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PubMed1990

Morphometric study of the microvasculature of the main excretory duct subepithelia of the rat parotid, submandibular and sublingual salivary glands.

This study investigated the relationship between the fine structure of the main excretory duct (MED) epithelia and the subepithelial capillaries of the major salivary glands (parotid, submandibular, and sublingual) in the rat. The MED subepithelial capillaries vary in type (fenestrated and continuous), number of fenestrae present in the available fenestrated endothelium (the attenuated area of endothelium), and number of capillaries per unit length of epithelium. In the parotid gland, continuous capillaries predominate, and the capillary density per 200 microns of epithelium (1.73 in region I and 1.03 in region II) is lower than in the other two glands, as is the number of fenestrae per 10 microns of available endothelium (1.97 in region I and 1.25 in region II). The submandibular gland has mainly fenestrated capillaries. The capillary density per 200 microns of epithelium (4.46 in region I and 5.51 in region II) is higher than in the other two glands, as is the number of fenestrae per 10 microns of available endothelium (4.82 in region I and 7.90 in region II). Similarly, in the sublingual gland, fenestrated capillaries are dominant. The density of capillaries per 200 microns of epithelium (4.15 in region I and 4.31 in region II) is intermediate between the parotid and submandibular glands, as is the number of fenestrae per 10 microns of available endothelium (2.98 in region I and 3.83 in region II).

Animals↗
PubMed1979

Ultrastructural observations on the capillaries of human thyroid tumours.

Ultrastructure of the capillaries of malignant and benign thyroid tumours has been examined. The material consisted of biopsies from six cases of thyroid papillary carcinoma, one case of follicular (foetal type) adenoma and six cases of nodular adenomatous goitre. In the group of nodular adenomatous goitre and in the follicular adenoma, the capillary wall was made up of fenestrated endothelium similar to that of capillaries of normal human thyroid. The fenestrae occupied a large area of the endothelial wall. Micro- and macropinocytotic vesicles were frequent in the endothelial cytoplasm. In the thyroid carcinomas the papillary structures always contained numerous capillaries with fenestrated endothelium. The microfollicular area and the solid tumoral areas of the papillary carcinoma showed occasional capillaries with fenestrated endothelium, but many capillaries were lined with continuous endothelium. The capillaries in all the specimens were surrounded externally by a continuous basement membrane which was frequently bilaminate or multilaminate. This study indicates that capillaries with fenestrated endothelium are characteristic of thyroid tumours which arise from follicular cells.

Adenoma↗
PubMed1999

Microvessel organization and structure in experimental brain tumors: microvessel populations with distinctive structural and functional properties.

We studied microvessel organization in five brain tumor models (ENU, MSV, RG-2, S635cl15, and D-54MG) and normal brain, including microvessel diameter (LMVD), intermicrovessel distance (IMVD), microvessel density (MVD), surface area (S(v)), and orientation. LMVD and IMVD were larger and MVD was lower in tumors than normal brain. S(v) in tumors overlapped normal brain values and orientation was random in both tumors and brain. ENU and RG-2 tumors and brain were studied by electron microscopy. Tumor microvessel wall was thicker than that of brain. ENU and normal brain microvessels were continuous and nonfenestrated. RG-2 microvessels contained fenestrations and endothelial gaps; the latter had a maximum major axis of 3.0 microm. Based on anatomic measurements, the pore area of RG-2 tumors was estimated at 7.4 x 10(-6) cm(2) g(-1) from fenestrations and 3.5 x 10(-5) cm(2) g(-1) from endothelial gaps. Increased permeability of RG-2 microvessels to macromolecules is most likely attributable to endothelial gaps. Three microvessel populations may occur in brain tumors: (1) continuous nonfenestrated, (2) continuous fenestrated, and (3) discontinuous (with or without fenestrations). The first group may be unique to brain tumors; the latter two are similar to microvessels found in systemic tumors. Since structure-function properties of brain tumor microvessels will affect drug delivery, studies of microvessel function should be incorporated into clinical trials of brain tumor therapy, especially those using macromolecules.

Animals↗
PubMed1985

Differential permeability of pineal capillaries to lanthanum ion in the rat (Rattus norvegicus), gerbil (Meriones unguiculatus) and golden hamster (Mesocricetus auratus).

