Luigi Maria Cavallo

Application of neuroendoscopy to intraventricular lesions.

We present an overview of the history, development, technological advancements, current application, and future trends of cranial endoscopy. Neuroendoscopy provides a safe and effective management modality for the treatment of a variety of intracranial disorders, either tumoral or non-tumoral, congenital, developmental, and degenerative, and its knowledge, indications, and limits are fundamental for the armamentarium of the modern neurosurgeon.

Endoscopic Endonasal Transsphenoidal Approach to the Sellar Region

This chapter deals with the main aspects of the standard transsphenoidal approach to the sella by means of a “pure” endoscopic technique. With this term we mean a transsphenoidal procedure performed with an endoscope as the sole visualizing instrument during the whole operation. After almost a decade, this can be considered a regular way of surgical management of lesions of the sellar compartment, routinely employed in some centers. Special aspects, such as extended approaches to the skull base by means of variations of the standard procedure, will be treated in detail in next chapters of the book, and must be reserved to experienced surgeons.

Pseudoaneurysm of the intracavernous carotid artery following endoscopic endonasal transsphenoidal surgery, treated by endovascular approach.

Carotid artery injury following transsphenoidal microsurgery for sellar lesions [2, 5] or functional endoscopic sinus surgery (FESS) for paranasal sinus pathology [4] is a well known and fortunately uncommon complication of these procedures. It occurs more frequently during the course of re-operations and is associated with signi®cant morbidity and mortality. Endoscopicendonasaltranssphenoidalsurgeryhasbeen recently employed in the routine management of pituitary adenomas [3] and has been proposed as the treatment of choice for recurrences [1], but no similar complication has been reported to date.

Cabergoline-induced CSF rhinorrhea in patients with macroprolactinoma. Report of three cases

Three cases of cerebrospinal fluid (CSF) leak, in subjects with an invasive macroprolactinoma under treatment with cabergoline (CAB), are reported. The patients underwent surgical treatment by means of an endoscopic endonasal transsphenoidal approach, which allowed removal of the lesion and sealing of the fistula. Many cases of CSF rhinorrhea are described in literature after bromocriptine therapy in invasive prolactinomas, but only one report has been recently published of such condition after CAB treatment. The complication is likely due to the brisk cessation of the so-called “stopper effect”, i.e. the tumor mechanically blocking the CSF leak in spite of its previous erosion of the skull-base, when CAB induces the macroprolactinoma shrinkage. Endoscopic transsphenoidal surgery offers a safe, minimally invasive and efficient management of this complication, which allows to regularly perform the following steps of the therapeutical strategy against the prolactinoma.

Clinical comparison of remifentanil–sevoflurane vs. remifentanil–propofol for endoscopic endonasal transphenoidal surgery

Background: Endoscopic endonasal transphenoidal surgery has been recently proposed as a minimally invasive procedure for the treatment of pituitary adenomas. The main objective of the anaesthesiologist is to induce sufficient haemodynamic control together with rapid recovery at the end of surgery. The aim of this study was to examine recovery profile, surgical operative conditions and haemodynamic differences using remifentanil infusion with either propofol target controlled infusion system or sevoflurane. Method: Forty‐four adult patients were enrolled in a prospective, randomized, single‐blind, two‐group study: Group P received propofol target controlled infusion system and remifentanil; Group S received sevoflurane and remifentanil for maintenance of anaesthesia. Results: No statistically significant differences between the two groups with regards to the haemodynamic changes, operative conditions as assessed by a four‐step bleeding score (0–3), were obtained. Recovery times were considerably shorter after remifentanil–sevoflurane in comparison with remifentanil–propofol target controlled infusion system group (7.4 vs. 12.8 min, P < 0.01). Conclusion: This study demonstrates that sevoflurane–remifentanil gives a faster recovery and equivalent intraoperative status compared with propofol target controlled infusion system with remifentanil for the endoscopic endonasal transphenoidal approach.

Remifentanil-TCI and propofol-TCI for conscious sedation during fibreoptic intubation in the acromegalic patient

Background and objective To evaluate the use of remifentanil–propofol administered as target‐controlled infusion during awake fibreoptic intubation for anticipated difficult tracheal intubation in acromegalic patients. Method In all, 20 consecutive acromegalic patients underwent elective endonasal endoscopic transsphenoidal pituitary surgery. After premedication with midazolam 0.03 mg kg−1, initially a target‐controlled infusion of remifentanil 1.0 ng mL−1 and propofol 1.5 &mgr;g mL−1 was started. The fibreoptic intubation was performed by the same physician experienced with the fibreoptic technique. During the fibreoptic procedure the target concentrations of remifentanil and propofol ranged between 1.0 and 5.0 ng mL−1, and between 1.5 and 3.5 &mgr;g mL−1, respectively. Changes in heart rate and mean arterial pressure were recorded during airway manipulation, during tracheal intubation, and at 1 and 3 min after. On the first postoperative day, patient recall and level of discomfort during fibreoptic intubation were evaluated. Results Endotracheal intubation was efficaciously and quickly secured in all patients. A significant increase in mean arterial pressure and heart rate was recorded only during tracheal intubation (P < 0.05). Oxygenation was sufficient and no bradypnea or apnoea was recorded. All patients later described their anaesthetic experience as satisfactory. During fibreoptic intubation, remifentanil (ng mL−1) and propofol (&mgr;g mL−1) mean effect‐site concentrations were 3.2 ± 0.3 and 2.0 ± 1.0, respectively. Conclusion Remifentanil and propofol target‐controlled infusion provided satisfactory conscious sedation allowing for successful oral fibreoptic intubation in acromegalic patients with no recall.

