Добавил:
Sekretar
kiopkiopkiop18@yandex.ru
t.me/Prokururor I Вовсе не секретарь, но почту проверяю
Опубликованный материал нарушает ваши авторские права? Сообщите нам.
Вуз:
Предмет:
Файл:Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_3742_Библиотеки_им_академика_М_И_Перельмана
.pdf
290 Section 13: Venous Disease
operation should be repaired by lateral venorrhaphy and interposition graft if there is more than
30%–40% loss of circumference of the iliac vein. Patients should be monitored for deep venous
thrombosis in the perioperative period. Major venous injury may occur during aortoiliac reconstruction, oncologic pelvic operations, and anterior lumbar spine surgery. Emergent vascular
consultation is recommended for management of such serious injuries.
Correct Answer B Left iliac vein occlusion
Reference
Hans, S. S., Vang, S., & Sachwani-Daswani, G. (2018). Iatrogenic major venous injur y is associated with
increased morbidity of aortic reconstruction. Ann Vasc Surg, 47, 200–204. PMID: 28887236.
50. RATIONALE
Portal vein thrombosis is a known complication of cirrhosis of the liver with portal hypertension and hypersplenism. Acute portal/superior mesenteric vein thrombosis will result in intestinal venous congestion, resulting in intermittent or continuous abdominal pain and diarrhea.
Chronic portal vein thrombosis most often is asymptomatic. Portal vein thrombus is not an
indication for splenectomy, liver transplant, or distal splenorenal shunt. Anticoagulation helps
in recanalization of the portal vein with improved survival.
Correct Answer C Anticoagulation
Reference
Kinjo, N., Kawanaka, H., Akahoshi, T., et al. (2014). Portal vein thrombosis in liver cirrhosis. World J
Hepatol, 6(2), 64–71. PMID: 24575165
51. RATIONALE
The Caprini model of risk stratification for venous thromboembolism has been validated in
a NSQIP study involving more than 8000 elective surgical procedures. Risk factors are scored
from 1 to 5 points with stroke (less than 1 month), knee or hip arthroplasty, hip, pelvis, leg
fracture, and spinal cord injury (less than 1 month) representing 5 points. A total risk score of 1
or less (low risk) means the incidence of deep venous thrombosis is 2%; a total risk score of 5 or
more is the highest risk, with incidence of deep venous thrombosis as high as 40%–80% with up
to 5% mortality. The use of this model to identify and grade the risk of venous thromboembolism aids in selecting suitable prophylaxis for venous thromboembolism.
Correct Answer D Acute spinal cord injury
Reference
Caprini, J. A. (2010). Risk assessment as a guide for the prevention of the many faces of venous throm-
boembolism. Am J Surg, 199(1 Suppl), S3–10. PMID: 20103082
52. RATIONALE
Venous ulcer is a common condition, and its incidence increases with advanced age and in
women. The ulcers are typically located just above the ankle on the medial side (occasionally
on the lateral side) and are usually superficial. In a systemic review of 48 randomized controlled
trials comparing compression dressings with no compression, compression dressings with
Section 13: Venous Disease 291
Данная книга находится в списке для перевода на русский язык сайта https://meduniver.com/
multiple layers of elastic components were the most effective treatment method of increasing
healing of the venous ulcers, unless the ulcer is infected with associated cellulitis and drainage
causing significant discomfort. When the associated cellulitis is present, cultures and appropriate antibiotics should be administered depending on the sensitivity results. Routine use of
antibiotics without any clinical evidence of infection in the ulcers is not indicated. If the venous
ulcer does not respond to conservative treatment, venous reflux study should be performed
to detect any perforator or greater saphenous vein incompetence, which may be amenable to
endovenous ablation or sclerotherapy. Though uncommon, iliocaval venous obstruction should
be ruled out in patients who do not have a superficial or deep venous ref lux in the femoral, popliteal, and tibial veins or perforator veins. The mere existence of either reflux or obstruction does
not appear to be the complete pathology for venous ulcers, as activation of the inflammatory
cascade may act as an inciting factor for the appearance of ulceration. In some cases, healing
is impaired due to concomitant arterial obstruction, local trauma, lymphedema, autoimmune
disease, and superimposed infection.
