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PubMed1999

Complete endoscopic removal of colloid cysts: issues of safety and efficacy.

The ideal management of colloid cysts is controversial. Treatment options include shunting procedures, stereotactic cyst aspiration, open craniotomy for microsurgical removal, and endoscopic removal. Although recent literature would suggest endoscopic removal is a reasonable approach, issues of safety and efficacy have dampened the universal acceptance of this surgical modality. The author performed a retrospective anaylsis to address these controversial issues. The charts of all patients in whom endoscopic removal of colloid cysts was performed by the primary author at the University of Arkansas for Medical Sciences were reviewed. Eighteen patients underwent this procedure over the last 5 years. The mean patient age was 32 years, and the mean follow-up period was 32 months. In all patients complete tumor removal was macroscopically and radiologically confirmed, and there were no permanent deficits. Two patients suffered aseptic meningitis without long-term sequelae. There were no deaths and no incidence of tumor recurrence. The results of this series support those previously published that underscore the advantages of endoscopic removal of colloid cysts. The procedure is safe and effective. Longer follow-up review is required to address the issue of duration of tumor-free survival.

Journal Article↗
PubMed1986

Neuroepithelial (colloid) cyst of the third ventricle in identical twins. Case report.

Colloid cysts of the third ventricle are described in middle-aged twin brothers. One of them presented with recurrent attacks of headache. In this patient the cyst had reached a size large enough to obstruct the cerebrospinal fluid pathway, resulting in hydrocephalus. The twin brother, although asymptomatic, was suspected of the anomaly and investigated because of the similarity of his ocular signs. The diagnosis was confirmed by computerized tomography in both the patient and his brother. The latter proved to have a smaller colloid cyst situated anteriorly in the third ventricle with no obstructive hydrocephalus. The patient was successfully operated on, while the brother is still under observation. Both brothers have had bilateral cataracts, retinal detachments, and left lateral rectus palsies. The familial occurrence of colloid cysts and their association with these ocular findings have apparently not been described before.

Adult↗
PubMed1989

Treatment of colloid cysts of the third ventricle by stereotaxic microsurgical laser craniotomy.

The therapeutic strategies employed in the management of anterior third-ventricular mass lesions remain controversial. Resection by conventional craniotomy, whether via a transcallosal or transcortical approach, carries well-known risks and limitations. Alternatively, in this region traditional stereotaxy has been relegated to use with biopsy only or cyst aspiration procedures. Combining aspects of both conventional and stereotaxic techniques has allowed total removal of 12 colloid cysts in six women and six men ranging in age from 25 to 71 years. No mortality and minimal morbidity have been associated with the procedures. There has been no evidence of recurrence in an average follow-up period of 19 months. By coupling the benefits of stereotaxic precision and localization to the microsurgical management of colloid cysts, several rewards have been realized: 1) only a limited cortical dissection is needed; 2) the hazards of callosal or forniceal injury can be avoided; 3) the lesion is easily localized regardless of ventricular size; 4) hemostasis can be readily achieved with bipolar cautery or defocused laser power; and 5) most importantly, a total resection is possible with little risk to the patient. Stereotaxic microsurgical laser craniotomy provides a new option for the management of colloid cysts and other anterior third-ventricular lesions.

Adult↗
PubMed1988

[An evaluation of predicting postoperative residual liver function using 99mTc tin colloid].

The rate of clearance (K value) of 99mTc tin colloid in the liver differentiates normal subjects from liver cirrhosis patients; so 99mTc tin colloid is as useful as 198Au colloid as a marker of liver function. There are several reports concerning volume estimation using liver scintigraphy. Our original method was devised to measure the effective liver volume by scintigraphy. By combining the K value with effective liver volume, a predictive index was obtained in order to predict the residual liver function before hepatic resection. The index in 24 patients with liver diseases was investigated before hepatic resection. Three of them died due to hepatic failure after hepatic resection. The indices were between 0.40 and 0.45 in two of these three patients and 0.338 in one. Among the patients without hepatic failure, the indices showed more than 0.45 in 19 patients and between 0.40 and 0.45 in two. These results indicate that the limitation of hepatic resection is between 0.40 and 0.45 of the predictive index.

