Jacopo Lenzi

Long-term follow-up of intramedullary spinal cord tumors : A series of 202 cases

OBJECTIVE:To review a series of patients who underwent surgical removal of intramedullary spinal cord tumors, focusing on the long-term functional outcome, recurrence rates for the various tumors, and technical problems continually debated in neurosurgical practice. METHODS:From December 1972 to June 2003, 202 patients underwent removal of intramedullary tumors. Lesions were located in the cervical spinal cord in 61 patients (30%), at a dorsal site in 60 (29%), at a cervicodorsal site in 51 (25%), and in the medullary cone in 30 (15%). The most frequent histological tumor types were astrocytomas (86 patients, 42%) and ependymomas (68 patients, 34%). RESULTS:Of the 68 ependymomas, 55 (81%) were completely removed and 13 (19%) incompletely removed. In 66% of the patients (42 patients), the presenting signs and symptoms remained unchanged at long-term follow-up; in 25% (16 patients), they improved; and in 9% (6 patients), the clinical status worsened. Of the 27 Grade I astrocytomas, 22 (81%) were completely removed and 5 (19%) incompletely removed. Functional assessment of the 23 patients available at “late” follow-up showed that 26% (6 of 23 patients) had improved, 9% (2 of 23 patients) had worsened, and 66% (15 of 23 patients) remained unchanged from preoperative status. Conversely, of the 41 Grade II astrocytomas, only 5 (12%) were completely removed, and 10% had improved. None of the 18 Grade III to IV astrocytomas could be completely removed. In 61% (11 of 18 patients), the postoperative functional status worsened. CONCLUSION:Determinant predictors of a good outcome after surgery for intramedullary spinal cord tumors are histological type of lesion, complete removal of the lesion, and a satisfactory neurological status before surgery.

Solitary fibrous tumors of the meninges: Report of four cases and literature review

Central nervous system solitary fibrous tumors are a new pathological entity. To our knowledge, only 60 meningeal solitary fibrous tumors both in the spinal cord and in the brain have been described in the literature. The 56 previously reported cases of meningeal solitary fibrous tumors are critically reviewed. In addition, we report four new cases of solitary fibrous tumors of the meninges. There is a slight male prepoderance. Meningeal solitary fibrous tumors show a tendency to arise in the posterior fossa (26%) and spine (25%). The treatment was mainly total surgical excision. Radiotherapy was given only to four patients with tumors involving the cerebral parenchyma. Sporadic cases of recurrence and distant metastasis have been reported. The prognosis of meningeal solitary fibrous tumors is still unknown because the follow-up of the reported cases is short. It is probable that cases of solitary fibrous tumors of the meninges have been misdiagnosed as other tumors in the past. The best management of these tumors seems to be total surgical excision whenever possible. It is important that every new case of meningeal SFT be reported to throw light on this particular tumor and to affirm its status as a clinicopathological entity.

High-grade intramedullary astrocytomas: 30 years' experience at the Neurosurgery Department of the University of Rome "Sapienza".

OBJECT The goal in this study was to review a series of patients who underwent surgical removal of intramedullary high-grade gliomas, focusing on the functional outcome, recurrence rates, and technical problems continually debated in neurosurgical practice. METHODS Between December 1976 and December 2006, 22 patients underwent removal of intramedullary high-grade gliomas. Lesions were located in the cervical spinal cord in 12 patients, and in the thoracic cord in 10. RESULTS Histological examinations showed 10 Grade III astrocytomas and 12 glioblastomas. Only 2 of the 22 high-grade astrocytomas could be completely removed. The clinical postoperative status worsened in 14 patients (63.6%), was unchanged in 7 patients (31.8%), and there was 1 case of intraoperative death (4.5%). None of the 22 patients showed improvement in their neurological status postoperatively. In this series, excluding the 1 intraoperative death, all patients died of progression of the malignancy. CONCLUSIONS Surgical treatment did not ameliorate the postoperative neurological status; instead, in the majority of cases, it prompted a worsening of the deficit. Radiotherapy and chemotherapy have a little influence on the length of survival. In this series, multimodality treatment of intramedullary high-grade astrocytomas has been shown to increase length of survival without improving the neurological status.

Surgical treatment and clinical outcome of GH-secreting adenomas in elderly patients.

Summary. Patients older than 65 years represent 3–5% of all acromegalic patients. The old age of the patients and the higher incidence of cardiovascular and metabolic complications related to acromegaly could increase the intra- and peri-operative risk, so that medical treatment is usually recommended as a therapy of choice. The aim of this retrospective study was to investigate the impact of transsphenoidal surgery in a series of 22 elderly patients with active acromegaly, with special regard to anaesthesiological risk, peri-operative complications, and clinical outcome. Despite an increased anesthesiological risk being present in 16/22 patients, no complication occurred during surgery. Similarly, no post-operative mortality or major complications were observed. Biochemical cure, defined at 6 months by glucose-suppressed plasma GH levels below 1 ng/ml and normal age-corrected IGF-I value levels, was achieved in 68% of patients and no recurrence of disease was observed in the subsequent follow-up (mean 5.2±2.1 years). A significant cardiovascular improvement was observed in cured patients, with a decrease of left ventricular mass index (91.3±20.1 vs 115.9±15.0 g/m2; P<0.005), as measured by echocardiography, as well as a slight but significant decrease of systolic and diastolic blood pressure values (130.0±12.1 mmHg vs 137.6±13.5 mmHg P<0.05; and 84.2±6.4 mmHg vs 88.8±7.5 mmHg P<0.05, respectively). A significant post-operative improvement of glucose tolerance was also observed in this group. We conclude that transsphenoidal surgery, if well planned and carefully performed, is safe and able to induce a significant cardiovascular and metabolic improvement even in elderly acromegalic patients.