The role of inferior petrosal sinus sampling in ACTH-dependent Cushing's syndrome: review and joint opinion statement by members of the Italian Society for Endocrinology, Italian Society for Neurosurgery, and Italian Society for Neuroradiology

In the management of adrenocorticotropic hormone (ACTH)-dependent Cushings syndrome, inferior petrosal sinus sampling (IPSS) provides information for the endocrinologist, the neurosurgeon, and the neuroradiologist. To the endocrinologist who performs the etiological diagnosis, results of IPSS confirm or exclude the diagnosis of Cushings disease with 80%-100% sensitivity and over 95% specificity. Baseline central-peripheral gradients have suboptimal accuracy, and stimulation with corticotropin-releasing hormone (CRH), possibly desmopressin, has to be performed. The rationale for the use of IPSS in this context depends on other diagnostic means, taking availability of CRH and reliability of dynamic testing and pituitary imaging into account. As regards the other specialists, the neuroradiologist may collate results of IPSS with findings at imaging, while IPSS may prove useful to the neurosurgeon to chart a surgical course. The present review illustrates the current standpoint of these 3 specialists on the role of IPSS.

Dysembryogenetic spinal tumours in adults without dysraphism

The authors report 15 patients with spinal intradural dysembryogenetic tumours with clinical onset in adult age in the absence of clinical and radiological signs of dysraphism. The series includes seven lipomas, four epidermoid cysts, three dermoid cysts and one teratoma. The tumour site was the thoracic region in three cases, the lumbar cord and conus in six, the cauda equina in four and the filum terminale in two. Among 14 patients operated upon, the surgical removal was complete in eight cases, subtotal in two and partial in four. Recurrence was noticed only in one subtotally resected thoracic epidermoid cyst. Magnetic resonance imaging allows a precise diagnosis of these lesions, mainly of small lipomas and dermoids of the conus and filum, where a tethered conus is responsible for clinical symptoms. Dysembryogenetic spinal tumours that become symptomatic in adult age may require surgical treatment. Reduction of the mass and release of any associated tethered neural elements are the goal of surgery for spinal lipomas, whereas epidermoid and dermoid cysts require a more radical treatment. However, even partial resections to avoid neural damage result in a good clinical outcome and very low risk of recurrence.

Very delayed hyponatremia after surgery and radiotherapy for a pituitary macroadenoma

Severe hyponatremia (118 mmol/l) with natriuresis, consistent with cerebral salt wasting syndrome (CSWS), occurred 38 days after transsphenoidal surgery in a 59-year-old woman affected by a pituitary non-functioning macroadenoma. From the 35th day after surgery, she showed progressive polyuria, hypotension and hyponatremia associated with natriuresis, decreased plasma and increased urinary osmolality. The clinical examination revealed signs of dehydration and gradual decline in the level of consciousness. The anterior pituitary function was normal due to appropriate replacement of thyroid and adrenal axis. The patient was treated with saline administration until normal natremia and water balance were restored and neurological symptoms had completely disappeared. This case focuses on the unusually prolonged time of development of post-surgery hyponatremia, despite delayed symptomatic hyponatremia being reported to commonly occur 7 days after transsphenoidal surgery. Therefore, we would advise not to limit the periodic follow-up of the hydroelectrolytic balance to the first two weeks after surgery, but to prolong it until after discharge from hospital. In fact, an early diagnosis is of great importance to prevent permanent neurological damage or death. Since CSWS and syndrome of inappropriate secretion of ADH, the two disorders alternatively imputed to generate post-surgical hyponatremia, are characterized by different pathogenic mechanisms and require opposing therapeutic approaches, the occurrence of extracellular volume dilution or of increased sodium renal loss should be carefully investigated. The evidences in favor of CSWS, the possible mechanisms behind the syndrome and diagnosis and management of patients with post-transsphenoidal surgery CSWS are discussed.

Sellar/Tuberculum Approach

Background: Extending the transsphenoidal approach has allowed its increasing use for suprasellar pathologies. The addition of the endoscope has further advanced this approach. <