Robert M. Starke, Felipe C. Albuquerque and Michael T. Lawton
It is with great pleasure that we present this Neurosurgical Focus video supplement on supratentorial cerebral arteriovenous malformations (AVMs). We were privileged to view a remarkable number of outstanding videos demonstrating current state-of-the-art management of brain AVMs using endovascular and microsurgical modalities. Careful and critical review was required to narrow down the submitted videos to a workable volume for this supplement, which reflects the excellent work being done at multiple centers with these lesions.
This issue consists of videos that represent modern microsurgical and neuroendovascular techniques for the treatment of supratentorial cerebral AVMs. The videos demonstrate cutting-edge therapies as well as standard ones, which will be valuable to both novice and expert neurointerventionists and neurosurgeons. We are honored to be involved with this project and proud of its content and expert authors. We believe you will enjoy the video content of this supplement and hope that it will raise the collective expertise of our community of AVM surgeons.
Lucia Schwyzer, Robert M. Starke, John A. Jane Jr. and Edward H. Oldfield
Correlation between tumor volume and hormone levels in individual patients would permit calculation of the fraction of tumor removed by surgery, by measuring postoperative hormone levels. The goals of this study were to examine the relationship between tumor volume, growth hormone (GH), and insulin-like growth factor–1 (IGF-1) levels, and to assess the correlation between percent tumor removal and the reduction in plasma GH and IGF-1 in patients with acromegaly.
The 3D region of interest–based volumetric method was used to measure tumor volume via MRI before and after surgery in 11 patients with GH-secreting adenomas. The volume of residual tumor as a fraction of preoperative tumor volume was correlated with GH levels before and after surgery. Examination of this potential correlation required selection of patients with acromegaly who 1) had incomplete tumor removal, 2) had precise measurements of initial and residual tumor, and 3) were not on medical therapy.
Densely granulated tumors produced more peripheral GH per mass of tumor than sparsely granulated tumors (p = 0.04). There was a correlation between GH and IGF-1 levels (p = 0.001). Although there was no close correlation between tumor size and peripheral GH levels, after normalizing each tumor to its own plasma GH level and tumor volume, a comparison of percent tumor resection with percent drop in plasma GH yielded a high correlation coefficient (p = 0.006).
Densely granulated somatotropinomas produce more GH per mass of tumor than do sparsely granulated tumors. Each GH-secreting tumor has its own intrinsic level of GH production per mass of tumor, which is homogeneous over the tumor mass, and which varies greatly between tumors. In most patients the fraction of a GH-secreting tumor removed by surgery can be accurately estimated by simply comparing plasma GH levels after surgery to those before surgery.
Robert M. Starke, Ricardo J. Komotar and E. Sander Connolly
Moyamoya disease is a chronic cerebrovascular occlusive disorder that results in severe morbidity and death. There is much controversy surrounding the optimal treatment for adult patients with the disorder. There have been no randomized trials to assess the efficacy of any single surgical treatment, and existing case series suffer from inadequate power, selection bias, and inherent differences in patient characteristics. In this article the authors review the literature concerning the optimal surgical treatment of adult patients with moyamoya disease.
Robert Michael Starke
Robert M. Starke, John A. Jane Jr., Ashok R. Asthagiri and John A. Jane Sr.
Badih Daou, Christine Hammer, Nohra Chalouhi, Robert M. Starke, Pascal Jabbour, Robert H. Rosenwasser and Stavropoula Tjoumakaris
Dissection of the carotid and vertebral arteries can result in the development of aneurysmal dilations. These dissecting pseudoaneurysms can enlarge and cause symptoms. The objective of this study is to provide insight into the progression of dissecting pseudoaneurysms and the treatments required to manage them.
A review of the electronic medical records was conducted to detect patients with carotid and vertebral artery dissection. An imaging review was conducted to identify patients with dissecting pseudoaneurysms. One hundred twelve patients with 120 dissecting pseudoaneurysms were identified. Univariate and multivariate analyses were conducted to assess the factors associated with undergoing further interventions other than medical treatment, pseudoaneurysm enlargement, pseudoaneurysms resulting in ischemic and nonischemic symptoms, and clinical outcome.
