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M Pozniak

Publications and source records attributed to M Pozniak.

5 recordsLinked to original sources
PubMed2000

Determination of stone composition by noncontrast spiral computed tomography in the clinical setting.

OBJECTIVES: Several investigators have evaluated noncontrast computed tomography (NCCT) in predicting stone composition in vitro. We assessed NCCT in predicting stone composition in patients presenting to our emergency room with flank pain and stone disease. METHODS: One hundred twenty-nine patients presenting to our university hospital with flank pain underwent renal colic protocol NCCT scans at the request of the emergency room physicians. A General Electric, high-speed advantage CT scanner was used at 120 kV, 200 mA, and 1.4:1 pitch, with collimation varying between 3 and 5 mm. Ninety-nine patients with predominantly (greater than 50%) calcium oxalate or uric acid composition after either stone passage or stone removal were identified. Each scan was analyzed by one of two radiologists, who determined the predominant attenuation for each stone. Stones once passed or retrieved were analyzed by Urocor Laboratories. The attenuation and attenuation/size ratio (peak attenuation/size in millimeters) were compared with the results of the stone analysis. RESULTS: Eighty-two calculi predominantly composed of calcium oxalate and 17 calculi predominantly composed of uric acid were identified in 99 patients. The calculi ranged in size from 1 to 28 mm. A significant difference (P = 0.017, unpaired t test) was found between the Hounsfield measurement of uric acid calculi (mean 344 +/- 152 HU) and the Hounsfield measurement of calcium oxalate calculi (mean 652 +/- 490 HU). If only the Hounsfield units from stones 4 mm or larger were compared, the data were even more compelling (P = 0.002). However, using an attenuation/size ratio cutoff of greater than 80, the negative predictive value was 99% that a stone would be predominantly calcium oxalate. CONCLUSIONS: Using peak attenuation measurements and the attenuation/size ratio of urinary calculi from NCCT, we were able to differentiate between uric acid and calcium oxalate stones.

Calcium Oxalate↗
PubMed1998

Computed tomographic angiography with three-dimensional reconstruction in patients with complex diverticular disease and portal hypertension: report of a case.

We report a case of a patient with portal hypertension secondary to alcoholic cirrhosis (Child's Class C) who initially presented with a colovaginal fistula secondary to acute sigmoid diverticulitis. The patient had a prior history of hepatic cirrhosis with ascites, coagulopathy, and portal hypertension. Computed tomography of the abdomen and pelvis demonstrated a large diverticular phlegmon and ascites. Computed tomographic angiography demonstrated a large left anterior abdominal wall varix in the region of the anticipated sigmoid resection. Three-dimensional reconstruction of the computed tomographic angiography further delineated the path of this large varix, confirming the increased risk from surgical intervention. Following initial conservative treatment with intravenous antibiotics, parenteral nutrition, and percutaneous abscess drainage, a transjugular intrahepatic portosystemic shunt procedure was performed to decompress the portal system varices. A repeat computed tomographic scan with three-dimensional reconstruction confirmed decompression of the varix. A successful sigmoid resection was subsequently performed. Preoperative computed tomographic angiography with three-dimensional reconstruction is a useful adjunct in planning the operative strategy in patients with complex intraabdominal pathology and collateral portovenous flow secondary to portal hypertension.

Abdomen↗
PubMed1992

Popliteal entrapment as a result of neurovascular compression by the soleus and plantaris muscles.

Intermittent claudication may occur in well-conditioned athletes because of an unusual form of popliteal artery entrapment that results from overtraining. These patients complain of calf muscle cramping, rapid limb fatigue, and occasional paresthesias on the plantar surface of the foot when running on inclines or when repetitive jumping is performed. Results of plethysmographic screening tests for popliteal entrapment are positive in these patients. Magnetic resonance angiography and intravenous digital subtraction angiography studies, however, do not demonstrate findings typical of anatomic popliteal entrapment. No evidence exists of aberrant positioning of the popliteal artery in foot neutral positioning, but with forced plantar flexion, the neurovascular bundle is deviated and compressed laterally. Surgical exploration of the popliteal fossa demonstrates no obvious musculotendinous abnormality. Symptoms of claudication and arterial compression are relieved by surgical release of the soleus muscle from its tibial attachments, resection of its fascial band, and resection of the plantaris muscle.

Adolescent↗
PubMedDate not supplied

Anti-low-density lipoprotein antibodies in alcoholics without and with liver disease and in social drinkers.

Antibodies directed to native and to in-vitro acetaldehyde-modified (ethylated) low-density lipoproteins (LDL) were determined in 28 alcoholic subjects divided into two groups: one with no clinical nor laboratory evidence of liver involvement and the second with histologically proven alcohol-related liver disease. The control group consisted of 18 individuals who drank alcohol socially. In the individuals with alcoholic liver disease IgG reactivity against both native and ethylated LDL was significantly higher than in alcoholic individuals without liver injury. High levels of IgG reactivity in individuals with alcoholic liver disease were also observed against malondialdehyde-modified, methylated, acetylated and carbamylated LDL. A selective high anti-ethylated LDL IgG reactivity was observed in 11% of control subjects.

Acetaldehyde↗