C. Hunter Shelden

Immunotherapy for recurrent malignant glioma: an interim report on survival

We present interim survivial data, for a group of 83 adult patients with recurrent malignant glioma treated by implanting stimulated autologous lymphocytes into the tumour bed following surgical debulking. The patients were treated 6 months or more prior to data analysis. Fifty-nine patients were male and 24 female. The mean age for the entire group was 48.4 years and the mean Karnofsky rating (KR) was 67.2. Eight of the patients had grade II tumours, 33 had grade III tumours and 42 had grade IV tumours. Statistical analysis focuses on tumour grade, KR and patient age, factors that have been shown to affect survival in previous studies. Multifactorial analyses are employed to identify interrelationships among factors related to survival. Seven patients (8%) did not respond to immunotherapy, 76 (92%) had a good initial response. Twenty-five patients (30.1%) are living and 18 (22%) have shown no evidence of recurrence. Results are evaluated in the light of those obtained in trials of other experimental therapies for recurrent malignant gliomas. It is concluded that the present protocol offers a safe and comparatively effective treatment option.

A new approach to inoperable craniopharyngiomas

The surgical treatment of craniopharyngiomas is extremely difficult. Initial complete surgical removal is seldom accomplished, and a recurrent tumor can never be totally removed without severe endocrine, visual, or other serious residua. The craniopharyngioma is benign histologically, sellar and suprasellar in location, cystic in appearance, and it contains brownish fluid flecked with refractile cholesterol crystals. The suprasellar position of the major portion of these large tumors accounts for the early encroachment on the hypothalamus and optic nerves. The most effective operative procedure is transfrontal craniotomy with an intradural approach along the roof of the orbit to the optic nerve and tumor. At the time of the initial operation the

Nuclear magnetic resonance imaging: Review of early clinical experience☆

Nuclear magnetic resonance tomography is a powerful new imaging modality which produces cross-sectional images similar to those obtained by computerized tomography. However, unlike computerized tomography, nuclear magnetic resonance imaging does not use ionizing radiation but rather utilizes an apparently safe interaction between magnetic fields, radio waves, and atomic nuclei. Basic principles of nuclear magnetic resonance imaging are discussed briefly and promising early clinical applications are reviewed. The two magnetic relaxation times, T1 and T2, provide discrimination between tissues based on differences in fat and water content. Tumors are readily differentiated from normal tissue on the basis of the increased water content, primarily due to edema and hypervascularity. Although nuclear magnetic resonance imaging is very sensitive in the detection of these abnormalities, it is not yet able to provide a specific diagnosis.

Development and clinical capabilities of a new implantable biostimulator

Abstract During the past nine years we have used experimentally and clinically various types of implantable electronic units to stimulate or block nerve impulses. Tissue tolerance and reliability have been excellent, but electronic design and production factors limited their versatility. Our recent studies, a part of the visual prosthesis program, revealed the importance of a need for a device with the capability of receiving a wide variety of signals. The type of current, wave form, pulse width, and frequency have proved to be of critical importance and the available devices cannot meet these demands. Our experiments have shown that for chronic electrical stimulation or inhibition of nervous tissue the most critical factor is “current density” at the point of contact. Heat production and impedance are other important considerations. The unit discussed has been designed and built to allow precise control of these parameters. Until recently the only neurosurgical methods to alter function of the nervous system were destruction of a given area or interruption of nervous pathways. In selected situations this has been effective but, generally, an associated loss of either motor or sensory function results. Electronic methods hold promise for selective or partial alteration of function that can be programmed according to a temporal schedule. An area can now be stimulated or blocked without local destruction. By controlled stimulation, information can be fed into the system which may alter the subjective response and the nature of the reflex arc, or even amplify cerebral inhibition. Using multiple circuits one structure can be stimulated while function in an adjacent area can be inhibited. The clinical application of the system is discussed with particular reference to the electronic control of pain secondary to malignant disease. A brief discussion is given regarding the probable origin of pain and how involved pathways can be altered electrically. Future clinical applications are mentioned.

Adverse effects of electrical energy applied to the nervous system.

Neural prostheses activated by radiofrequency transmission are currently being implanted to treat a variety of clinical problems. It is essential that neither the materials used in these prostheses, particularly the electrodes, nor the stimulus parameters that are employed will cause neural damage. The experiences of investigators engaged in both the experimental laboratory and clinical studies of the effects of electrical stimulation are reported herein.

Computerized Microstereotactic Neurosurgical Endoscopy Under Direct Three-Dimensional Vision

Computerized tomography (CT) and magnetic resonance imaging (MRI) have given neurosurgeons the opportunity to visualize intracranial lesions much earlier than was heretofore possible with more invasive techniques. Continued improvement in image resolution has led to the diagnosis of intracranial lesions that are too small to be located and removed by conventional methods. In this chapter, we describe our stereotactic method, including carbon dioxide laser vaporization, for the removal of small central nervous system (CNS) lesions under three-dimensional visual control.

New method of closure of the scalp.

A n y m e t h o d of closure of the scalp has two essent ia l f a c t o r s a p p r o x i m a t i o n of the marg ins of the wound and a d e q u a t e hemostas is . The twol aye r m e t h o d e m p l o y i n g silk su tures was the accep ted s t a n d a r d for m a n y years . In 1943, while in the N a v y , we began to use an inve r t ed m a t t r e s s su ture of t a n t a l u m wire for closure of the scalp. Th is m e t h o d was more rap id , allowed b e t t e r hemostas i s , and , when removed , lef t no foreign m a t e r i a l in the wound. Stainless steel wire has since rep laced t a n t a l u m b u t the m e t h o d of use and a d v a n tages are s imilar .