Adult↗
PubMed2001

Significance of lymphoscintigraphic mapping with Tc-99m human serum albumin and tin colloid in sentinel lymph node biopsy in breast cancer.

Sentinel lymph node biopsy (SLNB) in breast cancer is considered in order to spare node-negative patients from axillary lymph node dissection. To assess the clinical significance of lymphoscintigraphic mapping in SLNB, we analyzed the lymphatic drain to the sentinel lymph nodes (SLNs) in terms of the pattern and direction of the hot spot. Twenty-three breast cancer patients were enrolled for SLNB. Before surgery, lymphoscintigraphic mapping of SLN was performed using Tc-99m human serum albumin (HSA) and tin colloids, and the hot spot was marked. The Tc-99m HSA and tin colloids were subcutaneously injected above the tumor and peritumor sites, respectively, and lymphoscintigraphic scanning was monitored every 5 to 10 min, for up to 2 h after injection. The SLN was identified using a combination of a blue dye, indigocalmine, and a gamma probe during surgery. The hot spot pattern and direction of the lymphatic drains were evaluated in 21 of 23 cases. Two cases did not have a hot spot. Single, double, and multiple hot spots were observed in 12 cases (52.1%), 8 cases (34.7%), and 1 case (4.3%), respectively. The positions of the hot spots were: axillary (n=17, 80.9%), axillary and sternal (n=3, 14.2%), and phrenic (n=1, 4.7%). The sensitivity and specificity rates in SLNB were 66.6% and 100%, respectively, and the overall predictive rate was 85.7%. Lymphoscintigraphy produced false negatives in three cases (33.3%), including one on the phrenic side. Lymphoscintigraphic mapping with Tc-99m HSA and tin colloids is useful for determining the SLN, and avoiding a false negative. The pattern and direction of the lymphatic drain to the SLN in scintigraphy need to be considered for the elimination of axillary lymph node dissection in node-negative patients with breast cancer.

Adult↗
PubMed2000

[Comparative effects of autologous blood transfusion and isovolemic colloids transfusion on hemorrhagic shock: measurement of NO production and tissue oxygen pressure].

Effects of autologous blood transfusion and isovolemic colloids transfusion on hemorrhagic shock model in rats were investigated. The hemorrhagic shock model in rats was prepared by rapid exsanguination and the blood pressure was kept at 40 mmHg for 30 min. As a marker of hemodynamic change, the blood gas analysis was performed, and the tissue oxygen pressure of the liver and the spleen was also measured. Furthermore, we analyzed the changes in NO production in the liver and the spleen of the hemorrhagic shock model. By hemorrhagic shock, Ht, HCO3-, base excess, and PaO2 levels decreased, and liver NO level, but not spleen NO, increased rapidly. However, the liver PtO2 did not show any changes during hemorrhagic shock, although the spleen PtO2 tended to decrease. These changes seen at the hemorrhagic shock were equally restored after the treatment with either autologous blood transfusion or isovolemic colloids transfusion. These results indicate that either autologous blood transfusion or isovolemic colloids transfusion can be useful for the therapy of severe hemorrhagic shock, and the NO production in the liver can participate in the maintenance of homeostasis under hemorrhagic shock.

Animals↗
PubMedDate not supplied

Colloid cyst of the third ventricle: a cause of sudden death in a child.

Colloid cyst is a rare benign intracranial neoplasm, commonly located in the third ventricle. Though headache and visual symptoms are classical, the patients may present with sudden neurological deterioration. We present a ten-year-old male child who presented with sudden neurological deterioration due to colloid cyst of the third ventricle resulting in death. The child had intermittent headache for three months, for which medical attention was not sought. This report details the case and a short review of the condition is presented (with emphasis on the clinical features and importance of early diagnosis). Management (including surgical methods and conservative treatment) of third ventricle colloid cysts is briefly reviewed.

