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K Shanmuganathan

Publications and source records attributed to K Shanmuganathan.

At least 19 recordsLinked to original sources
PubMed2006

Multidetector-row computed tomography imaging of splenic trauma.

The spleen is the intra-abdominal organ most often injured as a result of blunt trauma. Multidetector-row computed tomography (MDCT) plays an important role in the detection and characterization of splenic injury. It has been shown to be highly accurate and can detect splenic vascular lesions, the presence of which has been shown to be a predictor of failure of nonoperative management. The increased use of angiography and splenic artery embolization in the management of such injuries has led to improved success rates with nonoperative management. This article reviews the various appearances of the injured spleen and discusses the use of MDCT in the initial evaluation of injury. The indications for angiography and embolization are reviewed, with examples of appearances of the postembolization spleen.

Angiography↗
PubMed2006

Chance-type fractures of the thoracolumbar spine: imaging analysis in 53 patients.

OBJECTIVE: Chance-type fractures are subtle unstable injuries that are often associated with intraabdominal injuries. CT-based observations made during routine interpretations revealed involvement of a burst component to this fracture pattern and a clue on the transaxial images to its presence. The purpose of this review was to determine how often these features occurred in a retrospective study of a large sample because these findings influence diagnosis and management. MATERIALS AND METHODS: A retrospective review of all patients identified from the University of Maryland Shock Trauma Center trauma registry and IDXRad system diagnosed with flexion-distraction injuries of the thoracolumbar spine over an 8-year period was performed. Three trauma radiologists assessed the admission spinal radiographs, CT studies with multiplanar images, and available MRI examinations. Imaging findings were confirmed by consensus. Abdominopelvic CT studies and surgical reports were reviewed for evidence and type of intraabdominal injury. A literature review of previous similar series was performed. RESULTS: Fifty-three patients were identified for inclusion in the study. Associated intraabdominal injury occurred in 40% and most commonly involved the bowel and mesentery. A close examination of the fracture patterns on CT revealed that a burst-type fracture with posterior cortex buckling or retropulsion was a common finding (48%). Also, serial transaxial CT images often (76%) showed a gradual loss of definition of the pedicles that we refer to as the "dissolving pedicle" sign. The study showed that the horizontally oriented fracture planes through the posterior elements can often be recognized radiographically, but these fractures can be very subtle. CONCLUSION: Intraabdominal injuries occurred in 40% of flexion-distraction thoracolumbar fractures in our study cohort, which is slightly lower than previously reported. About half of the patients with this injury displayed a burst-type component that could have a significant influence on surgical management. The dissolving pedicle sign can assist in recognition of this often subtle injury on transaxial CT.

Abdominal Injuries↗
PubMed2005

Multidetector-row CT of right hemidiaphragmatic rupture caused by blunt trauma: a review of 12 cases.

AIM: To determine the usefulness of multidetector-row CT (MDCT) with multiplanar reformatted (MPR) images in the sagittal and coronal plane in diagnosing acute right hemidiaphragmatic rupture. MATERIALS AND METHODS: Twelve patients were identified who received chest and abdominal MDCT after major blunt trauma diagnosed with right diaphragmatic injury. Sagittal and coronal reformations were performed in all cases. The images were retrospectively reviewed by two experienced radiologists for signs of right diaphragm injury, such as direct diaphragm discontinuity, the "collar sign", the "dependent viscera sign", and intra-thoracic location of herniated abdominal contents. RESULTS: Of the 12 cases of right hemidiaphragm rupture, diaphragm discontinuity was seen in seven (58%) cases, the collar sign in five (42%), the dependent viscera sign in four (33%), and transdiaphragmatic herniation of the right colon and fat in another. Two variants of the collar sign were apparent on high-quality sagittal and coronal reformations. The first, termed the "hump sign", describes a rounded portion of liver herniating through the diaphragm forming a hump-shaped mass, and the second, termed the "band sign," is a linear lucency across the liver along the torn edges of the hemidiaphragm. The hump sign occurred in 10 (83%) patients and the band sign in four (33%). CONCLUSION: MDCT is very useful in the diagnosis of right hemidiaphragm injury caused by blunt trauma when sagittal and coronal reformatted images are obtained, and should allow more frequent preoperative diagnosis.

