Biomedical subjects

H Hirschberg

Publications and source records attributed to H Hirschberg.

At least 19 recordsLinked to original sources

PubMed1997

Incorporation of ultrasonic imaging in an optically coupled frameless stereotactic system.

Frameless stereotactic interactive tracking systems relate a point in the surgical field to a corresponding point on the patients MR or CT scans in multiple planes. A basic weakness with these systems is that they cannot compensate for movement of target points due to brain shift caused by CSF drainage or lesion removal. Real time images can be obtained using ultrasonic techniques but the poor quality and definition and the ill-defined scan plane make interpretation difficult and reduce the usefulness of this modality. The authors have combined these two modalities by mounting light emitting diodes (LEDs) on the ultrasonic probe, thus allowing a "virtual tip" to be developed in the centre of the ultrasonic beam, and tracked via an optically coupled frameless stereotactic system (Radionics, OTS). This has allowed a direct correlation between pre-operative MR and the per-operative ultrasonic images using reformatted MR images. Ultrasound images are obtained through a separate skull opening and the image plane is determined by the position of the virtual tip. The ultrasonic and MR images are presented side by side for visual comparison. Minimally invasive tumour resection or haematoma removal could be carried out under ultrasonic guidance with direct interactive relation to the preoperative MR scans. Alternatively interactive image directed surgical procedures can be up-dated in real time by dynamic ultrasonic images taken in clearly defined scan planes.

Brain Mapping↗

PubMed1997

Survival, prognostic factors, and therapeutic efficacy in low-grade glioma: a retrospective study in 379 patients.

PURPOSE: We report survival, prognostic factors, and treatment efficacy in low-grade glioma. PATIENTS AND METHODS: A total of 379 patients with histologic intracranial low-grade glioma received post-operative radiotherapy (n = 361) and intraarterial carmustine (BCNU) chemotherapy (n = 153). Overall survival and prognostic factors were evaluated with the SPSS statistical program (SPSS Inc, Chicago, IL). RESULTS: Median survival (all patients) was 100 months (95% confidence interval [CI], B7 to 113); in age group 0 to 19 years (n = 41), 226 months; in age group 20 to 49 years (n = 263), 106 months; in age group 50 to 59 years (n = 49), 76 months; and for older patients (n = 26), 39 months. Projected survival at 10 and 15 years was 42% and 29%, respectively. Patient age, World Health Organization (WHO) performance status, tumor computed tomography (CT) contrast enhancement, mental changes, or initial corticosteroid dependency were significant independent prognostic factors (p < .05), while histologic subgroup, focal deficits, presence of seizures, prediagnostic symptom duration, tumor category, and tumor stage were not. Patients aged 20 to 49 years with no independent negative prognostic factors (n = 132) had a median survival time of 139 months versus 41 months in patients with two or more factors (n = 33). Patients who presented with symptoms of expansion (n = 97) survived longer when resected (P < .03); otherwise no survival benefit was associated with initial tumor resection compared with biopsy. Intraarterial chemotherapy and radiation doses more than 55 Gy were not associated with prolonged survival. Among 66 reoperated patients, 45% progressed to high-grade histology within 25 months. CONCLUSION: Prognosis in low-grade glioma following postoperative radiotherapy seems largely determined by the inherent biology of the glioma and patient age at diagnosis.

Adolescent↗

PubMed1996

[Prognosis in primary tumors of the central nervous system. A patient material from the Norwegian Radium Hospital 1960-94].

We present the results of a retrospective survey of 1,218 patients treated at the Norwegian Radium Hospital during the years 1980-94 for primary tumours of the central nervous system. Median survival for patients with glioblastoma (n = 492) was 12 months, for patients with anaplastic astrocytoma (n = 83) 25 months, astrocytoma (n = 260) 95 months, oligodendroglioma (n = 85) 74 months, mixed glioma (n = 68) 65 months, and medulloblastoma (n = 53) 109 months. Median survival for patients with brain stem tumours (n = 37) was nine months, while 74% of patients with tumours in the pineal region (n = 38) survived for five years. The histology and localisation of the tumour, as well as age and functional status, are important prognostic factors for survival in patients with primary CNS tumours.

Adolescent↗

PubMed1996

Interactive image directed neurosurgery: patient registration employing the Laitinen stereo-adapter.

