Modified endoscopic endonasal approach with a minimally invasive transoral approach—an adjunct to infrapetrous approaches

Abstract

Objectives/Hypothesis To evaluate the potential of a minimally invasive transoral–transpalatal approach (MITA) to the retrocarotid petrous apex, as an adjunct to endoscopic endonasal approaches (EEAs). Study Design Cadaver study. Methods Five cadaveric specimens were dissected raising an inverted U‐shaped palatal mucoperiosteal flap, and drilling a rectangular palatotomy (between the greater palatine foramens, and just anterior to the palatine aponeurosis). This allowed a transpterygoid EEA with cross‐court access (contralateral line of sight), followed by an extradural clivectomy that exposed the petroclival junction bilaterally. Surgical targets were marked on the posterior and medial surface of the petrous internal carotid artery (ICA), at its anterior genu, midhorizontal portion, and posterior genu. For each target and approach, the surgical freedom and angles of approach (in the horizontal and vertical planes) were calculated and statistically compared. Results Compared to EEA, the MITA resulted in greater surgical freedom for all targets, with the highest values at the anterior genu (1,661.37 mm2 vs. 312.76 mm2, P <.001), and maintaining superiority in this regard all the way to the posterior genu (847.84 mm3 vs. 138.91 mm3, P < .005). MITA also offered greater angles of approach for all targets. Conclusions This study suggests that the MITA may be indicated to supplement the exposure provided by a transpterygoid EEA. This technique, associated with low potential morbidity, offers an alternative to internal carotid lateralization while managing extradural lesions that are adjacent to the petrous ICA. Level of Evidence NA Laryngoscope, 129:339–343, 2019

Role of resection of torus tubarius to maximize the endonasal exposure of the inferior petrous apex and petroclival area

“…Improvements in techniques and surgical instruments to minimize the need for resection and damage to adjacent structures in the skull base may improve the postoperative quality of life. 19 The Eustachian tube is of critical importance for middle ear function including pressure regulation and hearing. 20 Although tympanostomy and tube insertion can solve the pressure dysfunction, potential hearing loss and worsened middle ear function are still of concern.…”

Endoscopic transoral nasopharyngectomy

“…8 As ETON has a larger surgical freedom when compared to EEN and other minimally invasive approaches. 23 In addition to the increased surgical maneuverability that this signifies, it also indicates a larger operative field in where the use of conventional surgical instruments is possible. This adds an important advantage as it permits the use of tools that surgeons are more familiar and feel more comfortable with, in comparison to endoscopic instrumentation.…”

“…Surgical freedom (SF) and angles of attack (AoA) were calculated on the ICA at its posterior genu (PG), mid-horizontal petrous ICA, and anterior genu (AG), as have been previously described for other minimally invasive approaches. [23][24][25] SF is calculated by moving the proximal end of the instrument as far lateral, medial, superior, and inferior as possible in order to determine an area. It indicates the maximum area in which a surgeon is able to move the proximal end of the instrument while the distal end is fixed on a target.…”

“…Surgical freedom (SF) and angles of attack (AoA) were calculated on the ICA at its posterior genu (PG), mid‐horizontal petrous ICA, and anterior genu (AG), as have been previously described for other minimally invasive approaches 23‐25 …”

Ventilated Upper Airway Endoscopic Endonasal Procedure Mask: Surgical Safety in the COVID-19 Era

“…Surgical freedom (SF) was calculated. 8-10 It indicates the maximum area in which a surgeon is able to move the proximal end of the instrument while the distal end is fixed on a target and is determined by measuring the maximum distance that the portion of the instrument 1 cm above the nostril can move over an axial and sagittal plane in order to determine an area. Measurements were taken with the distal end of the instrument placed over the tuberculum sellae under 3 different conditions: without any barriers, with the trocar, and with the ventilated procedure mask.…”