Endoscopic Temporalis Tendon Extension (ETTE)

Many techniques have been proposed to restore facial symmetry in facial nerve palsies. This study presents our surgical approach called Endoscopic Temporalis Tendon Extension (ETTE). After nasotracheal intubation, a 4 cm skin incision is made at the nasolabial fold. Under endoscopic view, the medial face of the masseter muscle is detached from the mandibular ramus. The coronoid process is then sectioned by Piezosurgery®. Finally, a fascia lata graft is suspended between the temporalis tendon and the orbicularis oris. ETTE is a mixed technique, with a static suspension component and a dynamic contraction one. The preservation of the temporalis muscle insertion in temporal fossa allows for an optimal contraction. A fascia lata graft is necessary for reasons of length. The scar produced by the nasolabial incision allows to recreate the missing nasolabial fold. The endoscopic assistance provides greater precision during the procedure and entails a shorter learning curve.

Retrosigmoid versus Retrolabyrinthine Posterior Petrosal Route to the Petroclival Area: Quantitative Assessment of Endoscope-Assisted Approaches and Correlations with Morphometric Features

OBJECTIVE

Using a cadaveric model, we compared endoscope-assisted retrosigmoid (EAR) and endoscope-assisted retrolabyrinthine posterior petrosal (EARPP) approaches towards the petroclival area, regarding surgical exposure and instrument maneuverability, also verifying how some petroclival morphometric parameters correlate with these variables.

METHODS

In five cadaver heads, EAR approach was performed on one side and EARPP on the other (10 approaches). Under endoscopic view, neuronavigation coordinates were acquired to compute areas of exposure (petroclival and pontomedullary) and maneuverability at Dorello's canal entrance to run the comparison. Correlations of these variables with petroclival angle and clival depth were also analyzed.

RESULTS

EAR and EARPP showed equivalence regarding surgical exposure (petroclival: 365.85 ± 133.12 mm² and 320.62 ± 103.44 mm², respectively, P = 0.69; pontomedullary: 255.83 ± 88.26 mm² and 229.80 ± 74.39 mm², respectively, P = 0.83), but EAR afforded greater maneuverability at Dorello's canal (1155.88 ± 134.35 mm², P = 0.03). The petroclival angle and clival depth showed different strong correlations with maneuverability depending upon the route, but not with surgical exposure in both approaches.

CONCLUSIONS

Endoscopic techniques can spare the need for additional steps of greater morbidity when approaching the petroclival area in both routes. A simpler and faster approach as EAR was favored over EARPP in this standardized quantitative assessment. The petroclival angle and clival depth may interfere with maneuverability, but not with surgical exposure in both endoscope-assisted approaches.

From the Occipital Condyle to the Sphenoid Sinus: Extradural Extension of the Far Lateral Transcondylar Approach with Endoscopic Assistance

BACKGROUND

Surgical management of extensive skull base tumors, such as chordoma and chondrosarcoma, remains very challenging. The need for gross total removal to improve survival must be weighed against the risk of injury to neurovascular structures and the loss of stability at the craniovertebral junction. In cases of tumors that are already compromising craniovertebral junction stability, the occipital condyle can be exploited as a deep keyhole to reach the clivus, petrous apex, and sphenoid sinus.

METHODS

We performed an anatomic study on 7 cadaveric specimens to describe the main landmarks and boundaries of the corridor. We also provide a clinical case to demonstrate the feasibility of the approach.

RESULTS

In all specimens, using the space provided by the condyle, it was possible to drill the petrous bone up to the posterior wall of the sphenoid sinus following the direction of the inferior petrosal sinus. To successfully complete the approach, after the hypoglossal canal was exposed, endoscopic assistance was needed to overcome the narrowing of the visual field provided by the microscope.

CONCLUSIONS

In cases of invasive skull base tumor involving the craniovertebral junction and affecting its stability, the occipital condyle can be exploited as a deep keyhole to the homolateral and contralateral petrous apex, clivus, and sphenoid sinus.

Endoscopically Assisted Targeted Keyhole Retrosigmoid Approaches for Microvascular Decompression: Quantitative Anatomic Study

OBJECTIVE

We describe and quantitatively assess minimally invasive keyhole retrosigmoid approaches targeted to the upper, middle, and lower cranial nerve (CN) complexes of the cerebellopontine angle (CPA).

METHODS

Anatomic dissections were performed on 10 sides of 5 fixed, silicone-injected cadaver heads. Surgical views through various trajectories were assessed in endoscopic videos and 3-dimensional (3D) interactive virtual reality microscope views. Surgical freedom and angles of attack to the proximal and distal areas of CN complexes of the CPA were compared among upper and lower keyholes and conventional retrosigmoid craniotomy using neuronavigation.

RESULTS

Compared with keyholes, the conventional approach had superior surgical freedom to most areas except for the distal CN V, the root of CN VII, and the root of CN IX, where differences were not significant. The conventional retrosigmoid approach provided a larger horizontal angle of attack than either the upper or lower keyholes for all selected areas; however, the vertical angles of attack were not different. Splitting the petrosal fissure resulted in a significant increase in the vertical angle of attack to the root zones of CNs V and VII but not to the distal areas of these nerves or CN IX. Illustrative cases of endoscope-assisted keyhole retrosigmoid approaches for the treatment of trigeminal neuralgia, hemifacial spasm, and glossopharyngeal neuralgia are presented.

