Embolization of Internal Carotid Artery Branches in Juvenile Nasopharyngeal Angiofibroma

OBJECTIVE

Preoperative embolization of juvenile nasopharyngeal angiofibroma (JNA) is usually performed by the occlusion of branches of the external carotid artery (ECA). However, a significant proportion of JNAs also receive blood from the internal carotid artery (ICA). The objective of this study was to report on the feasibility and clinical impact of superselective embolization of ICA branches in complex cases of JNA.

METHODS

This was a single-center retrospective study of all patients operated on for JNA between 2000 and 2018. The patients treated with embolization of branches of the ICA were identified. The results in terms of complications, intraoperative blood loss, and rate of residual disease were analyzed and compared to those of a control group of patients treated only with embolization of ECA branches and matched by age, stage, angiographic pattern, surgical approach, and previous surgery.

RESULTS

Ninety-two patients were included. Embolization of branches of the ICA was attempted in 14 cases of advanced or recurrent tumors and was ultimately possible in nine cases. There were no complications after embolization. The mean intraoperative blood loss was 1428 mL. Residual disease was found in three cases (33%). There was no significant difference compared with the control group (mean intraoperative blood loss = 1355 mL, residual disease = 4 (44%); all P > .05).

CONCLUSION

In this retrospective study, we report the feasibility of superselective embolization of ICA branches in selected cases of JNA. There was no observed benefit of this technique in terms of intraoperative bleeding or decreased risk of residual disease.

LEVEL OF EVIDENCE

4 Laryngoscope, 131:E775-E780, 2021.

The pterygoclival ligament: a novel landmark for localization of the internal carotid artery during the endoscopic endonasal approach

OBJECTIVE

The transpterygoid extension of the endoscopic endonasal approach provides exposure of the petrous apex, Meckel's cave, paraclival area, and the infratemporal fossa. Safe and efficient localization of the lacerum segment of the internal carotid artery (ICA) is a crucial part of such exposure. The aim of this study is to introduce a novel landmark for localization of the lacerum ICA.

METHODS

Ten cadaveric heads were prepared for transnasal endoscopic dissection. The floor of the sphenoid sinus was drilled to expose an extension of the pharyngobasilar fascia between the sphenoid floor and the pterygoid process (the pterygoclival ligament). Several features of the pterygoclival ligament were assessed. In addition, 31 dry skulls were studied to assess features of the bony groove harboring the pterygoclival ligament.

RESULTS

The pterygoclival ligament was identified bilaterally during drilling of the sphenoid floor in all specimens. The ligament started a few millimeters posterior to the posterior end of the vomer alae and invariably extended posterolaterally and superiorly to blend into the fibrous tissue around the lacerum ICA. The mean length of the ligament was 10.5 ± 1.7 mm. The mean distance between the anterior end of the ligament and midline was 5.2 ± 1.2 mm. The mean distance between the posterior end of the ligament and midline was 12.3 ± 1.4 mm. The bony pterygoclival groove was identified at the confluence of the vomer, pterygoid process of the sphenoid, and basilar part of the occipital bone, running from posterolateral to anteromedial. The mean length of the groove was 7.7 ± 1.8 mm. Its posterolateral end faced the anteromedial aspect of the foramen lacerum medial to the posterior end of the vidian canal. A clinical case illustration is also provided.

CONCLUSIONS

The pterygoclival ligament is a consistent landmark for localization of the lacerum ICA. It may be used as an adjunct or alternative to the vidian nerve to localize the ICA during endoscopic endonasal surgery.