Appendiceal Ascariasis in Children

Ann Saudi Med. 2010 Jan-Feb; 30(1): 63–66.

Appendiceal Ascariasis in Children

Imtiaz Wani,  Muddasir Maqbool, Abid Amin, Firdous Shah, Arshad Keema, Jang Singh, Maki Kitagawa, and Mir Nazir

BACKGROUND:

The propensity of Ascaris lumbricoides to wander leads to varied surgical complications in the abdomen. Wandering A lumbricoides may sometimes reach the vermiform appendix and its presence there may remain silent or incite pathology. Our aim was to study ascariadial appendicitis.

METHODS:

Over a period of 3 years, we identified children who were found to have appendiceal ascariasis during surgery for different intestinal complications due to ascariasis. We studied the relationship between ascariasis and its lodgement inside the vermiform appendix in these patients. No preoperative diagnosis was made in this series.

RESULTS:

We found 11 patients with appendiceal ascariasis. It was incidentally found that 8/11 (72.7%) patients had worms inside their vermiform appendix but not appendicitis, whereas the remaining three patients (27.2%) were found to have Ascaris-associated appendicitis. The characteristic finding in Ascaris-infested vermiform appendix was that the worm is positioned with its head at the base and its tail at the tip of the appendix.

DISCUSSION

Surgical manifestations of abdominal ascariasis are varied and are attributed to the wandering nature of Ascaris lumbricoides. The preoperative diagnosis of this condition continues to remain difficult, although the parasite can sometimes be observed inside the lumen during micropathological examination. Appendicitis due to the migration of Ascaris lumbrocoides into the appendix is still debatable because the symptoms of this migration may simulate appendicitis, but rarely cause it.^3,4 The hypothesis that Ascaris lumbricoides is a major cause of appendicitis in children has been disproved.⁵

In Ascaris infestations associated with a normal appendix, Ascaris lodges in the appendix and comes and goes on its own accounting for the intermittent pain observed sometimes in children with high worm load. During the kneading of the worms, this high intestinal worm load coupled with a competent illeaocecal valve can sometimes provide a high load of worms in the cecum. This leads to the entry of the worms into the lumen of the appendix to escape the kneading. A competent ileocecal valve prevents the worms from escaping through the retrograde route. An incompetent ileocecal valve with proximal worm bolus obstruction may force the worm to travel again towards the cecum. This further contributes to the worm load in the cecum and in an attempt to seek natural orifices, the worms may enter the vermiform appendix. This type of Ascaris-associated normal appendix occurs in the wide-lumen, free-lying appendix. More than one worm can be seen in the lumen even when there are no grossly or microscopically visible features of appendicitis. An inflamed appendix can contain worms inside its lumen although it is debatable whether the worms caused the inflammation or whether they migrated to an already inflamed appendix. However, the presence of live worms and the associated pathology of the appendix do not favor the hypothesis that the worms cause appendicitis. Also, the presence of Ascaris inside the inflamed appendix favors the hypothesis that Ascaris has an affinity for pathological tissue. The wandering nature of Ascaris lumbricodes makes these worms seek openings just as they do in the perforated appendix wherein they reach the perforation site and lodge freely in the peritoneal cavity.

One of the characteristic findings of this study was that the worms were seen in the appendix with their heads at the base and their tail ends at the tip end of the appendix, which might lead to the frequent escape of worms from the appendix. Ascaris can be removed through the distal tip of the appendix when more than one worm is seen inside the appendix. It is to be stressed that complete removal of worms from the appendix is to be done when only a portion of the worm is lying inside the appendix and part of it is inside the cecum to avoid necrosis of the portion inside the appendicular stump, which may lead to fecal fistula. Our observations support the direct evidence of the presence of Ascaris in the vermiform appendix in contrast to reports of indirect evidence of migration of the worms into the appendix due to the presence of Ascaris lumbricoides eggs lodged in the appendix without any features of appendicitis.⁶

CONCLUSION:

Migration of A lumbrocoides inside the vermiform appendix is an incidental finding and tends to pursue a silent course in most patients. Only rarely does the presence of Ascaris inside the vermiform appendix cause appendicitis.

Ascaris lumbricoides is rarely seen in the vermiform appendix although they are seen in the intestines of individuals in tropical countries. Ascaris-associated appendicitis is a form of wandering ascariasis and is usually the sequelae of a high intestinal worm load.^1,2 Ascaris can be found in the normal appendix but may also be associated with appendicitis. We studied the clinical and pathological sequelae of the migration of Ascaris to the appendix.

