tumor of the bone and has a lower recurrence rate. Thirteen reports of temporal bone GCRG in 11 patients have been reported. One report of a petrous GCRG in a 3-year-old girl has been identified. A 38-year-old male presented with a 2-year history of fullness in his left ear, ipsilateral hearing loss, and intermittent cacosmia. Computed tomography and magnetic resonance imaging revealed a large left-sided anterior temporal extradural mass. The patient underwent a left frontotemporal craniotomy and resection of a left temporal fossa tumor that involved the petrous and squamous parts of the temporal bone. The patient's post-operative course was uneventful, except for increased hearing loss secondary to opening of the epitympanum. Follow-up at one month revealed no other problems. Histopathology of the specimen was consistent with a giant cell reparative granuloma. ImagesFigure 1Figure 2p91-aFigure 3 PMID:17171108

  19. Expression of glycine receptors and gephyrin in rat medial vestibular nuclei and flocculi following unilateral labyrinthectomy

    PubMed Central

    Zhou, Wen; Zhou, Liu-Qing; Shi, Hong; Leng, Yang-Ming; Liu, Bo; Zhang, Su-Lin; Kong, Wei-Jia

    2016-01-01

    The medial vestibular nucleus (MVN) and the cerebellar flocculus have been known to be the key areas involved in vestibular compensation (VC) following unilateral labyrinthectomy (UL). In this study, we examined the role of gephyrin and glycine receptor (GlyR) in VC using Sprague-Dawley rats, in an aim to gain deeper insight into the mechanisms responsible for VC. The expression of the α1 and β subunits of GlyR and gephyrin was immunohistochemically localized in rat MVN and flocculi. The mRNA and protein expression of GlyR (α1 and β subunits) and gephyrin was quantitatively determined by RT-qPCR and western blot analysis at 8 h, and at 1, 3 and 7 days following UL. It was found that in the ipsilateral MVN, the mRNA and protein expression of the β subunit of GlyR was significantly increased in comparison to the sham-operated (P<0.01) rats, and in comparison to the contralateral side (P<0.01) at 8 h following UL. In the ipsilateral flocculi, GlyR β protein expression was significantly elevated (P<0.01 for all), as compared to the sham-operated rats at 8 h, and at 1 and 3 days and to the contralateral side 8 h, 1 and 3 days following UL. No significant differences were observed in the mRNA and protein expression of GlyR α1 and gephyrin in the MVN or flocculi between the two sides (ipsilateral and contralateral) in the UL group, and between the sham-operated group and the UL group at any time point. The findings of our study thus suggest that GlyR plays a major role in the recovery of the resting discharge of the deafferented MVN neurons in the central vestibular system. PMID:28026001

  20. Strontium isotope signals in cremated petrous portions as indicator for childhood origin.

    PubMed

    Harvig, Lise; Frei, Karin Margarita; Price, T Douglas; Lynnerup, Niels

    2014-01-01

    Dental enamel is currently of high informative value in studies concerning childhood origin and human mobility because the strontium isotope ratio in human dental enamel is indicative of geographical origin. However, many prehistoric burials involve cremation and although strontium retains its original biological isotopic composition, even when exposed to very high temperatures, intact dental enamel is rarely preserved in cremated or burned human remains. When preserved, fragments of dental enamel may be difficult to recognize and identify. Finding a substitute material for strontium isotope analysis of burned human remains, reflecting childhood values, is hence of high priority. This is the first study comparing strontium isotope ratios from cremated and non-cremated petrous portions with enamel as indicator for childhood origin. We show how strontium isotope ratios in the otic capsule of the petrous portion of the inner ear are highly correlated with strontium isotope ratios in dental enamel from the same individual, whether inhumed or cremated. This implies that strontium isotope ratios in the petrous bone, which practically always survives cremation, are indicative of childhood origin for human skeletal remains. Hence, the petrous bone is ideal as a substitute material for strontium isotope analysis of burned human remains.

  1. Strontium Isotope Signals in Cremated Petrous Portions as Indicator for Childhood Origin

    PubMed Central

    Harvig, Lise; Frei, Karin Margarita; Price, T. Douglas; Lynnerup, Niels

    2014-01-01

    Dental enamel is currently of high informative value in studies concerning childhood origin and human mobility because the strontium isotope ratio in human dental enamel is indicative of geographical origin. However, many prehistoric burials involve cremation and although strontium retains its original biological isotopic composition, even when exposed to very high temperatures, intact dental enamel is rarely preserved in cremated or burned human remains. When preserved, fragments of dental enamel may be difficult to recognize and identify. Finding a substitute material for strontium isotope analysis of burned human remains, reflecting childhood values, is hence of high priority. This is the first study comparing strontium isotope ratios from cremated and non-cremated petrous portions with enamel as indicator for childhood origin. We show how strontium isotope ratios in the otic capsule of the petrous portion of the inner ear are highly correlated with strontium isotope ratios in dental enamel from the same individual, whether inhumed or cremated. This implies that strontium isotope ratios in the petrous bone, which practically always survives cremation, are indicative of childhood origin for human skeletal remains. Hence, the petrous bone is ideal as a substitute material for strontium isotope analysis of burned human remains. PMID:25010496

  2. Simultaneous Labyrinthectomy and Cochlear Implantation for Patients with Single-Sided Ménière's Disease and Profound Sensorineural Hearing Loss

    PubMed Central

    Doobe, G.; Ernst, A.; Ramalingam, R.; Mittmann, P.; Todt, I.

    2015-01-01

    Objective. To investigate the treatment outcome of a simultaneous labyrinthectomy and cochlear implantation in patients with single-sided Ménière's disease and profound sensorineural hearing loss. Study Design. Prospective study. Method. Five patients with single-sided Ménière's disease with active vertigo and functional deafness were included. In all cases, simultaneous cochlear implantation combined with labyrinthectomy surgery was performed. The outcome has been evaluated by the Dizziness Handicap Inventory (DHI) and speech recognition. Results. The combined labyrinthectomy and cochlear implantation led in all patients to a highly significant reduction of dizziness up to a restitutio ad integrum. After activation of the cochlear implant and rehabilitation, a mean monosyllabic speech understanding of 69% at 65 dB was observed. Conclusion. For patients with single-sided Ménière's disease and profound sensorineural hearing loss the simultaneous labyrinthectomy and cochlear implantation are efficient method for the treatment of vertigo as well as the rehabilitation of the auditory system. PMID:26380275

  3. Giant Petrous Bone Cholesteatoma: Combined Microscopic Surgery and an Adjuvant Endoscopic Approach.

    PubMed

    Iannella, Giannicola; Savastano, Ersilia; Pasquariello, Benedetta; Re, Massimo; Magliulo, Giuseppe

    2016-03-01

    Petrous bone cholesteatomas (PBCs) are epidermoid cysts, which have developed in the petrous portion of the temporal bone and may be congenital or acquired. Cholesteatomas arising in this region have a tendency to invade bone and functional structures and the middle and posterior fossae reaching an extensive size. Traditionally, surgery of a giant PBC contemplates lateral transtemporal or middle fossa microscopic surgery; however, in recent years, endoscopic surgical techniques (primary or complementary endoscopic approach) are starting to receive a greater consensus for middle ear and mastoid surgeries. We report the rare case of an 83-year-old Caucasian male affected by a giant cholesteatoma that eroded the labyrinth and the posterior fossa dura and extended to the infralabyrinthine region, going beyond the theca and reaching the first cervical vertebra. The giant cholesteatoma was managed through a combined approach (microscopic and, subsequently, complementary endoscopic approach). In this case report, we illustrate some advantages of this surgical choice.

  4. Giant Petrous Bone Cholesteatoma: Combined Microscopic Surgery and an Adjuvant Endoscopic Approach

    PubMed Central

    Iannella, Giannicola; Savastano, Ersilia; Pasquariello, Benedetta; Re, Massimo; Magliulo, Giuseppe

    2016-01-01

    Petrous bone cholesteatomas (PBCs) are epidermoid cysts, which have developed in the petrous portion of the temporal bone and may be congenital or acquired. Cholesteatomas arising in this region have a tendency to invade bone and functional structures and the middle and posterior fossae reaching an extensive size. Traditionally, surgery of a giant PBC contemplates lateral transtemporal or middle fossa microscopic surgery; however, in recent years, endoscopic surgical techniques (primary or complementary endoscopic approach) are starting to receive a greater consensus for middle ear and mastoid surgeries. We report the rare case of an 83-year-old Caucasian male affected by a giant cholesteatoma that eroded the labyrinth and the posterior fossa dura and extended to the infralabyrinthine region, going beyond the theca and reaching the first cervical vertebra. The giant cholesteatoma was managed through a combined approach (microscopic and, subsequently, complementary endoscopic approach). In this case report, we illustrate some advantages of this surgical choice. PMID:26937334

  5. Primary aneurysmal bone cyst of the petrous temporal bone: A case report and review of literature

    PubMed Central

    Sharma, Mayur; Velho, Vernon; Kharosekar, Hrushikesh

    2016-01-01

    Aneurysmal bone cyst (ABC) arising in the petrous portion of the temporal bone is a rare entity with only five such reported cases in the literature. We report the case of a 28-year-old man who presented with a tender swelling in the right preauricular region with right ear discharge and conductive hearing loss of 4 years' duration. Computed tomography and Magnetic Resonance imaging showed a destructive lesion in the right petrous bone with cavitation consistent with the diagnosis of ABC. Gross total resection of the lesion was achieved and diagnosis was confirmed histologically. The patient had no recurrence at 12 months of follow-up. This report presents the unusual location of an uncommon bony tumor with a review of its clinical, radiological, and histopathological features as well as the treatment modalities available. PMID:27695554

  6. Horizontal vestibuloocular reflex evoked by high-acceleration rotations in the squirrel monkey. III. Responses after labyrinthectomy

    NASA Technical Reports Server (NTRS)

    Lasker, D. M.; Hullar, T. E.; Minor, L. B.; Shelhamer, M. J. (Principal Investigator)

    2000-01-01

    The horizontal angular vestibuloocular reflex (VOR) evoked by high-frequency, high-acceleration rotations was studied in four squirrel monkeys after unilateral labyrinthectomy. Spontaneous nystagmus was measured at the beginning and end of each testing session. During the period that animals were kept in darkness (4 days), the nystagmus at each of these times measured approximately 20 degrees /s. Within 18-24 h after return to the light, the nystagmus (measured in darkness) decreased to 2.8 +/- 1.5 degrees /s (mean +/- SD) when recorded at the beginning but was 20.3 +/- 3.9 degrees /s at the end of the testing session. The latency of the VOR measured from responses to steps of acceleration (3,000 degrees /s(2) reaching a velocity of 150 degrees /s) was 8.4 +/- 0.3 ms for responses to ipsilesional rotations and 7.7 +/- 0.4 ms for contralesional rotations. During the period that animals were kept in darkness after the labyrinthectomy, the gain of the VOR measured during the steps of acceleration was 0.67 +/- 0.12 for contralesional rotations and 0.39 +/- 0.04 for ipsilesional rotations. Within 18-24 h after return to light, the VOR gain for contralesional rotations increased to 0.87 +/- 0.08, whereas there was only a slight increase for ipsilesional rotations to 0.41 +/- 0. 06. A symmetrical increase in the gain measured at the plateau of head velocity was noted after the animals were returned to light. The VOR evoked by sinusoidal rotations of 2-15 Hz, +/-20 degrees /s, showed a better recovery of gain at lower (2-4 Hz) than at higher (6-15 Hz) frequencies. At 0.5 Hz, gain decreased symmetrically when the peak amplitude was increased from 20 to 100 degrees /s. At 10 Hz, gain was decreased for ipsilesional half-cycles and increased for contralesional half-cycles when velocity was raised from 20 to 50 degrees /s. A model incorporating linear and nonlinear pathways was used to simulate the data. Selective increases in the gain for the linear pathway accounted for the

  7. Endoscopic Endonasal Infrapetrous Transpterygoid Approach to the Petroclival Junction for Petrous Apex Chondrosarcoma: Technical Report.

    PubMed

    Maurer, Adrian J; Bonney, Phillip A; Iser, Courtney R; Ali, Rohaid; Sanclement, Jose A; Sughrue, Michael E

    2015-07-01

    Chondrosarcomas of the skull base are rare tumors that present difficult management considerations due to the pathoanatomical relationships of the tumor to adjacent structures. We present the case of a 25-year-old female patient presenting with a chondrosarcoma of the right petrous apex extending inferiorly, medial to the cranial nerves. The tumor was resected via an endoscopic endonasal infrapetrous transpterygoid approach that achieved complete resection and an excellent long-term outcome with no complications. Technical nuances and potential pitfalls of the case are discussed in depth including measures to protect the carotid artery while performing the required drilling of the skull base to access the lesion.

  8. Endoscopic Endonasal Infrapetrous Transpterygoid Approach to the Petroclival Junction for Petrous Apex Chondrosarcoma: Technical Report

    PubMed Central

    Maurer, Adrian J.; Bonney, Phillip A.; Iser, Courtney R.; Ali, Rohaid; Sanclement, Jose A.; Sughrue, Michael E.

    2015-01-01

    Chondrosarcomas of the skull base are rare tumors that present difficult management considerations due to the pathoanatomical relationships of the tumor to adjacent structures. We present the case of a 25-year-old female patient presenting with a chondrosarcoma of the right petrous apex extending inferiorly, medial to the cranial nerves. The tumor was resected via an endoscopic endonasal infrapetrous transpterygoid approach that achieved complete resection and an excellent long-term outcome with no complications. Technical nuances and potential pitfalls of the case are discussed in depth including measures to protect the carotid artery while performing the required drilling of the skull base to access the lesion. PMID:26251785

  9. Recurrent aseptic meningitis as a rare but important presentation of congenital petrous apex cholesteatoma: the value of appropriate imaging

    PubMed Central

    MacKeith, Samuel A; Soledad-Juarez, Maria; Tiberti, Liliana; Orfila, Daniel

    2014-01-01

    We describe the presentation, investigation and challenging management of a young adult with recurrent aseptic meningitis. The presence of cholesterol and triglycerides in the cerebrospinal fluid sample was recognised as a potential sign of an underlying dermoid or epidermoid cyst. We demonstrate how appropriate imaging of the skull base with diffusion-weighted imaging (DWI) MRI can help differentiate between lesions of the petrous apex, facilitating the diagnosis of a petrous apex congenital cholesteatoma/epidermoid cyst. Awareness of this unusual mode of presentation of a rare disease, as well as knowledge of key diagnostic investigations, may allow for earlier identification, treatment and reduced morbidity/mortality. PMID:24614768

  10. Petrous apex cephalocoele: contribution of coexisting intracranial pathologies to the aetiopathogenesis

    PubMed Central

    Duran, S; Hatipoglu, H G; Cılız, D S; Elverici, E; Sakman, B

    2015-01-01

    Objective: The aim of this study was to show the MRI findings of petrous apex cephalocoele (PAC) and the other intracranial pathologies that coexist with PAC, and to discuss the contribution of the co-existing pathologies to aetiopathogenesis. Methods: A retrospective analysis of our imaging archive for the period from January 2012 to October 2013 revealed 13 patients with PAC (12 females and 1 male; age range, 26–69 years). 11 patients underwent MRI examination of the cranium, and 2 patients underwent MRI examination of the sellar region. We evaluated the lesions for content, signal intensity, enhancement, relation to petrous apex and Meckel's cave. Images were also evaluated for coexisting pathologies. Results: The presenting symptoms included headache, vertigo, cerebrospinal fluid (CSF) leak and trigeminal neuropathy. All patients had PAC. All lesions were located posterolateral to the Meckel's cave and were isointense with CSF signal on all pulse sequences. All lesions were continuous with Meckel's cave. Coexisting pathologies included intracranial aneurysmal dilatation, empty sella, mass in hypophysis, arachnoid cyst, inferior herniation of parahippocampal gyrus and optic nerve sheath CSF distension. Conclusion: Coexistence with other intracranial pathologies supports the possibility of CSF imbalance and/or intracranial hypertension in the aetiopathogenesis of PAC. Advances in knowledge: This study examined the contribution of the co-existing intracranial pathologies to the aetiopathogenesis of PAC. PMID:25651410

  11. N-acetyl-L-leucine accelerates vestibular compensation after unilateral labyrinthectomy by action in the cerebellum and thalamus.

    PubMed

    Günther, Lisa; Beck, Roswitha; Xiong, Guoming; Potschka, Heidrun; Jahn, Klaus; Bartenstein, Peter; Brandt, Thomas; Dutia, Mayank; Dieterich, Marianne; Strupp, Michael; la Fougère, Christian; Zwergal, Andreas

    2015-01-01

    An acute unilateral vestibular lesion leads to a vestibular tone imbalance with nystagmus, head roll tilt and postural imbalance. These deficits gradually decrease over days to weeks due to central vestibular compensation (VC). This study investigated the effects of i.v. N-acetyl-DL-leucine, N-acetyl-L-leucine and N-acetyl-D-leucine on VC using behavioural testing and serial [18F]-Fluoro-desoxyglucose ([18F]-FDG)-μPET in a rat model of unilateral chemical labyrinthectomy (UL). Vestibular behavioural testing included measurements of nystagmus, head roll tilt and postural imbalance as well as sequential whole-brain [18F]-FDG-μPET was done before and on days 1,3,7 and 15 after UL. A significant reduction of postural imbalance scores was identified on day 7 in the N-acetyl-DL-leucine (p < 0.03) and the N-acetyl-L-leucine groups (p < 0.01), compared to the sham treatment group, but not in the N-acetyl-D-leucine group (comparison for applied dose of 24 mg i.v. per rat, equivalent to 60 mg/kg body weight, in each group). The course of postural compensation in the DL- and L-group was accelerated by about 6 days relative to controls. The effect of N-acetyl-L-leucine on postural compensation depended on the dose: in contrast to 60 mg/kg, doses of 15 mg/kg and 3.75 mg/kg had no significant effect. N-acetyl-L-leucine did not change the compensation of nystagmus or head roll tilt at any dose. Measurements of the regional cerebral glucose metabolism (rCGM) by means of μPET revealed that only N-acetyl-L-leucine but not N-acetyl-D-leucine caused a significant increase of rCGM in the vestibulocerebellum and a decrease in the posterolateral thalamus and subthalamic region on days 3 and 7. A similar pattern was found when comparing the effect of N-acetyl-L-leucine on rCGM in an UL-group and a sham UL-group without vestibular damage. In conclusion, N-acetyl-L-leucine improves compensation of postural symptoms after UL in a dose-dependent and specific manner, most likely by

  12. N-Acetyl-L-Leucine Accelerates Vestibular Compensation after Unilateral Labyrinthectomy by Action in the Cerebellum and Thalamus

    PubMed Central

    Xiong, Guoming; Potschka, Heidrun; Jahn, Klaus; Bartenstein, Peter; Brandt, Thomas; Dutia, Mayank; Dieterich, Marianne; Strupp, Michael; la Fougère, Christian; Zwergal, Andreas

    2015-01-01

    An acute unilateral vestibular lesion leads to a vestibular tone imbalance with nystagmus, head roll tilt and postural imbalance. These deficits gradually decrease over days to weeks due to central vestibular compensation (VC). This study investigated the effects of i.v. N-acetyl-DL-leucine, N-acetyl-L-leucine and N-acetyl-D-leucine on VC using behavioural testing and serial [18F]-Fluoro-desoxyglucose ([18F]-FDG)-μPET in a rat model of unilateral chemical labyrinthectomy (UL). Vestibular behavioural testing included measurements of nystagmus, head roll tilt and postural imbalance as well as sequential whole-brain [18F]-FDG-μPET was done before and on days 1,3,7 and 15 after UL. A significant reduction of postural imbalance scores was identified on day 7 in the N-acetyl-DL-leucine (p < 0.03) and the N-acetyl-L-leucine groups (p < 0.01), compared to the sham treatment group, but not in the N-acetyl-D-leucine group (comparison for applied dose of 24 mg i.v. per rat, equivalent to 60 mg/kg body weight, in each group). The course of postural compensation in the DL- and L-group was accelerated by about 6 days relative to controls. The effect of N-acetyl-L-leucine on postural compensation depended on the dose: in contrast to 60 mg/kg, doses of 15 mg/kg and 3.75 mg/kg had no significant effect. N-acetyl-L-leucine did not change the compensation of nystagmus or head roll tilt at any dose. Measurements of the regional cerebral glucose metabolism (rCGM) by means of μPET revealed that only N-acetyl-L-leucine but not N-acetyl-D-leucine caused a significant increase of rCGM in the vestibulocerebellum and a decrease in the posterolateral thalamus and subthalamic region on days 3 and 7. A similar pattern was found when comparing the effect of N-acetyl-L-leucine on rCGM in an UL-group and a sham UL-group without vestibular damage. In conclusion, N-acetyl-L-leucine improves compensation of postural symptoms after UL in a dose-dependent and specific manner, most likely by

  13. Hearing preservation in acoustic neuroma resection: Analysis of petrous bone measurement and intraoperative application

    PubMed Central

    Tanrikulu, Levent; Lohse, Peer; Fahlbusch, Rudolf; Naraghi, Ramin

    2016-01-01

    Background: There is an increased risk for labyrinthine injury for the resection of acoustic neuromas (AN) on the suboccipital, retrosigmoid approach. Prognostic factors should be analyzed for the postoperative hearing function. Methods: We examined 51 patients with ANs using preoperative intact hearing function. Audiological data were obtained by pure tone audiogram (PTA) and speech audiogram. The preoperative and postoperative anatomical localization of the labyrinth was measured with specific distances regarding the tumor and corresponding anatomy of the posterior fossa by high-resolution magnetic resonance imaging (MRI). Results: Postoperative MRI controls confirmed no injuries to the labyrinth (0%). The postoperative hearing results showed 100% hearing preservation for T1-tumors (<1 ml/<1.1 cm), 50% for T2-tumors (1–4 ml/1.1–1.8 cm), 40% for T3-tumors (4–8 ml/1.8–2.3 cm) and 18% for T4-tumors (>8 ml/>2.3 cm). Postoperative deafness was seen in all cases with ventral tumor extension higher than 5.5 mm. Postoperative loss of hearing was seen in all cases with hearing preservation with 6–8% of speech discrimination and an increase in the hearing threshold of 12 dB in the PTA compared to the preoperative hearing status. Conclusion: Petrous bone measurement by high-resolution MRI data enables safe surgical exposure of the internal acoustic canal with avoidance of injury to the labyrinth and a better postoperative prognosis, especially for intrameatal ANs and for the resection of intrameatal portions of larger neuromas. The prognostic factors enable the patients and the surgeon a better estimation of postoperative results regarding deafness and postoperative hypacusis and support a consolidated treatment planning. PMID:28144470

  14. Serious myelopathy due to magnetic resonance imaging-occult arteriovenous fistula: Case report of petrous ridge dural arteriovenous fistula

    PubMed Central

    Kim, Hyun Jeong

    2015-01-01

    Background and purpose We present a case of magnetic resonance imaging (MRI)-occult intracranial dural arteriovenous fistula (DAVF) with serious cervical myelopathy and review the pathophysiological background. Summary of case A 61-year-old man had suffered from progressive neurological deterioration. He had demonstrated swollen spinal cord with diffuse enhancement and no dilated vascularity on MRI. Finally, digital subtraction angiography revealed DAVF at the petrous ridge and it was successfully treated by embolization. Conclusion A slow flow DAVF is not readily recognizable on MRI. Whenever a patient presents with unexplainable progressive myelopathy, a possibility of vascular origin has to be considered. PMID:26116647

  15. "Spontaneous" CSF Fistula due to Transtegmental Brain Herniation in Combination with Signs of Increased Intracranial Pressure and Petrous Bone Hyperpneumatization: An Illustrative Case Report.

    PubMed

    Rivera, Diones; Fermin-Delgado, Rafael; Stoeter, Peter

    2014-12-01

    Background and Importance Transtegmental brain herniation into the petrous bone is a rare cause of rhinoliquorrhea. Our case presents a combination of several typical clinical and imaging findings illustrating the ongoing etiologic discussion of such cerebrospinal fluid (CSF) fistulas. Clinical Presentation A 53-year-old man presented with nasal discharge after a strong effort to suppress coughing. Imaging revealed a transtegmental herniation of parts of the inferior temporal gyrus into the petrous bone and in addition a combination of signs of chronically increased intracranial pressure and a hyperpneumatization of the petrous bone. The fistula was closed by a middle cranial fossa approach. Conclusion The case illustrates the two main predisposing factors for development of petrous bone CSF fistulas: increased intracranial pressure and thinning of the tegmental roof due to extensive development of air cells. Because the CSF leakage repair does not change the underlying cause, patients have to be informed about the possibility of developing increased intracranial pressure and recurrences of brain herniations at other sites.

  16. “Spontaneous” CSF Fistula due to Transtegmental Brain Herniation in Combination with Signs of Increased Intracranial Pressure and Petrous Bone Hyperpneumatization: An Illustrative Case Report

    PubMed Central

    Rivera, Diones; Fermin-Delgado, Rafael; Stoeter, Peter

    2014-01-01

    Background and Importance Transtegmental brain herniation into the petrous bone is a rare cause of rhinoliquorrhea. Our case presents a combination of several typical clinical and imaging findings illustrating the ongoing etiologic discussion of such cerebrospinal fluid (CSF) fistulas. Clinical Presentation A 53-year-old man presented with nasal discharge after a strong effort to suppress coughing. Imaging revealed a transtegmental herniation of parts of the inferior temporal gyrus into the petrous bone and in addition a combination of signs of chronically increased intracranial pressure and a hyperpneumatization of the petrous bone. The fistula was closed by a middle cranial fossa approach. Conclusion The case illustrates the two main predisposing factors for development of petrous bone CSF fistulas: increased intracranial pressure and thinning of the tegmental roof due to extensive development of air cells. Because the CSF leakage repair does not change the underlying cause, patients have to be informed about the possibility of developing increased intracranial pressure and recurrences of brain herniations at other sites. PMID:25485224

  17. [Mechanisms of microbial corrosion on petrous materials].

    PubMed

    Gómez-Alarcón, G; de la Torre, M A

    1994-01-01

    Present studies related to stone weathering demonstrate that the biological activity of bacteria, algae, fungi and lichens play an important role in the biodegradative processes implied in stone building decay. In natural environments is not possible to separate the damage provoked by microorganisms from damage caused by physical and chemical agents. In vitro assays carried out with microbes isolated from weathered stones are required in order to understand the biological mechanisms involved in stone deterioration. We have demonstrated, by means of different techniques as commented in the text, that filamentous fungi contribute greatly to stone biodeterioration by using different mechanisms: (a) mechanical (hyphae growth and penetration in stony substrate); and (b) biochemical (organic acid excretion, cation release, chelation and deposition of organic salts, precipitation of neoformation salts and metals oxidation).

  18. Retrosigmoid approach for resection of petrous apex meningioma.

    PubMed

    de Souza, Daniel G; Ditzel Filho, Leo F S; Makonnen, Girma; Zoli, Matteo; Naudy, Cristian; Muto, Jun; Prevedello, Daniel M

    2014-01-01

    We present the case of a 50-year-old female with a 1-year history of right-side facial numbness, as well as an electric shock-like sensation on the right-side of the face and tongue. She was previously diagnosed with vertigo and trigeminal neuralgia. MRI was obtained showing a large right cerebellopontine angle mass. A retrosigmoid approach was performed and total removal was achieved after dissection of tumor from brainstem and cranial nerves IV, V, VI, VII and VIII. Pathology confirmed the diagnosis of a meningioma (WHO Grade I). The patient was discharged neurologically intact on the third postoperative day free of complications. The video can be found here: http://youtu.be/-tR0FtMiUDg .

  19. Sudden hearing loss following non-petrous craniotomy.

    PubMed

    Ryan, J C; Bird, P A; Bonkowski, J A

    2010-01-01

    We present two patients with known otosclerosis undergoing craniotomy for conditions unrelated to the temporal bone who experienced sudden sensorineural hearing loss. In both patients, the hearing loss was noted immediately post-operatively and there was no subsequent recovery. Sudden hearing loss is a rare complication of non-otologic, non-cardiopulmonary bypass surgery. To our knowledge it has not been described in patients with otosclerosis undergoing craniotomy. This is a rare event that may occur in patients with vulnerable ears, such as those with otosclerosis or pre-existing sensorineural hearing loss.

  20. [Malformations and abnormalities of the petrous portion of the temporal bone].

    PubMed

    Reith, W; Yilmaz, U; Heumüller, I

    2014-04-01

    High-resolution computed tomography (HRCT) is the procedure of choice in the diagnostics of abnormalities of the middle and inner ear. It allows a detailed presentation of anatomical features and achieves the prerequisites for selection of the various therapeutic options. The highly diverse abnormalities can be described using detailed imaging analyses. Malformations with an abnormally developed modiolus are assumed to be early embryological defects, such as the classical Mondini dysplasia. The essential therapeutic option for middle ear deformities is still a cochlear implant. The domain of magnetic resonance imaging (MRI) is not only in the analysis of the cochlear nerve and for exclusion of fibrosis or ossification of the labyrinth but is also able to visualize details of isolated malformations, such as an extended vestibular aqueduct or subtle alterations to the vestibule or can visualize them better in comparison to CT. Radiological diagnostics are used not only for classification but also to recognize typical clinical problem situations and play a key role in the diagnostics of hearing disorders and selection of the optimal therapeutic procedure.

  1. Surgical Procedures for Vestibular Dysfunction

    MedlinePlus

    ... using only the opposite ear to maintain balance. Chemical labyrinthectomy A chemical labyrinthectomy is also known as transtympanic or intratympanic ... ear by filling the scala tympani with a chemical solution. Click here to download the "Surgery for ...

  2. Fracture of skull base with delayed multiple cranial nerve palsies.

    PubMed

    Yildirim, Altan; Gurelik, Mustafa; Gumus, Cesur; Kunt, Tanfer

    2005-07-01

    This report describes a pediatric case of delayed glossopharyngeal nerve, vagus nerve, and facial nerve palsies after a head injury. Computed tomography scan of the skull base revealed the fracture of the petrous part of the temporal bone, and the fracture involved the tip of petrous pyramid, in front of the jugular foramen. The anatomical features, mechanisms, diagnosis, and treatment are discussed.

  3. Reappearance of activity in the vestibular neurones of labyrinthectomized guinea-pigs is not delayed by cycloheximide

    PubMed Central

    Ris, Laurence; Wattiez, Ruddy; de Waele, Catherine; Vidal, Pierre-Paul; Godaux, Emile

    1998-01-01

    In mammals, unilateral labyrinthectomy induces an immediate depression of the resting discharges in the neurones of the ipsilateral vestibular nuclei. Later on, a spontaneous restoration of this activity occurs. The aim of the present study was to test the possibility that protein synthesis could be involved in the start of this process in the guinea-pig.Cycloheximide (CHX), a protein synthesis inhibitor, was injected intramuscularly 1 h before (30 mg kg−1) and 5 h after (15 mg kg−1) labyrinthectomy.In a first group of animals, CHX was found to induce an inhibition of protein synthesis at levels ranging from 71 to 93 % for 9 h after labyrinthectomy.In a second group of alert animals, we studied single unit activity of second-order vestibular neurones. It was found that, in the 12–16 h post-labyrinthectomy period, at a time when restoration began in guinea-pigs not treated with CHX, the discharges in the labyrinthectomized group treated with CHX were not different from those observed in a previous study in labyrinthectomized animals not treated with CHX.We conclude that protein synthesis is not required for the start of restoration of activity in the vestibular neurones deprived of their ipsilateral labyrinthine input. PMID:9763641

  4. Gradenigo syndrome: a case report.

    PubMed

    Tutuncuoglu, S; Uran, N; Kavas, I; Ozgur, T

    1993-01-01

    The case is presented of a 13-year-old boy with recurrent episodes of otitis media who developed Gradenigo syndrome. Mastoid and petrous bone involvement were demonstrated by CT. Symptoms resolved with antibiotic treatment.