Accidents, Traffic↗
PubMed2005

Multidetector CT evaluation of abdominal trauma.

CT is the imaging modality of choice to evaluate blunt abdominal trauma. With the advent of multidetector CT (MDCT), scanning times have progressively decreased while image resolution has increased owing to thinner collimation and reduced partial volume and motion artifacts. MDCT also allows high quality two-dimensional and three-dimensional multiplanar reformatted images to be obtained, which aid in the diagnosis of the complex multisystem injuries seen in the trauma patient. This article describes the authors' current imaging protocol with 16-detector MDCT, the spectrum of CT findings seen in patients with blunt abdominal injuries, and the role MDCT has in guiding injury management.

Abdominal Injuries↗
PubMed2005

Ultrasonography for interval assessment in the nonoperative management of hepatic trauma.

Abdominal ultrasonography (US) is gaining widespread acceptance as a valuable diagnostic tool in the initial evaluation of trauma victims. We investigated the utility of US as a follow-up radiologic study in nonoperative hepatic trauma. Patients with liver injury designated for nonoperative management were prospectively studied over a 2-year period at our primary adult resource center for trauma. Computed tomography (CT) and radiologist-performed US were obtained at admission and at 1 week. The ability of US to detect lesions, fluid, and complications was evaluated by comparing with the corresponding CT. Twenty-five hepatic trauma patients in the study were successfully managed nonoperatively and had both initial and follow-up US and CT scans: 1 (4%) grade I, 5 (20%) grade II, 7 (28%) grade III, 7 (28%) grade IV, and 5 (20%) grade V. Four complications developed [biloma (3) and biliary fistula (1)] in 3 patients with grade IV injury and 1 with a grade II injury. Interval US appropriately detected a complication or confirmed the absence of complication in all (13/13, 100%) patients with low-grade (I-III) injury and only missed a small biloma in one patient with a grade IV injury. Interval US and CT agreement was 92 per cent for change in hemoperitoneum or parenchymal lesion. Ultrasonography is a convenient imaging modality in the evaluation of hepatic trauma. US is sufficient to detect or exclude complications in low-grade injuries. In high-grade injuries, US may be an adjunct to CT for definitive interval assessment.

Abdominal Injuries↗
PubMed2004

Penetrating torso trauma: triple-contrast helical CT in peritoneal violation and organ injury--a prospective study in 200 patients.

PURPOSE: To assess the accuracy of computed tomography (CT) in demonstrating the presence or absence of peritoneal violation and type of intraperitoneal organ injury, if any, in hemodynamically stable patients with penetrating torso trauma but without definite peritoneal signs or radiographic evidence of free intraperitoneal air. MATERIALS AND METHODS: During a 29-month period, helical CT with oral, rectal, and intravenous contrast material (triple-contrast) was performed in 200 hemodynamically stable patients, including 169 men (age range, 15-85 years; mean age, 31 years) and 31 women (age range, 17-45 years; mean age, 28 years) with penetrating torso trauma. The study group included 86 patients with gunshot wounds, 111 with stab wounds, and three impaled by sharp objects. CT scans were evaluated prospectively by three trauma radiologists for evidence of peritoneal violation to determine injury to intra- or retroperitoneal solid organs, bowel, mesentery, vascular structures, diaphragm, and urinary tract. Sensitivity, specificity, and accuracy of CT in the diagnosis of peritoneal violation were determined. RESULTS: CT findings aided diagnosis of peritoneal violation in 34% of patients (68 of 200) and were negative for peritoneal violation in 66% of patients (132 of 200). Two patients with negative CT findings failed to improve with observation and underwent therapeutic laparotomy. CT had 97% sensitivity (66 of 68 findings), 98% specificity (130 of 132 findings), and 98% accuracy (196 of 200 findings) for peritoneal violation. CT aided diagnosis of 28 hepatic, 34 bowel or mesenteric, seven splenic, and six renal injuries. Laparotomy based on CT findings in 38 patients was considered therapeutic in 87% (33 of 38) and nontherapeutic in 8% (three of 38) and had negative results in 5% (two of 38). CONCLUSION: Triple-contrast helical CT accurately demonstrates peritoneal violation and visceral injury in patients with penetrating torso wounds.

