Endoscopic endonasal transclival clipping of a cerebellar arteriovenous malformation feeding vessel and associated aneurysm; a 2D operative video

Positioned along the ventral surface of the pons, proximal superior cerebellar artery (SCA) aneurysms account for only 1.7% of all intracranial aneurysms [1]. Unlike more commonly encountered basilar artery aneurysms, patients often experience good outcomes when treated via endovascular coiling or surgical clipping [1,2]. These lesions frequently have a lateral projection and paucity of perforator arteries [2]. With further development of endoscopic endonasal techniques, access to this region is possible via a direct frontal exposure to the ventral brainstem, basilar artery and branching vessels. To date, there are only a limited number of reports describing an endoscopic endonasal transclival (EETC) approach for surgical clipping [3-5]. In this operative video, we detail the surgical clipping of a cerebellar arteriovenous malformation feeding vessel and an associated aneurysm using the EETC approach in a 59-year-old woman who presented with sudden onset of a severe headache. The feeding vessel and aneurysm's midline location, just below the take-off of the SCA made it a good candidate for this surgery. Major steps included in this video include 1) transsphenoidal exposure of and subsequent drilling of the clivus, 2) dural opening into the pre-pontine cistern and dissection of the aneurysm, 3) clipping of the aneurysm, and 4) multi-layered closure of the skull base defect. Overall, the patient tolerated the procedure well and was found to have no residual filling of the aneurysm or the AVM feeding vessel at 2-year follow-up. EETC is a viable surgical option for the treatment of aneurysm located along the midline of the pre-pontine cistern.

Spinal cord stimulation for genitofemoral neuropathy: A case report and review of the literature

Background:

Chronic testicular pain due to genitofemoral neuropathy often becomes refractory to conservative medical therapy. Neurostimulation is a potentially useful treatment option, should the neuropathic pain remain refractory to more invasive procedures such as orchiectomy. We provide a case report of spinal cord stimulation (SCS) for successful treatment of genitofemoral neuropathy and have also reviewed the literature to find similar cases which required a similar treatment paradigm.

Case Description:

A 42-year-old male underwent SCS for refractory testicular and groin pain. SCS through a four-column, 2 × 8 contact neurostimulator paddle lead, was implanted in the mid-thoracic-9 (T9) vertebral level, providing > 50% testicular pain relief with a decrease in visual analog scale scores from 8–10/10 to 3–4/10. The patient required one adjustment to the stimulation parameters at the time of the 6 weeks follow-up visit due to over-stimulation. He then continued to experience >50% resolution in pain 9 months later. A review of the literature yielded only two similar cases that successfully utilized SCS for treatment of chronic testicular pain.

Conclusion:

SCS should be considered as a possible treatment option for patients with chronic testicular pain localized to the genitofemoral nerve distribution.

Revascularization of the Posterior Inferior Cerebellar Artery Using the Occipital Artery: A Cadaveric Study Comparing the p3 and p1 Recipient Sites

BACKGROUND

Revascularization of the posterior inferior cerebellar artery (PICA) is typically performed with the occipital artery (OA) as an extracranial donor. The p3 segment is the most accessible recipient site for OA-PICA bypass at its caudal loop inferior to the cerebellar tonsil, but this site may be absent or hidden due to a high-riding location.

OBJECTIVE

To test our hypothesis that freeing p1 PICA from its origin, transposing the recipient into a shallower position, and performing OA-p1 PICA bypass with an end-to-end anastomosis would facilitate this bypass.

METHODS

The OA was harvested, and a far lateral craniotomy was performed in 16 cadaveric specimens. PICA caliber and number of perforators were measured at p1 and p3 segments. OA-p3 PICA end-to-side and OA-p1 PICA end-to-end bypasses were compared.

RESULTS

OA-p1 PICA bypass with end-to-end anastomosis was performed in 16 specimens; whereas, OA-p3 PICA bypass with end-to-side anastomosis was performed in 11. Mean distance from OA at the occipital groove to the anastomosis site was shorter for p1 than p3 segments (30.2 vs 48.5 mm; P < .001). Median number of perforators on p1 was 1, and on p3, it was 4 (P < .001).

CONCLUSION

Although most OA-PICA bypasses can be performed using the p3 segment as the recipient site for an end-to-side anastomosis, a more feasible alternative to conventional OA-p3 PICA bypass in cases of high-riding caudal loops or aberrant anatomy is to free the p1 PICA, transpose it away from the lower cranial nerves, and perform an end-to-end OA-p1 PICA bypass instead.