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BẢN LUẬN

Biểu hiện ngoại khoa của nhiễm giun đũa trong bụng rất đa dạng và được gán cho bản chất lang thang của giun đũa Ascaris lumbricoides. Các chẩn đoán trước mổ của tình trạng này vẫn còn khó khăn, mặc dù đôi khi có thể thấy ký sinh trùng bên trong lòng ruột trong khảo sát vi mô bệnh học. Viêm ruột thừa do sự di cư của giun đũa vào ruột thừa vẫn còn gây tranh cãi bởi vì các triệu chứng của sự di cư này có thể kích thích làm viêm ruột thừa, nhưng hiếm khi gây ra. Giả thuyết cho rằng giun đũa Ascaris lumbricoides là nguyên nhân chính của viêm ruột thừa ở trẻ em đã được chứng minh là sai.

Trong trường hợp giun đũa tràn ngập với ruột thừa bình thường, giun đũa trú ngụ trong ruột thừa và đến rồi đi, giải thích cho cơn đau từng hồi đôi khi gặp ở trẻ em nhiễm nhiều giun. Trong quá trình ruột nhào trộn, những con giun này cùng với van hồi manh tràng có tác dụng đôi khi có thể cho nhiều giun vào trong manh tràng. Điều này dẫn đến sự xâm nhập của giun vào lòng ruột thừa để thoát khỏi nhào trộn. Van hồi manh tràng có tác dụng ngăn chặn giun trốn thoát ra ngoài theo đường ngược lại. Khi van hồi manh tràng không đủ năng lực với búi giun tắc nghẽn gần đó có thể buộc giun lại đi tới manh tràng lần nữa. Điều này góp phần tải giun trong manh tràng và trong nỗ lực tìm kiếm các lỗ tự nhiên, giun có thể chui vào ruột thừa. Trường hợp này là của giun đũa với ruột thừa bình thường xảy ra trong ruột thừa rộng lòng, nằm tự do. Có nhiều hơn một con giun có thể thấy trong lòng ngay khi không có viêm ruột thừa đại thể hoặc vi thể. Một ruột thừa bị viêm có thể chứa nhiều giun trong lòng mặc dù còn tranh cãi xem những con giun này gây ra viêm ruột thừa hoặc là giun di cư đến ruột thừa đã bị viêm từ trước.Tuy nhiên, sự hiện diện của giun còn sống và bệnh lý ruột thừa kết hợp không ủng hộ cho giả thuyết giun gây ra viêm ruột thừa. Ngoài ra, sự hiện diện của giun đũa bên trong ruột thừa bị viêm cũng hỗ trợ cho giả thuyết cho rằng giun đũa có ái lực với bệnh lý mô. Bản chất lang thang của Ascaris lumbricodes làm cho giun đi tìm các lỗ thoát giống như giun đã làm trong thủng ruột thừa, trong đó giun đến các nơi bị thủng và tự do đi vào khoang phúc mạc.

Một trong những phát hiện đặc trưng của nghiên cứu này là giun đã được thấy trong ruột thừa với đầu giun tại gốc của ruột thừa và đuôi giun ở đầu tự do, có thể dẫn đến việc giun đào thoát thường xuyên từ ruột thừa. Giun đũa có thể được bắt ra từ đầu xa của ruột thừa khi có nhiều hơn một con giun được nhìn thấy ở trong ruột thừa. Cần nhấn mạnh rằng chỉ nên loại bỏ hoàn toàn giun từ ruột thừa khi có một phần giun đang nằm trong ruột thừa và phần còn lại bên trong manh tràng để tránh hoại tử phần bên trong khối ruột thừa, điều này có thể gây ra biến chứng rò phân. Quan sát của chúng tôi hỗ trợ cho bằng chứng trực tiếp là hiện diện của giun đũa trong ruột thừa, ngược lại với các báo cáo dựa vào bằng chứng gián tiếp của việc di cư của giun vào ruột thừa là trứng giun đũa có trong ruột thừa mà ruột thừa không bị viêm.

KẾT LUẬN:

Di cư của giun đũa vào trong ruột thừa là một phát hiện ngẫu nhiên và có xu hướng theo một quá trình không có triệu chứng ở hầu hết bệnh nhân. Rất hiếm khi giun đũa  trong ruột thừa gây ra viêm ruột thừa.