Abdominal Injuries↗
PubMed2004

CT diagnosis of splenic infarction in blunt trauma: imaging features, clinical significance and complications.

AIM: The object of this study is to describe the appearance, complications, and outcome of segmental splenic infarctions occurring after blunt trauma using computed tomography (CT). MATERIALS AND METHODS: Thirteen blunt trauma patients were identified with splenic infarction on contrast-enhanced CT. CT images were retrospectively reviewed and the percentage of infarcted splenic tissue and presence of splenic injury separate from the site of infarction were identified. Splenic angiograms were reviewed and follow-up CT images were assessed for interval change in the appearance of the infarcts. RESULTS: The mean age of patients was 32 years and the most common mechanism of injury was road traffic accident. The majority (54%) had 25-50% infarction of the spleen. Splenic angiograms were performed in nine patients and seven demonstrated wedge-shaped regions of decreased perfusion corresponding to the infarction seen on CT with no need for intervention. Eleven patients underwent a follow-up CT that demonstrated the following: no significant change in six, near-complete resolution in two, delayed appearance of infarction in one, abscess formation in one, and delayed splenic rupture in one. CONCLUSION: Segmental splenic infarction is a rare manifestation of blunt splenic trauma. The diagnosis is readily made using contrast-enhanced CT. The majority will decrease in size on follow-up CT and resolve without clinical sequelae. Resolution of infarction is also seen and these cases are best described as temporary perfusion defects. Splenic abscess or delayed rupture are uncommon complications that may necessitate angiographic or surgical intervention.

Accidental Falls↗
PubMed2004

Blunt abdominal trauma patients: can organ injury be excluded without performing computed tomography?

PURPOSE: The purpose of this study was to determine whether admission non-computed tomography (CT) criteria can exclude intra-abdominal injury in stable patients sustaining blunt abdominal trauma. METHODS: Seven hundred fourteen hemodynamically stable patients with suspicion of blunt abdominal trauma were included in the study. Admission data for clinical examination, sonography, routine laboratory studies, chest/pelvic radiographic findings, and Glasgow Coma Scale (GCS) score were recorded. Each patient underwent helical abdominal CT. Injuries were considered major if they required surgery or angiographic intervention. At the authors' institution, angiography is routinely performed if there is a splenic injury of American Association for the Surgery of Trauma grade II or higher or a liver injury of American Association for the Surgery of Trauma grade III or higher. Statistical analysis was performed to determine the value of isolated and combined clinical, radiologic, and laboratory parameters in depicting an intra-abdominal injury with regard to CT results and clinical follow-up. RESULTS: The best combination of criteria to identify a major abdominal injury was obtained when sonography, chest radiography, and three laboratory parameters (serum glutamic oxaloacetic transaminase, white blood cell count, and hematocrit) were normal: 22% (129 of 589) of patients without major injuries fulfilled these criteria. The only combination of criteria that completely excluded intra-abdominal injury was obtained when clinical criteria combined with a Glasgow Coma Scale score > 13, bedside radiologic studies, and laboratory data were all normal, but only 12% (68 of 578) of patients without abdominal injury fulfilled these criteria. CONCLUSION: After blunt abdominal trauma, admission non-CT criteria can at best identify 12% of patients without intra-abdominal injuries and 22% of patients without major injuries.

Abdominal Injuries↗
PubMed2002

Imaging of traumatic diaphragmatic injuries.

Traumatic diaphragmatic injury (TDI) occurs in approximately 6% of patients after major blunt trauma to the abdomen. Detection of such injuries is often problematic because of nonspecific clinical signs and the presence of additional intra-abdominal injuries. As the use of nonsurgical management to treat solid organ injuries increases, helical computed tomography (CT) must play a much greater role in the detection of intra-abdominal injuries. Therefore, it is crucial that diaphragmatic injuries are not overlooked, as fewer will be diagnosed at exploratory laparotomy. This article reviews the recent advances in helical CT that are helpful in diagnosing TDI and addresses the selected application of magnetic resonance imaging.