Capillaries in the pineal gland of the rat (Rattus norvegicus), gerbil (Meriones unguiculatus) and golden hamster (Mesocricetus auratus) were investigated by means of electron-microscopical tracer studies using lanthanum. The tracer was administered together with the fixative solution by perfusion via the left cardiac ventricle. In the rat, endothelial junctions of fenestrated capillaries are permeable to lanthanum. In the gerbil the tracer does not leave the capillaries, which are of the non-fenestrated type throughout the organ. In the golden hamster the two portions of the pineal system have different types of capillaries. While in the superficial pineal fenestrated capillaries permeable to lanthanum predominate, the deep pineal possesses capillaries that are, without exception, devoid of fenestrations and impermeable to the tracer. It is suggested that differences in the structure of the capillaries are related to differences in the extent of a specialized contact of the pineal gland to the third ventricle.

Animals↗
PubMed1979

Three dimensional organization of mammalian adrenal cortex. A scanning electron microscopic study.

The adrenal cortex of different mammals was studied by SEM in order to demonstrate its actual three-dimensional organization. In the rat, as well as in the cat and pig, the adrenal cortex appeared as a "tunnelled continuum" of polyhedral cells arranged in plate-like structures (laminae). This laminar arrangement was more evident in the inner fasciculate and reticular zones where the cortex revealed a striking similarity to liver tissue. The polyhedral cells of all cortical zones possessed regular facets populated by small pits, larger invaginations and numerous microvilli with the exception of very short and smooth areas probably corresponding to attachment zones and/or gap junctions. This cellular architecture produced a labyrinthic system of intercellular channels or lacunae in which the capillaries were suspended. The pericapillary areas of this labyrinth contained microvilli, amorphous material, a delicate net of fibrils and occasional cells. The intercellular compartment of this lacunar system was mainly bordered by numerous microvilli arising from endocrine cells. The luminal surface of the capillary wall showed not only irregularly protruding margins (interpretable as endothelial junctions) but also clearly overlapping and flattened endothelial extensions. In all the animals and areas of the adrenal cortex examined, the endothelial wall was provided with abundant clusters of small fenestrations (about 50 nm in diameter) generally arranged in sieve plates. Larger fenestrations were noted mainly in the fasciculate and reticular zones of the cat and pig and occasionally in the rat. A final point related to the nature and significance of sinusoidal fenestrations was the occurrence of irregularly shaped and intracapillary located cells mainly noted in the deeper zones of the fasciculate and reticular zones of the gland. These elements--possessing the surface characteristics of macrophages--were observed, with their irregular and slender evaginations, in close proximity to the large fenestrations in a manner reminiscent of Kupffer cells within the lumen of liver sinusoids.

Adrenal Cortex↗
PubMed1991

The effects of chronic serum sickness on albumin distribution and glucose utilization in rat brain.

The level of cerebrospinal fluid (CSF) protein is elevated in diseases and disease models that are associated with circulating immune complexes such as serum sickness. Circulatory immune complexes are known to deposit in the basal lamina of fenestrated capillaries and may, as a result, affect both capillary bed and parenchymal function. Since the brain has both fenestrated and unfenestrated capillaries and immune complexes deposit to a varying extent in the fenestrated capillaries in chronic serum sickness, cerebral capillary permeability to protein may be altered in some brain areas and lead to the elevation of CSF proteins. In addition various other cerebrovascular and metabolic functions may also be affected by this condition. In this study either radio-iodinated serum albumin (RISA) or 2-[14C]deoxyglucose (14C-2DG) was intravenously injected into control Wistar rats and Wistar rats with chronic serum sickness; subsequently the tissue levels of radioactivity were measured by quantitative autoradiography in 4 brain areas with fenestrated capillaries and 11 brain areas with unfenestrated capillaries. The 2-min distribution of RISA, which demarcates the volume of circulating plasma in perfused microvessels and is generally proportional to local plasma flow, was the same in control and experimental rats. The passage of RISA from blood into brain over 30 min was negligible in both groups; thus cerebral capillary permeability to albumin was not detectably increased in any of these 15 brain areas by chronic serum sickness. The rate of local cerebral glucose utilization, an indicator of local metabolic and neural activity, was calculated from the 14C-2DG data and was virtually identical in control and experimental rats.(ABSTRACT TRUNCATED AT 250 WORDS)

Albumins↗
PubMed1989

Morphometric studies on the microvasculature of pre- and paravertebral sympathetic ganglia in the adult and aged rat by light and electron microscopy.

