Transarterial Embolization of Simple Pulmonary Arteriovenous Malformations: Long-Term Outcomes of 0.018-Inch Coils versus Vascular Plugs

PURPOSE

To compare the safety, effectiveness, and persistence rates of 0.018-inch coils with those of Amplatzer vascular plugs (AVPs; Abbott Vascular, Abbott Park, Illinois) for the treatment of pulmonary arteriovenous malformations (PAVMs) in response to a growing concern that 0.018-inch coil embolization would increase the long-term persistence rate.

MATERIALS AND METHODS

This is a retrospective, single-center study of a database (2002-2020) of 633 PAVM embolizations. Complex PAVMs and those not embolized with 0.018-inch coils or plugs were excluded. PAVM embolization material was classified into 4 groups: (a) 0.018-inch nonfibered coils (NFCs), (b) 0.018-inch fibered coils (FCs), (c) NFCs and FCs, or (d) plugs. Persistence was defined as flow through the PAVM on digital subtraction angiography (DSA) or as <30% diameter reduction of the aneurysmal sac on unenhanced computed tomography (CT). Kaplan-Meier analysis and Cox regression were used to assess PAVM's persistence-free survival.

RESULTS

A total of 312 PAVM embolizations with NFCs (43 PAVMs), FCs (127 PAVMs), NFCs and FCs (12 PAVMs), or plugs (130 PAVMs) in 109 patients (28% men; mean age = 49 years) were included. All PAVM embolizations were technically successful without any major adverse events. PAVM persistence-free survival rates at 10 years' follow-up were 40.8% versus 44.7% in the NFC and FC groups (P = .22) and 47.3% versus 81.0% in the 0.018-inch coil (NFC or FC) and plug groups (P < .0001), respectively. There were 0.43 (79/182) and 0.08 (10/130) re-embolization procedures per PAVM in the 0.018-inch coil and plug groups, respectively (P < .001).

CONCLUSIONS

PAVM embolization with 0.018-inch coils was safe, but persistence rate with PAVM embolization was significantly higher than that with plugs, with no significant differences between FCs and NFCs.

Safety, Efficacy and Mid-Term Outcome for Transarterial Embolization (TAE) of Renal Angiomyolipoma (AML) Using Ethylene Vinyl Alcohol Copolymer Liquid Embolic Agent (EVOH)

Transarterial embolization (TAE) of renal angiomyolipoma (AML) is effective in treating and preventing hemorrhage. We report our experience using EVOH with a single-center retrospective study of all AML embolized with EVOH between June 2013 and March 2022 at the Montpellier University Hospital. A total of 29 embolizations were carried out in 24 consecutive patients (mean age: 53.86 years; 21 women and 3 men) with 25 AMLs for severe bleeding, symptomatic AML, tumor size > 4 cm, or presence of aneurysm(s) > 5 mm. Data collected included imaging and clinical outcomes, tuberous sclerosis complex status, change in AML volume, rebleeding, renal function, volume and concentration of EVOH used, and complications. Out of 29 embolizations performed for 25 AMLs, four were performed in an emergency. Technical success was achieved for 24/25 AMLs. Mean AML volume reduction was 53.59% after a mean follow-up time of 446 days using MRI or CT scan. Aneurysms on angiogram and the symptomatological nature of AML, as well as secondary TAE and multiple arterial pedicles, were statistically associated (p < 0.05). Two patients (8%) underwent nephrectomy after TAE. Four patients had a second embolization. Minor and major complication rates were 12% and 8%, respectively. Neither rebleeding nor renal function impairment was noticed. TAE of AML using EVOH is, thus, highly effective and safe.

Artificial intelligence solution to classify pulmonary nodules on CT

PURPOSE

The purpose of this study was to create an algorithm to detect and classify pulmonary nodules in two categories based on their volume greater than 100 mm³ or not, using machine learning and deep learning techniques.

MATERIALS AND METHOD

The dataset used to train the model was provided by the organization team of the SFR (French Radiological Society) Data Challenge 2019. An asynchronous and parallel 3-stages pipeline was developed to process all the data (a data "pre-processing" stage; a "nodule detection" stage; a "classifier" stage). Lung segmentation was achieved using 3D U-NET algorithm; nodule detection was done using 3D Retina-UNET and classifier stage with a support vector machine algorithm on selected features. Performances were assessed using area under receiver operating characteristics curve (AUROC).

