Cerebral oxygenation and hemodynamic measurements during craniosynostosis surgery with near-infrared spectroscopy.

INTRODUCTION: Focal pressure-related changes in brain perfusion and metabolism are discussed in single-suture craniosynostosis and brachycephalic cases (bicoronal synostosis). Raised intracranial pressure levels could be measured in some cases. In order to find possible loco-regional brain tissue changes during plastic surgery, we investigated oxygenation and perfusion parameters using non-invasive near-infrared spectroscopy (NIRS) probes. METHODS: Twenty-two consecutively operated cases (mean age 7 months) with single-suture craniosynostosis were prospectively investigated using a NIRS probe (LEA(©), O2C, white light 500-800 nm, laser NIR). Measurements for oxygen saturation (SO(2)), relative quantity of hemoglobin (rHb), blood flow, and blood flow velocity of the bilateral frontal, temporal, and parietal cortices were taken transosseously (prior to decompression) and epidurally directly after decompression as well as 15 and 30 min after decompression and before closure. RESULTS: Twenty-two patients with scaphocephaly (11), trigonocephaly (6), anterior plagiocephaly (3), and brachycephaly (2) were investigated. SO(2) was improving in all patient subgroups, showing the highest levels in the fronto-temporal region; rHb improved in scaphocephalic, trigonocephalic, and brachycephalic children. Again, the highest values were found not only in the temporal but also in the frontal region and in brachycephalic patients also in the parietal cortex. CONCLUSION: These preliminary results of a new technology for brain tissue oxygenation and blood flow measurements suggest a regional compromise of cortical metabolism and circulation in patients with craniosynostosis.

Fetal MRI of the central nervous system: clinical relevance.

OBJECTIVE: Specific conditions of the mother sometimes reduce the quality of ultrasound. In these cases, fetal magnetic resonance imaging (MRI) can be performed after gestational week (GW) 18. Interpretation of subtle disorders or malformations becomes safe not before GW 23. Clinical development of children with central nervous system (CNS) disorders is not predictable with imaging alone. Statistical evidence and personal experience of the medical team are essential in counseling, but optimized imaging is helpful in being more precise. The value of fetal MRI (fMRI) is evaluated. MATERIALS AND METHODS: Twenty-five pregnant women (30.5 +/- 4.5 years) were investigated by additional fMRI. TECHNIQUE: Breath-hold technique with T2 half-Fourier acquisition single-shot turbo spin-echo and T1 FLASH-2D images in three dimensions with field of view of 350 x 400 mm. All cases have been correlated with postnatal MRI, ultrasound, and clinical follow-up. RESULTS: In all fetuses, diagnostic MRI was performed 3-10 days after ultrasound between GW 22 and 34 (GW 26.1 +/- 3.6). Sedation was not necessary. In eight cases of suspicious ultrasound, fMRI confirmed ultrasound findings. In 13 cases, additional diagnoses or exclusions of suspected findings could be established. Complete revision of diagnosis was realized in four cases. Findings could be confirmed by postnatal MRI in 11 patients. The clinical course was not predictable in cases with ambivalent prognosis. CONCLUSIONS: Prenatal diagnosis of CNS pathologies should result in parental counseling. Sufficient diagnostic information, statistical data, and experience of the involved professionals are essential. These results show that in detecting congenital CNS abnormalities fMRI is superior to ultrasound and should be considered in difficult cases.

Decompressive craniectomy in severe brain injury.