  5. Trigeminal Neuralgia Due to a Small Meckel's Cave Epidermoid Tumor: Surgery Using an Extradural Corridor.

    PubMed

    Furtado, Sunil V; Hegde, Alangar S

    2009-09-01

    Tumors at the petrous apex are associated with a variety of symptoms, which most often involve the trigeminal nerve. The authors present a rare case of a small epidermoid tumor in Meckel's cave that caused medically refractory trigeminal neuralgia. The surgical challenge associated with approaches to such lesions is discussed. The skull base tumor was excised completely through a small temporal craniotomy. The practicality of neuronavigation in reaching the petrous apex using a small extradural window is presented.

  6. Otolithic Membrane Damage in Patients with Endolymphatic Hydrops and Drop Attacks

    PubMed Central

    Calzada, Audrey P.; Lopez, Ivan A.; Ishiyama, Gail; Ishiyama, Akira

    2012-01-01

    Objectives 1. Evaluate the otolithic membrane in patients with endolymphatic hydrops (EH) and vestibular drop attacks (VDA) undergoing ablative labyrinthectomy. 2. Correlate intraoperative findings to archival temporal bone specimens of patients with EH. Study Design Retrospective case review Setting Tertiary referral center Specimen source 1. Patients undergoing labyrinthectomy for incapacitating Meniere’s disease (MD), delayed EH, VDA, or acoustic neuroma (AN) between 2004 and 2011. 2. Archival temporal bone specimens of patients with MD. Interventions Ablative labyrinthectomy Main outcome measures Examination of the utricular otolithic membrane. Results The otolithic membrane of the utricle was evaluated intraoperatively in 28 patients undergoing labyrinthectomy. 7 (25%) had a history of VDA, 6 (21%) had delayed EH, 9 (32%) had MD, and 6 (21%) had AN. All patients with VDA showed evidence of a disrupted utricular otolithic membrane, whereas only 50% and 56% of patients with delayed EH and MD respectively, demonstrated otolithic membrane disruption (p = 0.051). None of the patients with AN showed otolithic membrane disruption (p = 0.004). The mean thickness of the otolithic membrane in 5 archival temporal bone MD specimens was 11.45 micrometers versus 38 micrometers in normal specimens (p=0.001). Conclusions The otolithic membrane is consistently damaged in patients with VDA. In addition, there is a significantly higher incidence of otolithic membrane injury in patients with MD and delayed EH compared to patients without hydrops, suggesting that the underlying pathophysiology in VDA results from injury to the otolithic membrane of the saccule and utricle, resulting in free-floating otoliths and atrophy. PMID:23064391

  7. Anatomic variation of the abducens nerve in a single cadaver dissection: the "petrobasilar canal".

    PubMed

    Pizzolorusso, Felice; Cirotti, Andrea; Pizzolorusso, Gianfranco

    2017-04-01

    Anatomic variations of the petrosphenoid ligament, Dorello's canal and the course of the abducens nerve have been extensively described over the past years. In the present report of a single cadaver dissection, we describe an unusual course of the abducens nerve at the level of the petrous bone. The right abducens nerve did not enter Dorello's canal, but ran below the petrous bone through a narrow canal in the petrobasilar suture, which we called the "petrobasilar canal". No anatomic variations of the left abducens nerve were noted.

  8. Tuberculoma of the Cavernous Sinus and Meckel's Cave in a Child.

    PubMed

    Kumar, V R Roopesh; Madhugiri, Venkatesh S; Verma, Surendra Kumar; Barathi, S Deepak; Yadav, Awdhesh Kumar; Bidkar, Prasanna

    2013-01-01

    Tuberculous infection of the cavernous sinus and Meckel's cave is extremely rare. In this report, we describe a patient with tuberculoma of the cavernous sinus and Meckel's cave, extending to the petrous apex. The patient underwent microsurgical excision of the lesion and antitubercular chemotherapy resulting in a good outcome. We describe the diagnostic difficulties and review the relevant literature.

  9. Do Parameters Of Irradiation Influences The Apical Sealing Of Er:YAG Laser Apicetomies?

    NASA Astrophysics Data System (ADS)

    Marques, Aparecida Maria Cordeiro; dos Santos, Jean Nunes; Pinheiro, Antonio Luiz Barbosa

    2011-08-01

    Failures on the sealing of the tooth apex are responsible for many failures of apical surgeries. The Er:YAG laser has been proposed as an alternative for the use of rotator instruments on surgical endodontics. 12 human extracted canines had root endodontic treatment being the apical limit was set at 1mm before the apical foramen and were distributed into 2 groups. On group I, apicectomy was performed with the Er:YAG laser (250 mJ/15 Hz). Apical cut was performed of perpendicular mode with 3mm from the apical foramen. On Group II, the same procedures and the same sequence as above was used, varying only the parameters of the Er:YAG laser (400 mJ/6 Hz). The specimens were divided into groups and fixed, by the cervical third, on wax. Impermeabilization of the residual root apical third was performed following the same procedures used in the cervical third but the residual apex was left free from the impermeabilization. After that, the roots were immersed in a 2% methylene blue solution and placed in a bacteriological oven for 48 h. The segments were visually observed and the one showing greatest level of dye leakage was selected and kept in individual container and coded accordingly. Apical staining was measured using a stereoscopic magnifying glass; a compass; and caliper. The results showed that Group I showed significantly different higher mean level of dye leakage (5.67±4.9, p<0.05). There was a significantly difference between the groups. It is concluded that the apicectomies carried out with 400 mJ/6 Hz showed the smallest infiltration value.

  10. Effect of physical exercise prelabyrinthectomy on locomotor balance compensation in the squirrel monkey

    NASA Technical Reports Server (NTRS)

    Igarashi, M.; Ohashi, K.; Yoshihara, T.; MacDonald, S.

    1989-01-01

    This study examines the effectiveness of physical exercise, during a prepathology state, on locomotor balance compensation after subsequent unilateral labyrinthectomy in squirrel monkeys. An experimental group underwent 3 hr. of daily running exercise on a treadmill for 3 mo. prior to the surgery, whereas a control group was not exercised. Postoperatively, the locomotor balance function of both groups was tested for 3 mo. There was no significant difference in gait deviation counts in the acute phase of compensation. However, in the chronic compensation maintenance phase, the number of gait deviation counts was fewer in the exercise group, which showed significantly better performance stability.

  11. Vestibular-related neuroscience and manned space flight

    NASA Technical Reports Server (NTRS)

    Igarashi, Makoto

    1988-01-01

    The effects of weightlessness on the human vestibular system are examined, reviewing the results of recent investigations. The functional, neurophysiological, and neurochemical changes which occur during adaptation to weightlessness are discussed; theoretical models proposed to explain the underlying mechanism are outlined; and particular attention is given to the author's experiments on squirrel monkeys. There, good correlations were found between (1) the recovery of locomotor balance function in the acute compensation phase after unilateral labyrinthectomy and (2) the bilateral imbalance in the optical density of GABA-like immunoreactivity.

  12. Influence of vestibular input on spatial and nonspatial memory and on hippocampal NMDA receptors.

    PubMed

    Besnard, S; Machado, M L; Vignaux, G; Boulouard, M; Coquerel, A; Bouet, V; Freret, T; Denise, P; Lelong-Boulouard, V

    2012-04-01

    It has recently been shown that a lack of vestibular sensory information decreases spatial memory performance and induces biochemical changes in the hippocampus in rodents. After vestibular neurectomy, patients display spatial memory deficit and hippocampal atrophy. Our objectives were to explore: (a) spatial (Y maze, radial-arm maze), and non-spatial (object recognition) memory performance, (b) modulation of NMDA receptors within the hippocampus using radioligand binding, and (c) hippocampal atrophy, using MRI, in a rat model of bilateral labyrinthectomy realized in two operations. Chemical vestibular lesions (VLs) were induced in 24 animals by transtympanic injections of sodium arsanilate (30 mg/0.1 ml/ear), one side being lesioned 3 weeks after the other. The control group received transtympanic saline solution (0.1 ml/ear) (n = 24). Spatial memory performance (Y maze and radial maze) decreased after VL. Conversely, non-spatial memory performance (object recognition) was not affected by VL. No hippocampal atrophy was observed with MRI, but density of NMDA receptors were increased in the hippocampus after VL. These findings show that the lack of vestibular information induced specific deficits in spatial memory. Additionally, quantitative autoradiographic data suggest the involvement of the glutamatergic system in spatial memory processes related to vestibular information. When studying spatial memory performances in the presence of vestibular syndrome, two-step labyrinthectomy is a suitable procedure for distinguishing between the roles of the specific components of vestibular input loss and those of impaired locomotor activity.

  13. Cochlin expression in vestibular endorgans obtained from patients with Meniere's disease.

    PubMed

    Calzada, Audrey P; Lopez, Ivan A; Beltran Parrazal, Luis; Ishiyama, Akira; Ishiyama, Gail

    2012-11-01

    The distribution of cochlin and its associated basement membrane proteins (collagen IV, collagen II, laminin-β2, and nidogen-1) were evaluated in the vestibular endorgans of subjects with Meniere's disease and compared with normal specimens. Cochlin mRNA expression in vestibular endorgans from Meniere's disease specimens was also investigated. Specimens were obtained from patients who had Meniere's disease and who were undergoing ablative labyrinthectomy. Control specimens were obtained both from autopsy specimens with documented normal audiovestibular function and from patients undergoing labyrinthectomy for acoustic neuroma excision. In the normal control specimens, cochlin immunoreactivity was found evenly distributed in the stroma of the cristae ampullaris and maculae of the utricle. In Meniere's specimens, cochlin immunoreactivity was markedly increased; this was associated with an increase in cochlin mRNA expression as shown by real-time reverse transcription with the polymerase chain reaction. Collagen IV and laminin-β2 immunoreactivity was significantly decreased in Meniere's specimens. Nidogen-1 and collagen II immunoreactivity was unchanged in Meniere's specimens when compared with normal samples. Cochlin upregulation has been implicated in the hereditary audiovestibulopathy, DFNA9. The increased expression of cochlin and decreased expression of collagen IV and laminin in Meniere's disease are suggestive that the overexpression of cochlin contributes to the dysfunctional inner ear homeostasis seen in this disease.

  14. Sexual dimorphism of the lateral angle of the internal auditory canal and its potential for sex estimation of burned human skeletal remains.

    PubMed

    Gonçalves, David; Thompson, Tim J U; Cunha, Eugénia

    2015-09-01

    The potential of the petrous bone for sex estimation has been recurrently investigated in the past because it is very resilient and therefore tends to preserve rather well. The sexual dimorphism of the lateral angle of the internal auditory canal was investigated in two samples of cremated Portuguese individuals in order to assess its usefulness for sex estimation in burned remains. These comprised the cremated petrous bones from fleshed cadavers (N = 54) and from dry and disarticulated bones (N = 36). Although differences between males and females were more patent in the sample of skeletons, none presented a very significant sexual dimorphism, thus precluding any attempt of sex estimation. This may have been the result of a difficult application of the method and of a differential impact of heat-induced warping which is known to be less frequent in cremains from dry skeletons. Results suggest that the lateral angle method cannot be applied to burned human skeletal remains.

  15. Artifacts produced during electrical stimulation of the vestibular nerve in cats. [autonomic nervous system components of motion sickness

    NASA Technical Reports Server (NTRS)

    Tang, P. C.

    1973-01-01

    Evidence is presented to indicate that evoked potentials in the recurrent laryngeal, the cervical sympathetic, and the phrenic nerve, commonly reported as being elicited by vestibular nerve stimulation, may be due to stimulation of structures other than the vestibular nerve. Experiments carried out in decerebrated cats indicated that stimulation of the petrous bone and not that of the vestibular nerve is responsible for the genesis of evoked potentials in the recurrent laryngeal and the cervical sympathetic nerves. The phrenic response to electrical stimulation applied through bipolar straight electrodes appears to be the result of stimulation of the facial nerve in the facial canal by current spread along the petrous bone, since stimulation of the suspended facial nerve evoked potentials only in the phrenic nerve and not in the recurrent laryngeal nerve. These findings indicate that autonomic components of motion sickness represent the secondary reactions and not the primary responses to vestibular stimulation.

  16. Interpositional carotid artery bypass strategies in the surgical management of aneurysms and tumors of the skull base.

    PubMed

    Liu, James K; Couldwell, William T

    2003-03-15

    Cerebral revascularization is an important component in the surgical management of complex skull base tumors and aneurysms. Patients who harbor complex aneurysms that cannot be clipped directly and in whom parent vessel occlusion cannot be tolerated may require cerebrovascular bypass surgery. In cases in which skull base tumors encase the carotid artery (CA) and a resection is desired, a cerebrovascular bypass may be necessary in planned CA occlusion or sacrifice. In this review the authors discuss options for performing high-flow anterograde interposition CA bypass for lesions of the skull base. The authors review three important bypass techniques involving saphenous vein grafts: the cervical-to-petrous internal carotid artery (ICA), petrous-to-supraclinoid ICA, and cervical-to-supraclinoid ICA bypass. These revascularization techniques are important tools in the surgical treatment of complex aneurysms and tumors of the skull base and cavernous sinus.

  17. [Use of the ISG viewing wand on the temporal bone. A model study].

    PubMed

    Vogele, M; Freysinger, W; Bale, R; Gunkel, A R; Thumfart, W F

    1997-02-01

    Surgical interventions in the petrous bone have to be performed in close relationship to vital and delicate anatomical structures. In cases of revision surgery or with massive pathological changes 3D computer-assisted navigation provides an essential tool for preoperative planning, definition of target structures and intraoperative orientation. This technology can help to diminish intraoperative risks for the patient and may help to optimize any microsurgery. In this report we present our first experiences in using the ISG Viewing Wand in the petrous bone through a specially designed model. By recording more than 4000 single measurements we found that the ISG Viewing Wand can be used with sufficient precision. We have now outlined the most important conditions necessary for possible application to a patient.

  18. [A caloric vestibular test with increased positive evidence (author's transl)].

    PubMed

    Kurzeja, A; Strauss, P; Kapell, H

    1979-12-01

    A decrease of the variance of a caloric test would increase the importance of the statement of this test. An important source of variance are the differences concerning the timecourse of the induced heat wave, determined by the different anatomic conditions in the petrous bone, particularly the pneumatisation. A constant temperature gradient is obtained by the irigation in a pessimum position with the head flexed 30 degrees to the front. This temperature gradient evokes immediately a constant maximum vestibular stimulus after having reflected the head 90 degrees to the back. Comparing this new method with the traditional irrigation, one can state an important reduction of variance. The dependence of the nystagumus response on caloric irrigation of the petrous bone demands a X-ray-examination according to the technique of Schüller before starting with the caloric examination. In case of differences between the right and left sides the described test would be necessary in our opinion.

  19. Dissociations between behavioural recovery and restoration of vestibular activity in the unilabyrinthectomized guinea-pig.

    PubMed Central

    Ris, L; Capron, B; de Waele, C; Vidal, P P; Godaux, E

    1997-01-01

    1. In the guinea-pig, a unilateral labyrinthectomy induces postural disturbances and an ocular nystagmus which abate or disappear over time. These behavioural changes are accompanied by an initial collapse and a subsequent restoration of the spontaneous activity in the neurones of the ipsilateral vestibular nuclei. Recently, it has been shown that the vestibular neuronal activity remained collapsed over at least 10 h whereas its restoration was complete 1 week after the lesion. The aims of this study were to determine when restoration of spontaneous activity in the partially deafferented vestibular neurones started and to compare the time courses of the behavioural and neuronal recoveries in guinea-pigs that had undergone a unilateral labyrinthectomy. 2. Neuronal discharge measurements were made using chronic extracellular recording of single unit activity. After a left labyrinthectomy, electrodes, were placed on the site of the destroyed labyrinth to enable stimulation of the left vestibular nerve. Behavioural measurements included chronic recording of eye movements by the scleral search coli technique. After a left labyrinthectomy, lateral deviation of the head, twisting of the head, and eye velocity of the slow phases of the nystagmus were measured. 3. The neuronal activity of the rostral part of the vestibular nuclear complex on the lesioned side was recorded in alert guinea-pigs over 4 h recording sessions between 12 and 72 h after the lesion. 4. The criterion used to select vestibular neurones for analysis was their recruitment by an electric shock on the vestibular nerve. In addition, in order to explore a uniform population, we focused on neurones recruited at monosynaptic latencies (0.85-1.15 ms). 5. For each recording period, the mean resting rate was calculated animal by animal and the grand mean of these individual resting rate means was calculated. Previously, a decline in the grand mean resting rate from 35.8 +/- 6.0 spikes s-1 (control state) to 7

  20. CT appearances of external ear canal cholesteatoma.

    PubMed

    Malcolm, P N; Francis, I S; Wareing, M J; Cox, T C

    1997-09-01

    External ear canal cholesteatoma (EECC) is rare in ear, nose and throat (ENT) practice. Two cases, one bilateral, are described. Computed tomography demonstrates the extent of bony involvement. Erosion of the external canal should not be overlooked when reviewing CT of the petrous bone in cases of discharge from the ear. EECC may necessitate surgery and delay in the diagnosis of EECC can result in progressive bony destruction.

  1. [Basilar impression as a cause of trigeminal neuralgia: report of a case].

    PubMed

    da Silva, J A; da Silva, E B

    1982-06-01

    A case of basilar impression associated with Arnold-Chiari malformation and with trigeminal neuralgia is reported. The radiological examination of the skull showed marked asymmetry of the petrous bone with the tip of the odontoid apophysis located 30 mm above the McGregor line. Treatment consisted of craiectomy of the posterior fossa and cervical laminetomy (C1 to C3). The postoperative course was uneventful with total disappearance of the trigeminal neuralgia.

  2. Modeling the Biodynamical Response of the Human Head for Injury Analysis

    DTIC Science & Technology

    2001-09-01

    cranial bones include the occipital bone, two parietal bones, frontal bone, two temporal bones, sphenoid bone, and ethmoid bone [13,22]. The...attachment. The petrous portion is very dense and hard and is located at the base of the skull between the occipital and sphenoid bones. The interior...surface forms the base of the rear portion of the middle fossa and the front portion of the posterior fossa [13]. The sphenoid bone, well known for

  3. Potential of the navigated controlled surgery at the lateral skull base with the navigated control unit (NCU 2.0).

    PubMed

    Hofer, Mathias; Lueth, Tim; Dietz, Andreas; Strauss, Gero

    2012-01-01

    Segmentation for navigated control was in the first generation very time consuming. In the present version (NCU 2.0) the risk structure is segmented (instead of the work space), this leads to an enormous decrease in preparation time. In additional, new safety functions were integrated. The segmentation feasibility was tested on patient data and proved to be successful. The automatic stop function was tested on petrous bone models and showed no damage to the facial nerve.

  4. [Vertigo induced by noise or pressure to the left ear].

    PubMed

    Seidel, D U; Dülks, A; Remmert, S

    2011-06-01

    A 49-year-old male patient presented with recently acquired vertigo induced by noise or pressure to the left ear. With appropriate stimulation, oscillopsia with a rotatory component could be reproduced in videooculography. Cervical vestibular evoked myogenic potentials (VEMP) showed increased amplitudes and a lowered threshold on the left side. CT of the petrous bone showed a bony dehiscence of the left superior semicircular canal. Conservative therapy was initiated as a first step.

  5. Extradural Dermoid Cyst of the Anterior Infratemporal Fossa. Case Report

    PubMed Central

    Watanabe, Kentaro; Filomena, Carol A.; Nonaka, Yoichi; Matsuda, Masahide; Zomorodi, Ali R.; Friedman, Allan H.; Fukushima, Takanori

    2015-01-01

    Dermoid cysts are rare in the skull base. There have been 10 reported cases of dermoid cysts in the cavernous sinus, two in the petrous apex, and one in the extradural Meckel cave. This is the first case report of a dermoid cyst in the anterior infratemporal fossa attached to the anterior dura of the foramen ovale. The clinical presentation, radiologic findings, histologic features, tumor origin, and operative technique are described along with a review of the literature. PMID:26623226

  6. Epidermoid tumor within Meckel's cave--case report.

    PubMed

    Nadkarni, T; Dindorkar, K; Muzumdar, D; Goel, A

    2000-01-01

    A rare case of an epidermoid tumor lying within Meckel's cave is reported. A 27-year-old housewife presented with complaints of right facial hypesthesia for two and a half years. On examination she had partial loss of touch sensation in the right trigeminal nerve distribution. Magnetic resonance imaging revealed a tumor located at the right petrous apex and cavernous sinus. The epidermoid tumor was excised through a lateral basal subtemporal approach. The symptoms resolved following surgery.

  7. Cremated human remains: is measurement of the lateral angle of the meatus acusticus internus a reliable method of sex determination?

    PubMed

    Masotti, Sabrina; Succi-Leonelli, Elisa; Gualdi-Russo, Emanuela

    2013-09-01

    The purpose of this study was to evaluate the lateral angle (LA) method-based on the measurement of the angle at which the internal acoustic canal opens up to the surface of the petrous bone-for sex determination in cremated skeletal remains of Italians. The sample consisted of 160 adult individuals of known age and sex who had recently died and were cremated in the crematorium of Ferrara (northern Italy). Several studies have demonstrated that the petrous portion of the temporal bone may be a valuable tool for sex diagnosis in unburned skeletal remains. Since petrous bones are usually preserved after cremation, this method could be of particular interest in the case of burned skeletal remains. The repeatability of intra- and inter-observer measurements was good. The results indicated that male and female lateral angles were significantly different but that the values did not differ among age-groups. There was no bilateral difference in LA. However, neither the 45° angle, proposed in earlier studies as the sectioning point for this variable from male and female data distributions, nor another angular value allowed satisfactory discrimination between the sexes in our sample. The influence of the "age" factor (about 82 % of females were of ≥ 75 years of age) on the results is critically discussed. The results of this study suggest that the LA method is not sufficiently reliable to assess the sex of elderly Italian individuals from their burned remains and thus should only be used in conjunction with other sexing techniques.

  8. Subtemporal-anterior transtentoral approach to middle cranial fossa microsurgical anatomy.

    PubMed

    Xu, Zhiming; Wang, Weimin; Zhang, Jingjing; Liu, Wei; Feng, Yugong; Li, Gang

    2014-11-01

    This study aimed to describe the topography of inferior and external dura mater of the middle cranial fossa through subtemporal-anterior transpetrosal approach and discuss the feasibility of improving the approach. Eight formalin-fixed adult cadaveric heads were studied, with the bones milled away in the lateral triangle region of the petrous bone, Kawase rhombus region, and inner triangle region of the petrous apex. The distances between the targets in these regions, as well as the angles after the dissection of zygomatic arch, were measured, and then the exposed petroclival and retrochiasmatic areas were observed under the microscope. There were significant variations in the distances between targets in the 3 milled regions among the specimens. After the dissection of zygomatic arch, the surgical view got an average increase of 12 degrees. The subtemporal anterior transpetrosal approach, as an improved subtemporal approach, can expose the lesions optimally, causing no injury to the hearing and reducing injuries to temporal lobe. On the other hand, the lateral bone of the petrous parts of the temporal bone is removed so as to improve the view to the retrochiasmatic area and expand the operative field.

  9. Anatomical study of the cavernous sinus emphasizing operative approaches and related vascular and neural reconstruction.

    PubMed

    Sekhar, L N; Burgess, J; Akin, O

    1987-12-01

    The efficacy of three operative approaches to the cavernous sinus (CS) and the possibilities of vascular and cranial nerve reconstruction in and around the CS were studied in 50 cadaver specimens (25 heads). The lateral operative approach was through the lateral wall, between Cranial Nerves V1 and IV, or between Cranial Nerves V1 and V2. The superior approach was through the superior wall of the CS after removing the anterior clinoid process and unroofing the optic canal. The inferior approach followed the petrous internal carotid artery (ICA) into the CS after an extradural subtemporal exposure or after a combined subtemporal and infratemporal fossa exposure. The different exposures of the spaces of the CS and of the intracavernous structures provided by the superior and the lateral approaches were complementary. The exposure provided by the inferior approach was minimal; however, the junction of the petrous and cavernous ICA was best exposed by this route. The combined subtemporal and infratemporal fossa approach exposed the petrous ICA (for proximal control or for reconstruction) with the greatest ease and with the least temporal lobe retraction. The combination of the superior and lateral approaches and the complete mobilization of the intracavernous ICA facilitated its repair after experimental lacerations. Lacerations of either the inferior and the inferomedial aspects of any portion of the cavernous ICA or of the anterior surface of the posterior vertical segment of the artery were the most difficult to repair. End-to-end anastomosis was more difficult with the posterior third of the artery than with the anterior two-thirds. A vein graft with an average length of 3.5 cm could be sutured from the petrous to the supraclinoid ICA to bypass the cavernous ICA, with an average occlusion time of 45 minutes. End-to-end technique was judged better for the proximal anastomosis, but end (graft)-to-side anastomosis was easier to perform at the distal end because of the

  10. Risk of bleeding after dentoalveolar surgery in patients taking anticoagulants.

    PubMed

    Broekema, Ferdinand I; van Minnen, Baucke; Jansma, Johan; Bos, Rudolf R M

    2014-03-01

    To avoid increasing the risk of thromboembolic events, it is recommended that treatment with anticoagulants should be continued during dentoalveolar operations. We have evaluated the incidence of bleeding after dentoalveolar operations in a prospective study of 206 patients, 103 who were, and 103 who were not, taking anticoagulants. Seventy-one were taking thrombocyte aggregation inhibitors and 32 vitamin K antagonists. Patients were treated according to guidelines developed at the Academic Centre for Dentistry Amsterdam (ACTA), The Netherlands. The operations studied included surgical extraction (when the surgeon had to incise the gingiva before extraction), non-surgical extraction, apicectomy, and placement of implants. Patients were given standard postoperative care and those taking vitamin K antagonists used tranexamic acid mouthwash postoperatively. No patient developed a severe bleed that required intervention. Seven patients (7%) taking anticoagulants developed mild postoperative bleeds. Patients taking vitamin K antagonists reported 3 episodes (9%) compared with 4 (6%) in the group taking thrombocyte aggregation inhibitors. Among patients not taking anticoagulants, two (2%) developed mild bleeding. The differences between the groups were not significant. All bleeding was controlled by the patients themselves with compression with gauze. We conclude that dentoalveolar surgery is safe in patients being treated with anticoagulants provided that the conditions described in the ACTA guidelines are met.

  11. Sealing ability of MTA and radiopaque Portland cement with or without calcium chloride for root-end filling.

    PubMed

    Bortoluzzi, Eduardo Antunes; Broon, Norberto Juárez; Bramante, Clovis Monteiro; Garcia, Roberto Brandão; de Moraes, Ivaldo Gomes; Bernardineli, Norberti

    2006-09-01

    The aim of this study was to evaluate the influence of calcium chloride (CaCl(2)) on the sealing ability of three Mineral Trioxide Aggregate (MTA) cements, ProRoot MTA, MTA-Angelus, and radiopaque White Portland cement (WPC), for retrograde root filling. Seventy roots of extracted single-rooted teeth were instrumented and obturated. After sectioning the samples at 2 mm from the apex, they received one layer of Araldite and two coats of nail enamel, except for the apical dentinal surface submitted to apicectomy. Standardized retrograde cavities were prepared, filled with one of the materials, and immersed in 0.2% Rhodamine B solution for 72 hours. Dye leakage was analyzed on a light microscope with ocular micrometer. Kruskal-Wallis and Miller tests were used to compare groups arranged in increasing order of leakage, according to mean rank of scores: WPC+CaCl(2), MTA-Angelus+CaCl(2), ProRoot MTA+CaCl(2), MTA-Angelus, ProRoot MTA, and WPC. CaCl(2) improved the sealing ability of all three MTA cements.

  12. Changes of some amino acid concentrations in the medial vestibular nucleus of conscious rats following acute hypotension.

    PubMed

    Li, Xiang-Lan; An, Ying; Jin, Qing-Hua; Kim, Min Sun; Park, Byung Rim; Jin, Yuan-Zhe

    2010-06-14

    Microdialysis and high performance liquid chromatography (HPLC) were used to measure the changes of certain amino acids in the medial vestibular nucleus (MVN) of conscious rats in order to understand whether those amino acids are involved in the regulation of blood pressure. Acute hypotension was induced by infusing sodium nitroprusside (SNP) into the femoral vein. In the control group, glutamate (Glu) release increased, though gamma-aminobutyric acid (GABA) and taurine (Tau) release decreased in the MVN following acute hypotension. In the unilateral labyrinthectomy group, the levels of Glu, GABA, and Tau were unchanged in the ipsilateral MVN to the lesion following acute hypotension. Furthermore, in the contralateral MVN to the lesion, Glu release increased, and GABA and Tau release decreased following acute hypotension. These results suggest that SNP-induced acute hypotension can influence the activity of neurons in the MVN through afferent signals from peripheral vestibular receptors, and that certain amino acid transmitters in the MVN are involved in this process.

  13. The effects of area postrema lesions and selective vagotomy on motion-induced conditioned taste aversion

    NASA Technical Reports Server (NTRS)

    Fox, Robert A.; Sutton, R. L.; Mckenna, Susan

    1991-01-01

    Conditioned taste aversion (CTA) is one of several behaviors which was suggested as a putative measure of motion sickness in rats. A review is made of studies which used surgical disruption of area postrema or the vagus nerve to investigate whether CTA and vomiting induced by motion may depend on common neural pathways or structures. When the chemoreceptive function of the area postrema (AP) is destroyed by complete ablation, rats develop CTA and cats and monkeys develop CTA and vomit. Thus the AP is not crucially involved in either CTA or vomiting induced by motion. However, after complete denervation of the stomach or after labyrinthectomy rats do not develop CTA when motion is used as the unconditioned stimulus. Studies of brainstem projections of the vagus nerve, the area postrema, the periaqueductal grey, and the vestibular system are used as the basis for speculation about regions which could mediate both motion-induced vomiting and behavioral food aversion.

  14. [Surgery for vertigo].

    PubMed

    Lacombe, H

    2009-04-01

    Spontaneous recovery or central compensation makes surgical procedures rare in patients with vertigo. Surgery for vertigo proposed after pharmacological or physical therapy fails to eliminate Ménière's disease and some very rare cases of paroxystic positional vertigo. The main target in treating Ménière's disease is to promote vestibular compensation, which is possible only with a nonprogressive and stable deficit leading to readjustment of vestibular reflexes. Surgical procedures can be classified as nondestructive (endolymphatic sac decompression, vestibular nerve decompression, patching of perilymphatic fistulas), selectively destructive (middle fossa or retrosigmoid vestibular neurotomy, lateral semi-circular plugging) and destructive (labyrinthectomy). Surgical indications essentially concern incapacitating vertigo and depend mainly on hearing status. In Ménière's disease, vestibular neurotomy can be regarded as the gold standard considering its good results on vertiginous episodes; however, scoring with functional and quality-of-life scales bring out residual deficiency in some cases.

