Original article 162
A Rare Complication Due to Sulfuric Acid Ingestion A. M. Tamisani, C. Di
oto, E. Di Rovasenda
Summary "'---,--The aulhors present a case of pyloric and duodenal obstruclion in an 8-year-old child, resulting from accidenlal ingestion of sulfuric acid. A marked pyloric and duodenal cicatrizing stenosis re ulting from ingestion of sulfuric acid is seen infrequently, especially in pediatric age. Sulfuric acid produces a coagulation necrosis of lhe gastric mucosa and submucosa, and lhe process may im'oh-e the entire thickness of the gaslric wa1l, with subsequenl ulceralion and fibrosis. This dynamic palhophy iologic e\'enl imposes poslponement of surgical inlervention because of \'arious lime length between ingestion of acid and onsel of gastric outlet obstruction (17 days lo 5 years). Clinical features included postprandial epigastric distress, repeated non-biliou \'omiting, and marked weight loss. The authors also discuss lhe various surgical procedures that were employed to relieve the obstruction. Notwithslanding a potential risk of malignant evolution, a gastro-jejunostomy is the treatmenl of choice because of lhe age of lhe patient, and good po toperative results are confirmed by barium studies. Key words Corrosive bums of stomach cicatrization - Corrosive injuries
Gastric
Resume
Les auteurs presentent un cas d'obstruction pylorique et duodenale chez un patient de 8 ans, due a I'absorption d'acide sulfurique pour accumulateurs electriques. Frequernrnent nous avons a faire face a des stenoses par absorption de caustiques, moins frequemment aux consequences de I'absorption d'acides. L'absorption d'acide sulfurique est assez rare, surtout chez les enfants; I'acide sulfurique cause au debut une necrose avec coagulation de la muqueuse et de la sou -muqueuse gastrique, et puis on peut a"oir une perforation de la paroi gaslrique ou des stenoses el fibroses serrees. Ce processus physiopathologique se developpe dans des periodes de temps variables (17 jours - 5 ans).
Recei"ed :-':o"ember 29, 1991 Eur J Pediatr Surg 2 (1992) 162-16-1 © Hippokrates \'erlag Slutlgart ,\Iasson Editeur Paris
Du point de vue clinique, il se manifeste par une distension gastrique, un amaigrissement, de vomissements non-biliaires. Les auteurs discutenl les differenles lechniques chirurgicales et, meme s'ils liennent comple du risque polentiel de transformalion maligne, la gastrojejunostomie est a leur a\'is le lrailement de choix, en consideranll'age du patienl et res bons resullats oblenus. Mots-eles Lesion caustique de l'e tomac - Cicalrisation gastrique - Lesions causliques - Obstruction pylorique el duodenale - Absorption de caustiques Zusammenfassung \'erff. berichten über einen Fa1l einer Pylorus- und Duodenalstenose bei einem achtjährigen Kind, das versehentlich Schwefelsäure eingenommen halte. Eine ausgeprägte narbenbiJdende Slenose des Pylorus und Duodenums nach Einnahme von Schwefelsäure ist insbesondere im kindlichen Alter selten. Schwefelsäure verursacht eine Koagulationsnekrose der Magenschleimhaut und der Submukosa. Dieser Vorgang kann die gesamte Dicke der Magenwand in Mitleidenschaft ziehen, mit nachfolgender Ulzeration und Fibrose. Diese Pathophysiologie bedingt einen chirurgischen Eingriff oft erst 17 Tage und 5 Jahre nach Säureeinnahme. Klinisch zeigten sich epigastrische postprandiale Beschwerden, wiederholtes nichtgallehaltiges Erbrechen und starke Gewichtsabnahme. Verff. diskutieren auch die verschiedenen chirurgischen 1aßnahmen, die zur Beseitigung der Ob truktion ergriffen wurden. Trotz des potentie1len Risikos einer malignen Enlwicklung war wegen des Alters des Patienlen eine Gastrojejunostomie die Methode der Wahl. BariumKontrastuntersuchungen bestätigten das gute postoperative Ergebnis. Sehl üsselwörter Schwefelsäurenverätzung - Pylorusstenose - Duodenalstenose - \'ernarbung des ,\ \agens - \'erätzende ~ \'erletzungen
Downloaded by: University of Pennsylvania Libraries. Copyrighted material.