Fiducial markers visible on both imaging scans and the patient are a convenient and accurate method to register the patients head in stereotactic space preceeding an interactive image directed neurosurgical procedure. We have been using the Laitinen non-invasive relocatable stereo-adapter to carry the fidcucial markers both during the imaging and patient registration process. Since the adapter can be accurately remounted the surgical procedure can take place at any time interval after the imaging study. To compare registration accuracy studies were performed using a phantom carrying both surface fiducial markers and fiducial markers mounted on the stereo adapter. We have found that total system accuracy using either surface or adapter mounted markers and an optical tracking system is in the range of 3-5 mm and is acceptable for a broad range of neurosurgical applications.

Contrast Media↗

PubMed1996

Fractionated stereotactic radiation therapy for intracranial arteriovenous malformations.

Fractionation of radiotherapy is a radiobiological advantage because the radiation effects on healthy brain tissue are reduced. We used fractionated stereotactic radiotherapy for cerebral arteriovenous malformations employing a modified linear accelerator and a noninvasive stereoadaptor. The treatment was given in two sessions (1,400 cGy x 2). Control angiography at least 2 years after treatment was performed on 20 patients. The malformation was completely eliminated in 14 of 15 patients with small arteriovenous malformations. None of the 5 patients with large malformations had their lesion eliminated, but in 4 the malformation was significantly reduced. Fractionated stereotactic radiation therapy using a conventional accelerator is an effective and safe technique in the treatment of intracranial arteriovenous malformations and compares favorably to radiosurgery.

Adolescent↗

PubMed1996

Implementation of a stereotactic microscope using an optically coupled tracking system.

Image-directed neurosurgical systems allow the correlation of a point in the operative field to a corresponding point on the patient's CT/MR scans. We have modified a surgical microscope by mounting three light-emitting diodes (LEDs) on a small frame attached to the microscope. The operative field was registered to the MR scans by indexing four MR/patient visible fiducial points with a LED pointing device. To calibrate the microscope, the probe point was focused and centered in the microscopic field of view with the aid of cross hairs in the microscope ocular. The focal plane of the microscope could now be tracked in addition to the probe tip. During surgery the point of interest is centered in the cross hairs and brought into focus, and the corresponding point is indicated in three planar views on MR scans.

Brain Neoplasms↗

PubMed1993

Long-term results after percutaneous retrogasserian glycerol rhizotomy in patients with trigeminal neuralgia.

We have evaluated the long-term results of percutaneous retrogasserian glycerol rhizotomy (PRGR) in 60 patients with classical trigeminal neuralgia. Complete initial pain relief was achieved in 93% of the patients. Numbness was initially reported by 3/4 of the patients and at follow-up by 1/3, while long-lasting dysaesthesias were an important side effect in 38% of previously untreated patients. The half-life of the method was 47 months in our material, and this figure compares favourably with other previously reported series. The method carries a significant risk of long-lasting and troublesome sensory disturbances. Another disadvantage of the method, reported in the present long-term study, was the high incidence of recurrent neuralgia. We are unable to identify predictors of recurrent neuralgia after PRGR, although major recurrences were more common in patients with unchanged facial sensation postoperatively. In conclusion, PRGR offers safe and reliable relief of pain in patients with trigeminal neuralgia. In spite of the high incidence of recurrence and of long-lasting dysaesthesias it is, in our opinion, the method of choice in the elderly, and particularly suitable for patients at high risk.

Adult↗

PubMed1993

Prognostic factors in malignant gliomas with special reference to intra-arterial chemotherapy.

Survival was analyzed in 173 patients with malignant gliomas to study the importance of possible pretreatment prognostic factors. Seventy-nine of these patients received preirradiation intra-arterial chemotherapy with BCNU combined with vincristine intravenously and procarbazine orally; the others received only postoperative whole-brain irradiation. To judge by univariate and multivariate analyses the most important pretreatment prognostic factors were histology, corticosteroid dependency, pretreatment performance status and frontal lobe location of the tumors. Patients with anaplastic astrocytoma, not corticosteroid-dependent, with pretreatment performance status of 0-2 and with a frontal lobe location of the tumor seemed to benefit most from preirradiation chemotherapy.

Adult↗

PubMed1992

Combined intra-arterial chemotherapy followed by radiation in astrocytomas.

Seventy-five patients harboring astrocytomas received 4 cycles of infra-ophthalmic carotid injections of BCNU, combined with vincristine intravenously and procarbazine orally. All of the patients thereafter, received radiation therapy. The five year survival was 73% for all patients. The age of the patients had no significant impact on survival. The treatment results were compared with the results of 57 patients with astrocytomas who were treated with surgery followed by radiation in the same period. These 57 patients had a 5 year survival of 45% with a five year survival in patients < or = 40 years and patients > 40 years of 70% and 22%, respectively (p < 0.05). In multivariate survival analysis of the BCNU group and radiation group together, treatment group and corticosteroid dependency were the only prognostic factors. No leukoencephalopathy was seen during the treatment or in the follow-up of the patients. We conclude that pre-radiation intra-arterial chemotherapy can be given without significant morbidity and produces an improvement in survival in patients older than 40 years.

