OBJECTIVE: Recurrent cerebrospinal fluid (CSF) rhinorrhea caused by sequential, anatomically separated skull base defects is rarely reported in the literature. Neither management nor etiology has been sufficiently investigated. We present an illustrative case and a systematic review of the literature regarding etiology, diagnostics, and management of this rare phenomenon.
METHODS: A systematic literature search looking for articles reporting sequential CSF leaks with multiple skull base defects was performed. Data from included articles were descriptively reported, and the quality of the included studies was assessed with Grading of Recommendations Assessment, Development and Evaluation.
RESULTS: A 71-year-old woman with posttraumatic CSF rhinorrhea and left-sided CSF otorrhea due to a left-sided horizontal fracture of the petrous bone presented at our institution. After initial surgical repair and a 10-week symptom-free interval, CSF rhinorrhea recurred. Imaging revealed a preexisting contralateral meningoencephalocele of the lateral sphenoid recess causing recurrent CSF rhinorrhea most likely after initial traumatic laceration. The defect was successfully treated. A literature search identified 366 reports, 6 of which were included in the systematic review with a total of 10 cases. Quality was deemed good in 8 of 10 cases. The most common location for primary and sequential CSF leaks was along the sphenoid bone (4/10 and 5/10 patients, respectively). All publications except one reported the presence of a meningo (encephalo)cele as cause of the sequential CSF leak.
CONCLUSIONS: Occurrence of recurrent CSF rhinorrhea due to an anatomically separated sequential skull base lesion remains a rare phenomenon. Reassessment of imaging studies and a structured diagnostic workup to detect sequential CSF leaks independent of the primary lesion should is recommended.

UNASSIGNED: Inflammatory myofibroblastic tumor (IMFT) is a rare tumor of unknown etiology. It can involve any part of the body. The IMFT involving the base of skull is rare with only 36 cases reported in the literature. We report a rare case of IMFT of temporal bone with review of literature. A 42 year old male presented with complaints of headache and double vision and MRI brain showed lesion in the right petrous apex region suggestive of a neurogenic mass. He had excision of lesion and histopathology was suggestive of IMFT with IgG4 and ALK positive. He had complete clinical response but a month later he presented with right eyelid ptosis and decreased rotation of eye medially with recurrent lesion on MRI. Patient received radiation by SRT technique and then started on Ceretinib with partial response. The IMFT is rare tumor of unknown etiology and tumors of temporal bone are more aggressive. It is benign but locally invasive tumor. Treatment of IMFT is controversial. Extensive surgery with complete excision has about 80% response rates and with intracranial extension, adjuvant radiation is need. In head and neck IMFT response rates are lower (30 to 40%). Monoclonal antibodies and steroids are used in IMFT at recurrence. In advanced or metastatic ALK positive tumors, Crizotinib is used with a response rate of 50%. Radiotherapy (25 to 30 Gy) induces remission and helps to taper the steroids. Temporal bone IMFT is a rare tumor with multimodality approach and variable response to treatment.

OBJECTIVE: To compare the outcomes of different surgical approaches to petrous apex cholesterol granulomas (PACG).
METHODS: PubMed, Embase, Google Scholar, Cochrane, and Web of Science.
METHODS: Following the Preferred Reporting Items for Systematic Reviews and Meta-analyses-Network Meta-analyses guidelines, databases were searched from inception to November 31, 2022. Studies comparing two or more approaches were included. Reviews and population studies were excluded. The main outcome measures were the resolution of symptoms, serviceable hearing, complication, and revision rates.
RESULTS: The search yielded 2132 studies. After applying inclusion and exclusion criteria, 15 studies remained, consisting of 214 patients treated with lateral approaches (n = 182) or anterior endonasal approaches (n = 32). The efficacy of lateral and anterior endonasal approaches in achieving symptom resolution was comparable (73% vs. 68%, p = 0.5). Both exhibited similar rates of complications (33% vs. 37%, p = 0.3), albeit with distinct profiles. Lateral approaches were associated with higher rates of facial palsy and sensorineural hearing loss (44% vs. 18%, p = 0.03). Anterior endonasal approaches demonstrated higher rates of epistaxis and cerebrospinal fluid leak (15% vs. 1%, p = 0.001). Anterior endonasal approaches exhibited lower revision rates (OR: 0.35, 95% CI: 0.14-0.88). The placement of a stent in both approaches was associated with higher symptom resolution (OR: 5.12, 95% CI: 1.05-9.97) and lower revision rates (OR: 0.71, 95% CI: 0.33-0.92).
CONCLUSIONS: Anterior endonasal approaches yield lower revision rates compared to lateral approaches for PACG. Both approaches demonstrate similar effectiveness in symptom resolution and comparable rates of complications, with distinct profiles. Facial nerve and hearing status are important factors that should be addressed when selecting the approach. Stenting is beneficial.
METHODS: NA Laryngoscope, 134:1540-1550, 2024.

