Ustilago species causing leaf-stripe smut revisited.

Leaf-stripe smuts on grasses are a highly polyphyletic group within Ustilaginomycotina, occurring in three genera, Tilletia, Urocystis, and Ustilago. Currently more than 12 Ustilago species inciting stripe smuts are recognised. The majority belong to the Ustilago striiformis-complex, with about 30 different taxa described from 165 different plant species. This study aims to assess whether host distinct-lineages can be observed amongst the Ustilago leaf-stripe smuts using nine different loci on a representative set. Phylogenetic reconstructions supported the monophyly of the Ustilago striiformis-complex that causes leaf-stripe and the polyphyly of other leaf-stripe smuts within Ustilago. Furthermore, smut specimens from the same host genus generally clustered together in well-supported clades that often had available species names for these lineages. In addition to already-named lineages, three new lineages were observed, and described as new species on the basis of host specificity and molecular differences: namely Ustilago jagei sp. nov. on Agrostis stolonifera, U. kummeri sp. nov. on Bromus inermis, and U. neocopinata sp. nov. on Dactylis glomerata.

Clinicoradiological features of rosette-forming glioneuronal tumor (RGNT) of the fourth ventricle: report of four cases and literature review.

BACKGROUND: Rosette-forming glioneuronal tumor (RGNT) of the fourth ventricle is a recently characterized rare tumor entity. Despite benign histological features and a reported favorable postoperative course, there is still limited clinical experience with this tumor. METHODS: Retrospective analysis of the clinical, radiological, and surgical data in four patients with RGNT was performed. Mean age at diagnosis was 35 years, and the median follow-up was 19 (range 2-30) months. The results were compared with the literature. RESULTS: Patient 1 presented on an emergency basis due to intratumoral hemorrhage and tumor enlargement followed by life-threatening obstructive hydrocephalus. Patient 2 suffered from headaches and left-sided hemiparesthesia 6 months prior to surgery. Patient 3 developed headaches with nausea and vomiting, followed by left-sided tinnitus 1 year prior to surgery. In patient 4, RGNT was detected incidentally. No differentiating radiological characteristics were seen except for the presence of minute satellite lesions in two patients. Histopathological findings were distinct and showed their typical biphasic neurocytic and glial architecture. No progression/recurrence was seen in the postoperative course. CONCLUSIONS: The spectrum of presenting symptoms of RGNT is wide, nonspecific, and typically depends on tumor size and extent. This tumor entity should be considered in the differential diagnosis of posterior fossa masses in order to avoid undue surgical aggressiveness.

MRI of fetal acquired brain lesions.

Acquired fetal brain damage is suspected in cases of destruction of previously normally formed tissue, the primary cause of which is hypoxia. Fetal brain damage may occur as a consequence of acute or chronic maternal diseases, with acute diseases causing impairment of oxygen delivery to the fetal brain, and chronic diseases interfering with normal, placental development. Infections, metabolic diseases, feto-fetal transfusion syndrome, toxic agents, mechanical traumatic events, iatrogenic accidents, and space-occupying lesions may also qualify as pathologic conditions that initiate intrauterine brain damage. MR manifestations of acute fetal brain injury (such as hemorrhage or acute ischemic lesions) can easily be recognized, as they are hardly different from postnatal lesions. The availability of diffusion-weighted sequences enhances the sensitivity in recognizing acute ischemic lesions. Recent hemorrhages are usually readily depicted on T2 (*) sequences, where they display hypointense signals. Chronic fetal brain injury may be characterized by nonspecific changes that must be attributable to the presence of an acquired cerebral pathology. The workup in suspected acquired fetal brain injury also includes the assessment of extra-CNS organs that may be affected by an underlying pathology. Finally, the placenta, as the organ that mediates oxygen delivery from the maternal circulation to the fetus, must be examined on MR images.

Myeloid sarcoma with multiple lesions of the central nervous system in a patient without leukemia. Case report.

The authors report the unusual case of a 35-year-old woman suffering from left leg numbness and radiculopathy due to multiple lesions in the central nervous system: one right parietal extracranial-intracranial lesion with invasion of the sensory cortex, and two intraspinal, intradural lesions compressing the spinal cord at T3-5 and S 1-4. Biopsy sampling of the extracranial part of the parietal lesion led to a diagnosis of myeloid sarcoma. Further examination revealed no evidence of leukemic disease or myeloproliferative disorder. An aggressive multimodal approach to treatment in this patient with a combination of chemotherapy, whole-body radiotherapy, and allogeneic bone marrow transplantation was started immediately. The patient experienced full neurological recovery and complete disappearance of all lesions. At the 7-year follow-up examination, there was no evidence of disease. To the authors' knowledge, this is the first report of a myeloid sarcoma with both intracranial and intraspinal manifestations in a patient without leukemia.

