congenital bochdalek hernia ( cbh ) develops as a result of the inappropriate fusion of the pleuroperitoneal fold and septum transversum at the site of the posterolateral lumbocostal trigone at the sixth week of gestation .
this entity was first described by mccauley in 1754 and then by vincent alexander bochdalek in 1848 .
this type of diaphragmatic hernia is considered a perinatal disease that presents a few hours after birth , or in early infancy , and it is associated with significant morbidity and mortality .
cbh in adults is very rare ; it remains asymptomatic until adulthood and generally presents with thoracic and/or abdominal symptoms aggravated in supine position .
we present a case of left - sided congenital bochdalek hernia that remained asymptomatic and was discovered incidentally during secondary cytoreductive surgery for epithelial ovarian cancer ; in this patient , a iatrogenic diaphragmatic defect was found , hyperthermic intraperitoneal chemotherapy ( hipec ) was performed and early postoperative bilateral anterior thalamic infarction developed .
a 46-year - old female patient with a bmi of 25 was referred to our tertiary center ( cerrahpasa medical faculty , gynecological oncology unit ) in august 2016 with the diagnosis of platinum - resistant ovarian cancer .
positron emission tomography and computed tomography ( ct ) revealed implants on the right diaphragmatic surface after first - line adjuvant chemotherapy . she has never had any thoracic or abdominal symptoms and no history of major trauma . initial preoperative evaluation of the patient revealed no significant sign of diaphragmatic hernia .
her physical examination was normal , including chest auscultation sounds and chest x - ray .
thoracic ct did not reveal any abnormal image that could be evaluated as a diaphragmatic hernia .
she was placed in flank position , and , under general anesthesia , laparotomy was performed .
an oval defect with the dimensions of 3  4 cm was seen in the left posterolateral site of the diaphragm ( fig .
the most distal portion of the inferior lobe of the left lung was visible through the defect during inspiration and expiration movements .
drainage chest tubes were inserted bilaterally via the 6th intercostal spaces to avoid leakage of the chemotherapeutic agents across repaired diaphragm and postoperative massive pleural effusion .
the tissue around the congenital left - sided defect was excised circularly and the defect itself was repaired with interrupted nonabsorbable monofilament sutures .
after complete cytoreduction had been achieved , hyperthermic intraperitoneal chemotherapy with doxorubicin 35 mg / m and paclitaxel 175 mg / m for 60 min at 42.5c was delivered .
no leakage via drainage tubes from the thoracic cavity was noted during the procedure . during the surgery ,
the patient was managed by standard monitoring , which involved continuous monitoring of electrocardiography , invasive blood pressure , central venous pressure , pulse oximetry , body temperature and hourly urine output .
arterial samples were drawn at regular periods for the determination of electrolytes , acid base status and hematocrit .
finally , the operation lasted 4 h. at the end of the surgery , the patient remained intubated and was transferred to the intensive care unit for monitoring ongoing resuscitation along with fluid and electrolyte management .
the patient was extubated 10 h after completion of surgery , and was transferred to the service on the 2nd postoperative day .
prophylactic enoxaparin 4,000 iu was started 6 h after surgery . on the 3rd and 4th postoperative day , excessive sleepiness throughout the day and dyspraxia was noted . bilateral anterior thalamic infarction caused by emboli that block the thalamosubthalamic artery
the dose of enoxaparin was changed from 4,000 iu once a day to 800 iu twice a day .
follow - up at 4 months after surgery showed no evidence of recurrence and no symptom regarding thalamic infarct .
cbh generally presents in newborns with severe respiratory failure or in infancy due to herniation and/or strangulation of the abdominal contents .
one of the best studies concerning the incidence of the defect in adults was carried out by mullins et al . , who reviewed 13,138 ct scans .
their study revealed an incidence of 0.17% , with 68% being right - sided defects and 77% of the patients being female .
since the second study summarized symptomatic cases , demographics identified were different than those in asymptomatic ones .
this difference showed that more cases of right - sided cbh in females may remain silent than left - sided cases .
these data were supported by several case reports . nevertheless , in our case , the defect was noted on the left side . also , no herniation of intestinal loops was noted , and the patient has never had any thoracic or abdominal symptom that might be related to diaphragmatic hernia .
diagnosis of the disease might be carried out by chest ct when there are clinically unexplained thoracic and abdominal symptoms .
the chest ct of our patient did not reveal any of the above - mentioned patterns .
there are several cases concerning surgical repair of the defect  both laparoscopic , via laparotomy , and through the thoracic cavity .
we performed upper midline incision for laparotomy , and there was no need for another access to carry out the repair of the diaphragmatic defect .
repair of diaphragmatic defect can be performed by various techniques , using absorbable or nonabsorbable sutures in an interrupted or continuous fashion . from our point of view
, surgeons may choose any of them provided that they are comfortable with the procedure .
the main reason for using bilateral chest tubes was to prevent massive pleural effusion due to hipec .
in addition , intra - abdominal pressure increases during hipec , which may subsequently cause a cephalad shift of the diaphragm to increase peak airway pressures and reduce residual capacity .
chest drains which were inserted prior to hipec reduce the increase in peak airway pressure , and by this way , the length of the intubation period and hospital stay can be decreased .
malignancy itself , hipec , central venous cannulation , the position of the patient 's neck , sudden blood loss and a long duration of the operation were noted as possible risk factors in our case . in conclusion , although congenital bochdalek hernia commonly occurs in the newborn and infancy period , it must not be excluded in the case of unexplained abdominal and/or thoracic symptoms in adults . despite the fact that this kind of rare condition presents with pain , obstruction symptoms or pulmonary symptoms , it can be silent until discovered incidentally .
secondly , cerebral embolism should be suspected in the presence of any neurological symptom in postoperative patients .
 congenital bochdalek hernia is a defect of the diaphragm and very rare in adults . 
 only around 100 cases have been reported in the literature . herein , we present a case with a recurrent ovarian cancer who underwent secondary cytoreductive surgery and hyperthermic intraperitoneal chemotherapy . 
 an oval defect with dimensions of 3  4 cm was seen in the left posterolateral site of the diaphragm during surgical exploration . 
 in addition , a 6  3 cm iatrogenic right - sided diaphragmatic defect was found and repaired . in the early postoperative period , 
 a bilateral thalamic infarction occurred . 