Intrathecal injection of a specific enzyme in rats as a model for chemically induced spinal cord injury

A spinal cord injury model is described using chymopapain as a neurotoxic agent in rats. The trauma was evaluated by neurophysiological and morphological methods. Electrically evoked compound action potentials were used to quantify the neurophysiological effects caused by the injection of chymopapain into the lumbar dural theca in rats. A branch of the sciatic nerve was stimulated with voltage impulses of constant amplitude (40 V) and duration (0.1 ms) at the right external malleolus. The responses were recorded at the dorsal root entry zone L1. We used different doses of the enzyme (1000 i.u./ml; 2500 i.u./ml; 5000 i.u./ml). A total amount of 0.1 ml was injected into the rats' lumbar spinal canal intrathecally (n = 18). The control rate (n = 8) were subjected to exactly the same stimulus and recording procedures but the test solution was a corresponding volume of isotonic saline. Two hours after injection the animals were examined clinically and then sacrificed for histology. The prolongation of the latency of the electrically evoked potentials caused by the enzyme was very clear at the doses of 2500 i.u. and 5000 i.u. being about 10-15% relative to the mean latency before administration of the drug. The histological evaluation showed hemorrhage, vascular damage and indirect signs of myelin edema of the lumbar nerve tissue. Our study indicates that chymopapain injections into the lumbar spinal canal can be used as a reproducible model for spinal cord injury research.     

Intraluminal thrombosis and growth-mechanism of giant intracranial aneurysms

12 giant intracranial aneurysms were studied by MRI. Intraluminal thrombosis was observed in 9 aneurysms. Thrombosis was found more frequently in larger aneurysms. Thrombi were formed posteriorly or inferiorly in the lumen of 4 among 5 IC-cavernous aneurysms. Location of the neck of the aneurysms and stagnation of blood flow influenced by gravity may be causative factors determining the location of thrombi. In 6 aneurysms intraluminal thrombi were inhomogeneous on MRI, suggesting that the thrombi had been formed at different times. New thrombi were formed between the aneurysmal wall and the old thrombus in 3 cases. Dissection of the aneurysmal wall by residual blood flow in the lumen or hemorrhage in the aneurysmal wall may be one of the growth mechanisms of giant intracranial aneurysms.     

Glycerol-induced acute renal failure in the rat: the protective effect of unilateral nephrectomy

Studies were performed to evaluate the effect of unilateral nephrectomy on glycerol-induced acute renal failure in the rat. Normal rats were subjected to either sham uninephrectomy (n = 43) or right uninephrectomy (n = 53). The functional compensation of the remaining kidney was followed after 1 and 2 weeks. Fourteen days after the operation, acute renal failure was induced by injection of 50% glycerol solution to both groups. Uninephrectomised rats developed a lesser degree of renal failure compared to sham-operated rats. Forty-eight hours after glycerol injection, PCr of uninephrectomised rats was 260 +/- 22 mumol/l compared with 338 +/- 26 in sham-operated rats (P less than 0.0125) and CCr in uninephrectomised rats was greater (0.10 +/- 0.01 ml/min vs 0.07 +/- 0.01; P less than 0.025) in sham rats. Uninephrectomised rats had significantly greater recovery of CCr compared to sham rats at 24 h (20.1% +/- 2.3 vs 13.1% +/- 2.2, P less than 0.025) and at 48 h (32.1% +/- 3.3 vs 19.2% +/- 3.3, P less than 0.005) after glycerol injection. FENa was significantly less in uninephrectomised rats: 0.96 +/- 0.16% vs 2.25 +/- 0.05% (P less than 0.025) in sham rats 24 h post glycerol. Urinary excretion of K+ was greater in rats following uninephrectomy compared to sham rats both after 24 h and 48 h post glycerol (P less than 0.01), accompanied by lower plasma potassium (P less than 0.05). A correlation coefficient (r) of 0.793 was observed between urinary potassium excretion rate and percentage recovery of CCr.(ABSTRACT TRUNCATED AT 250 WORDS)     

The importance of intraoperative cholangiography during laparoscopic cholecystectomy

Laparoscopic cholecystectomy (LC) using electrocoagulation was successfully performed in 56 out of 58 selected patients. Cholangiography was performed in 53 patients. Six patients had common duct stones; five were unsuspected preoperatively. After the gallbladder was removed, three patients underwent open common duct exploration. In another five cases, anatomical anomalies were discovered. Cholangiography performed via the cystic duct before any structures are divided can prevent the most serious complication--common duct injury. Cholangiography should be attempted on all patients undergoing LC.     

