Giancarlo D’Andrea

Pre-surgical planning and MR-tractography utility in brain tumour resection.

The purposes of this study were (1) to evaluate the possible identification of trajectories of fibre tracts, (2) to examine the useful of a neuronavigation system for pre-surgical planning, (3) to assess pre- and post-surgery patients’ clinical condition and (4) to evaluate the impact of this information on surgical planning and procedure. Twenty-eight right-handed patients were prospectively and consecutively studied. All the patients were clinically assessed by a neurologist in both pre- and post-surgical phases. Separately the pyramidal tract, optic radiation and arcuate fasciculus were reconstructed. The trajectories were considered suitable for surgical planning if there were no interruptions of any of the layers at the level of the lesion. Dedicated software ‘merged’ the acquired images with the tractographic processing, and the whole dataset was sent to the neuronavigation system. The assessment of the 37 visualised trajectories close to the tumour resulted in a modification of the surgical approach to corticotomy in six patients (21%); the impact on the definition of the resection margins during surgery was 64% (18 cases). The overall impact percentage on the surgical procedure was 82%. In 27 cases, the symptoms had not changed. MR-tractography provides the neurosurgeon with a new anatomical view that has an impact on the surgical resection planning for brain neoplasms.

Intradural lumbar disc herniations: the role of MRI in preoperative diagnosis and review of the literature

The goal of this article is to report our experience on intradural lumbar disc herniation, consider the causes of this pathology, and analyze it from clinical, diagnostic, and therapeutic perspectives with a particular emphasis on the role of MRI in preoperative diagnosis. We analyzed nine patients treated surgically for intradural lumbar disc hernia. All of them underwent surgery, and hemilaminectomy was performed. In six cases, the diagnosis of intradural herniation was definitive and, in the three remaining, it was confirmed at surgery. In five cases, CT (with no contrast medium) of the lumbar area revealed disc herniation, but none could it confirm its intradural location. Myelography was performed in two cases but also could not prove intradural extrusion. Magnetic resonance imaging study was used in four cases. In five, the postoperative outcome has been excellent. Patients 6 and 9 recovered anal function postoperatively; patient 6 suffered from occasional and mild micturition urgency. The three patients previously operated (1, 2, 7) showed good outcome. Presently, we believe that radiologic diagnosis of intradural herniation is possible in carefully selected patients, thanks to MRI with gadolinium.

Role of magnetic resonance tractography in the preoperative planning and intraoperative assessment of patients with intra-axial brain tumours

