Quantitative measurement of the basilar arterial flow in the dog-electromagnetic flow-meter study of the extra-and intracranial arterial occlusion (author's transl)]

Recent advances in microneurosurgery have markedly improved the result of surgical treatment of aneurysm and arteriovenous malformation in the posterior cranial fossa. However, more precise study on hemodynamics of the vertebro-basilar system may be necessary for further progress in treatment of the vascular lesions. From this point of view, the authors studied the basilar arterial flow of the dog by means of an electromagnetic flow-meter and the flow probe which was specially devised by the authors. (1) The ratio of absolute value of the mean basilar flow to the total brain weight was calculated, and the flow rate was expressed in ml/100 g brain/min. Mean value was 7.1 ml/100 g brain/min under normocapnea. (2) The effect of occlusion of the common carotid, of the external carotid, of the intracranial internal carotid, and of the extracranial internal carotid on the basilar flow was less remarkable in this order. (3) Under normocapnea, occlusion of the unilateral common carotid artery produced 115% increase in the basilar arterial flow. Bilateral common carotid occlusion resulted in 312% increase of the flow, demonstrating a remarkable ability of compensation of the basilar artery through the circle of Willis and leptomeningeal anastomoses. Under hypercapnea, unilateral common carotid occlusion was followed by 81% increase in the basillar flow. Occlusion of both common carotids caused 230% increase in the basilar flow. Percent increase in the basilar flow after unilateral or bilateral common carotid occlusion under normocapnea was significantly larger than under hypercapnea (p less than 0.05 and p less than 0.01 respectively). It may be supposed that under normacapnea the increased basilar flow following bilateral common carotid occlusion may compensate the decrease in total cerebral blood flow due to carotid occlusion. However, the compensatory rise in the basilar flow under hypercapnea may be not enough to supply the dilated vascular bed in the carotid and basilar territories. There might be even a risk of deficiency of blood supply in the territory of the basilar artery, if the vascular resistance in the carotid area could become less than that in the basilar. The significance of CO2 inhalation therapy for ischemic cerebral lesion was discussed. (4) After the both common carotid arteries were occluded, the basilar aretry was clamped temporarily. Following release of basilar occlusion, reactive hyperemia was observed in the basilar flow. Magnitude and duration of the reactive hyperemia increased progressively depending on duration of the basilar occlusion to some extent. The phenomenon may be best explained by a progressive accumulation of vasodilating metabolities in the ischemic area. (5) Unilateral vertebral occlusion caused 37% decrease in the basilar flow. Bilateral vertebral occlusion resulted in reverse of the basilar flow, averaging 61% of the original value in flow rate. (6) Occlusion of the unilateral subclavian artery produced "subclavian steal phenomenon"...     

Thallium-201 single photon emission tomography of intracranial angiomas

We herein describe thallium-201 single photon emission tomography (T1-201 SPECT) findings in three cases with intracranial angioma. One of the lesions which was associated with chronic encapsulated intracerebral hematoma showed moderate accumulation of T1-201, but, others demonstrated no accumulation. The usefulness and limitations of T1-201 SPECT in differential diagnosis of intracranial mass lesions are discussed.     

Real-time monitoring of glutamate following fluid percussion brain injury with hypoxia in the rat

In the present study, extracellular glutamate (Glu) was monitored in real time using an enzyme electrode biosensor following traumatic brain injury (TBI) either with or without inducing hypoxia in the rat. We also measured the cortical contusion volume at 3 days after insult by staining with 2,3,5-triphenyltetrazolium chloride (TTC). Male Sprague-Dawley rats (300-400 g) were anesthetized and then subjected to lateral fluid percussion (FP) brain injury of moderate severity (3.5-4.0 atm), using the Dragonfly device model (no. HPD-1700). The experimental animals were divided into four groups. Group 1 (n = 10) was subjected to TBI only, group 2 (n = 10) to TBI followed by 20 min of moderate hypoxia (FiO2: 10%), group 3 (n = 4) to 20 min of moderate hypoxia without TBI, and group 4 (n = 4) to sham. Seventy-two hours after the insults, the animals were sacrificed, their brains were stained with TTC, and the lesion volumes were calculated. A surge in the extracellular Glu concentration occurred immediately after TBI in groups 1 and 2. There was no significant difference between the two groups. Group 2 showed a prolonged efflux of Glu during hypoxia ( < 0.05). In group 3, Glu continued to show a mild increase. The cortical contusion volume in group 2 was significantly larger than that in group 1. To evaluate the possible involvement of apoptosis in groups 1 and 2, separate rats were sacrificed under the same procedures after 1, 6, 24, and 72 h after insult (n = 2/group). Immunohistochemical analysis demonstrated an increased number of both the cysteine protease caspase-3-positive cells at 24 h and TUNEL-positive cells at 72 h in group 2. These results suggest that TBI with moderate hypoxia induced the prolonged efflux of Glu, which thus resulted in more cortical damage due to necrosis and apoptosis.     

