Changes in CSF pressures during experimental acute arterial subdural bleeding in pig

Summary The effects of acute arterial subdural bleeding on cerebrospinal fluid (CSF) pressure and 12 other vital parameters were studied in spontaneously breathing pigs (group 1, n=9) and in mechanically ventilated pigs (group 2, n=18) to analyze quantitatively the bleeding course and the lethal mechanism.Spontaneously breathing animals all succumbed after a mean bleeding volume of 45.6±8.9ml, corresponding to about 50 per cent of the intracranial volume, and a mean bleeding duration of 11.0±2.6 min. Rapid rise in CSF pressures, marked transtentorial pressure gradients, and progressive reductions of cerebral perfusion pressure leading to a permanently iso-electric EEG, apnoea and to a terminal rise in arterial pressure (Cushing response), was the rule in these animals.The mechanically ventilated animals had smaller bleeding volumes (34.3±8.1 ml), but longer bleeding durations (13.8±5.8 min). In this group 7 animals survived. They had no pressure gradients, and only moderate changes in arterial pressure and EEG. The 11 animals that succumbed had marked transtentorial pressure gradients, but smaller increments in arterial pressure than the spontaneously breathing animals.At autopsy, subdurally located blood was found throughout the intracranial and spinal subdural compartments and along the spinal nerve roots in both groups.The results of this study suggest that survival after acute subdural haematoma is influenced by the presence of transtentorial pressure gradients and by the spinal sac acting as a space for expansion. The beneficial effect of artificial ventilation is discussed.This study has been supported by the University of Oslo, The Anders Jahre Foundation for The Advance of Research, and by the Norwegian Society for fighting Cancer.     

Successful visual rehabilitation after neonatal penetrating keratoplasty

BACKGROUND—Penetrating keratoplasty in infancy and childhood has traditionally met with limited visual success due to a combination of unique physiology and technical problems in this patient population. With the advances in microsurgical instrumentation, corneal preservation, and visual developmental physiology ophthalmologists are finding increasing indications for penetrating keratoplasty in the childhood population. The long term results of neonatal penetrating keratoplasty in two patients with unilateral congenital corneal opacification are reported.
METHODS—Penetrating keratoplasty was performed on one eye in each of two infants within the first 3 weeks of life. Amblyopia treatment and optical therapy have been continued since surgery.
RESULTS—After 6 years both grafts have remained clear. One patient developed the infantile esotropia syndrome. Visual development using Snellen optotypes is age normal for both transplanted eyes.
CONCLUSIONS—Penetrating keratoplasty when combined with optical correction and amblyopia therapy may restore and preserve vision in selected patients with congenital corneal opacification if performed in the neonatal period.

     

Epithelial downgrowth following the removal of iris inclusion cysts

We present three patients in whom epithelial downgrowth occurred following the excision of iris inclusion cysts. The sheet-like downgrowth was aggressively treated and successfully eradicated in two of the three patients. Early identification and prompt therapy are essential.     

Plasminogen activator inhibitor type 2 in human corneal epithelium

PURPOSE: To examine normal human corneal epithelium in vivo and in vitro for expression and status of plasniinogcn activ:ltor inhibitor type 2 (PAI-2). METHODS: Normal hiuman corneas were prepared for frozen sections and for culture of corneal keratinocytes. PAI-2 was analyzed by immunohistochemistry and western blot analysis uising antibodies that recognize all forms of PAI-2. RESULTS: In vivo and in vitro, PAI-2 was immunohistochemically localized to the superficial corneal keratinocytes. Immunostaining also revealed the presence of PAI-2 in its relaxed (i.e., cleaved) conformation. In vivo, the staining pattern of the relaxed form was identical with that of total PAI-2, but in vitro the relaxed form was detected in a smaller subpopulation of superficial cells. In vitro, the staining pattern indicated a cytoplasmic localization for PAI-2. Western blot analysis revealed that most of the PAI-2 was cell associated and functionally active. CONCLUSIONS: The present results are the first to show that PAI-2 is found in normal human corneal epithelium in vivo and in vitro, where it can be considered as a differentiation product. At least in vitro, all detectable PAI-2 is cell associated, with a cytoplasmic distribution. A subpopulation of keratinocytes also contains PAI-2 in its relaxed (i.e., cleaved) conformation. Cleavage by an as yet unidentified cytoplasmic proteinase may constitute a crucial aspect of the function of corneal epithelial PAI-2, which may be relevant to terminal differentiation and death of the corneal keratinocyte.     

A modified single-loop reconstruction after pancreaticoduodenectomy reduces severity of postoperative pancreatic fistula in high-risk patients

Background

Double-loop (DL) reconstruction after pancreaticoduodenectomy (PD), diverting pancreatic from biliary secretions, has been reported to reduce rates and severity of postoperative pancreatic fistula (POPF) compared to single loop (SL) reconstruction at the price of prolonged operative duration. This study investigated the feasibility of a new reconstruction method combining the advantages of DL with the simplicity of SL in patients with high-risk pancreas.

