Paraclinoid aneurysms clipping through an extradural sphenoid ridge keyhole approach

BACKGROUND

Paraclinoid aneurysms represent a challenge for neurosurgeons due to the anatomical complexity of this region. Then, innovative techniques such as the extradural sphenoid ridge approach are suitable for a safe microsurgical clipping.

METHOD

A description of the surgical technique was made by the senior author, a vascular neurosurgeon experienced with the use of this approach in the management of paraclinoid aneurysms exemplified through a clinical case.

CONCLUSION

Microsurgical clipping through an extradural sphenoid ridge keyhole approach for small and midsize paraclinoid aneurysms is an excellent treatment modality with good clinical and surgical results.

Small Sphenoid Ridge as a Factor Associated with Laterally Deviated Proximal Sylvian Fissure in Patients Undergoing Pterional Craniotomy

BACKGROUND

During the pterional-transsylvian approach, we sometimes encounter the proximal Sylvian fissure (SF) deviating laterally beyond the fold of the sphenoidal ridge (SR) and experience difficulty dissecting the SF due to the deep and oblique dissection plane. In the present study, we explored the association between the height of the SR and lateral deviation of the SF during the pterional-transsylvian approach.

METHODS

The association between the height of the SR on axial computed tomography and the presence of a laterally deviated SF was evaluated by reviewing patients who had undergone pterional craniotomy.

RESULTS

Among the 52 patients included, lateral deviation of the SF was observed in 8 patients (13.4%). The median height of the SR was significantly smaller in patients with laterally deviated SF (6.0 mm) than in patients with non-deviating SF (13.4 mm; P < 0.0001). The oculomotor nerves and middle fossa were observed at the edge of the dissection plane of the SF in all patients with a laterally deviating SF, while medial structures such as the internal carotid artery or optic nerve were observed in patients with non-deviating SF.

CONCLUSIONS

Small SR was associated with lateral deviation of the proximal SF.

How I do it: total resection of a giant sphenoclinoidal meningioma with normalization of near blind vision

BACKGROUND

Resection of giant sphenoclinoidal meningiomas (SCLM) remains difficult. We discuss a patient presenting with right eye near blindness who underwent total removal of a giant SCLM, resulting in normal vision and no recurrence.

METHOD

Utilizing frontotemporal craniotomy, devascularization, debulking, and detachment was achieved. Microdissection of tumor off the optic nerve and carotid perforators was accomplished, resulting in total resection, visual normalization, and no deficits using efficient face-to-face microscope set-up, 2-surgeon 4-hand technique, and double bipolar-suction arrangement.

CONCLUSION

Frontotemporal craniotomy was adequate. Preservation of the optic nerve and carotid artery is key. Meticulous microsurgical techniques and refined instruments are important for success.

Reappraising the neurosurgical significance of the pterion location, morphology, and its relationship to optic canal and sphenoid ridge and neurosurgical implications

Frontolateral craniotomy procedures have advanced from conventional craniotomy to mini-craniotomy, and to contemporary keyhole surgery. In this context, it is important for the neurosurgeon to precisely locate the pterion. The distance of the pterion center from midpoint of zygomatic arch and posterolateral margin of frontozygomatic suture was studied bilaterally in 50 whole adult skulls in Indian ethnic group. The depth of optic canal and sphenoid ridge from the pterion was recorded bilaterally in fifty cut adult skulls and fifteen three-dimensional computed tomography scans. The suture length, thickness, and morphology were studied. The data were analyzed using SPSS software, two-tailed Student's t test, binary logistic regression and receiver operating characteristic curve for sexual dimorphism. The pterion center was located at a mean distance of 37.02 mm above the midpoint of zygomatic arch, 28.20 mm behind the posterolateral margin of frontozygomatic suture, 42.73 mm lateral to the optic canal and 10.59 mm from the sphenoid ridge. The location did not exhibit sexual dimorphism. In 20% cases the pterion center was 40 mm or more above the midpoint of the zygomatic arch and in 5% cases 35 mm or more posterior to the posterolateral margin of frontozygomatic suture. The mean suture length was 10±3 mm. The mean thickness at the center of the pterion was 3.52±1.45 mm. The commonest variety was sphenoparietal followed by frontotemporal, epipteric, and stellate types. A thorough knowledge of these dimensions has innumerable neurosurgical implications in resection of sellar, parasellar, and paraclinoid tumors and circulatory aneurysms.

The metopic-sagittal craniosynostosis-report of 35 operative cases

PURPOSE

We have diagnosed 35 cases of the supposedly rare condition metopic-sagittal synostosis in the past 20 years. Here, we introduce their clinical symptoms, neuroradiological findings, and surgical treatment methods, as well as discuss the relevant literature.

METHODS

Subjects included 35 patients (33 boys and 2 girls; mean age 4.2 years; range 1-8 years). Magnetic resonance imaging (MRI) confirmed that there were no abnormal findings in the brain. Thirty patients presented with symptoms including speech delay, hyperactivity, autistic tendency, motor impairment, self-mutilation, and panic/temper tantrum behaviors. No other congenital malformation was observed, and all cases were considered to be the non-syndromic type. The final diagnosis was made using three-dimensional computed tomography (3D-CT) scans. The surgery was done the fronto-orbital advancement in addition to remove the large parts of sphenoid bones including sphenoid ridges at the skull base and trimmed the calvarium as necessary to reduce pressure.

RESULTS

Surgical intervention improved clinical symptoms in nearly all 35 patients; cosmetic problems in patients with scaphocephaly were also corrected.

CONCLUSIONS

In the cases of child patients with metopic-sagittal synostosis who had clinical symptoms, surgical intervention improved such symptoms, suggesting its potential utility for metopic-sagittal synostosis with clinical symptoms. A surgical procedure focusing on the skull base was important for our successes. Based on the fact that metopic-sagittal synostosis was diagnosed in 35 patients at one institution over a relatively short period of time, this pathological condition may not be as rare as is currently believed.