Early Experiences of Haemostasis on Brain Tumour Surgery with Argon Plasma Coagulation (APC)

Summary  Objective. We first applied a novel haemostatic strategy involving Argon Plasma Coagulation (APC), an innovative no-touch electrocoagulation technique in which a high-frequency alternating current is delivered to the tissue through ionized argon gas, to brain tumour surgery, and report its usefulness and limitations.  Methods. The APC system we used comprised an APC 300 developed by ERBE Elektromedizin GmbH, Germany. We applied APC to 13 brain tumours in 12 patients (5 meningiomas, 4 sarcomas, 2 glioblastomas, and 2 pituitary adenomas). To avoid unnecessary thermal injury to the tissue as much as possible, power/gas flow settings of 20 and 40 W were used. The impact time was varied individually but was around several seconds per one impact. The argon jet (1.5–4.5 L/min) clears a field of pooled blood and evenly conducts electrical energy to the target tissue. A thin and flexible probe particularly increased the usefulness of APC for haemostasis on deep-seated skull base tumour operations under a microscope.  Conclusion. All patients were successfully treated and satisfied with the surgical results without any complications due to APC. APC appears to be an excellent alternative strategy for achieving haemostasis on vascular-rich brain tumour surgery, and may be valuable for the management of patients with coagulation defects.     

Glial-derived growth factor signaling pathway in infantile hypertrophic pyloric stenosis

BACKGROUND/PURPOSE: Glial-derived growth factor (GDNF), which is the ligand of RET is reported to be essential for the development of enteric nervous system. A GDNF knockout mouse model has shown that the gastric region is a critical passing site between GDNF-RET-independent neuroblasts (colonizing the esophagus) and GDNF-RET-dependent neuroblasts (colonizing the small and large bowel). The earliest GDNF site of production is the mesenchyme and the outer smooth muscle cell (SMC) layer of the developing bowel. In the mature gastrointestinal tract the presence of GDNF is restricted to enteric glial cells. The aim of this study was to investigate the expression of GDNF and RET in infantile hypertrophic pyloric stenosis (IHPS). METHODS: Full-thickness muscle biopsy specimens were obtained from 8 IHPS patients at pyloromyotomy and from 8 age-matched controls without gastrointestinal disease. Indirect immunohistochemistry was performed using avidin-biotin-peroxidase complex method with anti-GDNF and anti-RET antibodies. Quantitative analysis was performed using sandwich-type enzyme-linked immunosorbent assay (ELISA) for GDNF. RESULTS: GDNF- and RET-positive nerve fibers were absent or markedly reduced in IHPS compared with controls. GDNF was expressed strongly by smooth muscle cells of both muscular layers in IHPS, whereas no GDNF expression was detected in pyloric muscle of controls. The quantity of total GDNF in IHPS was significantly higher than in controls (P < .01). CONCLUSIONS: The lack or markedly decreased number of GDNF-positive nerve fibers in IHPS supports the hypothesis of a selective immaturity of the enteric glia in the muscular layers in IHPS. The strong expression of GDNF in smooth muscle cells in IHPS and the increased levels of GDNF in IHPS suggest a compensatory mechanism by which the smooth muscle cells continue to produce GDNF until maturation of the enteric glial cells occurs.     