Morphometric measurements have been made by light and electron microscopy on sections of perfused sympathetic ganglia from rats of 6-24 months of age with special reference to the microvascular bed. Capillaries, postcapillary venules and small venules comprised the majority of the vessels studied but small arterioles were, in addition, included in the light microscopical part of the study. Light microscopical measurements using image analysis showed that there was a decrease in the density of the microvascular bed (number of vascular profiles/area) and in the total vascular luminal area with age in both ganglia. The ratio of neurons to microvessels remained constant in the superior cervical ganglion (SCG) but decreased with age in the coeliac-superior mesenteric ganglion (CSMG). However, the distribution of microvessels in relation to individual neurons remained unchanged throughout life in both ganglia. Ultrastructural studies revealed fenestrations in 12% of SCG microvessel profiles and in 38% of CSMG microvessels at 6 months, but the percentage of fenestrated profiles in the CSMG had declined by 24 months. There were no significant differences in the number of fenestrations per fenestrated profile. The basal lamina surrounding the microvessels increased significantly (almost doubling) in thickness with age. The range and distribution of microvessel wall thicknesses, expressed as harmonic mean wall thickness, were comparable in both ganglia at both ages and increased linearly according to the amount of pericyte covering present. No consistently significant relationships could be discerned between the microvessel wall thickness and luminal diameter or between the wall thickness and the area available to a given volume of blood for exchange of metabolites (luminal perimeter/luminal area). We conclude that the ganglionic capillary bed is similar in both ganglia and, in old age, accommodates structural changes that occur in the ganglion by maintaining its structure and relationship to individual neurons.

Age Factors↗
PubMed1996

Ultrastructural study on the interaction of native and cationized albumin-gold complexes with mouse brain microvascular endothelium.

The main objective of this ultrastructural study was to gain insights into the cellular mechanisms responsible for the enhanced brain uptake of blood-borne cationized albumin observed by several authors utilizing quantitative methodology. Mice were injected intravenously or into the common carotid artery (in vivo experiments) or perfused in situ with solutions of native or cationized bovine serum albumin complexed with colloidal gold (BSA-G or cBSA-G respectively). The results indicate that: (1) the main drawbacks of in vivo experiments are very intense phagocytosis of the tracer particles by Kupffer cells located in the liver sinusoids and also escape of the tracer through capillaries of skeletal and heart muscles. This results in a rapid decline of the concentration and disappearance of the circulating tracer particles; (2) BSA-G and cBSA-G both in vivo (up to 30 min circulation) or after perfusion in situ (up to 15 min) do not cross the wall of brain microvessels representing the blood-brain barrier; (3) enhanced entrance of cationized albumin into the brain occurs through fenestrated endothelium of the capillaries located in the examined circumventricular organs (median eminence and neurohypophysis). Although BSA-G is also transported by these fenestrated capillaries, this process is evidently less intense than in the case of cBSA-G; (4) the enhanced passage of cBSA-G across fenestrated capillaries occurs mainly via vesicular transport (adsorptive transcytosis), through transendothelial channels and eventually through interendothelial junctional clefts; (5) the fenestrated capillaries of the choroid plexus appear to be less permeable for both tracers than those located in the other circumventricular organs.

Animals↗
PubMed1997

Nonparasitic cysts of the liver: results and options of surgical treatment.