  15. Meniere's disease in the elderly.

    PubMed

    Vibert, Dominique; Caversaccio, Marco; Häusler, Rudolf

    2010-10-01

    Menière disease usually begins in adults from 20 to 60 years old, and occurs in more than 10% of patients older than 65. The treatment of Menière disease in the elderly represents a challenge because of polymedication. Antivertiginous drugs such as betahistine and cinnarizin give good results with minor secondary effects. In contrast, major vestibular suppressor drugs such as thiethylperazin must be avoided as long-term treatment because of their side effects. Definitive vestibular surgical deafferentations such as labyrinthectomy and selective vestibular neurectomy represent optional procedures but must be carefully evaluated from case to case. Ablative procedures remain the efficient treatment of drop attacks, which represent a high potential risk of severe injuries by older patients sometimes with important social consequences.

  16. Trigeminal neuralgia secondary to basilar impression: A case report

    PubMed Central

    de Almeida Holanda, Maurus Marques; Pereira Neto, Normando Guedes; de Moura Peixoto, Gustavo; Pinheiro Santos, Rayan Haquim

    2015-01-01

    We report a rare case of trigeminal neuralgia. A 23-year-old woman with a history of 1 year of typical trigeminal neuralgia manifested the characteristics of basilar impression. Magnetic resonance imaging (MRI) demonstrated basilar impression, deformity of the posterior fossa with asymmetry of petrous bone, and compression of medulla oblongata in the topography of the odontoid apophysis. The operation was performed through a suboccipital craniectomy. The neuralgia disappeared after surgery and remains completely resolved until today. This is the second reported case of trigeminal neuralgia in a patient with basilar impression in Brazil. PMID:25972713

  17. Trigeminal neuralgia secondary to basilar impression: A case report.

    PubMed

    de Almeida Holanda, Maurus Marques; Pereira Neto, Normando Guedes; de Moura Peixoto, Gustavo; Pinheiro Santos, Rayan Haquim

    2015-01-01

    We report a rare case of trigeminal neuralgia. A 23-year-old woman with a history of 1 year of typical trigeminal neuralgia manifested the characteristics of basilar impression. Magnetic resonance imaging (MRI) demonstrated basilar impression, deformity of the posterior fossa with asymmetry of petrous bone, and compression of medulla oblongata in the topography of the odontoid apophysis. The operation was performed through a suboccipital craniectomy. The neuralgia disappeared after surgery and remains completely resolved until today. This is the second reported case of trigeminal neuralgia in a patient with basilar impression in Brazil.

  18. Surgically Clipping a Posterolaterally Projecting Posterior Communicating Artery Aneurysm With Anterior Petroclinoid Fold Fenestration.

    PubMed

    Ji, Shishun; Shi, Xiaodong; Chu, Xiaoshuai; Yuan, Xunhui; Sun, Gaoling; Bai, Yun'an; Liang, Aijun

    2017-01-01

    The anterior petroclinoid fold (APF) is a ligamentous structure consisting of collagen fiber and extends from the petrous apex to the anterior clinoid process. During the surgical clipping of some posterolaterally projecting posterior communicating artery aneurysms, it may pose a technical challenge due to obscuration of the aneurismal neck by the APF. Herein, the authors describe a simple and effective technique utilizing fenestration of the APF to facilitate visualization and surgical clipping of these aneurysms. To the best knowledge of us, this technique of the APF fenestration has been reported in only a few patients.

  19. Gorham-Stout syndrome affecting the temporal bone with cerebrospinal fluid leakage.

    PubMed

    Morimoto, Noriko; Ogiwara, Hideki; Miyazaki, Osamu; Kitamuara, Masayuki; Nishina, Sachiko; Nakazawa, Atsuko; Maekawa, Takanobu; Morota, Nobuhito

    2013-09-01

    Gorham-Stout syndrome is a rare disorder characterized by progressive osteolysis that leads to the disappearance of bone. Lymphvascular proliferation causes the local destruction of bony tissue. Owing to the low incidence of this syndrome, little is known about its etiology or treatment. We present an 11-year-old girl with Gorham-Stout syndrome that involved right petrous apex in temporal bone and upper clivus, which cause intracranial pressure increase and cerebrospinal fluid (CSF) leakage. The patient required surgical repair of CSF leakage by extradural middle fossa approach with temporal fascia flap. Combined treatment with interferon and propranolol prevented the progression of osteolysis.

  20. Gradenigo's syndrome--surgical management in a child.

    PubMed

    Humayun, Hassan Nabeel; Akhtar, Shabbir; Ahmed, Shakeel

    2011-04-01

    Otits media is a common problem. Some of its complications that were seen frequently in the preantibiotic era are rare today. We report a case of an 8 year boy who presented with earache, retro-orbital pain and diplopia secondary to a sixth nerve palsy--Gradenigo's syndrome. In this syndrome infection from the middle ear spreads medially to the petrous apex of the temporal bone. Work-up includes CT scan of the temporal bones. Timely management with intravenous antibiotics (+ surgery) is needed to prevent intra-cranial complications.

  1. Morphometric analysis of posterior fossa in Indian CP angle acoustic schwannoma patients

    PubMed Central

    Patibandla, Mohana Rao; Panigrahi, Manas K.; Gurram, Paniraj L.; Thotakura, Amit Kumar; Kulkarni, Dilip

    2016-01-01

    Aim: To study the morphometry of posterior fossa in Indian CP angle schwannoma patients in order to know its influence on the extent of excision of the CP angle acoustic schwannomas. Materials and Methods: One hundred cases of cerebellopontine angle schwannomas treated surgically by the senior author and 20 controls between January 2006 and June 2011 were consecutively investigated with computed tomography (CT) using the high-resolution CT bone windows before surgery. Evaluation of anatomic parameters of the petrous bone and posterior fossa cavity were done in all patients and controls. Data were entered in Excel software and were analyzed using NCSS software. All possible regression analysis was done to select the important variables to be included in the model to predict the excision of tumor with these variables. A prediction model was developed defining the binary outcome as total excision or subtotal excision as dependent variable and the morphometric data and grading of tumor as independent variables. Results: Interpetrous distance (IP) is the distance between the two petrous apices. Sigmoid distance (IS) distance is the distance between the two sigmoid points. Sigmoid point is the point at which the scalloped impression of the sigmoid sinus straightens to join the occipital bone posteriorly. SAG is the distance between the mid IP point and the mid-point on the inner wall of the occipital bone. The PM angle was 47.8±4.14 degrees (38-58), the PA angle was 42.68±4.47 degrees (34-53), the IP distance was 2.07±0.13 cm (1.5-2.8), the sagittal diameter of posterior fossa was 6.22±0.73 cm (5.1-9.8) and the intersigmoid distance was 9.45±0.73 cm (7.4-11). There was no significant gender difference in the posterior fossa morphometry between patients and controls. Inter-sigmoid distance and the petrous-apex angle were more in the Indians when compared to the European population mentioned in the Mathies and Samii study. Conclusions: The posterior fossa

  2. Postoperative CT findings in acoustic neurinomas operated upon by a translabyrinthine approach.

    PubMed

    Larsson, E M; Cronqvist, S; Sundbärg, G; Mercke, U; Harris, S

    1986-01-01

    The findings at CT examinations, performed on 46 patients with acoustic neurinomas about 6 months after translabyrinthine surgery, were analyzed and compared with preoperative findings. Direct as well as indirect signs of expansion had disappeared postoperatively. Bulging of cerebellar tissue towards the operative defect in the petrous bone, a finding not connected with local adhesions, was notable. Hypodensity in the vicinity of the removed tumor occurred either due to local widening of the subarachnoid space or due to changes within the cerebellar parenchyma. Local and general widening of the fourth ventricle as a sign of atrophy was a frequent finding.

  3. Transoral carotid ultrasonography using a micro convex probe with B-flow imaging for extracranial internal carotid artery dissection.

    PubMed

    Sakima, Hirokuni; Isa, Katsunori; Anegawa, Takahiro; Kokuba, Kazuhito; Nakachi, Koh; Goya, Yoshino; Tokashiki, Takashi; Ishiuchi, Shogo; Ohya, Yusuke

    2012-11-01

    We report on transoral carotid ultrasonography using a micro convex probe with B-flow imaging for determining spontaneous extracranial internal carotid artery dissection just below the petrous portion. A 49-year-old man suffered cortical and subcortical infarction in the region of the right middle cerebral artery. Magnetic resonance angiography on the third day of admission revealed spontaneous recanalization of the right internal carotid artery associated with an intimal flap-like structure at the petrous portion. Transoral carotid ultrasonography using a micro convex probe revealed right extracranial internal carotid artery dissection, showing an increased diameter of the right extracranial internal carotid artery with double lumen formation, stenosis of the true lumen, and a mobile intimal flap in B-flow imaging. Transoral carotid ultrasonography using a micro convex probe was helpful to attempt a self-expanding stent for recanalizing right extracranial internal carotid artery dissection. The patient recovered and was discharged ambulatory. The size of the micro convex probe was optimum for transoral carotid ultrasonography in our patient. Micro convex probe is more commonly used than the standard transoral carotid ultrasonography probe, which lacks versatility. We consider that transoral carotid ultrasonography using a micro convex probe could be routinely used for ultrasonographic evaluation of extracranial internal carotid artery dissection.

  4. Upper Nasopharyngeal Corridor for Transnasal Endoscopic Drainage of Petroclival Cholesterol Granulomas: Alternative Access in Conchal Sphenoid Patients

    PubMed Central

    Turan, Nefize; Baum, Griffin R.; Holland, Christopher M.; Ahmad, Faiz U.; Henriquez, Oswaldo A.; Pradilla, Gustavo

    2015-01-01

    Background Cholesterol granulomas arising at the petrous apex can be treated via traditional open surgical, endoscopic, and endoscopic-assisted approaches. Endoscopic approaches require access to the sphenoid sinus, which is technically challenging in patients with conchal sphenoidal anatomy. Clinical Presentation A 55-year-old woman presented with intermittent headaches and tinnitus. Formal audiometry demonstrated moderately severe bilateral hearing loss. CT of the temporal bones and sella revealed a well-demarcated expansile lytic mass. MRI of the face, orbit, and neck showed a right petrous apex mass measuring 22 × 18 × 19 mm that was hyperintense on T1- and T2-weighted images without enhancement, consistent with a cholesterol granuloma. The patient had a conchal sphenoidal anatomy. Operative Technique Herein, we present an illustrative case of a low-lying petroclival cholesterol granuloma in a patient with conchal sphenoidal anatomy to describe an alternative high nasopharyngeal corridor for endoscopic transnasal transclival access. Postoperative Course Postoperatively, the patient's symptoms recovered and no complications occurred. Follow-up imaging demonstrated a patent drainage tract without evidence of recurrence. Conclusion In patients with a conchal sphenoid sinus, endoscopic transnasal transclival access can be gained using a high nasopharyngeal approach. This corridor facilitates safe access to these lesions and others in this location. PMID:26929897

  5. A case of generalized lymphatic anomaly causing skull-base leakage and bacterial meningitis.

    PubMed

    Suga, Kenichi; Goji, Aya; Inoue, Miki; Kawahito, Masami; Taki, Masako; Mori, Kazuhiro

    2017-01-13

    Generalized lymphatic anomaly is a multifocal lymphatic malformation that affects the skin, thoracic viscera, and bones. A 3year-old Japanese boy presented with right facial palsy due to cystic tumors in the ipsilateral petrous bone. Pericardial effusion had been found incidentally and generalized lymphatic anomaly had been diagnosed by pericardial biopsy. Petrous bone tumor had been followed up without surgery. At the age of seven he presented with fever and disturbance of consciousness, and bacterial meningitis due to Streptococcus pneumoniae was diagnosed. Computed tomography and magnetic resonance imaging revealed middle skull-base leakage due to lymphatic malformation. He achieved complete recovery under intensive care with antibiotics and mechanical ventilation. One year later, he presented with multiple cystic formations in bilateral femora. At the 3-year follow-up, the patient was healthy with no recurrence of meningitis and osteolytic lesions in the femora were non-progressive. Computed tomography and magnetic resonance imaging are useful for demonstration of skull-base leakage by generalized lymphatic anomaly. We should consider generalized lymphatic anomaly among the differential diagnoses for skull-base leakage.

  6. Garcin syndrome resulting from a giant cell tumor of the skull base in a child.

    PubMed

    Bibas-Bonet, Hilda; Fauze, Ricardo A; Lavado, María Graciela; Páez, Rafael O; Nieman, Judith

    2003-05-01

    Garcin syndrome is characterized by a progressive ipsilateral involvement of cranial nerves, culminating in paralysis of all or at least seven of them, without sensory or motor long-tract disturbance, with no intracranial hypertension, and with osteoclastic involvement in the skull base on radiographic computed tomography. Giant cell tumor is a primary bone tumor rarely affecting the skull base. An 8-year-old female presented with a 3-month history of increasingly worsening right otalgia, tinnitus, hearing loss, right facial numbness, and diplopia. She was admitted with a 2-week history of swallowing difficulties, voice change, and right shoulder pain. Neurologic examination disclosed unilateral paralysis of the right fifth through twelfth cranial nerves, with no other abnormal neurologic findings. Skull radiographic computed tomography revealed lytic lesions in the right temporal petrous portion. Computed tomographic scan indicated a destructive mass involving the right greater wing of the sphenoid bone and temporal petrous apex. Magnetic resonance imaging demonstrated a tumor arising from the temporosphenoidal region, infiltrating neither the brain nor the brainstem. No hydrocephalus was observed. Biopsy revealed giant cell tumor. Posterior treatment consisted of radiotherapy. At an 8-year follow-up, the patient was well but with functional sequelae. There is no magnetic resonance imaging evidence of tumor growth. No other giant cell tumor presenting as Garcin syndrome is known to have been reported.

  7. Searching for the mother missed since the Second World War.

    PubMed

    Zupanič Pajnič, Irena; Petaros, Anja; Balažic, Jože; Geršak, Ksenija

    2016-11-01

    The aim of the study was to perform the genetic identification of a human cranium from a Second World War gravesite in Slovenia and find out if it belonged to the mother of a woman used as a family reference. Both genetic and anthropological examinations were carried out. The genetic examination was performed on 2 molars and petrous bone. Prior to DNA isolation 0.5 g of tooth and bone powder was decalcified. The DNA was purified in a Biorobot EZ1 (Qiagen) device. The nuclear DNA of the samples was quantified and short tandem repeat (STR) typing performed using two different autosomal and Y-STR kits. Up to 22.4 ng DNA/g of powder was obtained from samples analyzed. We managed to obtain nuclear DNA for successful STR typing from the left second molar and from the petrous bone. Full autosomal genetic profile including amelogenin locus revealed the male origin of the cranium that was further confirmed by the analyses of Y-STRs. The same conclusions were adopted after the anthropological analysis which identified the cranium as that of a very young Caucasoid male. The male origin of the cranium rejected the possibility of motherhood for the compared daughter. For traceability in the event of contamination, we created an elimination database including genetic profiles of the nuclear and Y-STRs of all persons that had been in contact with the analyzed cranium and no match was found.

  8. Fat graft-assisted internal auditory canal closure after retrosigmoid transmeatal resection of acoustic neuroma: Technique for prevention of cerebrospinal fluid leakage.

    PubMed

    Azad, Tareq; Mendelson, Zachary S; Wong, Anni; Jyung, Robert W; Liu, James K

    2016-02-01

    The retrosigmoid transmeatal approach remains an important strategy in the surgical management of acoustic neuromas. Gross total resection of acoustic neuromas requires removal of tumor within the cerebellopontine angle as well as tumor involving the internal auditory canal (IAC). Drilling into the petrous bone of the IAC can expose petrous air cells, which can potentially result in a fistulous tract to the nasopharynx manifesting as cerebrospinal fluid (CSF) rhinorrhea. We describe our method of IAC closure using autologous fat graft and assessed the rates of postoperative CSF leakage. We performed a retrospective study of 24 consecutive patients who underwent retrosigmoid transmeatal resection of acoustic neuroma who underwent our method of fat graft-assisted IAC closure. We assessed rates of postoperative CSF leak (incisional leak, rhinorrhea, or otorrhea), pseudomeningocele formation, and occurrence of meningitis. Twenty-four patients (10 males, 14 females) with a mean age of 47 years (range 18-84) underwent fat graft-assisted IAC closure. No lumbar drains were used postoperatively. There were no instances of postoperative CSF leak (incisional leak, rhinorrhea, or otorrhea), pseudomeningocele formation, or occurrence of meningitis. There were no graft site complications. Our results demonstrate that autologous fat grafts provide a safe and effective method of IAC defect closure to prevent postoperative CSF leakage after acoustic tumor removal via a retrosigmoid transmeatal approach. The surgical technique and operative nuances are described.

  9. [Computed tomography in the diagnosis of intracranial trigeminal neuroma].

    PubMed

    Xiao, J; Wang, D; Deng, K

    1993-12-01

    CT scans of 12 cases of intracranial trigeminal neuroma were presented. Three of the neuromas were located in petrous apex-middle cranial fossa, two in posterior cranial fossa, and 7 in both the middle and posterior cranial fossae. The tumors appeared hypo- and isodense on the plain CT scan. After contrast infusion, all tumors were well circumscribed with marked enhancement, which was homogeneous, inhomogeneous or circular. None of the trigeminal neuroma had surrounding brain edema. Of 12 cases, 10 showed change of cranial bones, which included dilatation of Meckle's cave and destructions of petrous apex, clivus and the bottom of middle cranial fossa. The tumor in one case extended to paranasopharyngeal space from the bottom of middle cranial fossa, Various features of trigeminal neuroma on CT were reviewed. Also presented were the author's experiences in differentiating intracranial trigeminal neuroma from meningiom, from pituitary adenoma spreading to parasella and glioma adjacent to cranial bottom in middle cranial fossa, and from acoustic neuroma, meningioma, cholesteatoma in cerebellopontine angle.

  10. Influence of the parameters of the Er:YAG laser on the apical sealing of apicectomized teeth.

    PubMed

    Marques, Aparecida Maria Cordeiro; Gerbi, Marleny Elizabeth M M; dos Santos, Jean Nunes; Noia, Manuela Pimentel; Oliveira, Priscila Chagas; Brugnera Junior, Aldo; Zanin, Fátima Antonia Aparecida; Pinheiro, Antonio Luiz Barbosa

    2011-07-01

    Failures in the sealing of the tooth apex have been considered to be responsible for most of the failures of apical surgeries. The Er:YAG laser has been proposed as an alternative for the use of rotator instruments in surgical endodontics due to its precision, lack of vibration, less post-operative discomfort, bacterial reduction, and less stress for patients and professionals. Following approval by the ethics committee, 12 extracted human canines without previous endodontic treatment with anatomically normal roots and free from apical lesions were washed in running tap water and disinfected. The teeth were sectioned axially at the crown-root junction and submitted to routine endodontic treatment. The apical limit was set at 1 mm before the apical foramen. The root canals were routinely filled with Gutta-Percha points and Sealer 26 and were randomly distributed into two groups (n = 6). In group I, apicectomy was performed with the Er:YAG laser (KAVO KEY Laser II®, Germany, λ = 2.940 nm, pulsed mode, 2051 tip, with air spray cooling, 250 mJ/15 Hz). Apical cut was performed of perpendicular mode 3 mm from the apical foramen. In group II, the same procedures and the same sequence as above was used, varying only the parameters of the Er:YAG laser (400 mJ/6 Hz). Sealing of the cervical end the apex was carried out with acrylic resin; the roots were covered by a layer of epoxy glue and two layers of nail polish. The specimens were divided into groups and fixed, by the cervical third, on wax. Impermeabilization of the residual root apical third was performed following the same procedures used in the cervical third but the residual apex was left free from the impermeabilization. After that, the roots were immersed in a 2% methylene blue solution and placed in a bacteriological oven for 48 h and then washed in running tap water for 2 h. The samples were sagittally split into two parts. The segments were visually observed and the one showing the greatest

  11. Adaptive Changes in Sensorimotor Coordination and Motion Sickness Following Repeated Exposures to Virtual Environments

    NASA Technical Reports Server (NTRS)

    Harm, D. L.; Taylor, L. C.; Bloomberg, J. J.

    2007-01-01

    Virtual environments offer unique training opportunities, particularly for training astronauts and preadapting them to the novel sensory conditions of microgravity. Two unresolved human factors issues in virtual reality (VR) systems are: 1) potential "cybersickness", and 2) maladaptive sensorimotor performance following exposure to VR systems. Interestingly, these aftereffects are often quite similar to adaptive sensorimotor responses observed in astronauts during and/or following space flight. Initial interpretation of novel sensory information may be inappropriate and result in perceptual errors. Active exploratory behavior in a new environment, with resulting feedback and the formation of new associations between sensory inputs and response outputs, promotes appropriate perception and motor control in the new environment. Thus, people adapt to consistent, sustained alterations of sensory input such as those produced by microgravity, unilateral labyrinthectomy and experimentally produced stimulus rearrangements. The purpose of this research was to compare disturbances in sensorimotor coordination produced by dome and head-mounted virtual environment displays and to examine the effects of exposure duration, and repeated exposures to VR systems. The first study examined disturbances in balance control, and the second study examined disturbances in eye-head-hand (EHH) and eye-head coordination.

  12. Consequences of postural changes and removal of vestibular inputs on the movement of air in and out of the lungs of conscious felines.

    PubMed

    Arshian, M; Holtje, R J; Cotter, L A; Rice, C D; Cass, S P; Yates, B J

    2007-07-01

    A variety of experimental approaches in human subjects and animal models established that the vestibular system contributes to regulation of respiration. In cats, the surgical elimination of labyrinthine signals produced changes in the spontaneous activity and posturally related responses of a number of respiratory muscles. However, these effects were complex and sometimes varied between muscle compartments, such that the physiological role of vestibulo-respiratory responses is unclear. The present study determined the functional significance of vestibulo-respiratory influences by examining the consequences of a bilateral labyrinthectomy on breathing rate and the pressure, volume, and flow rate of air exchanged during inspiration and expiration as body orientation with respect to gravity was altered. Data were collected from conscious adult cats acclimated to breathing through a facemask connected to a pneuomotach during 60 degrees head-up pitch and ear-down roll body rotations. Removal of vestibular inputs resulted in a 15% reduction in breathing rate, a 13% decrease in minute ventilation, a 16% decrease in maximal inspiratory airflow rate, and a 14% decrease in the maximal expiratory airflow rate measured when the animals were in the prone position. However, the lesions did not appreciably affect phasic changes in airflow parameters related to alterations in posture. These results suggest that the role of the vestibular system in the control of breathing is to modify baseline respiratory parameters in proportion to the general intensity of ongoing movements, and not to rapidly alter ventilation in accordance with body position.

  13. Non-Pharmacological Countermeasure to Decrease Landing Sickness and Improve Functional Performance

    NASA Technical Reports Server (NTRS)

    Rosenberg, M. J. F.; Kreutzberg, G. A.; Galvan-Garza, R. C.; Mulavara, A. P.; Reschke, M. F.

    2017-01-01

    Upon return from long-duration spaceflight, 100% of crewmembers experience motion sickness (MS) symptoms. The interactions between crewmembers' adaptation to a gravitational transition, the performance decrements resulting from MS and/or use of promethazine (PMZ), and the constraints imposed by mission task demands could significantly challenge and limit an astronaut's ability to perform functional tasks during gravitational transitions. Stochastic resonance (SR) is "noise benefit": adding noise to a system might increase the information (examples to the left and above). Stochastic vestibular stimulation (SVS), or low levels of noise applied to the vestibular system, improves balance and locomotor performance (Goel et al. 2015, Mulavara et al. 2011, 2015). In hemi-lesioned rat models, Samoudi et al. 2012 found that SVS increased GABA release on the lesioned, but not the intact side. Activation of the GABA pathway is important in modulating MS and promoting adaptability (Cohen 2008) and was seen to reverse MS symptoms in rats after unilateral labyrinthectomy (Magnusson et al. 2000). Thus, SVS could be used to promote GABA pathways to reduce MS and promote adaptability, eliminate the need for PMZ or other performance-inhibiting drugs.

  14. ACTH4 -10, Substance P, and Dizolcipine (Mk-801) Accelerate Functional Recovery After Hemilabyrinthectomy in Goldfish

    PubMed Central

    Mattioli, R.; Huston, J. P.; Spieler, R. E.

    2000-01-01

    In this study, we evaluated the goldfish model of hemilabyrinthectomy for investigating potential recovery-promoting drugs. In this lesion model, the unilateral removal of the labyrinth induces a postural imbalance in response to light (Dorsal Light Reflex), from which the animals can recover over time. The behavioral effects of two neuropeptides were tested–namely, of substance P and ACTH4-10, both of which are known to promote functional recovery in several other lesion models. Furthermore, the effect of MK- 801, an antagonist of the glutamatergic NMDAreceptor subtype, was tested because this substance has also been shown to exert a neuroprotective effect. After lesion of the right labyrinth, the animals (n=12) were treated intraperitoneally daily either with vehicle (n=12), substance P (n=11), ACTH4-10 (n=12), or MK- 801 (n=12). Another group (n=11), which served as a non-lesion control, did not receive hemilabyrinthectomy or systemic injections. The lesion group, treated post-operatively with vehicle, did not recover from the postural deviation over the 24-d testing period. In contrast, all three test substances accelerated the functional recovery after unilateral labyrinthectomy. The decrease of the dorsal light reflex persisted even after cessation of drug treatment after 20d. The results indicate that using the dorsal light reflex in the model of hemilabyrinthectomy in goldfish provides a useful approach to studying the ability of potential new neurotrophic or neuroprotective drugs to promote functional recovery. PMID:11486488

  15. Effects of lesions of the caudal cerebellar vermis on cardiovascular regulation in awake cats

    NASA Technical Reports Server (NTRS)

    Holmes, M. J.; Cotter, L. A.; Arendt, H. E.; Cass, S. P.; Yates, B. J.

    2002-01-01

    The vestibular system is known to participate in cardiovascular regulation during movement and postural alterations. The present study considered whether lesions of two regions of the posterior cerebellar vermis (the nodulus and uvula) that provide inputs to vestibular nucleus regions that affect control of blood pressure would alter cardiovascular responses during changes in posture. Blood pressure and heart rate were monitored in awake cats during nose-up tilts up to 60 degrees in amplitude before and following aspiration lesions of the nodulus or uvula; in most animals, cardiovascular responses were also recorded following the subsequent removal of vestibular inputs. Lesions of the nodulus or uvula did not affect baseline blood pressure or heart rate, although cardiovascular responses during nose-up tilts were altered. Increases in heart rate that typically occurred during 60 degrees nose-up tilt were attenuated in all three animals with lesions affecting both dorsal and ventral portions of the uvula; in contrast, the heart rate responses were augmented in the two animals with lesions mainly confined to the nodulus. Furthermore, following subsequent removal of vestibular inputs, uvulectomized animals, but not those with nodulus lesions, experienced more severe orthostatic hypotension than has previously been reported in cerebellum-intact animals with bilateral labyrinthectomies. These data suggest that the cerebellar nodulus and uvula modulate vestibulo-cardiovascular responses, although the two regions play different roles in cardiovascular regulation.

  16. Effect of Vestibulosympathetic Reflex and Baroreflex on Expression of pERK in the Nucleus Tractus Solitarius following Acute Hypotension in Conscious Rats.

    PubMed

    Jiang, Xian; Lan, Yan; Jin, Yuan-Zhe; Park, Joo Young; Park, Byung Geon; Ameer, Abdul Nasir; Park, Byung Rim

    2014-08-01

    Control of blood pressure is maintained by the interaction between the arterial baroreflex and vestibulosympathetic reflex during postural changes. In this study, the contributions of vestibular receptors and baroreceptors to the maintenance of blood pressure following acute hypotension were compared in terms of phosphorylated extracellular regulated protein kinase (pERK) expression in the nucleus tractus solitaries (NTS). Expression of pERK in the NTS was measured in conscious rats that had undergone bilateral labyrinthectomy (BL) and/or sinoaortic denervation (SAD) 5, 10, 20, and 40 min following acute hypotension induced by sodium nitroprusside (SNP) infusion. Expression of pERK increased significantly in the NTS in the control group following SNP infusion, and the expression peaked at 10 min after SNP infusion. The number of pERK positive neurons increased following SNP infusion in BL, SAD, and BL+SAD groups, although the increase was smaller than in control group. The BL group showed a relatively higher reduction in pERK expression than the SAD group, and the pERK expression in the NTS was localized to the caudal portion of the nuclei in the BL and SAD groups. These results suggest that the vestibular receptors may play a key role in maintaining blood pressure following acute hypotension; thus, the vestibular system may contribute to compensate for orthostatic hypotension.

  17. Ophthalmic artery aneurysm treated by surgical clipping and balloon-assisted temporary carotid occlusion.

    PubMed

    Dehdashti, Amir R

    2015-07-01

    A 29-year-old woman is diagnosed with a large broad-base right ophthalmic artery aneurysm. Despite an intact visual field, she complained of mild right visual blurriness. Between endovascular and surgical treatments, surgery was favored due to her young age. It was decided to perform the surgery with simultaneous endovascular temporary carotid balloon occlusion. A right pterional craniotomy and intradural anterior clinoidectomy were performed, the balloon was positioned in the petrous carotid, and the distal durai ring was opened exposing the proximal neck. Under temporary proximal carotid balloon occlusion and distal carotid clip occlusion, the aneurysm was fully dissected and clipped. Intraoperative angiogram confirmed complete aneurysm occlusion and patency of the ophthalmic artery. The patient's neurological exam remained unchanged. The video can be found here: http://youtu.be/BIQKTl9bDqA .

  18. Pipeline embolization device and subsequent vessel sacrifice for treatment of a bleeding carotid pseudoaneurysm at the skull base: a case report.

    PubMed

    Kadkhodayan, Yasha; Shetty, Vilaas S; Blackburn, Spiros L; Reynolds, Matthew R; Cross, DeWitte T; Moran, Christopher J

    2013-09-01

    An attempt at parent vessel reconstruction with Pipeline embolization devices to treat a mycotic pseudoaneurysm of the internal carotid artery at the skull base is presented. A 50-year-old woman with malignant otitis externa and bilateral temporal bone osteomyelitis presented with brisk bleeding from her left ear. She had bony dehiscence of the left carotid canal at CT and extravasation from a pseudoaneurysm of the carotid petrous segment at angiography. Carotid tortuosity proximally precluded placing a covered stent. After the lesion stopped bleeding spontaneously and given the presence of bilateral osteomyelitis putting the contralateral carotid at risk, the decision was made to attempt preservation of the parent vessel with flow diversion. However, bleeding recurred after 12 days, necessitating carotid sacrifice. This first reported experience in treating a carotid pseudoaneurysm at the skull base with the Pipeline device shows that transient cessation of bleeding is insufficient for flow diversion to be effective.

  19. Clinical computed tomography: Illustrated procedural guide

    SciTech Connect

    Chiu, L.C.; Lipcamon, J.D.; Yie-Chiu, B.S.

    1986-01-01

    This book presents an overview of physics and instrumentation. It addresses the role of the CT technologist; discusses the use of contrast media, its potential complications, and their avoidance, discusses techniques for scanning the brain, sella, orbits, petrous temporal bones, paranasal sinuses, neck, thorax, abdomen, pelvis, and spine; and demonstrates the normal anatomy of the foregoing regions. All this is followed by 171 examples of disease; a chapter on CT-guided biopsy and drainage procedures; and a description, in tabular form, of six different models of CT scanners, with the parameters for 15 separate examinations tabulated for each model of machine. The scanning techniques are presented in recipe fashion without clear reasons for the choices made or discussion on how choices can be varied for different clinical problems. They are also oriented toward one model of CT scanner. The anatomic sections are good but can be found in numerous other publications.