Correct Answer C Graduated compression stockings with local wound care and management of dermatitis
Reference
O’Donnel l, T. F., Jr, Passman, M. A., Marston, W. A., et al. (2014). Management of venous leg ulcers: clin-
ical practice guidelines of the Society for Vascular Surgery ® and the American Venous Forum.
J Vasc Surg, 60(2 Suppl), 3S–59S. PMID: 24974070.
MCQs 1–19
SECTION 14: LYMPHOLOGY
Q1. Female-to-male ratio in primary lymph-
edema is:
A. 2.5 to 1
B. 3.5 to 1
C. 4.5 to 1
D. 5.5 to 1
Q2. The most common form of lymphedema
in developed countries is:
A. Congenital (Milroy disease)
B. Lymphedema praecox (Meigs disease)
C. Lymphedema tarda
D. Acquired lymphedema
Q3. Clinically significant edema of the upper
extremity after axillary intervention in
breast cancer survivors occurs in:
A. <6% of patients
B. 6%–30% of patients
C. 31%–35% of patients
D. 36%–40% of patients
Q4. In primary lymphedema, obstruction of
proximal lymphatics or nodes with an
absence of distal lymphatic involvement
occurs in:
A. 20% of cases
B. 30% of cases
C. 40% of cases
D. 50% or more of cases
Q5. Staging of chronic lymphedema is based
on:
A. Biopsy of subcutaneous tissue
B. Clinical exam
C. Lymphoscintigraphy
D. MRI
Q6. The following signs are associated
with the diagnosis of lymphedema
except:
A. Peau d’orange
B. Kaposi–Stemmer sign
C. Buffalo hump
D. Homans sign
Q7. The most common complication of
lymphedema is:
A. Elephantiasis nostras verrucosa
B. Immunodeficiency and malnutrition
C. Infection
D. Malignant tumors
Q8. The incidence of post-mastectomy angio-
sarcoma (Stewart–Treves syndrome) varies from:
A. Less than 0.07%
B. 0.07%–0.45%
C. 0.46%–1%
D. 1.1%–1.5%
Q9. The 5-year survival of Stewart–Treves
syndrome is:
A. 3%–8.4%
B. 8.5%–13.6%
C. 13.7%–15%
D. 15.1%–18%
Q10. Tropical lymphedema is most often
caused by:
A. Podoconiosis
B. Lymphatic filariasis
C. Filamentous bacteria or true fungus
causing mycetoma
D. Extensive burns of the extremity
DOI: 10.1201/9781003389897-14
Section 14: Lymphology 293
Данная книга находится в списке для перевода на русский язык сайта https://meduniver.com/
Q11. Podoconiosis (mossy foot) is caused by:
A. True fungi (eumycetoma)
B. Filamentous bacteria (actinomycetoma)
C. Absorption of mineral microparticles into
the soles of the bare foot exposed to red
clay soil derived from alkalinic volcanic
rock
D. CLOVES syndrome
Q12. For objective documentation of lymphatic
dysfunction, the best study is:
A. Direct lymphography
B. Near-infrared fluorescent imaging
C. Magnetic resonance imaging
D. Isotopic lymphoscintigraphy
Q13. Typical abnormalities observed in lymph-
edema using isotopic lymphoscintigraphy
include:
A. Dermal backflow and crossover filling
with retrograde backflow
B. Absent or delayed transport of tracer
C. Delayed or absent visualization of lymph
nodes
D. Dermal backflow, crossover filling and
retrograde backflow, delayed or absent
transport of tracer, delayed or absent
visualization of lymph nodes
Q14. The advanced imaging modality of choice
for diagnosis and management of lymphedema is:
A. CT
B. MRI
C. PET/MR lymphography
D. Ultrasound
Q15. Lifestyle changes for the management of
early stage of lymphedema include:
A. Daily hygiene and skin care
B. Weight loss
C. Aerobic exercises
D. Daily hygiene and skin care, weight loss,
and aerobic exercises
Q17. The goals of compression therapy for
management of lymphedema include:
A. Improvement of the lymphatic flow and
venous return
B. Reduction of the accumulated protein
debris and sustained volume control