Nonparasitic cysts of the liver (NPHC) are highly variable in respect to appearance and therapeutic approach. The treatment of these cysts varies according to the nature and appearance of the disease. Based on the variable nature of disease and the various therapeutic options, all of which were attempted in our patients, the most suitable mode of treatment for different forms of NPHC are discussed. Ninety-one patients with NPHC who had been treated surgically from 1977 through 1995 were examined retrospectively. Asymptomatic peripheral cysts measuring up to 10 cm do not require further treatment. Computed tomography (CT)-guided aspiration (n = 9) should be regarded as a palliative measure. Within a short period, CT-guided aspiration led to recurrence of symptoms in seven of our patients. Standard treatment of NPHC is fenestration with widest possible excision of the cystic wall, which can be performed laparoscopically (n = 10) or by the conventional surgical mode (n = 54). One patient was initially operated by the laparoscopic technique but developed bleeding, which necessitated conversion to the open mode. Three patients underwent synchronous laparoscopic cholecystectomy. Recurrence rates were similar: 11% in the laparoscopically treated group and 13% in the group that underwent conventional open surgery. Conventional surgical treatment was always successful in cases of solitary cysts. However, in cases of multiple cysts measuring more than 5 cm, conventional surgery was followed by recurrence of symptoms in 26% of patients (7/27), who then had to undergo a second operation. Partial resection of the liver (n = 9) was successfully performed in cases of polycystic disease (n = 5) with concomitant enlargement of the organ as well as in cases of large solitary cysts of the left lobe of the liver (n = 4). In patients in whom we found that the cysts communicated with the ductal system (n = 3), we performed a cystojejunostomy to drain the bile. The complication rate was low. In addition to frequent postoperative ascites, which necessitated no further intervention, we observed infectious complications in four patients. Twenty patients (22%) expired during a mean follow-up period of 6.2 years. Interestingly, deaths were frequently associated with malignancy (11/20). After fenestration of multiple cysts measuring > 5 cm, the patients are at high risk for recurrence. Hence partial resection of the liver is an excellent therapeutic alternative in selected patients with polycystic disease and massive enlargement of the organ in whom the disease could not be controlled by simple fenestration. The results of this study show that laparoscopic fenestration should replace the conventional surgical technique as the gold standard in cases of NPHC because the laparoscopic technique is less stressful for the patient and is associated with a rate of success similar to that of the conventional technique.

Adult↗
PubMed1992

Long-term experience with descending aortic dissection: the complication-specific approach.

We analyzed long-term results in 71 patients (45 men and 26 women) treated over 17 years for documented descending aortic dissection. Forty-nine patients were treated medically and 22, surgically. Actuarial survival was 65% at 1 year, 57% at 3 years, 50% at 5 years, and 28% at 10 years for the whole group. For the group treated medically, survival was 73%, 63%, 58%, and 25% at 1 year, 3 years, 5 years, and 10 years, respectively, and for the group treated surgically, 47%, 40%, and 28% at 1 year, 3 years, and 5 years, respectively. Ten (20.4%) of the 49 medically treated patients died early (5 of rupture), and 14 (28.6%) died late (8 of dissection). Five medically treated patients crossed over to surgical management for complications of dissection. Among the surgically treated patients, 6 underwent standard graft replacement of the proximal descending aorta, 8 underwent the fenestration procedure (with a standardized retroperitoneal abdominal approach), and 4 underwent the thromboexclusion operation. Specific analysis of fenestration in 14 patients (including some with persistent descending aortic dissection after replacement of the ascending aorta for dissection) found it to be safe and effective. Actuarial survival after fenestration was 77%, 77%, and 53% at 1 year, 3 years, and 5 years, respectively. Thromboexclusion was found effective, and postoperative studies confirmed thrombosis of the descending aorta with preservation of the lowest intercostal arteries. Fifteen of the 21 surviving medically treated patients agreed to return for follow-up imaging. Nine had thrombosis of the false lumen. An interesting radiographic finding was that 4 of the 15 restudied patients had a saccular aneurysm in the aorta at the level of the left subclavian artery. We recommend a complication-specific approach to the management of descending aortic dissection. Uncomplicated dissection is treated medically, whereas complicated dissection is treated surgically, with realized rupture treated by standard graft replacement, limb ischemia treated by fenestration, and enlargement or impending rupture treated by thromboexclusion.

Adult↗
PubMed2006

Hyperlipidemia and surfactants: the liver sieve is a link.