Surgical Emergenc)' and Pediatric Surgery Department, Giannina Gaslini Institute, Genoa, llal)'
Introduction Quite frequenUy we have to face complications due to caustic ingestion and, Iess frequently, those following from acid ingestion. Alkalies cause severe injuries to the esophagus, generally sparing the stomach: the epithelial tissue eoating the esophagus is particularly sensitive to alkaline agents; lesions can be more or less deep, causing quite frequentIy perforations or cicatricial stenosis which are difficult to treat. On the other hand, the esophageal mucosa is more resislanllo acid agents, which on lhe conlrary lend to injure gastric walls, in particular lhose of anlrum and pylorus. According lo several authors, only in 20 % of cases the slomach can show an inflammalory reaction and scarring of the mucosa due lo the ingeslion of alkali. According lo lhe lileralure, lhe agents mosl frequenlly in\'o!\-ed are: hydrochloric acid, sulfuric acid, nitric acid, zinc hydrochloride (1,2). Our study is aimed al presenling lhe severe effects of lhe accidenlal ingeslion of sulfuric acid on lhe pylorus walls and on lhe firsl portio of lhe duodenum in an 8-year-old child
EurJ Pediatr Surg 2 (1992) conformation, hypotonie esophagus and wide open cardia, considerab!e increase in lhe secrelion of gastric juice (about 200 ce), and especially the lack of a pyloric transit. Ultrasonography (Fig. 2) of the abdomen shows lhickened anlral region walls. The pylorus also presenls lhiek walls and lhe exam in real time does nol show any transil of material lhrough lhe pyloric canal. Besides, the walls of lhe first part of lhe duodenum appear 10 be involved, the central part seems diJated with liquid inside; no peristaIsis is el-ident. A control gaslroscopy is performed, sho\l'ing hypotonie esophagus, absence of slenosis, no lesions found at the gaslric body and fundus, except a pyloric anlrum wilh cicatricial stenosis ciosed on the ulcer area shown by lhe firsl gastroscopy. At 50 days from the accidenl, an operation of gaslro-enlero-anaslomosis is performed: lhe palpation of lhe antra! region sho\\'s a considerable in-
l\laterials and methods A. E. is an 8-.rear-old child \I-e obselTed \\ay I \J\J I for the accidental ingestion of sulfuric acid used for car batteries. The patient presents I"omiting episodes \\'ith hematemesis. The gastroscopy sho\\s an ulcer in the antral region. A nasogastric tube is applied, antibiotic and H2 antagonist therapy is stal1ed. At I1 days from the accidenl. the patient begins to present frequent episodes of \'omiting, with subsequent \I'eight loss. so that TP\I (Total Parenteral \Iutrition) is stal1ed. An x-ray (Fig. I) of the esophagus demonstrates: regular esophageal
Fig. 1 Esophagus x-ray regular esophageal eontours, wlde open eardlas wlth hypotonie tower esophagus. markedly Inereased gastrle JUice seeretlon, total pylone stenosIs
163
Fig. 2 Abdominal ultrasonography. thlekened antral walls, thlekened pylorle walls, pylone stenosIs
Fig. 3 X-ray after 3 months normal stomaeh. no Irregulanty of ItS eontours. good funellon of the gastro-entero-anastomOSIS
Downloaded by: University of Pennsylvania Libraries. Copyrighted material.