OBJECT: The goal of this study was to evaluate the therapeutic role of decompressive craniectomy in severe brain injury. METHODS AND RESULTS: Between 1996 and 1998 we treated 87 patients with severe brain injury (GCS 3-8) in our department. In 70 cases follow up data could be obtained. Mean age was 49 years (range 1-79). Initial CT scans of all patients demonstrated diffuse brain injury with generalised brain swelling and/or mass lesion. In 51 of these patients uni (n=40)- or bilateral (n=11) decompressive craniectomy was performed initially or secondarily after failure of standard treatment. In a retrospective analysis we performed statistical tests of the follow-up group. The mortality rate did not show a significant difference between the two treatment groups (p=0.802) with a slight advantage for the decompression. The log-rank-test demonstrated a non-significant improvement of the survival time for decompressed patients (p=0.632). Secondary decompression showed a significantly better survival rate and time compared to primary decompression. In all 7 pediatric cases (1-16 yrs) we performed craniectomy. 2 of them died immediately post emergency operation, 5 survived with good outcome (1 LOF). CONCLUSIONS: A slight, but non-significant benefit could be demonstrated after decompressive craniectomy in the whole patient population. In young patients decompression seems to have a more positive influence on outcome and survival.

Multimodal target point assessment for stereotactic biopsy in children with diffuse bithalamic astrocytomas.

INTRODUCTION: Diffuse glial tumors with bithalamic involvement are rare in children. Diagnostic assessment can be difficult as the radiological findings can be unspecific. MATERIALS AND METHODS: In order to enhance the diagnostic yield metabolic imaging with MRS and PET using FET ( O-(2-[(18)F]fluoroethyl)- L-tyrosine) was performed in two children (2 and 10 years of age). Co-registered images were used for image-guided biopsy, which was planned with neuronavigation and stereotaxy simultaneously. RESULTS: Biopsies from the right thalamus were planned, but locations were changed in both cases after metabolic imaging was available. MRS (thalamic voxel) was typical for a glial tumor in one child. In the older girl FET-PET revealed an unexpected lesion in the left cerebellar hemisphere, with a tumor-to-cortex ratio of 3.8, as against 1.7 in the thalamus. Accordingly, a stereotactic biopsy specimen was taken from the left cerebellar hemisphere, and a final diagnosis of anaplastic astrocytoma was made. The other patient showed a higher uptake (tumor-to-cortex ratio 1.6) in the left dorsal thalamus, compared with bilateral homogeneous hyperintensity of the thalamus structures on MRI. Stereotactic biopsy revealed a low-grade diffuse astrocytoma. CONCLUSION: Stereotactic biopsy using metabolic imaging and image fusion can enhance the diagnostic yield in cases of diffuse pediatric gliomas disclosing unexpected 'hot spots'.

[Lumbar nerve root compression--results of the quality assurance study 1993-1998]. / Lumbale Nervenwurzelkompression - Ergebnisse der Qualitätssicherungsstudie von 1993-1998.

Summary. This multicenter quality assurance study investigated 14 334 cases with lumbar nerv root compression between 1993 and 1998. Patient data, diagnostics, therapy and course as well as neurological status pre- and posttreatment have been investigated for each year. There was an obvious growing number of patients between 60 and 79 years of age, who have been operated. The rate raised from 20% to 28%. Age, comorbiditiy and complication rate as well as length of stay showed a positive correlation. Outpatient CTscan lost diagnostic importance (82% --> 65%) compared to MRI (16% --> 41%). Myelography regained interest in only conservatively treated patients due to difficult indication assessment (40% --> 64%). The rate of intraoperative antibiotics rose from 42% to 59% without change of infection rate. Intra- and postoperative complication rates came down from 5.6% to 2.1% and 6.9% to 1.8% respectively. Pre- and postoperative neurological findings remained unchanged.

[Evaluation of the pilot study "Lumbar nerve root compression"]. / Evaluation der Pilotstudie "Lumbale Nervenwurzelkompression"

Summary. In order to evaluate the quality assurance study for patients suffering from lumbar nerve root compression a checklist has been developed according to quality assurance criteria and formal aspects. Together with the study data of the years 1993-1998 and a critical literature review each item of the quality assurance form has been evaluated. It is obvious that outcome oriented quality assurance of this entity is insufficient without assessment of the late outcome.

[Characteristics and outcome perspectives of lumbar nerve root decompression in elderly patients]. / Besonderheiten und Erfolgsaussichten lumbaler Nervenwurzeldekompressionen bei älteren Patienten.