Giun đũa hiếm thấy trong ruột thừa mặc dù thấy giun trong ruột bệnh nhân ở các nước nhiệt đới. Giun đũa kết hợp với viêm ruột thừa là một thể bệnh của giun đũa lang thang và thường là hệ quả của tình trạng có nhiều giun trong ruột. Giun đũa có thể được tìm thấy trong ruột thừa bình thường nhưng cũng có thể kết hợp với viêm ruột thừa. Chúng tôi đã nghiên cứu các hệ quả lâm sàng và bệnh lý của sự di cư của giun đũa vào ruột thừa.

Xem thêm về hình ảnh siêu âm của giun đũa trong bài NHÂN CA GIUN CHUI ỐNG MẬT CHỦ tại TRUNG TÂM MEDIC

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WHAT DO YOU THINK ABOUT THE CASE

A 43yo male patient suffers from pain at RLQ for 3 days. Ultrasound detects thickening wall of cecum, and edema of appendix which appeares like an elephant's trunk curved up (Fig.1). And an Ascaris is in the base of the appendix (Fig.2) maybe in going away to the cecum from the appendiceal lumen.

Why did the appendix curve up ?

 

US Images of Asymptomatic Carotid Plaques Predict Stroke

OBJECTIVES: It has been suggested that a juxtaluminal black (hypoechoic) area (JBA) in ultrasonic images of asymptomatic carotid artery plaques is associated with a lipid core close to the lumen or a thrombus on the plaque surface. The aim of our study was to test the hypothesis that the presence and size of JBA predicts future ipsilateral ischemic stroke.


METHODS: JBA was defined as an area of pixels with gray scale value <25 adjacent to the lumen without a visible echogenic cap, after image normalization. The size of a JBA was measured in the carotid plaque images of 1,121 patients with asymptomatic carotid stenosis 50-99% in relation to the bulb (ACSRS study), followed-up for up to 8 years.

RESULTS: JBA had a linear association with future stroke rate. The area under the ROC curve was 0.816. Using Kaplan Meier curves, the mean annual stroke rate was 0.4% in 706 patients with JBA <4 mm2; it was 1.4% in 171 patients with JBA 4-8 mm2, 3.2% in 46 patients with JBA 8-10 mm2 and 5% in 198 patients with JBA >10 mm2 (p<.001). In a Cox model with ipsilateral ischemic events (AF, TIA or stroke) as the dependent variable, JBA (<4, 4-8, >8) was still significant after adjusting for other plaque features known to be associated with increased risk (stenosis, GSM, presence of discrete white areas without acoustic shadowing (DWA) indicating neovascularization, plaque area and history of contralateral TIA or stroke. Plaque area and gray scale median (GSM) were not significant. Using the significant variables (stenosis, DWA, JBA and history of contralateral TIA or stroke), this model predicted the annual risk of stroke (range 0.5-10.0%). The average annual stroke risk was <1% in 734 patients, 1-1.9% in 94, 2-3.9% in 134, 4-5.9% in 125 and 6-10% in 34.

CONCLUSIONS: The size of JBA is linearly related to the risk of stroke and can be used in risk stratification models. These findings need to be confirmed in future prospective studies or in the medical arm of randomized controlled studies in the presence of optimal medical therapy.

NHÂN CA GIANT CELL ARTERITIS of the BREAST TẠI MEDIC

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Giant cell arteritis (GCA) from the above article

Although giant cell arteritis is a systemic disease, on rare occasions the breast may be the primary organ of manifestation. In a review of the English medical literature up to 2008, Kadotani et al identified 20 reported cases, all of which were postmenopausal elderly women. Single or multiple lumps due to arteritis were present in 80% (16 of 20 patients), and redness and tenderness in the absence of lumps were present in 10%. Breast involvement was bilateral in 50% of the patients. Spontaneous breast pain and tenderness were presenting features in 85% of the patients. Systemic symptoms such as low-grade fever, arthralgia, myalgia, and those suggestive of polymyalgia rheumatica were present in 65% of the patients.