A Rare Complication Due to Suljitric Acid Ingestion
Eur J Pediatr Surg 2 (J 992)
crease in wall lhicknes , lhe exploration of lhe gaslric ca\-ity does not allow to detect an)' patency of the pyloric canal. Afterwards, a gaslrojejunal transmesocholic isoperi laltic anastomosis on two la)'ers is performed. The post-operative course is good and lhe patient is discharged 20 days after lhe operation. An x-ra)' (Fig. 3) control after 3 monlhs shows anormal stomach without any deteclable alterations on the greater curvature and a regular function of gastroenteric anastomo iso
Diseussion In 1828 Robert deseribed for lhe firsllime a palienl who died for ulcerali\'e corrosi\'e gaslrilis (2). In 1948 Gray of lhe.\ \ayo Clinie (2) publi hed an imporlant work on pylorie stenosis due lo ingeslion of corrosi\'e agents. In our re\iew of lhe lileralure of lhe lasl years, we found only lwo cases of pylorie eiealricial stenosi: a 2-year-old palienl wilh duodenal pyloro-anlraI and gastro-e ophageal junetion stenosis due to eauslic soda ingeslion (7) and a 6-year-old palienl wilh pyloric slenosis due lo nilric aeid ingeslion (4). Hydroehloric acid appears to be the agent \\'hich more frequently can produce scarring of lhe slomach. Sulfuric acid is reporled lo have been a frequenl eause of inflammalory reaelions and ulceralion wh ich lead lo perforation and gang rene. This agenl, on contacl \\ilh lhe gaslric wall, causes a coagulative necrosis of lhe mucosa and submucosa wilh lhrombosis of inlramural vessels, ulceralion and fibrosis, lhus affecling lhe whole thiekness of lhe ga lrie walJ (3). The severity of lhe injury ob\1.ously depends on lhe quanlity of lhe ingesled sub lanee, on its concenlration and on lhe duration of the contact; besides, the presence of food and lhe pyloric sphincler tonicity ean decrease or increase lhe injuring effecl of lhe acid. According lo many aulhors, lhe seleclive lesion of lhe prepyloric 01' pyloric region is due lo: I) a reflex pylorospa m wilh stasis of acid in lhal area; 2) an increased sensiti\1.ty of lhe antral epithelium lo the acid agent (5). Stenosis generally develops in aperiod of time (7) ranging between 4 and 6 weeks (early ca es of 17 days and lale cases of 5 years have been described). Metabolie alkalosis is rare in palients wilh corrosive ga tric obstruction; in facl, vomit has a low aeid conlenl, an effect of astate of histaminic achlorhydria; in everal pa-
A. 1\1. Tamisani et al
tients, hyponatremia, hypokalemia, hypalbuminemia were observed. X-ray performed after some weeks can demonslrate gastric di tension and suspecl lesions of lhe pylorus; ullra- ound scanning of the abdomen and gastroscopy must be performed: in facl, the surgicaJ treatmenl musl nol be immediate. The pyloroplasty is advisable only in seleeted cases wüh localized pyloric lenosis. Billrolh I partial gastrectomy is ad\1. able in cases of heallhy duodenum and \\'hen lhe slenosis affeets the di taI slomach; some aulhors prefer Billrolh 11 operalion (I). In anyea e, many aulhors agree on lhe good results obtained with lhe gastro-jejunal anaslomosis, considering lhe histarninie aehlOl-hydria whieh ean be demonslraled in such palients. We have preferred lhis technique. as we had lo lreal a most severe pedialrie ga tro-duodenal slenosis.
References GiinmollZ. DlIrsl.lL: Acid corrosi'·ega,lrilis. AmJ Surg 1.1 I (HJ81) 381383 2 Gra)' "L, Holm", CL Pdoric sleno,i, caused b.1 ingeslion of corrosi\'e substances: report of ca;e. S Clin :'\orth .\m 28 (I (118) 1011 :l L)'lIu.'ood ""nil/gloll) Sleno,i, of anlrum and pmximal duodenum resulling from lhe inge,lIon of a corrosi\'e agent. Am J Surg 101 (196-1) 580585 I Pacllf'co), I 'UurillO .-\. GOIll"~ FraUe A. el al: O,lruccion pilorica POl' I
inge,la de acida nilrico. x,'"X CongröO Soc Espanola Cirugia Pedialrica Alti, 1990. pp. 60-61 5 Palmer ED, Scott .\I.\': Obsen'alion on gaslric mucosa follo\\ ing ingestion of hydrochloric acid. Gastroenterology 12 (J 9.19) 819-883 fi Roberl S. quoled by .\laclahall 5' Pyloric occlusion following the ingestion of corrosi"e liquids. JA.\IA 205 (1931) 883-88.1 7 5l1bbarao /{SI'J":' I,asar .-\1{, el al: Cicatrical gaslric stenosis caused by corrosive ingestion. Aus 'J7...J Surg 58 (1988) J .13-1·16
A. ,11. Tamisani, M.D.
Surgical Emergenc)' and Pediatric Surgery Department Giannina Gaslini Institute Largo G. Gaslini, 5 1- I6 I48 Geno\'a Quarto, ltal)'
Downloaded by: University of Pennsylvania Libraries. Copyrighted material.