Poloxamer 407 is a ubiquitous synthetic surfactant that causes massive hyperlipidemia and atherosclerosis in the rodent. The initial step in hepatic metabolism of lipoproteins is their transfer through 100-200 nm pores (fenestrations) in the liver sinusoidal endothelial cell, prior to receptor-mediated uptake. The 'liver sieve hypothesis' emphasizes the role of these fenestrations in the regulation of lipoprotein disposition. Here we show that P407 causes dramatic defenestration of the liver sinusoidal endothelium in vivo. By 24h after intraperitoneal administration in mice, fenestrations were reduced by approximately 80% coincident with a 10-fold increase in plasma lipids. Moreover impulse-response experiments in the perfused rat liver showed that P407 prevented the passage of small chylomicrons across the liver sinusoidal endothelium. Defenestration was also induced acutely with P407 in isolated liver sinusoidal endothelial cells, indicating this is a direct effect of P407 on fenestrations. The results establish the role of the porosity of the liver sinusoidal endothelial cell as a pivotal yet relatively unrecognised mechanism for hyperlipidemia. Furthermore, the results establish an intriguing mechanism for surfactant-induced hyperlipidemia. Thus the liver sieve is a new and untapped target for the treatment and prevention of hyperlipidemia.

Animals↗
PubMed2006

Marked changes of the hepatic sinusoid in a transgenic mouse model of acute immune-mediated hepatitis.

BACKGROUND/AIMS: The liver sinusoidal endothelial cell (LSEC) is increasingly recognized as having an important role in hepatic immunity. However, the responses of LSECs and the hepatic sinusoid in immune-mediated hepatitis are poorly described. METHODS: We studied a transgenic mouse model of acute immune-mediated hepatitis: Met-Kb mice injected with T cells from Des-TCR mice. RESULTS: Hepatitis was characterized by lymphocyte infiltrates causing severe but transient liver damage. There were marked changes in the ultrastructure of the LSEC five days after injection of the T cells that coincided with the peak of the hepatitis. The porosity of fenestrations in the LSEC decreased and the endothelium became thickened. LSECs appeared to be markedly activated. These changes were associated with narrowing of the space of Disse, loss of hepatocellular microvilli and deposition of basal lamina. Lymphocytes were seen passing through fenestrations. Loss of fenestration in the LSEC prevented hepatitis induced by a second injection of lymphocytes on day 5. CONCLUSIONS: Structural changes in the LSEC occur during the peak of a mouse model of immune-mediated hepatitis. These changes were associated with attenuation of subsequent liver damage, suggesting that they may influence immunological responses mediated by LSECs or the passage of lymphocytes through LSEC fenestrations.

Acute Disease↗
PubMed1998

Host microvasculature influence on tumor vascular morphology and endothelial gene expression.

We have previously demonstrated that vascular endothelial growth factor-165 (VEGF), a tumor-secreted angiogenic factor, can acutely and chronically induce fenestrations in microvascular endothelium (Cancer Res 1997, 57:765-772). Because the morphology and function of microvascular endothelium differs from tissue to tissue, we undertook studies to examine whether the neovasculature in tumors also differed depending upon tumor location. Four tumor types implanted in the brain or subcutis in nude mice were studied: a murine rhabdomyosarcoma (M1S), a murine mammary carcinoma (EMT), and two human glioblastomas (U87 and U251). In addition, we studied Chinese hamster ovary cells stably transfected with human VEGF165. As previously reported, tumors grown in the subcutaneous space had a microvasculature that was fenestrated and had open endothelial gaps. The identical tumors when grown in the brain also had fenestrated endothelium and vessels with open endothelial gaps, but they were drastically reduced in occurrence. Open endothelial gaps were not seen in all tumors implanted in the brain (EMT and M1S), although fenestrated endothelium was always seen. VEGF and VEGF receptors were measured in tumors from both locations by immunoblotting and competitive polymerase chain reaction, respectively. VEGF amount was not significantly different between the tumor locations. Interestingly, total tumor vascular mRNA expression of both Flk-1 and Flt-1 was greater in tumor vessels derived from the brain compared with tumor vessels derived from subcutaneous tissues. These results demonstrate that the host microvascular environment determines the morphology and function of the tumor vasculature and that endothelia from different tissues vary in their ability to express the VEGF receptors given identical stimuli.