Diagnosis of deep vein thrombosis by high resolution ultrasonography

Using high resolution ultrasonography (US), diagnostic accuracy of thrombi in each venous segment of lower limbs and qualitative evaluation of thrombi in deep vein thrombosis (DVT) were investigated. The subjects were 106 lower limbs in 81 patients. The thrombi in common femoral vein (CFV), were diagnosed by compression technique and, were qualitatively analysed by echogenicity and consistency. Venography was performed in 18 limbs and histologic tests of thrombi were made in 6 limbs. The total accuracy of US was 100% for diagnosis of DVT, but was 83% for diagnosis of its extent. The total accuracy of US in each segment was greater than 90%, but the sensitivity of iliac veins was less than 90%. The thrombi in CFV were divided into 3 types and 8 sub-types. Type A was homogenous, type B was heterogenous, and type C was contracted echo. The types of us were consistent with results of histologic tests. We concluded that high resolution US is available for screening test for diagnosis of DVT and that qualitative evaluation of thrombi by US is a useful clinical test for selection of more adequate treatments.     

Spinal anaesthesia in a child with Job''s syndrome, pneumatoceles and empyema

We present a case of acute bowel obstruction in an immunocompromised child, who also had lobar pneumonia and a giant unilateral pneumatocele. She was successfully managed with subarachnoid anaesthesia for exploratory laparotomy to relieve a colonic obstruction. This proved to be a safe alternative to general anaesthesia with tracheal intubation in this patient and should be considered in infants and children in selected cases whenever a contraindication to general anaesthesia exists.     

Nonocclusive mesenteric ischemia in renal patients: recognition and prevention of intestinal gangrene

Nonocclusive mesenteric ischemia (NOMI) is a disorder with an extremely high mortality. Salvage of affected patients requires early recognition and aggressive intervention to prevent intestinal gangrene. Dialysis patients represent a group at particularly high risk for this condition. Clinicians should develop a high index of suspicion for NOMI in dialysis patients to lessen the risk of death. A high interventional posture must be maintained due to the notoriously unreliable signs and symptoms of this disorder.     

Large colloid cyst in lateral ventricle simulating brain tumour

Summary This case report describes a patient presenting with symptoms of increased intracranial pressure, whose computerized tomographic (CT) scan was highly suggestive of a large low-grade glioma invading the basal ganglia. Magnetic resonance imaging (MRI) revealed a well-demarcated space-occupying mass of increased intensity in the left lateral ventricle and adjacent white matter. Following stereotactic biopsy, which yielded a homogeneous jelly-like material, the mass was removed microsurgically and was found to be most like a colloid cyst on histological examination. Discussion focusses on the clinical and differential diagnostic implications of this very unusual combination of findings.     

Legg-Calvé-Perthes disease in hemophilia: incidence and etiologic considerations

A review of hip radiographs of patients with severe hemophilia showed Legg-Calvé-Perthes disease in four of 63 patients examined before the era of specific treatment. In another series of 44 patients receiving prophylactic treatment, there was no evidence of Legg-Calvé-Perthes disease. A case report of a boy with severe hemophilia with hip joint bleeding that caused joint capsule distention and greatly increased intracapsular pressure is presented. Based on our findings, and previously published results, we suggest that Legg-Calvé-Perthes disease in hemophilia is caused by increased intracapsular pressure secondary to hemarthrosis.     

Malignant schwannoma of acoustic nerve: a case report

During a routine physical examination in 1976, a 54-year-old man was noted to suffer from hearing difficulty and continuing tinnitus of his right ear. He had, however, no further consultations for the next five years, although the symptom persisted and gradually worsened. In May 1981, he experienced complete hearing loss in his right ear. A computed tomography disclosed no abnormalities, and other laboratory tests were unremarkable. In September 1981, the patient began to complain of paresthesia of the right angle of the mouth and tongue, right-sided facial paralysis, and walking difficulty. A repeated computed tomography showed a tumor at the right cerebellopontine angle region. A clinical diagnosis of acoustic schwannoma was made. The first operation was performed in December 1981. Complete removal of the tumor was impossible because of its unexpected, unusual hardness. The pathologic diagnosis was a malignant mesenchymal tumor, compatible with a malignant nerve sheath tumor of the acoustic nerve. A second operation was performed in January 1982, but the rapid postoperative regrowth of the tumor necessitated a third operation in March 1982. The patient died in the next month. Family histories did not show any evidence of von Recklinghausen's disease, and neither did the patient have any clinical stigmata of this disease.