Sacral Tarlov Cyst: Surgical Treatment by Clipping

BACKGROUND This study reports the anatomopathological classification of Tarlov cysts and the various treatment techniques described in the literature. METHODS The authors present their patient series (19 cases) with a long follow-up (range 9 months to 25 years) treated by cyst remodeling around the root using titanium clips. RESULTS The technique is effective in both avoiding cerebrospinal fluid leakage and resolving bladder dysfunction when urinary symptoms are incomplete and discontinuous. CONCLUSIONS The clipping technique for Tarlov cysts is easy, valid, safe, rapid, and effective.

Pseudo-aneurysm of a lumbar artery after flexion-distraction injury of the thoraco-lumbar spine and surgical realignment: rupture treated by endovascular embolization.

Study Design. A unique case of pseudo-aneurysm of a lumbar artery after injury of the thoracolumbar spine was presented. Objective. To describe the exceptional occurrence of pseudo-aneurysm of a lumbar artery after flexion-distraction fracture of thoracolumbar junction and to discuss the mechanism of formation and the therapeutic solution. Summary of Background Data. Injury of a lumbar artery represents a potential cause of massive, life-threatening, retroperitoneal bleeding. It may be associated with lesions of the abdomen, lower limbs, pelvic bones, and spinal column. Fracture of a transverse process may be responsible for direct laceration of a lumbar artery, but formation of a pseudo-aneurysm is an uncommon event. The diagnosis is difficult and often delayed. The treatment of choice is endovascular embolization. Methods. In a patient who had a posttraumatic severe thoracolumbar vertebral dislocation with complete spinal cord lesion after road accident, we performed surgical reduction and stabilization via posterior approach. After 7 days, he developed a progressive anemia due to retroperitoneal hemorrhage and formation of a pseudo-aneurysm of the lumbar artery at L1 level. Results. Endovascular embolization achieved resolution of the pseudo-aneurysm, regression of the hematoma and progressive recovery of the patient during a period of 6 months. Conclusion. Pseudo-aneurysm of a lumbar artery has never previously been described in association with flexion-distraction type vertebral fracture, in which the spinal column is subjected to greater, shear-type, forces. Stretching of the arterial wall due to the traumatic dislocation of the spine and subsequent surgical realignment may be considered as the mechanism of formation and rupture of the pseudo-aneurysm. Dangerous bleeding in the retroperitoneal space and in the operative field can be effectively managed by endovascular intervention.

Neurosurgical Applications of the 2-μm Thulium Laser: Histological Evaluation of Meningiomas in Comparison to Bipolar Forceps and an Ultrasonic Aspirator

OBJECTIVE The authors evaluated the histological effects of the 2-μm thulium laser on meningioma tissue, comparing them to the results obtained using bipolar forceps and an ultrasonic aspirator. METHODS The authors analyzed nine samples of intracranial meningiomas. Four slices were obtained for every sample, and one incision was performed on each slice. Two incisions were made with a 2-μm thulium laser (one set to a 6 W and another set to a 12 W power level). One incision was made using a bipolar forceps and the other using an ultrasonic aspirator. Tissue was addressed and analyzed. Upon microscope analysis, three zones of laser action were identified: (A) a central crater; (B) a vaporized zone; and (C) a shrunken layer. These three layers were measured and compared. RESULTS When addressed with the laser, all nine meningiomas presented a crater having an average depth of 1 mm. Three layers were clearly distinguished and measured: A (average depth: 0.8 mm at 6 W and 1.24 mm at 12 W); B (average depth: 0.32 mm at 6 W and 0.72 mm at 12 W); and C (average depth: 0.39 mm at 6 W and 0.44 mm at 12 W). On slices treated with bipolar forceps incisions, only zones B and C were identified. Ultrasonic aspirator incisions showed a deeper A zone (average depth: 2.93 mm), no B zone, and a tiny C zone (average depth: 0.16 mm). CONCLUSIONS Thulium laser can be safely used for the surgical removal of intracranial meningiomas; beyond 2 mm under the surface of action, no tissue alterations were found. The lesions produced on meningiomas were characterized by vaporization and shrinking. When compared with bipolar forceps, the thulium laser offers cutting precision and vaporization of the tissue. When compared to the cavitron ultrasonic surgical aspirator (CUSA), the laser offers shrinking and coagulation of small vessels.

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.

Assessment of the utility of the 2‐µ thulium laser in surgical removal of intracranial meningiomas

Since the 1960s, lasers have been used in neurosurgery for surgical removal of intracranial tumors. Because of its limited penetration (2 mm) through tissues and its wavelength, which is useful in water medium, the 2‐µ thulium laser has been applied primarily in urology. Its features are attractive for application under microscope magnification during neurosurgical procedures. The aim of this study was to evaluate the usefulness of the 2‐µ thulium laser during microsurgical removal of intracranial meningiomas.

Midline medulloblastoma versus astrocytoma: the position of the superior medullary velum as a sign for diagnosis

PurposeWe wish to describe the position of the superior medullary velum (SMV) in midline posterior fossa tumours as a sign in helping to distinguish between midline medulloblastoma and midline astrocytoma.Material and methodsSagittal T1-weighted MRI images of 21 consecutive patients with histologically documented posterior fossa midline astrocytomas (nine cases) and medulloblastomas (12 cases) were reviewed, with respect to the position of the velum medullare superius.ResultsIn all medulloblastomas the SMV was superiorly dislocated; in eight astrocytomas it was anteriorly and/or inferiorly disclocated; only in one astrocytoma the SMV presented upward dislocation.ConclusionIn the differential diagnosis between medulloblastoma and astrocytoma the upward dislocation of the SMV is strongly suggestive of medulloblastoma.