C. Maintenance of skin integrity and protec-
tion of the limb from potential trauma
D. Improvement of the lymphatic flow
and venous return, reduction of accumulated protein debris and decreased
volume, and maintenance of skin
integrity
Q18. Surgical approaches for lymphedema are
best reflected by which statement:
A. Physiologic procedures such as micro-
scopic lymphovenous anastomosis (LVA)
and vascularized lymph node transfer
(VLNT) are effective only in later stages of
lymphedema
B. Debulking procedures or reductive pro-
cedures are useful in the early stages of
lymphedema
C. Conservative therapy can be
stopped after surgical approaches to
lymphedema
D. LVA and VLNT are effective in early
stages of lymphedema and debulking procedures in the later stages,
with a combination of conservative
therapy immediately after any surgical
procedure
Q19. Debulking procedures for more advanced
stages of lymphedema include all of the
following except:
A. Liposuction
B. Charles procedure
C. Sistrunk procedure
D. Groin lymph node dissection
Q16. Complex decongestive therapy should be
the first line of treatment for which stage
of lymphedema:
A. Stage II lymphedema
B. Stage III lymphedema
C. Stage I lymphedema
D. Stage II and III lymphedema
294 Section 14: Lymphology
RATIONALE 1–19
1. RATIONALE
Of 125 patients treated at the Mayo Clinic, 97 (78%) were women and 28 (22%) were men, with
a higher ratio in women of 3.5 to 1. The ratio of unilateral to bilateral lymphedema was 3 to 1.
Lymphedema primarily affects girls near menarche. Primary lymphedema affects 1 of every
6000–10,000 live births and is present in 1.15 per 100,000 people under 20 years of age. The
inf luence of estrogen and inflammation are thought to be important etiological factors in
primary lymphedema. In congenital lymphedema, skin is roughened; becomes hyperkeratotic;
and develops verrucous cobblestone-like papules, plaques, and nodules with woody fibrosis.
Subcutaneous tissue is filled with watery fluid and abundant fat lobules. The deep tissues and
muscles are never affected by primary lymphedema.
Correct Answer B 3.5 to 1
Reference
Smeltzer, D. M., Stickler, G. B., & Schirger, A. (1985). Primary lymphedema in children and adoles-
cents: a follow-up study and review. Pediatrics, 76(2), 206–218. PMID: 4022694
2. RATIONALE
Lymphedema can be primary or secondary. Primary lymphedema results from a developmental
abnormality, lack of an offending injury, and often with a positive family history. This form of
lymphedema may present at birth, during adolescence, or later in life. Primary lymphedema
can be further subdivided into congenital lymphedema, lymphedema praecox, and lymphedema tarda. Congenital lymphedema or Milroy disease (10%–25% of primary lymphedema)
manifests within the first 2 years of life. It usually affects women (2 to 1 female-to-male ratio), is
bilateral, and involves a lower extremity. It is usually not progressive and may improve spontaneously over time. It is associated with the FLT4 gene and is autosomal dominant. Lymphedema
praecox (Meigs disease) constitutes 65%–85% of primary lymphedema and most commonly
manifests at puberty but may appear any time before the age of 35. It predominately affects
women (4 to 1 female-to-male ratio), is unilateral, and involves the lower extremities. The
associated gene is FOXC02, and inheritance is autosomal dominant. Lymphedema tarda (10%
of primary lymphedema) appears after the age of 35 years. Secondary lymphedema is the most
common form of lymphedema encountered in the United States.
