Experimental cervical myelopathy: effects of compression and ischemia on the canine cervical cord

✓ Maximal tolerable compression was produced in 28 dogs by advancing a screw through the anterior portion of the C-5 vertebral body into the spinal canal until limb weakness occurred. Chronic vascular insufficiency was established in the cervical cord of 17 dogs by blocking or ligating the spinal and vertebral arteries and their branches in various combinations. Vascular insufficiency was also established in combination with maximal compression. Neurological, microangiographic, and histological findings in all groups of dogs were compared. Dogs in the last group with the most severe injury had more abnormal findings in surface vessels than did all other dogs. When the dogs were bled to the point of weakness, that point also appeared soonest in the last group. From these findings, the authors conclude that the effects of vascular insufficiency and compression are additive and that this may be an explanation of the clinical signs in patients with cervical spondylotic myelopathy who appear to have relatively slight mechanical compression.

Surgical experience with a microscopic transsphenoidal approach to pituitary tumors and non-neoplastic parasellar conditions

Improved surgical microscopes and intraoperative radiofluoroscopic television have revived the transsphenoidal approach to pituitary tumors. The transsphenoidal approach offers an alternative to craniotomy, and in certain situations it has distinct advantages. The reported experience includes the common pituitary tumors, hypersecreting microadenomas, cerebrospinal rhinorrhea and parasellar aneurysms. The surgical technique, indications and contraindications, and results in 44 transsphenoidal operations are described.

Cell kinetics of human gliomas

✓ Eleven selected patients with brain tumor were given 3H-thymidine intravenously at the time of operation. Parts of the excised tumor were fixed for routine histological studies as well as for simple radioautography. Other parts were minced immediately after excision and incubated at 37°C with 14C-thymidine, and were thus doubly labeled. Simple radioautography of the tumor specimen showed fairly even distribution of labeled cells in the astrocytoma group and uneven labeling of tumor cells in malignant gliomas, including glioblastomas. In most glioblastomas, the labeling index (percentage of cells labeled with 3H-thymidine) varied from near 0% in the necrotic areas to approximately 20% in the most viable parts of the same tumor; the labeling index of viable parts of the tumor ranged from 5% to 10% with the exception of astrocytomas in which the index was 1% or less. The duration of DNA synthesis ranged from 7 to 10 hours in the majority of tumors regardless of the nature or grade of malignancy.

Lack of correlation between clinical and angiographic findings in patients with brain tumors under BCNU chemotherapy

✓ Bis-chlorethyl-nitrosourea (BCNU) is one of the numerous experimental chemotherapeutic agents used to treat recurrent brain tumors. The clinical response and the angiographic changes in tumor vascularity were compared in 32 patients treated with BCNU for recurrent primary brain tumor. In five of 22 initially vascular lesions the tumor vasculature increased, in 11 it decreased, and in six it remained unchanged after treatment. There was no correlation between angiographic changes in the tumor and the clinical course following BCNU therapy.

Phase II study of 1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea (CCNU; NSC-79037) in the treatment of brain tumors

Thirty-eight patients with symptomatic recurrent primary or metastatic brain tumors were treated with 1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea (CCNU) at an initial dose of 120-130 mg/m2 with subsequent doses determined by the degree of delayed toxicity. The interval between treatments was usually 6 weeks. Two groups of patients were treated: those who had received no prior chemotherapy and those who had previously received BCNU. The response rates were 33% and 0 respectively. The major dose-limiting toxic effect was delayed depression of the white blood cell and platelet counts; this depression was not cumulative with the schedule used. Significant toxicity was encountered more frequently in the patients who had received BCNU previously. We concluded (a) that CCNU was effective against recurrent brain tumors although the results were not any better than those attainable with BCNU in a similar group of patients, and (b) that cross resistance to CCNU occurred in patients treated previously with BCNU.

Graded cryohypophysectomy in the rhesus monkey. Histopathology and endocrine function

✓ Histopathology and endocrine function of the pituitary gland of rhesus monkeys subjected to graded cryohypophysectomy were compared with the histopathology and endocrine function in hypophysectomized and sham-operated monkeys. Freezing at −50°, −100°, and −150°C destroyed 72.3%, 78.3%, and 93.1% of the pituitary respectively. The posterior lobe was more resistant to the damaging effects of cold. A nearly complete (96.3%) histological hypophysectomy was accomplished at −190°C; nearly all remaining viable tissue was in the posterior lobe. Freezing at −150°C appears to result in a complete functional hypophysectomy. Of the adenohypophyseal cells, the gonadotropin-secreting cells were the most susceptible to cold, with the growth-hormone-producing cells next in susceptibility. Adrenocorticotropin-secreting cells were more resistant. Cells producing thyroid-stimulating hormones were not susceptible, and the pituitary stalk was quite resistant to the damaging effects of freezing at these temperatures. Thus, a predictable partial hypophysectomy by means of cryosurgery seems feasible, and, with a predetermined time, it is evident that the degree of cold is critical in achieving a complete cryohypophysectomy.

Goodpasture's syndrome. Treatment with nephrectomy and renal transplantation

Three young male patients developed acute glomerulonephritis and serious hemoptysis. All three had evidence of antiglomerular basement membrane (anti-GBM) antibodies in their serum and native kidneys. The pulmonary hemorrhages ceased after bilateral nephrectomy and splenectomy accompanied by irregular treatment with steroids and other immunosuppressants. Renal homotransplantation was successfully carried out from 95 to 162 days later, after circulating anti-GBM antibodies had disappeared. Two of the homografts were biopsied and the third was removed 20, 34, and 2 months posttransplantation, respectively, and contained little or no immunoglobulin. Therefore, Good-pasture’s syndrome does not contraindicate renal transplantation under the stipulated conditions of staged therapy.

