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PubMed1998

[Patients with acute respiratory distress syndrome mechanically ventilated in prone position].

Animal experiments and human studies have shown better oxygenation in mechanically ventilated patients with ARDS when the patient is situated in the prone position. In contradiction to former theories of a gravitational gradient of lung perfusion, a number of investigators have found that lung perfusion is preferentially distributed to the dorsal lung regions regardless of body position. The basal atelectasis and oedema in ARDS are resolved and only partly distributed anteriorly in the prone position, and these areas are thereby better ventilated. The combination of better ventilation and unchanged perfusion improves the ventilation/perfusion ratio and decreases the shunt in the prone position. In two cases of prone position in mechanically ventilated patients the PaO2/FiO2 ratio increased from 7.5 to 14.3 and from 8.8 to 19.8 after one hour in the prone position, and some of the improvement was permanent. Prone position has only minor side effects and is recommended as the first choice amongst adjunct therapies in mechanical ventilation in patients with ARDS remaining hypoxic in conventional therapy in the supine position.

Acute Disease↗

PubMed2000

Angiotensin II formation and endothelin clearance in ARDS patients in supine and prone positions.

OBJECTIVE: In patients with acute respiratory distress syndrome (ARDS), the prone position may enhance oxygenation by changing ventilation/perfusion ratio. In this study, we investigated whether the prone position affects the net balance between pulmonary endothelin (ET-1) and angiotensin II (Ang II) production and clearance, two metabolic functions of lung endothelial cells. SETTING: Anaesthesiological intensive care unit of a university hospital. PATIENTS: Ten ARDS patients (Murray score > 2.5) were studied in both the supine position (SP) and the prone position (PP). MEASUREMENTS AND DESIGN: Blood samples were taken simultaneously from the patient in SP for assessment of mixed venous and arterial ET-1 and Ang II concentrations, and plasma renin concentration (PRC). This was repeated after 60 min in SP, immediately after turning the patient into PP, and 60 min thereafter. Net arterial/mixed venous ET-1 clearances and net Ang II formations were calculated. RESULTS: arterial oxygen tension increased from SP to PP by an average of 60 mmHg, about 20%. Arterial ET-1 concentrations of ARDS patients were 1.57 +/- 1.1 pg/ml (mean +/- SD) and within the range of healthy persons. Net ET-1 clearances were negative in SP, indicating pulmonary release of ET-1, and did not change in PP. Arterial Ang II concentrations (73 +/- 56 pg/ml) as well as PRC (126 +/- 85 pg/ml) were markedly elevated. Net transpulmonary Ang II formation did not change. CONCLUSION: Acute changes of oxygenation in ARDS patients by positioning do not induce any short-term effects on pulmonary ET-1 net clearance or Ang II net formation.

Adult↗

PubMed2003

Does prone positioning reduce small bowel dose in pelvic radiation with intensity-modulated radiotherapy for gynecologic cancer?

PURPOSE: Intensity-modulated radiotherapy (IMRT) has been shown to reduce the radiation dose to small bowel in pelvic RT in gynecology patients. Prone positioning has also been used to decrease small bowel dose by displacement of small bowel from the RT field in these patients. The purpose of this study was to determine whether the combination of both IMRT and prone positioning on a belly board can reduce small bowel dose further in gynecologic cancer patients undergoing pelvic RT. METHODS AND MATERIALS: IMRT plans for pelvic RT were computed in 16 patients with gynecologic cancer who had undergone planning CT scans in both the supine and the prone positions on a belly board. For the gross tumor volume, the uterus, cervix, and tumor (or postoperative region) were traced. The clinical target volume was defined as the vessels and lymph nodes from the obturator level to the aortic bifurcation, presacral region, and upper 4 cm of the vagina, in addition to gross tumor volume. The planning target volume was defined as a 2-cm margin in addition to the gross tumor volume and upper 4 cm of the vagina, and 1.5 cm for lymph nodes and vessels. Normal tissue regions of interest included small bowel, large bowel, and bladder. IMRT plans using (1) the limited arc technique (180 degrees arc length) and (2) the extended arc technique (340 degrees arc length) were computed. Dose-volume histograms for normal tissue structures and target were compared between the supine and prone IMRT plans using the paired t test. RESULTS: Prone positioning on a belly board decreased the small bowel dose in gynecologic pelvic IMRT, and the magnitude of improvement depended on the specific IMRT technique used. With the limited arc technique, prone positioning significantly decreased the irradiated small bowel volume at the 25-50-Gy dose levels compared with supine positioning. Small bowel volumes receiving > or =45 Gy decreased from 19% to 12.5% (p = 0.005) with prone positioning. With the extended arc technique, the decrease in irradiated small bowel volume was less marked, but remained detectable in the 35-45-Gy dose levels. Small bowel volumes receiving > or =45 Gy decreased from 13.6% to 10.1% (p = 0.03) with prone positioning. The effect of prone positioning on large bowel and bladder was variable. Large bowel volumes receiving > or =45 Gy increased with prone positioning from 16.5% to 20.6% (p = 0.02) in the limited arc technique and was unaffected in the extended arc technique. CONCLUSION: These preliminary data suggest that prone positioning on a belly board can reduce the small bowel dose further in gynecology patients treated with pelvic RT, and that the dose reduction depends on the IMRT technique used.

