1
|
Geavlete P, Multescu R, Mares C, Buzescu B, Iordache V, Geavlete B. Retrograde Intrarenal Surgery for Lithiasis Using Suctioning Devices: A Shift in Paradigm? J Clin Med 2024; 13:2493. [PMID: 38731026 PMCID: PMC11084153 DOI: 10.3390/jcm13092493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2024] [Revised: 04/12/2024] [Accepted: 04/20/2024] [Indexed: 05/13/2024] Open
Abstract
New suction endoscopes, ureteral access sheaths (UAS) and catheters aim to improve the efficacy of flexible ureteroscopy and optimize its safety. Suction UAS with non-flexible tips have shown promising results, especially in maintaining low intrarenal pressure, but also in removing small debris and reducing the "snow globe" effect. In addition, suctioning UAS with a flexible tip offers the advantage of being able to be navigated through the pyelocaliceal system to where the laser lithotripsy is performed. It can also remove small stone fragments when the flexible ureteroscope is retracted, using the Venturi effect. Direct in-scope suction (DISS) involves aspirating dust and small stone debris through the working channel of a flexible ureteroscope, thus regulating intrarenal pressure and improving visibility. Steerable aspiration catheters are other devices designed to increase stone clearance of the pyelocaliceal system. They are inserted under fluoroscopic guidance into every calyx after retraction of the flexible ureteroscope, alternating irrigation and aspiration to remove dust and small gravels. Combining flexible-tip suction UAS and the DISS technique may offer some advantages worth evaluating. The advantage of using these instruments to achieve a low intrarenal pressure was demonstrated. The true practical impact on the long-term stone-free status is a matter requiring further studies.
Collapse
Affiliation(s)
- Petrisor Geavlete
- Department of Urology, “Saint John” Emergency Clinical Hospital, 042122 Bucharest, Romania; (P.G.); (V.I.); (B.G.)
- Faculty of General Medicine, University of Medicine and Pharmacy, ‘Carol Davila’ Bucharest, 050474 Bucharest, Romania
| | - Razvan Multescu
- Department of Urology, “Saint John” Emergency Clinical Hospital, 042122 Bucharest, Romania; (P.G.); (V.I.); (B.G.)
| | - Cristian Mares
- Department of Urology, “Saint John” Emergency Clinical Hospital, 042122 Bucharest, Romania; (P.G.); (V.I.); (B.G.)
- Faculty of General Medicine, University of Medicine and Pharmacy, ‘Carol Davila’ Bucharest, 050474 Bucharest, Romania
| | - Bogdan Buzescu
- Department of Urology, “Saint John” Emergency Clinical Hospital, 042122 Bucharest, Romania; (P.G.); (V.I.); (B.G.)
- Faculty of General Medicine, University of Medicine and Pharmacy, ‘Carol Davila’ Bucharest, 050474 Bucharest, Romania
| | - Valentin Iordache
- Department of Urology, “Saint John” Emergency Clinical Hospital, 042122 Bucharest, Romania; (P.G.); (V.I.); (B.G.)
| | - Bogdan Geavlete
- Department of Urology, “Saint John” Emergency Clinical Hospital, 042122 Bucharest, Romania; (P.G.); (V.I.); (B.G.)
- Faculty of General Medicine, University of Medicine and Pharmacy, ‘Carol Davila’ Bucharest, 050474 Bucharest, Romania
| |
Collapse
|
2
|
Mares C, Geavlete P, Ene C, Iordache V, Geavlete B. Semirigid vs Flexible Ureteroscopy in the Management of Ureteral Stones - Review. Maedica (Bucur) 2023; 18:490-497. [PMID: 38023749 PMCID: PMC10674128 DOI: 10.26574/maedica.2023.18.3.490] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2023]
Abstract
Ureteral stones are a major clinical problem in urology that require effective and safe therapeutic options. Semirigid and flexible ureteroscopy ar two well-established procedures for treating these stones. The present review provides an outline of the advantages and disadvantages of these approaches. Semirigid ureteroscopy, which uses a rigid straight instrument, provides excellent stone visualisation and successful fragmentation. It is especially useful for proximal and bigger stones, frequently resulting in high stone-free rates and reduced procedure times. Nonetheless, its stiffness can make it difficult to navigate the delicate ureteral anatomy and increase the risk of mucosal injury. On the other hand, flexible ureteroscopy employs a more adjustable flexible scope, allowing access to complicated ureteral configurations while reducing the risk of ureteral trauma. It excels at treating distal and difficult stones but has a lower efficacy with larger stones and often requires longer procedure times. The choice between semirigid and flexible ureteroscopy is determined by patient-specific factors such as stone characteristics or anatomical considerations and the surgeon's skill. A customised approach that uses the capabilities of both treatments as needed can improve stone management outcomes while reducing potential problems. The continued advancement of technology and methodological modifications is predicted to improve the field of ureteroscopic stone management.
