Are the Ethmoidal Foramina Through the Frontal Bone, Ethmoid Bone, or Frontoethmoidal Suture?

INTRODUCTION: To investigate the locations of the anterior, middle, and posterior ethmoidal foramina and their relationships to the frontoethmoidal suture. METHODS: One hundred twenty sides from sixty adult human skulls were used. Specimens with significant damage to the medial orbit wall were excluded. The number of ethmoidal foramina (anterior, middle, and posterior) on the medial orbital wall and the relationship of each foramen to the frontoethmoidal suture were recorded and classified as follows: Type I: superior to the frontoethmoidal suture; Type II: on the frontoethmoidal suture; Type III: inferior to the frontoethmoidal suture. RESULTS: Of the ninety-four sides, fourteen (14.9%) had one foramen, sixty-two (66.0%) had two , and eighteen (19.1%) had three. In total, 192 ethmoidal foramina were observed. Among the fourteen sides with one foramen, eight foramina were anterior and six were posterior. Among the 192 ethmoidal foramina, 162 were eligible for fur ther classification (74 anterior, 14 middle, and 74 posterior). Types I, II, and III ethmoidal foramina were found in 38.3% (62/162), 61.7% (100/162), and 0% (0/162), respectively. CONCLUSIONS: Our current study found a higher incidence of type I than previously reported. It is important to be aware of the significant incidence of foramen variations when the medial orbit wall is manipulated during surgery. Unless caution is observed, an inadvertent surgical injury can occur and lead to life-threatening complications. Therefore, a good understanding of orbital anatomy and its potential variations is critical for improving patient out comes.

Effects of the COVID-19 Pandemic on Operative Volume and Residency Training at Two Academic Neurosurgery Centers in New Orleans.

BACKGROUND: Medical subspecialties including neurosurgery have seen a dramatic shift in operative volume in the wake of the coronavirus disease 2019 (COVID-19) pandemic. The goal of this study was to quantify the effects of the COVID-19 pandemic on operative volume at 2 academic neurosurgery centers in New Orleans, Louisiana, USA from equivalent periods before and during the COVID-19 pandemic. METHODS: A retrospective review was conducted analyzing neurosurgical case records for 2 tertiary academic centers from March to June 2020 and March to June 2019. The records were reviewed for variables including institution and physician coverage, operative volume by month and year, cases per subspecialty, patient demographics, mortality, and morbidity. RESULTS: Comparison of groups showed a 34% reduction in monthly neurosurgical volume per institution during the pandemic compared with earlier time points, including a 77% decrease during April 2020. There was no change in mortality and morbidity across institutions during the pandemic. CONCLUSIONS: The COVID-19 pandemic has had a significant impact on neurosurgical practice and will likely continue to have long-term effects on patients at a time when global gross domestic products decrease and relative health expenditures increase. Clinicians must anticipate and actively prepare for these impacts in the future.

Spinal pigmented villonodular synovitis and tenosynovial giant cell tumor: A report of two cases and a comprehensive systematic review.

BACKGROUND AND OBJECTIVE: Pigmented villonodular synovitis (PVNS) is a lesion of uncertain etiology that involves the synovial membranes of joints or tendon sheaths, representing a diffuse and non-encapsulated form of the more common giant cell tumors of the synovium (GCTTS). PVNS was reclassified to denote a diffuse form of synovial giant cell tumor (TSGCT), while 'giant cell tumor of the tendon sheath (GCTTS)' was used for localized lesions. These pathologies rarely affect the axial skeleton. We provide an unprecedented and extensive systematic review of both lesions highlighting presentation, diagnostic considerations, treatment, prognosis, and outcomes, and we report a short case-series. METHOD: We describe two-cases and conduct a systematic review in accordance with PRISMA guidelines. RESULT: PVNS was identified in most of the cases reviewed (91.6 %), manifesting predominantly in the cervical spine (40 %). Patients commonly presented with neck pain (59 %), back pain (53 %), and lower back pain (81.2 %) for cervical, thoracic, and lumbar lesions, respectively. GTR occurred at rates of 94 %, 80 %, and 87.5 %. Recurrence was most common in the lumbar region (30.7 %). GCTTS cases (8%) manifested in the cervical and thoracic spine at the same frequency. We reported first case of GCTTS in the lumbosacral region. Both poses high rate of facet and epidural involvements. CONCLUSION: Spinal PVNS and GCTTS are rare. These lesions manifest most commonly as PVNS within the cervical spine. Both types have a high rate of facet and epidural involvement, while PVNS has the highest rate of recurrence within the lumbar spine. The clinical and radiological features of these lesions make them difficult to differentiate from others with similar histogenesis, necessitating tissue diagnosis. Proper management via GTR resolves the lesion, with low rates of recurrence.

Cerebellar pleomorphic xanthoastrocytoma in the setting of neurofibromatosis type-I: Does it portend a different prognosis? A case report and systematic review.

BACKGROUND: Pleomorphic xanthoastrocytoma (PXA) is a rare brain tumor occurring supra- and infra-tentorially in both young adults and children. PXA is a benign tumor with a favorable prognosis. It is not traditionally considered as a neurofibromatosis type 1 (NF-1)-associated lesion, and its prognosis remains largely unknown, on the contrary to non-NF-1 PXA tumors. OBJECTIVE: Herein, we present a rare case of cerebellar PXA in a patient with NF-1 and performed systematic review of NF-1-associated PXA. METHOD: We present a case of NF-1-associated PXA arising in the cerebellar region. We also reviewed the literature in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines to identify published cases of cerebellar vs. non-cerebellar NF-1-associated PXA and NF1 vs. non-NF1 PXAs, highlighting their management paradigm, prognosis, and outcomes. RESULT: Our systematic review yielded only four previously reported cases of NF-1-associated PXAs in the cerebellar region. Our review suggests that infratentorial PXAs have a higher recurrence and lower survival rates than non-cerebellar NF-1-associated PXAs and non-NF1 PXAs in general. CONCLUSION: Early and precise diagnosis is important for these lesions with the aid of imaging features, histology, immunohistochemistry, and genetic markers. Surgical resection with goal of GTR remains the mainstay management strategy for PXA, with adjuvant therapy usually reserved for anaplastic or malignant lesions. The identification of BRAF-V600E mutation and role of BRAF inhibitors hold promise as a diagnostic tool and treatment modality, respectively, for PXAs, and their relationship to NF-1 is worth further exploration.