RESULTS

The pipeline showed good performance for pathological nodule detection and patient diagnosis. With the preparation dataset, an AUROC of 0.9058 (95% confidence interval [CI]: 0.8746-0.9362) was obtained, 87% yielding accuracy (95% CI: 84.83%-91.03%) for the "nodule detection" stage, corresponding to 86% specificity (95% CI: 82%-92%) and 89% sensitivity (95% CI: 84.83%-91.03%).

CONCLUSION

A fully functional pipeline using 3D U-NET, 3D Retina-UNET and classifier stage with a support vector machine algorithm was developed, resulting in high capabilities for pulmonary nodule classification.

Nodular reverse halo sign in active pulmonary tuberculosis: A rare CT feature?

PURPOSE

The purpose of this study was to investigate the prevalence of the nodular reverse halo sign (NRHS) in chest computed tomography (CT) in patients with active pulmonary tuberculosis.

MATERIALS AND METHODS

From March 2018 to March 2019, 29 consecutive patients with a culture-confirmed active pulmonary tuberculosis and who underwent chest CT examination during hospital-admission were retrospectively included in the study. There were 24 men and 5 women with a mean age of 40.9±16.7 (SD) years (range: 18-80years). Chest CT examinations of included patients were evaluated for the presence of NRHS and other tuberculosis-related CT signs.

RESULTS

CT revealed the NRHS in 5 patients (5/29; 17%). The other CT signs of tuberculosis included consolidations in 18 patients (18/29; 62%), tree-in-bud pattern in 14 patients (14/29; 48%), cavitation in 12 patients (12/29; 41%), sparse nodules in 10 patients (10/29; 34%), and pleural effusion in 8 patients (8/29; 28%).

CONCLUSION

CT shows NRHS in 17% of patients with active pulmonary tuberculosis, indicating that the sign is not as rare as previously thought in patients with this condition.

[Toxoplasma gondii: ultrastructural study of cystic formations observed in human fibroblast culture]

A strain of Toxoplasma gondii, non pathogenic to mice (Prugniaud strain) produced cyst-like stages when inoculated in human fibroblast culture. An ultrastructural study was performed in order to compare these cyst-like forms to brain cysts of the same strain and to intracellular clusters of tachyzoites observed in mice TG 180 sarcoma cells. Electron microscopy confirmed the similarities between brain cysts and cysts obtained in vitro.

Effects of glycerol injection into rat sciatic nerve

In recent years, injection of pure glycerol into the trigeminal cistern has been used for the treatment of trigeminal neuralgia. The mechanism of action of this therapy remains unclear. Using both light and electron microscopy, we investigated the effects of microinjections of sterile, pure glycerol into the endoneurium of the sciatic nerve of the rat. We observed total destruction of both myelinated and unmyelinated fibers. In nearly all animals, signs of automutilation were observed in the paralyzed limb. Histological evidence of nerve degeneration appeared soon after injection, with intense proliferation of perineurial cells that eventually divided the endoneurium into numerous microcompartments.

Acute pure sensory paraneoplastic neuropathy with perivascular endoneurial inflammation: ultrastructural study of capillary walls

We studied a patient with epidermoid carcinoma of the lung (treated surgically 1 year earlier) and an acute symmetric pure sensory neuropathy that regressed almost completely within 1 month. Superficial peroneal nerve biopsy 15 days after onset showed evidence of demyelination with perivascular endoneurial inflammation. On ultrastructural examination, lymphocytes were seen passing through endothelial cells of endoneurial capillaries.

Case of dementia and myoclonia in an adult associated with anomalies in polyunsaturated fatty acids in leukocytes and peripheral nerve. An ultrastructural study of peripheral nerve

We report a case of a 66-year-old patient presenting with abnormal movements and associated dementia. Death occurred 4 years after the onset of symptoms. In spite of the lack of autopsy results, the picture was one of late onset neuronal ceroid lipofuscinosis (Kufs' disease). Ultrastructural study of a peripheral nerve biopsy sample indicated a process of demyelination associated with unusual inclusions in Schwann cell cytoplasm. Biochemical analysis of the same sample and leukocytes showed considerable alterations in polyunsaturated fatty acid levels. These findings are discussed in the light of work on cases of infantile neuronal ceroid lipofuscinosis.