There have been no reports of mass lesions or other distinctive findings by mammography or ultrasonography. In a recent case report of a patient presenting with a lump in her breast and a negative mammogram, ultrasound of a stringlike thickening in the right axillary tail of the breast revealed a “halo sign” (hypoechoic circumferential wall thickening indicating edema), which, compared with biopsy, has been reported to have a sensitivity of 69% and a specificity of 82% for diagnosis of arteritis. In most cases reported in the medical literature, the diagnosis was made after excisional biopsy (a considerable amount of tissue is required to make the diagnosis of giant cell arteritis). In rare cases, the diagnosis was established before biopsy on the basis of systemic symptoms and ultrasound findings. Pathology shows fragmentation of the elastica in association with giant cell infiltration, intimal proliferation, and narrowing of the vascular lumina. Inflammatory cancer was suspected in four of seven cases reported by Kadotani et al.

Prednisone is the treatment of choice. It has been shown to improve both general symptoms and breast-specific manifestations of giant cell arteritis.

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STAGING BREAST CANCER by US-GUIDED AXILLARY NODE CORE BIOPSY

Abstract

The aim of this study was to see how effective ultrasound-guided needle biopsy was at detecting lymph node involvement in patients with early breast cancer. Patients with newly diagnosed invasive breast cancer underwent axillary ultrasound (US) where lymph node size and morphology were noted. A core biopsy (CB) was undertaken of any node greater than 5 mm in longitudinal section. Patients with benign CBs proceeded to sentinel lymph node (SLN) biopsy, whereas those with malignancy underwent axillary lymph node dissection (ALND). US and CB findings were correlated with final surgical histology in all cases.

One hundred and thirty-nine patients were examined, of whom 52.5% had lymph node metastases on final histology. One hundred and twenty-one patients (87%) underwent axillary node CB. The overall sensitivity of CB for detecting lymph node metastases was 53.4% (60.3% for macrometastases; 26.7% for micrometastases). The US morphological characteristics most

strongly associated with malignancy were absence of a hilum and a cortical thickness greater than 4 mm. However, one third of patients with normal lymph node morphology had nodal metastases, and only 12% of these were diagnosed on CB. CB of axillary lymph nodes can diagnose a substantial number of patients with lymph node metastases, allowing these patients to proceed directly to ALND, avoiding unnecessary SLN biopsy.

Keywords

Breast cancer . Axillary staging . Percutaneous biopsy . Histology . Ultrasound

TB Abscess of the Thyroid

Tuberculosis of the thyroid gland may present in two forms. The more common presentation is miliary spread to the thyroid gland as part of generalized dissemination. The less common form is focal caseous tuberculosis of the gland, which may present with localized swelling mimicking carcinoma, a cold abscess formation or as euthyroid nodular goiter. It may also manifest as subacute thyroiditis, or very rarely, as an acute abscess.

The signs and symptoms of thyroid TB are variable, and are most commonly associated with enlargement of the gland. Thyroid dysfunction is rare, but both hyperthyroidism and hypothyroidism have been reported.

Seed described 3 prerequisite conditions to be present for the diagnosis of thyroid tuberculosis:  the demonstration of acid fast bacilli within the thyroid, a necrotic or abscessed gland, and a definiite tuberculous focus outside the thyroid.

Histologic and bacteriologic confirmation are adequate to make the diagnosis, so that fulfillment of the third criterion is not essential. Characteristic histologic findings include epithelioid cell granulomas with, peripheral lymphocytic infiltration, and Langerhans giant cells. The demonstration of central caseation necrosis is a cytologic finding that is specific to tuberculosis. Other diagnostic tests include chest X-ray, sputum analysis, mycobacterial cultures and MTB-PCR.  However in some literature, AFB and culture analysis may not show tuberculosis and PCR can confirm TB in only 55% of the cases.  

In this case, there were no signs and symptoms suggestive of other foci of  TB in the body. The demonstration of epithelial cell granulomas with Langerhans giant cells and central caseation necrosis on histopathologic examination made the diagnosis of thyroid tuberculosis.

Antituberculous drugs remain the mainstay of treatment. Surgery may be indicated in the cases of acute abscess formation to avoid total destruction of the thyroid gland. Surgery may also be indicated to establish definite diagnosis when pre-operative workups are ambiguous.

Conclusion

Although seldom observed, tuberculosis should also be considered in the differential diagnosis of nodular lesions of the thyroid, particularly in communities with high TB prevalence. Ultrasound-guided FNAB is a useful diagnostic tool in the work-up of neck masses. In our case, confirmation of the diagnosis of TB of the thyroid was made by histopathologic examination. Treatment was mainly based on ATT. Surgical drainage and eventual thyroidectomy was deemed necessary due to the size of the abscess and establishment of the definitive diagnosis.

