Stereotaxic Apparatus Research Articles

The bony tentorium of the cat: stereotaxic coordinates.

The cat's tentorium cerebelli is an osseous structure which overlies much of the brain stem. None of the current brain atlases list the coordinates of this bony projection. With a stiff wire and a stereotaxic apparatus, the location of its free edge and dorsal surface was mapped in 1.0 mm steps in the skulls of 16 cats. In the midline the dorsal surface meets the calvaria at a point 7 mm posterior and 15 mm superior to the atlas zero (intra-aural plane + 10 mm horizontal). From this junction it slopes inferiorly and anteriorly between the cerebrum and cerebellum along a 50 degree slope to terminate along a curved line. In the midline this free edge is located 0.5 mm anterior, and 6.5 mm superior to the atlas zero. It recedes laterally along a curved line to a point 6 mm lateral, 6 mm superior and 3 mm posterior to the atlas zero. The free edge then curves forward and descends to pass through an imaginary line 3 mm anterior and 4.5 mm inferior to the altas zero. Statistical comparisons between measurements made in male and female cats revealed no significant differences.

A stereotaxic apparatus for the young rat

A stereotaxic apparatus for young rats is described. Fixation pieces are simple, producing no trauma. They assure precision for stereotaxic studies and chronic implantation of electrodes.

A stereotaxic atlas and technique for forebrain nuclei of the goldfish, Carassius auratus.

AbstractA stereotaxic apparatus and technique for electrode placement in forebrain nuclei of the goldfish is described. An atlas of forebrain nuclei is given. Some new nuclear regions are described and the nomenclature of several nuclei is discussed.

A stereotaxic atlas and technique for forebrain nuclei of the killfish, Fundulus heteroclitus.

AbstractA stereotaxic apparatus and technique for electrode placement in forebrain nuclei of the killifish, Fundulus heteroclitus, is described. An atlas of forebrain nuclei is given. A new nuclear region in the telencephalon is described.

Stereotaxic Apparatus for Operations on the Human Brain

Purpose: Head and neck cancer (HNC) is the sixth most common cancer worldwide with a 5-year survival rate of less than 50%. The PI3K/AKT/mTOR signaling pathway is frequently implicated in HNC. Recently, IQ motif–containing GTPase-activating protein 1 (IQGAP1) was discovered to scaffold the PI3K/AKT signaling pathway. IQGAP1 gene expression is increased in HNC, raising the hypothesis that IQGAP1 contributes to HNC. Experimental Design: We performed a combination of in vitro studies using human cancer cell lines treated with a cell-permeable peptide that interferes with IQGAP1′s ability to bind to PI3K, and in vivo studies utilizing mice genetically knocked out for the Iqgap1 (Iqgap1−/−). In vivo EGF stimulation assays were used to evaluate PI3K signaling. To study the role of IQGAP1 in HNC, we used a well-validated mouse model that drives HNC via a synthetic oral carcinogen, 4-nitroquinoline 1-oxide (4NQO). Results: IQGAP1 is necessary for efficient PI3K signaling in vitro and in vivo. Disruption of IQGAP1-scaffolded PI3K/AKT signaling reduced HNC cell survival. Iqgap1−/− mice had significantly lower cancer incidences, lesser disease severity, and fewer cancer foci. IQGAP1 protein levels were increased in HNC arising in Iqgap1+/+ mice. The level of PI3K signaling in 4NQO-induced HNC arising in Iqgap1−/− mice was significantly reduced, consistent with the hypothesis that IQGAP1 contributes to HNC at least partly through PI3K signaling. High IQGAP1 expression correlated with reduced survival, and high pS6 levels correlated with high IQGAP1 levels in patients with HNC. Conclusions: These data demonstrate that IQGAP1 contributes to head and neck carcinogenesis.

New headholder for sensory stimulation and stereotaxic operations in small animals

A new type headholder for laboratory animals is described. The animal's head is fixed by a nose-clamp pressing its upper teeth to a mouth-plate. The surface of the skull is left entirely free for the purpose of experimental work. The headclamp can also be connected to stereotaxic apparatus.

ISAH: a versatile treatment positioner for external radiation therapy.

Mechanical features, control philosophy, and operational characteristics are described for the computer-controlled patient positioner, „ISAH'' (Irradiation Stereotaxic Apparatus for Humans). The positioner is currently being used with the 910-MeV helium-ion beam from the 184” Cyclotron at the Lawrence Berkeley Laboratory. It is capable of positioning a patient to 0.1-mm accuracy in three dimensions. It can simultaneously or selectively translate the patient in three orthogonal axes and rotate him about two perpendicular axes. ISAH is used to deliver a therapeutic dose of radiation to an arbitrarily determined volume within the patient's body during irradiation, so as to minimize exposure to surrounding tissues. The motions are under online control by a PDP-8/1 computer which directs the necessary motions and verifies the positioning. The computer also controls the intensity and the depth of penetration of the heavy-ion beam.

Changes in striatal da metabolism induced by cholinergic and anti-cholinergic nigral stimulation in the rat

Publisher Summary This chapter discusses the changes in striatal dopamine (DA) metabolism induced by cholinergic and anti-cholinergic nigral stimulation in the rat. Experiments were performed on male Charles Rivers rats positioned in a stereotaxic apparatus, and anesthetized with a mixture of halothane, oxygen and nitrousoxide. The rate of DA disappearance after inhibition of the amine synthesis with RO 4-4602 was used as an index of the rate of striatal utilization. Such a treatment induces a decrease in striatal DA levels within 30 min when compared to untreated rats. It is found that when carbachol was applied in the SN 15 min after the injection of RO 4-4602, striatal DA levels in the treated side were 15% higher than those of the sham operated side. In contrast after atropine treatment DA disappearance was enhanced, because DA levels in the ipsilateral side were significantly lower than those of the contralateral NCP. These effects observed in a short-time interval suggest that DA utilization in the NCP was counteracted by carbachol and stimulated by the atropine nigral infusion.

