Pneumothorax Side Research Articles

Outcomes of Non-intubated Versus Intubated Thoracoscopic Surgery for Primary Spontaneous Pneumothorax.

This study aimed to compare the outcomes of non-intubated video-assisted thoracic surgery (N-VATS) and intubated video-assisted thoracic surgery (I-VATS) for primary spontaneous pneumothorax (PSP). We retrospectively analyzed 120 consecutive patients who underwent VATS for PSP. The patients were divided into N-VATS and I-VATS groups. Demographics, clinical characteristics, postoperative results, pain scores, follow-up results, and management were evaluated and compared between the groups. Local anesthesia and deep sedation (ketamine 2mg/kg IV and propofol 2mg/kg IV slow infusion) were administered under spontaneous ventilation in the N-VATS group. The groups did not differ significantly in terms of age, sex, American Society of Anesthesiology score, pneumothorax side, or smoking history ( P >0.05). The mean operation time, anesthesia time, oral intake opening time, and mobilization time were significantly shorter in the N-VATS group (26.04±4.61 vs. 48.26±7.82min, 42.14±6.40 vs. 98.16±12.4min, 2.1±0.4 vs. 8.4±1.2h, and 4.2±0.9 vs. 2.6±1.4 between N-VATS and I-VATS, respectively; P <0.05). The surgical outcomes did not differ in terms of minor complications (12%-13%) and recurrence rates (5.1%-6.4%) during a mean follow-up period of 88.4±10.2mo. No cases of conversion to open surgery or mortality were observed. General anesthesia and intubation were not required for any patient in the N-VATS group. Our results revealed no differences in minor complications or recurrence rates between groups. However, the N-VATS group had significantly shorter operation, anesthesia, oral intake opening, and mobilization times. The most important advantage of N-VATS for PSP is its fast recovery while avoiding the risks of general anesthesia and intubation. Further prospective studies with larger sample sizes are warranted.

A different approach in primary spontaneous pneumothorax surgery: Lateral pleurectomy technique and results

Background: Primary Spontaneous Pneumothorax is a disease with a frequent recurrence rate. The uniportal videothoracoscopic surgery approach is the standard treatment for air leak and recurrence prevention. In common practice, apical pleurectomy is used after apical wedge resection. Our study aims to examine the results, especially the recurrence rate, of the lateral pleurectomy and apical pleural abrasion combination technique applied as an alternative to this technique.Methods: A total of 50 patients who underwent uniportal videothoracoscopic surgery for primary spontaneous pneumothorax between November 2018 and May 2021 were included in the study. The follow-up period for recurrence of the patients was 12-42 months. Age, gender, pneumothorax side, operation indication, Body Mass Index, smoking history, incision length and location, air leakage and tube thoracostomy duration, Verbal Numeric Pain Scores, post-operative length of hospital stay, complications, and recurrence data were recorded.Results: Of the 50 patients, 44 (88%) were male, and 6 (12%) were female, with a mean age of 22.3±5.9 years. Surgery was performed from the existing drain site in 32 (64%) cases and the former drain scar in 11 (22%) cases. The mean duration of tube thoracostomy was 2.7±0.97 days, and the mean length of hospital stay was 3.6±0.89 days. Complications developed in 2 (4%) cases, and recurrence was observed in 2 (4%) cases.Conclusions: Lateral pleurectomy with the apical pleural abrasion technique is easy to apply and reduces the possibility of undesired hemorrhagic drainage. We believe that the lateral pleurectomy technique is safe, easily applicable, and less risky in terms of hemorrhage.

