Acoustic neuromas: Gd-DTPA enhancement in MR imaging

Magnetic resonance (MR) imaging examinations were performed in ten patients with 12 acoustic neuromas before and after intravenous administration of 0.1 mmol/kg body weight gadolinium-diethylenetriamine pentaacetic acid (Gd-DTPA). The degree of enhancement was greatest with the inversion recovery sequence 1,500/500/44 (repetition time [TR]/inversion time/echo delay time [TE]), followed by spin-echo (SE) 544/44 (TR/TE) sequences, then by SE 1,500/44 and SE 1,500/80 sequences. After enhancement there was a 50% reduction for measured T1 values, 33% for T2, and no significant change for proton density. There were no toxic effects on patients. Enhanced CT scans failed to demonstrate lesions in six of 12 cases. Air-CT technique improved sensitivity in four of five cases. Enhanced MR imaging added significant clinical information in two small intracanalicular tumors and in one recurrent tumor.     

Immunoglobulin and T cell receptor gene configuration in acute lymphoblastic leukemia of infancy

We examined immunoglobulin (Ig) heavy chain, K light chain, and T cell receptor (TCR) gamma and beta gene configuration in the leukemic cells from a series of infants aged less than 1 year with acute lymphoblastic leukemia (ALL). Each of these 11 cases demonstrated leukemic cell surface antigens that have been correlated with a B cell precursor phenotype. Of the 11, lymphoblasts of 4 retained the germline configuration of both Ig and TCR loci, whereas 7 had rearranged the Ig heavy chain gene. Two of these seven showed light chain gene rearrangement. TCB beta chain rearrangement had occurred in only one of the 11 patients' tumors. No TCR gamma chain rearrangements were identified. These results are in contrast to earlier studies of B cell precursor ALL in children in which Ig heavy chain gene rearrangements were evident in every case and approximately 40% showed Ig light chain rearrangement as well. In addition, 45% of cases of B cell precursor ALL of children had rearranged their gamma TCR genes, and 20% had rearranged beta. These data suggest that ALL in infancy represents an earlier stage of B cell development than is found in B cell precursor ALL of children. ALL in the infant age group has been associated with the worst prognosis of all patients with ALL. This study suggests that the disease in infants differs not only clinically, but also at the molecular genetic level, from the disease in children.     

Ultrasonography guided rectus sheath catheters versus epidural analgesia for open colorectal cancer surgery in a single centre

Introduction

Epidural anaesthesia (EA) has been the accepted standard for postoperative analgesia in open abdominal surgery. However, it is not without significant risk. This study aimed to audit the effect of EA and ultrasonography placed rectus sheath catheters (RSCs) on analgesia as well as the incidence of postoperative complications following open colorectal cancer surgery.

Methods

A three-year retrospective case note review was undertaken of all patients undergoing open colorectal cancer surgery at the Royal Devon and Exeter Hospital NHS Foundation Trust who received either EA or RSC for postoperative analgesia under the care of the senior authors. A single surgeon and single anaesthetist were practitioners.

Results

The case notes of 120 patients were reviewed retrospectively: 85 patients had EA and 24 RSC while 11 patients were excluded from the study. The EA group experienced a significantly higher incidence of hypotension (systolic blood pressure <130mmHg) than the RSC group on the first postoperative day (p=0.0001). There was no significant difference in pain score or opiate sparing properties between the groups (p=0.92). There was no significant difference in postoperative respiratory tract infection, anastomotic leak or wound complications between the groups (p=0.2, p=1.0 and p=0.5 respectively). The RSC group had a higher incidence of ileus than the EA group (4/24 vs 2/85, p=0.026). However, the numbers were too small to draw a reliable conclusion.

Conclusions

The use of ultrasonography guided RSCs has demonstrated effective postoperative analgesia equivalent to EA with the potential benefits of a reduced incidence of hypotension. A prospective randomised trial is now underway to compare RSC and EA in open abdominal and pelvic surgery.     

TUMOUR PRESENTING AS A RETROSTERNAL ABSCESS FOLLOWING MEDIAN STERNOTOMY

A 73-year-old lady, who underwent coronary artery bypass grafting eight months previously, presented with rigors and chest pain. The upper sternum was tender, swollen and erythematous, suggesting a retrosternal abscess. Radiological investigation supported the clinical diagnosis. Local infections following median sternotomy are uncommon, most being early and superficial. Late infections are very uncommon, and should suggest alternative pathology. Following open surgical drainage, histology showed the mass to be a poorly differentiated adenocarcinoma. The primary tumour was never found.     

Hepatic cavernous hemangioma: magnetic resonance imaging. Work in progress

Using a 0.35-T superconducting magnet and spin echo imaging, we prospectively evaluated 11 patients who had proved hepatic cavernous hemangioma. Magnetic resonance (MR) identified more lesions than either contrast-enhanced CT, or ultrasonography. The MR appearance was consistent; hemangiomas were homogeneous and generally isointense at short TR and TE intervals but were hyperintense at long TR intervals and greatly hyperintense at long TR and long TE intervals. However, the MR appearance of hemangioma was not specific; 2/14 other focal hepatic masses had similar features. The calculated relaxation times (T1, T2) were not useful in lesion characterization, although the intensity ratio of hemangioma to normal liver at the TR = 2.0 sec TE = 56 msec pulse sequence was useful in diagnosis since hemangiomas always had a ratio greater than 1.4.