Administration, Oral↗

PubMed1992

Pre-radiation chemotherapy in glioma patients with poor prognostic factors.

Nineteen patients in an age group from 56-67 years (mean age 62.5 years) with histologically verified glioblastoma multiforme were treated with chemotherapy consisting of two cycles of oral CCNU, intravenous vincristine and oral procarbazine prior to radiation therapy. Ten of the patients had stable disease, monitored by CT scan and neurological examination, and received whole brain radiation. The median survival was 12 months. Nine patients who had progressive disease during chemotherapy did not receive radiation treatment and were put on palliative treatment with dexamethasone. This group had a median survival of 3 months. The median survival in all of the 19 patients who entered the study was 9 months which was comparable to the survival of 56 patients with glioblastoma multiforme who, in a retrospective study, received post-operative radiotherapy. The most important factor predicting survival was steroid-dependency after surgery.

Aged↗

PubMed1992

High incidence of serious side effects of high-dose dexamethasone treatment in patients with epidural spinal cord compression.

Twenty-eight consecutive patients were given high-dose dexamethasone (96 mg i.v. loading dose, decreasing doses to zero in 14 days) and radiotherapy for epidural spinal cord compression due to malignant disease. There were eight events classified as side effects of the dexamethasone treatment. Four of these were considered as serious (one fatal ulcer with haemorrhage, one rectal bleeding and one gastrointestinal perforation from undetermined origins, and one perforation of the sigmoid colon) giving a total rate of serious side effects of 14.3 percent. Due to the high incidence of serious side effects of the high dexamethasone dose, the regimen was abandoned in favor of a standard dexamethasone dose of 16 mg daily reduced to zero in 14 days. There were three events classified as side effects, but none were considered as serious in 38 consecutive patients receiving this dose. The differences both in total number of side effects and number of serious side effects are statistically significant. There was no significant difference in the number of ambulant patients in the group that received the high dexamethasone dose. We conclude that the high dexamethasone dose in our experience gives an unacceptably high incidence of serious side effects and we have therefore abandoned the regimen in favour of a more standard dexamethasone dose.

Aged↗

PubMed1992

Combined intra-arterial and systemic chemotherapy for recurrent malignant brain tumors.

Seventy-nine patients harboring recurrent brain tumors received four cycles of infraophthalmic carotid injections of 160 mg of carmustine. Two milligrams of intravenous vincristine and 50 mg of oral procarbazine was also administered three times daily for 1 week in conjunction with each BCNU treatment. The response rate was 60% with a median survival for patients with astrocytomas, anaplastic astrocytomas, and glioblastomas of 32, 20, and 6.5 months, respectively. The median survival of the responding patients was 20 months, and the survival at 30 months was 45%. The survival in patients not responding to treatment was 5 months, reflecting the natural history of the tumor. There have been no deaths related to the treatment procedure. No incidents of severe or permanent eye complications or leukoencephalopathy were observed. Based on multivariate survival analysis, only patients with a good performance status who are not steroid dependent are candidates for this treatment.

Administration, Oral↗

PubMed1992

Primary malignant lymphoma of the brain. A report of 24 cases from the Norwegian Radium Hospital.

Between 1975 and 1987, 24 patients with primary central nervous system lymphoma were seen and treated at the Norwegian Radium Hospital. The overall median survival was 24 months. Patients with poor performance status (WHO 3-4) had a median survival of 3 months whereas patients with good performance status (WHO 0-2) had a median survival of 40 months (p < 0.0001). Patients who were not steroid-dependent after operation had a better survival than those patients who were steroid-dependent (p = 0.02). Nine patients were still living without evidence of disease at last follow-up, 18-130 months after the initial treatment.

Adolescent↗

PubMed1992

99mTc-hexamethylpropyleneamine oxime leukocyte scintigraphy and C-reactive protein levels in the differential diagnosis of brain abscesses.

