Cerebrovascular complications and utilization of endovascular techniques following transsphenoidal resection of pituitary adenomas: a study of the Nationwide Inpatient Sample 2001-2010

Vascular anomalies in patients with growth hormone-secreting pituitary adenomas: illustrative case report and systematic review of the literature

PURPOSE

Endonasal resection is the first-line treatment for patients harboring growth hormone (GH)-secreting pituitary adenomas. The complexity of the parasellar neurovascular structures makes pre-operative diagnostic imaging essential to understanding the anatomy of this region. We aimed to describe vascular anomalies in acromegalic patients and emphasize their relevance for surgery and preoperative planning.

METHODS

A systematic review following the PRISMA statement was performed in July 2021.

RESULTS

Thirty-three studies were evaluated. Elevated GH and insulin-like growth factor-1 (IGF-1) levels are linked to the occurrence of cardiovascular risk factors. This is attributed to endothelial dysfunction, mainly caused by changes in flow-mediated dilatation (FMD), which is probably the main cause of vascular anomalies in acromegaly. The occurrence of protrusions of the internal carotid artery (ICA) (35-53%), a narrow intercarotid distance, and an asymmetrical course was described. In 13-18% of acromegalic patients, the presence of an intracerebral aneurysm could be reported (incidence in the general population:0.8-1.3%). The selected studies were however performed with a small patient sample (range:1-257). We present a case report of a 57y/o male patient with anomalies of the ICA ("kissing carotid arteries") harboring a GH-secreting adenoma, which was resected via an endoscopic endonasal approach.

CONCLUSIONS

There is an association between acromegaly and endothelial dysfunction, which increases cardiovascular risk factors and vascular anomalies. Preoperative vascular imaging, e.g., CT angiography, should be implemented as a standard to identify patients at risk and estimate surgical morbidity. However, no evidence-based recommendations exist so far, so future studies are necessary.

The Shape grading system: a classification for growth patterns of pituitary adenomas

BACKGROUND

Long-term tumor control of pituitary adenomas may be achieved by gross total resection (GTR). Factors, which influence the extent of resection, are invasiveness, tumor size, and possibly tumor shape. Nevertheless, the latter factor has not been assessed so far and there is no classification for the different shapes. The aim of this study was to evaluate the impact of different tumor shapes on GTR rates and outcome according to our proposed "Shape grading system."

METHODS

In this retrospective single center study, the radiological outcome of nonfunctioning pituitary adenomas was assessed with respect to the following previously defined growth patterns: spherical (Shape I), oval (Shape II), dumbbell (Shape III), mushroom (Shape IV), and polylobulated (Shape V).

RESULTS

A total of 191 patients were included (Shape I, n = 28 (15%); Shape II, n = 91 (48%); Shape III, n = 37 (19%); Shape IV, n = 12 (6%); Shape V, n = 23 (12%)). GTR was achieved in 101 patients (53%) with decreasing likelihood of GTR in higher shape grades (Shape I, n = 23 (82%); Shape II, n = 67 (74%); Shape III, n = 9 (24%); Shape IV, n = 2 (17%); Shape V, n = 0 (0%)). This correlated with larger tumor remnants, a higher risk of tumor recurrence/regrowth and therefore necessity of re-surgery and/or radiotherapy/radiosurgery.

CONCLUSION

The "Shape grading system" may be used as a predictor of the outcome in nonfunctioning pituitary adenomas. The higher the "Shape grade," the higher the likelihood for lower GTR rates, larger tumor remnants, and need for further therapies.

Management of Noncatastrophic Internal Carotid Artery Injury in Endoscopic Skull Base Surgery

Arterial injuries are the most feared complication of endoscopic skull base surgery. During resection of the middle fossa component of a large ventral skull base chondrosarcoma, arterial bleeding was encountered near the right internal carotid artery (ICA). Durable hemostasis could not be achieved with packing and the patient was taken for an emergent angiogram that revealed a pseudoaneurysm of the proximal intradural ICA. Given the presence of good collateral flow through the anterior and posterior communicating arteries, the right ICA was sacrificed by coil embolization. The patient was taken back to the operating room for closure then transferred to the intensive care unit and maintained on vasopressors for five days to ensure adequate perfusion. The right ICA was coil embolized and the patient was taken back to the operating room for closure. The patient recovered without complication. Arterial injuries, although serious, are not always catastrophic. Critical steps are immediate recognition of bleeding, vascular imaging, and vessel sacrifice if necessary.

