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PubMed1979

Talc emboli and retinal neovascularization in a drug abuser.

A 38-year-old male drug abuser had multiple emboli in the retinal circulation of the posterior pole of both eyes. He showed widespread peripheral retinal capillary nonperfusion and neovascular proliferation at the junction of perfused and nonperfused retina. The emboli were considered to be talc particles from the intravenous administration of suspensions of oral medications. The presumed mechanism of development of neovascularization in this case was the filtering out of the particles by the retinal vasculature with vaso-occlusion, ischemia and subsequent retinal neovascularization.

Adult↗
PubMed1979

Disk and peripheral retinal neovascularization secondary to talc and cornstarch emboli.

A 30-year-old man was examined because of blurred vision. The symptoms had occurred immediately after the patient had injected himself intravenously with crushed, unfiltered, methylphenidate HCl (Ritalin) tablets. Fine yellow-white crystals were scattered throughout the retin of both eyes. The crystals were presumed to be talc emboli. Disk and peripheral retinal neovascularization were present. Fluorescein angiography revealed widespread retinal capillary nonperfusion. This is the first reported case, to the best of my knowledge, of disk neovascularization occurring after intravenously injected, crushed, unfiltered, methylphenidate HCl tablets.

Adult↗
PubMed1992

Early and late outcome after diagnostic thoracoscopy and talc pleurodesis.

Although thoracoscopy is now recognized to be of both diagnostic and therapeutic value, the risks of this procedure have not been fully addressed. We retrospectively reviewed our experience with 100 patients who underwent 110 thoracoscopies during the period January 1989 to February 1991. Sixty-five men and 35 women (ratio of 1.9:1) underwent thoracoscopy using general anesthesia and intubation with a double-lumen endotracheal tube. The mean age was 64.2 +/- 11.6 years (range, 13 to 85 years). The diagnosis was established in 48 (85.7%) of the 56 patients with undiagnosed pleural effusions. Forty-four patients were referred for therapeutic thoracoscopic talc pleurodesis. Pleurodesis was successful in 42 patients (95.5%). Four patients (4%) had five postoperative complications (two bronchopleural fistulas, two chest infections, and one arrhythmia). Five patients (5%) died after thoracoscopy; mean age was 67.8 +/- 8.1 years (range, 55 to 77 years). The causes of death were cardiac arrest in 2, respiratory failure in 1, and malignant cachexia in 2. The findings of this study confirm that thoracoscopy can achieve high rates of diagnostic and therapeutic success but is not without attendant mortality in a high-risk patient population.

Aged↗
PubMed1990

Pulmonary toxicity of inhaled and intravenous talc.

Talc (magnesium silicate) is a widely used, generally considered benign substance. It is principally used as an inert filler material in drug tablets or as a drying ingredient in baby powders. However, in both cases inappropriate use can lead to severe pulmonary toxicological responses. On the one hand, intravenous injection of 'solubilized', CNS active pills can produce microemboli in small pulmonary vessels. This can lead to various degrees of granuloma formation, compromised pulmonary function, or death. Overzealous application of baby powder can also produce severe pulmonary complications if the infant inspires the powder. Although the data are relatively scarce, a number of reports suggest the existence of a chronic problem in this area.

Granuloma↗
PubMed1994

Effects of magic-angle spinning on spin-lattice relaxations in talc.

The spin-lattice relaxation times T1 of 1H and 29Si spins in talc have been measured at room temperature with and without magic-angle spinning (MAS) of the sample. Paramagnetic impurities work as relaxation centers. 1H T1 depends on the spinning rate, whereas 29Si T1 is independent of the spinning rate. These facts demonstrate that spin diffusion plays an important role in 1H relaxation but not in 29Si relaxation. 29Si spins relax through dipole-dipole interactions with electron spins directly, which mechanism is not affected by spinning. The relaxation rates have been analyzed theoretically.

Magnetic Resonance Spectroscopy↗
PubMed2005

The surface energy of talc.

The determination of an average value for the surface energy of talc (gammaS) via solid-water interfacial interactions is described. It is based on a formula obtained by the combination of the Young equation with a general equation of pair interaction. Important features of the method are (a) the use of the Young equation to determine the range where the value of the surface energy lies and (b) the determination of the mean value within this range using a probability function. The value found is 217.31 mJ m(-2) in the range 193.36-257.43 mJ m(-2).

