11.
Chylous ascites
is the accumulation of chyle within the peritoneal cavity. Which of the
following statement(s) is/are true concerning chylous ascites?
a.
The cisterna
chyli lies at the anterior surface of the first and second lumbar vertebrae and
receives lymphatic fluid from the mesenteric lymphatics
b.
Chylous ascites
is most commonly associated with abdominal lymphoma
c.
Paracentesis and
analysis of chylous fluid typically reveals elevated triglycerides, protein,
and leukocyte levels with cytologic analysis reflecting the underlying presence
of malignancy
d.
Treatment of
chylous ascites with dietary manipulation will be successful in most cases
e.
The mortality
rate in adults with chylous ascites is in excess of 50%
Answer: a,
b, e
Chylous
ascites is accumulation within the peritoneal cavity of chyle, a lymphatic
fluid with a high lipid content. Access of intestinal lipids to the circulation
is via mesenteric lymphatics that enter the cisterna chyle, which in turn
becomes the thoracic duct which eventually enters the venous system at the
junction of the left subclavian and internal jugular veins. The cisterna chyli
lies at the anterior surface of the first and second lumbar vertebrae slightly
to the right of the aorta. Chylous ascites may result from injury to major
lymphatic duct or the cisterna. However for lymphatic leakage to persist,
widespread occlusion of lymphaticovenous collaterals within the abdomen must be
present. Malignancy is the predominant cause (88%) of spontaneous chylous
ascites in adults, with lymphoma the most common malignancy. Diagnostic studies
must include not only documentation of lymphatic origin of the abdominal fluid
but also an attempt to delineate the cause of chylous ascites. Paracentesis and
analysis of chylous fluid typically reveals elevated triglycerides, protein,
and leukocyte levels, with a predominance of lymphocytes. Unfortunately,
cytology is seldom positive despite the presence of malignancy.
Lymphangiography may define the site of lymphatic leak for patients in whom the
leak is from the cisterna or retroperitoneal lymphatics but not when from the
mesenteric or hepatic lymphatics. Of noninvasive studies, CT is the test of
choice, with a high diagnostic yield in nontraumatic chylous ascites in adults.
Frequently, laparotomy with node biopsy is required for histology and typing in
cases suspected to be cancer, particularly for lymphoma. Treatments for chylous
ascites have been directed toward decreasing lymph and triglyceride
accumulation. Successful resolution of chylous ascites has been achieved using
a fat-restricted diet with added medium-chain triglycerides in an attempt to
reduce lymphatic transport of triglycerides and perhaps intestinal lymph flow.
Although there have been reports of success using such dietary manipulation,
many failures have been reported. Therefore, in most patients with chylous
ascites, treatment is likely to be successful only when directed toward the
underlying cause. For patients with lymphoma, therapy effective against
lymphoma is likely to eliminate chylous ascites.
The
prognosis for patients with chylous ascites is much better in infants and
children than in adults, principally because of the differences in causes of
the condition. A mortality of 21% is reported in infants and children whereas a
mortality of 88% has been noted in adults. Patients with chylous ascites with
associated neoplasms typically have the gravest prognosis.
12.
Which of the
statement(s) is/are true concerning laparoscopic hernia repair?
a.
General
anesthesia is required
b.
Either an
abdominal or preperitoneal approach is possible
c.
The use of
prosthetic mesh is required in all variations
d.
Long-term results
suggest that the laparoscopic approach is equal or better than traditional
repairs
Answer: a,
b, c
The
laparoscopic approach to the repair of groin hernias has been recently
developed. Either a transabdominal approach, wherein the peritoneum in the
inguinal area is opened, and the repair is performed in the preperitoneum or an
entirely preperitoneal approach can be used. In either technique, which are both
performed under general anesthesia, after reducing the visceral contents out of
the hernia, the repair is performed by placing a sheet of prosthetic mesh over
the internal aspect of the inguinal floor and internal ring. Although early
results and short-term benefits appear promising, long-term follow-up data is
still not available to compare these techniques with traditional repairs.
13.
A 28-year-old
woman with a history of an appendectomy presents with a nontender palpable mass
in the right lower quadrant abdominal incision. The following statement(s)
is/are true concerning the diagnosis and management of this patient.
a.
The best
diagnostic test involves imaging of the abdominal wall by either CT or MRI
b.
Resection of the
mass with a 2 cm margin is usually adequate
c.
Low dose
radiation is a suitable alternative to surgery for primary treatment
d.
Re-resection for
recurrence will likely have a higher rate of recurrence than for primary
resection
Answer: a
Desmoid
tumors are fibromatous tumors that may resemble low-grade fibrosarcoma but
never metastasize. The tumor often infiltrates adjacent muscle and has a high
incidence of recurrence despite seemingly adequate gross resection. The highest
frequency is in women of childbearing age of which over 90% of tumors are
abdominal in location. For abdominal wall desmoid tumors, approximately
one-third are associated with a previous operation at the tumor site. The most
frequent presenting symptom is a nontender, palpable abdominal wall mass.
