Effects of Modified Osteoplastic Pterional Craniotomy on Temporal Muscle Volume and Frontal Muscle Nerve Function

Introduction Pterional craniotomy is a surgical approach frequently used in aneurysm and skull base surgery. Pterional craniotomy may lead to cosmetic and functional problems, such as eyebrow drop due to facial nerve frontal branch damage, temporal muscle atrophy, and temporomandibular joint pain. The aim was to compare the postoperative effects of our modified osteoplastic craniotomy with classical pterional craniotomy in terms of any change in volume of temporal muscle and in the degree of frontal muscle nerve damage. Materials and Methods Aneurysm cases were operated with either modified osteoplastic pterional craniotomy or free bone flap pterional craniotomy according to the surgeon's preference. Outcomes were compared in terms of temporal muscle volume and frontal muscle nerve function 6 months postoperatively. Results Preoperative temporal muscle volume in the modified osteoplastic pterional and free bone flap pterional craniotomy groups were not different (p > 0.05). However, significantly less atrophy was observed in the postoperative temporal muscle volume of the osteoplastic group compared with the classical craniotomy group (p < 0.001). In addition, when comparing frontal muscle nerve function there was less nerve damage in the modified osteoplastic pterional craniotomy group compared with the classical craniotomy group, although this did not reach significance (p > 0.05). Conclusion Modified osteoplastic pterional craniotomy significantly reduced atrophy of temporal muscle and caused proportionally less frontal muscle nerve damage compared with pterional craniotomy, although this latter outcome was not significant. These findings suggest that osteoplastic craniotomy may be a more advantageous intervention in cosmetic and functional terms compared with classical pterional craniotomy.

Minipterional approach for anterior circulating aneurysms

The minipterional approach is less invasive than pterional craniotomy and uses the gravity as an ally. Patient’s head position is a key, due to deflection and rotation of aneurysms. This is a brief note aiming to describe the approach step-by-step.

Suprafascial dissection for pterional craniotomy to preserve the frontotemporal branch of the facial nerve with less temporal hollowing

Background: To protect the frontotemporal branch of the facial nerve (FTFN) when performing pterional craniotomy, several reports suggest the subfascial or interfascial dissection technique. However, the reports of postoperative frontalis paralysis and temporal hollowing, which are common complications, were relatively limited. This study reports the incidence of postoperative frontalis paralysis and temporal hollowing after pterional craniotomy using the suprafascial and interfascial techniques. Methods: Patients who underwent pterional craniotomy, using the suprafascial technique (leaving the muscle cuff and not leaving the muscle cuff) and the interfascial technique, between November 2015 and September 2018 were retrospectively evaluated for postoperative frontalis paralysis and temporal hollowing using Chi-squared/ Fisher exact test. Results: Seventy-two patients underwent pterional craniotomy, using the suprafascial technique in 54 patients (leaving the muscle cuff in 21 patients and not leaving the muscle cuff in 33 patients) and the interfascial technique in 18 patients. Eleven patients (20.4%) in the suprafascial group and 1 patient (5.6%) in the interfascial group developed transient frontalis paralysis (P = 0.272). No permanent frontalis paralysis was observed. Obvious temporal hollowing occurred in 18.2% of patients in the suprafascial group without the muscle cuff, in 64.3% of patients in the suprafascial group with the muscle cuff, and in 72.7% of patients in the interfascial group (P = 0.003). Conclusion: The suprafascial dissection technique does not cause permanent injury of the FTFN, and this approach results in a significantly lower incidence of postoperative temporal hollowing than interfascial dissection, especially without leaving a temporalis muscle cuff.

Esthetics outcomes in patients submitted to pterional craniotomy and its variants: A scoping review

Background: Highly performed nowadays, the pterional craniotomy (PC) has several widespread variants. However, these procedures are associated with complications such as temporalis muscle atrophy, facial nerve frontal branch damage, and masticatory difficulties. The postoperative cranial aesthetic is, nonetheless, the main setback according to patients. This review aims to map different pterional approaches focusing on final aesthetics. Methods: This review follows the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. Studies were classified through the Oxford method. We searched PubMed/MEDLINE, EMBASE, and Cochrane Library from January 1969 to February 2021 for cohorts and randomized clinical trials that met our inclusion criteria. Results: 1484 articles were initially retrieved from the databases. 1328 articles did not fit the inclusion criteria. 118 duplicates were found. 38 studies were found eligible for the established criteria. 27 (71.05%) were retrospective cohorts, with low evidence level. Only 5 (13.15%) clinical trials were found eligible to the criteria. The majority of the studies (36/38) had the 2B OXFORD evidence level. A limited number of studies addressed cosmetic outcomes and patient satisfaction. The temporal muscle atrophy or temporal hollowing seems to be the patient’s main complaint. Only 17 (44.73%) studies addressed patient satisfaction regarding the aesthetics, and only 10 (26.31%) of the studies reported the cosmetic outcome as a primary outcome. Nevertheless, minimally invasive approaches appear to overcome most cosmetic complaints and should be performed whenever possible. Conclusion: There are several variants of the classic PC. The esthetic outcomes are poorly evaluated. The majority of the studies were low evidence articles.