  20. Clinical Significance of an Unusual Variation

    PubMed Central

    Murugan, M. Senthil; Sudha, R.; Bhargavan, Rajesh

    2016-01-01

    The infrahyoid muscles are involved in vocalisation and swallowing; among these, the sternothyroid muscle is derived from the common primitive sheet. The improper differentiation of this muscle may therefore result in morphological variations. We report an unusual variation found during the dissection of a 65-year-old male cadaver at the Sri Manakula Vinayagar Medical College, Madagadipet, Pondicherry, India, in 2015. An anomalous belly of the right sternothyroid muscle was observed between the internal jugular (IJ) vein and the internal carotid artery with an additional insertion into the tympanic plate and petrous part of the temporal bone and the presence of a levator glandulae thyroideae muscle. The anomalous muscle may compress the IJ vein if it is related to the neurovascular structures of neck; hence, knowledge of variations of the infrahyoid muscles can aid in the evaluation of IJ vein compression among patients with idiopathic symptoms resulting from venous congestion. PMID:28003898

  1. Simple transposition technique for microvascular decompression using an expanded polytetrafluoroethylene "belt": technical note.

    PubMed

    Tanaka, Yuichiro; Uchida, Masashi; Onodera, Hidetaka; Hiramoto, Jun; Yoshida, Yasuyuki

    2014-06-17

    Microvascular decompression (MVD) is a standard surgical procedure for treating vascular compression syndromes. There are two basic ways to perform MVD: interposition using a prosthesis and transposition. With the transposition technique, adhesions and granuloma around the decompression site are avoided, but the required operation is more complex than that for the interposition method. We describe a simple, quick MVD transposition procedure that uses a small "belt" cut from a sheet of 0.3-mm-thick expanded polytetrafluoroethylene membrane. The belt has a hole at the wide end and the other end tapered to a point. The belt is encircled around offending vessels by inserting the pointed end into the hole. The pointed end is then passed through a dural tunnel over the posterior wall of the petrous bone and is tied two or three times. This method avoids the risks involved in handling a surgical needle close to the cranial nerves and vessels.

  2. MRI of paraganglioma of the filum terminale

    SciTech Connect

    Boncoeur-Martel, M.P.; Lesort, A.; Moreau, J.J.; Labrousse, F.; Roche, I.; Bouillet, P.; Pascaud, J.L.; Dupuy, J.P.

    1996-01-01

    Paragangliomas are benign tumors arising from paraganglionic cells of the sympathetic nervous system. They are of neuroectodermal derivation, with the majority occurring in the adrenal medulla. Extraadrenal locations are usually nonfunctioning and mostly observed (90%) in the head and neck region (carotid body or glomus jugulare tumors). Rare reported locations include the mediastinum, retroperitoneum, lungs, duodenum, and bladder. Within the CNS, paragangliomas have been observed in the pineal region, petrous ridge, sella turcica, and spinal canal. Paraganglioma of the cauda equina was first reported, but not recognized as such, in 1970. We know of 10 reports that describe MRI appearance. We present a new case and review the imaging findings of a paraganglioma of the filum terminale. 14 refs., 3 figs.

  3. Diversities in presentations of extrapulmonary tuberculosis

    PubMed Central

    Neelakantan, Shiba; Nair, Preeti P; Emmanuel, Roby V; Agrawal, Kavita

    2013-01-01

    The incidence of extrapulmonary tuberculosis (EPTB) has been increasing worldwide over the last few years. Tuberculous lymphadenitis is the most common form of the disease and is reported to occur in 25–60% of all EPTB cases. It is commonly seen in the cervical lymph nodes, but may also be in the larynx, pharynx, parotid and rarely, in the sinuses and petrous bone. The posterior triangle, supraclavicular and jugular nodes are most frequently affected. They are usually unilateral, although diffuse adenopathy may occur. TB involving cervical lymph nodes represents 50% of extrapulmonary TB. A series of six cases of tuberculous lymphadenitis with varying clinical features is documented here to alert one of its prevalence in developing countries. PMID:23449832

  4. Morphometry of the primate bony labyrinth: a new method based on high-resolution computed tomography.

    PubMed Central

    Spoor, F; Zonneveld, F

    1995-01-01

    A method is described for taking accurate measurements of the bony labyrinth of humans and other primates using high-resolution computed tomography (CT). The measurements comprise 8 dimensions, 14 orientations and 2 indices of the labyrinth, as well as 7 orientations of related structures of the petrous pyramid. Comparison of the measurements taken from CT scans with those taken from subsequently made casts and cryosections demonstrates that the method is sufficiently accurate to permit the morphometric analysis of labyrinthine size and shape. Since the CT method is nondestructive, fast and easy to perform, it is applicable to large samples and to rare or precious anthropological specimens. Images Fig. 1 Fig. 2 Fig. 4 PMID:7649826

  5. [Apical petrositis, osteomyelitis of the base of the skull bones and of the first cervical vertebra in a 5 year-old children following chicken pox].

    PubMed

    Bogomil'sky, M R; Polunin, M M; Zelikovich, E I; Soldatsky, Yu L; Burova, O V

    2016-01-01

    This publication was designed to describe a rare case of development of apicalpetrositis in a child presenting with acute otitis mediafollowing chicken pox experienced in the preceding period. We carried out the study with the use of computed tomography (CT) that demonstrated destruction of the temporal bone, bones of the base of the skull and of the first cervical vertebra. The treatment strategy chosen for the management of this condition that included antibiotic therapy and expectant observation proved justified and can be recommended as an algorithm of choice taking into consideration the difficulty of surgical approach to the apex of the petrous pyramid. However, this approach is associated with the high risk of disability arising from the potential injury to the craniocerebral nerves.

  6. Genome-wide patterns of selection in 230 ancient Eurasians.

    PubMed

    Mathieson, Iain; Lazaridis, Iosif; Rohland, Nadin; Mallick, Swapan; Patterson, Nick; Roodenberg, Songül Alpaslan; Harney, Eadaoin; Stewardson, Kristin; Fernandes, Daniel; Novak, Mario; Sirak, Kendra; Gamba, Cristina; Jones, Eppie R; Llamas, Bastien; Dryomov, Stanislav; Pickrell, Joseph; Arsuaga, Juan Luís; de Castro, José María Bermúdez; Carbonell, Eudald; Gerritsen, Fokke; Khokhlov, Aleksandr; Kuznetsov, Pavel; Lozano, Marina; Meller, Harald; Mochalov, Oleg; Moiseyev, Vyacheslav; Guerra, Manuel A Rojo; Roodenberg, Jacob; Vergès, Josep Maria; Krause, Johannes; Cooper, Alan; Alt, Kurt W; Brown, Dorcas; Anthony, David; Lalueza-Fox, Carles; Haak, Wolfgang; Pinhasi, Ron; Reich, David

    2015-12-24

    Ancient DNA makes it possible to observe natural selection directly by analysing samples from populations before, during and after adaptation events. Here we report a genome-wide scan for selection using ancient DNA, capitalizing on the largest ancient DNA data set yet assembled: 230 West Eurasians who lived between 6500 and 300 bc, including 163 with newly reported data. The new samples include, to our knowledge, the first genome-wide ancient DNA from Anatolian Neolithic farmers, whose genetic material we obtained by extracting from petrous bones, and who we show were members of the population that was the source of Europe's first farmers. We also report a transect of the steppe region in Samara between 5600 and 300 bc, which allows us to identify admixture into the steppe from at least two external sources. We detect selection at loci associated with diet, pigmentation and immunity, and two independent episodes of selection on height.

  7. Genome-wide patterns of selection in 230 ancient Eurasians

    PubMed Central

    Mathieson, Iain; Lazaridis, Iosif; Rohland, Nadin; Mallick, Swapan; Patterson, Nick; Roodenberg, Songül Alpaslan; Harney, Eadaoin; Stewardson, Kristin; Fernandes, Daniel; Novak, Mario; Sirak, Kendra; Gamba, Cristina; Jones, Eppie R.; Llamas, Bastien; Dryomov, Stanislav; Pickrel, Joseph; Arsuaga, Juan Luís; de Castro, José María Bermúdez; Carbonell, Eudald; Gerritsen, Fokke; Khokhlov, Aleksandr; Kuznetsov, Pavel; Lozano, Marina; Meller, Harald; Mochalov, Oleg; Moiseyev, Vayacheslav; Rojo Guerra, Manuel A.; Roodenberg, Jacob; Vergès, Josep Maria; Krause, Johannes; Cooper, Alan; Alt, Kurt W.; Brown, Dorcas; Anthony, David; Lalueza-Fox, Carles; Haak, Wolfgang; Pinhasi, Ron; Reich, David

    2016-01-01

    Ancient DNA makes it possible to directly witness natural selection by analyzing samples from populations before, during and after adaptation events. Here we report the first scan for selection using ancient DNA, capitalizing on the largest genome-wide dataset yet assembled: 230 West Eurasians dating to between 6500 and 1000 BCE, including 163 with newly reported data. The new samples include the first genome-wide data from the Anatolian Neolithic culture whose genetic material we extracted from the DNA-rich petrous bone and who we show were members of the population that was the source of Europe’s first farmers. We also report a complete transect of the steppe region in Samara between 5500 and 1200 BCE that allows us to recognize admixture from at least two external sources into steppe populations during this period. We detect selection at loci associated with diet, pigmentation and immunity, and two independent episodes of selection on height. PMID:26595274

  8. Malignant external otitis: CT evaluation

    SciTech Connect

    Curtin, H.D.; Wolfe, P.; May, M.

    1982-11-01

    Malignant external otitis is an aggressive infection caused by Pseudomonas aeruginosa that most often occurs in elderly diabetics. Malignant external otitis often spreads inferiorly from the external canal to involve the subtemporal area and progresses medially towards the petrous apex leading to multiple cranial nerve palsies. The computed tomographic (CT) findings in malignant external otitis include obliteration of the normal fat planes in the subtemporal area as well as patchy destruction of the bony cortex of the mastoid. The point of exit of the various cranial nerves can be identified on CT scans, and the extent of the inflammatory mass correlates well with the clinical findings. Four cases of malignant external otitis are presented. In each case CT provided a good demonstration of involvement of the soft tissues at the base of the skull.

  9. Hepatocellular carcinoma metastasizing to the skull base involving multiple cranial nerves.

    PubMed

    Kim, Soo Ryang; Kanda, Fumio; Kobessho, Hiroshi; Sugimoto, Koji; Matsuoka, Toshiyuki; Kudo, Masatoshi; Hayashi, Yoshitake

    2006-11-07

    We describe a rare case of HCV-related recurrent multiple hepatocellular carcinoma (HCC) metastasizing to the skull base involving multiple cranial nerves in a 50-year-old woman. The patient presented with symptoms of ptosis, fixation of the right eyeball, and left abducens palsy, indicating disturbances of the right oculomotor and trochlear nerves and bilateral abducens nerves. Brain contrast-enhanced computed tomography (CT) revealed an ill-defined mass with abnormal enhancement around the sella turcica. Brain magnetic resonance imaging (MRI) disclosed that the mass involved the clivus, cavernous sinus, and petrous apex. On contrast-enhanced MRI with gadolinium-chelated contrast medium, the mass showed inhomogeneous intermediate enhancement. The diagnosis of metastatic HCC to the skull base was made on the basis of neurological findings and imaging studies including CT and MRI, without histological examinations. Further studies may provide insights into various methods for diagnosing HCC metastasizing to the craniospinal area.

  10. Genome flux and stasis in a five millennium transect of European prehistory

    PubMed Central

    Gamba, Cristina; Jones, Eppie R.; Teasdale, Matthew D.; McLaughlin, Russell L.; Gonzalez-Fortes, Gloria; Mattiangeli, Valeria; Domboróczki, László; Kővári, Ivett; Pap, Ildikó; Anders, Alexandra; Whittle, Alasdair; Dani, János; Raczky, Pál; Higham, Thomas F. G.; Hofreiter, Michael; Bradley, Daniel G; Pinhasi, Ron

    2014-01-01

    The Great Hungarian Plain was a crossroads of cultural transformations that have shaped European prehistory. Here we analyse a 5,000-year transect of human genomes, sampled from petrous bones giving consistently excellent endogenous DNA yields, from 13 Hungarian Neolithic, Copper, Bronze and Iron Age burials including two to high (~22 × ) and seven to ~1 × coverage, to investigate the impact of these on Europe’s genetic landscape. These data suggest genomic shifts with the advent of the Neolithic, Bronze and Iron Ages, with interleaved periods of genome stability. The earliest Neolithic context genome shows a European hunter-gatherer genetic signature and a restricted ancestral population size, suggesting direct contact between cultures after the arrival of the first farmers into Europe. The latest, Iron Age, sample reveals an eastern genomic influence concordant with introduced Steppe burial rites. We observe transition towards lighter pigmentation and surprisingly, no Neolithic presence of lactase persistence. PMID:25334030

  11. Surgical removal of giant acoustic neurinomas involving the skull base. Report of two cases.

    PubMed

    Sawamura, Y; Nakagawa, Y; Ikota, T; Abe, H

    1989-10-01

    Neurinomas arising from the peripheral branch of the acoustic nerve distal to the internal auditory canal in the temporal bone are rare. Two advanced skull-base neurinomas are described which were situated mainly in the temporal petrous bone, and extended to the parapharyngeal space anteriorly, to the lateral cervical portion inferiorly, into the sphenoidal sinus medially, and into the middle and posterior cranial fossae compressing the brain stem. Both patients had been deaf for several years without other neurological deficits. The operative findings revealed that the fifth, seventh, and caudal cranial nerves were intact; therefore, it was suspected that these neurinomas originated primarily within the cochlea or the vestibule in the temporal bone. The tumors were completely removed via an extradural approach, with good results. Since the surgical treatment of such advanced skull-base neurinomas is difficult, the operative infratemporal fossa approach is described in detail.

  12. [Differential diagnosis of space demands in the cerebellopontine angle].

    PubMed

    Holst, B; Grunwald, I Q; Brill, G; Reith, W

    2004-11-01

    Most of the space demands in the cerebellopontine angle lie extra-axially. Important structures run within the cisterns of the cerebellopontine angle, such as the trigeminal, facial and vestibulocochlear nerves as well as the anterior inferior and posterior inferior cerebellar arteries and the veins which lead to the petrosal sinus. The most common space demands are caused by acoustic neuromas, meningeomas, vascular ectasia and aneurysms. Less common are epidermoid and other schwannomas as well as metastases, paragangliomas and arachnoidal cysts. Intra-axial tumours in the area of the cerebellopontine angle include the medulloblastoma, astrocytoma and the ependymoma, which occurs predominantly in children, in addition to the uncommon choroid plexus papilloma. Nearby, there are also space demands around the petrous bone, such as cholesterol granuloma, malignant otitis media, paraganglioma and metastases. For differential diagnosis, an understanding of the space requirements of the tumours in the cerebellopontine angle is needed in addition to knowledge of the anatomical structures.

  13. X-linked progressive mixed deafness: A new microdeletion that involves a more proximal region in Xq21

    SciTech Connect

    Piussan, C.; Mathieu, M.; Kolski, C.; Strunski, V.; Hanauer, A.; Dahl, N.; Biancalana, V.; Heyberger, S.

    1995-01-01

    We report a large two-generation pedigree with seven affected males segregating for an X-linked mixed conductive sensorineural deafness. The patients present with atypical Mondini-like dysplasia, dilated petrous facial canal, dilatation of the internal auditory meatus fully connected with enlarged cochlear canals, and, in one patient, a wide bulbous posterior labyrinth. Obligatory carrier females are mildly affected. Molecular characterization of this family revealed a deletion of locus DXS169, in Xq21.1. Loci DXS72 and DXS26, which, respectively, flank DXS169 proximally and distally, were intact. Since a gene responsible for X-linked progressive mixed deafness with perilymphatic gusher (DFN3) has previously been assigned by deletion mapping to a slightly more distal interval between DXS26 and DXS121, this study indicates either two different deafness genes or the involvement of a very large region in Xq21. 35 refs., 5 figs., 1 tab.

  14. Surgically Cured, Relapsed Pneumococcal Meningitis Due to Bone Defects, Non-invasively Identified by Three-dimensional Multi-detector Computed Tomography

    PubMed Central

    Akimoto, Takayoshi; Morita, Akihiko; Shiobara, Keiji; Hara, Makoto; Minami, Masayuki; Shijo, Katsunori; Nomura, Yasuyuki; Shigihara, Shuntaro; Haradome, Hiroki; Abe, Osamu; Kamei, Satoshi

    2016-01-01

    A 43-year-old Japanese man presented with a history of bacterial meningitis (BM). He was admitted to our department with a one-day history of headache and was diagnosed with relapse of BM based on the cerebrospinal fluid findings. The conventional imaging studies showed serial findings suggesting left otitis media, a temporal cephalocele, and meningitis. Three-dimensional multi-detector computed tomography (3D-MDCT) showed left petrous bone defects caused by the otitis media, and curative surgical treatment was performed. Skull bone structural abnormalities should be considered a cause of relapsed BM. 3D-MDCT was useful for revealing the causal minimal bone abnormality and performing pre-surgical mapping. PMID:27980270

  15. Peripheral facial palsy, the only presentation of a primitive neuroectodermal tumor of the skull base

    PubMed Central

    Kim, Hyung Jin; Kang, Ben; Joo, Eun Young; Kim, Eun Young; Kwon, Young Se

    2015-01-01

    Introduction Peripheral facial palsy is rarely caused by primary neoplasms, which are mostly constituted of tumors of the central nervous system, head and neck, and leukemia. Presentation of case A 2-month-old male infant presented with asymmetric facial expression for 3 weeks. Physical examination revealed suspicious findings of right peripheral facial palsy. Computed tomography of the temporal bone revealed a suspicious bone tumor centered in the right petrous bone involving surrounding bones with extension into the middle ear cavity and inner ear. Subtotal resection of the tumor was performed due to crucial structures adjacent the mass. Histopathology and immunohistochemistry of the resected tumor was consistent with primitive neuroectodermal tumor. Conclusion We report a rare case of a primitive neuroectodermal tumor located at the skull base presenting with only peripheral facial palsy. PMID:26710328

  16. Composition and distribution of elements and ultrastructural topography of a human cardiac calculus.

    PubMed

    Cheng, Ching-Li; Chang, Hsiao-Huang; Huang, Pei-Jung; Chu, Yu-Ting; Lin, Shan-Yang

    2013-04-01

    Trace elements (TEs) may contribute to the formation of calculi or stones or be involved in the aetiopathogenesis of stone diseases. The compositions and spatial distribution of elements from the inner nucleus to outer crust of the cardiac calculus were investigated by energy-dispersive X-ray fluorescence (EDXRF) spectrometer. The surface topograph, distribution map of elements, elemental and chemical compositions were also determined by environmental scanning electron microscope (ESEM)-energy-dispersive X-ray (EDX) analysis. Twenty-five elements were identifiable from 18 positions on the cardiac calculus by EDXRF spectrometer, in which the highest concentrations of toxic TEs (Ni, Pt, Hg, Sn, Pb, W, Au, Al, Si) and higher levels of essential TEs (Ca, Sr, Cr, P) were detected. A moderate positive Pearson's correlation between TEs concentrations of Mg, Ca or P and location differences from centre to periphery in the cardiac calculus was observed. A positive correlation was also found for Ca/Zn and Ca/Cu, indicating the gradual increase of calcium concentration from inner nucleus to outer crust of cardiac calculus. The drop-like nodules/crystals on the surface of petrous part of cardiac calculus were observed from ESEM analysis. ESEM-EDX analysis determined the calculus to be predominantly composed of calcium hydroxyapatite and cholesterol, as indicated by the petrous surface and drop-like nodules/crystals, respectively. This composition was confirmed using a portable Raman analyser. The spatial distribution analysis indicated a gradual increase in Mg, P and Ca concentrations from the inner nucleus to the outer crust of the cardiac calculus. The major chemical compositions of calcium hydroxyapatite and cholesterol were detected on this cardiac calculus.

  17. Anatomical landmarks for transnasal endoscopic skull base surgery.

    PubMed

    Sandu, Kishore; Monnier, Philippe; Pasche, Philippe

    2012-01-01

    Resection of midline skull base lesions involve approaches needing extensive neurovascular manipulation. Transnasal endoscopic approach (TEA) is minimally invasive and ideal for certain selected lesions of the anterior skull base. A thorough knowledge of endonasal endoscopic anatomy is essential to be well versed with its surgical applications and this is possible only by dedicated cadaveric dissections. The goal in this study was to understand endoscopic anatomy of the orbital apex, petrous apex and the pterygopalatine fossa. Six cadaveric heads (3 injected and 3 non injected) and 12 sides, were dissected using a TEA outlining systematically, the steps of surgical dissection and the landmarks encountered. Dissection done by the "2 nostril, 4 hands" technique, allows better transnasal instrumentation with two surgeons working in unison with each other. The main surgical landmarks for the orbital apex are the carotid artery protuberance in the lateral sphenoid wall, optic nerve canal, lateral optico-carotid recess, optic strut and the V2 nerve. Orbital apex includes structures passing through the superior and inferior orbital fissure and the optic nerve canal. Vidian nerve canal and the V2 are important landmarks for the petrous apex. Identification of the sphenopalatine artery, V2 and foramen rotundum are important during dissection of the pterygopalatine fossa. In conclusion, the major potential advantage of TEA to the skull base is that it provides a direct anatomical route to the lesion without traversing any major neurovascular structures, as against the open transcranial approaches which involve more neurovascular manipulation and brain retraction. Obviously, these approaches require close cooperation and collaboration between otorhinolaryngologists and neurosurgeons.

  18. Head and neck paragangliomas: clinical and molecular genetic classification

    PubMed Central

    Offergeld, Christian; Brase, Christoph; Yaremchuk, Svetlana; Mader, Irina; Rischke, Hans Christian; Gläsker, Sven; Schmid, Kurt W; Wiech, Thorsten; Preuss, Simon F; Suárez, Carlos; Kopeć, Tomasz; Patocs, Attila; Wohllk, Nelson; Malekpour, Mahdi; Boedeker, Carsten C; Neumann, Hartmut PH

    2012-01-01

    Head and neck paragangliomas are tumors arising from specialized neural crest cells. Prominent locations are the carotid body along with the vagal, jugular, and tympanic glomus. Head and neck paragangliomas are slowly growing tumors, with some carotid body tumors being reported to exist for many years as a painless lateral mass on the neck. Symptoms depend on the specific locations. In contrast to paraganglial tumors of the adrenals, abdomen and thorax, head and neck paragangliomas seldom release catecholamines and are hence rarely vasoactive. Petrous bone, jugular, and tympanic head and neck paragangliomas may cause hearing loss. The internationally accepted clinical classifications for carotid body tumors are based on the Shamblin Class I–III stages, which correspond to postoperative permanent side effects. For petrous-bone paragangliomas in the head and neck, the Fisch classification is used. Regarding the molecular genetics, head and neck paragangliomas have been associated with nine susceptibility genes: NF1, RET, VHL, SDHA, SDHB, SDHC, SDHD, SDHAF2 (SDH5), and TMEM127. Hereditary HNPs are mostly caused by mutations of the SDHD gene, but SDHB and SDHC mutations are not uncommon in such patients. Head and neck paragangliomas are rarely associated with mutations of VHL, RET, or NF1. The research on SDHA, SDHAF2 and TMEM127 is ongoing. Multiple head and neck paragangliomas are common in patients with SDHD mutations, while malignant head and neck paraganglioma is mostly seen in patients with SDHB mutations. The treatment of choice is surgical resection. Good postoperative results can be expected in carotid body tumors of Shamblin Class I and II, whereas operations on other carotid body tumors and other head and neck paragangliomas frequently result in deficits of the cranial nerves adjacent to the tumors. Slow growth and the tendency of hereditary head and neck paragangliomas to be multifocal may justify less aggressive treatment strategies. PMID:22584701

  19. Short latency vestibular evoked potentials in the chicken embryo

    NASA Technical Reports Server (NTRS)

    Jones, S. M.; Jones, T. A.

    1996-01-01

    Electrophysiological responses to pulsed linear acceleration stimuli were recorded in chicken embryos incubated for 19 or 20 days (E19/E20). Responses occurred within the first 16 ms following the stimulus onset. The evoked potentials disappeared following bilateral labyrinthectomy, but persisted following cochlear destruction alone, thus demonstrating that the responses were vestibular. Approximately 8 to 10 response peaks could be identified. The first 4 positive and corresponding negative components (early peaks with latencies < 6.0 ms) were scored and latencies and amplitudes quantified. Vestibular response latencies were significantly longer (P < 0.01) and amplitudes significantly smaller (P < 0.001) than those observed in 2-week-old birds. Mean response threshold for anesthetized embryos was -15.9dBre 1.0 g/ms, which was significantly higher (P < 0.03) than those observed in 2-week-old birds (-23.0dBre 1.0 g/ms). Latency/intensity functions (that is, slopes) were not significantly different between embryos and 2-week-old animals, but amplitude/intensity functions for embryos were significantly shallower than those for 2-week-old birds (P < 0.001). We presume that these differences reflect the refinement of sensory function that occurs following 19 to 20 days of incubation. The recording of vestibular evoked potentials provides an objective, direct and noninvasive measure of peripheral vestibular function in the embryo and, as such, the method shows promise as an investigative tool. The results of the present study form the definitive basis for using vestibular evoked potentials in the detailed study of avian vestibular ontogeny and factors that may influence it.

  20. Evaluation of the chemical model of vestibular lesions induced by arsanilate in rats

    SciTech Connect

    Vignaux, G.; Chabbert, C.; Gaboyard-Niay, S.; Travo, C.; Machado, M.L.; Denise, P.; Comoz, F.; Hitier, M.; Landemore, G.; Philoxène, B.; Besnard, S.

    2012-01-01

    Several animal models of vestibular deficits that mimic the human pathology phenotype have previously been developed to correlate the degree of vestibular injury to cognate vestibular deficits in a time-dependent manner. Sodium arsanilate is one of the most commonly used substances for chemical vestibular lesioning, but it is not well described in the literature. In the present study, we used histological and functional approaches to conduct a detailed exploration of the model of vestibular lesions induced by transtympanic injection of sodium arsanilate in rats. The arsanilate-induced damage was restricted to the vestibular sensory organs without affecting the external ear, the oropharynx, or Scarpa's ganglion. This finding strongly supports the absence of diffusion of arsanilate into the external ear or Eustachian tubes, or through the eighth cranial nerve sheath leading to the brainstem. One of the striking observations of the present study is the complete restructuring of the sensory epithelia into a non sensory epithelial monolayer observed at 3 months after arsanilate application. This atrophy resembles the monolayer epithelia observed postmortem in the vestibular epithelia of patients with a history of lesioned vestibular deficits such as labyrinthectomy, antibiotic treatment, vestibular neuritis, or Ménière's disease. In cases of Ménière's disease, aminoglycosides, and platinum-based chemotherapy, vestibular hair cells are destroyed, regardless of the physiopathological process, as reproduced with the arsanilate model of vestibular lesion. These observations, together with those presented in this study of arsanilate vestibular toxicity, suggest that this atrophy process relies on a common mechanism of degeneration of the sensory epithelia.

  1. Role of the flocculus in mediating vestibular nucleus neuron plasticity during vestibular compensation in the rat

    PubMed Central

    Johnston, Alex R; Seckl, Jonathan R; Dutia, Mayank B

    2002-01-01

    We investigated the role of the cerebellar flocculus in mediating the adaptive changes that occur in the intrinsic properties of brainstem medial vestibular nucleus (MVN) neurons during vestibular compensation. Ipsi-lesional, but not contra-lesional, flocculectomy prevented the compensatory increase in intrinsic excitability (CIE) that normally occurs in the de-afferented MVN neurons within 4 h after unilateral labyrinthectomy (UL). Flocculectomy did not, however, prevent the down-regulation of efficacy of GABA receptors that also occurs in these neurons after UL, indicating that these responses of the MVN neurons to deafferentation are discrete, parallel processes. CIE was also abolished by intra-floccular microinjection of the metabotropic glutamate receptor (mGluR) antagonist AIDA, and the protein kinase C inhibitor bisindolymaleimide I (BIS-I). The serene-threonine kinase inhibitor H-7 had no effect when microinjected at the time of de-afferentation, but abolished CIE if microinjected 2 h later. These cellular effects are in line with the recently reported retardatory effects of BIS-I and H-7 on behavioural recovery after UL. They demonstrate that the increase in intrinsic excitability in MVN neurons during vestibular compensation is cerebellum dependent, and requires mGluR activation and protein phosphorylation in cerebellar cortex. Furthermore, microinjection of the glucocorticoid receptor (GR) antagonist RU38486 into the ipsi-lesional flocculus also abolished CIE in MVN neurons. Thus an important site for glucocorticoids in facilitating vestibular compensation is within the cerebellar cortex. These observations ascribe functional significance to the high levels of GR and 11-β-HSD Type 1 expression in cerebellum. PMID:12482895

  2. Neurogenic Potential of the Vestibular Nuclei and Behavioural Recovery Time Course in the Adult Cat Are Governed by the Nature of the Vestibular Damage

    PubMed Central

    Dutheil, Sophie; Lacour, Michel; Tighilet, Brahim

    2011-01-01

    Functional and reactive neurogenesis and astrogenesis are observed in deafferented vestibular nuclei after unilateral vestibular nerve section in adult cats. The newborn cells survive up to one month and contribute actively to the successful recovery of posturo-locomotor functions. This study investigates whether the nature of vestibular deafferentation has an incidence on the neurogenic potential of the vestibular nuclei, and on the time course of behavioural recovery. Three animal models that mimic different vestibular pathologies were used: unilateral and permanent suppression of vestibular input by unilateral vestibular neurectomy (UVN), or by unilateral labyrinthectomy (UL, the mechanical destruction of peripheral vestibular receptors), or unilateral and reversible blockade of vestibular nerve input using tetrodotoxin (TTX). Neurogenesis and astrogenesis were revealed in the vestibular nuclei using bromodeoxyuridine (BrdU) as a newborn cell marker, while glial fibrillary acidic protein (GFAP) and glutamate decarboxylase 67 (GAD67) were used to identify astrocytes and GABAergic neurons, respectively. Spontaneous nystagmus and posturo-locomotor tests (static and dynamic balance performance) were carried out to quantify the behavioural recovery process. Results showed that the nature of vestibular loss determined the cellular plastic events occurring in the vestibular nuclei and affected the time course of behavioural recovery. Interestingly, the deafferented vestibular nuclei express neurogenic potential after acute and total vestibular loss only (UVN), while non-structural plastic processes are involved when the vestibular deafferentation is less drastic (UL, TTX). This is the first experimental evidence that the vestibular complex in the brainstem can become neurogenic under specific injury. These new data are of interest for understanding the factors favouring the expression of functional neurogenesis in adult mammals in a brain repair perspective, and are of

  3. Morphologically mixed chemical-electrical synapses formed by primary afferents in rodent vestibular nuclei as revealed by immunofluorescence detection of connexin36 and vesicular glutamate transporter-1

    PubMed Central

    Nagy, James I.; Bautista, Wendy; Blakley, Brian; Rash, John E.