Hernia, Diaphragmatic, Traumatic↗
PubMed2001

CT findings after embolization for blunt splenic trauma.

PURPOSE: To determine complications after transcatheter embolization for blunt splenic injury as recognized with computed tomography (CT). MATERIALS AND METHODS: From March 1997 to January 2000, 80 patients underwent transcatheter embolization after blunt splenic injury, of whom 53 underwent abdominal CT examination before and after embolization. Preembolization CT scans were reviewed to determine grade of injury, and postembolization CT scans were reviewed to identify complications secondary to embolization. Arteriography results were reviewed to determine findings and method and location of embolization. RESULTS: Splenic infarcts occurred in 63% of patients after proximal embolization and in 100% of patients after distal embolization. Infarcts after distal embolization tend to be larger and occur just distal to the embolization material, whereas infarcts after proximal embolization tend to be smaller, multiple, and located in the periphery. Most infarcts resolved without sequelae. Seven patients developed gas within an infarct or subcapsular fluid collection. Two collections were drained and found to be sterile and one patient had a splenic abscess at laparotomy. CONCLUSIONS: Infarcts are common after splenic embolization. Gas may be present within an infarct after embolization with Gelfoam; however, the presence of air/fluid level is a better predictor of abscess.

Adult↗
PubMed2001

Helical computed tomography of bowel and mesenteric injuries.

BACKGROUND: The role of computed tomography in diagnosing hollow viscus injury after blunt abdominal trauma remains controversial, with previous studies reporting both high accuracy and poor results. This study was performed to determine the diagnostic accuracy of helical computed tomography in detecting bowel and mesenteric injuries after blunt abdominal trauma in a large cohort of patients. METHODS: One hundred fifty patients were admitted to our Level I trauma center over a 4-year period with computed tomographic (CT) scan or surgical diagnosis of bowel or mesenteric injury. CT scan findings were retrospectively graded as negative, nonsurgical, or surgical bowel or mesenteric injury. The CT scan diagnosis was then compared with surgical findings, which were also graded as negative, nonsurgical, or surgical. RESULTS: Computed tomography had an overall sensitivity of 94% in detecting bowel injury and 96% in detecting mesenteric injury. Surgical bowel cases were correctly differentiated in 64 of 74 cases (86%), and surgical mesenteric cases were correctly differentiated from nonsurgical in 57 of 76 cases (75%). CONCLUSION: Helical CT scanning is very accurate in detecting bowel and mesenteric injuries, as well as in determining the need for surgical exploration in bowel injuries. However, it is less accurate in predicting the need for surgical exploration in mesenteric injuries alone.

Abdominal Injuries↗
PubMed2001

Determining the need for laparotomy in penetrating torso trauma: a prospective study using triple-contrast enhanced abdominopelvic computed tomography.

BACKGROUND: The nontherapeutic laparotomy rate in penetrating abdominal trauma remains high and the morbidity rate in these cases is approximately 40%. Selective management, rather than mandatory laparotomy, has become a popular approach in both stab wounds and gunshot wounds. The advent of spiral technology has stimulated a reassessment of the role of computed tomography (CT) in many aspects of trauma care. We prospectively investigated the current utility of triple-contrast CT as a diagnostic tool to facilitate initial therapeutic management decisions in penetrating torso trauma. METHODS: We studied hemodynamically stable patients with penetrating injury to the torso (abdomen, pelvis, flank, back, or lower chest) without definite indication for laparotomy, admitted to our trauma center during the 1-year period from 7/99 through 6/00. Patients underwent triple-contrast enhanced spiral CT as the initial study. A positive CT scan was defined as any evidence of peritoneal violation (free air or fluid, contrast leak, or visceral injury). Patients with positive CT, except those with isolated solid viscus injury, underwent laparotomy. Patients with negative CT were observed. RESULTS: There were 75 consecutive patients studied: mean age 30 years (range 15-85 years); 67 (89%) male; 41 (55%) gunshot wound, 32 (43%) stab wound, 2 (3%) shotgun wound; mean admission systolic blood pressure 141 mm Hg (range 95-194 mm Hg); 26 (35%) had positive CT and 49 (65%) had negative CT. In patients with positive CT, 18 (69%) had laparotomy: 15 therapeutic, 2 nontherapeutic, and 1 negative. Five patients had isolated hepatic injury and 2 had hepatic and diaphragm injury on CT and all were successfully managed without laparotomy. Of these seven patients, three had angioembolization and two had thoracoscopic diaphragm repair. In patients with negative CT, 47/49 (96%) had successful nonoperative management and 1 had negative laparotomy. The single CT-missed peritoneal violation had a left diaphragm injury at laparotomy. CT accurately predicted whether laparotomy was needed in 71/75 (95%) patients. CONCLUSION: In penetrating torso trauma, triple-contrast abdominopelvic CT can accurately predict need for laparotomy, exclude peritoneal violation, and facilitate nonoperative management of hepatic injury. Adjunctive angiography and investigation for diaphragm injury may be prudent.