Animals↗
PubMed2002

Fontan-type procedures: residual lesions and late interventions.

BACKGROUND: The purpose of this study was to determine the type and incidence of hemodynamic and electrophysiological abnormalities requiring surgical or catheter-based interventions in a single-center long-term experience. METHODS: Eighty-eight patients with a follow-up of at least 5 years (mean follow-up, 9.6 +/- 2.6 years) after Fontan-type procedures were included. All patients had undergone cardiac catheterization either as part of the regular postoperative protocol or because of symptomatic atrial tachycardia or increasing cyanosis. RESULTS: Freedom from reoperation for up to 5 years was documented for 82% of patients and decreased to 76% after 8 years. Late reoperations included conversion of an atriopulmonary anastomosis to a total cavopulmonary anastomosis in 2 patients with atrial dysrhythmia and implantation of an extracardiac conduit in 1 patient with left atrial isomerism and intrapulmonary arteriovenous malformations after a Kawashima operation. Decline in sinus node function with symptomatic bradycardia required pacemaker therapy in 10 patients (11%). Transcatheter interventions included fenestration occlusion in 5 of the 11 patients with initial baffle fenestration. In 6 of 17 patients with aortopulmonary collaterals, coil occlusion was indicated to reduce future systemic ventricular volume load. Various systemic venous collaterals were documented in 11 patients and required coil occlusion in 2. One patient with symptomatic protein-losing enteropathy underwent transcatheter fenestration creation without sustained relief of symptoms. Freedom from transcatheter interventions decreased from 94% to 82% after 5 and 10 years, respectively. CONCLUSIONS: During long-term follow-up, reoperations are rare and mainly involve Fontan conversion to either a lateral-tunnel or extracardiac-conduit procedure. Detailed angiographic evaluation on a routine basis allows identification of the vascular sites of origin of aortopulmonary collateral vessels and systemic venous collaterals potentially developing during long-term follow-up. Transcatheter interventions including fenestration occlusion and occlusion of venous collaterals and aortopulmonary collaterals were performed to maintain and improve the Fontan circulation in clinically symptomatic and asymptomatic patients. During long-term follow-up after Fontan-type operations, a regular postoperative cardiac catheterization protocol is recommended.

Adolescent↗
PubMed1995

Surgery for adult polycystic liver disease.

BACKGROUND: Occasionally patients with adult polycystic liver disease (APLD) have symptoms. For these patients surgery may represent a valuable therapeutic option to relieve symptoms. METHODS: From September 1977 to August 1993 at our institution, 10 women with APLD were examined and surgically treated. They underwent a partial hepatic resection together with cyst fenestration. The surgical outcome and long-term follow-up were retrospectively analyzed. RESULTS: Postoperative morbidity consisted of one case of pneumonia, and one case of acute pancreatitis with deep vein leg thrombosis. One patient died after acute Budd-Chiari syndrome developed as a result of liver collapse after fenestration of a posterior cyst. In the long term six of nine patients were symptom free. Late surgical complications included acute cholecystitis (one patient), small bowel obstruction (one), and incisional hernia (two). CONCLUSIONS: A combined surgical approach of hepatic resection and cyst fenestration has proved feasible for patients with highly symptomatic APLD. Extensive fenestration of posterior cysts should be avoided; transverse hepatic resection (frontal hepatectomy) up to the costal margin is proposed. This therapy provides good results at long-term follow-up.

Adult↗
PubMed2000

Permeable endothelium and the interstitial space of brain.

1. Fenestrated vessels can be reversibly induced in brain by agents that stimulate urokinase production. This plasminogen activator, like vascular endothelial growth factor and metalloproteinases, is secreted by tumor cells and may account for induction of fenestrated vessels. Why only some of the brain's barrier vessels are converted to fenestrated vessels is unknown. 2. The structures responsible for the filtering of solutes by fenestrated vessels may be the same as those of continuous, less permeable vessels: the glycocalyx on the surfaces of the endothelial cells and the subendothelial basal lamina. 3. Solutes leaving the cerebral ventricles immediately enter the interstitial clefts between the cells lining the ventricles. A fraction of a variety of solutes, injected into CSF compartments, is retained by subendothelial basal lamina, from which the solutes may be released in a regulated way. 4. The brain's CSF and interstitial clefts are the conduits for nonsynaptic volume transmission of diffusible signals, e.g., ions, neurotransmitters, and hormones. This type of transmission could be abetted by a parallel, cell-to-cell volume transmission mediated by gap junctions between astrocytes bordering CSF compartments and parenchymal astrocytes. 5. The width and contents of the interstitial clefts in fetal brain permit cell migration and outgrowth of neurites. The contents of the narrower and different interstitial clefts of mature brain permit solute convection but must be enzymatically degraded in order for cells to migrate through it.