    2013-01-01

    Axon terminals forming mixed chemical/electrical synapses in the lateral vestibular nucleus of rat were described over forty years ago. Because gap junctions formed by connexins are the morphological correlate of electrical synapses, and with demonstrations of widespread expression of the gap junction protein connexin36 (Cx36) in neurons, we investigated the distribution and cellular localization of electrical synapses in the adult and developing rodent vestibular nuclear complex, using immunofluorescence detection of Cx36 as a marker for these synapses. In addition, we examined Cx36 localization in relation to that of the nerve terminal marker vesicular glutamate transporter-1 (vglut-1). An abundance of immunolabelling for Cx36 in the form of Cx36-puncta was found in each of the four major vestibular nuclei of adult rat and mouse. Immunolabelling was associated with somata and initial dendrites of medium and large neurons, and was absent in vestibular nuclei of Cx36 knockout mice. Cx36-puncta were seen either dispersed or aggregated into clusters on the surface of neurons, and were never found to occur intracellularly. Nearly all Cx36-puncta were localized to large nerve terminals immunolabelled for vglut-1. These terminals and their associated Cx36-puncta were substantially depleted after labyrinthectomy. Developmentally, labelling for Cx36 was already present in the vestibular nuclei at postnatal day 5, where it was only partially co-localized with vglut-1, and did not become fully associated with vglut-1-positive terminals until postnatal day 20 to 25. The results show that vglut-1-positive primary afferent nerve terminals form mixed synapses throughout the vestibular nuclear complex, that the gap junction component of these synapses contain Cx36, that multiple Cx36-containing gap junctions are associated with individual vglut-1 terminals and that the development of these mixed synapses is protracted over several postnatal weeks. PMID:23912039

  4. Morphologically mixed chemical-electrical synapses formed by primary afferents in rodent vestibular nuclei as revealed by immunofluorescence detection of connexin36 and vesicular glutamate transporter-1.

    PubMed

    Nagy, J I; Bautista, W; Blakley, B; Rash, J E

    2013-11-12

    Axon terminals forming mixed chemical/electrical synapses in the lateral vestibular nucleus of rat were described over 40 years ago. Because gap junctions formed by connexins are the morphological correlate of electrical synapses, and with demonstrations of widespread expression of the gap junction protein connexin36 (Cx36) in neurons, we investigated the distribution and cellular localization of electrical synapses in the adult and developing rodent vestibular nuclear complex, using immunofluorescence detection of Cx36 as a marker for these synapses. In addition, we examined Cx36 localization in relation to that of the nerve terminal marker vesicular glutamate transporter-1 (vglut-1). An abundance of immunolabeling for Cx36 in the form of Cx36-puncta was found in each of the four major vestibular nuclei of adult rat and mouse. Immunolabeling was associated with somata and initial dendrites of medium and large neurons, and was absent in vestibular nuclei of Cx36 knockout mice. Cx36-puncta were seen either dispersed or aggregated into clusters on the surface of neurons, and were never found to occur intracellularly. Nearly all Cx36-puncta were localized to large nerve terminals immunolabeled for vglut-1. These terminals and their associated Cx36-puncta were substantially depleted after labyrinthectomy. Developmentally, labeling for Cx36 was already present in the vestibular nuclei at postnatal day 5, where it was only partially co-localized with vglut-1, and did not become fully associated with vglut-1-positive terminals until postnatal day 20-25. The results show that vglut-1-positive primary afferent nerve terminals form mixed synapses throughout the vestibular nuclear complex, that the gap junction component of these synapses contains Cx36, that multiple Cx36-containing gap junctions are associated with individual vglut-1 terminals and that the development of these mixed synapses is protracted over several postnatal weeks.

  5. Vestibular lesion-induced developmental plasticity in spinal locomotor networks during Xenopus laevis metamorphosis.

    PubMed

    Beyeler, Anna; Rao, Guillaume; Ladepeche, Laurent; Jacques, André; Simmers, John; Le Ray, Didier

    2013-01-01

    During frog metamorphosis, the vestibular sensory system remains unchanged, while spinal motor networks undergo a massive restructuring associated with the transition from the larval to adult biomechanical system. We investigated in Xenopus laevis the impact of a pre- (tadpole stage) or post-metamorphosis (juvenile stage) unilateral labyrinthectomy (UL) on young adult swimming performance and underlying spinal locomotor circuitry. The acute disruptive effects on locomotion were similar in both tadpoles and juvenile frogs. However, animals that had metamorphosed with a preceding UL expressed restored swimming behavior at the juvenile stage, whereas animals lesioned after metamorphosis never recovered. Whilst kinematic and electrophysiological analyses of the propulsive system showed no significant differences in either juvenile group, a 3D biomechanical simulation suggested that an asymmetry in the dynamic control of posture during swimming could account for the behavioral restoration observed in animals that had been labyrinthectomized before metamorphosis. This hypothesis was subsequently supported by in vivo electromyography during free swimming and in vitro recordings from isolated brainstem/spinal cord preparations. Specifically, animals lesioned prior to metamorphosis at the larval stage exhibited an asymmetrical propulsion/posture coupling as a post-metamorphic young adult. This developmental alteration was accompanied by an ipsilesional decrease in propriospinal coordination that is normally established in strict left-right symmetry during metamorphosis in order to synchronize dorsal trunk muscle contractions with bilateral hindlimb extensions in the swimming adult. Our data thus suggest that a disequilibrium in descending vestibulospinal information during Xenopus metamorphosis leads to an altered assembly of adult spinal locomotor circuitry. This in turn enables an adaptive compensation for the dynamic postural asymmetry induced by the vestibular imbalance

  6. The Magnus-Rademaker Scientific Film Collection: Ethical Issues on Animal Experimentation (1908-1940).

    PubMed

    Koehler, Peter J; Lameris, Bregt

    2016-01-01

    The Magnus-Rademaker scientific film collection (1908-1940) deals with the physiology of body posture by the equilibrium of reflex musculature contractions for which experimental studies were carried out with animals (e.g., labyrinthectomies, cerebellectomies, and brain stem sections) as well as observations done on patients. The films were made for demonstrations at congresses as well as educational objectives and film stills were published in their books. The purpose of the present study is to position these films and their makers within the contemporary discourse on ethical issues and animal rights in the Netherlands and the earlier international debates. Following an introduction on animal rights and antivivisection movements, we describe what Magnus and Rademaker thought about these issues. Their publications did not provide much information in this respect, probably reflecting their adherence to implicit ethical codes that did not need explicit mentioning in publications. Newspaper articles, however, revealed interesting information. Unnecessary suffering of an animal never found mercy in Magnus' opinion. The use of cinematography was expanded to the reduction of animal experimentation in student education, at least in the case of Rademaker, who in the 1930s was involved in a governmental committee for the regulation of vivisection and cooperated with the antivivisection movement. This resulted not only in a propaganda film for the movement but also in films that demonstrate physiological experiments for students with the purpose to avert repetition and to improve the teaching of experiments. We were able to identify the pertinent films in the Magnus-Rademaker film collection. The production of vivisection films with this purpose appears to have been common, as is shown in news messages in European medical journals of the period.

  7. Neurocinematography in Pre-World War II Netherlands: The Magnus-Rademaker Collection.

    PubMed

    Koehler, Peter J; Lameris, Bregt; Hielscher, Eva

    2016-01-01

    Historical films made by neuroscientists have shown up in several countries during past years. Although originally supposed to have been lost, we recently found a collection of films produced between 1909 and 1940 by Rudolf Magnus (1873-1927), professor of pharmacology (Utrecht) and his student Gysbertus Rademaker (1887-1957), professor of physiology (1928, succeeding Willem Einthoven) and neurology (1945, both in Leiden). Both collections deal with the physiology of body posture by the equilibrium of reflex musculature contractions for which experimental studies were done with animals (labyrinthectomies, cerebellectomies, and brainstem sections) and observations on patients. The films demonstrate the results of these studies. Moreover, there are films with babies showing tonic neck reflexes and moving images capturing adults with cerebellar symptoms following cerebellectomies for tumors and several other conditions. Magnus' studies resulted in his well-known Körperstellung (1924, "Body Posture") and Rademaker's research in his Das Stehen (1931, "Standing"). The films probably had an educative and scientific purpose. Magnus demonstrated his films at congresses, including the Eighth International Congress of Physiologists (Vienna, 1910) and Rademaker screened his moving images at meetings of the Amsterdam Neurologists Society (at several occasions as reflected in the Winkler-Monakow correspondence and the Nederlands Tijdschrift voor Geneeskunde). Next to these purposes, the films were used to analyze movement and a series of images from the films were published in articles and books. The films are important historical sources that provide a portrait of the pre-World War II era in neuroscience, partly answering questions on how physicians dealt with patients and researchers with their laboratory animals. Moreover, the films confirm that cinematography was an important scientific tool in neuroscience research.

  8. Short latency compound action potentials from mammalian gravity receptor organs

    NASA Technical Reports Server (NTRS)

    Jones, T. A.; Jones, S. M.

    1999-01-01

    Gravity receptor function was characterized in four mammalian species using far-field vestibular evoked potentials (VsEPs). VsEPs are compound action potentials of the vestibular nerve and central relays that are elicited by linear acceleration ramps applied to the cranium. Rats, mice, guinea pigs, and gerbils were studied. In all species, response onset occurred within 1.5 ms of the stimulus onset. Responses persisted during intense (116 dBSPL) wide-band (50 to 50 inverted question mark omitted inverted question mark000 Hz) forward masking, whereas auditory responses to intense clicks (112 dBpeSPL) were eliminated under the same conditions. VsEPs remained after cochlear extirpation but were eliminated following bilateral labyrinthectomy. Responses included a series of positive and negative peaks that occurred within 8 ms of stimulus onset (range of means at +6 dBre: 1.0 g/ms: P1=908 to 1062 micros, N1=1342 to 1475 micros, P2=1632 to 1952 micros, N2=2038 to 2387 micros). Mean response amplitudes at +6 dBre: 1.0 g/ms ranged from 0.14 to 0.99 microV. VsEP input/output functions revealed latency slopes that varied across peaks and species ranging from -19 to -51 micros/dB. Amplitude-intensity slopes also varied ranging from 0.04 to 0.08 microV/dB for rats and mice. Latency values were comparable to those of birds although amplitudes were substantially smaller in mammals. VsEP threshold values were considerably higher in mammals compared to birds and ranged from -8.1 to -10.5 dBre 1.0 g/ms across species. These results support the hypothesis that mammalian gravity receptors are less sensitive to dynamic stimuli than are those of birds.

  9. Chronic exposure to hypergravity affects thyrotropin-releasing hormone levels in rat brainstem and cerebellum

    NASA Technical Reports Server (NTRS)

    Daunton, N. G.; Tang, F.; Corcoran, M. L.; Fox, R. A.; Man, S. Y.

    1998-01-01

    In studies to determine the neurochemical mechanisms underlying adaptation to altered gravity we have investigated changes in neuropeptide levels in brainstem, cerebellum, hypothalamus, striatum, hippocampus, and cerebral cortex by radioimmunoassay. Fourteen days of hypergravity (hyperG) exposure resulted in significant increases in thyrotropin-releasing hormone (TRH) content of brainstem and cerebellum, but no changes in levels of other neuropeptides (beta-endorphin, cholecystokinin, met-enkephalin, somatostatin, and substance P) examined in these areas were found, nor were TRH levels significantly changed in any other brain regions investigated. The increase in TRH in brainstem and cerebellum was not seen in animals exposed only to the rotational component of centrifugation, suggesting that this increase was elicited by the alteration in the gravitational environment. The only other neuropeptide affected by chronic hyperG exposure was met-enkephalin, which was significantly decreased in the cerebral cortex. However, this alteration in met-enkephalin was found in both hyperG and rotation control animals and thus may be due to the rotational rather than the hyperG component of centrifugation. Thus it does not appear as if there is a generalized neuropeptide response to chronic hyperG following 2 weeks of exposure. Rather, there is an increase only of TRH and that occurs only in areas of the brain known to be heavily involved with vestibular inputs and motor control (both voluntary and autonomic). These results suggest that TRH may play a role in adaptation to altered gravity as it does in adaptation to altered vestibular input following labyrinthectomy, and in cerebellar and vestibular control of locomotion, as seen in studies of ataxia.

  10. Vestibular short latency responses to pulsed linear acceleration in unanesthetized animals

    NASA Technical Reports Server (NTRS)

    Jones, T. A.

    1992-01-01

    Linear acceleration transients were used to elicit vestibular compound action potentials in non-invasively prepared, unanesthetized animals for the first time (chicks, Gallus domesticus, n = 33). Responses were composed of a series of up to 8 dominant peaks occurring within 8 msec of the stimulus. Response amplitudes for 1.0 g stimulus ranged from 1 to 10 microV. A late, slow, triphasic, anesthesia-labile component was identified as a dominant response feature in unanesthetized animals. Amplitudes increased and latencies decreased as stimulus intensity was increased (MANOVA P less than 0.05). Linear regression slope ranges were: amplitudes = 1.0-5.0 microV/g; latencies = -300 to -1100 microseconds/g. Thresholds for single polarity stimuli (0.035 +/- 0.022 g, n = 11) were significantly lower than those of alternating polarity (0.074 +/- 0.028 g, n = 18, P less than 0.001). Bilateral labyrinthectomy eliminated responses whereas bilateral extirpation of cochleae did not significantly change response thresholds. Intense acoustic masking (100/104 dB SL) produced no effect in 2 animals, but did produce small to moderate effects on response amplitudes in 7 others. Changes were attributed to effects on vestibular end organs. Results of unilateral labyrinth blockade (tetrodotoxin) suggest that P1 and N1 preferentially reflect ipsilateral eighth nerve compound action potentials whereas components beyond approximately 2 msec reflect activity from vestibular neurons that depend on both labyrinths. The results demonstrate that short latency vestibular compound action potentials can be measured in unanesthetized, non-invasively prepared animals.

  11. Correlation of Fos expression and circling asymmetry during gerbil vestibular compensation

    NASA Technical Reports Server (NTRS)

    Kaufman, G. D.; Shinder, M. E.; Perachio, A. A.

    1999-01-01

    Vestibular compensation is a central nervous system process resulting in recovery of functional movement and control following a unilateral vestibular lesion. Small pressure injections of phosphorothioate 20mer oligonucleotides were used to probe the role of the Fos transcription protein during vestibular compensation in the gerbil brainstem. During isoflurane gas anesthesia, antisense probes against the c-fos mRNA sequence were injected into the medial vestibular and prepositus nuclei unilaterally prior to a unilateral surgical labyrinthectomy. Anionic dyes, which did not interact with the oligonucleotides, were used to mark the injection site and help determine the extent of diffusion. The antiFos oligonucleotide injections reduced Fos expression at the injection site in neurons which normally express Fos after the lesion, and also affected circling behavior induced by hemilabyrinthectomy. With both ipsilateral and contralateral medial vestibular and prepositus nuclei injections, less ipsilateral and more contralateral circling was noted in animals injected with antiFos injections as compared to non-injected controls. The degree of change in these behaviors was dependent upon the side of the injection. Histologically, antiFos injections reduced the number of Fos immunolabeled neurons around the injection site, and increased Fos expression contralaterally. The correlation of the number of neurons with Fos expression to turning behavior was stronger for contralateral versus ipsilateral turns, and for neurons in the caudal and ipsilateral sub-regions of the medial vestibular and prepositus nuclei. The results are discussed in terms of neuronal firing activity versus translational activity based on the asymmetrical expression of the Fos inducible transcription factor in the medial vestibular and prepositus nuclei. Although ubiquitous in the brain, transcription factors like Fos can serve localized and specific roles in sensory-specific adaptive stimuli. Antisense

  12. Gruber, Gradenigo, Dorello, and Vail: key personalities in the historical evolution and modern-day understanding of Dorello's canal.

    PubMed

    Reddy, Renuka K; Reddy, Rohit K; Jyung, Robert W; Eloy, Jean Anderson; Liu, James K

    2016-01-01

    A century ago an ambitious young anatomist in Rome, Primo Dorello, who sought to understand the cause of abducent nerve palsy that often occurred in patients with severe middle ear infections, conducted intricate studies on the intracranial course of the nerve. In his findings, he identified that the abducent nerve passes through a narrow sinus near the apex of the petrous bone, which formed an osteofibrous canal. Dorello suggested that in this enclosed region the abducent nerve may be particularly vulnerable to compression due to the vascular edema accompanying the infection. Although his work was widely appreciated, it was not well received by all. Interestingly, Giuseppe Gradenigo, one of the most prominent Italian otologists of the early 20th century, who was known for his work on a triad of symptoms (Gradenigo's syndrome) that accompanies petrous apicitis, a result of severe middle ear infections, was obstinate in his criticism of Dorello's findings. Thus a scientific duel began, with a series of correspondence between these two academics-one who was relatively new to the otological community (Dorello) and one who was well reputed in that community (Gradenigo). The disagreement ultimately ebbed in 1909, when Dorello published a report in response to Gradenigo's criticisms and convinced Gradenigo to change his views. Today Dorello's canal is widely recognized as a key landmark in skull base surgery of the petroclival region and holds clinical significance due to its relation to the abducent nerve and surrounding vascular structures. Yet, although academics such as Dorello and Gradenigo are recognized for their work on the canal, it is important not to forget the others throughout history who have contributed to the modern-day understanding of this anatomical structure. In fact, although the level of anatomical detail found in Dorello's work was previously unmatched, the first description of the canal was made by the experienced Austrian anatomist Wenzel Leopold

  13. Dual-Port 2D and 3D Endoscopy: Expanding the Limits of the Endonasal Approaches to Midline Skull Base Lesions with Lateral Extension

    PubMed Central

    Beer-Furlan, Andre; Evins, Alexander I.; Rigante, Luigi; Anichini, Giulio; Stieg, Philip E.; Bernardo, Antonio

    2014-01-01

    Objective To investigate a novel dual-port endonasal and subtemporal endoscopic approach targeting midline lesions with lateral extension beyond the intracavernous carotid artery anteriorly and the Dorello canal posteriorly. Methods Ten dual-port approaches were performed on five cadaveric heads. All specimens underwent an endoscopic endonasal approach from the sella to middle clivus. The endonasal port was combined with an anterior or posterior endoscopic extradural subtemporal approach. The anterior subtemporal port was placed directly above the middle third of the zygomatic arch, and the posterior port was placed at its posterior root. The extradural space was explored using two-dimensional and three-dimensional endoscopes. Results The anterior subtemporal port complemented the endonasal port with direct access to the Meckel cave, lateral sphenoid sinus, superior orbital fissure, and lateral and posterosuperior compartments of the cavernous sinus; the posterior subtemporal port enhanced access to the petrous apex. Endoscopic dissection and instrument maneuverability were feasible and performed without difficulty in both the anterior and posterior subtemporal ports. Conclusion The anterior and posterior subtemporal ports enhanced exposure and control of the region lateral to the carotid artery and Dorello canal. Dual-port neuroendoscopy is still minimally invasive yet dramatically increases surgical maneuverability while enhancing visualization and control of anatomical structures. PMID:25072012

  14. Percutaneous inner-ear access via an image-guided industrial robot system

    PubMed Central

    Baron, S; Eilers, H; Munske, B; Toennies, JL; Balachandran, R; Labadie, RF; Ortmaier, T; Webster, RJ

    2014-01-01

    Image-guided robots have been widely used for bone shaping and percutaneous access to interventional sites. However, due to high-accuracy requirements and proximity to sensitive nerves and brain tissues, the adoption of robots in inner-ear surgery has been slower. In this paper the authors present their recent work towards developing two image-guided industrial robot systems for accessing challenging inner-ear targets. Features of the systems include optical tracking of the robot base and tool relative to the patient and Kalman filter-based data fusion of redundant sensory information (from encoders and optical tracking systems) for enhanced patient safety. The approach enables control of differential robot positions rather than absolute positions, permitting simplified calibration procedures and reducing the reliance of the system on robot calibration in order to ensure overall accuracy. Lastly, the authors present the results of two phantom validation experiments simulating the use of image-guided robots in inner-ear surgeries such as cochlear implantation and petrous apex access. PMID:20718268

  15. IERAPSI project: simulation of a canal wall-up mastoidectomy.

    PubMed

    Neri, E; Sellari Franceschini, S; Berrettini, S; Caramella, D; Bartolozzi, C

    2006-03-01

    Among the various EU research projects concerning the medical application of virtual reality, the project Ist-1999-12175, called IERAPSI (Integrated Environment for the Rehearsal and Planning of Surgical Interventions), specifically addressed the creation of a virtual and interactive surgical field for the temporal bone using three-dimensional images derived from CT data. We report on the experience obtained in the IERAPSI project in simulating a canal wall-up mastoidectomy. A surgeon with extensive experience in surgery of the petrous bone performed the mastoidectomy. The operative field included the mastoid, with its substantial differences in density between the cortex and the pneumatized bone, together with soft tissue structures, both on the border and inside the bone. The simulation is better in the first part of the operation than in the second part, suffering from a lack of haptic feedback from soft tissue and the surgical tool in deeper contexts, and under-representation of the variability inherent in pneumatized bone. This said, the excellent representation of dust production and removal, 3D simulation through color, and very good visual and haptic feedback in the early stage of the procedure are impressive. IERAPSI represents a potential surgical planning theater for the training of students and young surgeons, but is also expected to aid expert surgeons in the preoperative planning of difficult cases.

  16. Fibromyxoma of the Lateral Skull Base in a Child: Case Report

    PubMed Central

    Klimo, Paul; Jha, Tushar; Choudhri, Asim F.; Joyner, Royce; Michael, L. Madison

    2013-01-01

    Purpose Fibromyxomas and myxomas are benign tumors of mesenchymal origin usually found outside the nervous system, most commonly in the atrium of the heart. They can also arise in the mandible or maxilla, but it is exceedingly rare to find them within the skull base. The history, histologic features, and the literature, with emphasis on other pediatric cases, are reviewed for this uncommon skull base neoplasm. Methods We describe the case of a 13-year-old girl who presented with a 1-year history of facial weakness, numbness, and hearing loss. A large locally destructive tumor centered in the petrous bone was found on magnetic resonance imaging. Results A mastoidectomy combined with a middle fossa craniotomy was performed for gross total resection. The child is disease free 12 months after surgery. Conclusion Diagnosis could not be made solely on radiographic studies because of the lack of pathognomonic imaging features. Radical resection provided the patient the best chance of cure. Long-term surveillance is necessary to monitor for tumor recurrence. PMID:24303345

  17. Abducens nerve palsy due to inferior petrosal sinus thrombosis.

    PubMed

    Mittal, Shivam Om; Siddiqui, Junaid; Katirji, Bashar

    2017-02-24

    Isolated unilateral abducens nerve palsy is usually due to ischemia, trauma or neoplasm. Dorello's canal is the space between the petrous apex and superolateral portion of the clivus, bound superiorly by Gruber's ligament. The abducens nerve travels with inferior petrosal sinus (IPS) though the Dorello's canal before entering the cavernous sinus. A 31-year-old man presented with neck pain, and binocular horizontal diplopia, worse looking towards left and at distance. He had a history of intravenous drug abuse but no history of hypertension or diabetes. On examination, he had complete left 6th nerve palsy with normal fundi, pupils, and other cranial nerves. Methicillin-resistant Staphylococcus aureus bacteremia was detected with naïve tricuspid valve endocarditis and multiple septic emboli to lungs with infarcts. His cerebrospinal fluid was normal. MRI of the brain was normal. MRV of head and neck showed thrombosis of the left internal jugular vein, left sigmoid sinus and left inferior petrosal sinus with normal cavernous sinus and no evidence of mastoiditis. He was treated with broad spectrum antibiotics. He was not anticoagulated for fear of pulmonary hemorrhage from pulmonary infarcts. Although cerebral venous sinus thrombosis commonly presents with elevated intracranial pressure, isolated ipsilateral 6th nerve palsy from its compression in Dorello's canal due to thrombosis of the ipsilateral inferior petrosal sinus is extremely rare. To our knowledge, only two patients have been reported with isolated abducens palsy due to IPS thrombosis; one caused by septic emboli and the other developed it during IPS cortisol level sampling.

  18. What Is Expected of the Facial Nerve in Michel Aplasia? Anatomic Variation

    PubMed Central

    Zarandy, Masoud Motasaddi; Kouhi, Ali; Kashany, Shervin Sharif; Rabiei, Sohrab; Hajimohamadi, Fatemeh; Rabbani-Anari, Mahtab

    2010-01-01

    We sought better understanding about the facial nerve anatomy in the rare inner ear Michel anomaly to help better define this aplasia and prevent potential complications in surgery on these patients. The data from computed tomography scans and magnetic resonance images of six Michel aplastic ears (three patients) were evaluated for a facial nerve course. Facial nerve course and anatomic landmarks were noted. Based on data obtained from this group of very rare patients, three different facial nerve anatomies were encountered. The first patient had normal-looking mastoid cells, normal middle ear ossicles, and a completely formed facial nerve canal through the middle ear. The second patient had pneumatized mastoid air cells despite an anomalous ossicular chain. This patient also had a facial nerve canal but not through the middle ear. In the third patient, although mastoid cells were present, neither ossicles nor a definite facial nerve canal could be detected. With guidance provided by the anatomy of the other parts of the ear, such as air cells and the ossicular chain, the danger zones posing a high probability of facial nerve injury can be predicted. Although all Michel aplasias may have aplastic petrous bone in common, there are some degrees of variation. PMID:21772803

  19. Anterior Petrosectomy: Consecutive Series of 46 Patients with Attention to Approach-Related Complications

    PubMed Central

    Gompel, Jamie J. Van; Alikhani, Puya; Youssef, A. Samy; Loveren, Harry R. van; Boyev, K. Paul; Agazzi, Sivero

    2015-01-01

    Objective Anterior petrosectomy(AP) was popularized in the 1980s and 1990s as micro-neurosurgery proliferated. Original reports concentrated on the anatomy of the approach and small case series. Recently, with the advent of additional endonasal approaches to the petrous apex, the morbidity of AP remains unclear. This report details approach-related morbidity around and under the temporal lobe. Methods A total of 46 consecutive patients identified from our surgical database were reviewed retrospectively. Results Of the 46 patients, 61% were women. Median age of the patients was 50 years (mean: 48 ± 2 years). Median follow-up of this cohort was 66 months. Most procedures dealt with intradural pathology (n = 40 [87%]). Approach-related morbidity consisted of only two patients (4%) with new postoperative seizures. There were only two significant postoperative hemorrhages (4%). Cerebrospinal fluid leakage occurred in two patients (4%) requiring reoperation. Conclusion Approach-related complications such as seizures and hematoma were infrequent in this series, < 4%. This report describes a contemporary group of patients treated with open AP and should serve as a comparison for approach-related morbidity of endoscopic approaches. Given the pathologies treated with this approach, the morbidity appears acceptable. PMID:26401480

  20. Clinical controversy in orbitary cholesteatoma.

    PubMed

    Rosca, Tatiana; Bontas, Ecaterina; Vladescu, Teodora Gh; St Tihoan, Cecilia; Gherghescu, Gheorghe

    2006-04-01

    Cholesterol granulomas are tumor-like lesions very rarely encountered in the orbital, frontal sinus, and maxillary sinus sites but with higher frequency in the middle-ear and petrous apex. Theoretically, cholesterol granulomas develop as a reaction to localized hemorrhages, often occurring in bony sites with no blood and blood products drainage. We present 5 cases with exophthalmoses, namely, 3 cases with granuloma and 2 cases with cholesteatoma, all being characterized by the presence of cholesterol spikes at the histologic examination. Henderson (Orbital tumors. 3rd ed. New York: Raven Press; 1994) reports cholesterol spikes in medical literature as structures with different histologic names as hematic cyst, intraorbital hematoma, subperiostal hemorrhages, chocolate cyst, and xanthomatosis reactive lesions of bone. In fact, cholesterol granuloma is the term for the pocket of hematogenous debris found in the frontal bone at surgery. We try to review the spectrum of clinical-pathological and radiographic features that characterize cholesterol granuloma but with the same surgical way management.

  1. Anterior Petrosectomy: Consecutive Series of 46 Patients with Attention to Approach-Related Complications.

    PubMed

    Van Gompel, Jamie J; Alikhani, Puya; Youssef, A Samy; Loveren, Harry R van; Boyev, K Paul; Agazzi, Sivero

    2015-09-01

    Objective Anterior petrosectomy(AP) was popularized in the 1980s and 1990s as micro-neurosurgery proliferated. Original reports concentrated on the anatomy of the approach and small case series. Recently, with the advent of additional endonasal approaches to the petrous apex, the morbidity of AP remains unclear. This report details approach-related morbidity around and under the temporal lobe. Methods A total of 46 consecutive patients identified from our surgical database were reviewed retrospectively. Results Of the 46 patients, 61% were women. Median age of the patients was 50 years (mean: 48 ± 2 years). Median follow-up of this cohort was 66 months. Most procedures dealt with intradural pathology (n = 40 [87%]). Approach-related morbidity consisted of only two patients (4%) with new postoperative seizures. There were only two significant postoperative hemorrhages (4%). Cerebrospinal fluid leakage occurred in two patients (4%) requiring reoperation. Conclusion Approach-related complications such as seizures and hematoma were infrequent in this series, < 4%. This report describes a contemporary group of patients treated with open AP and should serve as a comparison for approach-related morbidity of endoscopic approaches. Given the pathologies treated with this approach, the morbidity appears acceptable.

  2. Percutaneous inner-ear access via an image-guided industrial robot system.

    PubMed

    Baron, S; Eilers, H; Munske, B; Toennies, J L; Balachandran, R; Labadie, R F; Ortmaier, T; Webster, R J

    2010-01-01

    Image-guided robots have been widely used for bone shaping and percutaneous access to interventional sites. However, due to high-accuracy requirements and proximity to sensitive nerves and brain tissues, the adoption of robots in inner-ear surgery has been slower. In this paper the authors present their recent work towards developing two image-guided industrial robot systems for accessing challenging inner-ear targets. Features of the systems include optical tracking of the robot base and tool relative to the patient and Kalman filter-based data fusion of redundant sensory information (from encoders and optical tracking systems) for enhanced patient safety. The approach enables control of differential robot positions rather than absolute positions, permitting simplified calibration procedures and reducing the reliance of the system on robot calibration in order to ensure overall accuracy. Lastly, the authors present the results of two phantom validation experiments simulating the use of image-guided robots in inner-ear surgeries such as cochlear implantation and petrous apex access.