Risk Factors and Outcome of Pneumothorax in Neonates at Benghazi Children Hospital during Three Years Review

Background: Pneumothorax occurs more frequently in the neonatal period than in any other period of life and it is associated with the increased mortality and morbidity. Aims: This study was conducted to evaluate the frequency of pneumothorax and to assess risk factors, management as well as the outcome of newborn infants with pneumothorax. Subjects and Methods: A case series study of 112 newborns infants with pneumothorax (PTX) who were admitted and treated at NICU in Benghazi children hospital in Libya for three years period, from January 2018 to December 2020 are included in this descriptive study. Medical records were evaluated for baseline characteristics of neonates, predisposing factors of neonatal PTX, management and mortality. Results: During the observed three-year period, 5166 neonates were admitted to hospital and 112 of neonates were diagnosed with pneumothorax (CXR confirmed), so the frequency of pneumothorax was 2.2% from neonatal admission. Males outnumbered females by a ratio of 1.9:1. Full term delivery was recorded in 60.7% of patients and 39.3% were pre term. Mean birth weight was 2.5±0.67 kg, with medium weight 2.8kg and minimum weight was 1.08kg and maximum weight was 4.5kg. More than half (68.7%) of patients had birth weight ≥2.5kg. Administration of corticosteroid during pregnancy was recorded in 13.4% of mothers. Concerning mode of delivery, C/S constitute 75%, elective C/S was recorded in 64.3% and 35.7% was emergency, while normal delivery recorded 25%. Spontaneous pneumothorax was found in 32.1%, and secondary pneumothorax was recorded in 67.9% of patients. Age of baby when had PTX was ≤ 48 hours of age in 63.4% of them and &gt;48 hours of age in 36.6%. Side of PTX was at right side in 54.5%, at left side in 22.3% and bilateral in 23.2%. Underlying lung pathology was recorded in 60.7% of patients, 41% had hyaline membrane disease, 8.9% had transient tachypnea of newborn, 6.3% had Congenital Pneumonia, 2.7% had Meconium aspiration ............

THE EFFECT OF COVID-19 VACCINES ON PNEUMOTHORAX IN GERIATRIC PATIENTS HOSPİTALIZED IN INTENSIVE CARE UNIT DUE TO COVID-19.

In our study, we examined the effect of COVID-19 vaccination on the incidence of pneumothorax in intensive care patients over age 65. COVID-19 intensive care patients that presented to our department between April 2020 and May 2021 during the COVID-19 pandemic were evaluated retrospectively. Patients were divided into two main groups, i.e., before and after the vaccination period. Patients were evaluated retrospectively for the following parameters: gender, age, side of pneumothorax, mortality, discharge, comorbidity, and additional pleural complications. The total number of patients was 87, i.e., 66 patients before vaccination and 21 patients after vaccination. When patients in the pre- and post-vaccination period were compared, there was a significant difference in the incidence of pneumothorax between the two groups (p<0.05). Pneumothorax was less common after vaccination. When patients with pneumothorax and tube thoracostomy were evaluated according to pre- and post-vaccination mortality, mortality was significantly higher (89%) in the pre-vaccination period (p<0.05). We consider that COVID-19 vaccines used in patients aged over 65 reduced the incidence of pleural complications, especially pneumothorax. We think that mortality due to pneumothorax in patients over 65 years of age was lower during the vaccination period. In addition, we think that bilateral pneumothorax was more common in the non-vaccinated period. As a result, we think that life-threatening pneumothorax and similar complications could be reduced by increasing the number of vaccines made in the COVID-19 pandemic and spreading it around the world.

Two-port versus three-port video-assisted thoracoscopic surgery for primary spontaneous pneumothorax: feasibility, postoperative outcome and long-term recurrence rates