Carotid Artery Injury during Transsphenoidal Pituitary Surgery: Lessons from a 15-Year Modern Microsurgery Cohort

Background  Internal carotid artery (ICA) injury is a rare but potentially catastrophic complication of transsphenoidal resection (TSR) of pituitary tumors, potentially resulting in a host of deficits due to the risk of hemorrhage, ischemia, or even death. The endoscopic endonasal approach (EEA) has gained considerable popularity in the modern era, with few busy neurosurgeons remaining committed to practicing transnasal pituitary microsurgery. Our objective was therefore to characterize the overall incidence of ICA injury in a large, longitudinal, single-surgeon microscopic TSR series conducted during the modern EEA era. Methods  Retrospective case series. Results  Overall TSR volume by the senior author (F.B.M.) was 817 pituitary tumors during the study period, 2002 to 2017. Within that cohort, two instances of ICA injury were identified (0.2%), including one each with Cushing's disease and acromegaly, both of whom ultimately recovered without residual neurologic deficit. No pediatric injuries were identified. Conclusion  Vascular injury is an exceedingly rare complication of transsphenoidal pituitary surgery. Adjuncts to prevent this complication include careful review of the coronal magnetic resonance imaging, identification of the midline, as needed use of the Doppler, and initial caudal opening of the sellar dura. Although potentially disastrous, good neurologic outcomes may be obtained, with immediate judicious packing followed by immediate digital subtraction angiography to assess vessel patency and secondary complications such as pseudoaneurysm.

Managing Arterial Injury in Endoscopic Skull Base Surgery: Case Series and Review of the Literature

BACKGROUND

The most feared complications following endoscopic endonasal skull base surgery are arterial vascular injuries. Previously published literature is restricted to internal carotid artery injuries. The ideal method for controlling arterial bleeding during this kind of procedure is debated, and a variety of techniques have been advocated.

OBJECTIVE

To evaluate the management and outcome following intraoperative arterial injury during endoscopic endonasal skull base surgery.

METHODS

We performed a retrospective review of a prospectively acquired database of consecutive endonasal endoscopic surgeries at the New York-Presbyterian Hospital/Weill Cornell Medical Center from December 2003 to June 2015 and identified all cases of arterial injury.

RESULTS

Of 800 cases, there were 4 arterial injuries (0.5%), of which only one involved the internal carotid artery (ICA), for a risk of 0.125%. The other 3 involved the ophthalmic artery, anterior communicating artery, and A1 segment of the anterior cerebral artery. In all cases, definitive treatment involved occlusion of the artery either through endovascular means (3 cases) or direct surgical ligation (1 case). Neurological examinations were unchanged after arterial repair with only 1 small asymptomatic stroke. Literature review identified 7336 patients, of which there were 25 arterial injuries, of which 19 were of the ICA. Hence, the total rate of arterial injury was 0.34% and the rate of ICA injury was 0.26%. Arterial sacrifice was the only reliable method for managing arterial injury.

CONCLUSION

Arterial injury is an uncommon event after endoscopic endonasal surgery. Attempts at arterial repair are rarely successful, and vessel sacrifice is the most reliable technique at this point.

Comparison of Complications, Trends, and Costs in Endoscopic vs Microscopic Pituitary Surgery: Analysis From a US Health Claims Database

BACKGROUND

Microsurgical and endoscopic techniques are commonly utilized surgical approaches to pituitary pathologies. There are limited data comparing these 2 procedures.

OBJECTIVE

To evaluate postoperative complications, associated costs, and national and regional trends of microscopic and endoscopic techniques in the United States employing a nationwide database.

