Percutaneous transluminal angioplasty in a patient with internal carotid artery stenosis following gamma knife radiosurgery for recurrent pituitary adenoma

Gamma Knife Radiosurgery for Indirect Dural Carotid-Cavernous Fistula: Long-Term Ophthalmological Outcome

Objective: The leading treatment option for dural carotid−cavernous sinus fistula is an endovascular approach with immediate improvement. Alternatively, radiosurgery is a slow response for obliterating the fistula and poses a radiation risk to the optic apparatus and the associated cranial nerves and blood vessels. In this study, we retrieved cases from a prospective database to assess the ophthalmological outcomes and complications in treating dural carotid cavernous sinus fistula with gamma knife radiosurgery (GKRS). Material and Methods: We retrieved a total of 65 cases of carotid cavernous sinus fistula treated with GKRS with margin dose of 18−20 Gy from 2003 to 2018 and reviewed the ophthalmological records required for our assessment. Results: The mean target volume was 2 ± 1.43 cc. The onset of symptom alleviated after GKRS was 3.71 ± 7.68 months. There were two cases with residual chemosis, two with cataract, two with infarction, one with transient optic neuropathy, and four with residual cranial nerve palsy, but none with glaucoma or dry eyes. In MRA analysis, total obliteration of the fistula was noted in 64 cases with no detectable ICA stenosis nor cavernous sinus thrombosis. In the Cox regression analysis, post-GKRS residual cranial nerve palsy was highly correlated to targeted volume (p < 0.05) and age (p < 0.05). The occurrence of post-GKRS cataract was related to the initial symptom of chemosis (p < 0.05). Conclusion: GKRS for carotid cavernous sinus fistula offers a high obliteration rate and preserves the cavernous sinus vascular structure while conferring a low risk of treatment complications such as adverse radiation risk to the optic apparatus and adjacent cranial nerves.

Internal carotid artery stenosis and risk of cerebrovascular ischemia following stereotactic radiosurgery for recurrent or residual pituitary adenomas

PURPOSE

To evaluate the incidence of internal carotid artery (ICA) stenosis and cerebrovascular accident in a series of patients treated with stereotactic radiosurgery (SRS) for recurrent or residual pituitary adenoma.

METHODS

All patients treated with single fraction SRS in our institution for recurrent or residual non-functioning-, growth hormone- and ACTH-secreting pituitary adenomas were retrospectively identified and reviewed. A comprehensive literature review to identify studies reporting on ICA steno-occlusive disease following SRS for pituitary adenomas and compare the risks of carotid stenosis and ischemic stroke in the SRS treated group to the general population figures.

RESULTS

528 patients [312 women and 216 men; median age at SRS 46 years old (range 12-80 years)] treated with SRS at our institution met study inclusion criteria. Mean clinical and radiologic follow-ups were 68.87 (SD ± 43.29) and 55.99 months (SD ± 38.03), respectively, and there were no clinically evident cerebral ischemic events noted. Asymptomatic, post-SRS, ICA stenosis occurred in two patients. A total of eight patients with ICA steno-occlusive disease following pituitary adenoma radiosurgery have been reported. Two of them suffered from ischemic stroke with however excellent recovery.

CONCLUSION

As compared to the general population, SRS for pituitary adenomas does not seem to confer appreciable increased risk for ICA steno-occlusive disease and ischemic stroke. However, post-SRS radiation vessel injuries do occur and physicians should be aware about this rare event. Prompt identification and management according to current guidelines are essential to prevent ischemic strokes.

Risk of internal carotid artery stenosis or occlusion after single-fraction radiosurgery for benign parasellar tumors

OBJECTIVE

Stereotactic radiosurgery (SRS) is an accepted treatment option for patients with benign parasellar tumors. Here, the authors' objective was to determine the risk of developing new or progressive internal carotid artery (ICA) stenosis or occlusion after single-fraction SRS for cavernous sinus meningioma (CSM) or growth hormone-secreting pituitary adenoma (GHPA).

METHODS

The authors queried their prospectively maintained registry for patients treated with single-fraction SRS for CSM or GHPA in the period from 1990 to 2015. Study criteria included no prior irradiation and ≥ 12 months of post-SRS radiological follow-up. Pre-SRS grading of ICA involvement was applied according to the 1993 classification schemes of Hirsch for CSM or Knosp for GHPA.