Adsorption↗
PubMed2006

[Bilateral Chylothorax after delivery: an infrequent case treated with videothoracoscopic talc pleurodesis].

Bilateral chylothorax after delivery is a highly infrequent entity. We present the case of a 28-year-old woman who developed progressive dyspnea due to bilateral milky pleural effusion several months after delivery. The effusion was found to contain chylomicrons in the biochemical analysis. Initial conservative treatment failed twice and the chylothorax was successfully treated through sequential bilateral videothoracoscopy with an interval of 6 days between the two interventions and pleurodesis with spray talc.

Adult↗
PubMed1983

Epidemic of haemorrhagic disease in Vietnamese infants caused by warfarin-contaminated talcs.

In August, 1981, paediatric hospitals in Ho Chi Minh City (formerly Saigon), Vietnam, began to report cases of a haemorrhagic syndrome in infants. The cause of this haemorrhagic phenomenon was identified as talcum powder contaminated with the anticoagulant warfarin. Analysis of talcum powders revealed warfarin in concentrations between 1.7% and 6.5%. 741 cases were detected and 177 patients died. The possibility of accidental contamination or substitution of a perfuming agent by warfarin can be rejected. In an experiment with two baboons, the animal exposed to the contaminated talc died five days later from haemorrhage. The accident and the animal study demonstrate the significant transcutaneous uptake of the anticoagulant.

Animals↗
PubMed2002

Prolonged pleural effusion following Fontan operation: effective pleurodesis with talc slurry.

Prolonged pleural effusions following a Fontan operation are a difficult problem. Although fenestrations and embolizations of systemic-pulmonary artery collaterals were suggested to treat and to decrease the risk of this complication, talc slurry pleurodesis may successfully augment and accelerate the beneficial effects of those techniques against the resistant effusions.

Adolescent↗
PubMed1998

[Malignant pleural effusions: recourse to early use of talc].

INTRODUCTION: Our purpose was to assess the efficacy, permanence and safety of thoracoscopic talc poudrage (TTP) for pleurodesis in malignant effusions. We report the follow-up of 360 patients who received TTP in two centers in Marseille (France). CURRENT KNOWLEDGE AND KEY POINTS: Eighty-eight patients presented with mesothelioma and 272 had pleural metastasis. The mean follow-up time was 12 months (range: 2-120). Out of the 327 patients whose response could be evaluated, 90.2% had a successful pleurodesis at 1 month, and 82.1% had a life-long pleural symphysis. Adverse effects included one death 3 days after the procedure in an end-stage patient, fever (9.8%), infection of the parietal scar (2.5%) and pulmonary infection (0.8%). FUTURE PROSPECTS AND PROJECTS: TTP is an effective and safe method of life-long pleurodesis. It should be performed early on in the history of malignant effusions to avoid failures of the technic, mainly linked to trapped lung and to the general condition of patients.

Adenocarcinoma↗
PubMed1997

Mechanistic evaluation of binary effects of magnesium stearate and talc as dissolution retardants at 85% drug loading in an experimental extended-release formulation.

The feasibility of producing extended-release matrix tablets with high drug loadings (80-90% w/w) containing a binary combination of magnesium stearate (MS) and talc (T) at different levels as major dissolution retardants was investigated. Matrix tablets were prepared from a granulation containing theophylline, starch, hydroxypropylcellulose, and varying amounts of MS and T. Using a 32 factorial design, the effect of MS and T levels on the physical properties and drug release characteristics of the tablets was evaluated. Response surface analysis showed that the binary combination of MS and T at levels >3% adversely affected both tensile strength and friability. A parabolic relationship was observed for the increase in time required for the release of 50% of the theophylline (t50%) with increased MS levels. Moreover, as the proportion of MS and T was increased, the release profiles became more linear. A combination of 3% MS and T provided both near zero-order release kinetics as well as a coherent matrix structure. Based on model fitting, a release mechanism combining diffusion and matrix erosion/dissolution is proposed. It may be concluded that in the development of controlled-release systems, the binary combination of MS and T at levels exceeding those conventionally used for lubrication can be employed as an inexpensive, low bulk dissolution retardant for formulations with high drug loading.