Animals↗
PubMed2003

Endoscopic ventriculo-cystomy for non-communicating hydrocephalus secondary to quadrigeminal cistern arachnoid cyst.

INTRODUCTION: Intracranial arachnoid cysts are developmental, anomalous collections of cerebrospinal fluid (CSF), and occasionally cause symptoms when large enough to obliterate the CSF outflow pathway and give rise to non-communicating hydrocephalus. The treatment of choice for symptomatic arachnoid cysts has been surgical excision or fenestration of the cyst, but less invasive endoscopic fenestration has been attempted with favorable preliminary results. CASE REPORT: We report a case of non-communicating hydrocephalus caused by a quadrigeminal cistern arachnoid cyst in a 35-year-old woman who presented with worsening headaches. She was successfully treated by endoscopic third ventriculostomy and fenestration of the cyst (ventriculo-cistomy). DISCUSSION: Endoscopic fenestration of symptomatic arachnoid cysts can be as effective as open surgery in terms of short-term efficacy, and it is certainly less invasive than open surgery. However, its long-term outcome remains unknown, and these rare cases require careful clinical and radiological follow-up.

Adult↗
PubMed2001

Univentricular repair in children under 2 years of age: early and midterm results.

BACKGROUND: Encouraging results have been obtained from early univentricular repair. Our study was designed to assess the impact of young age (less than 2 years) on the outcome of univentricular repair. PATIENTS AND METHODS: Between January 1992 and December 1998, 65 out of 311 patients undergoing univentricular repair at the All India Institute of Medical Sciences, New Delhi, were less than 2 years of age. We compared these 65 carefully selected patients (group 1) with the 246 patients who were more than 2 years of age (group 2). Since 1994, all patients of both groups had a fenestration of the intra-atrial baffle. RESULTS: The early mortality rate was 9.2% in group 1 and 7.7% in group 2. The overall Fontan failure rate was 12.3% in group 1 and 12.2% in group 2. In group 1, a higher incidence of Fontan failure was noted in patients with suboptimal weight, non-tricuspid atresia morphology, nonfenestrated Fontan and those who did not comply with more than two of Choussat's criteria, but the values were not statistically significant. Aortic cross-clamp time of more than 60 min was the only and highly significant predictor of Fontan failure (P < 0.01). The overall effusion rate was 24.05% in group 1 and 27.98% in group 2. In group 1, patients weighing less than 10 kg (P = 0.0007), without fenestration of the atrial baffle (P < 0.05) and with systemic ventricular dysfunction (P < 0.001), systemic ventricular end-diastolic pressure of more than 12 mmHg (P < 0.001), mean pulmonary artery pressure of more than 15 mmHg (P < 0.001) and aortic crossclamp time of more than 60 min (P < 0.01), were all found to be significant risk factors of pleural effusion. Pulmonary artery distortion needing reconstruction did not increase the Fontan failure or effusion rates. Oxygen saturation ranged from 85 to 94% (mean 89%) in patients having a functioning fenestration at a mean follow-up period of 30 months. The actuarial survival at 84 months was 90 +/- 0.04% in group 1 and 88 +/- 0.02% in group 2. CONCLUSIONS: Our results suggest that carefully selected patients under 2 years of age are suitable candidates for one-stage univentricular repair and that survival is not significantly different from that of older patients. Routine fenestration of the intra-atrial baffle is an option available to ameliorate morbidity and obviate mortality. Non-compliance with more than two of Choussat's criteria appears to be additive in unsatisfactory outcome.

Journal Article↗