Adult↗

PubMed2005

Effect of prone positioning on clinical outcomes in children with acute lung injury: a randomized controlled trial.

CONTEXT: In uncontrolled clinical studies, prone positioning appeared to be safe and to improve oxygenation in pediatric patients with acute lung injury. However, the effect of prone positioning on clinical outcomes in children is not known. OBJECTIVE: To test the hypothesis that at the end of 28 days infants and children with acute lung injury treated with prone positioning would have more ventilator-free days than those treated with supine positioning. DESIGN, SETTING, AND PATIENTS: Multicenter, randomized, controlled clinical trial conducted from August 28, 2001, to April 23, 2004, of 102 pediatric patients from 7 US pediatric intensive care units aged 2 weeks to 18 years who were treated with supine vs prone positioning. Randomization was concealed and group assignment was not blinded. INTERVENTION: Patients were randomized to either supine or prone positioning within 48 hours of meeting acute lung injury criteria, with those patients in the prone group being positioned within 4 hours of randomization and remaining prone for 20 hours each day during the acute phase of their illness for a maximum of 7 days, after which they were positioned supine. Both groups were treated using lung protective ventilator and sedation protocols, extubation readiness testing, and hemodynamic, nutrition, and skin care guidelines. MAIN OUTCOME MEASURE: Ventilator-free days to day 28. RESULTS: The trial was stopped at the planned interim analysis on the basis of the prespecified futility stopping rule. There were no differences in the number of ventilator-free days between the 2 groups (mean [SD], 15.8 [8.5] supine vs 15.6 [8.6] prone; mean difference, -0.2 days; 95% CI, -3.6 to 3.2; P = .91). After controlling for age, Pediatric Risk of Mortality III score, direct vs indirect acute lung injury, and mode of mechanical ventilation at enrollment, the adjusted difference in ventilator-free days was 0.3 days (95% CI, -3.0 to 3.5; P = .87). There were no differences in the secondary end points, including proportion alive and ventilator-free on day 28 (P = .45), mortality from all causes (P>.99), the time to recovery of lung injury (P = .78), organ-failure-free days (P = .88), and cognitive impairment (P = .16) or overall functional health (P = .12) at hospital discharge or on day 28. CONCLUSION: Prone positioning does not significantly reduce ventilator-free days or improve other clinical outcomes in pediatric patients with acute lung injury.

Adolescent↗

PubMed2002

Prone position increases collapsibility of the passive pharynx in infants and small children.

On the basis of two observations that avoiding prone sleeping decreased incidence of sudden infant death syndrome and that obstructive sleep apnea is closely linked with the syndrome, we hypothesized that the prone position may increase upper airway collapsibility in infants and small children. Passive pharyngeal collapsibility of 19 infants and small children (10-101 weeks old) was examined in three postures: supine with face straight up, supine with neck rotated, and prone with neck rotated. The collapsibility was evaluated with the maximal distension of the most collapsible region, pharyngeal stiffness, and pharyngeal closing pressure, estimated from static pressure-area relationship of the passive pharynx. No significant changes in pharyngeal stiffness were detected; however, maximal distension was reduced in the prone position (mean +/- SD, 0.56 +/- 0.26 versus 0.44 +/- 0.20 cm(2); supine with face straight up versus prone position, p < 0.05). Pharyngeal closing pressure increased at neck rotation in the supine position (-4.5 +/- 2.4 versus -2.8 +/- 2.3 cm H(2)O; supine with face straight up versus supine with neck rotated, p < 0.05), and a further increase was observed in the prone position (-0.3 +/- 2.9 cm H(2)O, p < 0.05 versus supine with neck rotation). Pharyngeal closing pressure in the prone position was above atmospheric pressure in half of our subjects, whereas all subjects had negative pharyngeal pressure in the supine position. We conclude that the prone position increases upper airway collapsibility, although the mechanism is yet unclear.