BackgroundTwo-port VATS (2-P-VATS) and three-port VATS (3-P-VATS) are well-established techniques for surgical therapy of primary spontaneous pneumothorax (PSP). However, comparisons of both techniques in terms of postoperative outcome and recurrence are limited.MethodsFrom January 2010 to March 2020, we retrospectively reviewed data of 58 PSP patients who underwent VATS in our institution. For statistical analysis, categorical and continuous variables were compared by chi-square test or Fisher’s exact test and the Student´s t-test, respectively. Twenty-eight patients underwent 2-P-VATS and 30 were treated with 3-P-VATS. Operation time, length of hospital stay (LOS), total dose of analgesics per stay (opioids and non-opioids), duration of chest tube drainage, pleurectomy volume (PV), postoperative complications and recurrence rates were compared between both groups.ResultsClinical and surgical characteristics including mean age, gender, Body-Mass-Index (BMI), pneumothorax size, smoking behaviour, history of contralateral pneumothorax, side of pneumothorax, pleurectomy volume and number of resected segments were similar in both groups. The mean operation time, LOS and total postoperative opioid and non-opioid dose was significantly higher in the 3-P-VATS group compared with the 2-P-VATS group. Despite not being statistically significant, duration of chest tube was longer in the 3-P-VATS group compared with the 2-P-VATS group. In terms of postoperative complications, the occurrence of hemothorax was significantly higher in the 3-P-VATS group (3-P-VATS vs. 2-P-VATS; p = 0.001). During a median follow-up period of 61.6 months, there was no significant statistical difference in recurrence rates in both groups (2/28 (16.7%) vs. 5/30 (7.1%); p = 0.274).ConclusionOur data demonstrate that 2-P-VATS is safer and effective. It is associated with reduced length of hospital stay and decreased postoperative pain resulting in less analgesic use.

Quantification analysis of pleural line movement for the diagnosis of pneumothorax.

BACKGROUNDThere is no research on quantitative pleural line movement. In this study, we assume that tissue Doppler and its quantitative technology can quantify the pleural line movement and can be used to diagnose pneumothorax.AIMTo evaluate the quantitative assessment of pleural line movement measured by tissue Doppler imaging (TDI) for pneumothorax diagnosis.METHODSAdult patients (n = 45) diagnosed with unilateral pneumothorax were included in this study. Each patient underwent TDI of both lungs. The pneumothorax side and contralateral normal lung side were compared using several indices obtained from TDI: peak pleural line velocity (PVmax), peak chest wall tissue velocity (CVmax), peak pleural line strain value (PSmax), peak chest wall tissue strain value (CSmax), PVmax/CVmax and PSmax/CSmax. The receiver operating characteristic analysis was used to evaluate the performance of these quantitative assessments for pneumothorax diagnosis.RESULTSVarious quantitative variables of the pneumothorax side were all lower than that of the non-pneumothorax side and included the PVmax (0.36 cm/s vs 0.59 cm/s, P < 0.001), PSmax (1.14% vs 1.90%, P = 0.001), PVmax/CVmax (1.06 vs 4.93, P < 0.001), and PSmax/CSmax (0.76 vs 1.74, P < 0.001). For the discrimination of pneumothorax, the cut-off values of the PVmax, PSmax, PVmax/CVmax, and PSmax/CSmax were calculated as 0.50 cm/s, 0.94%, 1.96, and 1.12, respectively. Similarly, the sensitivities and specificities of PVmax, PSmax, PVmax/CVmax, and PSmax/CSmax were 96% and 62%, 47% and 91%, 93% and 96%, and 82% and 93%, respectively. The area under the receiver operating characteristic curve were 0.84, 0.72, 0.99, and 0.91, respectively, for PVmax, PSmax, PVmax/CVmax, and PSmax/CSmax.CONCLUSIONQuantification analysis of pleural line movement using TDI is a useful tool for the diagnosis of pneumothorax.

Spontaneous pneumothorax as a complication of lung injury due to COVID-19

The objective of the study: to study the course and clinical outcomes of spontaneous pneumothorax (SP) in patients with lung injury due to COVID-19.Subjects and methods. Clinical and radiation data of 11 patients (above 18 years old) with SP due to COVID-19 were retrospectively analyzed, they all were treated in the thoracic surgery department. COVID-19 was confirmed in all patients by laboratory tests. According to the chest computed tomography, the patients had signs typical of viral pneumonia and SP.Results. The surgical treatment of SP that included thoracocentesis on the pneumothorax side and closed drainage of the pleural cavity allowed resolving the pneumothorax and inflating the lung fully in 10/11 patients within 4 days on average (max = 7 days) from the moment when the surgery was done. The lethal outcome was in 1/11 (9.1%) patient which occurred 1 day after the diagnosis and successful drainage of the bilateral SP, the patient had symptoms of acute cardiovascular failure.

