Domenico d'Avella and Salvatore Mingrino
✓ A dissecting microscope study of the microsurgical anatomy of the lumbosacral spinal roots, carried out on the spinal cords of 30 adult subjects, is reported. The longitudinal extent of the medullary segment of origin of each root, and the morphological features of the root-spinal cord junction are described. Observations regarding intrathecal anastomoses between anterior and posterior roots, and shape, position, and real incidence of anastomotic rami are reported. The authors emphasize the importance of anastomotic rami when performing a rhizotomy.
Domenico D'Avella, Rocco Cicciarello, Francesca Albiero, and Giancarlo Andrioli
✓ The functional morphology of human arachnoid villi obtained from surgical biopsy specimens has been studied by scanning electron microscopy (SEM). On SEM examination, the villi appeared to be distended, as if functioning normally. The endothelial cells constituting the cerebrospinal fluid (CSF)-blood interface were covered by numerous microvilli, uniformly oriented along the major axis of the villus. Examination for cell-to-cell contact revealed only occasional areas of tight adherence between adjacent endothelial cells, while widened intercellular spaces were frequently observed. Generally corresponding to the apex of the villus, points of emergence of endothelium-lined hollow structures were identified; these may represent apical openings of open pathways from the subarachnoid space to the venous system. Ultrastructural arrangements consistent with a closed system of CSF reabsorption were also observed. Large cells maximally distended and protruding into the sinus lumen were commonly seen; these were interpreted as the result of the formation of giant vacuoles within the endothelium covering the villus.
This study has provided ultrastructural evidence for both closed and open systems of CSF reabsorption. Ultrastructural findings, such as gaps between endothelial cells and tubule-like endothelium-lined structures as previously identified in animals and observed in man by transmission electron microscopy, were demonstrated in human biopsy specimens by SEM.
Pierluigi Longatti, Alessandro Fiorindi, Alberto Feletti, Domenico D'Avella, and Andrea Martinuzzi
Microsurgical anatomy of the fourth ventricle has been comprehensively addressed by masterly reports providing classic descriptions of this complex region. Neuroendoscopy could offer a new, somewhat different perspective of the “inside” view of the fourth ventricle. The purpose of this study was to examine from the anatomical point of view the access to the fourth ventricle achieved by the endoscopic transaqueductal approach, to enumerate and describe the anatomically identifiable landmarks, and to compare them with those described during microsurgery.
The video recordings of 52 of 75 endoscopic explorations of the fourth ventricle performed at the authors' institution for different pathological conditions were reviewed and evaluated to identify and describe every anatomical landmark. According to the microsurgical anatomy, at least 23 superficial structures are clearly identifiable in the fourth ventricle, and they represent the comparative basis of parallel endoscopic anatomy of the structures found during the fourth ventricle navigation.
The following anatomical structures were identified in all cases: median sulcus, superior and inferior vela medullare, choroid plexus, inferior fovea, hypoglossal and vagal triangles, area postrema, obex, canalis medullaris, lateral recess, and the foramina of Luschka and Magendie. The median eminence, facial colliculus, striae medullaris, auditory tubercle, and inferior fovea were seen in the majority of cases. The locus caevruleus could never be seen.
On the whole, 20 anatomical structures could consistently be identified by exploring the fourth ventricle with a fiberscope. Neuroendoscopy offers a quite different outlook on the anatomy of the fourth ventricle, and compared with the microsurgical descriptions it seems to provide a superior and detailed visualization, particularly of the structures located in the inferior triangle.
Domenico d'Avella, Maria Giusa, Alfredo Blandino, Filippo Flavio Angileri, Giovanni La Rosa, and Francesco Tomasello
✓ Solitary focal eosinophilic granuloma (EG) is one element in the spectrum of diseases associated with Langerhans' cell histiocytosis (LCH). This report documents the occurrence of a primary isolated hypothalamic EG in a man who presented with diabetes insipidus and panhypopituitarism. His treatment consisted of complete microsurgical excision of the lesion. After a 13-month follow-up period, no residual tumor was evident on magnetic resonance imaging and no other lesions were present in peripheral tissues. This case is unique in several respects: 1) it is the third documented case of a primary isolated hypothalamic LCH granuloma diagnosed in a living patient; 2) it is the only known example of complete microsurgical excision of such a lesion in the hypothalamic region; and 3) it demonstrates the efficacy of direct surgery in this scenario, as compared with other treatment modalities such as biopsy and irradiation, suggesting that complete surgical excision may represent the treatment of choice for isolated intracerebral LCH granulomas, being curative in most instances. Also, the literature is reviewed for information about the diagnosis and treatment of this particular type of unifocal brain lesion.
Alberto Feletti, Luca Denaro, Roberto Faggin, Pietro Ciccarino, Marta Rossetto, and Domenico d'Avella
Antonino Germanò, Claudia Imperatore, Domenico d'Avella, Giovanni Costa, and Francesco Tomasello
Object. The radical scavenger (±)-N,N′-propylenedinicotinamide (AVS) was shown recently to ameliorate delayed neurological deficits resulting from ischemia in patients who have had an aneurysmal subarachnoid hemorrhage (SAH). The aim of this study was to evaluate the effect of AVS administration after experimental SAH on 1) behavioral deficits; 2) angiographically confirmed basilar artery (BA) spasm; and 3) blood-brain barrier (BBB) permeability changes.