Diagnostic imaging is best carried out by CT or MRI, which delineate the extent
of involvement of the layers of the abdominal wall and potential
intraperitoneal extension. Initial treatment of abdominal wall desmoid tumors
is surgical. Because the margins of the tumor are not easily determined and
because the tumor often infiltrates muscle and periosteum, limited margins
around the gross tumor frequently result in microscopic tumor at the margin.
Recurrence rates for abdominal desmoid tumors vary from 9% to 40%, and
recurrence is frequent with inadequate margins. A 5-cm margin of resection is
considered adequate with mono bloc resection of rib cage, pubic or iliac bone
or involved portions of organs such as bladder to achieve these margins.
Reconstruction of the abdominal wall with polypropylene mesh is necessary in
most cases. In patients in whom adequate margins of resection are achieved,
there is no benefit from adjuvant radiotherapy. Second and third resections
after recurrence have been associated with no higher rate of recurrence than
primary resection. Radiotherapy alone has achieved local control in desmoid
tumor in as many as 100% of tumors treated primarily and 75% of recurrent
tumors. Radiation doses at least 60 Gy are considered necessary for consistent
control. The large radiation dose risks major damage to adjacent bowel and
therefore primary radiation treatment of abdominal wall desmoid tumors has a
limited role.
14.
Which of the
following statement(s) is/are true concerning repair of inguinal hernias?
a.
The Bassini
repair approximates the transversus abdominis aponeurosis and transversalis
fascia and the shelving edge of the inguinal ligament.
b.
The Bassini
repair is an adequate repair for a femoral hernia
c.
A relaxing
incision is important for repairs of direct and large indirect inguinal hernias
to prevent excessive tension in the closure
d.
An advantage to
the use of prosthetic material is the mesh incites formation of scar tissue to
further increase tensile strength provided by the mesh alone
Answer: a,
c, d
The Bassini
repair is an inguinal hernia repair used world-wide and has been the standard
against which other repairs are judged. The repair involves approximation of
the transversus abdominis aponeurosis and transversalis fascia and the lateral
edge of the rectus sheath to the shelving edge of the inguinal ligament. A
femoral hernia cannot be repaired by the Bassini repair because the orifice to
the femoral canal lies deep to the inguinal ligament. A Cooper’s ligament
repair does approximate the structures to the transversalis fascia of the
pectineal (Cooper’s) ligament between the pubic tubercle and the femoral vein
and therefore is appropriate for repair of a femoral hernia. A relaxing
incision for repairs of direct and large indirect inguinal hernias prevents
excessive tension in the closure. There are an increasing number of proponents
for the use of prosthetic material for the routine repair of inguinal hernias.
Prosthetic material, such as polypropylene mesh, have been used for years for
repair of large or recurrent inguinal and femoral hernias. The prosthetic mesh
provides a low-tension repair for such large defects which otherwise could not
be closed without excessive tension. In addition, the mesh incites the
formation of scar tissue to further increase tensile strength beyond that
provided by mesh alone. Results reported for inguinal hernia repairs using mesh
have been excellent, although there is a slight risk of infection of the
prosthetic material which must be considered.
15.
The following
statement(s) is/are true concerning the epidemiology of inguinal hernias.
a.
Inguinal hernias
occur with a male-to-female ratio of about 7:1
b.
Femoral and
umbilical hernias are more common in women, with a female-to-male ratio of 4:1
c.
The frequency of
inguinal hernias increases with age
d.
Almost all
umbilical hernias occur in the pediatric age group
Answer: a,
c
Inguinal
hernias are the most frequently occurring hernia by a factor of five over other
individual types. Umbilical hernias constitute about 14% of hernias, femoral
hernias about 5%, and other types are rare. There is a male prevalence in
inguinal hernias of about 7:1 (male-to-female), whereas there is a female
dominance in femoral and umbilical hernias of 8:1 and 7:1 (female-to-male),
respectively. For inguinal hernia, which occurs at all age levels, frequency
increases with age. Umbilical hernias have a bimodal distribution, peaking in
the pediatric population and then in the 40 to 60 year group, in which the
hernias are principally paraumbilical.
16.
A 77-year-old
multiparous female presents with a bowel obstruction. She has no previous
abdominal operations and no abdominal wall hernias can be detected. In addition
to her abdominal symptoms, she reports pain in her right medial thigh. The
following statement(s) is/are true concerning her diagnosis and management.
a.
Expectant
management with nasogastric suction and IV fluid replacement is indicated
b.
A right groin
approach is indicated for exploration and repair of the presumed hernia
c.