Minimally invasive approach to pneumothorax: Single port or two ports?

This study aims to compare the effectiveness of single-port and two-port video-assisted thoracoscopic surgery in patients with pneumothorax. Between June 2016 and December 2018, a total of 44 patients (39 males, 5 females; mean age 27.0±9.5 years; range, 15 to 60 years) who underwent video-assisted thoracoscopic surgery due to the spontaneous pneumothorax in our center were retrospectively evaluated. The study population was divided into two groups as the single-port (n=29) and two-port (n=15) procedure according to the number of port entries applied during the operation. Age, gender, number of days of drainage, length of hospitalization, number of days of air leak, the indication of operation, pneumothorax side, type of pneumothorax, duration of operation, and complications were compared between the groups. Twenty-two patients (50%) were operated on the right side and 22 patients (50%) on the left side. The mean operation time was 81.1±19.2 min, indicating no significant difference between the groups (p=0.053). No significant difference was observed in the number of days of drainage, the length of hospitalization, and number of days of air leak between the two groups. Complications developed in eight patients (27.6%) in the single-port group and five patients (33.3%) in the two-port group, indicating no significant difference between the groups (p=0.475). Our study results show that video-assisted thoracoscopic surgery for the treatment of pneumothorax can be successfully performed via a single-port approach.

Speckle tracking quantification of lung sliding for the diagnosis of pneumothorax: a multicentric observational study.

Lung ultrasound is used for the diagnosis of pneumothorax, based on lung sliding abolition which is a qualitative and operator-dependent assessment. Speckle tracking allows the quantification of structure deformation over time by analysing acoustic markers. We aimed to test the ability of speckle tracking technology to quantify lung sliding in a selected cohort of patients and to observe how the technology may help the process of pneumothorax diagnosis. We performed retrospectively a pleural speckle tracking analysis on ultrasound loops from patients with pneumothorax. We compared the values measured by two observers from pneumothorax side with contralateral normal lung side. The receiver operating characteristic (ROC) curve was constructed to evaluate the performance of maximal pleural strain to detect the lung sliding abolition. Diagnosis performance and time to diagnosis between B-Mode and speckle tracking technology were compared from a third blinded observer. We analysed 104 ultrasound loops from 52 patients. The area under the ROC curve of the maximal pleural strain value to identify lung sliding abolition was 1.00 [95%CI 1.00; 1.00]. Specificity was 100% [95%CI 93%; 100%] and sensitivity was 100% [95%CI 93%; 100%] with the best cut-off of 4%. Over 104 ultrasound loops, the blinded observer made two errors with B-Mode and none with speckle tracking. The median diagnosis time was 3 [2-5] seconds for B-Mode versus 2 [1-2] seconds for speckle tracking (p = 0.001). Speckle tracking technology allows lung sliding quantification and detection of lung sliding abolition in case of pneumothorax on selected ultrasound loops.

A novel structural risk index for primary spontaneous pneumothorax: Ankara Numune Risk Index

In this study, we aimed to reveal a novel risk index as a structural risk marker for primary spontanoeus pneumothorax using body mass index and chest height, structural risk factors for pneumothorax development. Records of 86 cases admitted between February 2014 and January 2015 with or without primary spontaneous pneumothorax were analysed retrospectively. The patients were allocated to two groups as Group I and Group II. The patients were evaluated with regard to age, gender, pneumothorax side, duration of hospital stay, treatment type, recurrence, chest height and transverse diameter on posteroanterior chest graphy and body mass index. Body mass index ratio per cm of chest height was calculated by dividing body mass index with chest height. We named this risk index ratio which is defined first as 'Ankara Numune Risk Index'. Diagnostic value of Ankara Numune Risk Index value for prediction of primary spontaneous pneumothorax development was analysed with Receiver Operating Characteristics curver. Of 86 patients, 69 (80.2%) were male and 17 (19.8%) were female. Each group was composed of 43 (50%) patients. When Receiver Operating Characteristics curve analysis was done for optimal limit value 0.74 of Ankara Numune Risk Index determined for prediction of pneumothorax development risk, area under the curve was 0.925 (95% Cl, 0.872-0.977, p<0.001). Ankara Numune Risk Index is one of the structural risk factors for prediction of primary spontaneous pneumothorax development however it is insufficient for determining recurrence.