Cavernous Sinus Epidermoid Cyst Removal through a No-Keyhole Pterional Craniotomy: Operative Video and Technical Nuances

Intracranial epidermoid cysts are considered benign tumors with good general prognosis. However, their radical removal may be associated with certain morbidity, especially when the capsule is attached to neurovascular structures. Epidermoid cysts located in the cavernous sinus are very rare. We present an operative video of a 22-year-old female patient, who suffered a right-sided headache for 5 years. The video demonstrates main steps and surgical nuances of resection of a right interdural cavernous sinus epidermoid cyst, measuring 22 × 19 × 21 mm (4.3 cc) (Fig. 1A). On initial physical examination, the patient had a right partial third nerve palsy (mild ptosis with minimal diplopia), without any other cranial nerve deficit. A right no-keyhole pterional craniotomy was performed, followed by extradural anterior clinoidectomy and peeling of the outer dural layer of the lateral wall of the cavernous sinus. The dura matter was also detached from the distal carotid dural ring, which was exposed by the clinoidectomy (Fig. 2A). This maneuver provided excellent exposure of the interdural epidermoid cyst, which severely compressed the oculomotor nerve against the posterior petroclinoid dural fold (Fig. 2B). Gross total resection of the epidermoid cyst was achieved (Fig. 1B and C). The patient developed a transient worsening of the third nerve palsy, which recovered completely 3 months after the surgery. Postoperative magnetic resonance imaging revealed no signs of residual tumor.The link to the video can be found at: https://youtu.be/pobhYb5ZNig.

Comparative study between minimally invasive supraorbital craniotomy and pterional craniotomy for treating anterior circulation cerebral aneurysms in a low-resource setting

The challenges encountered in performing minimally invasive approaches, such as supraorbital minicraniotomy (SOMC), in services without adequate equipment are rarely reported in the literature. This study analyzes the viability of SOMC in the treatment of cerebral aneurysms, using exactly the same resources as pterional craniotomy (PC). The results of these two techniques are compared. 35 patients underwent SOMC, compared to 50 patients underwent CP (100 aneurysms in total), using the same microsurgical instruments. The following variables were compared: operative time, angiographic cure, length of intensive care unit stay during the post-operative period, surgical complications, length of hospital stay after surgery until hospital discharge, intraoperative aneurysm rupture, aesthetic satisfaction with the scar, and neurological status at discharge. SOMC had a significantly shorter operative time in relation to PC (213.9 ± 11.09 min and 268.6 ± 15.44 min, respectively) (p = 0.0081).With respect to the cosmetic parameters assessed by the Visual Analog Scale, the average for SOMC was 94.12 ± 1.92 points, and the average for PC was 83.57 ± 4.75 points (p = 0.036). SOMC was as effective as PC in relation to successful aneurysm clipping (p = 0.77). The SOMC technique did not show advantages over PC in any other variable. Even in a general neurosurgery service lacking a specific structure for minimally invasive surgeries, SOMC was feasible and effective for treating intracranial aneurysms, using the same set of microsurgical instruments used for PC, obtaining better results in operating time and cosmetic satisfaction.

The pterional approach for the surgical resection of an orbital cholesteatoma: a case report

Background Cholesteatomas are benign tumors mainly composed of cholesterol crystals that rarely arise within the orbit. However, orbital cholesteatomas require a complete surgical resection due to their recidivating potential. Transcranial approaches offering a broad surgical exposure of the orbital cavity have been scarcely used for the management of these tumors. Here, we provide evidence of the benefits of the pterional craniotomy for the surgical resection of orbital tumors by sharing our experience in the surgical management of a cholesteatoma of the superotemporal orbital wall. Case presentation A 45-year-old Hispanic man with a 2-year history of progressive proptosis of the left eye attended to our center complaining of diplopia and migraine. At his arrival, physical examination revealed ptosis, palpebral edema, and exophthalmos of the left eye, as well as the abolishment of the ipsilateral photomotor and consensual responses. Fundoscopy showed mild optic atrophy, whereas a T2-weighted magnetic resonance imaging (MRI) of the head showed a hyperintense mass arising at the superotemporal wall of the orbit that was displacing the eyeball. The tumor was resected using a pterional craniotomy without postoperative complications. The histopathological analysis of the tumor revealed a cholesteatoma. The patient recovered the functionality of the left eye with no visual sensitive deficits nor tumor recurrence 1 year after the surgery. Conclusions Our results support the use of the pterional craniotomy as a safe procedure for the surgical resection of cholesteatomas arising at the superotemporal walls of the orbit, with low postoperative morbidity.