  3. Java brucea and Chinese herbal medicine for the treatment of cholesterol granuloma in the suprasellar and sellar regions

    PubMed Central

    Sun, Zhe; Cao, Yang; Zhai, Lin-zhu

    2017-01-01

    Abstract Rationale: A cholesterol granuloma (CG) is usually found in the middle ear, papilla, orbits, petrous apex, and choroid plexus, but is highly uncommon in the skull. In spite of benign clinicopathological lesions, bone erosion can be seen occasionally in the patient with CG. The optimal treatment strategy is radical surgery, but complete excision is usually impossible due to anatomical restrictions and a risk of injury to the key structures located nearby. Here, we report a patient with CGs in the suprasellar and sellar regions who was successfully treated with Java brucea and Chinese herbal medicine. Patient concerns: A 31-year-old man presenting with progressive decreased vision in both eyes was analyzed. Diagnoses: A skull magnetic resonance imaging (MRI) scan showed a low-density tumor in the uprasellar and sellar regions and histopathological examination revealed a CG. Interventions: The patient was referred the surgery and radiotherapy. In the meantime, brucea soft capsules and herbal medicine combined were administered to him. Outcomes: The related clinical symptoms and signs resolved significantly after several months, as his therapy progressed. The patient showed no sign of recurrence during the treatment period. Furthermore, he was still alive and disease-free at 37 months of follow-up visit. Lessons: Overall, brucea soft capsules and a Chinese herbal formula treatment combined could be beneficial in improving the patient's quality of life with CG in the skull. PMID:28151875

  4. Contralateral Cochlear Labyrinthine Concussion without Temporal Bone Fracture: Unusual Posttraumatic Consequence

    PubMed Central

    Méndez, D.; Silva, J. M. Duque; del Álamo, P. Ortega

    2016-01-01

    Introduction. Labyrinthine concussion is a term used to describe a rare cause of sensorineural hearing loss with or without vestibular symptoms occurring after head trauma. Isolated damage to the inner ear without involving the vestibular organ would be designated as a cochlear labyrinthine concussion. Hearing loss is not a rare finding in head trauma that involves petrous bone fractures. Nevertheless it generally occurs ipsilateral to the side of the head injury and extraordinarily in the contralateral side and moreover without the presence of a fracture. Case Report. The present case describes a 37-year-old patient with sensorineural hearing loss and tinnitus in his right ear after a blunt head trauma of the left-sided temporal bone (contralateral). Otoscopy and radiological images showed no fractures or any abnormalities. A severe sensorineural hearing loss was found in his right ear with a normal hearing of the left side. Conclusion. The temporal bone trauma requires a complete diagnostic battery which includes a neurotologic examination and a high resolution computed tomography scan in the first place. Hearing loss after a head injury extraordinarily occurs in the contralateral side of the trauma as what happened in our case. In addition, the absence of fractures makes this phenomenon even more unusual. PMID:27738540

  5. Dorello's Canal for Laymen: A Lego-Like Presentation

    PubMed Central

    Ezer, Haim; Banerjee, Anirban Deep; Thakur, Jai Deep; Nanda, Anil

    2012-01-01

    Objective Dorello's canal was first described by Gruber in 1859, and later by Dorello. Vail also described the anatomy of Dorello's canal. In the preceding century, Dorello's canal was clinically important, in understanding sixth nerve palsy and nowadays it is mostly important for skull base surgery. The understanding of the three dimensional anatomy, of this canal is very difficult to understand, and there is no simple explanation for its anatomy and its relationship with adjacent structures. We present a simple, Lego-like, presentation of Dorello's canal, in a stepwise manner. Materials and Methods Dorello's canal was dissected in five formalin-fixed cadaver specimens (10 sides). The craniotomy was performed, while preserving the neural and vascular structures associated with the canal. A 3D model was created, to explain the canal's anatomy. Results Using the petrous pyramid, the sixth nerve, the cavernous sinus, the trigeminal ganglion, the petorclival ligament and the posterior clinoid, the three-dimensional structure of Dorello's canal was defined. This simple representation aids in understanding the three dimensional relationship of Dorello's canal to its neighboring structures. Conclusion Dorello's canal with its three dimensional structure and relationship to its neighboring anatomical structures could be reconstructed using a few anatomical building blocks. This method simplifies the understanding of this complex anatomical structure, and could be used for teaching purposes for aspiring neurosurgeons, and anatomy students. PMID:23730547

  6. A Combined Intradural Presigmoid-Transtransversarium-Transcondylar Approach to the Whole Clivus and Anterior Craniospinal Region

    PubMed Central

    Ammirati, Mario; Ma, Jianya; Canalis, Rinaldo; Martin, Neil; Black, Keith; Cheatham, Mel; Bloch, Joseph; Becker, Donald

    1993-01-01

    Surgical exposure of the clivus is difficult because of its proximity to vital neurovascular structures. The anatomic bases of a new surgical approach to this area are discussed. A supra-auricular skin incision is extended toward the posterior border of the sternocleidomastoid muscle. The vertebral artery is exposed from C2 to the occiput unroofing the foramen transversarium of C1. The bone removal consists of a posterior temporal craniotomy, a suboccipital craniectomy, including mastoidectomy with sigmoid sinus unroofing, removal of the lateral margin of the foramen magnum, of the medial third of the occipital condyle, and retrolabyrinthine petrous drilling. Posterior retraction of the vertebral artery facilitates occipital condyle drilling. Intradural exposure of the petroclival region is achieved by L-shaped cutting of the dura with the long branch placed infratentorially anterior to the sigmoid sinus. Intradural exposure of the craniospinal/upper cervical areas is achieved by cutting of the dura medial to the distal sigmoid sinus and by longitudinal cutting of the dura anterior to the vertebral artery. This approach allows multiple ports of entry to the clivus with full control of the vertebrobasilar system, and of the dural sinuses, and is anatomically suited for controlled removal of tumors located in these areas. This approach, or segments of it, has been used successfully in the treatment of large neoplasms of the craniovertebral junction. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5Figure 6Figure 7Figure 8Figure 9Figure 10Figure 11 PMID:17170911

  7. Ardipithecus ramidus and the evolution of the human cranial base

    PubMed Central

    Kimbel, William H.; Suwa, Gen; Asfaw, Berhane; Rak, Yoel; White, Tim D.

    2014-01-01

    The early Pliocene African hominoid Ardipithecus ramidus was diagnosed as a having a unique phylogenetic relationship with the Australopithecus + Homo clade based on nonhoning canine teeth, a foreshortened cranial base, and postcranial characters related to facultative bipedality. However, pedal and pelvic traits indicating substantial arboreality have raised arguments that this taxon may instead be an example of parallel evolution of human-like traits among apes around the time of the chimpanzee–human split. Here we investigated the basicranial morphology of Ar. ramidus for additional clues to its phylogenetic position with reference to African apes, humans, and Australopithecus. Besides a relatively anterior foramen magnum, humans differ from apes in the lateral shift of the carotid foramina, mediolateral abbreviation of the lateral tympanic, and a shortened, trapezoidal basioccipital element. These traits reflect a relative broadening of the central basicranium, a derived condition associated with changes in tympanic shape and the extent of its contact with the petrous. Ar. ramidus shares with Australopithecus each of these human-like modifications. We used the preserved morphology of ARA-VP 1/500 to estimate the missing basicranial length, drawing on consistent proportional relationships in apes and humans. Ar. ramidus is confirmed to have a relatively short basicranium, as in Australopithecus and Homo. Reorganization of the central cranial base is among the earliest morphological markers of the Ardipithecus + Australopithecus + Homo clade. PMID:24395771

  8. Ardipithecus ramidus and the evolution of the human cranial base.

    PubMed

    Kimbel, William H; Suwa, Gen; Asfaw, Berhane; Rak, Yoel; White, Tim D

    2014-01-21

    The early Pliocene African hominoid Ardipithecus ramidus was diagnosed as a having a unique phylogenetic relationship with the Australopithecus + Homo clade based on nonhoning canine teeth, a foreshortened cranial base, and postcranial characters related to facultative bipedality. However, pedal and pelvic traits indicating substantial arboreality have raised arguments that this taxon may instead be an example of parallel evolution of human-like traits among apes around the time of the chimpanzee-human split. Here we investigated the basicranial morphology of Ar. ramidus for additional clues to its phylogenetic position with reference to African apes, humans, and Australopithecus. Besides a relatively anterior foramen magnum, humans differ from apes in the lateral shift of the carotid foramina, mediolateral abbreviation of the lateral tympanic, and a shortened, trapezoidal basioccipital element. These traits reflect a relative broadening of the central basicranium, a derived condition associated with changes in tympanic shape and the extent of its contact with the petrous. Ar. ramidus shares with Australopithecus each of these human-like modifications. We used the preserved morphology of ARA-VP 1/500 to estimate the missing basicranial length, drawing on consistent proportional relationships in apes and humans. Ar. ramidus is confirmed to have a relatively short basicranium, as in Australopithecus and Homo. Reorganization of the central cranial base is among the earliest morphological markers of the Ardipithecus + Australopithecus + Homo clade.

  9. Coexistence of intracranial epidermoid tumor and multiple cerebral aneurysms

    PubMed Central

    Yao, Pei-Sen; Lin, Zhang-Ya; Zheng, Shu-Fa; Lin, Yuan-Xiang; Yu, Liang-Hong; Jiang, Chang-Zhen; Kang, De-Zhi

    2017-01-01

    Abstract Rationale: There were a few case reports concerning epidermoid tumor coexisted with multiple cerebral aneurysms. Here, we present one case of coexistence of intracranial epidermoid tumor and multiple cerebral aneurysms and performed a literature review. Patient concerns: A 42 years old male patient was admitted to our institution with complaints of headache and dizziness. Interventions: The radiological examinations showed a hypointense lesion in the right parasellar and petrous apex region and an ipsilateral saccular aneurysm originated from the M2–M3 junction of the right middle cerebral artery (MCA) and a saccular aneurysm of the clinoid segment of right internal carotid artery (ICA). Interventions: The patients underwent a right frontotemporal approach for removal of the epidermoid tumor and clipping of the MCA aneurysm in one stage. The aneurysm located at the clinoid segment of ICA was invisible and untreated during operation. Outcomes: No postoperative complications were found in the patient. The patient's follow up after 5 years of surgical treatment was uneventful, and the untreated aneurysm remains stable. Lessons: The coexistence of intracranial epidermoid tumor and cerebral aneurysm is a rare event. The secondly inflammation in cerebral arterial wall may be responsible for the aneurysm formation. Surgical treatment of the intracranial epidermoid tumor and cerebral aneurysm repair may be an optimal scheme in one stage. PMID:28151901

  10. Quantitative analysis of the cochlea using three-dimensional reconstruction based on microcomputed tomographic images.

    PubMed

    Shin, Kang-Jae; Lee, Ju-Young; Kim, Jeong-Nam; Yoo, Ja-Young; Shin, Chuog; Song, Wu-Chul; Koh, Ki-Seok

    2013-07-01

    The aim of this study was to provide data on various dimensions of the normal cochlea using three-dimensional reconstruction based on high-resolution micro-CT images. The petrous parts of 39 temporal bones were scanned by micro-computed tomography (CT) with a slice thickness of 35 μm. The micro-CT images were used in reconstructing three-dimensional volumes of the bony labyrinth using computer software. The volumes were used to measure 12 dimensions of the cochlea, and statistical analysis was carried out. The dimensions of cochleae varied widely between different specimens. The mean height and length of the cochlea were 3.8 and 9.7 mm, respectively. The angle between the basal and middle turns was slightly larger in males than in females, while none of the other 11 dimensions differed significantly between males and females. The cochlear accessory canals were observed in about half of the cases (51.3%). Correlation analysis among measured items revealed positive correlations among several of the measured dimensions. The present study could investigate the detailed anatomy of the normal cochlea using high-resolution imaging technologies. The results of the present study could be helpful for the precise diagnosis of congenital cochlear malformations and for producing optimized cochlear implants.

  11. In vivo testing of a bioabsorbable magnesium alloy serving as total ossicular replacement prostheses.

    PubMed

    Lensing, Rebecca; Behrens, Peter; Müller, Peter Paul; Lenarz, Thomas; Stieve, Martin

    2014-01-01

    Magnesium alloys have been investigated in different fields of medicine and represent a promising biomaterial for implants due to characteristics like bioabsorbability and osteoinduction. The objective of this study was to evaluate the usability of magnesium as implant material in middle ear surgery. Magnesium implants were placed into the right middle ear of eighteen New Zealand White rabbits. Nine animals were euthanized after four weeks and nine animals after three month. The petrous bones were removed and embedded in epoxy resin. The specimens were then polished, stained and evaluated with the aid of a light microscope. The histological examination revealed a good biocompatibility. After four weeks, a beginning corrosion of the implant's surface and low amount of trabecular bone formation in the area of the stapes base plate was observed. A considerable degradation of implants and obvious bone formation was found three month after implantation. The magnesium alloy used in the present study partly corroded too fast, so that a complete bone reconstruction could not be established in time. The increased osteoinduction on the stapes base plate resulted in a tight bone-implant bonding. Thus, a promising application of magnesium could be a coating of biomaterials in order to improve the bony integration of implants.

  12. Langerhans cell histiocytosis with multifocal bone lesions: comparative clinical features between single and multi-systems.

    PubMed

    Imashuku, Shinsaku; Kinugawa, Naoko; Matsuzaki, Akinobu; Kitoh, Toshiyuki; Ohki, Kentaro; Shioda, Yoko; Tsunematsu, Yukiko; Imamura, Toshihiko; Morimoto, Akira

    2009-11-01

    Langerhans cell histiocytosis (LCH) can be a single system or multi-system disease. Both disease types can be associated with multi-focal bone lesions, but their bone involvement patterns have not been compared systematically. Of the new pediatric LCH cases enrolled into the JLSG-02 study during 2002-2007, 67 cases of single system multifocal bone (SMFB) LCH and 97 cases of multi-system bone (MSB) LCH were analyzed to determine if the bone involvement patterns differ in these two types, and whether these differences correlate with outcome. Statistical analysis was performed with Mann-Whitney U test, Fisher's exact test, and other measures. Onset ages were higher for SMFB (P < 0.001), but the two types did not differ in the number of bone lesions per patient. The skull was most frequently affected in both types, followed by the spine. Lesions in the temporal bone (P = 0.002), ear-petrous bone (P < 0.001), orbita (P = 0.003), and zygomatic bone (P = 0.016) were significantly more common in MSB. The two types did not differ in response to treatment, but MSB was associated with a significantly higher incidence of diabetes insipidus (DI) (P < 0.001). Novel measures are required in preventing the development of DI in MSB-type LCH patients with "risk" bone lesions.

  13. Microsurgical treatment of tentorial meningiomas: Report of 30 patients

    PubMed Central

    Aguiar, Paulo Henrique; Tahara, Adriana; de Almeida, Antonio Nogueira; Kurisu, Kaoru

    2010-01-01

    Background: Tentorial meningiomas represent about 5% of intracranial meningiomas. This article reviews our recent institutional series of patients with tentorial meningiomas, proposes a simplified classification and analyzes postoperative evolution, discussing the salient features in the management of these patients. Methods: From 1998 to 2005, 30 patients (22 female and 8 male) with tentorial meningiomas were operated at our institution. Thirteen patients had tumor restricted to the infratentorial space; 12, to the supratentorial space; and in 5 cases, the tumor involved both compartments. Follow-up ranged from 1 to 8 years. A total of 35 surgical procedures were performed in 30 patients, where 26 procedures were performed through a single approach (2, ITSC; 10, RS; 5, SOIH; 5, ST; and 4, TT); and 9, through combined approaches (7, ITSC/ SOIH; and 2, RS/ST). Results: Simpson I resection was achieved in 17 patients. Tumors involving both compartments, involving the petrous sinus, and attached to the torcula limited complete resection. Twenty-two out of 30 patients were able to return to their regular life with no or minimal neurological sequelae. Most frequent complications in our series were shunt dependence, CSF fistulae, diffuse brain injury and visual field defects. Overall, our series revealed 3% mortality and 23% morbidity. Conclusion: Tentorial meningiomas are associated with significant morbidity related to the nervous and vascular structures surrounding the tumor. Partial tumor removal may be necessary in some cases. PMID:20847917

  14. Internal carotid artery stenosis associated with giant cell arteritis: case report and discussion

    PubMed Central

    Zarar, Amna; Zafar, Taqi T; Khan, Asif A; Suri, M Fareed K; Qureshi, Adnan I

    2014-01-01

    Background Cerebrovascular ischemic events associated with giant cell arteritis (GCA) are uncommon and have been reported in 3%–4% of patients. We describe a case report of GCA associated with intracranial stenosis and review various angiographic findings. Case presentation A 66-year-old man presented with worsening headache and vision loss. A recent magnetic resonance angiogram of the head and neck showed multiple intracranial stenosis. Cerebrospinal fluid (CSF) analysis demonstrated increased protein of 135.6 mg/dL, with two white blood cells/µL. No bacteria were observed in the CSF on gram staining, and cultures were negative for bacterial growth. Erythrocyte sedimentation rate was noted to be 14 mm/h, and C-reactive protein was 1.514 mg/L at admission. Human immunodeficiency virus (HIV) and hepatitis panels were negative. On digital subtraction angiography, patient had predominantly narrowing and irregularities in petrous and cavernous segments of the internal carotid arteries bilaterally. The diagnosis of GCA was confirmed by temporal artery biopsy. He was treated with steroids, and a followup angiogram 6 weeks later showed minimal resolution of the angiographic findings. Patient reported complete resolution of headaches and visual loss. Conclusion Bilateral internal carotid arteries stenosis may be seen in patients presenting with typical symptoms of GCA and may persist after steroid treatment despite resolution of clinical symptoms. PMID:25566338

  15. Endovascular treatment of an infected pseudoaneurysm secondary to retropharyngeal abscess in a child

    PubMed Central

    Diehn, Felix E; Lindsay, Christopher W; Morris, Jonathan M

    2015-01-01

    We describe a rare case of carotid pseudoaneurysm secondary to a retropharyngeal abscess, treated with coil embolization in a 2-year-old boy. The patient presented to an emergency department with symptoms suggesting meningitis but was subsequently diagnosed with streptococcal pharyngitis. He was discharged home on oral antibiotics after a short hospitalization. He returned to the emergency department two weeks later with limited neck motion and pain. Neck CT demonstrated a retropharyngeal abscess with a large left cervical internal carotid artery (ICA) pseudoaneurysm. The petrous ICA distal to the pseudoaneurysm had thrombosed prior to treatment. The ICA proximal to the pseudoaneurysm was sacrificed with coil embolization. Post-treatment imaging demonstrated complete thrombosis of the pseudoaneurysm but also demonstrated acute strokes in the left MCA/ACA watershed distribution. His parents noted that the patient was clumsier and exhibited some mild speech changes and a steppage gait prior to evaluation in the ED; therefore, these were thought to be secondary to emboli from partial thrombosis of the pseudoaneurysm prior to treatment. The patient was discharged home in good condition and his neurological function improved. PMID:26060279

  16. Aneurysmal Bone Cyst of the Temporal Bone Presenting with Headache and Partial Facial Palsy

    PubMed Central

    Kletke, Stephanie N.; Popovic, Snezana; Algird, Almunder; Alobaid, Abdullah; Reddy, Kesava K. V.

    2015-01-01

    Background Aneurysmal bone cysts (ABCs) are benign bony lesions that rarely affect the skull base. Very few cases of temporal bone ABCs have been reported. We describe the first case of a temporal bone ABC that was thought to be consistent with a meningioma based on preoperative magnetic resonance imaging (MRI) findings. Clinical Presentation An otherwise healthy 23-year-old woman presented with a pulsatile noise in her left ear and a 4-week history of throbbing headache with nausea. There was no associated emesis, visual or auditory changes, or other neurologic features. Neurologic examination revealed a left lower motor neuron facial paresis. Computed tomography and MRI studies demonstrated a large lesion in the left middle cranial fossa skull base with erosion of the petrous temporal bone. Based on the presence of a “dural tail” on preoperative contrast-enhanced T1-weighted imaging, the lesion was interpreted to likely be consistent with a meningioma. An orbitozygomatic approach was utilized for surgical excision. Histopathologic evaluation was consistent with an ABC. Conclusion Postoperatively the patient had improvement in the lower motor neuron facial paresis. It is important to consider ABC in the differential diagnosis of intracranial lesions accompanied by the dural tail sign on MRI. PMID:26251800

  17. Closure of the middle ear with special reference to the development of the tegmen tympani of the temporal bone

    PubMed Central

    Rodríguez-Vázquez, José Francisco; Murakami, Gen; Verdugo-López, Samuel; Abe, Shin-ichi; Fujimiya, Mineko

    2011-01-01

    Closure of the middle ear is believed to be closely related to the evolutionary development of the mammalian jaw. However, few comprehensive descriptions are available on fetal development. We examined paraffin-embedded specimens of 20 mid-term human fetuses at 8–25 weeks of ovulation age (crown-rump length or CRL, 38–220 mm). After 9 weeks, the tympanic bone and the squamous part of the temporal bone, each of which was cranial or caudal to Meckel's cartilage, grew to close the lateral part of the tympanosquamosal fissure. At the same time, the cartilaginous tegmen tympani appeared independently of the petrous part of the temporal bone and resulted in the petrosquamosal fissure. Subsequently, the medial part of the tympanosquamosal fissure was closed by the descent of a cartilaginous inferior process of the tegmen tympani. When Meckel's cartilage changed into the sphenomandibular ligament and the anterior ligament of the malleus, the inferior process of the tegmen tympani interposed between the tympanic bone and the squamous part of the temporal bone, forming the petrotympanic fissure for the chorda tympani nerve and the discomalleolar ligament. Therefore, we hypothesize that, in accordance with the regression of Meckel's cartilage, the rapidly growing temporomandibular joint provided mechanical stress that accelerated the growth and descent of the inferior process of the tegmen tympani via the discomalleolar ligament. The usual diagram showing bony fissures around the tegmen tympani may overestimate the role of the tympanic bone in the fetal middle-ear closure. PMID:21477146

  18. Dangerous extracranial-intracranial anastomoses and supply to the cranial nerves: vessels the neurointerventionalist needs to know.

    PubMed

    Geibprasert, S; Pongpech, S; Armstrong, D; Krings, T

    2009-09-01

    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).

  19. Schwannoma originating from lower cranial nerves: report of 4 cases.

    PubMed

    Oyama, Hirofumi; Kito, Akira; Maki, Hideki; Hattori, Kenichi; Noda, Tomoyuki; Wada, Kentaro

    2012-02-01

    Four cases of schwannoma originating from the lower cranial nerves are presented. Case 1 is a schwannoma of the vagus nerve in the parapharyngeal space. The operation was performed by the transcervical approach. Although the tumor capsule was not dissected from the vagus nerve, hoarseness and dysphagia happened transiently after the operation. Case 2 is a schwannoma in the jugular foramen. The operation was performed by the infralabyrinthine approach. Although only the intracapsular tumor was enucleated, facial palsy, hoarseness, dysphagia and paresis of the deltoid muscle occurred transiently after the operation. The patient's hearing had also slightly deteriorated. Case 3 is a dumbbell-typed schwannoma originating from the hypoglossal nerve. The hypoglossal canal was markedly enlarged by the tumor. As the hypoglossal nerves were embedded in the tumor, the tumor around the hypoglossal nerves was not resected. The tumor was significantly enlarged for a while after stereotactic irradiation. Case 4 is an intracranial cystic schwannoma originating from the IXth or Xth cranial nerves. The tumor was resected through the cerebello-medullary fissure. The tumor capsule attached to the brain stem was not removed. Hoarseness and dysphagia happened transiently after the operation. Cranial nerve palsy readily occurs after the removal of the schwannoma originating from the lower cranial nerves. Mechanical injury caused by retraction, extension and compression of the nerve and heat injury during the drilling of the petrous bone should be cautiously avoided.

  20. Retrospective correction of B0-field-induced geometric distortions in multislice echo planar images: a 3D solution

    NASA Astrophysics Data System (ADS)

    McColl, Roderick W.; Coburn, Edward A.

    2000-04-01

    A method has been developed to utilize a 3D B0 fieldmap, with a multi-volume-of-interest segmentation map, to quantify and correct geometric distortions in echo-planar images. The purpose is to provide accurate co-registration of anatomical MRI to functional MRI time course sequences. A data structure capable of extracting and reporting the necessary information forms a central part of the solution. Images were obtained from a 1.5 Tesla scanner with an experimental y-gradient insert coil. Two 3D-gradient echo sequences supply the data needed to calculate the B0 map across the volume. Segmentation of the volume into brain/background produces the data needed for the phase unwrapping and volume(s) of interest generation, from which the global B0 variation map is obtained. Subsequent EPI acquisition yields the fMRI time- course information. Tests were carried out on a phantom and a human volunteer engaged in a motor task (finger-tapping). Strong distortions were measured, and subsequently corrected, particularly near the petrous bone/mastoid air cells and in the frontal and maxillary sinuses. Additionally, a strong eddy current resulting from the unshielded y-gradient was detected. The method facilitates geometric distortion correction through an imaging volume, containing multiple regions of interest within a slice, starting from a single starting point.

  1. Prevention of cerebrospinal fluid leakage and delayed loss of preserved hearing after vestibular schwannoma removal: reconstruction of the internal auditory canal in the suboccipital transmeatal approach--technical note.

    PubMed

    Yamakami, I; Kobayashi, E; Ono, J; Yamaura, A

    2000-11-01

    The suboccipital transmeatal approach uses packing of a muscle or fat graft into the internal auditory canal (IAC) to prevent postoperative cerebrospinal fluid (CSF) leakage. However, preserved hearing after removal of vestibular schwannomas may decline over time because of the progressive constriction of cochlear vascular supply due to scarring of the IAC. We propose a surgical technique for IAC reconstruction, which separates the preserved cochlear nerve and vasculature from the graft, and regains the CSF space in the IAC. Prior to the drilling of the posterior wall of the IAC, the dura mater of the petrous bone forming the posterior wall of the IAC is harvested for IAC reconstruction. After completion of tumor removal, a "roof" of the IAC is reconstructed using the dura mater, and a muscle or fat graft soaked with fibrin glue is placed on the "roof" of the IAC. The IAC was reconstructed using this technique in 26 consecutive patients with vestibular schwannomas who underwent tumor removal via the suboccipital transmeatal approach. Postoperative magnetic resonance imaging confirmed the regained CSF space in the IAC. No delayed hearing loss occurred in four patients with preserved hearing. No CSF leakage occurred after surgery. This new technique of IAC reconstruction may prevent delayed hearing loss as well as postoperative CSF leakage after removal of vestibular schwannomas via the suboccipital transmeatal approach.

  2. Rerouting of the intratemporal facial nerve: an analysis of the literature.

    PubMed

    Selesnick, S H; Abraham, M T; Carew, J F

    1996-09-01

    Anterior rerouting of the intratemporal facial nerve in the infratemporal fossa approach is employed to access to the jugular bulb, hypotympanum, and lateral skull base, whereas posterior rerouting of the facial nerve, as employed in the transcochlear craniotomy, is most frequently used for surgery of the posterior fossa, cerebellopontine angle, prepontine region, and petrous apex. Facial nerve rerouting may lead to facial paresis or paralysis. This review of the literature is intended to define the physiologic "cost" of these procedures, so that the neurotologic surgeon can determine if the morbidity incurred in these techniques is worth the resultant exposure. Inconsistencies in reporting facial function places into question the validity of some of the cumulative data reported. Postoperatively, grades I-II facial nerve function was seen in 91% of patients undergoing short anterior rerouting, 74% of patients undergoing long anterior rerouting, and 26% of patients undergoing posterior complete rerouting. Although facial nerve rerouting allows unhindered exposure to previously inaccessible regions, it is achieved at the cost of facial nerve function. Facial nerve dysfunction increases with the length of facial nerve rerouted.

  3. Surgical Anatomy of the Extended Middle Cranial Fossa Approach

    PubMed Central

    Arìstegui, Miguel; Cokkeser, Yasar; Saleh, Essam; Naguib, Maged; Landolfi, Mauro; Taibah, Abdel; Sanna, Mario

    1994-01-01

    The extended middle cranial fossa approach includes removal of the petrous bone from its subtemporal surface in order to expose widely the internal auditory canal and the posterior fossa dura around its porus while preserving all the important and closely related anatomical structures. We have dissected 25 temporal bones and five fresh cadavers in order to define the limits of this approach. Measurements were obtained between the different structures to find reliable angles and distances that could guide working in this area. A new method of identification of the internal auditory canal is discussed based on the measurements taken. The results of the present work showed wide variations in the different structures. The arcuate eminence was coincident with the superior semicircular canal in only 48% of bones. Dehiscence of the geniculate ganglion and of the internal carotid artery was noted in 16% and 20% of specimens, respectively. The angles measured between the different structures showed great variations. However, the angle between the internal auditory canal and superior petrosal sinus was constant. Though the extended middle cranial fossa is a versatile approach, it affords a limited access to the cerebellopontine angle. A thorough understanding of the complex and variable anatomy of this area is necessary should this approach be utilized. ImagesFigure 1p183-bFigure 2Figure 3Figure 4Figure 5 PMID:17171170

  4. Dural Arteriovenous Fistula Following Translabyrinthine Resection of Cerebellopontine Angle Tumors: Report of Two Cases

    PubMed Central

    Li, Peter M.M.C.; Fischbein, Nancy J.; Do, Huy M.; Blevins, Nikolas H.

    2011-01-01

    We describe two cases of dural arteriovenous fistula (DAVF) developing in a delayed fashion after translabyrinthine resection of cerebellopontine angle tumors. Two patients in an academic tertiary referral center, a 46-year-old woman and a 67-year-old man, underwent translabyrinthine resection of a 2-cm left vestibular schwannoma and a 4-cm left petrous meningioma, respectively. Both patients subsequently developed DAVF, and in each case the diagnosis was delayed despite serial imaging follow-up. In one patient, cerebrospinal fluid diversion before DAVF was identified as the cause of her intracranial hypertension; the other patient was essentially asymptomatic but with a high risk of hemorrhage due to progression of cortical venous drainage. Endovascular treatment was effective but required multiple sessions due to residual or recurrent fistulas. Dural arteriovenous fistula is a rare complication of translabyrinthine skull base surgery. Diagnosis requires a high index of clinical suspicion and an understanding of subtle imaging findings that may be present on follow-up studies performed for tumor surveillance. Failure to recognize this complication may lead to misguided interventions for treatment of hydrocephalus and other complications, as well as ongoing risks related to venous hypertension and intracranial hemorrhage. As this condition is generally curable with neurointerventional and/or surgical methods, timely diagnosis and treatment are essential. PMID:23984203

  5. Quantifying temporal bone morphology of great apes and humans: an approach using geometric morphometrics

    PubMed Central

    Lockwood, Charles A; Lynch, John M; Kimbel, William H

    2002-01-01

    The hominid temporal bone offers a complex array of morphology that is linked to several different functional systems. Its frequent preservation in the fossil record gives the temporal bone added significance in the study of human evolution, but its morphology has proven difficult to quantify. In this study we use techniques of 3D geometric morphometrics to quantify differences among humans and great apes and discuss the results in a phylogenetic context. Twenty-three landmarks on the ectocranial surface of the temporal bone provide a high level of anatomical detail. Generalized Procrustes analysis (GPA) is used to register (adjust for position, orientation and scale) landmark data from 405 adults representing Homo, Pan, Gorilla and Pongo. Principal components analysis of residuals from the GPA shows that the major source of variation is between humans and apes. Human characteristics such as a coronally orientated petrous axis, a deep mandibular fossa, a projecting mastoid process, and reduced lateral extension of the tympanic element strongly impact the analysis. In phenetic cluster analyses, gorillas and orangutans group together with respect to chimpanzees, and all apes group together with respect to humans. Thus, the analysis contradicts depictions of African apes as a single morphotype. Gorillas and orangutans lack the extensive preglenoid surface of chimpanzees, and their mastoid processes are less medially inflected. These and other characters shared by gorillas and orangutans are probably primitive for the African hominid clade. PMID:12489757

  6. Laser tissue interaction in the porcine otic capsule tissue model

    NASA Astrophysics Data System (ADS)

    Wong, Brian J.; Lee, Jon P.; Berns, Michael W.; White, Joel M.; Neev, Joseph

    1996-01-01

    The absence of a hard tissue model reflecting the properties of the inner and middle ear has made it difficult to draw consistent conclusions on the many experimental laser studies in ear surgery. Porcine otic capsule tissue has been studied by our group extensively in a wide variety of laser-tissue interaction studies and is an economically attractive and simple to use hard tissue source. Porcine otic capsule was harvested from the temporal bone of freshly sacrificed domestic pigs via a craniotomy approach. The technique when performed with power instruments takes less than 5 minutes and the entire otic capsule bone is removed intact as the suture line is not fused to the remaining petrous apex. The tissue specimen contains a vestibule, cochlea, oval and round windows, and internal auditory canals which can be used as an intact middle ear/inner ear system. The tissue can also be micromachined into thin slabs of bone varying for 100 - 1000 micrometers in thickness. In order to quantify more precisely the laser-tissue interactions in otic capsule, optical properties (absorption and scattering) and physical properties were determined (acoustic impedance). The tissue has been used in a wide variety of basic studies investigating the laser-tissue interactions with argon, KTP, (Nd:YAG), carbon dioxide, Ho:YAG, Er:YAG, and XeCl lasers. Porcine otic capsule is an ideal tissue on which standardized test can be performed to compare the relative effects of various laser in otosurgical models.