Adult↗
PubMed2005

[Transitory headaches caused by a colloid cyst of the third ventricle].

A 34-year-old man had a history of short-lasting episodes of rotatory vertigo followed by severe headache, provoked by sudden movements of the head and body. MRI of the brain revealed hydrocephalus secondary to a colloid cyst at the level of the foramen of Monro. The patient underwent microsurgery, after which he remained without symptoms. Colloid cysts are rare, benign tumours accounting for 0.5-1.0% of all primary brain tumours. They are attached by a stalklike appendage to the roof of the third ventricle between the fornices. Typical symptoms include intermittent headache, vomiting, occasional dizziness and blurred vision. These symptoms may be secondary to intermittent obstruction of cerebrospinal-fluid outflow through the foramen of Monro. The results of clinical and neurological examination are usually normal. In any patient with short-lasting episodes of severe headache, provoked by changes in position, an MRI of the brain should be done to exclude a colloid cyst. In general, these patients do not fulfil the criteria of the International Headache Society for migraine because of the short-lasting nature of the pain.

Adult↗
PubMed1999

[Surface-enhanced Raman spectroscopy of riboflavin in silver colloids using 1 064 nm excitation].

Surface-enhanced Raman spectra (SERS) of riboflavin in silver colloids, using near-infrared (NIR) laser operating at 1 064 nm wavelength, were obtained. The enhancement factor was further increased by improving the preparation of silver colloid and with the addition of a small amount of NaOH. The detection limit was lower than 3.2 x 10(-10) mol x L(-1). It is concluded that the larger and aggregated silver particles were more efficient for the electromagnetic enhancement of NIR-SERS. Flavin ring was absorbed on the colloidal silver methal surface, standing on oxygens of C(20)=O) and C(4)=O.

English Abstract↗
PubMed2004

Synthesis and crystallization of hybrid spherical colloids composed of polystyrene cores and silica shells.

The Stöber method has been adopted to prepare hybrid core-shell particles by coating the surfaces of monodisperse polystyrene beads with uniform silica shells. Polystyrene beads with diameters in the range of 0.1-1.0 microm have been successfully demonstrated for use with this process, and the thickness of the silica coating could be controlled in the range of 50-150 nm by adjusting the concentration of tetraethoxysilane, the deposition time, or both. The morphology and surface smoothness of the deposited silica were found to strongly depend on a number of parameters such as the surface functional groups on the polymer beads, the pH value of the medium, and the deposition time. Hollow spheres made of silica could be obtained by selectively removing the polymer cores via calcination in air at an elevated temperature or by wet etching with toluene. These core-shell colloids were also explored as building blocks to fabricate long-range ordered lattices (or colloidal crystals) that exhibited stop bands different from those assembled from spherical colloids purely made of either polystyrene or silica.

Journal Article↗
PubMed2005

Does preloading with colloids prevent hemodynamic changes when neurosurgical patients are subsequently changed to the seated position?

OBJECTIVE: This prospective, randomized, double-blind study was designed to determine and compare the usefulness of preloading colloids (Haemaccel) 10 ml/Kg before positioning whether it can prevent hemodynamic changes during seated positioning or not. MATERIAL AND METHOD: The authors studied 20 patients by randomly dividing them into 2 groups. The control group was given crystalloid as maintenance and deposit replacement but the study group was given extra colloids 10 ml/Kg 30 minutes before starting general anesthesia. Both groups were monitored and given anesthesia, balanced technique. Systolic and diastolic blood pressures, heart rate, central venous pressure (CVP) at different time intervals in the sitting position for 30 minutes were recorded. Statistical analysis was done by Student t-test, Chi-square test and ANOVA (p-value < 0. 05 considered significant). RESULTS: The results showed that systolic blood pressure at 15, 20, 30 minutes and CVP at 15, 25, 30 minutes after positioning in the study group was maintained significantly compared to the control group and there were no significant changes in diastolic blood pressure and heart rate. There were no other complications during the sitting period. CONCLUSION: It is concluded that preloading colloid fluid prior to repositioning could prevent the decrease of systolic blood pressure and central venous pressure during sitting positioning without other complications.