Collapse
Affiliation(s)
- C Mares
- "Carol Davila" University of Medicine and Pharmacy, Bucharest, Romania
- "Saint John" Emergency Clinical Hospital, Department of Urology, Bucharest, Romania
| | - P Geavlete
- "Carol Davila" University of Medicine and Pharmacy, Bucharest, Romania
- "Saint John" Emergency Clinical Hospital, Department of Urology, Bucharest, Romania
- Sanador Hospital, Bucharest, Romania
| | - C Ene
- "Carol Davila" University of Medicine and Pharmacy, Bucharest, Romania
- "Saint John" Emergency Clinical Hospital, Department of Urology, Bucharest, Romania
| | - V Iordache
- "Saint John" Emergency Clinical Hospital, Department of Urology, Bucharest, Romania
| | - B Geavlete
- "Carol Davila" University of Medicine and Pharmacy, Bucharest, Romania
- "Saint John" Emergency Clinical Hospital, Department of Urology, Bucharest, Romania
- Sanador Hospital, Bucharest, Romania
| |
Collapse
|
3
|
Geavlete P, Plesuvescu A, Stanescu F, Ene C, Popescu R, Iordache V, Geavlete B. The Management of Reno-Ureteral Lithiasis - from Emergency Presentation to Definitive Treatment. Maedica (Bucur) 2023; 18:111-116. [PMID: 37266472 PMCID: PMC10231168 DOI: 10.26574/maedica.2023.18.1.111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Introduction: The aim of our study was to retrospectively evaluate the stone-free rate after the second intervention for every performed procedure (semirigid ureteroscopy, flexible ureteroscopy, semirigid plus flexible ureteroscopy and percutaneous nephrolithotomy). Materials and methods: A total of 149 patients, who came to the emergency room of "Saint John" Emergency Clinical Hospital, Bucharest, Romania, with acute renal pathology suggesting the presence of renal and/or ureteral lithiasis confirmed by imagining (x-ray, ultrasonography or computer tomography), were included in this retrospective study, which was conducted between September 2021 and September 2022. All selected patients had an indication of emergency surgical intervention that consisted of a double-J stent mounting. We analyzed the stone-free rate after the secondary intervention, which was one of the following procedures: semirigid ureteroscopy, flexible ureteroscopy, combined semirigid and flexible ureteroscopy (F-URS), and percutaneous nephrolithotomy (PCNL). Patients came back for the secondary intervention and were reevaluated using imaging techniques. Results:Endoscopic procedures were performed by 14 surgeons over a time period of two to six weeks after the initial stenting procedure. Encrusted stents were encountered in four cases and in five cases the patients were admitted with obstruction of previously inserted stents. From the total of 149 patients, 68 (45,6%) subjects underwent semirigid ureteroscopy, with a stone-free rate of 86% (59 cases), 32 (21,4%) F-URS, with a stone-free rate of 90,6% (30 cases), 41 (27,5%) combined flexible and semirigid ureteroscopy, with a stone-free rate of 90,24% (37 cases), and eight (5,3%) patients received PCNL, with a stone-free rate of 75% (six cases). Overall stone-free rate for all procedures was 90,06%. The mean operative time was 23 minutes. No major incidents or complications occurred during the procedures. Conclusion:The emergency pre-stenting before the definitive treatment of reno-ureteral lithiasis is a safe procedure. Flexible ureteroscopy was the most successful secondary intervention, with the highest rate of achieving stone-free status.