Primary and Secondary Breast Lymphoma

Primary and secondary breast lymphoma: prevalence, clinical signs and radiological features

Objectives: The purpose of this study was to determine the prevalence, clinical signs and radiological features of breast lymphoma.

Methods: This is a retrospective review of 36 patients with breast lymphoma (22 primary and 14 secondary). 35 patients were female and 1 was male; their median age was 65 years (range 24–88 years). In all patients, the diagnosis was confirmed histopathologically.

Results: The prevalence of breast lymphoma was 1.6% of all identified cases with non-Hodgkin lymphoma and 0.5% of cases with breast cancer. B-cell lymphoma was found in 94% and T-cell lymphoma in 6%. 96 lesions were identified (2.7 per patient). The mean size was 15.8±8.3 mm. The number of intramammary lesions was higher in secondary than in primary lymphoma. The size of the identified intramammary lesions was larger in primary than in secondary lymphoma. Clinically, 86% of the patients presented with solitary or multiple breast lumps. In 14%, breast involvement was diagnosed incidentally during staging examinations.

Conclusion: On mammography, intramammary masses were the most commonly seen (27 patients, 82%). Architectural distortion occurred in three patients (9%). In three patients (9%), no abnormalities were found on mammography. On ultrasound, the identified lesions were homogeneously hypoechoic or heterogeneously mixed hypo- to hyperechoic. On MRI, the morphology of the lesions was variable. After intravenous administration of contrast medium, a marked inhomogeneous contrast enhancement was seen in most cases. On CT, most lesions presented as circumscribed round or oval masses with moderate or high enhancement.



Echo Intensity of Median Nerve and Flexor Muscles of the Forearm

Quantitative evaluation of the echo intensity of the median nerve and flexor muscles of the forearm in the young and the elderly

Objectives: Musculoskeletal structures often appear brighter on imaging in the elderly, which makes it difficult to accurately delineate a peripheral nerve during ultrasound-guided regional anaesthetic procedures. The echo intensity of skeletal muscles is significantly increased in the elderly. However, there are no data comparing the echo intensity of peripheral nerves in the young and the elderly, which this study was designed to evaluate.

Methods: 13 healthy, young volunteers (aged <30 years) and 11 elderly patients (aged >60 years) who were scheduled to undergo orthopaedic lower limb surgery were recruited. The settings of the ultrasound system were standardised and a high-frequency linear array transducer was used for the scan. A transverse scan of the median nerve (MN) and the flexor muscles (FMs) at the left mid-forearm was performed and three video loops of the ultrasound scan were recorded for each subject. Still images were captured from the video loops and normalised. Computer-assisted greyscale analysis was then performed on these images to determine the echo intensity of the MN and the FMs of the forearm.

Results: The echo intensity of the MN and FMs of the mid-forearm was significantly increased in the elderly (p<0.005). There was also a reduction in contrast between the MN and the adjoining FM in the elderly (p=0.04).

Conclusion: Under the conditions of this study, the MN and the FMs in the forearm appeared significantly brighter than those in the young, and there was a loss of contrast between these structures in sonograms of the elderly.

3D Transrectal Ultrasound of Prostate Cancer

Detection of prostate cancer with three-dimensional transrectal ultrasound: correlation with biopsy results

Objectives: The aim of this study was to evaluate the role of three-dimensional transrectal ultrasound in the diagnosis of prostate cancer.
Methods: A total of 112 patients with elevated serum prostate-specific antigen (PSA) or a positive digital rectal examination were evaluated using three-dimensional greyscale transrectal ultrasound (3D-GS TRUS) and three-dimensional power Doppler sonography (3D-PDS). Target biopsies were obtained together with 12 core systematic biopsies. Pathological results were correlated with the imaging data.
Results: Cancers were detected in 269 biopsy sites from 41 patients. 229 sites of cancer were depicted by 3D-GS TRUS and 213 sites were depicted by 3D-PDS. 30 sites were missed by both 3D-GS TRUS and 3D-PDS. Abnormal prostate images depicted by 3D-GS TRUS and 3D-PDS were associated with lesions with a Gleason score of 6.9 or higher.

Conclusion: The detection rates of prostate cancer were significantly improved with 3D-GS TRUS and 3D-PDS on serum PSA levels >10 ng ml^–1 or 20 ng ml^–1.   3D-GS TRUS and 3D-PDS may improve the biopsy yield by determining appropriate sites for target and systematic biopsies. The abnormalities detected by 3D ultrasound were associated with moderate- and high-grade prostate cancers. However, based on the number of false-negative TRUS results, the use of systematic prostate biopsies should not be eliminated.