Correct Answer D Acquired lymphedema
Reference
Smeltzer, D. M., Stickler, G. B., & Schirger, A. (1985). Primary lymphedema in children and adoles-
cents: a follow-up study and review. Pediatrics, 76(2), 206–218. PMID: 4022694
3. RATIONALE
The secondary (acquired) form of lymphedema is the most common form of lymphatic obstruction. In the United States, iatrogenic causes are predominant among the acquired form of lymphedema. Lymphatic trauma following surgery or radiation therapy for cancer is the next leading
cause of acquired lymphedema. According to recent estimates 6%–30% of breast cancer survivors
who have undergone axillary node dissection experience clinically significant lymphedema. The
advent of sentinel lymph node biopsy has decreased the incidence to 5%–7%. Adjuvant radiation
Section 14: Lymphology 295
Данная книга находится в списке для перевода на русский язык сайта https://meduniver.com/
therapy for local treatment of nodal disease can lead to upper or lower extremity lymphedema.
Other factors such as trauma, infection, and obesity contribute to secondary lymphedema.
Worldwide the most common cause of secondary lymphedema is infection by the microfilaria
Wuchereria bancrofti, which is transmitted by various mosquito vectors. Adult filarial worms
reside in and obstruct lymphatic channels causing irreversible scarring and fibrosis and resulting in massive edema. Eosinophilia is present in peripheral blood smear and microfilaria can
be demonstrated in peripheral nocturnal blood, centrifuged urine sediment, or lymphatic fluid.
Other types of lymphatic vascular trauma include burns and larger circumferential wounds to the
extremity. Other causes of acquired lymphedema include bacterial or fungal infection, infection
after snake or insect bites, pregnancy, contact dermatitis, and rheumatoid arthritis.
Correct Answer
B 6%–30% of patients
Reference
Brayton, K. M., Hirsch, A. T., O’Brien, PJ. (2014). Lymphedema prevalence and treatment benefits in
cancer: impact of a therapeutic intervention on health outcomes and costs. PLoS ONE, 9(12),
e114597. PMID: 25470383
4. RATIONALE
It has been suggested that a morphological classification of primary lymphedema provides
more useful information in regard to prognosis than classification by age at onset. This classification relies on an anatomical description of the lymphatic vasculature.
Aplasia – no lymphatic vessels can be identified
A.
B. Hypoplasia – a diminished number of lymphatic vessels
C. Numerical hyperplasia – an increased number of lymphatic vessels
D. Hyperplasia – in addition to an increase in number, the vessels have valvular incompetence
and display tortuosity and dilatation (mega lymphatics, lymphangiectasia)
Mega lymphatics and lymphatic hyperplasia are less common than hypoplasia or aplasia. These
patients often have unilateral edema involving the entire lower extremity. Mega lymphatics are
associated with a greater extent of involvement and a worse prognosis. Aplasia and hypoplasia
have a different natural history depending on whether they involve the distal or proximal portion of the leg. Distal obstruction – approximately one-third of all cases – results from agenesis,
hypoplasia, or obstruction of the distal lymphatic vessels with relatively normal proximal vessels. In these cases, the swelling is usually bilateral and mild, and women are affected much
more frequently than men. The prognosis is good. Familial occurrence, female preponderance,
and indolent progression characterize this pattern of lymphatic disturbance. Proximal obstruction occurs in more than half of the cases and involves obstruction of the proximal lymphatics
or nodes with an absence of distal lymphatic involvement. Pathologic findings reveal intranodal
fibrosis. The finding is unilateral and severe with a slight female preponderance. Because of
progression with associated severe abnormality, patients may require surgical intervention if
there is isolated obstructive hypoplasia with worsening of the edema of the entire limb.
Correct Answer D 50% or more of cases
Reference
Rockson, S. G. (2003). Syndromic lymphedema: keys to the kingdom of lymphatic structure and func-
tion? Lymphat Res Biol, 1(3), 181–183. PMID:19642940
296 Section 14: Lymphology
5. RATIONALE
The 10th International Society of Lymphology suggests staging of chronic lymphedema regardless of cause into four stages (grades) and subclassified as mild, moderate, or severe based on
clinical examination.