Adult↗
PubMed1991

[Intra-arterial and intraportal infusion liver scintigraphy using 99mTc-labeled colloid].

Intra-arterial infusion liver scintigraphy was performed in 11 patients with primary or metastatic liver tumor, and intraportal infusion liver scintigraphy was performed in 6 patients for prophylaxis of liver metastasis from colorectal cancer. 99mTc-Sn colloid or 99mTc-phytate was administered through the catheter of which tip was placed in the portal vein or the hepatic artery, and then liver image was obtained. When 99mTc-phytate was infused intra-arterially, significant amount of the infused tracer passed through the liver and we could not get sufficient information to assess the distribution of drug administered through the catheter. On the other hand, intraportal infusion liver scintigraphy using 99mTc-Sn colloid or 99mTc-phytate and intra-arterial infusion liver scintigraphy using 99mTc-Sn colloid revealed heterogeneity of liver uptake, tracer uptake in spleen, low uptake area corresponding to the liver tumor and high uptake area around it. The findings will be clinically useful, and these methods are thought to be helpful to confirm the satisfactory drug distribution.

Adult↗
PubMedDate not supplied

Adjuvant internal hepatic radiotherapy using colloidal 32P chromic phosphate in colorectal cancer.

The purpose of the study is to investigate the value of adjuvant radiotherapy given in the form of colloidal chromic phosphate 32P suspension administered via portal vein, in preventing the growth of occult metastases in the liver. Twenty two patients (10 patients of treated group with 12 controls) were followed 12 months after operation. There was no significant change in the CBC and liver functions after administration of 32P labeled colloidal chromic phosphate. Although local recurrence rates were very similar in both groups of colorectal cancer (3/12 in the control group and 4/10 in the treated group), liver metastasis rates were quite different: 4/12 in the control group and none (0/10) in the treated group. In conclusion, 32P labeled colloidal chromic phosphate is expected to prevent liver metastases of completely resected colorectal cancer.

Chromium↗
PubMed1979

Evaluation of bone-marrow scanning with technetium-99m sulfur colloid in pediatric oncology.

Eighty-six technetium-99m sulfur colloid (Tc-SC) bone-marrow scans in 56 pediatric oncology patients were reviewed. The distribution of the sulfur colloid was similar to that in adult bone marrow in normal children older than 10 yr, and involved progressively more marrow of the extremities in normal children under 10 years of age. After irradiation or chemotherapy there was an extension of the Tc-SC to peripheral marrow sites. There was also diminished uptake of the tracer in sites corresponding to irradiated areas. In most patients there was recovery of these defects by 6 mo after completion of therapy. Tumor replacement of the marrow was reflected in the scans, and the extent of the scan defect paralleled the course of the disease. In four patients, despite normal bone scans and radiographs, marrow-scan abnormalities due to tumor replacement were present and confirmed by needle aspiration and/or biopsy. In two other patients, the marrow-scan abnormality preceded radiographic and histologic evidence of tumor metastasis. Two patients who responded clinically showed persistent defects; biopsy in one revealed fibrosis. Technetium-99m sulfur colloid bone-marrow scanning appears to be a sensitive monitor of marrow alteration caused by metastases, irradiation damage, or tissue fibrosis in children receiving treatment for cancer.

Adolescent↗
PubMed1985

Nodular colloid degeneration: distinctive histochemical and ultrastructural features.