Feasibility of long-term intraventricular therapy with mafosfamide (n = 26) and etoposide (n = 11): experience in 26 children with disseminated malignant brain tumors.

Treatment options for leptomeningeal disseminated brain tumors are limited by the lack of effective drugs for intrathecal therapy of non-hematologic malignancies. We report on our experience with an intraventricular therapy consisting of mafosfamide, a preactivated cyclophosphamide derivative, and etoposide. Between May 1994 and 2002, 26 patients aged 2-19 years with various intensely pretreated disseminated brain tumors received intraventricular mafosfamide via an indwelling subcutaneous reservoir. Twenty-three of them received a dose of 20 mg. Mafosfamide was administered once or twice weekly until remission was achieved and every 2-6 weeks thereafter as maintenance therapy for a total of 736 administrations (2-63/patient). Since March 1998, two patients were switched to receive intraventricular etoposide and nine received etoposide alternating with mafosfamide. Etoposide was given at a dose of 0.5 mg x 5 d every 3-6 weeks for a total of 122 courses (1-29/patient). Immediate toxicities such as transient headaches, nausea, and vomiting occurred with mafosfamide but were manageable with premedication. Etoposide did not cause any discomfort. No long-term toxicities attributable to intrathecal therapy as evidenced by magnetic resonance imaging or neurologic evaluation were observed. Since all patients received some sort of concurrent anti-cancer therapy, the efficacy of intrathecal therapy cannot be assessed independently. However, seven of 13 patients evaluable for response by cerebrospinal fluid (CSF) cytology developed CSF dissemination under systemic chemotherapy and cleared their CSF only after administration of intrathecal mafosfamide. In conclusion, intraventricularly administered mafosfamide at a dose of 20 mg and etoposide at a dose of 0.5 mg x 5 d for patients over 2 years of age are feasible and safe and may produce responses.

Microsurgical management of postoperative disc space infection.

We analysed seventeen patients with septic postoperative spondylodiscitis (POD) who were managed by early microsurgical removal of the infected necrotic tissue, application of a closed suction-irrigation system (for a mean of 6.7 days), and early mobilisation. The POD was diagnosed clinically by elevated erythrocyte sedimentation rate (ESR) or C-reactive protein (CRP) values and radiographically by computerised tomography scanning or magnetic resonance imaging. According to the sensitivity studies of the obtained pathogens, systemic antibiotics were given, followed by early mobilisation of all patients in a light cast corset. Immediate pain relief was noted in all patients except one, who required a third operation that was followed by rapid clinical improvement. Bacteriological diagnosis was obtained in 88% of the patients. Excellent or good clinical long-term results were achieved in 82% of the patients, whereas 18% had poor results. Elevated ESR/CRP values returned to normal ranges within 6 to 44 days (mean 15 days) after reoperation. All but one patient tolerated early mobilisation (within 2 to 4 weeks) well without any complication. Early microsurgical removal of the necrotic and infected tissue and application of a closed suction-irrigation system supported by specific antibiotic therapy should be considered an effective means to treat POD, thereby avoiding a prolonged period of unpleasant immobilisation for the patient.

High-dose remifentanil does not impair cerebrovascular carbon dioxide reactivity in healthy male volunteers.