Multiple gastrointestinal atresias result from disturbed morphogenesis

 Multiple gastrointestinal atresias (MGA) have been reported to account for 6% to 32% of all intestinal atresias. Controversy exists regarding the pathogenesis. Many investigators believe MGA to be the result of multiple ischemic infarctions of the intestinal tract. However, some have suggested that MGA results from a malformative process early in fetal life. Prenatal exposure to adriamycin in a rat model has been reported to lead to a spectrum of tracheoesophageal and associated malformations of the gastrointestinal tract, including intestinal atresias, identical to these observed in humans. The aim of this study was to determine the incidence and histopathologic findings of MGA in order to understand the pathogenesis. Timed-pregnant Sprague-Dawley rats were injected with adriamycin (1.75 mg/kg) in nine different gestational-day protocols. MGA was only seen in those rats who received adriamycin on gestational days 7, 8, and 9. The litters were recovered on day 21 by cesarean section. The digestive tracts (DT) of the fetuses were harvested for macroscopic and microscopic examination. Ten rats who received adriamycin on gestational days 7, 8, and 9 produced 87 newborns; 1 was damaged during dissection. DT anomalies occurred in 80 (93%) of the 86 newborns; 94% of these demonstrated MGA. There was a very high incidence of associated anomalies in newborns with MGA. Histologically, the blind-ending atresias showed different degrees of villous hyperplasia with or without intraluminal material. This is the first report demonstrating a high rate of occurrence of MGA in the adriamycin rat model. The injection of adriamycin early in gestation, the high incidence of associated malformations, and the anatomic and histologic findings in MGA indicate that MGA is a result of a malformative rather than an ischemic process. Accepted: 22 September 2000     

Successful Treatment of Nephrotic Syndrome Due to Collapsing Focal Segmental Glomerulosclerosis Accompanied by Acute Interstitial Nephritis

A 39-year-old woman was hospitalized for nephrotic syndrome. Laboratory test results showed increased serum creatinine levels and urinary excretions of beta-2-microglobulin, and N-acetyl-beta-D-glucosaminidase. A renal biopsy revealed collapsing focal segmental glomerulosclerosis (FSGS) and acute interstitial nephritis. Despite treatment with pulse steroid followed by oral high-dose glucocorticoids and cyclosporines, heavy proteinuria persisted. After low-density lipoprotein apheresis (LDL-A) therapy was initiated, her proteinuria gradually decreased, leading to complete remission. A repeat renal biopsy after treatment revealed no collapsing glomeruli. Immediate LDL-A should be performed to treat cases of collapsing FSGS poorly responding to other treatments.     

Comparison of intensity-modulated radiotherapy with the 5-field technique,helical tomotherapy and volumetric modulated arc therapy for localized prostate cancer

The outcomes of three methods of intensity-modulated radiation therapy (IMRT) for localized prostate cancer were evaluated. Between 2010 and 2018, 308 D’Amico intermediate- or high-risk patients were treated with 2.2 Gy daily fractions to a total dose of 74.8 Gy in combination with hormonal therapy. Overall, 165 patients were treated with 5-field IMRT using a sliding window technique, 66 were then treated with helical tomotherapy and 77 were treated with volumetric modulated arc therapy (VMAT). The median age of patients was 71 years. The median follow-up period was 75 months. Five-year overall survival (OS) and biochemical or clinical failure-free survival (FFS) rates were 95.5 and 91.6% in the 5-field IMRT group, 95.1 and 90.3% in the tomotherapy group and 93.0 and 88.6% in the VMAT group, respectively, with no significant differences among the three groups. The 5-year cumulative incidence of late grade ≥2 genitourinary and gastrointestinal toxicities were 7.3 and 6.2%, respectively, for all patients. Late grade ≥2 gastrointestinal toxicities were less frequent in patients undergoing VMAT (0%) than in patients undergoing 5-field IMRT (7.3%) and those undergoing tomotherapy (11%) (P = 0.025), and this finding appeared to be correlated with the better rectal DVH parameters in patients undergoing VMAT. Other toxicities did not differ significantly among the three groups, although bladder dose-volume parameters were slightly worse in the tomotherapy group than in the other groups. Despite differences in the IMRT delivery methods, X-ray energies and daily registration methods, all modalities may be used as IMRT for localized prostate cancer.