Airway Resistance↗

PubMed1991

Improved oxygenation with prone positioning in neonates: stability of increased transcutaneous PO2.

To evaluate the effect of body position on oxygenation and ventilation in neonates over a prolonged period, infants with respiratory disease were followed by transcutaneous (tc) monitoring for alterations in tcPO2 and tcPCO2 with position changes. In 14 studies of seven patients, prone positioning was compared with supine positioning over a 6-hour interval. All patients were premature, were receiving supplemental oxygen, and had respiratory disease secondary to prematurity. The median gestational age was 29 weeks; all infants were 2 months old or less at the time of the study. Prone positioning resulted in a significantly higher tcPO2; mean (+/- SD) tcPO2 increased from 63 (+/- 11.6) mm Hg to 71 (+/- 14.6) mm Hg, and decreased to 65 (+/- 11.2) mm Hg when the infant was returned to supine (P less than .05). This increase in tcPO2 was stable throughout 2 hours in the prone position. No significant change in tcPCO2 was detected. Infants were also found to spend a greater proportion of time sleeping when prone (75% +/- 13% vs 33% +/- 14%; P less than .05). These finding suggest that improvement in oxygenation with the prone position is stable over an extended period in the sick preterm infant.

Blood Gas Monitoring, Transcutaneous↗

PubMed2003

Prone positioning in acute respiratory distress syndrome.

The ultimate efficacy of prone positioning in ARDS is difficult to evaluate because of heterogeneous study populations, the variances in the duration of the prone position, and the small sample sizes used in most studies. Prone positioning offers an easy, readily available treatment option for refractory hypoxemia. Although there is a rationale supporting the hypothesis that prone ventilation could reduce the mortality of ARDS patients, currently there are insufficient clinical data to support this hypothesis.

Humans↗

PubMed2002

Effect of prone position on hepato-splanchnic hemodynamics in acute lung injury.

OBJECTIVE: To evaluate the effects of prone position on hepato-splanchnic hemodynamics, metabolism and gut mucosal energy balance. DESIGN: Prospective clinical study. SETTING: Medical intensive care unit in a university hospital. PATIENTS: Eleven hemodynamically stable patients with acute lung injury (ALI) requiring mechanical ventilation. INTERVENTION: Patients were studied in the supine position, after 90 min in the prone position and after 90 min of supine repositioning. MEASUREMENTS AND RESULTS: In addition to global hemodynamics we measured intra-abdominal pressure (IAP, bladder), hepato-splanchnic blood flow (HSBF, steady state indocyanine green technique using a hepatic vein catheter) and gastric mucosal-arterial PCO(2) gap (PCO(2) gap, automated air tonometry). Systemic hemodynamics did not change during the whole study. Prone positioning did not significantly affect IAP. HSBF as well as splanchnic oxygen consumption remained unaltered, too. Similarly, neither liver lactate uptake nor indocyanine green extraction were influenced by positional changes. Finally, stable regional hemodynamics were accompanied by an unchanged PCO(2) gap. CONCLUSION: We conclude that if IAP and systemic hemodynamics remain unaffected, the prone position in ALI patients compromises neither hepato-splanchnic perfusion nor gastric mucosal energy balance.

Acute Disease↗

PubMed1999

Respiratory and haemodynamic effects of the prone position at two different levels of PEEP in a canine acute lung injury model.

