(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A 33 year-old patient with no relevant clinical history presented in August 2007 with right paravertebral rigidity. Patient had previously undergone kinetic physical therapy and been prescribed anti-inflammatory medication. In December 2007, patient presented to Neurology with right brachial paresis (3/5), positive osteotendinous reflexes, and cervical pain. MRI (Figure 1) showed a hyperintense intraspinal lesion on T2 sequence with contrast enhancement between C2-C7. Diffuse thickening of the spinal cord was also appreciated. January 2008: CSF showed high protein content, but was negative for oligoclonal bands. PCR for HSV and TB were also negative, as was serum NMO-IgG. Evoked potentials showed bilateral increase in latency (117.5 OD-115.5 OI). The condition was interpreted as myelitis. Patient began treatment with methylprednisolone (5 pulses), in spite of which medical condition worsened, developing nystagmus, muscle spasms, and progression of motor deficit with altered osteotendinous reflexes (February-March 2008). In March-April 2008, bilateral hand paresthesias, incontinence, severe right hemiparesis and sensory alterations were observed. In April 2008, patient was brought to our institution presenting bradycardia, hypotension (shock), and respiratory failure. Physical exam revealed flaccid tetraplegia, generalized areflexia, reactive isochoric pupils and horizontal nystagmus. Imaging revealed spinal lesion had increased in size and extended to the medulla (Figure 2). Anoxic-ischemic encephalopathy was diagnosed. Patient died in May 2008.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A 33-year-old male patient reported on head and neck pain radiating into the left maxilla, that had already persisted for 5 years presented in the clinic, as he experienced an acute neuralgic pain provoked by physical activity (VAS 8/10 points) as a new symptom. MRI showed a left-sided hypointense, polyglobulated tumor in the left cerebello-pontine angle, with irregular contrast enhancement and hypointensity on T1 and T2 images (Figs. 1a, 1b, 1c). The tumor exerted pressure on the medulla oblongata, resulting in perifocal edema. By cranial CT (Fig. 1d) the tumor had a strong hyperdense signal. The patient complained of no other neurological deficits. The tumor was extirpated microneurosurgically using electro-physiological monitoring via retromastoidal approach and semisitting position of the patient. Since the lesion was adjacent to the brain stem, a thin layer was left (intraoperative pictures of the tumor: Figs. 1e, 1f). Postoperatively, the patient sustained a new facial and glossopharyngeal palsy, which considerably improved at 3 months' follow-up.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A 33-year-old Chinese woman presented with intermittent slurring of speech, dysphasia together with right upper limb and facial weakness for two months with gradual worsening of the symptoms. Physical examination found decreased pin-prick sensation over right C6 to C8 dermatome and impaired proprioception in right hand. CT scan with contrast showed a well-demarcated contrast-enhancing left frontal tumor measuring 4.5 x 4.2 x 3 cm with perilesional edema and slight mass effect. Cystic changes were observed. The tumor was close to the cortical surface but not connected to the meninges (Figure 1). Surgical exploration found a non-encapsulated, well-circumscribed, vascularized tumor in the left frontal lobe. Tumor debulking under intraoperative cerebral function monitoring was performed. Around 95% of tumor was removed but complete excision could not be achieved due to significant decrease in amplitude of the brain motor evoked potentials. The patient recovered well after the operation with complete restoration of the function in the precentral and postcentral gyri as well as Broca's area.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

33-year-old Thai male patient presented with three weeks history of progressive bilateral lower limb weakness and paresthesia from below the level of the umbilicus. He was admitted at Sakaeo Crown Prince Hospital and first diagnosed with HIV/AIDS. He did not receive antiretroviral drugs before. Neurological examination showed loss of motor power of both lower extremities. Sensory loss was detected in all dermatomes below T10. Areflexia was observed in both legs. The meningeal sign was negative. The other systems revealed no remarkable change. The blood test displayed mild anemia, hyponatremia, and hypokalemia. His CD4 count was 14 cells/?L. Magnetic resonance imaging (MRI) of the lumbar spine showed a 1.4x1.3x1.0 cm round homogenous enhancing, T1/T2 Wi-low-to-iso/mild heterogenous hypersignal intensity, intradural mass lesion at L1 vertebral body level [Figure 1a]. Radiologically, the differential diagnosis included schwannoma, myxopapillary ependymoma, paraganglioma, and tuberculoma. He was treated but his symptoms did not improve. Few weeks later, he was referred to a specialist at our hospital. Surgeon performed lumbar laminectomy with gross total resection of tumor. Postoperatively, he developed progressive dyspnea with clinical suspicion for Pneumocystis jiroveci pneumonia (PJP) infection. He was treated but his clinical symptom got worse. Finally, he developed respiratory failure and expired two weeks after operation.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A 33-year-old male presented with a 2-week old uncomfortable mass within his left testicle. His serum -hCG was elevated (345.2 mIU/mL). Ultrasound examination demonstrated a heterogeneous, hypoechoic mass. The patient subsequently underwent left radical orchiectomy and epididymectomy. Two weeks after the operation -hCG level was less than 2 mIU/ml. Clinical and radiological staging was negative.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