We recently evaluated a patient with a unique form of nodular colloid degeneration. Lesions consisted of pruritic, purpuric plaques involving the upper and lower extremities and the neck. Examination of a biopsy specimen revealed large, fissured masses of amorphous material in addition to solar elastosis. The amorphous material showed negative reactions to stains for amyloid, and other histochemical studies showed results similar to those for colloid milium. The amorphous masses demonstrated a marked positive reaction to the Verhoeff-van Gieson stain for elastin. Electron microscopic examination revealed masses of degenerated elastic tissue bordered by fibrillar material that resembled amyloid morphologically. We believe this case represents a nodular form of solar degeneration with clinical and histologic resemblances to both colloid milium and cutaneous amyloidosis.

Amyloidosis↗
PubMed1987

[Origin of colloid cyst: immunoperoxidase study].

Despite their consistent anatomic location and histological features, the histogenesis of colloid cysts has remained obscure. We report immunohistochemical data on surgically excised cysts in attempt to define the origin of the lining epithelial cells. Paraffin-embedded tissues from colloidal cysts (7 in the 3rd ventricle and one in the sella) and two similar epithelial cysts (one in the cerebellopontine angle and one in the sella) were investigated. After examination by conventional stains, immunoperoxidase studies were carried out using primary antisera against epithelial membrane antigen (EMA), tissue polypeptide antigen (TPA), epidermal keratin (EK) and S-100 protein. The apical plasma membrane, surface microstructures were consistently EMA positive. Columnar cells demonstrated cytoplasmic staining for TPA. Basal cells of lining epithelia expressed EK. All epithelia studied were negative for S-100 protein. These findings suggest an endodermal origin of colloid cysts.

Adult↗
PubMed1989

A colloidal gold labeling technique for the direct determination of the surface area of eukaryotic cells.

We have developed a colloidal gold labeling technique for the direct quantitation of the cell surface area. The method is based on coating the cell surface with [195Au] colloidal gold-protein complexes followed by morphometric determination of the labeling density (gold particles/micron2 cell surface) and radiometric determination of the total number of gold particles bound per cell. The ratio of both values directly gives the cell surface area. The accuracy of the method was shown using Staphylococcus aureus cells as a model system, where the cell surface area determined with our assay (4.0 microns2) corresponded well to the value calculated from the radius of the cells (3.6 microns2). In a more complex model system J-774 mouse macrophages were labeled with different amounts of [195Au] gold-protein complexes to show that the assay is independent of the degree of saturation of the cell surface binding sites. Both high (135 Au/microns2) and low (65 Au/microns2) labeling densities resulted in a surface area of about 1200 microns2. The technique finally was applied to L-929 fibroblasts to determine the increase of the cell surface area when the cells change from a spherical to a flat monolayer state. We found that the cell surface area increased 3-fold during the spreading process. The results show that the colloidal gold labeling technique allows the direct determination of the surface area of complex eukaryotic cells. The technique is suitable for the quantitation of changes in the surface architecture known to occur in different functional states of eukaryotic cells.

Animals↗
PubMed1989

[The alterations of serum colloid osmotic pressure, serum protein and water balance during prolonged anesthesia].

The changes of serum colloid osmotic pressure (COPm), serum protein and water balance were examined in 9 patients during and for 2 weeks after operation which required prolonged anesthesia. The values of serum total protein (TP), serum albumin (Alb) and COPm decreased by about 17% three hours after the start of anesthesia and by 15%, 20% and 24%, respectively, after 18 hours. These values returned to each preoperative value about one week after the operation. The correlation coefficients (the values in parentheses were calculated using data obtained during anesthesia) comparing COPm to TP, Alb and calculated colloid osmotic pressure (Landis' equation) were 0.661 (0.710), 0.480 (0.649) and 0.666 (0.727). There was no correlation between COPm and water balance. When COPm was 17.5mmHg or lower, calculated colloid osmotic pressure value was higher than COPm as the Alb/TP ratio decreased. Decreases in the values of COPm and serum protein during operation were considered to have been caused mainly by increased capillary permeability.

Anesthesia↗