Isolated fourth ventricle is not uncommon in complex posthemorrhagic or postinfectious hydrocephalus. When the condition is symptomatic, the current surgical treatment is endoscopic aqueductoplasty, followed by endoscope-assisted placement of a catheter in the fourth ventricle. The authors suggest a very simple method of steering the tip of standard ventricular catheters by using materials commonly available in all operating rooms. The main advantage of this method is that it permits less invasive transaqueductal drainage of trapped fourth ventricles, especially in cases of narrow third ventricle, because the scope and catheter are introduced in sequence and not in a double-barreled fashion. Two illustrative cases are reported.
Pierluigi Longatti, Elisabetta Marton and Salima Magrini
Case report and review of the literature
Elisabetta Marton, Alberto Feletti, Enrico Orvieto and Pierluigi Longatti
✓The authors present the case of a dumbbell-shaped malignant psammomatous melanotic schwannoma of the upper cervical spine involving the C-2 sensory root. The family of the patient had a history of other malignant stromal tumors, without the Carney complex genetic pattern. The 30-year-old female patient complained of experiencing cervical pain and cervical muscle contractions for 6 months, and was admitted to the hospital. The cervical T1-weighted magnetic resonance (MR) images revealed the presence of a slightly hyperintense C2–3 intra–extradural lesion, moderately enhancing, which had eroded and enlarged the intervertebral foramen. The patient workup also included computed tomography scans and angiography. A posterior approach was used to perform a C2–3 hemilaminectomy, including opening of the dura mater and gross-total removal of the lesion. Histopathological examination of the lesion revealed it to be a malignant psammomatous melanotic schwannoma. The cerebrospinal MR image of the patient obtained at the 12-month follow-up examination demonstrated the presence of tumor progression into the subarachnoid space at the C-3 level. The strong malignancy potential of the lesion must be considered in the future management of the patient, especially due to the presence in the family of other stromal tumors such as gastrointestinalstromal tumors and malignant melanomas. The authors review all the literature concerning melanotic schwannomas and report 105 cases of melanotic schwannoma that were not related to the Carney complex. The particular focus of their review is on the characteristics of the malignant progression of melanotic schwannoma, such as local recurrences, metastasis, and survival rate.
Luca Basaldella, Elisabetta Marton, Alessandro Fiorindi, Bruno Scarpa, Hadi Badreddine and Pierluigi Longatti
Massive intraventricular hemorrhages (IVHs) require aggressive and rapid management to decrease intracranial hypertension, because the amount of intraventricular blood is a strong negative prognostic predictor on outcome. Neuroendoscopy may offer some advantages over more traditional surgical approaches on outcome and may decrease the number of shunt procedures that need to be performed.
The authors retrospectively reviewed the clinical and radiological data in 96 patients treated for massive IVH who were admitted between January 1996 and June 2008 to the neurosurgery unit after undergoing emergency CT scanning. Forty-eight patients (Group A) were treated with endoscopic aspiration surgery using a flexible endoscope with a “freehand” technique. A historical group of 48 patients (Group B) treated using external ventricular drain (EVD) placement alone was used as a comparison. The authors compared the radiological results with the clinical outcomes at 1 year according to the modified Rankin Scale and the need for internal CSF shunt treatment in the 2 groups.
Endoscopic aspiration did not significantly affect the outcome at 1 year as determined using the modified Rankin Scale. Patients who underwent endoscopy had an EVD in place for 0.18 days fewer than patients treated with an EVD alone. Patients undergoing external ventricular drainage alone had a 5 times greater chance of requiring a shunting procedure than those treated using neuroendoscopy and external ventricular drainage. Neuroendoscopy plus external drainage reduces shunting rates by 34% when compared with external drainage alone.
The reduction in internal shunt surgery encourages the adoption of neuroendoscopic aspiration of severe IVH as a therapeutic tool to decrease shunt dependency.
Alberto Feletti, Elisabetta Marton, Grazia Marina Mazzucco, Shanna Fang and Pierluigi Longatti
Since children may not be able to complain of progressive reduction in optic acuity, visual assessment in infancy may present practical difficulties. The authors report a case of craniopharyngioma, which led a young child to early blindness before the correct diagnosis could be made. Similar to other reported cases, the authors found that surgery did not substantially modify the preoperative visual deficit. They conclude that minimal improvement in visual acuity can be expected despite successful microsurgical removal of the tumor.
Alberto Feletti, Alessandro Fiorindi, Vincenzo Lavecchia, Rafael Boscolo-Berto, Elisabetta Marton, Veronica Macchi, Raffaele De Caro, Pierluigi Longatti, Andrea Porzionato and Giacomo Pavesi
Despite the technological advancements of neurosurgery, the posterior part of the third ventricle has always been the “dark side” of the ventricle. However, flexible endoscopy offers the opportunity for a direct, in vivo inspection and detailed description of the posterior third ventricle in physiological and pathological conditions. The purposes of this study were to describe the posterior wall of the third ventricle, detailing its normal anatomy and surgical landmarks, and to assess the effect of chronic hydrocephalus on the anatomy of this hidden region.
The authors reviewed the video recordings of 59 in vivo endoscopic explorations of the posterior third ventricle to describe every identifiable anatomical landmark. Patients were divided into 2 groups based on the absence or presence of a chronic dilation of the third ventricle. The first group provided the basis for the description of normal anatomy.
The following anatomical structures were identified in all cases: adytum of the cerebral aqueduct, posterior commissure, pineal recess, habenular commissure, and suprapineal recess. Comparing the 2 groups of patients, the authors were able to detect significant variations in the shape of the adytum of the cerebral aqueduct and in the thickness of the habenular and posterior commissures. Exploration with sodium fluorescein excluded the presence of any fluorescent area in the posterior third ventricle, other than the subependymal vascular network.
The use of a flexible scope allows the complete inspection of the posterior third ventricle. The anatomical variations caused by chronic hydrocephalus might be clinically relevant, in light of the commissure functions.