This study was designed to examine whether the oxygenation response in the prone position differs in magnitude depending on the level of positive end-expiratory pressure (PEEP) applied in the supine position, and whether cardiac output (CO) increases in the prone position. In seven supine dogs, acute lung injury was established by saline lavage (arterial oxygen tension (Pa,O2)/inspiratory oxygen fraction (FI,O2) 17.8+/-9.6 kPa (134+/-72 mmHg)), and inflection point (Pflex) of the respiratory system was measured (6.6+/-1.4 cmH2O). Pa,O2/FI,O2 and CO of the supine and prone positions were obtained under the application of low PEEP and then under optimal PEEP (2 cmH2O below and above Pflex, respectively). The net increase in Pa,O2/FI,O2 by prone positioning was greater at low PEEP (27.3+/-12.0 kPa (205+/-90 mmHg)) than at optimal PEEP (4.4+/-13.0 kPa (33+/-98 mmHg)) (p=0.006). CO decreased significantly with optimal PEEP in the supine position (2.4+/-0.5 versus 3.1+/-0.4 L x min(-1) at baseline, p<0.001), and increased to 3.4+/-0.6 and 3.6+/-0.7 L x min(-1) in the prone position at 5 min and 30 min, respectively (both p=0.018). When the dogs were turned supine at optimal PEEP, CO again decreased (2.4+/-0.5 L x min(-1), p<0.001). In conclusion, the prone position augmented the effect of relatively low positive end-expiratory pressure on oxygenation, and attenuated the haemodynamic impairment of relatively high positive end-expiratory pressure in a canine acute lung injury model.

Animals↗

PubMed2001

Is a short trial of prone positioning sufficient to predict the improvement in oxygenation in patients with acute respiratory distress syndrome?

OBJECTIVE: To determine whether a 1-h trial of prone positioning is sufficient to identify responders. DESIGN: Prospective clinical cohort study in a medico-surgical ICU in a teaching hospital. PATIENTS: 49 patients with acute respiratory distress syndrome. INTERVENTIONS: A 6-h period of prone positioning. MEASUREMENTS AND RESULTS: Baseline measurements (blood gas analysis and respiratory parameters) were evaluated in supine position just prior to turning the patients prone. Measurements were then repeated 1 h after the beginning of prone positioning (PP1h) and at the end of the 6-h period of prone positioning (PP6h). The last measurements were performed 1 h after repositioning the patients supine. Prone position induced an increase in the PaO2/FIO2 ratio (p < 0.001). A response (increase in PaO2/FIO2 ratio of at least 20 % at PP1h and/or at PP6h) was observed in 37 of 49 patients (76%). Twenty-seven of these patients (73%) were responders at PP1h while 10 (27%) were responders only at PP6h- In all, two-thirds of the patients were considered persistent responders. However, whereas the PaO2/FIO2 ratio decreased significantly 1 h after repositioning the fast responders supine, the PaO2/ FIO2 ratio remained unchanged after repositioning slow responders. CONCLUSIONS: A short-term trial of prone positioning does not appear a sufficient method to identify patients who would benefit from the postural treatment.

APACHE↗

PubMed2006

Use of the prone position in the acute respiratory distress syndrome: how should we assess benefit?

Prone positioning of patients with acute respiratory failure was first suggested over 30 years ago. In the present issue of Clinical Science, Reutershan and co-workers have studied the changes in end-expiratory lung volume in 12 patients with ARDS (acute respiratory distress syndrome) over an 8 h period following manual turning from the supine to prone position. From the data presented, the authors suggest that baseline end-expiratory lung volume could be used to identify responders, and serial measurements would permit appropriate 'dosing' of the therapy. Although this is an interesting study that provides data that have rarely been collected when assessing the response to prone positioning, there are a number of limitations that need to be considered. However, despite the limitations, the study does stimulate a number of important questions related not only to the use of the prone position, but also to the management of patients with ARDS in general.

Blood Gas Analysis↗

PubMed2000

Oxygenation response to a recruitment maneuver during supine and prone positions in an oleic acid-induced lung injury model.

Prone position and recruitment maneuvers (RM) are proposed as adjuncts to mechanical ventilation to open up the lung and keep it open. We studied the oxygenation response to a RM (composed of a 30-s sustained inflation at 60 cm H(2)O airway pressure) performed in prone and supine positions in dogs after oleic acid- induced lung injury using an inspired O(2) fraction of 0.60. In one group (n = 6) first supine then prone positions were examined after a RM at 8 cm H(2)O and 15 cm H(2)O of positive end-expiratory pressure (PEEP). In the second group (n = 6) the sequence of positions was reversed. Prone positioning after supine position always improved oxygenation, whereas the decrement in Pa(O(2)) was relatively small when dogs were returned to the supine position. Oxygenation improved in both groups after a RM, and the improvement was sustained (after 15 min) in the prone position at 8 cm H(2)O of PEEP, but 15 cm H(2)O of PEEP was required in supine position. Our results suggest that a RM improves oxygenation more effectively with a decreased PEEP requirement for the preservation of the oxygenation response in prone compared with supine position.