The demonstration and accurate localization of intracerebral mass lesions are commonly performed with computerized tomography (CT), which often cannot determine the nature of the lesion. As an aid in the differential diagnosis between brain abscess and neoplasm, the authors have evaluated both 99mTc-hexamethylpropyleneamine oxime (99mTc-HMPAO) leukocyte scintigraphy and the serum C-reactive protein level. Of 23 patients with intracranial mass lesions, 22 individuals showed ring-like contrast enhancement on CT scans; the one exception was a patient treated for a meningioma who had a negative CT scan despite clinical suspicion of intra- or extracranial abscess. The final diagnosis was invariably established by microscopic examination of tissue specimens. In 10 patients the final diagnosis was brain abscess; the other 13 patients harbored a brain neoplasm (glioma in nine, astrocytoma in one, and metastasis in three). The 99mTc-HMPAO leukocyte scintigraphy detected all cases of abscess. There were no false-positive results. An elevated C-reactive protein level (> 13 mg/liter) was found in all but one patient with abscess and in three patients with neoplasm; two of these three patients had dental root infections which could account for the elevation of C-reactive protein. It is concluded that 99mTc-HMPAO leukocyte scintigraphy should be performed when there is a possibility that a brain abscess may exist. Any steroid treatment should be discontinued for 48 hours prior to leukocyte scintigraphy. Also, C-reactive protein determination should be performed and is useful even when steroids are given.

Adolescent↗

PubMed1991

[Treatment of spinal cord compression caused by malignant disease].

Patients suffering from metastatic spinal cord compression can be treated with decompressive surgery and/or radiotherapy. The best treatment regimen remains to be established. In the present paper we report our experience of a therapeutic regimen with main emphasis on radiotherapy, but where selected patients were treated with laminectomy followed by radiotherapy. 67 patients were treated during a two year period, 60 with radiotherapy as the sole treatment modality. The ambulation rate after treatment was 56.7%. Degree of loss of neurological function before treatment and tumour histology were prognostic factors for a successful outcome, defined as the patient's ability to walk after treatment. We emphasize the importance of starting treatment before development of advanced neurological deficits.

Adolescent↗

PubMed1991

Combined intra-arterial chemotherapy and irradiation of malignant gliomas.

Seventy-nine patients with malignant gliomas (19 anaplastic astrocytomas and 60 glioblastoma multiforme) received 4 cycles of infra-ophthalmic carotid injection of 160 mg carmustine, 2 mg vincristine IV and procarbazine orally 50 mg 3 times daily for 1 week, followed by whole-brain irradiation, with a midpoint dose of 54 Gy/6 weeks. Response, judged by CT-scan, was seen in 31 out of 57 evaluable patients with a median survival of 30 months and 40% survival at 3 years. In all patients who responded to the treatment, a tumour regression was seen on CT-scan after chemotherapy before irradiation. In the 26 patients with progressive disease under chemotherapy, the median survival was 5 months. None of the patients who had progressive disease during chemotherapy had benefit from irradiation. The most important prognostic factors were good pretreatment performance status, glucocorticoid dependency and age. Few serious side-effects of the angiographic procedure were seen. Leukoencephalopathy was not observed in this study.

Adolescent↗

PubMed1990

Intra-arterial BCNU in the treatment of recurrent medulloblastoma.

Two patients with recurrent medulloblastomas were treated with combined oral and intravenous chemotherapy followed by intra-arterial BCNU. The 7 days course of oral and intra-venous chemotherapy consisted of CCNU and Procarbazin orally and Vincristine intravenously (PCV), repeated after 6 weeks. Intra-arterial chemotherapy consisted of 4 cycles of BCNU. Both patients responded well to treatment, evaluated by CT scans. One of the patients died of a new local recurrence 6 months after initiation of chemotherapy, whereas the other patient remains well, without CT evidence of tumour 36 months after the start of the treatment. No serious adverse side-effects related to the treatment were seen.

Adult↗

PubMed1990

Reversible oedema and necrosis after irradiation of the brain. Diagnostic procedures and clinical manifestations.

One hundred and twelve patients with primary brain tumour were followed every 3 months during and after brain irradiation and chemotherapy with brain scanning, EEG and neurological examination. Early delayed radiation reactions were seen in 6 patients. The symptoms developed 2-8 months after irradiation and lasted for 2-3 months. Two types of reactions were observed. One mild form appeared after 2-3 months and was characterized by low-attenuated expansive areas within the irradiated volume, without contrast enhancement on CT scan. Severe reactions appeared in some patients after 6 months, with exacerbation of earlier clinical signs and contrast enhancing lesions on CT. Regression of the CT finding was seen after 3 months. Recognition of this syndrome is important, as a new neurosurgical procedure might cause lasting neurological sequelae in patients who otherwise would recover without treatment.

Adolescent↗