Endoscopic Transnasal Transmaxillary Approach to Orbital Apex through the Meningo-Orbital Band: A Cadaveric Feasibility Study.

Background: Extradural transcranial release of the meningo-orbital band occupying the lateral part of the superior orbital fissure is used to approach the orbital apex and middle cranial fossa. The authors tested the feasibility of the release of the meningo-orbital band via an endonasal transmaxillary approach. Materials and Methods: Five injected cadaveric heads were assessed for dimensions of superior orbital fissure by computerized tomography. An endonasal transsphenoid transpterygoid approach was done to the superior orbital fissure and annulus of Zinn medially, down to the maxillary nerve. The periorbita was dissected superolaterally to expose the greater wing of the sphenoid and the meningo-orbital band. The superior orbital fissure was decompressed inferiorly by drilling the greater wing of the sphenoid and the maxillary strut after transposition of the maxillary nerve. The meningoorbital band was cut at the junction of the lateral part of the superior orbital fissure and the periorbita exposing the frontotemporal dural junction. The edge of the lesser wing of the sphenoid was drilled toward the annulus of Zinn and the optic canal. The temporal lobe dura was separated from the periorbita and lateral cavernous dural wall at the meningo-orbital band and the ophthalmic nerve. Results: The superior orbital fissure had an oblique angle (mean: 39 ± 2.75 degrees) to the midsagittal plane, the length of its lateral part corresponding to the meningo-orbital band was (mean: 6.08 ± 2.58 mm) and the distance from its lateral end to midline was (mean 2.97 ± 0.11 cm). The meningo-orbital band was released in 10 cadaveric head sides with a distinct plane between the periorbita and the dura propria. Transmaxillary endoscopy provided less orbital retraction and better visualization of the lateral wall of the cavernous sinus. Conclusion: Endonasal transmaxillary release of the meningoorbital band is feasible, allowing exposure of the orbital apex and the middle cranial fossa.

Imaging spectrum of acute invasive fungal rhino-orbital-cerebral sinusitis in COVID-19 patients: A case series and a review of literature.

BACKGROUND: The incidence of devastating opportunistic coinfections in patients with COVID-19 infection, their imaging features and their morbidity and mortality consequences need to be unraveled. METHODS: This is a case series presenting the radiologic features and clinical presentation of acute invasive fungal rhino-orbital-cerebral sinusitis (AIFS) in eight hospitalized patients with confirmed COVID-19 infection. RESULTS: Our patient cohort presented with symptoms of the invasive fungal disease within 12-35 days from their initial presentation with COVID-19 infection. The cross-sectional imaging features of AIFS associated with COVID-19 infection do not differ from those reported in the literature for AIFS associated with other risk factors, yet our patients had features of aggressive late-stage forms with high morbidity and mortality rate. CONCLUSION: AIFS is a possible encounter in patients with COVID-19 patients and radiologists should be familiar with its imaging features.

Spike in Rhino-Orbital-Cerebral Mucormycosis Cases Presenting to a Tertiary Care Center During the COVID-19 Pandemic.

Objective: To determine if there was an increase in the rate of cases presenting with rhino-orbital-cerebral mucormycosis (ROCM) to a tertiary care center during the first wave of the coronavirus disease 2019 (COVID-19) pandemic and the characteristics of the presenting cases. Methods: Retrospective observational study reviewing ROCM cases presenting from March 25 until September 25, 2020. Cases fulfilling the clinical, radiological, and pathological/microbiological criteria for diagnosis with ROCM were included. The number of cases presenting during the designated interval, their COVID-19 status, comorbidities, and clinical presentation were analyzed. The number of cases during the corresponding interval in the previous 3 years was used as reference to detect if there was a recent spike. Results: Of the 12 ROCM cases identified, 5 had a concurrent positive reverse transcription PCR (RT-PCR) test result for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), 1 had a prior positive result, and 6 did not have concurrent nor prior positive test results. Nine of the 12 cases had poorly controlled diabetes mellitus, and 2 cases had a hematological malignancy. All cases had orbital invasion, and eight cases had cerebral invasion. The number of cases identified during the interval is much higher than the numbers presenting in the prior 3 years during equivalent intervals (range, one to two cases) than those reported in the literature in different settings in the pre-pandemic era. Conclusions: There is an increased rate of ROCM cases presenting to our center during the first wave of the COVID-19 pandemic. This is a preliminary report, and further studies are needed to corroborate the findings and explain possible underlying links.

Endoscopic transorbital ligation of the maxillary artery through the inferior orbital fissure.

OBJECTIVE: Determine the feasibility of accessing the internal maxillary artery (IMA) through a transorbital endoscopic assisted approach through the inferior orbital fissure (IOF). MATERIALS AND METHODS: Six adult cadaveric specimens were injected intravascularly with colored latex and dissected on 12 sides. A transorbital endoscopic approach was used to expose the IOF and reach the IMA. RESULTS: The average length and width of the anterolateral segment of the IOF were 7.3 and 4 mm, respectively, on the right side and 6.7 and 3.8 mm, respectively, on the left side. Surgical exposure and modification of the IOF allowed the exposure and control of the IMA in all 12 sides. CONCLUSIONS: The IOF is a feasible portal to the IMA. The benefits of this approach include vascular control of the distal segment of the maxillary artery. It may provide access in clinical scenarios where endonasal access is not possible (e.g., extensive tumors) or serve as an alternative or complementary surgical route (e.g., control during a total or radical maxillectomy).