METHODS

The Truven MarketScan database 2010 to 2014 was queried and Current Procedural Terminology codes identified patients that underwent microscopic and/or endoscopic transsphenoidal pituitary surgery. International Classification of Diseases codes identified postoperative complications. Adjusted logistic regression and matched propensity analysis evaluated independent odds for complications.

RESULTS

Among 5886 cases studied, 54.49% were microscopic and 45.51% endoscopic. The commonest surgical indications were benign pituitary tumors. Annual trends showed increasing utilization of endoscopic techniques vs microscopic procedures. Postoperative complications occurred in 40.04% of cases, including diabetes insipidus (DI; 16.90%), syndrome of inappropriate antidiuretic hormone (SIADH; 2.02%), iatrogenic hypopituitarism (1.36%), fluid/electrolyte abnormalities (hypoosmolality/hyponatraemia [5.03%] and hyperosmolality/hypernatraemia [2.48%]), and cerebrospinal fluid (CSF) leaks (CSF rhinorrhoea [4.42%] and other CSF leak [6.52%]). In our propensity-based model, patients that underwent endoscopic surgery were more likely to develop DI (odds ratio [OR] = 1.48; 95% confidence interval [CI] = 1.28-1.72), SIADH (OR = 1.53; 95% CI = 1.04-2.24), hypoosmolality/hyponatraemia (OR = 1.17; 95% CI = 1.01-1.34), CSF rhinorrhoea (OR = 2.48; 95% CI = 1.88-3.28), other CSF leak (OR = 1.59; 95% CI = 1.28-1.98), altered mental status (OR = 1.46; 95% CI = 1.01-2.60), and postoperative fever (OR = 4.31; 95% CI = 1.14-16.23). There were no differences in hemorrhagic complications, ophthalmological complications, or bacterial meningitis. Postoperative complications resulted in longer hospitalization and increased healthcare costs.

CONCLUSION

Endoscopic approaches are increasingly being utilized to manage sellar pathologies relative to microsurgery. Postoperative complications occur in both techniques with higher incidences observed following endoscopic procedures.

Rapid intraoperative histology of unprocessed surgical specimens via fibre-laser-based stimulated Raman scattering microscopy

Conventional methods for intraoperative histopathologic diagnosis are labour- and time-intensive, and may delay decision-making during brain-tumour surgery. Stimulated Raman scattering (SRS) microscopy, a label-free optical process, has been shown to rapidly detect brain-tumour infiltration in fresh, unprocessed human tissues. Here, we demonstrate the first application of SRS microscopy in the operating room by using a portable fibre-laser-based microscope and unprocessed specimens from 101 neurosurgical patients. We also introduce an image-processing method – stimulated Raman histology (SRH) – which leverages SRS images to create virtual haematoxylin-and-eosin-stained slides, revealing essential diagnostic features. In a simulation of intraoperative pathologic consultation in 30 patients, we found a remarkable concordance of SRH and conventional histology for predicting diagnosis (Cohen's kappa, κ > 0.89), with accuracy exceeding 92%. We also built and validated a multilayer perceptron based on quantified SRH image attributes that predicts brain-tumour subtype with 90% accuracy. Our findings provide insight into how SRH can now be used to improve the surgical care of brain tumour patients.

Effect of Center Volume on Outcomes in Hospitalized Patients With Hereditary Hemorrhagic Telangiectasia

OBJECTIVE

To determine whether hospitalized patients with hereditary hemorrhagic telangiectasia (HHT) had better outcomes at high-volume treatment centers (HVCs).

PATIENTS AND METHODS

The Nationwide Inpatient Sample (2000-2011) was used to identify HHT-related hospitalizations. Hospitals were classified based on quartiles of annual HHT discharge volume. The 75th percentile cutoff value (third quartile) was used to classify hospitals as low-volume centers (1-7 HHT discharges per year) or as HVCs (≥8 discharges per year. Demographic features, complication rates, and outcomes were compared between the 2 groups.