164
A Rare Complication Due to Sulfuric Acid Ingestion A. M. Tamisani, C. Di
oto, E. Di Rovasenda
Summary "'---,--The aulhors present a case of pyloric and duodenal obstruclion in an 8-year-old child, resulting from accidenlal ingestion of sulfuric acid. A marked pyloric and duodenal cicatrizing stenosis re ulting from ingestion of sulfuric acid is seen infrequently, especially in pediatric age. Sulfuric acid produces a coagulation necrosis of lhe gastric mucosa and submucosa, and lhe process may im'oh-e the entire thickness of the gaslric wa1l, with subsequenl ulceralion and fibrosis. This dynamic palhophy iologic e\'enl imposes poslponement of surgical inlervention because of \'arious lime length between ingestion of acid and onsel of gastric outlet obstruction (17 days lo 5 years). Clinical features included postprandial epigastric distress, repeated non-biliou \'omiting, and marked weight loss. The authors also discuss lhe various surgical procedures that were employed to relieve the obstruction. Notwithslanding a potential risk of malignant evolution, a gastro-jejunostomy is the treatmenl of choice because of lhe age of lhe patient, and good po toperative results are confirmed by barium studies. Key words Corrosive bums of stomach cicatrization - Corrosive injuries
Gastric
Resume
Les auteurs presentent un cas d'obstruction pylorique et duodenale chez un patient de 8 ans, due a I'absorption d'acide sulfurique pour accumulateurs electriques. Frequernrnent nous avons a faire face a des stenoses par absorption de caustiques, moins frequemment aux consequences de I'absorption d'acides. L'absorption d'acide sulfurique est assez rare, surtout chez les enfants; I'acide sulfurique cause au debut une necrose avec coagulation de la muqueuse et de la sou -muqueuse gastrique, et puis on peut a"oir une perforation de la paroi gaslrique ou des stenoses el fibroses serrees. Ce processus physiopathologique se developpe dans des periodes de temps variables (17 jours - 5 ans).
Recei"ed :-':o"ember 29, 1991 Eur J Pediatr Surg 2 (1992) 162-16-1 © Hippokrates \'erlag Slutlgart ,\Iasson Editeur Paris
Du point de vue clinique, il se manifeste par une distension gastrique, un amaigrissement, de vomissements non-biliaires. Les auteurs discutenl les differenles lechniques chirurgicales et, meme s'ils liennent comple du risque polentiel de transformalion maligne, la gastrojejunostomie est a leur a\'is le lrailement de choix, en consideranll'age du patienl et res bons resullats oblenus. Mots-eles Lesion caustique de l'e tomac - Cicalrisation gastrique - Lesions causliques - Obstruction pylorique el duodenale - Absorption de caustiques Zusammenfassung \'erff. berichten über einen Fa1l einer Pylorus- und Duodenalstenose bei einem achtjährigen Kind, das versehentlich Schwefelsäure eingenommen halte. Eine ausgeprägte narbenbiJdende Slenose des Pylorus und Duodenums nach Einnahme von Schwefelsäure ist insbesondere im kindlichen Alter selten. Schwefelsäure verursacht eine Koagulationsnekrose der Magenschleimhaut und der Submukosa. Dieser Vorgang kann die gesamte Dicke der Magenwand in Mitleidenschaft ziehen, mit nachfolgender Ulzeration und Fibrose. Diese Pathophysiologie bedingt einen chirurgischen Eingriff oft erst 17 Tage und 5 Jahre nach Säureeinnahme. Klinisch zeigten sich epigastrische postprandiale Beschwerden, wiederholtes nichtgallehaltiges Erbrechen und starke Gewichtsabnahme. Verff. diskutieren auch die verschiedenen chirurgischen 1aßnahmen, die zur Beseitigung der Ob truktion ergriffen wurden. Trotz des potentie1len Risikos einer malignen Enlwicklung war wegen des Alters des Patienlen eine Gastrojejunostomie die Methode der Wahl. BariumKontrastuntersuchungen bestätigten das gute postoperative Ergebnis. Sehl üsselwörter Schwefelsäurenverätzung - Pylorusstenose - Duodenalstenose - \'ernarbung des ,\ \agens - \'erätzende ~ \'erletzungen
Downloaded by: University of Pennsylvania Libraries. Copyrighted material.