• Stage 0 – Latent phase: Excessive fluid accumulates and fibrosis develops around the lymphatics, but no edema is apparent clinically with only mild discomfort
• Stage 1 – Swelling relieved by elevation, including pitting edema, with no clinical evidence of
fibrosis
• Stage 2 – Swelling not relieved by limb elevation, moderate to severe fibrosis
• Stage 3 – Irreversible edema caused by repeated bouts of inflammation, fibrosis, and sclerosis
of skin and subcutaneous tissue, also called lymphostatic elephantiasis
This classification allows for the evaluation of treatment effectiveness and the comparison of
different treatment modalities. The drawback is that in some cases staging based on clinical
examination may be difficult without a biopsy of the subcutaneous tissue.
Correct Answer B Clinical exam
Reference
Greene, A. K., & Goss, J. A. (2018). Diagnosis a nd staging of lymphedema. Semin Plast Surg, 32(1), 12–16.
PMID: 29636648
6. RATIONALE
Lower extremity lymphedema occurs as the interstitial space is expanded by an excess
accumulation of protein-rich fluid and usually manifests as swelling in the dorsal surface of
the foot with a characteristic blunt “squared-off” appearance of digits of the lower extremity. Initially there is preferential swelling of the distal extremity and there is progression
proximally. Pitted or dimpled texture of the skin (peau d’orange) and the Kaposi–Stemmer
sign (an inability to pinch the fold of the skin on the dorsal aspect of the base of the second
toe) are characteristics of lymphedema. The dorsum of the forefoot is often involved, giving
a typical appearance of a “buffalo hump.” In advanced stages the skin over the affected area
becomes hyperkeratotic and develops verrucous cobblestone-like papules, plaques, and
nodules with underlying woody fibrosis. Primary lymphedema may be associated with yellow discoloration of the nails. Intense pain is rare, although heaviness or aching of a limb
is a frequent complaint. If a patient with lymphedema complains of marked pain, infection,
or neurotic pain in the area, scar tissue should be suspected. Unlike the skin changes in
venostasis, lymphedema patients maintain a high degree of hydration and elasticity, and
ischemic changes due to high skin tension and disruption of the circulation to the skin and
subcutaneous tissue are rare. Homans sign is associated with deep venous thrombosis in
the calf.
Correct Answer D Homans sign
Reference
Grada, A. A., & Phillips, T. J. (2017). Lymphedema: diagnostic workup and management. J Am Acad
Dermatol, 77(6), 995–1006. PMID: 29132859
Section 14: Lymphology 297
Данная книга находится в списке для перевода на русский язык сайта https://meduniver.com/
7. RATIONALE
Recurrent soft tissue infection is one of the most common and difficult aspects of long-standing
lymphedema. Accumulated f luid and proteins provide a good substrate for bacterial growth.
Lymphatic dysfunction impairs local immune responses, which plays a permissive role in the
propagation of bacterial and fungal invasion. With recurrent infection, there is progressive
damage of lymphatic capillaries, and a reported infection rate of up to 31% has been reported.
Recurrent episodes of cellulitis can damage the existing percutaneous lymphatics, exacerbate
the skin disease, and worsen the edema. Lymphangiectasia with protein-losing enteropathy
may result in loss of proteins, long-chain triglycerides, cholesterol, and calcium. Loss of cytokines and lymphocytes may result in immunodeficiency. In rare cases, chronic lymphedema
may be complicated by development of lymphangiosarcoma, which manifests as multicentric lesions with bluish nodules and sclerotic plaques. The other malignant tumors, including
Kaposi sarcoma, squamous cell carcinoma, and malignant lymphoma and melanoma, may
occur.