What Needs to Know about Urolithiasis

FURTHER READING: KIDNEY STONE MANAGING, from MAYO CLINIC

Kidney Stones Managing

Treatment alternatives for kidney stones can be as simple as waiting for the stone to pass or can involve medical or surgical treatment. Most often, kidney stone removal is scheduled ahead of time; it isn't usually an emergency. In rare instances, an emergency procedure may be needed to surgically drain any urine that has accumulated behind a kidney stone to help relieve pain and to minimize the risk of infection.

The size and location of the stone and the patient's preference and pain tolerance are key factors for selecting a treatment alternative. Most small kidney stones will pass through the urinary tract unaided. However, it's difficult to predict how painful passing a kidney stone will be. Some people prefer waiting for the stone to pass rather than undergoing a medical or surgical procedure for removal; others find this approach too unpredictable and anxiety-provoking. Urologists can facilitate stone passage using extracorporeal shock wave lithotripsy to break apart smaller kidney stones that are not located in the lower regions of the ureter (the tube from the kidney to the bladder). Small stones located in the lower third of the ureter require the use of a ureteroscope. Larger stones are removed using a surgical procedure called percutaneous nephrolithotomy.

This section includes information on:

·         Watchful Waiting

·         Extracorporeal Shock Wave Lithotripsy (ESWL)

·         Percutaneous Nephrolithotomy (PNL)

·         Ureteroscopic Stone Removal

Watchful Waiting

Even though 85 percent of kidney stones are small enough to pass during urination, fewer than 50 percent of patients chose this option. A person with a normal-size ureter can usually pass a kidney stone with a diameter less than 5 mm (about 3/16 of an inch) without significant pain or risk of kidney damage. Infection and blockage of the urinary tract are the primary complications associated with waiting for a kidney stone to pass. Long-term blockage of the urinary tract can lead to kidney damage. If the warning signs of a urinary tract infection or blockage develop—fever or chills and intense pain—it's time to seek medical attention.

Most stones pass within 72 hours after the symptoms first appear. However, for some people, it can take weeks to pass a kidney stone, with an unpredictable pattern and degree of pain. Shape and location of the stone may give clues to how easily the stone will pass. Some people experience only momentary and tolerable pain; for others, passing the stone can trigger intense and persistent pain. Because of this unpredictability, most patients prefer to have their kidney stone removed by a urologist rather than wait for passage.For other people, waiting for a kidney stone to pass may not be practical. For example, airline pilots or heavy-quipment operators may want to avoid a sudden attack of incapacitating abdominal pain at work.

The guidelines for waiting for a kidney stone to pass include:

·         Drink at least 3 quarts of water per day.

·         Stay physically active.

·         Use pain medication as recommended or prescribed by your doctor.

·         Urinate through a strainer to recover the stone for analysis.

·         If fever or chills develop or symptoms (pain) worsen, seek out immediate medical attention.

Extracorporeal Shock Wave Lithotripsy (ESWL)

Extracorporeal shock wave lithotripsy is used to treat 80 to 90 percent of kidney stones. Kidney stones smaller than 1.5 cubic centimeters (roughly the size of a marble) that are not located in the lower third of the ureter are usually treated with ESWL. ESWL is a noninvasive procedure that uses shock waves to break up the kidney stone in situ (in place).

Shock waves are zones of high pressure that travel through fluid, retaining their energy until a solid object is encountered. Shock waves are used to treat kidney stones because they can pass through the bones and tissues of the body without dissipating any energy, yet pulverize a kidney stone on impact. Once the stone has been crumbled, the fragments pass through the urinary tract and out of the body. For kidney stones located in the lower third of the ureter, the pelvis bone interferes with the imaging of the stone required for this procedure, so these stones are removed using a ureteroscope.

Preparing for the procedure may require limiting food and water, depending on the type of sedation to be used. The shock waves can be painful, so the procedure is usually performed using full sedation or general anesthesia, but on an outpatient basis. The procedure begins by either partially submerging the patient in a tub of water while he or she sits in a chair or having the patient recline on a water-filled cushion. Shock waves are then directed at the kidney stone while X-rays or ultrasound are used to monitor the location and status of the stone. The shock waves pound the stone until it crumbles and is passed in the urine. This usually requires 1,000 to 2,000 shock waves and takes approximately 30 minutes. Shock waves are loud, so patients wear earphones to protect their hearing during the procedure.