Abdominal Injuries↗
PubMed2001

Using CT to diagnose tracheal rupture.

OBJECTIVE: A retrospective study was performed to assess CT sensitivity for diagnosing tracheal rupture. Intubated cadaver tracheas were examined to assess endotracheal tube balloon overdistention and deformity and to evaluate the relationship of balloon pressures to tracheal injury. MATERIALS AND METHODS: Neck or chest CT scans of 14 patients with tracheal rupture and 41 control trauma patients with pneumomediastinum but without tracheal injury were reviewed and compared to assess the presence and location of extrapulmonary air, whether direct visualization of tracheal wall disruption was possible, the size and shape of endotracheal tube balloon, signs of transtracheal balloon herniation in intubated patients, and the location of the extratracheal endotracheal tube. Intact and experimentally injured cadaver tracheas were used to evaluate tube balloon pressure and configuration. RESULTS: All 14 patients with tracheal rupture had deep cervical air and pneumomediastinum. Overdistention of the tube balloon occurred in 71% (5/7) of the intubated patients, and balloon herniation occurred in 29% (2/7). Direct tracheal injury was seen in 71% (10/14) of the patients as a wall defect (n = 8) or deformity (n = 2). Overall, CT was 85% sensitive for detecting tracheal injury. Patients with tracheal injury had a significantly lower incidence of pneumothorax (p = 0.01) than did the control group. The CT appearance of balloon herniation through defects in the cadaver tracheas closely mimicked those of patients with tracheal injury. The amount of balloon pressure required to rupture the intubated trachea was extremely high and rupture was difficult to obtain. CONCLUSION: CT can reveal tracheal injury and can be used to select trauma patients with pneumomediastinum for bronchoscopy, leading to early confirmation and treatment.

Adolescent↗
PubMed2001

Triple-contrast helical CT in penetrating torso trauma: a prospective study to determine peritoneal violation and the need for laparotomy.

OBJECTIVE: A prospective study was performed to determine the usefulness of triple-contrast helical CT in predicting peritoneal violation and the need for laparotomy in the treatment of penetrating torso trauma. SUBJECTS AND METHODS: Triple-contrast helical CT scans were obtained in 104 hemodynamically stable patients with penetrating injuries to the torso (thoracoabdominal region including tangential wounds to the anterior abdomen, flank, back, and pelvis) over a 17-month period. The study group included 54 patients with gunshot wounds and 50 with stab wounds. No patient had a radiographic or clinical indication for immediate laparotomy. A positive finding on CT was defined as evidence of peritoneal violation or injury to the retroperitoneal colon, major vessel, or urinary tract. Patients with a positive CT, except patients with isolated liver injury or free fluid, underwent laparotomy. Patients with a negative finding on CT were initially observed. RESULTS: CT studies were positive in 35 (34%) of 104 patients and negative in 69 (66%) of 104 of patients. Laparotomy was performed in 21 (60%) of 35 patients with positive CT; 19 (86%) of 22 were therapeutic, two (9%) were nontherapeutic, and one (5%) was negative (no injury was found). Nine patients with isolated hepatic injuries were successfully treated without laparotomy. Among patients with a negative CT, 67 (97%) of 69 were treated nonoperatively with success. CT had 100% (19/19) sensitivity, 96% (69/72) specificity, 100% (69/69) negative predictive value, and 97% (101/104) accuracy in predicting the need for laparotomy. CONCLUSION: Triple-contrast helical CT can accurately predict the need for laparotomy and exclude peritoneal violation in penetrating torso trauma including tangential abdominal wounds.