Surgical Emergenc)' and Pediatric Surgery Department, Giannina Gaslini Institute, Genoa, llal)'
Introduction Quite frequenUy we have to face complications due to caustic ingestion and, Iess frequently, those following from acid ingestion. Alkalies cause severe injuries to the esophagus, generally sparing the stomach: the epithelial tissue eoating the esophagus is particularly sensitive to alkaline agents; lesions can be more or less deep, causing quite frequentIy perforations or cicatricial stenosis which are difficult to treat. On the other hand, the esophageal mucosa is more resislanllo acid agents, which on lhe conlrary lend to injure gastric walls, in particular lhose of anlrum and pylorus. According lo several authors, only in 20 % of cases the slomach can show an inflammalory reaction and scarring of the mucosa due lo the ingeslion of alkali. According lo lhe lileralure, lhe agents mosl frequenlly in\'o!\-ed are: hydrochloric acid, sulfuric acid, nitric acid, zinc hydrochloride (1,2). Our study is aimed al presenling lhe severe effects of lhe accidenlal ingeslion of sulfuric acid on lhe pylorus walls and on lhe firsl portio of lhe duodenum in an 8-year-old child
EurJ Pediatr Surg 2 (1992) conformation, hypotonie esophagus and wide open cardia, considerab!e increase in lhe secrelion of gastric juice (about 200 ce), and especially the lack of a pyloric transit. Ultrasonography (Fig. 2) of the abdomen shows lhickened anlral region walls. The pylorus also presenls lhiek walls and lhe exam in real time does nol show any transil of material lhrough lhe pyloric canal. Besides, the walls of lhe first part of lhe duodenum appear 10 be involved, the central part seems diJated with liquid inside; no peristaIsis is el-ident. A control gaslroscopy is performed, sho\l'ing hypotonie esophagus, absence of slenosis, no lesions found at the gaslric body and fundus, except a pyloric anlrum wilh cicatricial stenosis ciosed on the ulcer area shown by lhe firsl gastroscopy. At 50 days from the accidenl, an operation of gaslro-enlero-anaslomosis is performed: lhe palpation of lhe antra! region sho\\'s a considerable in-
l\laterials and methods A. E. is an 8-.rear-old child \I-e obselTed \\ay I \J\J I for the accidental ingestion of sulfuric acid used for car batteries. The patient presents I"omiting episodes \\'ith hematemesis. The gastroscopy sho\\s an ulcer in the antral region. A nasogastric tube is applied, antibiotic and H2 antagonist therapy is stal1ed. At I1 days from the accidenl. the patient begins to present frequent episodes of \'omiting, with subsequent \I'eight loss. so that TP\I (Total Parenteral \Iutrition) is stal1ed. An x-ray (Fig. I) of the esophagus demonstrates: regular esophageal
Fig. 1 Esophagus x-ray regular esophageal eontours, wlde open eardlas wlth hypotonie tower esophagus. markedly Inereased gastrle JUice seeretlon, total pylone stenosIs
163
Fig. 2 Abdominal ultrasonography. thlekened antral walls, thlekened pylorle walls, pylone stenosIs
Fig. 3 X-ray after 3 months normal stomaeh. no Irregulanty of ItS eontours. good funellon of the gastro-entero-anastomOSIS
Downloaded by: University of Pennsylvania Libraries. Copyrighted material.