BACKGROUND: Cerebrovascular carbon dioxide reactivity during high-dose remifentanil infusion was investigated in volunteers by measurement of regional cerebral blood flow (rCBF) and mean CBF velocity (CBFv). METHODS: Ten healthy male volunteers with a laryngeal mask for artificial ventilation received remifentanil at an infusion rate of 2 and 4 microg x kg-1 x min-1 under normocapnia, hypocapnia, and hypercapnia. Stable xenon-enhanced computed tomography and transcranial Doppler ultrasonography of the left middle cerebral artery were used to assess rCBF and mean CBFv, respectively. If required, blood pressure was maintained within baseline values with intravenous phenylephrine to avoid confounding effects of altered hemodynamics. RESULTS: Hemodynamic parameters were maintained constant over time. Remifentanil infusion at 2 and 4 microg x kg-1 x min-1 significantly decreased rCBF and mean CBFv. Both rCBF and mean CBFv increased as the arterial carbon dioxide tension increased from hypocapnia to hypercapnia, indicating that cerebrovascular reactivity remained intact. The average slopes of rCBF reactivity were 0.56 +/- 0.27 and 0.49 +/- 0.28 ml. 100 g-1 x min-1 x mmHg-1 for 2 and 4 microg x kg-1 x min-1 remifentanil, respectively (relative change in percent/mmHg: 1.9 +/- 0.8 and 1.6 +/- 0.5, respectively). The average slopes for mean CBFv reactivity were 1.61 +/- 0.95 and 1.54 +/- 0.83 cm x s-1 x mmHg-1 for 2 and 4 microg x kg-1 x min-1 remifentanil, respectively (relative change in percent/mmHg: 1.86 +/- 0.59 and 1.79 +/- 0.59, respectively). Preanesthesia and postanesthesia values of rCBF and mean CBFv did not differ. CONCLUSION: High-dose remifentanil decreases rCBF and mean CBFv without impairing cerebrovascular carbon dioxide reactivity. This, together with its known short duration of action, makes remifentanil a useful agent in the intensive care unit when sedation that can be titrated rapidly is required.

Rosette-forming glioneuronal tumor of the fourth ventricle.

Rosette-forming glioneuronal tumor (RGNT) of the fourth ventricle has been reported recently as a novel type of primary CNS neoplasm. We present the case of a 35-year-old male patient with RGNT of the fourth ventricle. The tumor was found incidentally; the patient did not suffer from any neurological symptoms. The tumor mass involved the caudal cerebellar vermis, filled the fourth ventricle and protruded into the caudal part of the mesencephalic aquaeduct. Smaller tumor nodules were visible in the adjacent right cerebellar hemisphere. Histologically, prominent neurocytic rosettes with synaptophysin expression were embedded in a glial tumor component resembling pilocytic astrocytoma. Clinicopathological features of our case closely resemble those reported in the original description. Thus, our case confirms RGNT as a new distinct type of primary CNS neoplasm. Due to its distinct features, adoption of RGNT as a new entity into the WHO classification of tumors should be considered.

Prone position in subarachnoid hemorrhage patients with acute respiratory distress syndrome: effects on cerebral tissue oxygenation and intracranial pressure.

OBJECTIVE: To analyze the effect of prone position on cerebral perfusion pressure and brain tissue oxygen partial pressure in subarachnoid hemorrhage patients with acute respiratory distress syndrome (ARDS). DESIGN: Clinical study with retrospective data analysis. SETTING: Neurosurgical intensive care unit of a primary level university hospital. PATIENTS: Sixteen patients treated for intracranial aneurysm rupture with initial Hunt and Hess grade III or worse who developed ARDS within 2 wks after the bleeding. INTERVENTIONS: Routine neurosurgical intensive care treatment for subarachnoid hemorrhage and posthemorrhagic vasospasm including cerebral monitoring with continuous intracranial pressure and brain tissue oxygen partial pressure recordings. MEASUREMENTS AND MAIN RESULTS: Hemodynamics, arterial oxygenation, ventilatory setting, intracranial pressure, cerebral perfusion pressure, and brain tissue oxygen partial pressure in the supine as well as in the prone position were analyzed and compared. A significant increase in Pao(2) from 97.3 +/- 20.7 torr (mean +/- sd) in the supine position to 126.6 +/- 31.7 torr in the prone position was joined by a significant increase in brain tissue oxygen partial pressure from 26.8 +/- 10.9 torr to 31.6 +/- 12.2 torr (both p <.0001), whereas intracranial pressure increased from 9.3 +/- 5.2 mm Hg to 14.8 +/- 6.7 mm Hg and cerebral perfusion pressure decreased from 73.0 +/- 10.5 mm Hg to 67.7 +/- 10.7 mm Hg (both p <.0001). CONCLUSIONS: The beneficial effect of prone positioning on cerebral tissue oxygenation by increasing arterial oxygenation appears to outweigh the expected adverse effect of prone positioning on cerebral tissue oxygenation by decreasing cerebral perfusion pressure in ARDS patients.

High diagnostic accuracy of cytologic smears of central nervous system tumors. A 15-year experience based on 4,172 patients.