Recovery is quick; usually patients are able to leave the treatment center within a few hours. Normal activity can be resumed in two to three days. Fluid intake is encouraged to help pass the stone fragments. Some stone fragments may be too large to pass, and additional treatment with ESWL may be necessary. The likelihood of needing additional treatment depends largely on the experience of the urologist and the capability of the equipment to emit high-energy shock waves. Approximately 2 to 25 percent of people undergoing ESWL will need additional treatment to remove the kidney stone.

Approximately 1 million people have had this treatment since it was approved by the Federal Drug Administration in 1985. Documented side effects from this procedure include blood in the urine for a short time, minor bruising on the back or abdomen, and some discomfort as the stone fragments pass through the urinary tract. Recent data suggest a potentially increased incidence of diabetes or hypertension in patients who have undergone ESWL. Further research is underway to assess this potential link between ESWL and diabetes or hypertension.

Percutaneous Nephrolithotomy (PNL)

Percutaneous nephrolithotomy is used to remove kidney stones 2 cubic centimeters or larger (2 cubic centimeters is a little larger than a marble). In PNL, the urologist breaks up and removes the kidney stone through a small incision in the side using a nephroscope. A nephroscope is a telescope about the diameter of a person's pinkie finger used to examine and perform procedures on the kidneys. This procedure is approximately 95 percent effective at removing kidney stones when performed at hospitals experienced with it.

The procedure begins with a radiologist inserting a narrow guide wire, also known as a catheter, through a small incision (2 to 3 mm long, less than 1/8 of an inch) in the skin. The catheter is inserted using fluoroscopy, a specialized X-ray technique, to help guide the catheter through the kidney into the ureter while the patient is sedated. Once the guide wire is in place, the patient is moved into the operating room where the PNL procedure is completed under general anesthesia. Dilators are inserted along the guide wire to gradually enlarge the opening so it can accommodate the nephroscope. The urologist inserts the nephroscope, which is equipped with a fiber-optic light, to visualize the stone. All stones and fragments are removed through the nephroscope during the procedure, which usually takes about 15 to 45 minutes; none are left to pass through the urinary tract. If necessary, an ultrasonic probe or laser can be inserted through the nephroscope to break up the stone. A catheter is left in place for several days following the procedure to drain the kidney.

This procedure usually involves one to two days of hospitalization. During this time, additional imaging may be performed to confirm that the stones have been removed. If any stones remain, a nephroscope will be used to remove them; the procedure requires sedation only at this time. Once the stones have been removed, the catheter will be removed and the patient will be discharged from the hospital. Full recovery usually requires one to two weeks.

Ureteroscopic Stone Removal

If the kidney stone has moved from the kidneys down into the ureter, the tube that carries urine from the kidney to the bladder, ureteroscopy can be used to remove it. A urologist can use either extracorporeal shock wave lithotripsy or ureteroscopy to remove stones from the ureter. The technique chosen depends on the type of ESWL machine available and the preference and skills of the urologist.

A ureteroscope is a small, flexible telescope that is used to examine and perform procedures on the ureter. A ureteroscope enters the body through the urethra, following it into and then through the bladder to reach the ureter. A ureteroscope is equipped with fiber-optic lights and small working channels through which devices can be passed to break up the kidney stone, snare it, and remove it. If the stone is large, the urologist may use ultrasound, laser, or a technique called electrohydraulic lithotripsy to shatter the stone prior to removal. After the procedure, a small stent (tube) may be inserted in the ureter for a few days to minimize swelling and promote healing.

Typically the procedure is performed on an outpatient basis with most people returning to work within a few days. Although an incision is not needed, most patients undergoing this procedure receive local or general anesthesia. Preparing for anesthesia may involve abstaining from food and beverages prior to the exam; check with your healthcare provider for exact restrictions.

Ureteroscopy is not without risk; potential complications are perforating the ureter or causing scar tissue to develop. The risk of complication increases if the stone has been embedded in the wall of the ureter for more than two months.