RESULTS

We identified 9440 hospital discharges in patients with HHT. Of these patients, 6856 (72.6%) were admitted to low-volume centers and 2584 (27.4%) to HVCs. The former were more likely to be of white race, older, and with higher income levels (P<.001 for each). The HVCs had higher rates of anemia, epistaxis, congestive heart failure, pulmonary hypertension, and cerebral and pulmonary arteriovenous malformations and lower rates of ischemic stroke and myocardial infarction. After adjusting for baseline differences in a multivariate model, patients treated at HVCs were more likely to be discharged home (odds ratio [OR]=1.35; 95% CI, 1.21-1.52; P<.001) and less likely to be discharged to short-term rehabilitation facilities (OR=0.45; 95% CI, 0.31-0.64; P<.001). Patients treated at HVCs also had a significantly lower risk of in-hospital mortality (OR=0.51; 95% CI, 0.34-0.74; P<.001).

CONCLUSION

Patients with HHT hospitalized at HVCs had better outcomes, with lower in-hospital mortality and higher home discharge rates. These findings strongly support ongoing efforts to expand access to HHT centers of excellence in the United States and worldwide.

Endovascular management of internal carotid artery injuries secondary to endonasal surgery: case series and review of the literature

OBJECTIVE Internal carotid artery (ICA) injury is a rare but severe complication of endonasal surgery. The authors describe their endovascular experience managing ICA injuries after transsphenoidal surgery; they review and summarize the current literature regarding endovascular techniques; and they propose a treatment algorithm based on the available evidence. METHODS A retrospective review of 576 transsphenoidal pituitary adenoma resections was performed. Cases of ICA injury occurring at our institution and transfers from other hospitals were evaluated. Endovascular treatments for ICA injury reported in the literature were also reviewed and summarized. RESULTS Seven cases were identified from the institutional cohort (mean age 46.3 years, mean follow-up 43.4 months [1-107 months]) that received endovascular treatment for ICA injury. Five injuries occurred at our institution (5 [0.9%] of 576), and 2 injuries occurred at outside hospitals. Three patients underwent ICA sacrifice by coil placement, 2 underwent lesion embolization (coil or stent-assisted coil placement), and 2 underwent endoluminal reconstruction (both with flow diversion devices). Review of the literature identified 98 cases of ICA injury treated with endovascular methods. Of the 105 total cases, 46 patients underwent ICA sacrifice, 28 underwent lesion embolization, and 31 underwent endoluminal reconstruction. Sacrifice of the ICA proved a durable solution in all cases; however, the rate of persistent neurological complications was relatively high (10 [21.7%] of 46). Lesion embolization was primarily performed by coil embolization without stenting (16 cases) and stent-assisted coiling (9 cases). Both techniques had a relatively high rate of at least some technical complication (6 [37.5%] of 16 and 5 [55.6%] of 9, respectively) and major technical complications (i.e., injury, new neurological deficit, or ICA sacrifice) (5 [31.3%] of 16 and 2 [22.2%] of 9, respectively). Endoluminal reconstruction was performed by covered stent (24 cases) and flow diverter (5 cases) placement. Covered stents showed a reasonably high rate of technical complications (10 [41.7%] of 24); however, 8 of these problems were resolved, leaving a small percentage with major technical complications (2 [8.3%] of 24). Flow diverter placement was also well tolerated, with only 1 minor technical complication. CONCLUSIONS Endovascular treatments including vessel sacrifice, coil embolization (with or without stent assistance), and endoluminal reconstruction offer a tailored approach to ICA injury management after endonasal surgery. Vessel sacrifice remains the definitive treatment for acute, uncontrolled bleeding; however, vessel preservation techniques should be considered carefully in select patients. Multiple factors including vascular anatomy, injury characteristics, and risk of dual antiplatelet therapy should guide best treatment, but more study is needed (particularly with flow diverters) to refine this decision-making process. Ideally, all endovascular treatment options should be available at institutions performing endonasal surgery.