Collapse
Affiliation(s)
- P Geavlete
- "Carol Davila" University of Medicine and Pharmacy, Bucharest, Romania
- Urology Department, "Saint John" Emergency Clinical Hospital, Bucharest, Romania
- Sanador Hospital, Bucharest, Romania
| | - A Plesuvescu
- Urology Department, "Saint John" Emergency Clinical Hospital, Bucharest, Romania
| | - F Stanescu
- Urology Department, "Saint John" Emergency Clinical Hospital, Bucharest, Romania
| | - C Ene
- "Carol Davila" University of Medicine and Pharmacy, Bucharest, Romania
- Urology Department, "Saint John" Emergency Clinical Hospital, Bucharest, Romania
| | - R Popescu
- "Carol Davila" University of Medicine and Pharmacy, Bucharest, Romania
- Urology Department, "Saint John" Emergency Clinical Hospital, Bucharest, Romania
| | - V Iordache
- Urology Department, "Saint John" Emergency Clinical Hospital, Bucharest, Romania
| | - B Geavlete
- "Carol Davila" University of Medicine and Pharmacy, Bucharest, Romania
- Urology Department, "Saint John" Emergency Clinical Hospital, Bucharest, Romania
- Sanador Hospital, Bucharest, Romania
| |
Collapse
|
4
|
Geavlete B, Popescu RI, Multescu R, Iordache V, Popa GA, Georgescu D, Geavlete P. Bilateral same-session flexible ureteroscopy for renal stones: a feasible method. J Med Life 2022; 15:284-291. [PMID: 35419108 PMCID: PMC8999109 DOI: 10.25122/jml-2021-0385] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Accepted: 01/13/2022] [Indexed: 11/18/2022] Open
Abstract
A staged ureteroscopic procedure is generally preferred to treat bilateral renal stones. In this study, we evaluated the feasibility of bilateral same-session flexible ureteroscopy (BS-fURS) in renal stones. A total of 81 patients underwent bilateral BS-fURS between March 2014 and March 2021 for bilateral renal stones. The mean stone burden per patient was 17±4 (range 7-27 mm). The average stone density was 1240 HU (970 to 1510). We used 4 types of ureteroscopes: Olympus URF-V2 (34 cases), Storz Flex X2 (30 cases), single-use PUSEN PU 3022 (12 cases), and single-use PUSEN - PU 3033A (5 cases). We specifically set our Holmium laser for dusting, pop-corning, and fragmenting. We found 31 calcium oxalate monohydrate cases, 11 calcium oxalate dehydrate cases, 17 uric acid cases, and 22 magnesium ammonium phosphate cases. The mean operating time was 77 min. (range 52 to 85) for both renal units. The SFRs were evaluated between 1 and 3 months with computed tomography (fragments >3 mm were defined as residual). Double J stenting (6Fr.) was applied bilaterally in 8 cases (9.87%) and unilateral in 34 cases (41.97%). The overall SFRs after 1 and 2 procedures were 81.48% (66/81 cases) and 92.59% (75/81 cases), respectively. Postoperative complications after an overall 96 procedures were Clavien I-II (18.75%) and Clavien III (3.12%). Urinary tract infections were observed in 13 cases (16.04%) without any case of urosepsis. Our experience suggested some BS-fURS advantages as a single anesthetic session and potentially reduced cost associated with treatment. BS-fURS seem feasible, especially for medium-sized bilateral renal stones in high-volume centers.