A Rare Complication Due to Suljitric Acid Ingestion
Eur J Pediatr Surg 2 (J 992)
crease in wall lhicknes , lhe exploration of lhe gaslric ca\-ity does not allow to detect an)' patency of the pyloric canal. Afterwards, a gaslrojejunal transmesocholic isoperi laltic anastomosis on two la)'ers is performed. The post-operative course is good and lhe patient is discharged 20 days after lhe operation. An x-ra)' (Fig. 3) control after 3 monlhs shows anormal stomach without any deteclable alterations on the greater curvature and a regular function of gastroenteric anastomo iso
Diseussion In 1828 Robert deseribed for lhe firsllime a palienl who died for ulcerali\'e corrosi\'e gaslrilis (2). In 1948 Gray of lhe.\ \ayo Clinie (2) publi hed an imporlant work on pylorie stenosis due lo ingeslion of corrosi\'e agents. In our re\iew of lhe lileralure of lhe lasl years, we found only lwo cases of pylorie eiealricial stenosi: a 2-year-old palienl wilh duodenal pyloro-anlraI and gastro-e ophageal junetion stenosis due to eauslic soda ingeslion (7) and a 6-year-old palienl wilh pyloric slenosis due lo nilric aeid ingeslion (4). Hydroehloric acid appears to be the agent \\'hich more frequently can produce scarring of lhe slomach. Sulfuric acid is reporled lo have been a frequenl eause of inflammalory reaelions and ulceralion wh ich lead lo perforation and gang rene. This agenl, on contacl \\ilh lhe gaslric wall, causes a coagulative necrosis of lhe mucosa and submucosa wilh lhrombosis of inlramural vessels, ulceralion and fibrosis, lhus affecling lhe whole thiekness of lhe ga lrie walJ (3). The severity of lhe injury ob\1.ously depends on lhe quanlity of lhe ingesled sub lanee, on its concenlration and on lhe duration of the contact; besides, the presence of food and lhe pyloric sphincler tonicity ean decrease or increase lhe injuring effecl of lhe acid. According lo many aulhors, lhe seleclive lesion of lhe prepyloric 01' pyloric region is due lo: I) a reflex pylorospa m wilh stasis of acid in lhal area; 2) an increased sensiti\1.ty of lhe antral epithelium lo the acid agent (5). Stenosis generally develops in aperiod of time (7) ranging between 4 and 6 weeks (early ca es of 17 days and lale cases of 5 years have been described). Metabolie alkalosis is rare in palients wilh corrosive ga tric obstruction; in facl, vomit has a low aeid conlenl, an effect of astate of histaminic achlorhydria; in everal pa-
A. 1\1. Tamisani et al
tients, hyponatremia, hypokalemia, hypalbuminemia were observed. X-ray performed after some weeks can demonslrate gastric di tension and suspecl lesions of lhe pylorus; ullra- ound scanning of the abdomen and gastroscopy must be performed: in facl, the surgicaJ treatmenl musl nol be immediate. The pyloroplasty is advisable only in seleeted cases wüh localized pyloric lenosis. Billrolh I partial gastrectomy is ad\1. able in cases of heallhy duodenum and \\'hen lhe slenosis affeets the di taI slomach; some aulhors prefer Billrolh 11 operalion (I). In anyea e, many aulhors agree on lhe good results obtained with lhe gastro-jejunal anaslomosis, considering lhe histarninie aehlOl-hydria whieh ean be demonslraled in such palients. We have preferred lhis technique. as we had lo lreal a most severe pedialrie ga tro-duodenal slenosis.
References GiinmollZ. DlIrsl.lL: Acid corrosi'·ega,lrilis. AmJ Surg 1.1 I (HJ81) 381383 2 Gra)' "L, Holm", CL Pdoric sleno,i, caused b.1 ingeslion of corrosi\'e substances: report of ca;e. S Clin :'\orth .\m 28 (I (118) 1011 :l L)'lIu.'ood ""nil/gloll) Sleno,i, of anlrum and pmximal duodenum resulling from lhe inge,lIon of a corrosi\'e agent. Am J Surg 101 (196-1) 580585 I Pacllf'co), I 'UurillO .-\. GOIll"~ FraUe A. el al: O,lruccion pilorica POl' I
inge,la de acida nilrico. x,'"X CongröO Soc Espanola Cirugia Pedialrica Alti, 1990. pp. 60-61 5 Palmer ED, Scott .\I.\': Obsen'alion on gaslric mucosa follo\\ ing ingestion of hydrochloric acid. Gastroenterology 12 (J 9.19) 819-883 fi Roberl S. quoled by .\laclahall 5' Pyloric occlusion following the ingestion of corrosi"e liquids. JA.\IA 205 (1931) 883-88.1 7 5l1bbarao /{SI'J":' I,asar .-\1{, el al: Cicatrical gaslric stenosis caused by corrosive ingestion. Aus 'J7...J Surg 58 (1988) J .13-1·16
A. ,11. Tamisani, M.D.
Surgical Emergenc)' and Pediatric Surgery Department Giannina Gaslini Institute Largo G. Gaslini, 5 1- I6 I48 Geno\'a Quarto, ltal)'
Downloaded by: University of Pennsylvania Libraries. Copyrighted material.
164