PurposeThis study was conducted to assess the possibility of identifying precise white matter tracts situated in proximity to intracranial tumours, to define the anatomical and topographical relations between the same white matter tracts and the tumour, to verify the possibility of integrating tractographic images in the context of a package of three-dimensional anatomical images to send to the neuronavigation system, to assess the impact of this information on surgical planning, and to analyse, both pre-and postoperatively, the patient’s clinical conditions as an index of the functional integrity of the fibres themselves.Materials and methodsTwenty-five patients underwent diffusion tensor study prior to neurosurgery. With the use of dedicated software, relative colour maps were obtained and the trajectories of the white matter tracts adjacent to the tumour were reconstructed in three dimensions. These were then processed for preoperative planning. Planning, which was performed with the neuronavigator, was based on analysis of the location of the course of the main white matter tracts adjacent to the lesion (pyramidal tract, optic radiation and arcuate fasciculus). Two neurosurgeons were asked whether the tractography images had modified the access and/or intraoperative approach to the tumour. All patients were clinically assessed both pre-and postoperatively 1 month after the procedure to define the presence of symptoms related to the involvement of the white matter tracts studied and therefore to assess the integrity of the fibres after the operation.ResultsIn one patient, the tumour was situated away from all the tracts studied and did not compress them in any way. Overall, 40/75 tracts studied had no anatomical relation with the tumour, were not displaced by the tumour or could not be visualised in their entire course. Analysis of the remaining 35 white matter tracts led to an a priori change in the surgical approach for corticotomy in four patients (16%), with no disagreement between the two neurosurgeons and an impact on the extent of resection during surgery in 17 (68%), thus an overall impact on the surgical procedure in 80% of cases. Eight patients showed no symptoms related to the involvement of the white matter tracts studied. In the remaining 17 patients, the symptoms were related to involvement of the pyramidal tract, arcuate fasciculus or optic radiation. At 1-month follow-up, one previously asymptomatic patient reported a speech disorder (transcortical sensory dysphasia); in the remaining 24, symptoms remained unchanged, with a tendency to improvement in 14/17 with symptoms related to involvement of white matter tracts studied.ConclusionsMagnetic resonance (MR) tractography offers the neurosurgeon an anatomical panoramic view that can improve surgical planning for the resection of intracranial tumours. Despite the high incidence of cases in which the lesion is responsible for changes that hinder the reconstruction of white matter tracts, the technique can change the surgical approach for corticotomy, defines the extent of resection and leads to some change in the procedure in 80% of cases. The improvement of pre-existing symptoms and the absence of new symptoms in the postoperative phase, in our opinion, confirms the value of the technique.RiassuntoObiettivoValutare la possibilità di identificare definiti fasci di sostanza bianca localizzati in prossimità di un tumore cerebrale; definire le relazioni anatomiche e topografiche tra gli stessi fasci di sostanza bianca e il tumore; verificare la possibilità di integrare le immagini trattografiche nell’ambito di un pacchetto di immagini anatomiche tridimensionali da inviare a un sistema di neuronavigazione; valutare l’impatto di queste informazioni sulla programmazione chirurgica e analizzare, prima e dopo l’intervento chirurgico, le condizioni cliniche dei pazienti, come indici di integrità funzionale delle fibre stesse.Materiali e metodiVenticinque pazienti, che avevano preventivamente eseguito uno studio del tensore di diffusione, sono stati successivamente sottoposti a intervento neurochirurgico. Mediante un software dedicato, sono state ottenute le relative mappe colorimetriche e ricostruite in tre dimensioni le traiettorie dei fasci di sostanza bianca adiacenti alla neoformazione che sono state elaborate per la pianificazione preoperatoria. La pianificazione, effettuata mediante il neuronavigatore, si è basata sull’analisi della localizzazione e del decorso dei principali fasci di sostanza bianca adiacenti la lesione (fascio cortico-spinale, radiazione ottica e fascicolo arcuato). È stato chiesto a due neurochirurghi se e come la disponibilità della trattografia avesse modificato l’accesso e/o l’approccio intraoperatorio alla neoplasia. Tutti i pazienti sono stati valutati clinicamente sia in fase pre-che post-operatoria, a 1 mese dall’intervento, per definire la presenza di sintomi riferibili a un coinvolgimento dei fasci mielinici oggetto dello studio e verificare quindi, dal punto di vista clinico, l’integrità degli stessi in seguito all’intervento.RisultatiIn un paziente il tumore era localizzato a distanza da tutti i fasci considerati e non determinava sugli stessi effetti compressivi. Globalmente, dei 75 fasci considerati, 40 non avevano rapporto anatomico con il tumore, non venivano dislocati dallo stesso o non risultavano visualizzabili in tutto il loro decorso. L’analisi dei restanti 35 fasci di sostanza bianca considerati ha determinato una modifica a priori dell’approccio chirurgico di corticotomia in 4 pazienti (16%) senza casi di discrepanza nel giudizio tra i due neurochirurghi e un impatto sulla definizione dei limiti di resezione durante l’intervento in 17 (68%), risultando complessivamente di impatto sulla procedura chirurgica nell’80% dei casi. Otto pazienti non mostravano sintomi riferibili a un coinvolgimento dei fasci mielinici oggetto dello studio. Nei restanti 17 i sintomi erano riferibili a un coinvolgimento del fascio piramidale, arcuato o della radiazione ottica. Al controllo a 1 mese un paziente, precedentemente asintomatico, riferiva un disturbo del linguaggio a tipo disfasia sensoriale; nei restanti 24 la sintomatologia era invariata con tendenza al miglioramento in 14 dei 17 pazienti sintomatici per coinvolgimento dei fasci mielinici segnalati.ConclusioniLa tecnica della trattografia con RM offre al neurochirurgo una nuova panoramica anatomica che permette una migliore pianificazione della procedura chirurgica di resezione di patologia cerebrale. Nonostante l’elevata incidenza di casi in cui la patologia determina modificazioni che inficiano la possibilità di ricostruire i fasci di sostanza bianca, la tecnica modifica l’approccio chirurgico di corticotomia, consente di definire i limiti di resezione e determina globalmente un cambiamento dell’intervento nell’80% dei casi. Il miglioramento della sintomatologia pre-esistente e l’assenza di nuovi sintomi in fase post-operatoria conferma, a nostro avviso, la sua validità.

Solitary cerebral metastases from ovarian epithelial carcinoma: 11 cases

Ovarian cancer is quite common in women, but brain metastases from ovarian cancer are considered rare. Eleven patients with solitary cerebral metastasis from ovarian epithelial carcinoma were treated at the Neurosurgical Department of University of Rome La Sapienza, between 1980 and 2000. We treated all of the 11 patients by surgical en bloc removal and by postoperative radiotherapy and chemotherapy. Mean survival was 28 months, and the cause of death was recurrence of the systemic disease in all cases. Multimodal treatment by surgery, radiation and chemotherapy is the best choice of treatment and leads to a median survival of about 20 months.

Idiopathic intracranial hypertrophic pachymeningitis: two case reports and review of the literature.

In 1949, Naffziger et al. first described idiopathic intracranial hypertrophic pachymeningitis (IIHP) as an aseptic, diffuse inflammatory disease that causes thickening of the dura mater and often headache and progressive multiple nerve palsies due to fibrous entrapment or ischemic damage of neurovascular structures. Pachymeningeal thickening can be diffuse or nodular. We report two cases of IIHP; one was affected by diffuse IIHP, while the other presented focal IIHP mimicking a convexity meningioma. We examine the differential diagnosis between IIHP and other known causes of hypertrophic pachymeningitis. We also discuss the clinical bases of treatment.