Transpetrosal approaches are known to be associated with a significant risk of complications, including CSF leak, facial palsy, hearing impairment, venous injury, and/or temporal lobe injury. We aimed to evaluate the morbidity of the standard combined petrosal approach (CPA), defined as a combination of the posterior (retrolabyrinthine) and the anterior petrosal approach. We performed a systematic review and meta-analysis of articles reporting on clinical series of patients operated on for petroclival meningiomas through CPA. Studies that used the terminology \"combined petrosal approach\" without matching the aforementioned definition were excluded as well as clinical series that included less than 5 patients. A total of 8 studies were included involving 160 patients. The pooled complication rates were 3% (95% CI, 0.5-5.6) for CSF leak, 8.6% (95% CI, 4.1-13.2%) for facial palsy, 8.2% (95% CI, 3.9-12.6%) for hearing impairment, 2.8% (95% CI, 0.9-6.5%) for venous complications, and finally 4.8% (95%, 1.2-8.4%) for temporal lobe injury. Contrary to the general belief, CPA is associated with an acceptable rate of complications, especially when compared to alternative approaches to the petroclival area. In view of the major advantages like shorter trajectory, multiple angles of surgical attack, and early tumor devascularization, CPA remains an important tool in the armamentarium of the skull base surgeon.

Percutaneous transluminal angioplasty (PTA) and stenting have been used for the treatment of internal carotid artery (ICA) stenosis over the past two decades. A systematic review was performed to understand the efficacy of PTA and/or stenting for petrous and cavernous ICA stenosis. In total, 151 patients (mean age 64.9) met criteria for analysis, 117 (77.5%%) were male and 34 (22.5%) were female. Of the 151 patients, 35 of them (23.2%) had PTA, and 116 (76.8%) had endovascular stenting. Twenty-two patients had periprocedural complications. There was no significant difference in the complication rates between the PTA (14.3%) and stent (14.7%) groups. Distal embolism was the most common periprocedural complication. Average clinical follow up for 146 patients was 27.3 months. Eleven patients (7.5%) out of 146 had retreatment. The treatment of petrous and cavernous ICA with PTA and stenting has relatively significant procedure related complication rates and adequate long-term patency.

The \"presigmoid corridor\" covers a spectrum of approaches using the petrous temporal bone either as a target in treating intracanalicular lesions or as a route to access the internal auditory canal (IAC), jugular foramen, or brainstem. Complex presigmoid approaches have been continuously developed and refined over the years, leading to great heterogeneity in their definitions and descriptions. Owing to the common use of the presigmoid corridor in lateral skull base surgery, a simple anatomy-based and self-explanatory classification is needed to delineate the operative perspective of the different variants of the presigmoid route. Herein, the authors conducted a scoping review of the literature with the aim of proposing a classification system for presigmoid approaches.
The PubMed, EMBASE, Scopus, and Web of Science databases were searched from inception to December 9, 2022, following the PRISMA Extension for Scoping Reviews guidelines to include clinical studies reporting the use of \"stand-alone\" presigmoid approaches. Findings were summarized based on the anatomical corridor, trajectory, and target lesions to classify the different variants of the presigmoid approach.
Ninety-nine clinical studies were included for analysis, and the most common target lesions were vestibular schwannomas (60/99, 60.6%) and petroclival meningiomas (12/99, 12.1%). All approaches had a common entry pathway (i.e., mastoidectomy) but were differentiated into two main categories based on their relationship to the labyrinth: translabyrinthine or anterior corridor (80/99, 80.8%) and retrolabyrinthine or posterior corridor (20/99, 20.2%). The anterior corridor comprised 5 variations based on the extent of bone resection: 1) partial translabyrinthine (5/99, 5.1%), 2) transcrusal (2/99, 2.0%), 3) translabyrinthine proper (61/99, 61.6%), 4) transotic (5/99, 5.1%), and 5) transcochlear (17/99, 17.2%). The posterior corridor consisted of 4 variations based on the target area and trajectory in relation to the IAC: 6) retrolabyrinthine inframeatal (6/99, 6.1%), 7) retrolabyrinthine transmeatal (19/99, 19.2%), 8) retrolabyrinthine suprameatal (1/99, 1.0%), and 9) retrolabyrinthine trans-Trautman\'s triangle (2/99, 2.0%).
Presigmoid approaches are becoming increasingly complex with the expansion of minimally invasive techniques. Descriptions of these approaches using the existing nomenclature can be imprecise or confusing. Therefore, the authors propose a comprehensive classification based on the operative anatomy that unequivocally describes presigmoid approaches simply, precisely, and efficiently.