Familial Creutzfeldt-Jakob disease with extensive degeneration of white matter. Ultrastructure of peripheral nerve

A case of Creutzfeldt-Jakob disease (CJD) in a 52-year-old man is described. At post mortem, extensive involvement of white matter was seen. A few similar cases have been reported mainly by Japanese authors. Our patients belonged to a French family in which 14 cases of CJD over three generations have been recorded. One of the patient's first cousins also had extensive white matter involvement. This is an unusual panencephalopathic form of CJD. The causes of the involvement of white matter are unknown. There was no clinical evidence of neuropathy but an electron-microscopic study of biopsied superficial peroneal nerve showed it to be present. Study of peripheral nerves is suggested for all patients with CJD.

Nonviral intranuclear inclusions in a nerve biopsy: an ultrastructural study

During the ultrastructural study of a nerve biopsy from a diabetic patient suffering from chronic polyradiculoneuritis, we observed that a significant number of endoneural fibroblasts had abnormal nuclei. They contained a round, centrally located inclusion consisting of numerous irregularly arranged filaments approximately 15 nm in diameter. No such lesion in peripheral nerve has previously been reported. Interpretation of these abnormalities is difficult.

Peripheral nerve damage during multiple myeloma and Waldenstrom's macroglobulinemia: an ultrastructural and immunopathologic study

Peripheral nerve biopsies of 22 patients who were seen with a peripheral neuropathy were studied. On each occasion an ultrastructural study was performed and on 12 occasions an immunopathologic study was done. Ten patients had Waldenström's macroglobulinemia and 12 had multiple myeloma. Cellular infiltrates were observed in three cases of Waldenström's macroglobulinemia by light microscopy. A widening of the myelin sheath, corresponding to an accumulation of macroglobulin, was found in three cases of Waldenström's macroglobulinemia. The presence of abundant deposits of amyloid was noted in one case of multiple myeloma. These diverse features show the various possible mechanisms that can produce peripheral nerve damage during the course of malignant dysglobulinemias. The segmental demyelination is probably of immunologic origin. The axonal lesions cannot be explained satisfactorily except in those rare cases where amyloid deposits are present in the endoneurium.

Coexistence of minicores, cores, and rods in the same muscle biopsy. A new example of mixed congenital myopathy

The authors report on the ultrastructural study of a muscle biopsy carried out in a child 6 years after the first biopsy which had led to diagnosis of "multicore disease". Clinical evolution following a few years of muscular involvement had been favorable. The lesions observed in the second biopsy were again characterized by the presence of multicores, but in addition to cores and rods. All of these abnormalities could sometimes be noted in a single muscle fiber. Although rare cases of an association of two types of lesions have been reported, no study has hitherto shown multicores, cores, and rods in the same biopsy. This observation might confirm the possibility of common pathogenic mechanisms producing these lesions.

Abnormal proliferation of intraergastoplasmic microfilaments in myelinated schwann cells: ultrastructural study of two cases

We report the ultrastructural findings in superficial peroneal nerve biopsies in two patients, one with idiopathic sensory neuropathy and the other with the Guillain-Barré syndrome and Hodgkin's disease. In addition to demyelination, there was an intense proliferation of microfilaments within numerous vesicles of the endoplasmic reticulum of a great number of myelinated Schwann cells. This abnormality does not appear to have been previously reported in the literature. The mechanisms responsible for this finding are unknown.

Cryoglobulinemic neuropathy: ultrastructural study of the nerve capillaries

The authors report here the case of a female patient who developed symmetrical polyneuropathy of the lower limbs a few months after she was found to have a myeloma with cryoglobulinemia. In musculocutaneous nerve biopsy material from this patient, electron microscopy showed pathological changes in the nervous tissue together with axonal degeneration and demyelination. But the most striking finding was the presence in the endoneurial space, of numerous masses made up of closely packed tubular structures. These masses occurred also in the walls and even in the lumen of all the vasa nervorum. Their morphologic features and dimensions were identical to cryoprecipitate which the authors extracted from the serum and which they examined with electron microscope.