How to set up a microsurgical laboratory on small animal models: Organization, techniques, and impact on residency training

Microsurgical training is mandatory for the optimal education of modern neurosurgeons. Even though this is a widely acknowledged statement and a lot of institutions around the world practice training in laboratory, the recent literature lacks tip and tricks on how to start a laboratory from scratch, what would be a convenient anesthesia, and what kind of exercises are appropriate. We present our experience in 16 microsurgical training courses settled up at our institutions. Two hundred eleven rodents were dissected. We will describe the organization of the laboratory and of the training courses and we will discuss its practical impact on the residency program.

Management of the entered frontal sinus

The opening of the frontal sinus is a common occurrence in surgical practice. It may involve many surgical disciplines. The complications that may derive from incorrect treatment of an opened frontal sinus are potentially fatal. Unfortunately, the treatment of patients with injured frontal sinus is not uniform and standardized. Here, we describe our technique of treatment. We propose our treatment modality on the basis of our personal experience, which has been excellent in the past 20 years, that is from the time of the technique’s introduction and routine application.

Retroperitoneal mesenchymal chondrosarcoma mimicking a large retroperitoneal sacral schwannoma

We report a case of retroperitoneal chondrosarcoma in which preoperative radiological study induced to a possible diagnosis of sacral schwannoma. A 25-year-old woman was admitted to our neurosurgical institute for a progressive sciatic pain with gait difficulties with a sudden radicular deficit with right positive Lasegue’s sign at 30°, loss of Achilles reflex, sensory deficit on right S1 dermatome, and complete motor deficit of right plantar flexion. We performed an en bloc removal of the lesion via an anterior retroperitoneal approach. We believe that the treatment of choice is radical surgical excision of the tumor with complete en-bloc removal of the lesion; postoperative radiotherapy and chemotherapy should be valuated case by case.

One-Step Posterior and Anterior Combined Approach for L5 Retroperitoneal Schwannoma Eroding a Lumbar Vertebra

We report the case of a large lumbar schwannoma eroding the vertebra and originating from spinal canal with invasion of the retroperitoneal space. We also review all the cases in literature reporting lumbar schwannomas eroding the vertebral bodies and invading the retroperitoneal space focusing on the surgical strategies to manage them. Spinal CT-scan revealed a 44 mm × 55 mm inhomogeneous soft-tissue mass arising from the right L5-S1 neural foramen and its most anterior portion had a clear colliquative aspect. Magnetic resonance image showed a neoplastic lesion with homogeneous low signal in T1WI, heterogeneous signal in T2WI, and strong enhancement in postgadolinium examination. It developed as well in the retroperitoneal space, posteriorly to the iliac vein, up to the psoas muscle with wide erosion of the omolateral conjugate foramen. We performed a one-step combined approach together with the vascular surgeon because the lesion was too huge to allow a complete resection via a posterior approach and furthermore its tight relationship with the psoas muscle and the iliac vessels in the retroperitoneal space should be more safely managed via a retroperitoneal approach. We strongly suggest a 1-step surgery first approaching the dumbbell and the intraspinal schwannomas posteriorly achieving the decompression of the spinal canal and the cleavage of the tumor cutting the root of origin and the vascular supply and valuating the stability of the spine for potential artrodesis procedure. The patient must be then operated on via a retroperitoneal approach achieving the complete en bloc resection of the tumor.

The Real Impact of an Intraoperative Magnetic Resonance Imaging–Equipped Operative Theatre in Neurovascular Surgery: The Sapienza University Experience

The fundamental role of technological instruments in contemporary Neurosurgery is undisputed, and intraoperative magnetic resonance imaging (MRI) represents one of the best examples. The use of a modern high-field magnet and the possibility to match the MRI with an operative microscope and an integrated neuronavigation system has led to successful results in the surgical treatment of different diseases. At our institute, we have performed surgery routinely with the aid of intraoperative MRI over the last 15 years. The aim of this article is to report our experience in the management of neurovascular lesions with the use of this device. We experienced that intraoperative MRI enhanced the surgical experience, leading to an improved postoperative outcome in the treatment of different lesions, such as arteriovenous malformations, dural arteriovenous fistulas, intracranial cavernous angiomas, and intracranial aneurysms. There are several advantages provided by the use of intraoperative MRI. The use of intraoperative MRI coupled with the planning station and the neuronavigation system allows one to obtain preoperative 3-dimensional reconstructions of the vessels, which aids the definition of the anatomy of each neurovascular lesion. Furthermore, the possibility performing an intraoperative scan allows a comparison with preoperative images and, subsequently, the updating of the surgical strategy. Intraoperative diffusion-weighted imaging can detect possible territorial ischemia that would be amenable to intensive treatment. Although increased costs, increased surgical times, increased anesthesiology times, and the possible increased risk of surgical infection may represent some major limitation, the use of intraoperative MRI-equipped operative theaters with integrated neuronavigation systems can prove extremely helpful in the management of neurovascular conditions.