Pneumothorax size measurements on digital chest radiographs: Intra- and inter- rater reliability

Detailed and reliable methods may be important for discussions on the importance of pneumothorax size in clinical decision-making. Rhea's method is widely used to estimate pneumothorax size in percent based on chest X-rays (CXRs) from three measure points. Choi's addendum is used for anterioposterior projections. The aim of this study was to examine the intrarater and interrater reliability of the Rhea and Choi method using digital CXR in the ward based PACS monitors. Three physicians examined a retrospective series of 80 digital CXRs showing pneumothorax, using Rhea and Choi's method, then repeated in a random order two weeks later. We used the analysis of variance technique by Eliasziw et al. to assess the intrarater and interrater reliability in altogether 480 estimations of pneumothorax size. Estimated pneumothorax sizes ranged between 5% and 100%. The intrarater reliability coefficient was 0.98 (95% one-sided lower-limit confidence interval C 0.96), and the interrater reliability coefficient was 0.95 (95% one-sided lower-limit confidence interval 0.93). This study has shown that the Rhea and Choi method for calculating pneumothorax size has high intrarater and interrater reliability. These results are valid across gender, side of pneumothorax and whether the patient is diagnosed with primary or secondary pneumothorax.

Retrospective Analysis of Hospitalized Neonates İn A Neonatal İntensive Care Unit Diagnosed As Pneumothorax

Aim: Pneumothorax is one of the important etiologic factors in newborns that causes respiratory distress. Pneumothorax usually occurs in newborns under mechanical ventilation. Respiratory distress syndrome, meconium aspiration syndrome and resuscitation after birth may also cause pneumothorax. In this study, we retrospectively analyzed newborn who were hospitalized for pneumothorax in our newborn intensive care unit. Material and Methods: We retrospectively analyzed 56 cases who were hospitalized for pneumothorax in our newborn intensive care unit between 2008-2011. These cases were evaluated according to demographic characteristics, diagnosis, treatment, duration the hospitalization and prognosis. The diagnosis was made by chest x-rays. Cases were treated with chest tube drainage. For statistical analysis, Pearson Chi Square test and Fisher's Exact test were used and p <0.05 was considered statistically significant. Results: Frequency of pneumothorax was higher in males and term infants. Additionally unilateral pneumothorax and left side was seen more often. Respiratory distress syndrome was found to be the most common primary lung disease. Perinatal asphyxia was the most common coexisting disease. In our study; pneumothorax developed in 21 patients during mec­hanical ventilation support. The mortality rate was 48,2%. There was a significant relationship between mortality and the side of pneumothorax, accompanying disorders, need for surfactant, resuscitation and development of pneumothorax under mechanical ventilation (p<0,05). Conclusion: Pneumothorax is a life-threatening condition with high mortality and morbidity. We found that the mortality rate was higher in patients who developed pneumothorax under mechanical ventilation, needed surfactant, was resuscitated during delivery, who had bilateral pneumothorax and accompanying disorders. Key Words: Pneumothorax; Newborn; Intensive Care Unit; Mortality.