The authors present a patient and neurosurgical nuances of total resection of recurrent meningioma of posterior surface of petrous bone 65´35´30 mm. The tumor captured two critical zones of posterior cranial fossa with unusual frontal growth and spread from the surface of petrous bone to the fourth ventricle. The neoplasm filled the ventricle without lesion of ependyma. Extensive fibrous meningioma of posterior surface of petrous bone was totally excised 18 years ago. MRI was annually carried out for 5 years. Surgical nuances that ensured total extraction of tumor without cytoreduction were as follows: 1) en-bloc resection of tumor from the fourth ventricle due to smooth surface of tumor and minimum number of adhesions with cerebellum; MR-confirmed CSF strip between the tumor edges and walls of the ventricle; no signs of hydrocephalus in subtotal ventricular tamponade; 2) unusual frontal tumor growth under 45º required appropriate angular traction of tumor with minimal rotation; 3) traction was followed by sequential appearance of 3 segments of tumor: petrous, apertural and ventricular; 4) topography of the area of lateral eversion of the fourth ventricle was established by identifying the narrowing (constriction) of tumor; 5) in extracting the tumor from the fourth ventricle, we performed minimal rotation to avoid damage to ventricular walls and lateral aperture due to difference between the larger and smaller diameters (by 6 mm) of ovoid ventricular segment of tumor; 6) no CSF leakage following appearance of ventricular segment (tumor enlargement) indicated integrity of ependyma of the fourth ventricle. Histological examination confirmed fibrous meningioma. Fast and complete regression of focal symptoms was observed after surgery. A 3-year follow-up after surgery revealed no signs of tumor recurrence.
В работе представлены наблюдение и нейрохирургические нюансы тотального удаления рецидивной менингиомы задней поверхности пирамиды височной кости размерами 65×35×30 мм. Опухоль захватывала две критические зоны задней черепной ямки с необычной фронтальной направленностью роста и распространялась от поверхности пирамиды до IV желудочка с заполнением его полости через боковой выворот без поражения эпендимы. По данным анамнеза, 18 лет назад у больного была тотально удалена обширная фиброзная менингиома задней поверхности пирамиды височной кости. На протяжении 5 лет пациента ежегодно обследовали с применением магнитно-резонансной томографии. Хирургические нюансы, позволившие извлечь опухоль целиком без циторедукции, состояли в следующем: 1) удаление узла из полости IV желудочка проведено единым блоком за счет гладкой поверхности опухоли с минимальным количеством спаек с мозжечком на начальном этапе микропрепаровки; наличие ликворной прослойки между краями опухоли и стенками желудочка, что зафиксировано на предоперационных магнитно-резонансных томограммах; отсутствие признаков гидроцефалии при почти полной тампонаде желудочка; 2) необычная фронтальная направленность роста опухоли под углом около 45° требовала соответствующей угловой тракции узла при минимальной его ротации; 3) в процессе тракции отмечено последовательное появление трех сегментов узла: петрозального, апертурального и вентрикулярного; 4) топография области бокового выворота IV желудочка установлена путем выявления сужения (перетяжки) опухолевого узла; 5) при извлечении узла из полости IV желудочка выполнена минимальная ротация во избежание повреждения стенок желудочка и области боковой апертуры в связи с различием большего и меньшего диаметров (на 6 мм) овоидного вентрикулярного сегмента узла; 6) отсутствие истечения ликвора при появлении вентрикулярного сегмента (расширение узла) свидетельствовало о целостности эпендимы IV желудочка. При гистологическом исследовании макропрепарата, как и при первой операции, диагностирована фиброзная менингиома. После операции в неврологическом статусе пациента отмечен быстрый и полный регресс очаговой симптоматики. В процессе трехлетнего наблюдения после операции не выявлены признаки повторного рецидива опухоли.

