Carlo Bortolotti and Carmelo Sturiale
Carlo Bortolotti, Huan Wang, Kenneth Fraser, and Giuseppe Lanzino
✓ The etiopathogenesis of traumatic spinal subdural hematoma (SSH) is uncertain. Unlike the supratentorial subdural space, no bridging veins traverse the spinal subdural space. The authors describe a case of subacute SSH that occurred after spontaneous resolution of traumatic intracranial SDH and suggest a causal relationship between the two.
A 23-year-old woman suffered an acute intracranial SDH after a snowboarding accident. There was no clinical or radiological evidence of spine injury. Conservative management of the supratentorial SDH resulted in spontaneous radiologically documented resolution with redistribution of blood in the subdural space.
Four days after the injury, the patient started noticing new onset of mild low-back pain. The pain progressively worsened. Magnetic resonance imaging of the lumbosacral spine 10 days after the original injury revealed a large L4—S2 SDH. Ten days after the original injury, bilateral L5—S1 laminotomy and drainage of the subacute spinal SDH were performed. The patient experienced immediate pain relief.
The authors hypothesize that in some cases spinal SDH may be related to redistribution of blood from the supratentorial subdural space.
Robert R. Kraus, Jorge Kattah, Carlo Bortolotti, and Giuseppe Lanzino
✓ The authors describe a patient with an unruptured posterior communicating artery aneurysm presenting with enhancement of the third cranial nerve on magnetic resonance (MR) imaging and cerebrospinal fluid (CSF) pleocytosis. Pathological entities associated with enhancement of the third cranial nerve on MR imaging are discussed and the authors speculate about the possible explanation for the CSF pleocytosis.
Saul F. Morales-Valero, Carlo Bortolotti, Carmelo Sturiale, and Giuseppe Lanzino
A long-held dogma in neurosurgery is that parenchymal arteriovenous malformations (AVMs) are congenital. However, there is no strong evidence supporting this theory. An increasing number of documented cases of de novo formation of parenchymal AVMs cast doubt on their congenital nature and suggest that indeed the majority of these lesions may form after birth. Further evidence suggesting the postnatal development of parenchymal AVMs comes from the exceedingly rare diagnosis of these lesions in utero despite the widespread availability of high-resolution imaging modalities such as ultrasound and fetal MRI. The exact mechanism of AVM formation has yet to be elucidated, but most likely involves genetic susceptibility and environmental triggering factors. In this review, the authors report 2 cases of de novo AVM formation and analyze the evidence suggesting that they represent an acquired condition.
Marco Cenzato, Davide Colistra, Giorgia Iacopino, Christian Raftopoulos, Ulrich Sure, Marcos Tatagiba, Robert F. Spetzler, Alexander N. Konovalov, Andriy Smolanka, Volodymir Smolanka, Roberto Stefini, Carlo Bortolotti, Paolo Ferroli, Giampietro Pinna, Angelo Franzini, Philipp Dammann, Georgios Naros, Davide Boeris, Paolo Mantovani, Domenico Lizio, Mariangela Piano, and Enrica Fava
In this paper, the authors aimed to illustrate how Holmes tremor (HT) can occur as a delayed complication after brainstem cavernoma resection despite strict adherence to the safe entry zones (SEZs).
After operating on 2 patients with brainstem cavernoma at the Great Metropolitan Hospital Niguarda in Milan and noticing a similar pathological pattern postoperatively, the authors asked 10 different neurosurgery centers around the world to identify similar cases, and a total of 20 were gathered from among 1274 cases of brainstem cavernomas. They evaluated the tremor, cavernoma location, surgical approach, and SEZ for every case. For the 2 cases at their center, they also performed electromyographic and accelerometric recordings of the tremor and evaluated the post-operative tractographic representation of the neuronal pathways involved in the tremorigenesis. After gathering data on all 1274 brainstem cavernomas, they performed a statistical analysis to determine if the location of the cavernoma is a potential predicting factor for the onset of HT.
From the analysis of all 20 cases with HT, it emerged that this highly debilitating tremor can occur as a delayed complication in patients whose postoperative clinical course has been excellent and in whom surgical access has strictly adhered to the SEZs. Three of the patients were subsequently effectively treated with deep brain stimulation (DBS), which resulted in complete or almost complete tremor regression. From the statistical analysis of all 1274 brainstem cavernomas, it was determined that a cavernoma location in the midbrain was significantly associated with the onset of HT (p < 0.0005).
Despite strict adherence to SEZs, the use of intraoperative neurophysiological monitoring, and the immediate success of a resective surgery, HT, a severe neurological disorder, can occur as a delayed complication after resection of brainstem cavernomas. A cavernoma location in the midbrain is a significant predictive factor for the onset of HT. Further anatomical and neurophysiological studies will be necessary to find clues to prevent this complication.