Last reviewed on 10/13/09

 

EMERGENT PEDIATRIC ULTRASOUND

Appendicitis, intussusception, and hypertrophic pyloric stenosis (HPS) are three of the most common reasons for emergent abdominal imaging in pediatric patients. Although the use of computed tomography has risen dramatically over the past 2 decades, children are particularly at risk for the adverse effects of ionizing radiation, and even low-dose radiation is associated with a small but significant increase in lifetime risk of fatal cancer. In most emergency departments, the use of magnetic resonance (MR) imaging as a primary modality for the evaluation of a child with abdominal pain remains impractical due to its high cost, its limited availability, and the frequent need for sedation. Ultrasonography (US) does not involve ionizing radiation and, unlike MR imaging, is relatively inexpensive, is widely available, and does not require sedation. Another major advantage of US in abdominal imaging is that it allows dynamic assessment of bowel peristalsis and compressibility. Delayed diagnosis of any of the aforementioned disease processes can lead to serious morbidity and, in some cases, death. The ability to diagnose or exclude disease with US should be part of a core radiology skill set for any practice that includes a pediatric population.

© RSNA, 2012

Liver and Spleen Stiffness in Patients with Extrahepatic Portal Vein Obstruction

Liver and Spleen Stiffness in Patients with Extrahepatic Portal Vein Obstruction

Purpose: To evaluate liver stiffness (LS) and spleen stiffness (SS) in patients with extrahepatic portal vein obstruction (EHPVO).

Materials and Methods: Institutional research board approval and informed consent were obtained. LS and SS were measured in 65 consecutive patients with EHPVO. Patients underwent endoscopy, liver biopsy, liver function tests, abdominal ultrasonography, a detailed history, and examination. LS and SS measurements were also obtained in 50 age-matched healthy control subjects. Comparisons were made by using the Student t test, Mann-Whitney test for quantitative data, and χ² or Fisher exact test for qualitative data.

Results: Sixty-five patients with EHPVO (with a bleed, n = 45; without a bleed, n = 20; mean age, 25.4 years ± 10.7 [standard deviation]; 29 men, 36 women) were enrolled. Twenty-two (34%) had hypersplenism. LS (P = .001) and SS (P = .01) were higher in patients with EHPVO (6.7 kPa ± 2.3 and 51.7 kPa ± 21.5, respectively) than in control subjects (4.6 kPa ± 0.7 and 16.0 kPa ± 3.0, respectively). Patients who had a bleed had higher SS than did those without a bleed (60.4 kPa ± 5.4 vs 30.3 kPa ± 14.2, P = .01). There was no significant difference in age (26.7 years ± 10.4 vs 22.5 years ± 9.8, P = .8) and median duration of disease (4.5 years [range, 1–26 years] vs 6.0 years [range, 1–22 years], P = .23) in patients with a bleed versus those without. With a cutoff of 5.9 kPa for LS, sensitivity and specificity for detection of a variceal bleed were 67% and 75%, respectively. An SS cutoff of 42.8 kPa yielded sensitivity and specificity of 88% and 94%, respectively.

Conclusion: LS and SS were higher in patients with EHPVO than in control subjects, and patients with a history of a bleed had a higher SS than did those without a bleed.

© RSNA, 2012

Invasive Breast Cancer: SWE Findings and Histologic Factors

Invasive Breast Cancer: Relationship between Shear-wave Elastographic Findings and Histologic Prognostic Factors

Purpose: To compare the histologic prognostic feature of invasive breast cancer with mean stiffness as measured with shear-wave elastography.

Materials and Methods: This retrospective study was exempted from ethical committee review. Patient consent for use of images for research was obtained. The study group comprised 101 consecutive women (age range, 38–91 years) with solid lesions identified during routine breast ultrasonography (US) performed between April 2010 and March 2011 and subsequently confirmed at histologic examination to be invasive cancers. Four elastographic images in two orthogonal planes were obtained of each lesion, and mean stiffness values were obtained from each image. Histologic findings following surgery were used for comparison, namely histologic grade, tumor type, invasive size, vascular invasion status, and lymph node status. Relationship between mean stiffness and histologic parameters was investigated by using a general linear model and multiple regression analysis.

Results: High histologic grade (P < .0001), large invasive size (P < .0001), lymph node involvement (P < .0001), tumor type (P < .0001), and vascular invasion (P = .0077) all showed statistically significant positive association with high mean stiffness values. Multiple linear regression indicated that invasive size is the strongest pathologic determinant of mean stiffness (P < .0001), with histologic grade also having significant influence (P = .022).

Conclusion: In this study, breast cancers with higher mean stiffness values at shear-wave elastography had poorer prognostic features.

© RSNA, 2012