RESULTS

The authors conducted a retrospective review of 283 patients, 155 with CSMs and 128 with GHPAs. Ninety-three (60%) CSMs were Hirsch category 2 and 3 tumors; 97 (76%) GHPAs were Knosp grade 2-4 tumors. Median follow-up after SRS was 6.6 years (IQR 1-24.9 years). No GHPA or category 1 CSM developed ICA stenosis or occlusion. Three (5.2%) patients with category 2 CSMs had asymptomatic ICA stenosis (n = 2) or occlusion (n = 1); 1 (1.1%) category 2 CSM patient had transient ischemic symptoms. Five (14.3%) category 3 CSMs progressed to ICA occlusion (4 asymptomatic, 1 symptomatic). The median time to stenosis/occlusion was 4.8 years (IQR 1.8-7.6). Five- and 10-year risks of ICA stenosis/occlusion in category 2 and 3 CSM patients were 7.5% and 12.4%, respectively. Five- and 10-year risks of ischemic stroke from ICA stenosis/occlusion in category 2 and 3 CSM patients were both 1.2%. Multivariate analysis showed patient age (HR 0.92, 95% CI 0.86-0.98, p = 0.01), meningioma pathology (HR and 95% CI not defined, p = 0.03), and pre-SRS carotid category (HR 4.51, 95% CI 1.77-14.61, p = 0.004) to be associated with ICA stenosis/occlusion. Internal carotid artery stenosis/occlusion was not related to post-SRS tumor growth (HR and 95% CI not defined, p = 0.41).

CONCLUSIONS

New or progressive ICA stenosis/occlusion was common after SRS for CSM but was not observed after SRS for GHPA, suggesting a tumor-specific mechanism unrelated to radiation dose. Pre-SRS ICA encasement or constriction increases the risk of ICA stenosis/occlusion; however, the risk of ischemic complications is very low.

Cavernous carotid stenosis following stereotactic radiosurgery for Cushing's disease: A rare complication and review of the literature

Intracranial carotid stenosis or occlusion after SRS is an extraordinarily rare event. Because of the rarity of this event, increased awareness within the neurosurgical community is required. For those with post-radiosurgical carotid stenosis who are asymptomatic, longitudinal follow up is recommended. Management depends on whether the patient is symptomatic or asymptomatic. Those who are symptomatic may require balloon angioplasty, stenting, or bypass surgery.

Impact of optic canal decompression on visual outcome in subtotal resected skull base meningiomas

BACKGROUND

Visual impairment (VI) due to neoplastic infiltration of the optic canal (OC) is frequently seen in skull base meningiomas representing a significant restriction in patients` quality of life. However, the delicate anatomy of this region often prevents gross total tumor resection. The aim of the present study was to evaluate the impact of intradural OC decompression and postoperative oncological procedure on preservation of visual acuity in subtotal resected skull base meningiomas.

METHODS

A retrospective analysis of 31 consecutive patients (19 females, 12 males; mean age 53 [range 18-78]), treated in our institution between 01/2011- 09/2014 was performed. Patients` charts were analyzed with special respect to operative procedure, postoperative treatment and procedural impact on late visual function.

RESULTS

Most patients (74.2%) had VI prior to surgery. A pterional craniotomy (97%) facilitated subtotal tumor removal in 71% of the patients with no intraoperative and a low rate (6.4%) of postoperative complications. Adjunctive radiotherapy was performed in 19.3% of the patients. Preoperative visual acuity was preserved or improved in 92% of the patients. Substantial tumor regrowth occurred in only 11.2% of the patients.

CONCLUSIONS

Intradural decompression of the OC stabilizes visual function in subtotally resected skull base meningiomas. Moreover, adjuvant radiotherapy seems to further benefit visual outcome which has to be evaluated in further prospective studies.

Asymptomatic internal carotid artery occlusion after gamma knife radiosurgery for pituitary adenoma: Report of two cases and review of the literature

BACKGROUND

Gamma knife radiosurgery is an effective and safe treatment modality in the management of pituitary adenomas. Internal carotid occlusion is a rare but possible complication of Gamma Knife Radiosurgery for lesions within the cavernous sinus.

AIM

To stress the importance of considering the Internal carotid artery as an organ at risk in cavernous sinus invading adenomas and reduce the dose delivered to this structure whenever possible.

CASE DESCRIPTION

We report two cases of asymptomatic occlusion of the intracavernous segment of the internal carotid artery seven years after treatment in acromegalic patients. After trans-sphenoidal surgery, residual tumour was treated with gamma knife radiosurgery. The maximal doses to the affected artery were higher than 40 Gy and the 90% isodose was close to the arterial wall.

CONCLUSION

Every effort should be done to minimize the radiation dose to the internal carotid artery. If not possible, "hot spots" exceeding the 90% isodose close to this vessel should be avoided.