Glomerular basement membrane--reactive antibody in anti-lymphocyte globulin

Equine immunoglobulin was detected along the glomerular basement membrane of three human homograft recipients who had been treated with equine anti-lymphocyte globulin. Anti-lymphocyte globulins, given these patients, were obtained by immunization of horses with lymphocytes from human spleens and/or lymph nodes and contained glomerular basement membrane-reactive antibodies. Quantitative paired-label isotope experiments (in rats) demonstrated that 30-170 mug/ml of kidney-fixing antibodies were present in these preparations. The anti-lymphocyte globulins formed a line of identity with a sheep anti-human glomerular basement serum when reacted against collagenase-solubilized human glomerular basement membrane in double diffusion in agar. The renal fixation of these antibodies was blocked by absorption with human glomerular basement membrane, but not by buffy-coat leukocytes, indicating that they were directed specifically toward antigens in the basement membrane and were not cross-reacting anti-lymphocyte antibodies. Anti-lymphocyte globulin preparations for human use were studied for glomerular basement membrane-reactive antibodies by a direct immunofluorescent assay in rats. Anti-lymphocyte globulin from 13 of 20 horses, and 7 of 10 serum pools from horses immunized with lymphocytes derived from solid lymphoid organs (spleen, thymus, lymph node, tonsil), contained glomerular basement membrane-reactive antibodies. Sera from 18 horses injected with thoracic duct cells or cultured lymphoblasts had no glomerular basement membrane-reactive antibodies. An equine anti-human thymus serum containing glomerular basement membrane-reactive antibodies, which produced fatal glomerulonephritis in monkeys, was shown to cause both immediate and delayed glomerular injury in monkeys after intravenous injection. The reaction of this antibody with glomerular basement membrane in vivo was associated with little complement deposition in spite of the fact that the antibody could fix complement. This lack of glomerular complement fixation resulted from almost complete in vivo decomplementation of the monkeys receiving this anti-lymphocyte globulin.

Clotting changes, including disseminated intravascular coagulation, during rapid renal-homograft rejection

One of two patients in whom early homograft rejection developed after renal transplantation had many antidonor antibodies before operation. By the measurement of gradients across intracorporeal and extracorporeal homografts in this patient, the new kidneys were shown to sequester host immunoglobulins, platelets, white cells and clotting factors. Moreover, the renal venous blood then contained fibrinolytic activity. This presensitized recipient, as well as a second patient who did not have detectable preformed humoral antibodies, gave evidence from clinical observation and from the various clotting tests of disseminated intravascular coagulation with fibrinolysis and a severe bleeding, diathesis. Immunofluorescent and histologic studies revealed a laying down of fibrin in the homograft vessels that continued in some cases to cortical necrosis of the transplanted kidneys or, alternatively, receded at the time fibrinolysis occurred. The variety of rejection seen in these patients has been characterized as an immunologically induced coagulopathy.

Indications for hypophysectomy in diabetic retinopathy and cancer of the breast and prostate

Hypophysectomy can be advised for diabetic patients whose vision is threatened by neovascular changes characterizing proliferative retinopathy. In the management of advancing breast cancer, hypophysectomy is recommended in postmenopausal (natural or induced) patients who have received two trials of hormonal therapy. We advocate wider application of hypophysectomy for advancing prostate cancer, where, when used in sequence after castration and administration of hormonal therapy, it will relieve pain and produce tumor regression in some patients unresponsive to other forms of treatment. Transsphenoidal cryohypophysectomy is a safe and effective means of pituitary ablation.

Measurement of unit activity in various systems of the brain postoperatively; a preliminary study

Recording from single neurons in the human brain after head trauma was done through hair-like microelectrodes implanted during therapeutic operation. Types of responses were: (1) no unit activity; (2) unit activity in a random-like sequence; (3) multi-unit activity in synchronous rhythmic bursts and (4) unit activity at a more or less constant frequency. The method described here could be extended for use in any brain lesion where direct and quantitative postoperative information about the function of different neuronal populations is desired. This extremely sensitive test of neuronal function may be valuable in evaluating cerebral dysfunction in various clinical states, and as an indicator of imminent death. The latter assumes practical importance in patients who are potential donors of organs for transplantation. Continued research should confirm the value of this procedure.

The management of abdominal injuries in the presence of head injury

When head and blunt abdominal injuries are combined, the head injury is often afforded too much attention and the abdominal injury too little, especially when the patient is unconscious. If mismanaged, the abdominal injury is often the more serious threat to life. Except for extradural hemorrhage, neurosurgical intervention, when indicated, can be delayed until the patient has been thoroughly evaluated for the presence of extra cranial injuries with higher therapeutic priority. Abdominal examination of the unconscious or uncooperative patient is difficult. Tenderness as a sign of abdominal injury cannot be elicited. Abdominal rigidity (in the absence of rigid extremities), a silent abdomen, shock, and extreme restlessness may indicate intra-abdominal changes. Abdominal paracentesis is a valuable diagnostic aid, and the finding of blood, bile-stained fluid, intestinal contents or air is an indication for immediate laparotomy. Once all injuries are known, priorities for treatment can be assigned. Often head and abdominal injuries can be treated concomitantly.