Collapse
Affiliation(s)
- Bogdan Geavlete
- Department of Urology, Sanador Hospital, Bucharest, Romania,Department of Urology, Sf. Ioan Clinical Emergency Hospital, Bucharest, Romania
| | - Razvan-Ionut Popescu
- Department of Urology, Sf. Ioan Clinical Emergency Hospital, Bucharest, Romania,Corresponding Author: Razvan-Ionut Popescu, Department of Urology, Sf. Ioan Clinical Emergency Hospital, Bucharest, Romania. E-mail:
| | - Razvan Multescu
- Department of Urology, Sanador Hospital, Bucharest, Romania,Department of Urology, Sf. Ioan Clinical Emergency Hospital, Bucharest, Romania
| | - Valentin Iordache
- Department of Urology, Sanador Hospital, Bucharest, Romania,Department of Urology, Sf. Ioan Clinical Emergency Hospital, Bucharest, Romania
| | - Gelu-Adrian Popa
- Department of Radiology and Medical Imaging, Sf. Ioan Clinical Emergency Hospital, Bucharest, Romania
| | - Dragos Georgescu
- Department of Urology, Sanador Hospital, Bucharest, Romania,Department of Urology, Sf. Ioan Clinical Emergency Hospital, Bucharest, Romania
| | - Petrisor Geavlete
- Department of Urology, Sanador Hospital, Bucharest, Romania,Department of Urology, Sf. Ioan Clinical Emergency Hospital, Bucharest, Romania
| |
Collapse
|
5
|
Abstract
Introduction: Horseshoe kidney (HSK) is one of the most frequent renal malformations which appears to present an increased risk of stone formation caused by abnormal urine drainage. This study aims to compare the results of single-use flexible ureteroscopy (SUfURS) vs reusable devices (RfURS) with holmium laser in treating stones in HSK cases. Material and method: Between February 2017 and June 2021, 29 patients diagnosed with renal stone disease and horseshoe kidney were retrospectively analyzed. Subjects were divided into two groups: Group 1 (14 patients) undergoing SUfURS and Group 2 (15 patients) operated with RfURS devices. We analyzed the mean stone burden, operation time, stone free rate and complications. The surgical equipment was represented by the SUfURS PU3022 (Zhuhai Pusen Medical Technology) and RfURS URF-V2 (Olympus). Results: The two groups had a similar mean stone burden: 22 ± 6 mm (range 15-31 mm) for Group 1 and 24 ± 7 mm (range 16-30 mm) for Group 2. The average operative time was better for Group 1 (86 ± 17 min) vs Group 2 (89 ± 20 min). The stone-free status was similar for both groups after the first session (57.14% for Group 1 vs 53.33% for Group 2) and slightly in favor of Group 1 as compared to Group 2 (85.71% vs 73.33%, respectively) after the second session. The overall complication rate (Grades I, II and III) was almost similar in both groups, with a slightly prevalence for Group 1 (no major complications Grade IV and V). Conclusion:Flexible ureteroscopy represents an effective alternative treatment technique for large stones in kidney abnormalities. single-use flexible ureteroscopy can be successfully used to treat patients with genetically renal malformations and its results may be slightly better than those provided by using RfURS devices.
Collapse
Affiliation(s)
| | - Razvan Popescu
- "Saint John" Emergency Clinical Hospital, Department of Urology, Bucharest, Romania
| | | | | |
Collapse
|
6
|
Geavlete B, Iordache V, Geavlete P. Première expérience avec le nouvel urétéroscope souple à usage unique–sufurs, PU 3033A, 7,5 FR. Prog Urol 2021. [DOI: 10.1016/j.purol.2021.08.193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
|
7
|
Geavlete B, Ene C, Iordache V, Geavlete P. Initial Experience with the New Super Thin Single-use Pusen Flexible Ureteroscope 7.5 Fr in Renal Stones Endoscopic Treatment. Chirurgia (Bucur) 2021; 116:354-360. [PMID: 34191717 DOI: 10.21614/chirurgia.116.3.354] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/01/2021] [Indexed: 11/23/2022]
Abstract
Introduction: Single-use flexible ureteroscopes (SU-fURS) seems to overcome the main limitations of conventional reusable ureteroscopes in terms of acquisition and maintenance costs and breakages. Our aim was to analyz the efficiency and safety of the thinnest single use flexible scope from Pusen: Uscope Pusen, PU 3033A (Tip = 7.5 Fr.). Material and Methods: We analyzed data from 24 patients with pyelocaliceal stones from January to March 2021. The mean age of the patients was 49 years (range 27 to 71 years). There were unique stones, 7 pyelic, 10 in inferior calyx, 4 in the middle calyx and 3 in superior calyx. The average stone size (larger diameter) was 18 mm (12-26 mm). We used Uscope Pusen 7.5 Fr. (PU 3033A) and Dornier Medilas H Solvo laser. In all cases we applied no touch technique (NTT). We did't used CArm for progression control of the ureteroscope. We evaluated the patients for stone-free rate (SFR), mean operation time and complication rate. Results: The average operative time was 72 +- 21 minutes, range 66-131 min. For all 24 patients we didn't use wires or ureteral access sheath (NTT). Concerning the laser settings for dusting we used low energy: 0.5J, high frequency: 50 Hz, for pop-corning we used high energy: 1 J, medium frequency: 10-50 Hz, and for fragmenting high energy: 1 J, low frequency: 10 Hz. The stone-free status (residual fragments under 3 mm.) after one month was 91,7%. In 2 patients we need the second session with completely dusting of the residual stones. The visibility was optimal and we didn't describe any mucosal lesions of the ureter when we retired the scope. The intrarenal maneuverability was very good. Clavien I and II occurred in 6 patients. Conclusions: This new SU-fURS (7.5 Fr.) seems to be very effective and safe offering us an easy NTT. No ureteral damage and one day surgery are the main real minimally invasive characteristics of this ureteroscope.