A series of 14 334 cases with lumbar nerve root compression demonstrated between 1993 and 1998 a growing number of operations in elderly patients. In order to assess the treatment results in this patient group the authors evaluated the retrospective multicenter data and performed a prospective clinical study up to 24 months postoperatively in 44 patients of a single institution. The group of patients older than 60 yrs. have been compared to another group being 30-50 yrs. old. Elderly patients showed a complete remission of palsies in 67% and of sensation disorders in 54% compared to 100% and 88% respectively in younger patients. 60% of the elderly and 54% of the younger patients suffered from pain, but less intensively than pre treatment. The postoperative complication rate in older individuals was higher with 25%. In both groups 90% felt that the result of the treatment was "very good" or "good".

Interdisciplinary treatment in pediatric patients with malignant CNS tumors.

Despite sophisticated surgical methods only a few pediatric CNS tumors can be controlled by operation alone. Therefore multimodality treatment regimens are needed to improve quality of life and survival, which is most important in malignant neoplasms. Since 1998 we have treated 16 children with malignant CNS tumors. All 16 patients have been treated on an interdisciplinary basis and are therefore accompanied by a pediatric neurooncology group consisting of a neurosurgeon, pediatric oncologist, and radiotherapist. Depending on tumor histology, child's age, and extent of surgery, further adjuvant therapy is planned by this group. Newly diagnosed tumors are typically treated by a specific chemotherapy protocol according to a multi-institutional study. In recurrent tumors more individual treatment regimens are considered. Data concerning surgery, adjunctive treatment, complications, and outcome of all patients and four case reports are presented.

Cerebellar mutism syndrome.

Since 1980, a growing number of pediatric patients with mutism following posterior fossa surgery have been recognized. This syndrome typically affects children and in rare cases young adults who become mute one or two days after tumor operation but do not show disturbances of consciousness or language comprehension. The disorder persists for 1 to 4 months. The pathogenesis is still unknown. Of 21 children who underwent surgery for large posterior fossa tumors between 1991 and 1995, 6 developed cerebellar mutism. Histologically the tumors were classified as astrocytoma WHO grade I, astrocytoma WHO grade II and ependymoma WHO grade III in one case and medulloblastoma WHO grade IV in three cases. Besides the clinical course, intraoperative findings and CT or MRI data are evaluated and discussed considering possible etiological hypotheses. Our own experience and also literature reviews suggest that the lesion of the cerebellar hemispheres might be the most important one of multiple factors causing cerebellar mutism. Generally the syndrome is transient. The diagnosis should not delay adjuvant therapy in patients with a malignancy.

[Procedure Coding System: background and development]. / Procedure Coding System: Hintergrund und Aufbau.

In the USA, the ICD-10 Procedure Coding System (ICD-10-PCS) was developed because the current system ICD-9-CM Vol. 3 did not allow new technologies to be incorporated as new codes. PCS is a seven-digit muliaxial coding system which covers a broad spectrum of surgical and nonsurgical procedures. Its structure is easily understood and guarantees sufficient expandibility. Background and structure of PCS are presented with examples from surgical sections and discussed in comparison with ICPM.

[Lumbar nerve root compression: a cooperative project for quality assurance in neurosurgery]. / Lumbale Nervenwurzelkompression: Ein kooperatives Projekt zur Qualitätssicherung in der Neurochirurgie.

In 1993 a total of 4152 cases of lumbar nerv root compression have been investigated in 11 neurosurgical departments. Beside patient data diagnostics, treatment and course as well as neurological status before and after treatment were subjects of this quality assurance study. Special emphasis was put on a detailed evaluation of complications. In more than 91% surgical treatment has been performed, in 5% of these cases after an attempt of conservative treatment. Nearly 9% of the patients have not been operated upon. Recurrent disease has been treated surgically in 10.5%. Most common procedure was flavectomy (69%) with discectomy (80%). The all over complication rate was 14%. Typical surgical complications have been rare with 5%. Neurological deterioration after treatment was also rare with less than 2%. The study was able to reflect the present state of treatment in patients with lumbar nerve root compression and the subjects investigated served well as parameters of quality assurance.