CONCLUSIONS

Targeted keyhole retrosigmoid approaches require detailed understanding of the 3D anatomy of the CPA to create appropriate locations of corridors, including skin incisions and keyholes. Endoscope assistance complements the standard microsurgical technique by maximizing the visualization and identification of the delicate neurovascular structures.

Short- and Long-Term Outcomes of Endoscope-Assisted Laparoscopic Wedge Resection for Gastric Submucosal Tumors Adjacent to Esophagogastric Junction

BACKGROUND

Laparoscopic wedge resection (LWR) is used to treat gastric submucosal tumors (SMTs). However, LWR can injure the cardia if tumors are near the esophagogastric junction (EGJ), resulting in gastric stenosis. This study's purpose was to summarize our experience with endoscope-assisted LWR for gastric SMTs within 3 cm of the EGJ and to verify the procedure's feasibility and safety.

METHODS

Data from 91 consecutive patients with gastric SMTs within 3 cm of the EGJ who underwent endoscope-assisted LWR at our hospital from 2007 to 2017 were obtained from a prospectively maintained database. The clinicopathological results, perioperative data, and long-term follow-up data were analyzed.

RESULTS

All patients successfully underwent endoscope-assisted LWR. The mean distance from tumor to EGJ was 2.43 ± 0.80 cm. Eighty-two patients underwent laparoscopic exogastric wedge resection (LEWR) and nine underwent laparoscopic transgastric wedge resection (LTWR). Mean operative time was 112.4 ± 48.8 min; mean blood loss was 36.8 ± 53.5 ml. Mean time to first flatus was 2.04 ± 0.68 days. Mean time to liquid intake was 2.53 ± 0.85 days. Mean postoperative hospital stay was 4.97 ± 1.80 days. Three patients (3.3%) had postoperative complications, all Clavien-Dindo grade I. The mean maximum tumor diameter was 3.00 ± 1.96 cm (range 0.5-10). LTWR was used more often than LEWR for SMTs in the posterior wall, those with intraluminal growth, and those closer to the EGJ. The mean follow-up time was 36.86 ± 29.73 months (range 3-126). There was no stenosis of EGJ or tumor recurrence. Sixteen patients (17.6%) complained of upper gastrointestinal symptoms during the follow-up, which were all relieved by usage of acid suppressive medications.

CONCLUSIONS

Endoscope-assisted LWR is safe, feasible, and effective for gastric SMTs near the EGJ. LTWR is preferable to LEWR for gastric SMTs in the posterior wall, those with intraluminal growth, and those closer to the EGJ.

Supraorbital subfrontal trans-laminar endoscope-assisted approach for tumors of the posterior third ventricle

BACKGROUND

Different surgical approaches have been developed for dealing with third ventricle lesions, all aimed at obtaining a safe removal minimizing brain manipulation. The supraorbital subfrontal trans-lamina terminalis route, commonly employed only for the anterior third ventricle, could represent, in selected cases with endoscopic assistance, an alternative approach to posterior third ventricular lesions.

METHODS

Seven patients underwent a supraorbital subfrontal trans-laminar endoscope-assisted approach to posterior third ventricle tumors (two craniopharyngiomas, one papillary tumor of the pineal region, one pineocytoma, two neurocytomas, one glioblastoma). Moreover, a conventional third ventriculostomy was performed via the same trans-laminar approach in four cases.

RESULTS

Complete tumor removal was accomplished in four cases, subtotal removal in two cases, and a simple biopsy in one case. Adjuvant radiotherapy and/or chemotherapy was administered, if required, on the basis of the histologic diagnosis. No major complications occurred after surgery except for an intratumoral hemorrhage in a patient undergoing a biopsy for a glioblastoma, which simply delayed the beginning of adjuvant radiochemotherapy. No ventriculoperitoneal shunt placement was needed in these patients at the most recent clinical and radiologic session (average 39.57 months, range 13-85 months). Two illustrative cases are presented.

CONCLUSIONS

The supraorbital subfrontal trans-laminar endoscope-assisted approach may provide, in selected cases, an efficient and safe route for dealing with posterior third ventricular tumors.

Endoscopic assistance in retrosigmoid transmeatal approach to intracanalicular vestibular schwannomas - An alternative for middle fossa approach. Technical note

BACKGROUND

Complete surgical removal of intracanalicular vestibular schwannomas with nerve VII and VIII sparing and without worsening patient's status is challenging. Also the choice of an optimal surgical technique, which is usually limited to selection between retrosigmoid transmeatal (RT) and middle fossa (MF) approach, can be a challenge. Although many previous studies documented superiority of RT to MF approach and vice versa, still no consensus has been reached regarding an optimal approach to intracanalicular vestibular schwannomas. In this technical note, we present RT approach with an endoscopic assistance and highlight its advantages over MF approach in surgical management of pure intracanalicular vestibular schwannomas.

METHOD

RT approach with an endoscopic assistance is presented as an optimal surgical treatment for intracanalicular vestibular schwannomas, and its advantages are compared to those offered by MF approach.

RESULTS

Under an endoscopic guidance, we found a residual tumor in the fundus of the inner acoustic canal and performed its gross total resection.

CONCLUSIONS

RT approach is an excellent technique suitable for safe radical surgical treatment of T1 vestibular schwannomas; this technique is associated with lower morbidity risk than MF approach.