OBJECTIVE: To investigate the diagnostic accuracy and current role of intraoperative cytologic smears of central nervous system tumors. STUDY DESIGN: Retrospective analysis of 4,172 patients operated on during 1985-1999, with 3,541 intraoperative smears performed during open procedures and 631 during stereotactic biopsies. RESULTS: Complete correlation with the final diagnosis was achieved in a mean of 89.8% (range, 83-93.7% per year). Diagnostic accuracy increased to 95% on average (range, 91.5-96.7% per year) when cases of partial correlation, mainly due to grading deviations, were included. The most accurate intraoperative diagnoses were obtained in cases of meningioma (97.9%), metastasis (96.3%) and glioblastoma (95.7%). A significant reduction in diagnostic accuracy was observed in cases of oligodendroglioma (80.9%) and ependymoma (77.7%). Besides diagnosis and grading, smear cytology provided resection guidance in cases of well-delineated tumors. CONCLUSION: Intraoperative smears in neurosurgery are easy to obtain and inexpensive and have high diagnostic accuracy. In addition to stereotactic biopsy procedures, intraoperative smears permit reliable intraoperative guidance during lesion targeting and resection.

Are there time and cost savings by using telemanagement for patients on intensified insulin therapy? A randomised, controlled trial.

BACKGROUND: Patients with insulin dependent diabetes require frequent advice if their metabolic control is not optimal. This study focuses on the fiscal and administrative aspects of telemanagement, which was used to establish a supervised autonomy of patients on intensified insulin therapy. METHODS: A prospective, randomised trial with 43 patients on intensified insulin therapy was conducted. Travelling distance to the diabetes centre was 50 min one way; all patients had undergone a diabetes education course with lessons in dose adaptation. Patients were randomly assigned to telecare (n=27) or conventional care (n=16). They used BG-meters with a storage capacity of 120 values (Precision QID Abbott/Medisense) and transmitted their data over a combined modem/interface via telephone line to the diabetes centre. Data were displayed and stored by a customised software (Precision Link Plus, Abbott/Medisense). Advice for proper dose adjustment was given by telephone. RESULTS: Average time needed for instruction in the telemedical system was 15 min. Data were transmitted every 1-3 weeks and a teleconsultation was performed by phone every 2-4 weeks, depending on the extent of specific problems. On average, personal visits in the control group were performed once a month. Physician's time expenditure for telemanagement, compared to conventional advice was moderately higher (50 vs. 42 min per month). A substantial amount of time on the patients side could be saved through replacing personal communications by telephone contacts and data transmission reduction (96 vs. 163 min/month including data transmission time). Setting up an optimal telemanagement scenario, a cost analysis was carried out yielding savings of approximately 650 euro per year per patient. HbA(1c) dropped significantly from 8.2 to 7.0% after 8 months of observation, but there was no significant difference between the intervention and control groups. Major technical problems with the telematic system did not occur during the study. CONCLUSIONS: Telemanagement of insulin-requiring diabetic patients is a cost and time saving procedure for the patients and results in metabolic control comparable to conventional outpatient management.

Individual variations in the sulcal anatomy of the basal temporal lobe and its relevance for epilepsy surgery: an anatomical study performed using magnetic resonance imaging.

OBJECT: The concept of selective amygdalohippocampectomy is based on pathophysiological insights into the epileptogenicity of the hippocampal region and the definition of the clinical syndrome of mesial temporal lobe epilepsy (TLE). High-resolution magnetic resonance (MR) imaging allows correlation of the site of histologically conspicuous tissue with anatomical structure. The highly variable sulcal pattern of the basal temporal lobe, however, definitely complicates the morphometric analysis of histomorphologically defined subdivisions of the hippocampal region. The goal of this study was to define individual variations in the sulcal anatomy on the basis of preoperative MR images obtained in patients suffering from TLE. METHODS: The authors analyzed coronal MR images obtained in 50 patients for the presence of and intrinsic relationships among the rhinal, collateral, and occipitotemporal sulci. The surface relief of consecutive sections of 100 temporal lobes was graphically outlined and the resulting maps were used for visual analysis. The sulci were characterized by measurement of their depth, distance to the temporal horn, and laterality. The anatomical measurements and frequencies of sulcal patterns were assessed for statistical correlation with patients' histories and the lateralization of the seizure focus. CONCLUSIONS: Statistical assessment shows that patient sex is a significant factor in sulcal patterns. Anatomical measurements are significantly decreased on the side of the seizure origin, which relates to loss of white matter, a known morphological abnormality associated with TLE. Magnetic resonance imaging allows for accurate preoperative knowledge of individual sulcal patterns and facilitates intraoperative orientation to anatomical landmarks.