The use of a
polypropylene mesh will likely be necessary for repair
d.
A correct
diagnosis can usually be made by visualizing an external mass in the upper,
medial thigh
Answer: c
An
obturator hernia is a hernia that occurs through the obturator canal,
accompanied by the obturator vessels and the obturator nerve. Although rare,
most obturator hernias occur in older multiparous women and are predominantly
right-sided. Symptoms are frequently intermittent but tend to be acute and
become increasingly severe with incarceration of the hernia. Intestinal symptoms
predominate, but dysesthesia or pain in the medial thigh with occasional
radiation to the hip is often present. Dysesthesia results from compression of
either division of the obturator nerve. Although the hernia is never externally
visible, in a small percentage of patients a mass can be palpated in the upper,
medial thigh. A correct diagnosis of obturator hernia is made in only about
one-third of patients presenting with intestinal obstruction. Plain radiographs
are seldom helpful, however a CT scan will usually confirm the diagnosis.
Treatment is operative. There is no place for expectant therapy, especially in
a patient with pain an parasthesias along the inner aspect of the thigh or with
clinical or radiographic evidence of bowel obstruction. Many surgical
approaches have been promoted, but the transabdominal approach should be used
because it has several advantages. It best confirms the diagnosis and exposes
the obturator canal, orifice, vessels, and nerve, also permitting bowel
resection when required. The sac is dealt with in a standard fashion. The
hernia defect should be repaired, but repair usually requires a polypropylene
mesh patch because the margin of the defect cannot be approximated primarily.
17.
The following
statement(s) is/are true concerning umbilical hernias in adults.
a.
Most umbilical
hernias in adults are the result of a congenital defect carried into adulthood
b.
A paraumbilical
hernia typically occurs in multiparous females
c.
The presence of
ascites is a contraindication to elective umbilical hernia repair.
d.
Incarceration is
uncommon with umbilical hernias
Answer: b
An
umbilical hernia in a child is usually considered to be congenital. Only about
10% of umbilical hernias in adults are thought to be the result of a congenital
defect carried into adulthood. Most adult umbilical hernias are acquired and
are called paraumbilical hernias. The paraumbilical hernia typically occurs in
a multiparous female. Other patients with increased intraabdominal pressure,
particularly with concomitant chronic abdominal distension as from ascites, are
also at increased risk for the development of paraumbilical hernias. Umbilical
and paraumbilical hernias vary from small to extremely large. Incarceration is
frequent in the large hernias, which typically have a small neck.
Indications
for umbilical hernia repair in adults include symptoms, incarceration, large
hernia relative to the neck, and trophic changes in the overlying skin. Among
adults with associated ascites, repair is advocated to avoid potentially serious
complications. The presence of discoloration or ulceration of overlying skin or
a rapid increase in size of the hernia herald impending rupture. Spontaneous
rupture of the hernia in these patients can be catastrophic and is frequently
associated with mortality rates approaching 30%. By comparison, elective
umbilical hernia repair can be performed safely in patients with ascites with
acceptable morbidity and mortality.
18.
Retroperitoneal
fibrosis is a fibrosing condition of retroperitoneum, which is of significance
as it generally encompasses the ureters and eventually causes hydronephrosis
and kidney damage. Which of the following statement(s) is/are true concerning
this condition?
a.
The majority of
cases are idiopathic in nature
b.
A history of use
of methysergide for treatment of migraine headaches would be significant
c.
There is no known
association of malignancy with retroperitoneal fibrosis
d.
The disease
occurs more commonly in women than in men
Answer: a,
b
Retroperitoneal
fibrosis is a rare condition in which fibrosis develops in the retroperitoneal
space. The ureters frequently will become encompassed by the process eventually
causing hydronephrosis and kidney damage. Retroperitoneal fibrosis occurs most
commonly in the fifth and sixth decades with a 2:1 male-female predominance.
The pathophysiology of retroperitoneal fibrosis remains to be delineated. In
fully two-thirds of cases, retroperitoneal fibrosis is idiopathic, however, an
autoimmune process has been suggested as a potential cause. About 12% of cases
of retroperitoneal fibrosis have been associated with the use of methysergide,
a serotonin agonist used for vascular and migraine headache, and in this
subgroup females outnumber males 2:1. Primary or metastatic malignancy in the
retroperitoneum is found in 8% of patients with retroperitoneal fibrosis.
Sarcomas are the most common primary tumors, but non-Hodgkin and Hodgkin
lymphomas and ureteral cancer have also been found. Metastases have originated
from cancer of the stomach, breast, colon, carcinoid, pancreas, prostate,
ovary, and cervix. The focus of tumor may be small but may induce desmoplasia
that is grossly indistinguishable from benign variance of retroperitoneal
fibrosis.
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