Correct Answer
C Infection
Reference
Burian, E. A., Karlsmark, T., Franks, P. J., et al. (2021). Cellulitis in chronic oedema of the lower leg: an
international cross-sectional study. Br J Dermatol, 185(1), 110–118. PMID: 33405247
8. RATIONALE
Long-standing chronic lymphedema may result in deadly cutaneous angiosarcoma, also known
as Stewart–Treves syndrome (STS), which is classically associated with radical mastectomy.
However, STS can be associated with any long-standing primary or secondary lymphedema.
The incidence of post-mastectomy STS of the arm varies from 0.07% to 0.45%. It manifests as
painless, reddish-purple skin nodules that gradually increase in size and number. The primary
lesion tends to form satellite lesions and telangiectasia. The tumor cells have a predilection for
local ulceration and pulmonary metastasis via the hematogenous route. The diagnosis is often
delayed.
Correct Answer B 0.07%–0.45%
Reference
Sharma, A., & Schwartz, R. A. (2012). Stewart–Treves syndrome: pathogenesis and management. J Am
Acad Dermatol, 67(6), 1342–1348. PMID: 22682884
9. RATIONALE
An extensive investigation in the form of CT scan of the chest and abdomen and PET scan
should be performed to determine the extent of metastatic disease and whether an aggressive treatment program is justified for the management of Stewart–Treves syndrome. The most
common treatment is a limb disarticulation or forequarter amputation. When discovered early,
however, a combination of radiation therapy and chemotherapy can help, resulting in temporary remission. The 5-year survival rate ranges from 8.5% to 13.6%. The median survival of STS
patients is approximately 19 months after diagnosis. Prognosis is poor; therefore, multiple deep
biopsy specimens of suspicious lesions in the affected extremity should be obtained and examined at the earliest.
298 Section 14: Lymphology
Correct Answer B 8.5%–13.6%
Reference
Schiffman, S., & Berger, A. (2007). Stewart–Treves syndrome. J Am Coll Surg, 204(2), 328. PMID:
172 54938
10. RATIONALE
There are two main causes of tropical lymphedema. The most common cause is lymphatic
filariasis, commonly known as elephantiasis, which is caused by infestation with the parasitic
nematode Wuchereria bancrofti (and in Asia by Brugia malayi and B. timori) transmitted by
mosquitoes as vectors. The second main cause is podoconiosis. Manifestations of acute filariasis include lymphangitis and orchitis. Chronic filariasis causes lymphedema with associated
skin changes. If filariasis is suspected, a blood smear should be collected at night (between
11 PM and 3 AM stained with Giemsa or hematoxylin-eosin stain to look for microfilaria under
the microscope). In the United States, filariasis has been reported in Hawaii. For active filariasis, diethylcarbamazine (DEC) is the treatment of choice.
Correct Answer B Lymphatic filariasis
Reference
Molyneux, D. H. (2012). Tropical lymphedemas – control and prevention. N Engl J Med, 366(13),
1169–1171. PMID: 22455411
11. RATIONALE
Podoconiosis, also known as “mossy foot,” is the second main cause of tropical lymphedema.
It is an endemic non-filarial elephantiasis caused by the absorption of mineral microparticles
in the soles of bare feet exposed to red clay soil derived from alkalinic volcanic rock. It has a
genetic predisposition in the HLA class 11 region. This condition causes chronic lymphedema
and usually manifests as bilateral swelling and disfigurement of the feet and legs. Treatment
consists of avoidance of prolonged contact between the skin and the irritant soils by wearing
robust footwear, avoiding exposure to the irritant soil, or by change in occupation. Maintaining
foot hygiene through daily washing with soap and water or antiseptics is recommended. Using
compression bandages and limb elevation above the level of the hip can both help promote
venous and lymphatic return and reduce swelling.
Mycetoma is an uncommon chronic infection of the skin and subcutaneous tissues of the foot
usually seen in tropical countries and is caused by true fungi (eumycetoma) or filamentous
bacteria (actinomycetoma). The disease is characterized by the triad of tumefaction, draining
sinuses, and presence of colonial grains in the exudates. CLOVES syndrome is characterized
by congenital lipomatous overgrowth, vascular malformations, epidermal nevi, and skeletal
anomalies. Skeletal abnormalities such as enlarged bony structure of the legs with superficial
phlebectasia and capillary malformations are also present.