Abdominal Injuries↗
PubMed2000

Imaging of diaphragmatic injuries.

Multiple imaging modalities are available for the preoperative diagnosis of diaphragmatic injury. Chest radiographs are the initial and most commonly performed imaging study to evaluate the diaphragm after trauma. When chest radiography is indeterminate, spiral computed tomography (CT) with thin sections and reformatted images is the next study of choice, particularly because most hemodynamically stable patients with blunt diaphragm injury will require an admission CT examination to evaluate the extent and anatomical sites of coexisting thoracoabdominal injuries. Magnetic resonance imaging is used to evaluate the diaphragm for patients with clinical suspicion but an indeterminate diagnosis after chest radiography and spiral CT.

Diaphragm↗
PubMed2000

CT criteria for management of blunt liver trauma: correlation with angiographic and surgical findings.

PURPOSE: To determine the contrast material-enhanced computed tomographic (CT) criteria for selection of hemodynamically stable patients with blunt hepatic injury for angiographic evaluation. MATERIALS AND METHODS: Seventy-two patients with blunt liver injury underwent CT and hepatic angiography. Hepatic injuries were graded with CT-based classification. Scans were assessed for evidence of contrast extravasation and laceration or contusion extending into the hepatic vein(s), inferior vena cava, porta hepatis, or gallbladder fossa. Medical, angiographic, and surgical records were reviewed to determine angiographic findings, surgical indications and findings, and outcomes. RESULTS: Compared with hepatic angiography, CT was 65% (11 of 17 patients) sensitive and 85% (41 of 48 patients) specific for detection of arterial vascular injury. When CT severity grades 2 and 3 were analyzed, the sensitivity and specificity of CT were 100% (three of three patients) and 94% (34 of 36 patients), respectively (P <.001). Injury involving at least one major hepatic vein was found in 15 (88%) of 17 patients who required liver-related surgery and in 23 (42%) of 55 of the other patients (P <.01). CONCLUSION: CT-based criteria, including hepatic injury grade, signs of arterial vascular injury, and presence or absence of major hepatic venous involvement assists in selecting patients for hepatic angiography and those at increased risk of ongoing or delayed hepatic bleeding or other posttraumatic complications.

Adolescent↗
PubMed2000

Nonsurgical management of blunt splenic injury: use of CT criteria to select patients for splenic arteriography and potential endovascular therapy.

PURPOSE: To determine if contrast material-enhanced spiral computed tomography (CT) can be used to select patients with blunt splenic injuries to undergo arteriographic embolization. MATERIALS AND METHODS: During a 15-month period, 78 patients who were hemodynamically stable and required no immediate surgery underwent contrast-enhanced spiral CT followed by splenic arteriography. CT scans were assessed for splenic vascular contrast material extravasation or posttraumatic splenic vascular lesions. Medical records were reviewed for splenic arteriographic results and clinical outcome. RESULTS: There were 25 grade I, 12 grade II, 27 grade III, 12 grade IV, and two grade V splenic injuries. CT showed active contrast material extravasation in seven patients and splenic vascular lesions in 19 patients. At CT, splenic vascular contrast material extravasation was 100% (seven of seven patients) and a posttraumatic splenic vascular lesion was 83% (10 of 12 patients) sensitive on the basis of arteriographic or surgical outcome in predicting the need for transcatheter embolization or splenic surgery. Overall, CT had a sensitivity of 81% (17 of 21 patients), a specificity of 84% (48 of 57 patients), negative and positive predictive values of 92% (48 of 52 patients) and 65% (17 of 26 patients), respectively, and an accuracy of 83% (65 of 78 patients) in predicting the need for splenic injury treatment. CONCLUSION: Contrast-enhanced spiral CT plays a valuable role in selecting hemodynamically stable patients with splenic vascular injury who may be treated with transcatheter therapy and potentially improves the success rate of nonsurgical management.

Adolescent↗