Closed chamber for recording from single units in the dorsal column nuclei

Recording from single units requires a stability which is difficult to achieve for dorsal column nuclei. Prolonged records have been obtained by a stabilization method using a closed chamber that is not attached to the bone but to the frame of the stereotaxic apparatus.

Site of action of diazepam in the prevention of lidocaine induced seizure activity in cats.

Small volumes of diazepam were placed at a variety of sites within the central nervous system of cats, using a stereotaxic apparatus. The ability of diazepam so applied to prevent intravenous lidocaine induced seizures was most marked at brain stem reticular formation.

First stereotaxic apparatus created by Russian scientists in the 19th century

First stereotaxic apparatus created by Russian scientists in the 19th century

Placing the head horizontally in the stereotaxic apparatus by using X-ray photographs

A method is described for a more exact horizontal placement of the head in a stereotaxic apparatus by superimposing an X-ray photo of the head on one of a grid under the same experimental conditions. This method increases the accuracy of positioning of the needle electrodes subsequently used.

Stereotaxic apparatus and operations in Russia in the 19th century.

✓ The authors trace the early history of human stereotaxic apparatus and its use with particular reference to the work of D. N. Zernov in 1889, N. V. Altuchov in 1891, and G. I. Rossolimo in 1907, as well as the better known apparatus described by Horsley and Clarke in 1906.

A simple and inexpensive stereotaxic apparatus.

A stereotaxic apparatus is described which is built from commercially available machine tool parts with a minimum of machining and expense. Placement of either electrodes or needles for injections can be carried out in the brain or spinal cord of cats, or other animals of similar size, with a precision of ±0.05 mm.

A device for the easy administration of volatile anesthetics to rats undergoing stereotaxic surgery

Conventional procedures do not provide a practical method for the administration of volatile anesthetics such as halothane to rats while they are undergoing stereotaxic surgery. This paper describes a device which meets this need and which is easy and inexpensive to construct. A two-piece cylinder cut from the mouth of a polyethylene bottle forms a closed system around the muzzle of a rat and does not interfere with the stereotaxic apparatus or with the operation itself. The cylinder is attached to any standard device for the dispension of volatile anesthetics. The immediate advantage is that behavioral assesaments can be made relatively soon after surgery.

A simple procedure for making stereotaxic lesions in the mouse

A simple device for making stereotaxic brain lesions or administering electrical brain stimulation in the mouse, without placing the mouse in a stereotaxic apparatus, is described. The entire operative procedure takes approximately one min.

New apparatus for spinal cord stereotaxis and its use in the microsurgery of lumbar enlargement.

Our construction of the spinal cord stereotaxic apparatus is different from similar apparatus available. The base of the apparatus is attached directly to the arc of the vertebral body by means of a handle screw. The apparatus is light, easily demontable. Movement is possible in 3 perpendicular plains and carries one fine uni- or dipolar electrode. By means of this electrode the spinal cord potentials are recorded, the spinal cord structures can be stimulated and lesions are carried out by electrocoagulation. The target can be reached according to model maps of the spinal cord. The apparatus is used in order to influence the hyperspastic bladder and the spasticity of the lower limbs after interruption of the spinal cord. Results are encouraging us to use the stereotaxic method for the treatment of neurogenic bladder in the spinal cord segment S<sub>2</sub>.

A Stereotaxic Atlas of the Opossum Brain <i>(Didelphis virginiana)</i>; pp. 133–150

A stereotaxic atlas of the Virginia opposum <i>(Didelphis virginiana) </i>was developed. A cat stereotaxic apparatus (Baltimore Instruments, Inc.) was used.The study included the area of the brain between the septum and the mesencephalon. Particular emphasis wasplaced on the structures of the diencephalon. Two reference points on the skull are given to check the position of the brain in the stereotaxic apparatus. The map was found to be highly accurate when used in electro-physiological studies of the hypothalamus.

A Stereotaxic Atlas of the Opossum Brain &lt;i&gt;(Didelphis virginiana)&lt;/i&gt;; pp. 114–132

A stereotaxic atlas of the Virginia opposum (Didelphis virginiana) was developed. A cat stereotaxic apparatus (Baltimore Instruments, Inc.) was used.The study included the area of t

An oriented plastic slicing guide for facilitating stereotaxic interpretations in brain sections.

A rigid plastic cutting guide for whole brains in which the interior conforms to the contours of the interior base of the cranial cavity was molded from plastic that sets at room temperature. The mold was poured in a glass staining dish surrounding a wax-coated plaster cast of the floor of the skull. Both the casting and the molding processes were carried out in a stereotaxic apparatus to insure proper alignment. The molded box supports the brain in correct stereotaxic alignment, and vertical slits sawed at 5 mm intervals along the width of the box allow the passage of a blade through the brain. The resulting tissue slabs are of uniform thickness and can be easily correlated with the coronal planes shown in stereotaxic atlases. This inexpensive cutting device reduces the number of thin sections lost between tissue blocks, an important consideration when tracking degenerating nerves.