Transient decrease in PaCO2 and asymmetric chest wall dynamics in early progressing pneumothorax

Diagnosis of pneumothorax (PTX) in newborn infants has been reported as late. To explore diagnostic indices for early detection of progressing PTX, and offer explanations for delayed diagnoses. Progressing PTX was created in rabbits (2.3 ± 0.5 kg, n = 7) by injecting 1 ml/min of air into the pleural space. Hemodynamic parameters, tidal volume, EtCO(2), SpO(2), blood gas analyses and chest wall tidal displacements (TDi) on both sides of the chest were recorded. (Mean ± SD): A decrease in SpO(2) below 90 % was detected only after 46.6 ± 11.3 min in six experiments. In contrary to the expected gradual increase of CO(2), there was a prolonged transient decrease of 14.2 ± 4.5 % in EtCO(2) (p < 0.01), and a similar decrease in PaCO(2) (p < 0.025). EtCO(2) returned back to baseline only after 55.2 ± 24.7 min, and continued to rise thereafter. The decrease in CO(2) was a mirror image of the 14.6 ± 5.3 % increase in tidal volume. The analysis of endotracheal flow and pressure dynamics revealed a paradoxical transient increase in the apparent compliance. Significant decrease in mean arterial blood pressure was observed after 46.2 ± 40.1 min. TDi provided the most sensitive and earliest sign of PTX, decreasing on the PTX side after 16.1 ± 7.2 min. The TDi progressively decreased faster and lower on the PTX side, thus enabling detection of asymmetric ventilation. The counterintuitive transient prolonged decrease in CO(2) without changes in SpO(2) may explain the delay in diagnosis of PTX encountered in the clinical environment. An earlier indication of asymmetrically decreased ventilation on the affected side was achieved by monitoring the TDi.

Pleural abrasion versus pleurectomy in primary spontaneous pneumothorax surgery

Background: In this study, we aimed to compare the success of pleural adhesion procedures (pleural abrasion versus a pleurectomy) in preventing recurrence after the surgical treatment of primary spontaneous pneumothorax (PSP). Methods: Between January 2006 and December 2008, the results of 208 operations performed on 190 patients with PSP were examined. As pleural adhesion procedures, 87 pleural abrasions (group A) [20 via video-assisted thoracic surgery (VATS); 67 via axillary thoracotomy (AT)] and 121 apical parietal pleurectomies (group P) (34 via VATS; 87 via AT) were performed. The patients in groups A and P were followed up for a median of 46 (range 28-63) and 41 (range 28-63) months, respectively. They were monitored for recurrence, and, if present, the factors affecting the recurrence were then analyzed. Results: No differences between the groups were found with respect to age, pneumothorax side, surgical indications, surgical approach, duration of surgery, or complication development. The chest tube duration and hospitalization time were significantly shorter in group P (p=0.0001 and p=0.002, respectively). Recurrence developed in six patients (6.8%) in group A and one patient (0.8%) in group P (p=0.02). In the univariate analysis, no relationship was found between the rate of recurrence and the surgical approach, age, gender, pneumothorax side, or surgical indication. In the logistic regression analysis, the surgical approach and pleural adhesion procedure were independent predictors of recurrence (p=0.048 and p=0.034, respectively). Conclusion: A pleurectomy is more effective than abrasion at preventing postoperative recurrence in PSP surgery. Additionally, it has advantages in terms of chest tube duration and hospitalization time.

The results of wedge resection and partial pleurectomy in the surgical treatment of primary spontaneous pneumothorax: videothoracoscopy or axillary thoracotomy?

Background: In this study we compared the results of wedge resection and partial pleurectomy in primary spontaneous pneumothorax (PSP) patients treated using video-assisted thoracoscopic surgery (VATS) and axillary thoracotomy approaches. Methods: Four-hundred and seventy-eight patients were treated in our clinic for PSP between January 2007 and December 2008. We performed 110 apical wedge resections with a stapler and a partial pleurectomy in 101 patients. Fortyfive of the procedures were performed with VATS (group V) and 65 with axillary thoracotomy (group T) approaches. The two groups were compared with respect to the duration of the procedure, number of stapler reload units used, duration of chest tube, requirement for postoperative narcotic analgesics, postoperative complications, need for reoperation, and recurrence rate. Student's t-test, the chi-square test, and Fisher's exact test were used for the statistical analysis. Results: There were no significant differences between groups V and T in terms of age, gender, smoking habits, pneumothorax side, surgical indications, duration of surgery, postoperative duration of chest tube, postoperative complication rate, reoperation rate, or recurrence rate. Narcotic analgesics were needed in five cases in group V and 20 cases in group T (p=0.02). The mean number of stapler reload units used during the operation was 2.7 in group V and 1.43 in group T (p