N-Hexane- and methylethylketone-induced polyneuropathy. Abnormal accumulation of glycogen in unmyelinated axons. Report of a case

This report presents the ultrastructural nerve study of a patient with sensorimotor neuropathy by a shoe glue containing an association of n-hexane and methylethylketone. Giant axons, distended by microfilamentous proliferation typical of such cases of neuropathy, were found in significant amounts. An unusual histological feature of this case was the considerable distension by a marked accumulation of glycogen granules in certain unmyelinated axons. Such a lesion has never been described in neuropathy induced by industrial agents.

Cryoglobulinemic neuropathy: a pathological study

A 53-year-old woman developed symmetrical polyneuropathy of the lower limbs a few months after she was found to have myeloma with cryoglobulinemia. In musculocutaneous nerve biopsy material, electron microscopy showed both axonal degeneration and demyelination. The most striking finding was the presence, in the endoneurial space, of numerous masses of closely packed tubular structures. These masses also were found in the walls of all the vasa nervorum and within the lumen of some vessels. The morphological features and dimensions of the deposits within nerve were identical to those of cryoprecipitates extracted from serum and examined with the electron microscope. An example of myeloma neuropathy with cryoglobulin deposits within the endoneurial space has not been reported previously.

Primary systemic amyloidosis. An electron microscopic study of the vitreous

We performed an electron microscopic study of the vitreous of a patient with primary systemic amyloidosis. Amyloid deposits were found using the technique previously used to differentiate amyloidosis in urinary sediments.

[Scanning electron microscopic study of the effect of some intraocular irrigating solutions on the corneal endothelium]

The effects of two intraocular irrigating solutions (physiological saline, Mac Carey-Kaufman medium) on the corneal endothelium of the rabbit have been evaluated by scanning electron microscopy. During an experimental anterior vitrectomy on aphakic rabbit eyes, corneas were perfused with a different solution in each eye during a period of up to 75 min and with a maximum of 250 cm3 of liquid. We found a significant difference only after 60 min of perfusion at which time important lesions appeared in the cornea of eyes perfused with physiological saline. The corneas irrigated with Mac Carey-Kaufman medium remained normal.

[Skin fibrosis in hyperthyroidism treated by sotalol and radioactive iodine (author's transl)]

The authors present detailed data about skin fibrosis appearing in hyperthyroidism treated by Sotalol and radioactive iodine. Cutaneous thickening is discovered quite rapidly when the patient is monitored daily (as in case 4). It is asymptomatic and no other features of scleroderma are found. Regression occurs within 4-10 months. Histologically, fibrosis is located in the entire dermis. Dermal appendages are normal and no inflammatory changes occur. No anomalies of collagen structure and fibroblasts have been observed ultrastructurally. Immunological studies (direct immunofluorescence of the skin, lymphocyte transformation and leucocyte migration tests with Sotalol) were normal. The mechanism is unknown, but an immunological or a toxic one is excluded; however a pharmacological action is possible. The role of other betablockers must be assessed by a randomised study.

[Conjunctival biopsies in diffuse amyloid (author's transl)]

Amyloid well known as a homogeneous eosinophilic material deposited in various body tissues. Conjunctival biopsies in four patients distributed among the different classical type of diffuse amyloidosis demonstrate the diagnostic value of this simple procedure. In all cases, by optic microscopy amyloid deposits were seen in the subepithelial connective tissue of the conjunctiva. Electron microscopy showed the characteristic fibrillar material of amyloid, with its fiber diameter of 9 to 12 nm in all cases. Since it is a totally harmless procedure, it seems obvious that each time systemic amyloidosis is suspected, conjunctival biopsy must be done first.

Hemosiderin deposition in muscle. Report of three cases

This report presents the morphological character of iron deposits in muscle biopsies of three patients who have been suffering from secondary hemochromatosis. The granules observed by light microscopy and located either in the cytoplasm of macrophages or inside muscle fibres are illustrated in electron micrographs. In this study, Thiery's technic, which is a specific and very sensitive reaction, has been very useful to confirm by electron microscopy that these granules contain iron. Such a study in muscle appears to be unique. In our experience, accumulation of hemosiderin pigment in muscle does not seem to be specific of any disease but suggests that a hepatic biopsy must be done.