  7. Epidermoid cyst in Meckel's cave with unusual computed tomography and magnetic resonance imaging findings. Case report.

    PubMed

    Arai, Atsushi; Sasayama, Takashi; Koyama, Junji; Fujita, Atsushi; Hosoda, Kohkichi; Kohmura, Eiji

    2010-01-01

    A 27-year-old woman presented with headache and occasional numbness over her right face. Computed tomography revealed a hypodense mass in the middle cranial fossa and another adjacent hyperdense mass in the posterior fossa with erosion of the right petrous apex. Magnetic resonance imaging revealed the lesion in the middle cranial fossa as iso- to hypointense on T(1)-weighted and hyperintense on T(2)-weighted imaging, with peripheral enhancement after gadolinium administration, and the adjacent lesion in the posterior fossa as hyperintense on T(1)-weighted and hypointense on T(2)-weighted imaging. During surgery, these lesions mimicking two adjacent distinct tumors were revealed to connect through Meckel's cave. The hypodense lesion in the middle cranial fossa consisted of pearly-like solid contents, and the hyperdense lesion in the posterior cranial fossa consisted of viscid dark-green materials. The tumors were gross totally resected with endoscopic assistance. Histological examination confirmed that the tumor was an epidermoid cyst. The present case cyst indicates that although the diffusion-weighted imaging sequence is useful for detection of intracranial epidermoid cysts, epidermoid cysts including viscous materials with unusual radiological findings could complicate the preoperative diagnosis.

  8. The Vidian Canal: Radiological Features in Japanese Population and Clinical Implications

    PubMed Central

    MATO, David; YOKOTA, Hajime; HIRONO, Seiichiro; MARTINO, Juan; SAEKI, Naokatsu

    2015-01-01

    The vidian canal (VC), a bony tunnel in which the vidian artery and nerve pass, has been widely known as an important landmark to identify the anterior genu of the petrous carotid artery (AGPCA) especially during lateral extended endoscopic endonasal approachs (LEEEAs). The objectives of this study in the Japanese population are to describe the radiological anatomic features and relationships between VC and its surrounding structures, and discuss the clinical implications. We studied 231 high-resolution computed tomography (CT) scans with a slice thickness of 0.5 mm. All the patients had known sellar or parasellar pathologies but without any involvement of VC. The following VC-related parameters were examined: its length, relationship to AGPCA, course from the pterygopalatine fossa to the carotid canal, its position relative to the medial pterygoid plate and pneumatization pattern of the sphenoid sinus. Mean length of VC is 14.6 mm. There is more tendency of straight-running VC compared to other populations. VC locates infero-lateral to AGPCA in all the cases. The protrusion of VC and the paraclival carotid artery to the sphenoid sinus, as well as well-pneumatization of the sinus is also observed more frequently in almost a half of the population. Surgeons who perform LEEEAs in Japanese patients must know these anatomical features. The characteristics particular to Japanese populations may facilitate better identification of VC and exposure to AGPCA intraoperatively. PMID:25744352

  9. Rectal carcinoid tumor metastasis to a skull base meningioma

    PubMed Central

    Huang, Jennifer; Gupta, Amit; Badve, Chaitra; Cohen, Mark L; Wolansky, Leo J

    2016-01-01

    Carcinoid tumors are rare, slow-growing neuroendocrine tumors that most frequently develop in the gastrointestinal tract or lungs and have high potential for metastasis. Metastasis to the brain is rare, but to another intracranial tumor is extremely rare. Of the intracranial tumors, meningiomas are the most common to host metastases, which may be related to its rich vascularity and E-cadherin expression. We describe the case of a 65-year-old female with active chemotherapy-treated neuroendocrine carcinoma who presented with left-sided facial numbness, headaches, and blurry vision. Initial imaging revealed a 1 cm irregular dural-based left petrous apex mass suggestive of a meningioma that was re-imaged four months later as a rapidly enlarging, extra-axial, mass extending into the cavernous sinus, effacing Meckel’s cave that resembled a trigeminal schwannoma. Pathology revealed a carcinoid tumor metastatic to meningioma. While the mass displayed characteristic imaging findings of a schwannoma, rapid growth in the setting of known active malignancy should prompt the clinician to consider mixed pathology from metastatic disease or a more aggressive meningioma. PMID:26825133

  10. Horizontal vestibuloocular reflex evoked by high-acceleration rotations in the squirrel monkey. I. Normal responses

    NASA Technical Reports Server (NTRS)

    Minor, L. B.; Lasker, D. M.; Backous, D. D.; Hullar, T. E.; Shelhamer, M. J. (Principal Investigator)

    1999-01-01

    The horizontal angular vestibuloocular reflex (VOR) evoked by high-frequency, high-acceleration rotations was studied in five squirrel monkeys with intact vestibular function. The VOR evoked by steps of acceleration in darkness (3,000 degrees /s(2) reaching a velocity of 150 degrees /s) began after a latency of 7.3 +/- 1.5 ms (mean +/- SD). Gain of the reflex during the acceleration was 14.2 +/- 5.2% greater than that measured once the plateau head velocity had been reached. A polynomial regression was used to analyze the trajectory of the responses to steps of acceleration. A better representation of the data was obtained from a polynomial that included a cubic term in contrast to an exclusively linear fit. For sinusoidal rotations of 0.5-15 Hz with a peak velocity of 20 degrees /s, the VOR gain measured 0.83 +/- 0.06 and did not vary across frequencies or animals. The phase of these responses was close to compensatory except at 15 Hz where a lag of 5.0 +/- 0.9 degrees was noted. The VOR gain did not vary with head velocity at 0.5 Hz but increased with velocity for rotations at frequencies of >/=4 Hz (0. 85 +/- 0.04 at 4 Hz, 20 degrees /s; 1.01 +/- 0.05 at 100 degrees /s, P < 0.0001). No responses to these rotations were noted in two animals that had undergone bilateral labyrinthectomy indicating that inertia of the eye had a negligible effect for these stimuli. We developed a mathematical model of VOR dynamics to account for these findings. The inputs to the reflex come from linear and nonlinear pathways. The linear pathway is responsible for the constant gain across frequencies at peak head velocity of 20 degrees /s and also for the phase lag at higher frequencies being less than that expected based on the reflex delay. The frequency- and velocity-dependent nonlinearity in VOR gain is accounted for by the dynamics of the nonlinear pathway. A transfer function that increases the gain of this pathway with frequency and a term related to the third power of head

  11. Balloon-assisted guide catheter positioning to overcome extreme cervical carotid tortuosity: technique and case experience

    PubMed Central

    Peeling, Lissa; Fiorella, David

    2014-01-01

    Background and significance We describe a method by which to efficiently and atraumatically achieve distal positioning of a flexible guiding catheter beyond extreme cervical tortuosity using a hypercompliant temporary occlusion balloon. Methods A retrospective review of a prospective neuroendovascular database was used to identify cases in which a hypercompliant balloon catheter (Hyperform or Hyperglide, ev3/Covidien, Irvine, California, USA; Scepter or Scepter XC, Alisa Viejo, California, USA) was used to achieve distal positioning of a flexible guiding catheter (Navion, ev3/Covidien, Irvine, California, USA; Neuron, Penumbra Inc, Alameda, California, USA). After achieving a stable guiding sheath position within the proximal cervical carotid artery, a hypercompliant balloon catheter was manipulated beyond the tortuous cervical internal carotid segment into the distal carotid artery. The balloon was then inflated to anchor it distally within an intracranial (cavernous or petrous) segment of the internal carotid artery. The guiding catheter was then advanced beyond the tortuous cervical segment, over the balloon catheter, as gentle counter traction was applied to the balloon. Results Balloon-assisted guiding catheter placement was used to perform endovascular treatments of 12 anterior circulation aneurysms. One patient underwent coiling alone. Five patients underwent balloon-assisted coiling. One patient underwent balloon and stent assisted coil embolization. Four patients with five carotid aneurysms (one with bilateral carotid aneurysms) underwent vascular reconstruction with the pipeline embolization device. All patients had severe tortuosity of the extracranial carotid system. Three patients had findings consistent with cervical carotid fibromuscular dysplasia. The technique was successful each time it was attempted. No parent artery dissections or catheter induced vasospam were noted in any case. Discussion Hypercompliant balloon catheters can be reliably used

  12. Gradenigo Syndrome: Unusual Consequence of Otitis Media

    PubMed Central

    Valles, Jennie M.; Fekete, Robert

    2014-01-01

    Introduction In 1904, Giuseppe Gradenigo published his case series on the triad of ipsilateral abducens nerve palsy, facial pain in the trigeminal nerve distribution, and suppurative otitis media, which would subsequently be referred to as Gradenigo syndrome. Case Report Our patient was a 36-year-old female, 23 weeks pregnant, with a 6-day history of right-sided otalgia and hearing loss and a 4-day history of purulent otorrhea, who presented with severe, holocephalic headache, meningeal signs, fever, photophobia, and mental status decline. Lumbar puncture yielded a white blood cell count of 1,559 cells/mm3 with 95% polymorphonuclear leukocytes, a red blood cell count of 111 cells/mm3, a protein level of 61 mg/dl, and a glucose level of <40 mg/dl. Cerebrospinal fluid Gram stain showed Gram-positive diplococci, which were subsequently identified as Streptococcus pneumoniae and treated with ceftriaxone. On the second hospital day, she developed horizontal diplopia due to right abducens nerve palsy and right mydriasis. Both symptoms resolved on the third hospital day. Erosion of temporal bone and opacification of mastoid air cells was shown on CT scan. A CT venogram showed an irregularity of the left transverse and superior sagittal sinuses. She was treated with enoxaparin for possible sinus thrombosis. Discussion This case demonstrates rare but serious sequelae of otitis media and Gradenigo syndrome. Holocephalic headache from meningitis masked trigeminal pain. Involvement of the ipsilateral petrous apex and surrounding structures on imaging and clinical improvement with antibiotic treatment supports Gradenigo syndrome over intracranial hypertension due to venous sinus thrombosis as the cause of the abducens nerve palsy. PMID:25232331

  13. The cranial base of Australopithecus afarensis: new insights from the female skull.

    PubMed

    Kimbel, William H; Rak, Yoel

    2010-10-27

    Cranial base morphology differs among hominoids in ways that are usually attributed to some combination of an enlarged brain, retracted face and upright locomotion in humans. The human foramen magnum is anteriorly inclined and, with the occipital condyles, is forwardly located on a broad, short and flexed basicranium; the petrous elements are coronally rotated; the glenoid region is topographically complex; the nuchal lines are low; and the nuchal plane is horizontal. Australopithecus afarensis (3.7-3.0 Ma) is the earliest known species of the australopith grade in which the adult cranial base can be assessed comprehensively. This region of the adult skull was known from fragments in the 1970s, but renewed fieldwork beginning in the 1990s at the Hadar site, Ethiopia (3.4-3.0 Ma), recovered two nearly complete crania and major portions of a third, each associated with a mandible. These new specimens confirm that in small-brained, bipedal Australopithecus the foramen magnum and occipital condyles were anteriorly sited, as in humans, but without the foramen's forward inclination. In the large male A.L. 444-2 this is associated with a short basal axis, a bilateral expansion of the base, and an inferiorly rotated, flexed occipital squama--all derived characters shared by later australopiths and humans. However, in A.L. 822-1 (a female) a more primitive morphology is present: although the foramen and condyles reside anteriorly on a short base, the nuchal lines are very high, the nuchal plane is very steep, and the base is as relatively narrow centrally. A.L. 822-1 illuminates fragmentary specimens in the 1970s Hadar collection that hint at aspects of this primitive suite, suggesting that it is a common pattern in the A. afarensis hypodigm. We explore the implications of these specimens for sexual dimorphism and evolutionary scenarios of functional integration in the hominin cranial base.

  14. Pneumatization of the sphenoid sinus in Chinese: the differences from Caucasian and its application in the extended transsphenoidal approach.

    PubMed

    Lu, Yuntao; Pan, Jun; Qi, Songtao; Shi, Jin; Zhang, Xi'an; Wu, Kuncheng

    2011-08-01

    In recent years, the transsphenoidal approach has been extensively used surgically to treat parasellar, suprasellar, clival, and even petrous lesions. Extended pneumatization of the sphenoid sinus (SS) is considered an indispensable element for the extended transsphenoidal (ETS) approach. Because most anatomical studies of the ETS approach use Caucasian subjects, the present study aims to clarify the pneumatic extension types in Chinese individuals as well as any differences from those in Caucasians and analyze these differences with respect to the application of the ETS approach. A total of 200 computed tomography (CT) images of SSs and 18 adult cadaveric heads were selected for observation and measurement. The conchal, presellar, and sellar types comprised 6, 28.5, and 65.5% of subjects, respectively; according to the extra extension, the prevalence of the lateral, clival, lesser wing, and combined extension sinus types was 11.4, 21.4, 0.8, and 48.1% of subjects, respectively. The percentages of pneumatization of the anterior and posterior clinoid processes, pterygoid process, and optic strut were 5.0, 1.0, 22.3, and 7.0%, respectively. Onodi cells were observed in 61.1% of the sides of the cadaveric heads, including 30.6% with good pneumatization with identifiable optical or ICA bulges. These features were related to poor lateral and clival gasification in Chinese compared with Caucasians, which might make extended surgery more dangerous. However, the anterior pneumatization, especially the higher presentation of Onodi cells, ensures that the anterior ETS approach can be performed safely in Chinese patients. In general, measurements showing smaller sinus volumes and thicker bones with identifiable bone landmarks that are hard to find compared with those in Caucasians suggest increased surgical risks in the Chinese population. In this situation, carefully analysis of presurgical CT and magnetic resonance imaging scans is important. Furthermore, in the ETS

  15. CT Scan of Thirteen Natural Mummies Dating Back to the XVI-XVIII Centuries: An Emerging Tool to Investigate Living Conditions and Diseases in History

    PubMed Central

    Petrella, Enrico; Piciucchi, Sara; Feletti, Francesco; Barone, Domenico; Piraccini, Antonella; Minghetti, Caterina; Gruppioni, Giorgio; Poletti, Venerino; Bertocco, Mauro; Traversari, Mirko

    2016-01-01

    Objectives To correlate the radiologic findings detected with computed tomography scan with anthropological data in 13 naturally mummified bodies discovered during works of recovery of an ancient church in a crypt in Roccapelago, in the Italian Apennines. Methods From a group of about sixty not-intentionally mummified bodies, thirteen were selected to be investigated with volumetric computed tomography (CT). Once CT scan was performed, axial images were processed to gather MPR and Volume Rendering reconstructions. Elaborations of these images provided anthropometric measurements and a non-invasive analysis of the residual anatomical structures. For each body the grade of preservation and the eventual pathological changes were recorded. Furthermore, in order to identify nutritional and occupational markers, radiologic signs of bone tropism and degenerative changes were analysed and graded. Results Mummies included seven females and six males, with an estimated age ranging from 20 to 60 years. The first relevant finding identified was a general low grade of preservation, due to the lack of anatomic tissues different from bones, tendons and dehydrated skin. The low grade of preservation was related to the natural process of mummification. Analysing bone degenerative changes on CT scan, the majority of the bodies had significant occupational markers consisting of arthritis in the spine, lower limbs and shoulders even in young age. Few were the pathological findings identified. Among these, the most relevant included a severe bilateral congenital hip dysplasia and a wide osteolytic lesion involving left orbit and petrous bone that was likely the cause of death. Conclusions Although the low grade of preservation of these mummies, the multidisciplinary approach of anthropologists and radiologists allowed several important advances in knowledge for the epidemiology of Roccapelago. First of all, a profile of living conditions was delineated. It included occupational and

  16. Pathological Location of Cranial Nerves in Petroclival Lesions: How to Avoid Their Injury during Anterior Petrosal Approach

    PubMed Central

    Borghei-Razavi, Hamid; Tomio, Ryosuke; Fereshtehnejad, Seyed-Mohammad; Shibao, Shunsuke; Schick, Uta; Toda, Masahiro; Yoshida, Kazunari; Kawase, Takeshi

    2015-01-01

    Objectives Numerous surgical approaches have been developed to access the petroclival region. The Kawase approach, through the middle fossa, is a well-described option for addressing cranial base lesions of the petroclival region. Our aim was to gather data about the variation of cranial nerve locations in diverse petroclival pathologies and clarify the most common pathologic variations confirmed during the anterior petrosal approach. Method A retrospective analysis was made of both videos and operative and histologic records of 40 petroclival tumors from January 2009 to September 2013 in which the Kawase approach was used. The anatomical variations of cranial nerves IV–VI related to the tumor were divided into several location categories: superior lateral (SL), inferior lateral (IL), superior medial (SM), inferior medial (IM), and encased (E). These data were then analyzed taking into consideration pathologic subgroups of meningioma, epidermoid, and schwannoma. Results In 41% of meningiomas, the trigeminal nerve is encased by the tumor. In 38% of the meningiomas, the trigeminal nerve is in the SL part of the tumor, and it is in 20% of the IL portion of the tumor. In 38% of the meningiomas, the trochlear nerve is encased by the tumor. The abducens nerve is not always visible (35%). The pathologic nerve pattern differs from that of meningiomas for epidermoid and trigeminal schwannomas. Conclusion The pattern of cranial nerves IV–VI is linked to the type of petroclival tumor. In a meningioma, tumor origin (cavernous, upper clival, tentorial, and petrous apex) is the most important predictor of the location of cranial nerves IV–VI. Classification of four subtypes of petroclival meningiomas using magnetic resonance imaging is very useful to predict the location of deviated cranial nerves IV–VI intraoperatively. PMID:28035290

  17. [Computed tomography and magnetic resonance imaging of congenital abnormalities of the temporal bone].

    PubMed

    Czerny, C; Gstöttner, W; Imhof, H

    2003-03-01

    Congenital abnormalities of the temporal bone are mostly accompanied by conductive or sensori-neural hearing loss. Before any therapeutic procedures are done high resolution CT (HRCT) and magnetic resonance imaging (MRI) should be performed to establish the correct diagnosis and to plan the potentially surgical intervention. HRCT best depicts osseous changes especially those of the external auditory canal and the middle ear containing the ossicles and the osseous structures of the temporal bone and the petrous bone containing the inner ear. MRI excellently shows soft tissue changes of the inner ear especially on the high resolution 3DT2-weighted sequences which give a superb contrast between the nerves and the cerebro-spinal fluid. Malformations of the external auditory canal consists of aplasia or hypoplasia and those of the middle ear range form extreme hypoplasia or aplasia to very mild deformations of the ossicles. Malformations of the inner ear also range form complete aplasia to very mild hypoplasia of the organs of the inner ear as well as malformations concerning the nerves in the internal auditory canal range from aplasia to hypoplasia. Malformations of the temporal bone can either occur isolated or in combination in which malformations of the external and middle ear may be accompanied by those of the inner ear. Furthermore, malformations of the temporal bone may also occur in otofacial, otocervical or otoskeletal syndromes. These syndromes may be accompanied by certain malformations of the temporal bone. HRCT and MRI are both excellent methods to depict congenital abnormalities of the temporal bone and of the inner ear and should be used as complementary methods because HRCT best depicts osseous changes and MRI superbly depicts soft tissue changes. Both methods are important to establish the correct diagnosis to plan the therapeutic procedures.

  18. Epidural application of ionomeric cement implants. Experimental and clinical results.

    PubMed

    Geyer, G; Baier, G; Helms, J

    1998-04-01

    During setting and hardening, the hybrid bone substitute ionomeric cement (Ionocem) achieves a stable and durable bond with the apatite of the adjacent bone without interpository soft tissue. Fluid contact during setting results in the release of aluminium ions which may reach critical levels as high as 3000 micrograms/l. On epidural application it is, therefore, essential to prevent cement constituents from gaining access to the intradural space. After the cement has hardened, the presence of aluminium is demonstrable in the adjacent bone to a maximum depth of 20 microns (EDX microanalysis). In rabbits, epidural placement of freshly mixed cement causes slight thickening of the dura. There is reason to believe that human dura, with a thickness 10 times greater, is impermeable to components of the cement. After epidural application of the freshly mixed cement in the frontobasal and laterobasal regions and at the skull cap and petrous apex, 76 patients in all have been followed for up to 6.5 years. During this period no complications have arisen and functional (and cosmetic) results are promising. The availability of preformed implants (Ionoroc, Ionocast) permitted the peridural placement of minimal quantities of freshly mixed cement. These implants were fixed to localized sites on the adjacent calvarial bone by use of Ionocem. Notwithstanding the stringent manufacturer guidelines, there have been reports in the literature that during the vulnerable stage of setting neurotoxic aluminium ions were released into the dural space with a fatal outcome in two cases. In view of potential intradural complications, such as may occur in case of dural leaks, it was considered that further application of the material adjacent to the dura was no longer warranted. The production of Ionocem was discontinued in May 1995.

  19. Role of skeletal muscle in ear development.

    PubMed

    Rot, Irena; Baguma-Nibasheka, Mark; Costain, Willard J; Hong, Paul; Tafra, Robert; Mardesic-Brakus, Snjezana; Mrduljas-Djujic, Natasa; Saraga-Babic, Mirna; Kablar, Boris

    2017-03-08

    The current paper is a continuation of our work described in Rot and Kablar, 2010. Here, we show lists of 10 up- and 87 down-regulated genes obtained by a cDNA microarray analysis that compared developing Myf5-/-:Myod-/- (and Mrf4-/-) petrous part of the temporal bone, containing middle and inner ear, to the control, at embryonic day 18.5. Myf5-/-:Myod-/- fetuses entirely lack skeletal myoblasts and muscles. They are unable to move their head, which interferes with the perception of angular acceleration. Previously, we showed that the inner ear areas most affected in Myf5-/-:Myod-/- fetuses were the vestibular cristae ampullaris, sensitive to angular acceleration. Our finding that the type I hair cells were absent in the mutants' cristae was further used here to identify a profile of genes specific to the lacking cell type. Microarrays followed by a detailed consultation of web-accessible mouse databases allowed us to identify 6 candidate genes with a possible role in the development of the inner ear sensory organs: Actc1, Pgam2, Ldb3, Eno3, Hspb7 and Smpx. Additionally, we searched for human homologues of the candidate genes since a number of syndromes in humans have associated inner ear abnormalities. Mutations in one of our candidate genes, Smpx, have been reported as the cause of X-linked deafness in humans. Our current study suggests an epigenetic role that mechanical, and potentially other, stimuli originating from muscle, play in organogenesis, and offers an approach to finding novel genes responsible for altered inner ear phenotypes.

  20. Carotid and cranial nerve reconstruction after removal of cavernous sinus lesions.

    PubMed

    Sekhar, L N; Sen, C N; Lanzino, G; Pomonis, S

    1991-12-01

    During the last 7 years, approximately 170 neoplasms, and 35 vascular lesions involving the cavernous sinus were treated by the first two authors. During the treatment of such lesions, the direct vein graft reconstruction of the internal carotid artery from the petrous to the supraclinoid or infraclinoid ICA was performed in 23 patients. Graft occlusion occurred in 3 patients and in one of these, it was successfully salvaged by placing a long venous graft from the extracranial ICA to the M3 segment of the middle cerebral artery. The latter 3 patients were neurologically normal. One patient with significant atherosclerotic disease suffered the dissection of the distal internal carotid artery with the graft being patent. The suturing technique. This patient eventually died. Two patients with severely compromised collateral circulation suffered minor strokes due to the temporary occlusion of the ICA. This has been avoided in the more recent patients by the adoption of brain protection techniques such as moderate hypothermia, induced hypertension, and barbiturate coma. Low dose heparin therapy during grafting and high dose intravenous steroids prior to the grafting also appear to be beneficial. Direct vein graft reconstruction of the intracavernous carotid artery is a valuable tool during the management of cavernous sinus lesions. The advantages and disadvantages of this technique as well as the pros and cons of other revascularization techniques will be discussed. During microsurgical removal of cavernous sinus lesions, the cranial nerves III-VI were reconstructed by direct resuture or by nerve grafting in 16 patients. In the majority of these patients, recovery of cranial nerve function was observed, which was very encouraging.(ABSTRACT TRUNCATED AT 250 WORDS)

  1. Percutaneous transluminal angioplasty for atherosclerotic stenosis of the intracranial cerebral arteries. initial results and long-term follow-up.

    PubMed

    Hyodo, A; Kato, N; Nakai, Y; Anno, I; Sato, H; Okazaki, M; Matsumaru, Y; Nose, T

    1999-11-01

    Percutaneous transluminal angioplasty (PTA) was carried out 52 times for 49 lesions in 47 cases of atheroscrelotic stenosis of the intracranial or skull base cerebral arteries. The stenotic lesions involved the middle cerebral artery in 21 cases, the basilar artery in eight cases, the internal carotid artery (petrous-supraclinoid portion) in 15 cases, and the intracranial vertebral artery in five cases. Nearly all cases were symptomatic, such as TIA or stroke, and the degree of stenosis ranged from 70 to 99 percent, with a mean of 80 percent. PTA was performed using a STEALTH balloon angioplasty catheter. In these trials, PTA was successfully performed (as indicated by a residual stenosis under 50%) 41 times. The initial success rate was 79% and stenosis was reduced from 80% to 25%. Clinical follow-up was performed from 7 to 84 months with a mean of 44 months. During this period, death due to myocardial infarction or pneumonia occurred in five cases, stroke related to previous PTA occurred ih one case (due to re-stenosis) and stroke unrelated tl? previous PTA occurred in two cases. Angiographic follow-up was performed in 31 cases after 41 successful PTA procedures. Re-stenosis was seen in 20% of the cases, symptomrltic complications occurred in 6%, and asymptomatic complications occurred in 6% of the cases. One case suffered severe subarachnoid hemorrhage just after the PTA due to preexisting aneurysm rupture and he died a week after the PTA. So mortality in this series was 2%. From the results described here, we may conclude that PTA of the intracranial or skull base cerebral artery is technically feasible, and it can be performed with relatively low risk. From our results, it may be a useful method and effective for long-term survival of patients. But results from a larger number of patients and more long-term follow-up data are still necessary in order to evaluate the safety and usefulness of this method.

  2. Operative management of tumors involving the cavernous sinus.

    PubMed

    Sekhar, L N; Møller, A R

    1986-06-01

    In the past, neurosurgeons have been reluctant to operate on tumors involving the cavernous sinus because of the possibility of bleeding from the venous plexus or injury to the internal carotid artery (ICA) or the third, fourth, or sixth cranial nerves. The authors describe techniques for a more aggressive surgical approach to neoplasms in this area that are either benign or locally confined malignant lesions. During the last 2 years, seven tumors involving the cavernous sinus have been resected: six totally and one subtotally. The preoperative evaluation included axial and coronal computerized tomography, cerebral angiography, and a balloon-occlusion test of the ICA. Intraoperative monitoring of the third, fourth, sixth, and seventh cranial nerves was used to assist in locating the nerves and in avoiding injury to them. The first major step in the operative procedure was to obtain proximal control of the ICA at the petrous apex and distal control in the supraclinoid segment. The cavernous sinus was then opened by a lateral, superior, or inferior approach for tumor resection. Temporary clipping and suture of the ICA was necessary in one patient. None of the patients died or suffered a stroke postoperatively. Permanent trigeminal nerve injury occurred in three patients; in two, this was the result of tumor invasion. One patient suffered temporary paralysis of the third, fourth, and sixth cranial nerves, and in another the sixth cranial nerve was temporarily paralyzed. Preoperative cranial nerve deficits were improved postoperatively in three patients. Radiation therapy was administered postoperatively to four patients. These seven patients have been followed for 6 to 18 months to date and none has shown evidence of recurrence of the intracavernous tumor.

  3. Percutaneous transluminal angioplasty and stenting for severe stenosis of the intracranial extradural internal carotid artery causing transient ischemic attack or minor stroke

    PubMed Central

    Ko, Jun Kyeung; Choi, Chang Hwa; Cha, Seung Heon; Choi, Byung Kwan; Cho, Won Ho; Kang, Tae Ho; Sung, Sang Min; Cho, Han Jin

    2015-01-01

    The purpose of this study is to assess the technical feasibility and clinical efficacy of percutaneous transluminal angioplasty and stenting (PTAS) for symptomatic stenosis of the intracranial extradural (petrous and cavernous) internal carotid artery (ICA). Review of medical records identified 26 consecutive patients who underwent PTAS using a balloon-expandable coronary stent (n = 15, 57.7%) or a Wingspan self-expandable stent (n = 11, 42.3%) for treatment of severe stenosis (>70%) involving the intracranial extradural ICA. The inclusion criteria were transient ischemic attack with an ABCD2 score of ≥3 (n = 12, 46.2%) or minor stroke with an NIHSS score of ≤4 (n = 14, 53.8%). Technical success rates, complications, and angiographic and clinical outcomes were analyzed retrospectively. PTAS was technically successful in all patients. The mean stenosis ratio decreased from 77.1% to 10.0% immediately after PTAS. The overall incidence of procedural complications was 23.1%, and the postoperative permanent morbidity/mortality rate was 7.7%. A total of 22 patients were tracked over an average period of 29.9 months. During the observation period, 20 patients (90.9%) had no further cerebrovascular events and stroke recurrence occurred in two patients (9.1%), resulting in an annual stroke risk of 3.7%. Two cases (11.1%) of significant in-stent restenosis (>50%) were found on follow-up angiography (n = 18). PTAS for severe stenosis (>70%) involving the intracranial extradural ICA showed a good technical feasibility and favorable clinical outcome in patients with transient ischemic attack or minor stroke. PMID:26063697

  4. Cladistic analysis of extant and fossil African papionins using craniodental data.

    PubMed

    Gilbert, Christopher C

    2013-05-01

    This study examines African papionin phylogenetic history through a comprehensive cladistic analysis of extant and fossil craniodental morphology using both quantitative and qualitative characters. To account for the well-documented influence of allometry on the papionin skull, the general allometric coding method was applied to characters determined to be significantly affected by allometry. Results of the analyses suggest that Parapapio, Pliopapio, and Papio izodi are stem African papionin taxa. Crown Plio-Pleistocene African papionin taxa include Gorgopithecus, Lophocebus cf. albigena, Procercocebus, Soromandrillus (new genus defined herein) quadratirostris, and, most likely, Dinopithecus. Furthermore, S. quadratirostris is a member of a clade also containing Mandrillus, Cercocebus, and Procercocebus; ?Theropithecus baringensis is strongly supported as a primitive member of the genus Theropithecus; Gorgopithecus is closely related to Papio and Lophocebus; and Theropithecus is possibly the most primitive crown African papionin taxon. Finally, character transformation analyses identify a series of morphological transformations during the course of papionin evolution. The origin of crown African papionins is diagnosed, at least in part, by the appearance of definitive and well-developed male maxillary ridges and maxillary fossae. Among crown African papionins, Papio, Lophocebus, and Gorgopithecus are further united by the most extensive development of the maxillary fossae. The Soromandrillus/Mandrillus/Cercocebus/Procercocebus clade is diagnosed by upturned nuchal crests (especially in males), widely divergent temporal lines (especially in males), medially oriented maxillary ridges in males, medially oriented inferior petrous processes, and a tendency to enlarge the premolars as an adaptation for hard-object food processing. The adaptive origins of the genus Theropithecus appear associated with a diet requiring an increase in size of the temporalis, the optimal

  5. Pathological Location of Cranial Nerves in Petroclival Lesions: How to Avoid Their Injury during Anterior Petrosal Approach.