Overall, 18.3% of pseudoaneurysms were intracranial and 81.7% were extracranial, and the average size was 7.3 mm. The mean follow-up time was 29.3 months; 3.3% of patients had a recurrent transient ischemic attack, no patients had a recurrent stroke, and 14.2% of patients had recurrence of nonischemic symptoms (headache, neck pain, Horner syndrome, or cranial nerve palsy). Follow-up imaging demonstrated that 13.8% of pseudoaneurysms had enlarged, 30.2% had healed, and 56% had remained stable. In total, 20.8% of patients had an intervention other than medical treatment. Interventions included stenting, coiling, flow diversion, and clipping. Predictors of intervention included increasing size, size > 10 mm, location in the C2 (petrous) segment of the internal carotid artery (ICA), younger age, hyperlipidemia, pseudoaneurysm enlargement, and any symptom development. Significant predictors of enlargement included smoking, history of trauma, C2 location, hyperlipidemia, and larger initial pseudoaneurysm size. Predictors of pseudoaneurysm resulting in recurrent ischemic and nonischemic symptoms included increasing size and location in the petrous segment of the ICA. Smoking was a predictor of unfavorable outcome.
Dissecting pseudoaneurysms have a benign course and most will not cause symptoms or enlarge on follow-up. Medical treatment can be a sufficient, initial treatment for dissecting pseudoaneurysms.
Jason Sheehan, Dale Ding and Robert M. Starke
Allan D. Levi, Robert M. Starke, Ricardo J. Komotar and Robert E. Harbaugh
Robert M. Starke, Justin M. Cappuzzo, Nicholas J. Erickson and Jonathan H. Sherman
Cystic lesions of the pineal gland are most often uncomplicated benign lesions with typical MRI characteristics. The authors aimed to study pineal lesion characteristics on MRI to better distinguish benign pineal cysts from other pineal region malignancies as well as to determine which characteristics were predictive of the latter malignancies. They also aimed to study risk factors predictive of hydrocephalus or malignancy in patients harboring these lesions.
The authors performed a retrospective review of a prospectively compiled database documenting the outcomes of patients with suspected pineal cysts on MRI who had presented in the period from 1998 to 2004. Inherent patient and lesion characteristics were assessed in a univariate logistic regression analysis to predict the following dependent variables: development of hydrocephalus, biopsy-confirmed malignancy, and intervention. Possible inherent patient and lesion characteristics included age, sex, T1 and T2 MRI signal pattern, contrast enhancement pattern, presence of cyst, presence of blood, complexity of lesion, presence of calcification, and duration of follow-up. Inherent patient and lesion characteristics that were predictive in the univariate analysis (p < 0.15) were included in the multivariable logistic regression analysis.
Of the 79 patients with benign-appearing pineal cysts, 26 (33%) were male and 53 (67%) were female, with a median age of 38 years (range 9–86 years). The median cyst radius was 5 mm (range 1–20 mm). Two patients (2.5%) had evidence of calcifications, 7 (9%) had multicystic lesions, and 25 (32%) had some evidence of contrast enhancement.
The median follow-up interval was 3 years (range 0.5–13 years). Seven patients (9%) had an increase in the size of their lesion over time. Eight patients (10%) had a hemorrhage, and 11 patients (14%) developed hydrocephalus. Nine (11%) received ventriculoperitoneal shunts for the development of hydrocephalus, and 12 patients (16%) were found to have malignancies following biopsy or resection. In the multivariate analysis, contrast enhancement on MRI (OR 1.6, 95% CI 2.86–74.74, p = 0.013) and hemorrhage (OR 26.9, 95% CI 3.4–212.7, p = 0.022) were predictive of hydrocephalus. Increasing lesion size and hydrocephalus were near perfect predictors of malignancy and thus were removed from multivariate analysis. In addition, contrast enhancement on MRI (OR 8.8, 95% CI 2.0–38.6, p = 0.004) and hemorrhage (OR 6.8, 95% CI 1.1–40.5, p = 0.036) were predictive of malignancy.
Although cystic abnormalities of the pineal gland are often benign lesions, they are frequently monitored over time, as other pineal region pathologies may appear similarly on MRI. Patients with growing lesions, contrast enhancement, and hemorrhage on MRI are more likely to develop hydrocephalus and have malignant pathology on histological examination and should therefore be followed up with serial MRI with a lower threshold for neurosurgical intervention.