Petrous temporal bone Cholesteatoma is widely described in the literature and accounts for up to 9% of all neoplasms of this localization. These cholesteatomas rarely spread towards the clivus. Isolated clival cholesteatomas are described only as single cases. There is currently no consensus on the choice of surgical approach for resection of similar neoplasms.
OBJECTIVE: To demonstrate the possibilities of endoscopic transnasal approach in surgery for clival and petrous cholesteatoma.
METHODS: This article presents 3 clinical cases: 2 patients with apical cholesteatoma of petrous part of temporal bone extending to the clivus and 1 patient with massive petrous temporal bone cholesteatoma extending towards the clivus according to the classification of Sanna M. All patients underwent endoscopic transnasal surgery.
CONCLUSIONS: In our opinion, endoscopic transnasal approach is optimal for resection of similar neoplasms. Total and subtotal resection was performed in 2 and 1 case, respectively. However, there are certain limitations of this approach in accessing the most lateral parts of the neoplasm. Nevertheless, endoscopic transnasal approach ensures resection of petrous temporal bone cholesteatoma extending to the clivus without the risk of damage to acoustic-facial cranial nerves. It is especially significant in patients without their baseline dysfunction.
Холестеатомы пирамиды височной кости составляют примерно 9% от всех новообразований этой локализации, редко распространяются в область ската, что подробно описано в литературе. Кроме того, представлены отдельные наблюдения изолированных холестеатом ската. Единого мнения о выборе доступа для удаления подобных новообразований в настоящее время нет.
UNASSIGNED: Продемонстрировать возможности эндоскопического трасназального доступа в хирургии холестеатом области ската и пирамиды височной кости.
UNASSIGNED: В данной статье представлены 3 клинических случая: 2 пациента с апикальной холестеатомой пирамиды височной кости, распространяющейся на скат черепа, и 1 — с массивной холестеатомой пирамиды височной кости, также распространяющейся на скат черепа (согласно классификации M. Sanna). Все пациенты оперированы с использованием эндоскопического трансназального доступа.
UNASSIGNED: Оптимальным для удаления новообразований области ската и пирамиды височной кости, по нашему мнению, является эндоскопический трансназальный доступ. В 2 случаях удалось добиться тотального удаления, в 1 — субтотального. Однако и у этого доступа есть свои ограничения в возможности достижения самых латеральных отделов новообразования.
UNASSIGNED: Использование эндоскопического трансназального доступа обеспечивает возможность удаления холестеатом области пирамиды височной кости, распространяющихся на скат, без риска повреждения акустикофациальной группы черепных нервов, что особенно важно для пациентов без исходного нарушения их функции.

Dorello\'s canal is an arched structure of bone-fibrous character located in the petroclival venous confluence atop the petrosal bone in the petroclival region. It is bordered by the petrosphenoidal ligament, the petrous part of the temporal bone and the lateral border of the upper part of clivus. Its content in the vast majority of variants comprises the abducens nerve, the inferior petrosal sinus, the venous drainage and the dorsal meningeal artery or its medial branch. With the development of microsurgical techniques, this area has gained huge clinical importance, mainly concerning the order in which the above-mentioned elements (especially the position of the abducens nerve) are arranged in relation to each other. These structures appear in different variant forms and necessitate an individual clinical approach. The main purpose of this review is to present condensed information about possible intercorrelations among them and to indicate, on the basis of the available literature and research, possible surgical approaches and the need to consider the variability when treatments in this region are planned.

We report disease remission and recovery of fifth and seventh nerve paresis in a case of primary mucosal melanoma of the middle ear and petrous temporal bone.
A 74-year-old man developed sudden, profound, right sided sensorineural hearing loss, disequilibrium, otalgia, and cranial nerve V and VII dysfunction. Imaging demonstrated an unresectable, osteolytic lesion involving the middle ear and anterior petrous apex. Melanoma was diagnosed via in-office biopsy; whole-body metabolic imaging revealed no other primary site.
Multidisciplinary management included radiation therapy (30 Gy, 10 fractions) followed by induction (five cycles, q2w) and maintenance nivolumab (six cycles, q3w).
Complete metabolic response of primary site and metastases on imaging, recovery of cranial neuropathies.
Following palliative radiation therapy and induction nivolumab, cranial neuropathies resolved. With maintenance-dose nivolumab, primary site and metastases exhibited a complete response. Therapy was stopped at 16 months post-diagnosis. Complete remission was maintained until 22 months after diagnosis. The patient developed a solitary cerebral metastasis which was refractory to radiosurgery and biopsy confirmed melanoma. He expired 2 years, 8 months post-diagnosis.
Mucosal melanoma of the middle ear and petrous temporal bone is exceedingly rare. Management is individualized and surgery is undertaken when possible. Key observations in this case are the complete metabolic response and reversal of cranial nerve neuropathies following radiation and anti-programed cell death receptor ligand 1 therapy. Non-surgical treatment is worthy of study as initial management for similar lesions.