Collapse
|
8
|
Iordache V, Minea M, Gheorghiu RA. Considerations for using ZigBee technology in vehicular non-critical applications. ANNALS OF COMPUTER SCIENCE AND INFORMATION SYSTEMS 2017. [DOI: 10.15439/2017f30] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
|
9
|
Iordache V, Gheorghiu RA, Minea M. Analysis of Interferences in Data Transmission for Wireless Communications Implemented in Vehicular Environments. Proceedings of the 2017 Federated Conference on Computer Science and Information Systems 2017. [DOI: 10.15439/2017f284] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
|
10
|
Geavlete P, Saglam R, Georgescu D, Multescu R, Iordache V, Kabakci A, Ene C, Geavlete B. Robotic flexible ureteroscopy versus classic flexible ureteroscopy in renal stones: Initial experience. ACTA ACUST UNITED AC 2016. [DOI: 10.1016/s1569-9056(16)30281-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
|
11
|
Geavlete P, Saglam R, Georgescu D, Mulţescu R, Iordache V, Kabakci AS, Ene C, Geavlete B. Robotic Flexible Ureteroscopy Versus Classic Flexible Ureteroscopy in Renal Stones: the Initial Romanian Experience. Chirurgia (Bucur) 2016; 111:326-329. [PMID: 27604670] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/01/2016] [Indexed: 06/06/2023]
Abstract
INTRODUCTION Roboflex Avicenna represents a new device for flexible ureteroscopy, able to provide an efficient lithotripsy for renal calculi, Bucharest being the fourth place in the world where such a device is already in use. MATERIAL AND METHODS The study was prospective and included a number of 132 patients equally randomized which underwent standard flexible ureteroscopy and robotic flexible ureteroscopy for renal calculi between July and February 2016. All the procedures were performed with aStorz XC flexible ureteroscope in association with Avicenna Roboflex. Stone fragmentation was performed using a Dornier Medilas 20H, Holmium Laser of 20 watt power and 2.1 µm wavelength. RESULTS The mean age was 48 years (range 26-77 years) and the mean stone size was 2.1 cm (range 1.1-3.6 cm) for the first group (FURS), while for the second one (robotic FURS) the mean age was 51 years (range 25-74 years) and the mean stone size was 2.4 cm (range 1.0-3.7 cm). The fragmentation time of the stones was better for robotic FURS (37 min versus 39 min). After 3 months, the stone free rate was 89.4% versus 92.4%, that representing a performance of the robotic technique over the classical one. In some cases were noticed residual fragments smaller than 3 mm, in 13.6% of patients who underwent FURS, respectively in 12.1% of robotic FURS cases. CONCLUSIONS The robotic treatment of kidney stones represents a comparative alternative to flexible ureteroscopy, with overall similar outcomes.