Correct Answer C Absorption of mineral microparticles into the soles of the bare foot
exposed to red clay soil derived from alkalinic volcanic rock
Reference
Davey, G., Tekola, F., & Newport, M. J. (2007). Podoconiosis: non-infect ious geochemical elephantiasis.
Trans R Soc Trop Med Hyg, 101(12), 1175–1180. PMID: 17976670
Section 14: Lymphology 299
Данная книга находится в списке для перевода на русский язык сайта https://meduniver.com/
12. RATIONALE
Isotopic lymphoscintigraphy is an accurate and reproduceable method for confirming the diagnosis of lymphedema. It involves the injection of a filtered colloid, technetium 99, subdermally
within one of the interdigital spaces of the affected limb. The lymphatic transport of the radiolabeled macromolecule is tracked with a gamma camera, thus providing a semi-quantifiable
assessment of major lymphatic trunks and lymph nodes. The normal study shows several lymph
vessels as the tracer is visualized along the anteromedial aspect of the leg. Many lymph channels in the calf may be identifiable. But lymph channels run close to each other, and separate
activity in each larger channel is usually not visualized. Tracer activity clears in the groin lymph
nodes in the range of 15–60 minutes. The qualitative interpretation of images shows moderate
sensitivity and excellent specificity of the diagnosis of lymphedema. Quantitative lymphoscintigraphy may improve detection of early disease but cannot reliably distinguish primary from
secondary lymphedema.
Correct Answer D Isotopic lymphoscintigraphy
Reference
Szuba, A., Shin, W. S., Strauss, H. W., & Rockson, S. (2003). The third circulation: radionuclide lympho-
scintigraphy in the evaluation of lymphedema. J Nucl Med, 44(1), 43–57. PMID: 12515876
13. RATIONALE
Typical abnormalities using isotopic lymphoscintigraphy include delayed or absent dermal
backflow, absent or delayed transport of tracer, crossover filling with retrograde backf low, and
either absent or delayed visualization of lymph nodes. Dermal backflow suggests the presence
of lymphatic hypertension and valvular incompetence. In most patients with primary lymphedema, lymph channels are either absent or obliterated, and occasionally they may be incompetent and ectatic. The delayed appearance or asymmetrical appearance of radiocontrast material
in the proximal nodal tissue can be useful to semi-quantitatively measure the severity of
lymphatic insufficiency. The density of subcutaneous accumulation of radiotracer as a marker
of dermal backflow can also be quantified. The ratio of radioactivity in ipsilateral versus contralateral nodal tissue can also be quantified in a patient with unilateral limb edema. Quantitation
is of great value in predicating successful response to therapeutic intervention. The findings in
lymphangiectasia consist of dilated lymph channels with virtually no delay in lymph transport.
Correct Answer D Dermal backflow, crossover filling and retrograde backflow, delayed or
absent transport of tracer, and delayed or absent visualization of lymph nodes
Reference
Cambria, R. A., Gloviczki, P., Naessens, J. M., & Wahner, H. W. (1993). Noninvasive evaluation of the
lymphatic system with lymphoscintigraphy: a prospective, semiquantitative analysis in 386
extremities. J Vasc Surg, 18(5), 773–782. PMID: 8230563
14. RATIONALE
Lymphedema is typically confined to the epifascial space of the skin and subcutaneous tissue, sparing muscle. With CT or MRI imaging, a characteristic honeycomb distribution of
edema within the epifascial structures, with thickening of the skin is seen. In edema due to
other causes, both epifascial and subfascial compartments are affected. In lipedema there is
fat accumulation without fluid. MRI also helps in identification of lymph nodes and enlarged
Соседние файлы в папке Библиотека им академика М.И. Перельмана