Animals↗

PubMed2002

What is the optimal duration of ventilation in the prone position in acute lung injury and acute respiratory distress syndrome?

OBJECTIVE: To evaluate the effects of prone ventilation on respiratory parameters and extravascular lung water (EVLW) in patients with acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) in order to characterise the optimal duration of ventilation in the prone position. DESIGN: Prospective, observational study. SETTING: Nine-bed general intensive care unit. PATIENTS: Eleven patients with refractory hypoxaemia due to ALI/ARDS were prospectively investigated during 12 consecutive episodes of prone ventilation. INTERVENTIONS: Ventilation in the prone position for 18 h. MEASUREMENTS AND MAIN RESULTS: Measurements were obtained supine and after 1, 2, 6, 12 and 18 h in the prone position and 1 h after returning supine. There was a progressive improvement in PaO(2)/fraction of inspired oxygen (FIO(2)) ratio which reached significance after 12 h [121 (81-151) to 258 (187-329) torr; p<0.05]. EVLW index increased transiently at 1 h [14.2 (7.6-20.8) to 15.1 (9.0-20.2); p=0.05] and thereafter declined progressively and was significantly decreased at 18 h [12.1 (7.2-17.0); p=0.043]. The shunt fraction showed an early fall [0.41 (0.40-0.42) to 0.31 (0.30-0.32) at 1 h; p<0.001] preceding a subsequent progressive fall [0.22 (0.21-0.23) at 18 h; p<0.001]. CONCLUSIONS: Over the 18 h period studied there was progressive improvement in gas exchange, pulmonary shunt and EVLW. Although it is not possible to exclude that improvement over this period was unrelated to prone positioning, these findings suggests that ventilation in the prone position for more prolonged periods may be required for optimal improvement and warrants further study.

Adolescent↗

PubMed1991

The prone position for elbow arthroscopy.

Using the prone position for diagnostic and therapeutic arthroscopy improves intraoperative stability of the arm and allows the surgeon to approach the joint in a more intuitive manner. With this position, indications for elbow arthroscopy are increased and risks to neurovascular structures are reduced. Access to the posterior chamber is facilitated when the patient is in a prone position. This article describes both this arthroscopic technique and portal anatomy.

Arthroscopy↗

PubMed2006

Does gas exchange response to prone position predict mortality in hypoxemic acute respiratory failure?

OBJECTIVE: To determine whether gas exchange response to a first prone position session can predict patient outcome in hypoxemic acute respiratory failure. METHODS: Data from a previous multicenter randomized controlled trial were retrospectively analyzed for relationship between PaO(2)/FIO(2) ratio and PaCO(2) changes during the first 8-h prone position session to day 28 mortality rate; 370 prone position sessions were analyzed. Arterial blood gas was measured in supine position before proning and in prone position at the end of the session. Gas exchange improvement was defined as increase in the PaO(2)/FIO(2) ratio of more than 20% (PaO(2)R) or decrease in PaCO(2) of more than 1 mmHg (PaCO(2)R). MAIN RESULTS: The 28-day mortality rate was 26.5% in PaO(2)R-PaCO(2)R, 31.7% in PaO(2)R-PaCO(2)NR, 38.9% in PaO(2)NR-PaCO(2)R, and 43% in PaO(2)NR-PaCO(2)NR (log-rank 14.02, p = 0.003). In a Cox proportional hazards model the gas exchange response was a significant predictor to patient outcome with a 82.5% increase in risk of death in the case of PaO(2)NR-PaCO(2)R or PaO(2)NR-PaCO(2)NR, relative to the gas exchange improvement response (odds ratio 1.825). However, after adjusting for the difference in oxygenation between day 2 and day 1 the gas exchange response does no longer reach significance. CONCLUSION: In patients with hypoxemic acute respiratory failure initial improvement in gas exchange in the first PP session was associated with a better outcome, but this association disappeared when the change in oxygenation from day 1 to day 2 was taken into account, suggesting that underlying illness was the most important predictor of mortality in this patient population.

Blood Gas Analysis↗

PubMed1998

Prone position ultrasonography in silicone filled eyes.