Collapse
|
12
|
Mavrodin C, Pariza G, Iordache V, Iorga P, Sajin M. Pseudomixoma peritonei, a rare entity difficult to diagnose and treat - case report. Chirurgia (Bucur) 2014; 109:846-849. [PMID: 25560512] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/01/2014] [Indexed: 06/04/2023]
Abstract
The authors present the case of a 56 year-old patient diagnosed with pseudomyxoma peritonei, 4 years after being subjected to a left adnexectomy for ovarian cystadenoma. The intra-parietal insemination of the mucinous cells enabled the development,at this level, of a gelatinous mass that raised problems of differential diagnosis with irreducible incisional hernia. In what regards the preoperative signs of clinical and paraclinical diagnosis we consider them obscure and nonspecific. The abdominal computed tomography revealed the presence of a massive intraperitoneal collection, but given the rarity of this pathology the initial diagnosis was made in the course of the exploratory laparotomy. Intraoperatively it became necessary to perform the omentectomy and total hysterectomy with contralateral adnexectomy and appendectomy. The histopathological examination confirmed the diagnosis. Using cisplatin associated with aggressive surgical cytoreduction this case of pseudomixoma had a good long-term evolution. The diagnosis was a challenge, and the nonspecific slow evolution of the disease led to difficult differential diagnostic.
Collapse
|
13
|
Abstract
UNLABELLED In the frame of the French national research program PRIMEQUAL (inter-ministry program for better air quality in urban environments), measurements of outdoor and indoor pollution have been carried out in eight schools in La Rochelle (France) and its suburbs. The buildings were naturally ventilated by opening the windows, or mechanically ventilated, and showed various air permeabilities. Ozone, nitrogen oxides (NO and NO(2)), and airborne particle (particle counts within 15 size intervals ranging from 0.3 to 15 mum) concentrations were continuously monitored indoors and outdoors for two 2-week periods. The indoor humidity, temperature, CO(2) concentration (an indicator of occupancy), window openings and building permeability were also measured. The temporal profiles of indoor and outdoor concentrations show ozone and nitrogen oxides behave differently: NO and NO(2) indoor/outdoor concentration ratios (I/O) were found to vary in a range from 0.5 to 1, and from 0.88 to 1, respectively, but no correlation with building permeability was observed. On the contrary, I/O ratios of ozone vary in a range from 0 to 0.45 and seem to be strongly influenced by the building air-tightness: the more airtight the building envelope, the lower the ratio. Occupancy, through re-suspension of previously deposited particles and possible particle generation, strongly influences the indoor concentration level of airborne particles. However, this influence decreases with particle size, reflecting the way deposition velocities vary as a function of size. The influence of particle size on deposition and penetration across the building envelope is also discussed by analyzing the I/O ratios measured when the buildings were unoccupied, by comparing the indoor concentrations measured when the buildings were occupied and when they were not (O/U ratios), and by referring to previously published studies focussing on this topic. Except one case, I/O were found to vary in the range from 0.03 to 1.79. All O/U are greater than one and increase up to 100 with particle size. PRACTICAL IMPLICATIONS Assessing children's total exposure requires the knowledge of outdoor and indoor air contaminant concentrations. The study presented here provides data on compared outdoor and indoor concentration levels in school buildings, as well as information on the parameters influencing the relationship between outdoor and indoor air quality. It may be used as a basis for estimating indoor concentrations from outdoor concentrations data, or as a first step in designing buildings sheltering children against atmospheric pollution.
Collapse
Affiliation(s)
- P Blondeau
- LEPTAB, University of La Rochelle, La Rochelle cédex, France.
| | | | | | | | | |
Collapse
|
14
|
Cernea P, Iordache V. [Avulsion of the optic nerve]. Rev Chir Oncol Radiol O R L Oftalmol Stomatol Ser Oftalmol 1982; 26:209-11. [PMID: 6218536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
|
15
|
Hirizescu D, Hirizescu E, Iordache V, Berculescu Z. [Contrast radiography in the diagnosis of maxillary sinusitis]. Otorinolaringologie 1973; 18:27-36. [PMID: 4144207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
|
16
|
Hirizescu E, Hirizescu D, Vajda F, Iordache V. [Facial sinus fibroma]. Otorinolaringologie 1971; 16:43-54. [PMID: 5553217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
|