Methods. These parameters were measured by 1) using a battery of well-characterized chronic assessment tasks over a 5-day observation period; 2) assessing in vivo the mean vessel diameter 2 days after SAH; and 3) evaluating the extravasation of protein-bound Evans Blue dye by using a spectrophotofluorimetric technique 2 days after SAH. Groups of eight to 10 rats received injections of 400 µl of autologous blood into the cisterna magna. Within 5 minutes after the surgical procedures were completed the rats were treated with an intravenously administered continuous infusion of saline (Group III) or AVS (1 mg/kg/minutes, Group IV). Results were compared with those in sham-operated animals treated with intravenously administered saline (Group I) or AVS (Group II). The AVS-treated rats had significantly improved balance beam scores on Days 1 to 2 (p < 0.05), shorter beam traverse times on Day 1 (p < 0.05), and better beam walking performance on Days 1 to 4 (p < 0.01), but no significant effect was seen in terms of SAH-related changes in body weight. Treatment with AVS also attenuated the SAH-induced BA spasm (p < 0.05) and decreased BBB permeability changes in frontal, temporal, parietal, occipital, and cerebellar cortices, and in the subcortical and cerebellar gray matter and brainstem (p < 0.01).
Conclusions. These results demonstrate useful antivasospastic and brain-protective actions of AVS after induction of experimental SAH and provide support for observations of beneficial effects of AVS made in the clinical setting.
Massimo Scanarini, Domenico d'Avella, Antonino Rotilio, Nicolaos Kitromilis, and Salvatore Mingrino
✓ Idiopathic giant-cell granulomatous hypophysitis is a chronic inflammatory disorder of the pituitary gland. It presents clinically as a sellar mass lesion with pituitary insufficiency and/or hyperprolactinemia, and is radiologically indistinguishable from a pituitary tumor. In most of the previously reported cases the documentation of the disorder has been limited to autopsy tissue. Only a few cases documented by biopsy have been recorded. Four cases are presented here with radiological, endocrinological, and surgical findings. The appropriately documented cases collected from the literature and the present series are reviewed and the incidence, patterns of clinical and radiological presentation, and operative management of this disorder are discussed. This entity should be considered when evaluating patients with a pituitary mass and evidence of hypopituitarism and hyperprolactinemia.
Report of two cases
Domenico d'Avella, Francesco De Blasi, Antonino Rotilio, Vincenzo Pensabene, and Nicola Pandolfo
✓ Two cases of intracerebral hemorrhage occurring after evacuation of bilateral chronic subdural hematomas are reported. Possible pathogenic mechanisms included hemorrhage into previously undetected areas of contusion, damage to cerebral vasculature secondary to rapid perioperative parenchymal shift, and sudden increase in cerebral blood flow combined with focal disruption of autoregulation; of these, the latter mechanism seemed most likely to be responsible for the hematoma formation. The need for clinical awareness of this nearly uniformly devastating complication, as well as prompt use of computerized tomography scanning in assessing the postoperative course, are stressed.
Roberto Faggin, Milena Calderone, Luca Denaro, Luisa Meneghini, and Domenico d'Avella
Although a rarely reported occurrence, late failure of endoscopic third ventriculostomy (ETV) may occur in children as a result of a variety of factors. Delay in recognition of symptoms can lead to harmful deterioration in the patient's condition. The authors undertook this study to assess the capacity of cine phase-contrast MR imaging to identify late failure in asymptomatic pediatric patients treated with ETV for hydrocephalus.
This study was a retrospective evaluation of cases involving patients who underwent ETV between January 1, 1999, and December 31, 2008, at the pediatric neurological surgery service of the University of Padua. Before 2004, patients were routinely followed up with cine MR imaging at 3, 6, and 12 months after ETV. In 2004, a protocol of annual cine MR follow-up was instituted as a result of a case of fatal late failure. The authors evaluated all cases of late failure identified through cine MR imaging and performed a statistical analysis to investigate the relationship between ETV failure and several variables, including the cause of hydrocephalus for which ETV was originally indicated.
In a series of 84 patients (age range 6 days–16 years), 17 patients had early ETV failure. Of the remaining 67 patients, 5 (7%) were found to have no CSF flow through the fenestration and recurrent ventriculomegaly when assessed with cine MR imaging at 1, 2, 3, 4, and 7 years after ETV. The patient in whom ETV failure was identified 1 year postoperatively had Dandy-Walker malformation. The patients in whom ETV failure was identified 2, 3, and 4 years postoperatively all had undergone ETV for treatment of postinfective hydrocephalus. The patient in whom ETV failure was identified 7 years postoperatively had a cystic arachnopathy in the fourth ventricle after cerebellar astrocytoma removal.
Patients who undergo ETV for infective hydrocephalus and Dandy-Walker malformation should receive long-term follow-up, because late closure of the stoma may occur progressively and slowly. Intraoperative observation of thickened arachnoid membranes at the level of the interpeduncular cisterns at the first ETV and a progressive decreasing of CSF flow through the stoma on routine cine MR imaging should be considered unfavorable elements entailing a significant risk of deterioration.