Primary spontaneous pneumothorax: 1-year recurrence rate after simple aspiration

Recurrence rate is an important factor to consider when choosing the modality of treatment for primary spontaneous pneumothorax. The recurrence rate after simple aspiration has only been previously reported in several relatively small studies. The objectives of this study was to investigate the 1-year recurrence rate of primary spontaneous pneumothorax after treatment by simple aspiration and the potential risk factors for recurrence. A retrospective cohort study was performed over a 2-year period on 91 consecutive patients with primary spontaneous pneumothorax who were treated with simple aspiration. The setting was an emergency department of a 1400-bed university teaching hospital in Hong Kong. Recurrence within 1 year and associated risk factors were assessed by telephone follow-up interviews. The factors evaluated were age, sex, side of pneumothorax, previous and present smoking history, history of previous pneumothorax, size of pneumothorax at initial assessment, volume of air aspirated, and final outcome. The overall 1-year recurrence rate was 15.7% [95% confidence interval (CI), 8.9-25.0%]. The recurrence rate for patients who had successful simple aspiration was 17.6% (95% CI, 8.0-32.1%). In patients who had successful aspiration, the median size of pneumothorax at initial presentation for those with recurrence was 17.5% (95% CI, 12.0-23.0%), compared with 25.0% (95% CI, 22.7-30.6%) for those without recurrence (P = 0.044). The 1-year recurrence rate after successful simple aspiration for primary spontaneous pneumothorax in Chinese patients in Hong Kong is not high. Recurrence within 1 year appears to be associated with smaller initial size of pneumothorax.

SPONTANEOUS PNEUMOTHORAX

We asked three questions: whether (i) spontaneous pneumothorax (SP) size could be measured volumetrically on conventional posteroanterior (PA) and lateral (LAT) chest radiographs; (ii) radiologists could accurately estimate pneumothorax volume using qualitative criteria, and: (iii) a simple formula could be derived which would allow accurate estimation of SP volume using two or three measurements taker from PA and LAT chest films. We reasoned that the volume of lung and hemithorax on the pneumothorax side could be measured on PA and LAT films with a modification of the computerized method (Barrett et al: AARD 1976; 113:239–244) of Barnhard (Am J Med 1970; 28:51–60) Pneumothorax volume is the difference between these volumes expressed as a percent PA and LAT chest films on 17 otherwise healthy men, mean age 26 years, with uncomplicated SP were measured using this technique. Then, each of 6 radiologists reviewed the 17 film pairs and was asked to “estimate the size of pneumothorax as a percent”. Subsequently, linear dimensions of height (H) width (W), and depth (D) of the hemithorax and lung were measured on PA and LAT films to develop a simple formula relating the volume of pneumothorax to the change in linear proportions. Pneumothorax occurred on right and left with equal incidence and volumes measured from 4% to 74% with a mean of 28%. Defining “agreement” as within ± 12, radialogists' estimates of pneumothorax size agreed with measured volumes only 50% of the time, with error ranging 0 to 61 percentage points. Radiologists' estimates agree with each other in any single case approximately 50% of the time. Agreement occurred most frequently when measured volume was 10% to 40%. The ratio of the volumes of lung, before and after pneumothorax, is equal to the cube of the fractional decreases in H, W and D. This theoretical concept has been experimentally confirmed by Axel (A simple way to estimate the size of a pneumothorax. Invest. Radiol 1981; in press). Pneumothorax volume prediction in this study from the fractional decreases in H and W (with or without D) shows good agreement with volumetric estimates. Thus, an accurate estimate of pneumothorax volume can be easily calculated from ΔH and ΔW measured on PA chest films.