Chemical Phenomena↗
PubMed2002

Talc retinopathy.

A 45 year old man presented with talc retinopathy that had been present for decades. The static nature of this condition indicates that, in the absence of ongoing intravenous drug use, ophthalmological follow up is not necessary

Fluorescein Angiography↗
PubMedDate not supplied

Thoracoscopic talc pleurodesis for malignant pleural effusion.

BACKGROUND: Malignant pleural effusion (MPE) is a common and distressing condition at the end of life for many patients with disseminated cancer. The challenge for the surgeon lies in managing this problem in order to deliver the most effective palliation with the least impact on the limited time available to these patients. METHODS: Herein is reported a retrospective review of outcomes for a consecutive series of 66 MPE (61 patients) treated over a 5-year period from 1995 to 2000. A standard operative technique involving a single-lung anaesthetic and two-port thoracoscopy was employed. Outcomes were determined by contacting the referring practitioner or the patients themselves. Principal outcome measures included time to recurrence of the effusion and survival. RESULTS: Complete follow up was achieved for 60 MPE (55 patients; five of whom were treated for metachronous, bilateral disease). The three most common primary sites were breast, lung and mesothelial tissue. The planned procedure was not completed in two cases due to encasement of the underlying lung by tumour. Primary failure (immediate recurrence of the effusion) occurred in six cases. Delayed recurrence of the effusion occurred in a further 23 MPE resulting in complete control in 31 cases (52%) until death. Overall median survival was 220 days and the 30-day mortality was 0. CONCLUSIONS: Complete and permanent control of a malignant effusion is difficult to achieve. Management based on thoracoscopy and talc insufflation produces satisfactory results with an acceptable morbidity and no early mortality. The ability to inspect the pleural space, break down adhesions and completely drain pockets of fluid to achieve complete lung expansion probably contributes to this.

Adult↗
PubMed2002

Assessment of historical exposures to talc at a mining and milling facility.

The purpose of this study was to develop an estimate of exposure to respirable dust for all job categories and all years in a retrospective follow-up study of worker mortality in a talc mining and milling facility. All jobs were assigned to work areas that were considered to have similar exposure profiles. Uniform exposure time periods during which non-random, deterministic variables were thought to be constant were identified and an experienced rater assigned categorical exposure scores to each work area/time period. These scores and measured baseline respirable dust concentrations were used to calculate the estimated job area/year concentrations for each work area/time period. Estimates were compared to available historical measurements. The estimated exposures ranged from 1.7 to 0.1 mg/m(3) and displayed a decreasing trend over time. When compared with measured exposures, the estimated exposures had a correlation coefficient of 0.55 with an average difference of 0.01 mg/m(3) and a range of 0.60 to -0.48 mg/m(3). The estimates were considered to be acceptable for determining relative ranking of subjects according to cumulative exposure.

Follow-Up Studies↗
PubMed1991

Talc retinopathy.

We present five case reports of the clinical manifestations of talc retinopathy. Photographs illustrate the typical intravascular location of these crystalline deposits which are evident only after repeated injections of street drugs. Discussion includes differential diagnosis, systemic complications, and ophthalmic management of this condition.

Adult↗
PubMed1980

Gallium scans and serum angiotensin converting enzyme levels in talc granulomatosis and lymphocytic interstitial pneumonitis.

We have described two patients who had positive gallium lung scans with simultaneous elevation in serum angiotensin converting enzyme (SACE) levels. One patient had talc granulomatosis secondary to the intravenous injection of pentazocine, while the other patient had lymphocytic interstitial pneumonitis. We believe these are the first cases in which a positive gallium scan and elevated SACE levels were associated with these entities.

Adult↗
PubMed1991

Talc granulomatosis presenting as spontaneous pneumothorax.

Spontaneous pneumothorax has been described in association with conglomerate masses and bullous disease in end-stage talc granulomatosis. Our case demonstrates that pneumothorax can occur earlier in the course of the disease before these end-stage radiographic changes are present.

Adult↗