PURPOSE: To evaluate the efficacy of a new technique of prone position ultrasonography in cases with silicone filled eyes. METHODS: Forty patients with prior pars plana vitrectomy and silicone oil instillation referred to a tertiary eye care centre were the subjects of this study. A prospective clinical trial was undertaken to evaluate the efficacy of prone position ultrasonography in addition to routinely performed supine position ultrasonography in these patients. The technique was undertaken by 2 independent observers and compared with the findings by indirect ophthalmoscopy or surgical results. Interobserver variability was also calculated. RESULTS: Two spikes were observed in supine position corresponding to the intravitreal silicone oil surface and the sclera, whereas a single spike corresponding to the sclera was observed in prone position. Supine position ultrasonography yielded a diagnostic accuracy of 61.8%, which increased to 96.7% when the procedure was supplemented with prone position ultrasonography. Specificity increased from 75 to 100% by the addition of this adjuvant procedure, however, with no significant difference in the interobserver variability ('K'=0.67 Vs 'K'= 0.62). CONCLUSION: Prone position ultrasonography is a useful adjunct to the routinely performed supine position ultrasonography in silicone filled eyes and increases the diagnostic yield.

Diagnostic Techniques, Ophthalmological↗

PubMed2006

Ventilation in the prone position in patients with acute lung injury/acute respiratory distress syndrome.

PURPOSE OF REVIEW: To contrast the beneficial effects of the prone position on the lungs and the lack of proven clinical benefits on patient outcome. RECENT FINDINGS: Recent human investigations in acute respiratory distress syndrome have shown that the prone position was able to abolish tidal expiratory flow limitation, to improve oxygenation in the case of localized infiltrates, to allow for reducing positive end-expiratory pressure level, and to reduce lung stress and strain. Experimental studies have confirmed that distribution of ventilation was more homogeneous in the prone position but showed that positive end-expiratory pressure affected ventilation distribution differently in the prone and in the supine position. Experimental work has also shown that proning reduced strains imposed on the lungs and made them more homogeneously distributed. Finally, one recent large randomized controlled trial of systematic proning in hypoxemic patients showed no reduction in mortality but less ventilator-associated pneumonia incidence in the prone position group. SUMMARY: The prone position is not systematically used in hypoxemic patients. Patients who could benefit from prone position sessions are those with the most severe acute respiratory distress syndrome and those with dorsal lung infiltrates. Whether this can be translated into improvement in patient outcome has yet to be tested in clinical trials.

Critical Care↗

PubMed1998

Use of the prone position in radiation treatment for women with early stage breast cancer.

PURPOSE: The prone position has been advocated for women with large pendulous breasts undergoing breast-conserving treatment with radiation therapy. However, there is no information in the literature regarding the coverage of the target volume with this technique. The purpose of this study was to evaluate the effectiveness of the prone treatment position in including at least the biopsy cavity with a 2-cm margin. METHODS AND MATERIALS: Eleven consecutive patients who underwent CT simulation in the prone position were included in this study. Patients underwent CT simulation in the prone position using a flat platform containing an aperture for the breast to hang through in a dependent fashion. CT slices were 5-mm thick taken at 3-mm intervals. The biopsy cavity was localized and outlined on sequential CT images using the surgical clips (when present) as well as the residual seroma. A 2-cm margin was included around the biopsy cavity to define the minimal target volume (mTV). Lateral fields were used for treatment planning. The beam arrangements were considered adequate if the mTV was totally included in the lateral fields. RESULTS: Median age of the patient population was 55 years. Bra sizes ranged from 36A-44DD. The majority of patients had mammographically detected T1 lesions. Median volume of the biopsy cavity was 48 cm3. Five of 11 (45%) patients underwent reexcision of the biopsy cavity, and 6 of 11 (55%) had surgical clips placed in the biopsy cavity. Overall, 8 of 11 (73%) patients did not have the entire mTV included in the lateral opposed tangential fields in the prone position. This was especially true in patients whose biopsy cavity extended down to the chest wall. There were no other clinical factors that could predict for the adequacy of coverage in the prone position. CONCLUSION: Special attention must be paid to the location of the surgical clips to determine the proximity of the biopsy cavity to the chest wall, or CT simulation should be performed to determine the exact location of the biopsy cavity prior to selecting patients with large pendulous breasts for treatment in the prone position.

Adult↗