    PubMed

    Borghei-Razavi, Hamid; Tomio, Ryosuke; Fereshtehnejad, Seyed-Mohammad; Shibao, Shunsuke; Schick, Uta; Toda, Masahiro; Yoshida, Kazunari; Kawase, Takeshi

    2016-02-01

    Objectives Numerous surgical approaches have been developed to access the petroclival region. The Kawase approach, through the middle fossa, is a well-described option for addressing cranial base lesions of the petroclival region. Our aim was to gather data about the variation of cranial nerve locations in diverse petroclival pathologies and clarify the most common pathologic variations confirmed during the anterior petrosal approach. Method A retrospective analysis was made of both videos and operative and histologic records of 40 petroclival tumors from January 2009 to September 2013 in which the Kawase approach was used. The anatomical variations of cranial nerves IV-VI related to the tumor were divided into several location categories: superior lateral (SL), inferior lateral (IL), superior medial (SM), inferior medial (IM), and encased (E). These data were then analyzed taking into consideration pathologic subgroups of meningioma, epidermoid, and schwannoma. Results In 41% of meningiomas, the trigeminal nerve is encased by the tumor. In 38% of the meningiomas, the trigeminal nerve is in the SL part of the tumor, and it is in 20% of the IL portion of the tumor. In 38% of the meningiomas, the trochlear nerve is encased by the tumor. The abducens nerve is not always visible (35%). The pathologic nerve pattern differs from that of meningiomas for epidermoid and trigeminal schwannomas. Conclusion The pattern of cranial nerves IV-VI is linked to the type of petroclival tumor. In a meningioma, tumor origin (cavernous, upper clival, tentorial, and petrous apex) is the most important predictor of the location of cranial nerves IV-VI. Classification of four subtypes of petroclival meningiomas using magnetic resonance imaging is very useful to predict the location of deviated cranial nerves IV-VI intraoperatively.

  6. Degradation of the Bragg peak due to inhomogeneities.

    PubMed

    Urie, M; Goitein, M; Holley, W R; Chen, G T

    1986-01-01

    The rapid fall-off of dose at the end of range of heavy charged particle beams has the potential in therapeutic applications of sparing critical structures just distal to the target volume. Here we explored the effects of highly inhomogeneous regions on this desirable depth-dose characteristic. The proton depth-dose distribution behind a lucite-air interface parallel to the beam was bimodal, indicating the presence of two groups of protons with different residual ranges, creating a step-like depth-dose distribution at the end of range. The residual ranges became more spread out as the interface was angled at 3 degrees, and still more at 6 degrees, to the direction of the beam. A second experiment showed little significant effect on the distal depth-dose of protons having passed through a mosaic of teflon and lucite. Anatomic studies demonstrated significant effects of complex fine inhomogeneities on the end of range characteristics. Monoenergetic protons passing through the petrous ridges and mastoid air cells in the base of skull showed a dramatic degradation of the distal Bragg peak. In beams with spread out Bragg peaks passing through regions of the base of skull, the distal fall-off from 90 to 20% dose was increased from its nominal 6 to well over 32 mm. Heavy ions showed a corresponding degradation in their ends of range. In the worst case in the base of skull region, a monoenergetic neon beam showed a broadening of the full width at half maximum of the Bragg peak to over 15 mm (compared with 4 mm in a homogeneous unit density medium). A similar effect was found with carbon ions in the abdomen, where the full width at half maximum of the Bragg peak (nominally 5.5 mm) was found to be greater than 25 mm behind gas-soft-tissue interfaces. We address the implications of these data for dose computation with heavy charged particles.

  7. The cranial base of Australopithecus afarensis: new insights from the female skull

    PubMed Central

    Kimbel, William H.; Rak, Yoel

    2010-01-01

    Cranial base morphology differs among hominoids in ways that are usually attributed to some combination of an enlarged brain, retracted face and upright locomotion in humans. The human foramen magnum is anteriorly inclined and, with the occipital condyles, is forwardly located on a broad, short and flexed basicranium; the petrous elements are coronally rotated; the glenoid region is topographically complex; the nuchal lines are low; and the nuchal plane is horizontal. Australopithecus afarensis (3.7–3.0 Ma) is the earliest known species of the australopith grade in which the adult cranial base can be assessed comprehensively. This region of the adult skull was known from fragments in the 1970s, but renewed fieldwork beginning in the 1990s at the Hadar site, Ethiopia (3.4–3.0 Ma), recovered two nearly complete crania and major portions of a third, each associated with a mandible. These new specimens confirm that in small-brained, bipedal Australopithecus the foramen magnum and occipital condyles were anteriorly sited, as in humans, but without the foramen's forward inclination. In the large male A.L. 444-2 this is associated with a short basal axis, a bilateral expansion of the base, and an inferiorly rotated, flexed occipital squama—all derived characters shared by later australopiths and humans. However, in A.L. 822-1 (a female) a more primitive morphology is present: although the foramen and condyles reside anteriorly on a short base, the nuchal lines are very high, the nuchal plane is very steep, and the base is as relatively narrow centrally. A.L. 822-1 illuminates fragmentary specimens in the 1970s Hadar collection that hint at aspects of this primitive suite, suggesting that it is a common pattern in the A. afarensis hypodigm. We explore the implications of these specimens for sexual dimorphism and evolutionary scenarios of functional integration in the hominin cranial base. PMID:20855310

  8. Procedures for restoring vestibular disorders

    PubMed Central

    Walther, Leif Erik

    2005-01-01

    This paper will discuss therapeutic possibilities for disorders of the vestibular organs and the neurons involved, which confront ENT clinicians in everyday practice. Treatment of such disorders can be tackled either symptomatically or causally. The possible strategies for restoring the body's vestibular sense, visual function and co-ordination include medication, as well as physical and surgical procedures. Prophylactic or preventive measures are possible in some disorders which involve vertigo (bilateral vestibulopathy, kinetosis, height vertigo, vestibular disorders when diving (Tables 1 (Tab. 1) and 2 (Tab. 2)). Glucocorticoid and training therapy encourage the compensation of unilateral vestibular loss. In the case of a bilateral vestibular loss, it is important to treat the underlying disease (e.g. Cogan's disease). Although balance training does improve the patient's sense of balance, it will not restore it completely. In the case of Meniere's disease, there are a number of medications available to either treat bouts or to act as a prophylactic (e.g. dimenhydrinate or betahistine). In addition, there are non-ablative (sacculotomy) as well as ablative surgical procedures (e.g. labyrinthectomy, neurectomy of the vestibular nerve). In everyday practice, it has become common to proceed with low risk therapies initially. The physical treatment of mild postural vertigo can be carried out quickly and easily in outpatients (repositioning or liberatory maneuvers). In very rare cases it may be necessary to carry out a semicircular canal occlusion. Isolated disturbances of the otolith function or an involvement of the otolith can be found in roughly 50% of labyrinth disturbances. A specific surgical procedure to selectively block the otolith organs is currently being studied. When an external perilymph fistula involving loss of perilymph is suspected, an exploratory tympanotomy involving also the round and oval window niches must be carried out. A traumatic rupture of

  9. MS Non-Pharmacological Countermeasure to Decrease Landing Sickness and Improve Functional Performance While Disorientad

    NASA Technical Reports Server (NTRS)

    Rosenberg, M. J. F.; Kreutzberg, G. A.; Galvan-Garza, R. C.; Mulavara, A. P.; Reschke, M. F.

    2017-01-01

    Upon return from spaceflight, a majority of crewmembers experience motion sickness (MS) symptoms. The interactions between crewmembers' adaptation to a gravitational transition, the performance decrements resulting from MS and/or use of promethazine (PMZ), and the constraints imposed by mission task demands could significantly challenge and limit an astronaut's ability to perform functional tasks during gravitational transitions. No operational countermeasure currently exists to mitigate the risks associated with these sensorimotor disturbances. Stochastic resonance (SR) can be thought of simply as "noise benefit" or an increase in information transfer by a system when in the presence of a non-zero level of noise. We have shown that low levels of stochastic vestibular stimulation (SVS) improve balance and locomotor performance due to SR (Goel et al. 2015, Mulavara et al. 2011, 2015). Additionally, a study in a 6-hydroxydopamine (6-OHDA) hemi-lesioned rat model of Parkinson's disease demonstrated improvements in locomotor activity after low-level SVS delivery possibly due to an increase in nigral gamma-aminobutyric acid (GABA) release in a dopamine independent way (Samoudi et al. 2012). SVS specifically increased GABA release on the lesioned, but not the intact side. These results suggest that SVS can cause targeted alterations of GABA release to affect performance of functional tasks. Activation of the GABA pathway is important in modulating MS and promoting adaptability (Cohen 2008). Magnusson et al. (2000) supported this finding by showing that the administration of a GABAB agonist caused a reversal of the symptoms that is normally seen after unilateral labyrinthectomy. Thus, GABA could play a significant role in reducing MS and promoting adaptability. We have taken advantage of the SR mechanism as a modulator of neurotransmitters to develop a unique SVS countermeasure system to mitigate MS symptoms and improve functional performance after landing. Healthy

  10. Dopamine Modulates Motor Control in a Specific Plane Related to Support

    PubMed Central

    Herbin, Marc; Simonis, Caroline; Revéret, Lionel; Hackert, Rémi; Libourel, Paul-Antoine; Eugène, Daniel; Diaz, Jorge; de Waele, Catherine; Vidal, Pierre-Paul

    2016-01-01

    At the acute stage following unilateral labyrinthectomy (UL), rats, mice or guinea pigs exhibit a complex motor syndrome combining circling (HSCC lesion) and rolling (utricular lesion). At the chronic stage, they only display circling, because proprioceptive information related to the plane of support substitutes the missing utricular information to control posture in the frontal plane. Circling is also observed following unilateral lesion of the mesencephalic dopaminergic neurons by 6- hydroxydopamine hydrobromide (6-OHDA rats) and systemic injection of apomorphine (APO rats). The resemblance of behavior induced by unilateral vestibular and dopaminergic lesions at the chronic stage can be interpreted in two ways. One hypothesis is that the dopaminergic system exerts three-dimensional control over motricity, as the vestibular system does. If this hypothesis is correct, then a unilateral lesion of the nigro-striatal pathway should induce three-dimensional motor deficits, i.e., circling and at least some sort of barrel rolling at the acute stage of the lesion. Then, compensation could also take place very rapidly based on proprioception, which would explain the prevalence of circling. In addition, barrel rolling should reappear when the rodent is placed in water, as it occurs in UL vertebrates. Alternatively, the dopaminergic network, together with neurons processing the horizontal canal information, could control the homeostasis of posture and locomotion specifically in one and only one plane of space, i.e. the plane related to the basis of support. In that case, barrel rolling should never occur, whether at the acute or chronic stage on firm ground or in water. Moreover, circling should have the same characteristics following both types of lesions. Clearly, 6-OHDA and APO-rats never exhibited barrel rolling at the acute stage. They circled at the acute stage of the lesion and continued to do so three weeks later, including in water. In contrast, UL-rats, exhibited

  11. [Squirrel monkey--an ideal primate (correction of prmate) model of space physiology].

    PubMed

    Matsunami, K

    1997-06-01

    to elucidate functions of the peripheral vestibular system. A transfer function was proposed to explain the behaviors of regular and irregular unit activity of vestibular nerve fibers. The physiologic characteristics of the second order vestibular neuron was investigated in combination of electrophysiological and micro-morphological way, with using WGA-HRP methods, in relation to somato-motor and eye movements. Interconnections between vestibular neurons and cerebellum, interstitial nucleus of Cajal, oculomotor nuclear complex, superior colliculus and cervical spinal cord were elucidated. In physiological field of the vestibular system, the vestibulo-ocular reflex is well studied and results obtained from the squirrel monkey experiments were reviewed. The squirrel monkey, particularly the Bolivian, is a unique animal in that it is vulnerable to motion sickness induced by visual-motion stimulation with phase mismatch of the two stimuli. Experimental results of labyrinthectomy or bilateral ablation of the maculae staticae led to the conclusion that both semicircular and otolith organs are involved in the genesis of space motion sickness. On the other hand, destruction of the area postrema, acknowledged as the vomiting center to chemical stimulants, produced controversial results. However, it must be pointed out that the a human subject underwent to resection of the area postrema, became insensitive to administration of apomorphine, a well known chemical stimulant of vomiting. Finally the experiments in space revealed the presence of at least two origins of caloric nystagmus, that is, attributable to convection and non-convection current of the endolymphatic fluid.

  12. Adaptive Changes In Postural Equilibrium And Motion Sickness Following Repeated Exposures To Virtual Environments

    NASA Technical Reports Server (NTRS)

    Harm, D. L.; Taylor, L. C.

    2006-01-01

    Virtual environments offer unique training opportunities, particularly for training astronauts and preadapting them to the novel sensory conditions of microgravity. Two unresolved human factors issues in virtual reality (VR) systems are: 1) potential "cybersickness", and 2) maladaptive sensorimotor performance following exposure to VR systems. Interestingly, these aftereffects are often quite similar to adaptive sensorimotor responses observed in astronauts during and/or following space flight. Changes in the environmental sensory stimulus conditions and the way we interact with the new stimuli may result in motion sickness, and perceptual, spatial orientation and sensorimotor disturbances. Initial interpretation of novel sensory information may be inappropriate and result in perceptual errors. Active exploratory behavior in a new environment, with resulting feedback and the formation of new associations between sensory inputs and response outputs, promotes appropriate perception and motor control in the new environment. Thus, people adapt to consistent, sustained alterations of sensory input such as those produced by microgravity, unilateral labyrinthectomy and experimentally produced stimulus rearrangements. Adaptation is revealed by aftereffects including perceptual disturbances and sensorimotor control disturbances. The purpose of the current study was to compare disturbances in postural control produced by dome and head-mounted virtual environment displays, and to examine the effects of exposure duration, and repeated exposures to VR systems. Forty-one subjects (21 men, 20 women) participated in the study with an age range of 21-49 years old. One training session was completed in order to achieve stable performance on the posture and VR tasks before participating in the experimental sessions. Three experimental sessions were performed each separated by one day. The subjects performed a navigation and pick and place task in either a dome or head-mounted display

  13. Distinctive patterns on CT angiography characterize acute internal carotid artery occlusion subtypes

    PubMed Central

    Hong, Ji Man; Lee, Sung Eun; Lee, Seong-Joon; Lee, Jin Soo; Demchuk, Andrew M.

    2017-01-01

    Abstract Noninvasive computed tomography angiography (CTA) is widely used in acute ischemic stroke, even for diagnosing various internal carotid artery (ICA) occlusion sites, which often need cerebral digital subtraction angiography (DSA) confirmation. We evaluated whether clinical outcomes vary depending on the DSA-based occlusion sites and explored correlating features on baseline CTA that predict DSA-based occlusion site. We analyzed consecutive patients with acute ICA occlusion who underwent DSA and CTA. Occlusion site was classified into cervical, cavernous, petrous, and carotid terminus segments by DSA confirmation. Clinical and radiological features associated with poor outcome at 3 months (3–6 of modified Rankin scale) were analyzed. Baseline CTA findings were categorized according to carotid occlusive shape (stump, spearhead, and streak), presence of cervical calcification, Willisian occlusive patterns (T-type, L-type, and I-type), and status of leptomeningeal collaterals (LMC). We identified 49 patients with occlusions in the cervical (n = 17), cavernous (n = 22), and carotid terminus (n = 10) portions: initial NIH Stroke Scale (11.4 ± 4.2 vs 16.1 ± 3.7 vs 18.2 ± 5.1; P < 0.001), stroke volume (27.9 ± 29.6 vs 127.4 ± 112.6 vs 260.3 ± 151.8 mL; P < 0.001), and poor outcome (23.5 vs 77.3 vs 90.0%; P < 0.001). Cervical portion occlusion was characterized as rounded stump (82.4%) with calcification (52.9%) and fair LMC (94.1%); cavernous as spearhead occlusion (68.2%) with fair LMC (86.3%) and no calcification (95.5%); and terminus as streak-like occlusive pattern (60.0%) with poor LMC (60.0%), and no calcification (100%) on CTA. Our study indicates that acute ICA occlusion can be subtyped into cervical, cavernous, and terminus. Distinctive findings on initial CTA can help differentiate ICA-occlusion subtypes with specific characteristics. PMID:28151850

  14. A comparison of concentrations of lead in human tissues.

    PubMed Central

    Barry, P S

    1975-01-01

    This postmortem study of lead concentrations in the tissues of 129 subjects is an extension to a report by Barry and Mossman (1970). Lead concentrations in bone greatly exceeded the concentrations in soft tissues and were highest in the dense bones. Bone lead concentrations increased with age in both sexes, more especially in male subjects and in dense bone, varying between mean values of 2-16 ppm in the ribs of children to over 50 ppm in the dense petrous temporal bones of elderly male adults. Male adults contained over 30% more lead in their bones than females. Mean concentrations of lead in the soft tissues varied from less than 0-1 ppm in organs such as muscle and heart to over 2 ppm in the aorta. In most tissues with lead values in excess of 0-2 ppm the male concentrations exceeded female values by about 30%. With the exception of the aorta, spleen, lung, and prostate, lead concentrations did not increase with age in the soft tissues of either sex after about the second decade of life. Children showed concentrations of lead in their soft tissues comparable to female adults, but the concentrations in bone were much lower. It is suggested that children do not possess the same capacity as adults to retain lead in bone. In male adults occupationally exposed to lead the concentrations of lead in bone exceeded the concentrations in unexposed male adults within the same age group by two-to three-fold. Soft tissue lead concentrations between the two groups were less divergent. An assessment of the total body burden of lead revealed higher levels in adult male subjects than in females at mean values of 164-8 mg compared to 103-6 mg, respectively. Over 90% of the total body burden of lead in adults was in bone, of which over 70% was in dense bone. Male adults occupationally exposed to lead had mean total body burdens of 566-4 mg Pb, of which 97% was in bone. The release of lead from bone in conjunction with calcium was not considered to be of physiological significance

  15. Proposed clinical internal carotid artery classification system

    PubMed Central

    Abdulrauf, Saleem I; Ashour, Ahmed M; Marvin, Eric; Coppens, Jeroen; Kang, Brian; Hsieh, Tze Yu Yeh; Nery, Breno; Penanes, Juan R; Alsahlawi, Aysha K; Moore, Shawn; Al-Shaar, Hussam Abou; Kemp, Joanna; Chawla, Kanika; Sujijantarat, Nanthiya; Najeeb, Alaa; Parkar, Nadeem; Shetty, Vilaas; Vafaie, Tina; Antisdel, Jastin; Mikulec, Tony A; Edgell, Randall; Lebovitz, Jonathan; Pierson, Matt; Pires de Aguiar, Paulo Henrique; Buchanan, Paula; Di Cosola, Angela; Stevens, George

    2016-01-01

    Introduction: Numerical classification systems for the internal carotid artery (ICA) are available, but modifications have added confusion to the numerical systems. Furthermore, previous classifications may not be applicable uniformly to microsurgical and endoscopic procedures. The purpose of this study was to develop a clinically useful classification system. Materials and Methods: We performed cadaver dissections of the ICA in 5 heads (10 sides) and evaluated 648 internal carotid arteries with computed tomography angiography. We identified specific anatomic landmarks to define the beginning and end of each ICA segment. Results: The ICA was classified into eight segments based on the cadaver and imaging findings: (1) Cervical segment; (2) cochlear segment (ascending segment of the ICA in the temporal bone) (relation of the start of this segment to the base of the styloid process: Above, 425 sides [80%]; below, 2 sides [0.4%]; at same level, 107 sides [20%]; P < 0.0001) (relation of cochlea to ICA: Posterior, 501 sides [85%]; posteromedial, 84 sides [14%]; P < 0.0001); (3) petrous segment (horizontal segment of ICA in the temporal bone) starting at the crossing of the eustachian tube superolateral to the ICA turn in all 10 samples; (4) Gasserian-Clival segment (ascending segment of ICA in the cavernous sinus) starting at the petrolingual ligament (PLL) (relation to vidian canal on imaging: At same level, 360 sides [63%]; below, 154 sides [27%]; above, 53 sides [9%]; P < 0.0001); in this segment, the ICA projected medially toward the clivus in 275 sides (52%) or parallel to the clivus with no deviation in 256 sides (48%; P < 0.0001); (5) sellar segment (medial loop of ICA in the cavernous sinus) starting at the takeoff of the meningeal hypophyseal trunk (ICA was medial into the sella in 271 cases [46%], lateral without touching the sella in 127 cases [23%], and abutting the sella in 182 cases [31%]; P < 0.0001); (6) sphenoid segment (lateral loop of ICA within the

  16. Hereditary deafness and phenotyping in humans.

    PubMed

    Bitner-Glindzicz, Maria

    2002-01-01

    Hereditary deafness has proved to be extremely heterogeneous genetically with more than 40 genes mapped or cloned for non-syndromic dominant deafness and 30 for autosomal recessive non-syndromic deafness. In spite of significant advances in the understanding of the molecular basis of hearing loss, identifying the precise genetic cause in an individual remains difficult. Consequently, it is important to exclude syndromic causes of deafness by clinical and special investigation and to use all available phenotypic clues for diagnosis. A clinical approach to the aetiological investigation of individuals with hearing loss is suggested, which includes ophthalmology review, renal ultrasound scan and neuro-imaging of petrous temporal bone. Molecular screening of the GJB2 (Connexin 26) gene should be undertaken in all cases of non-syndromic deafness where the cause cannot be identified, since it is a common cause of recessive hearing impairment, the screening is straightforward, and the phenotype unremarkable. By the same token, mitochondrial inheritance of hearing loss should be considered in all multigeneration families, particularly if there is a history of exposure to aminoglycoside antibiotics, since genetic testing of specific mitochondrial genes is technically feasible. Most forms of non-syndromic autosomal recessive hearing impairment cause a prelingual hearing loss, which is generally severe to profound and not associated with abnormal radiology. Exceptions to this include DFNB2 (MYO7A), DFNB8/10 (TMPRSS3) and DFNB16 (STRC) where age of onset may sometimes be later on in childhood, DFNB4 (SLC26A4) where there may be dilated vestibular aqueducts and endolymphatic sacs, and DFNB9 (OTOF) where there may also be an associated auditory neuropathy. Unusual phenotypes in autosomal dominant forms of deafness, include low frequency hearing loss in DFNA1 (HDIA1) and DFNA6/14/38 (WFS1), mid-frequency hearing loss in DFNA8/12 (TECTA), DFNA13 (COL11A2) and vestibular symptoms

  17. Magnetic resonance imaging of the inner ear by using a hybrid radiofrequency coil at 7 T

    NASA Astrophysics Data System (ADS)

    Kim, Kyoung-Nam; Heo, Phil; Kim, Young-Bo; Han, Gyu-Cheol

    2015-01-01

    Visualization of the membranous structures of the inner ear has been limited to the detection of the normal fluid signal intensity within the bony labyrinth by using magnetic resonance imaging (MRI) equipped with a 1.5 Tesla (T) magnet. High-field (HF) MRI has been available for more than a decade, and numerous studies have documented its significant advantages over conventional MRI with regards to its use in basic scientific research and routine clinical assessments. No previous studies of the inner ear by using HF MRI have been reported, in part because high-quality resolution of mastoid pneumatization is challenging due to artifacts generated in the HF environment and insufficient performance of radiofrequency (RF) coils. Therefore, a hybrid RF coil with integrated circuitry was developed at 7 T and was targeted for anatomical imaging to achieve a high resolution image of the structure of the human inner ear, excluding the bony portion. The inner-ear's structure is composed of soft tissues containing hydrogen ions and includes the membranous labyrinth, endolymphatic space, perilymphatic space, and cochlear-vestibular nerves. Visualization of the inner-ear's anatomy was performed in-vivo with a custom-designed hybrid RF coil and a specific imaging protocol based on an interpolated breath-held examination sequence. The comparative signal intensity value at 30-mm away from the phantom side was 88% higher for the hybrid RF coil and 24% higher for the 8-channel transmit/receive (Tx/Rx) coil than for the commercial birdcage coil. The optimized MRI protocol employed a hybrid RF coil because it enabled high-resolution imaging of the inner-ear's anatomy and accurate mapping of structures including the cochlea and the semicircular canals. These results indicate that 7 T MRI achieves high spatial resolution visualization of the inner-ear's anatomy. Therefore, MRI imaging using a hybrid RF coil at 7 T could provide a powerful tool for clinical investigations of petrous

  18. [Paratrigeminal epidermoid originated in the meckel's cave (author's transl)].

    PubMed

    Miyasaka, Y; Morii, S; Tachibana, S; Saito, T; Ohwada, T

    1976-05-01

    We have reported a case of paratrigeminal epidermoid originated in the Meckel's cave. A 30 years old man was admitted to the department of neurosurgery with chief complaints of continuous right facial pain and numbness of entire right side of the face of three years duration. The positive neurological findings were hypesthesia over the distribution of the right trigeminal nerve, absence of the right corneal reflex and nystagmus on left lateral gaze. Caloric response was absent on the right side, however the audiogram showed normal. Cerebrospinal fluid examination was within normal limit. Electromyography showed giant spike in the right masseter and temporal muscles. Radiogram of the skull revealed a bone-destroying lesion over the medial florr of the right middle fossa involving the apex of the petrous bone (Fig 1). Right carotid angiography showed straightening and forward displacement of C4- C5 portion of the carotid siphon in the lateral view, and vertebral angiography showed displacement of basilar artery to the left side, upward displacement of the right posterior cerebral and superior cerebellar artery in the frontal view (Fig. 2, 3). At the time of operation, an epidermoid was identified in the Meckel's cave and totally removed microsurgically. Small amount of the tumor extending into the posterior fossa was also removed (Fig. 4, 5, 6, 7). Postoperative course was uneventfull except for an episode of headache and high fever of short duration, suggesting the signs of meningial irritation. Two months postoperativelly patient was relived of facial pain and was discharged with sensory impairment of the right trigeminal nerve distribution. Only 11 cases of paratrigeminal epidermoid, including the cases localized in the Meckel's cave have been reported in the past literatures (Table 1). In this paper we have discussed about the symptomatology and clinical data of paratrigeminal epidermoid and compared with those of trigeminal neurinoma, and meningioma originated

  19. Adaptive Changes In Postural Equilibrium And Motion Sickness Following Repeated Exposures To Virtual Environments

    NASA Technical Reports Server (NTRS)

    Harm, D. L.; Taylor, L. C.

    2006-01-01

    Virtual environments offer unique training opportunities, particularly for training astronauts and preadapting them to the novel sensory conditions of microgravity. Two unresolved human factors issues in virtual reality (VR) systems are: 1) potential "cybersickness", and 2) maladaptive sensorimotor performance following exposure to VR systems. Interestingly, these aftereffects are often quite similar to adaptive sensorimotor responses observed in astronauts during and/or following space flight. Changes in the environmental sensory stimulus conditions and the way we interact with the new stimuli may result in motion sickness, and perceptual, spatial orientation and sensorimotor disturbances. Initial interpretation of novel sensory information may be inappropriate and result in perceptual errors. Active exploratory behavior in a new environment, with resulting feedback and the formation of new associations between sensory inputs and response outputs, promotes appropriate perception and motor control in the new environment. Thus, people adapt to consistent, sustained alterations of sensory input such as those produced by microgravity, unilateral labyrinthectomy and experimentally produced stimulus rearrangements. Adaptation is revealed by aftereffects including perceptual disturbances and sensorimotor control disturbances. The purpose of the current study was to compare disturbances in postural control produced by dome and head-mounted virtual environment displays, and to examine the effects of exposure duration, and repeated exposures to VR systems. Forty-one subjects (21 men, 20 women) participated in the study with an age range of 21-49 years old. One training session was completed in order to achieve stable performance on the posture and VR tasks before participating in the experimental sessions. Three experimental sessions were performed each separated by one day. The subjects performed a navigation and pick and place task in either a dome or head-mounted display

  20. Semicircular canals and agility: the influence of size and shape measures

    PubMed Central

    Cox, Philip G; Jeffery, Nathan

    2010-01-01

    The semicircular canals of the inner ear sense angular accelerations and decelerations of the head and enable co-ordination of posture and body movement, as well as visual stability. Differences of agility and spatial sensitivity among species have been linked to interspecific differences in the relative size of the canals, particularly the radius of curvature (R) and the ratio of the canal plane area to streamline length (P/L). Here we investigate the scaling relationships of these two size variables and also out-of-plane torsion in the three semicircular canals (anterior, posterior and lateral), in order to assess which is more closely correlated with body size and locomotor agility. Measurements were computed from 3D landmarks taken from magnetic resonance images of a diverse sample of placental mammals encompassing 16 eutherian orders. Body masses were collected from the literature and an agility score was assigned to each species. The R and P/L of all three semicircular canals were found to have highly significant positive correlations with each other and no statistical difference was found between the slope of 2P/L against R and 1. This indicated that, contrary to initial hypotheses, there is little difference between 2P/L and R as measures of semicircular canal size. A measure of the in-plane circularity of the canal was obtained by dividing 2P/L by R and out-of-plane torsion was measured as angular deviation from a plane of best fit. It was predicted that deviations from in-plane and out-of-plane circularity would increase at small body size due to the constraints of fitting a proportionately larger canal into a smaller petrous bone. However, neither measurement was found to have a significant correlation with body mass, indicating that deviations from circularity (both in-plane and out-of-plane) are not sufficient to alter P/L to an extent that would impact the sensitivity of the canals. 2P/L and R were both shown to be significantly correlated with

  1. The bony labyrinth of the middle Pleistocene Sima de los Huesos hominins (Sierra de Atapuerca, Spain).

    PubMed

    Quam, Rolf; Lorenzo, Carlos; Martínez, Ignacio; Gracia-Téllez, Ana; Arsuaga, Juan Luis

    2016-01-01

    We performed 3D virtual reconstructions based on CT scans to study the bony labyrinth morphology in 14 individuals from the large middle Pleistocene hominin sample from the site of the Sima de los Huesos (SH) in the Sierra de Atapuerca in northern Spain. The Atapuerca (SH) hominins represent early members of the Neandertal clade and provide an opportunity to compare the data with the later in time Neandertals, as well as Pleistocene and recent humans more broadly. The Atapuerca (SH) hominins do not differ from the Neandertals in any of the variables related to the absolute and relative sizes and shape of the semicircular canals. Indeed, the entire Neandertal clade seems to be characterized by a derived pattern of canal proportions, including a relatively small posterior canal and a relatively large lateral canal. In contrast, one of the most distinctive features observed in Neandertals, the low placement of the posterior canal (i.e., high sagittal labyrinthine index), is generally not present in the Atapuerca (SH) hominins. This low placement is considered a derived feature in Neandertals and is correlated with a more vertical orientation of the ampullar line (LSCm < APA), posterior surface of the petrous pyramid (LSCm > PPp), and third part of the facial canal (LSCm < FC3). Some variation is present within the Atapuerca (SH) sample, however, with a few individuals approaching the Neandertal condition more closely. In addition, the cochlear shape index in the Atapuerca (SH) hominins is low, indicating a reduction in the height of the cochlea. Although the phylogenetic polarity of this feature is less clear, the low shape index in the Atapuerca (SH) hominins may be a derived feature. Regardless, cochlear height subsequently increased in Neandertals. In contrast to previous suggestions, the expanded data in the present study indicate no difference across the genus Homo in the angle of inclination of the cochlear basal turn (COs < LSCm). Principal components