Quantitative assessment and determinants of suture-holding capacity of human pancreas

Background

Hard pancreas is welcome by surgeons performing resective pancreatic surgery, because it is believed to offer better suture holding capacity (SHC), thus decreasing the risk for a postoperative leak. However, neither the actual SHC of pancreatic tissue in humans nor its determinants have been studied.

Methods

We directly measured SHC for polydioxanone 5–0 suture and tissue hardness at the pancreatic isthmus in 53 human pancreata using a dynamometer and a durometer. A histologic score based on fibrosis grade, fat content, pancreatic duct size, and signs of chronic pancreatitis was calculated for every sample. We tested the hypothesis that SHC of the pancreas was proportional to tissue hardness, and evaluated the role of different possible histomorphologic determinants of SHC.

Results

Suture-holding capacity correlated perfectly with tissue hardness (r = 0.98; P < 0.001; 95% confidence interval, 0.96–0.99). The histologic score showed a stronger correlation with both parameters than any single histologic parameter. The SHC of transductal sutures was significantly higher than that of pure transparenchymal sutures. The SHC and hardness were significantly lower in patients who developed a clinically relevant pancreatic fistula postoperatively.

Conclusions

A mixture of histomorphologic features of human pancreas determines its tissue hardness and SHC. Involvement of the main pancreatic duct in the suture line appears to increase the mechanical strength of the pancreatic anastomosis.     

18F]Fluorodeoxyglucose positron emission tomography surveillance of hepatic metastases from prostate cancer following radiofrequency ablation: a case report

The liver is the organ most commonly involved with metastatic disease. Surgical resection of hepatic metastases is the only potentially curative therapy, but it is possible in only 20 per cent of the patients. Radiofrequency ablation (RFA) of hepatic lesions is a therapeutic option for unresectable hepatic metastases. Today there is no clear consensus about which imaging technique is the most reliable to monitor RFA therapy. [18F]Fluorodeoxyglucose (FDG) positron emission tomography (PET) is a new imaging modality allowing evaluation of glucose metabolism that has become established for monitoring therapy and early detection of recurrence of various types of malignant tumors. We present a case report of a 61-year-old man treated for prostate carcinoma 3 years earlier who presented with rising serum prostate-specific antigen (PSA) levels. A CT scan demonstrated two hepatic metastases that were treated with RFA because the patient refused surgery. During 3 years of follow-up hepatic recurrence was monitored with serum PSA levels, CT of the abdomen, and FDG-PET imaging on multiple occasions. On three separate occasions FDG-PET revealed hypermetabolic foci despite no definite evidence of recurrence on CT. Furthermore FDG-PET imaging 2 months after the last RFA therapy showed two large photopenic areas without evidence of hypermetabolism consistent with successful RFA therapy. Serum PSA levels correlated better with FDG-PET than CT results. We conclude that in this patient FDG-PET imaging was more accurate than CT for monitoring recurrence of hepatic metastases from prostate carcinoma after RFA therapy. PET demonstrated hypermetabolic foci when there was recurrence and no evidence of hypermetabolism early after successful RFA therapy. In addition FDG-PET imaging helped to guide the placement of the RFA probe to the most metabolically active part of the tumor.     

Citrus pectin affects cytokine production by human peripheral blood mononuclear cells

Dietary fibers, including pectin, have been shown to exert a favorable effect on a wide spectrum of pathological conditions. Their positive influence on human health is explained by their anti-oxidative, hypocholesterolemic and anti-cancerous effects. However, little has been reported about their activity on the immune system. Therefore, the present study was undertaken to examine the effect of citrus pectin (CP) on cytokine production by human peripheral blood cells (PBMC). PBMC were incubated without or with CP at different degrees of esterification (DE) (∼30, ∼60 and ∼90% esterified pectin, assigned as DE30, DE60 and DE90, respectively) for detection of IL-1β, IL-1ra, TNFα, IL-6 and IL-10 secretion. Incubation with DE60 and DE90 induced a dose-dependent inhibition of the pro-inflammatory cytokine IL-1β secretion, whereas D30 did not affect this function. However, CP at all three esterification degrees did not alter the secretion of the additional pro-inflammatory cytokines examined, i.e. TNFα and IL-6. Conversely, CP at DE60 and DE90 caused a dose-dependent increased secretion of the anti-inflammatory cytokines IL-1ra and IL-10, whereas D30 did not affect the production of IL-1ra and decreased that of IL-10. The findings indicate that CP possesses the capacity to exert an immunomodulatory response in human PBMC which may have a favorable effect on human health.