The patient is a 33 year old female who presented for a routine clinical evaluation during a twin pregnancy. The patient was asymptomatic otherwise and appeared to be in good health. The patient's gestational age was 22 weeks at clinical presentation. Routine laboratory investigation of the peripheral blood showed an absolute neutrophilia along with the following clinical laboratory values:

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A 31-year-old, previously healthy woman experienced a new-onset generalized seizure with subsequent right-sided weakness in the 37th week of her pregnancy. History revealed no significant nausea or vomiting (other than that associated with the first trimester of pregnancy) and no prior history of seizures. The patient did, however, report a history of slowly-increasing weakness in her right leg over the past several months. Routine prenatal care had been uneventful and negative for gestational diabetes or hypertension.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A 33 year old female patient presented in June 2009 with progressive loss of vision for the last 12 months plus occasional episodes of headache. In the last 3 months her vision deteriorated even further with progressive temporal amaurosis, and she started having depression with episodes of extreme anxiety. She developed amenorrhea since her last pregnancy 8 years ago with episodes of galactorrhea. CT scan (Figure 1) showed a mass lesion in the sellar region suggestive of meningeoma or pituitary adenoma. She received bromocriptine 2.5mg/day with no reduction of the lesion. She developed panhypopituitarism with normal levels of prolactin. Further MRI showed a large lesion infiltrating cavernous sinuses and compressing the optic nerve. Transsphenoidal surgical treatment was performed. Two months after the first operation she returned to hospital with complete bilateral amaurosis and a new MRI showed residual lesion. A new sub-frontal neurosurgery was performed and most of the lesion was resected. The patient developed diabetes insipidus but remains under control.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A 34 year-old otherwise healthy man presented with new onset headaches, mild confusion, and subtle left-sided weakness. An MRI scan showed a large heterogeneous 8.9cm x 6.0cm right fronto-temporo-parietal mass with nodular enhancement, significant surrounding edema, and 15mm of midline shift. He underwent an urgent right craniotomy, and began appropriate therapy. Unfortunately, within one week of completion of this therapeutic regimen, his symptoms worsened. He was found to have multiple new bilateral dural-based nodular enhancing lesions on repeat brain MRI. No spinal abnormalities were found. He underwent resection of one of the new lesions. The patient was initiated on a new treatment plan, but unfortunately, neuroimaging revealed further progression of disease (Figure 1). He passed away 5 months and 1 day after diagnosis.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

The patient is a 34 year-old morbidly obese man who presented with abdominal pain and dysuria. A CT scan was performed and revealed a small nodule on the dome of his bladder. Cystoscopy was performed and demonstrated a 2-3 cm tumor at the bladder dome with purulent discharge. A partial cystectomy was performed.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

This 34 year-old man presented with a five month complaint of bitemporal hemianopsia. For two years he had decreased visual acuity and increased intraocular pressure treated medically. Magnetic resonance imaging revealed widening of the pituitary fossa and an intrasellar, dumbbell shaped, enhancing mass 3 cm in diameter, extending into the suprasellar region pushing on the optic chiasm (Figure 1). The mass was partially excised, but regrew in three months causing the same symptoms. A second excision was performed. Three months later the tumor again regrew with extension into the sphenoid sinus, and the patient underwent a third excision. Following surgery, the patient was given radiotherapy and one cycle of chemotherapy (adriamycin, dacabarzine, and ifosfamide). Follow-up PET-CT three months after the third surgery showed no evidence of hypermetabolic residual/recurrent tumor.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

The patient was a 35-year-old African American woman with HIV/AIDS (CD4 count 95/ml) and no history of HAART therapy, who was admitted from an outside hospital for further management of altered mental status and hypercarbic respiratory failure. Upon admission, the patient was unresponsive and ventilator dependent. On neurologic exam she had no response to painful stimuli, as well as decreased deep tendon and pupillary reflexes. A chest X-ray failed to demonstrate any pulmonary lesions. A CT of the head without IV contrast revealed an infiltrating hypodense mass within the basal forebrain extending inferiorly to the level of the basilar cisterns, involving the thalami and cerebral peduncles bilaterally (Figure 1). Diffuse brain volume loss was also noted. A lumbar puncture was performed for CSF analysis, which showed lymphocytic pleocytosis (56 nucleated cells/ml with 92% lymphocytes), low glucose (23 mg/dl) and elevated protein (208 mg/dl). An infectious disease was suspected. PCR analysis of the CSF was negative for Mycobacterium tuberculosis, HSV, VZV, CMV and JC virus. There was low positivity for EBV DNA. Serologic studies were consistent with past infections with EBV and CMV and were negative for toxoplasmosis, histoplasmosis, Cryptococcus and West Nile virus. VDRL was non-reactive. CSF and blood cultures for bacteria, fungal organisms and acid fast bacilli were negative. The patient received empiric therapy for bacterial meningitis, including Mycobacterium tuberculosis, HSV/VZV encephalitis and coverage for fungi with amphotericin. Her neurologic status progressively deteriorated. She lost all deep tendon reflexes and her left pupil became fixed and dilated. The presence of corneal reflexes was the only sign of remaining brain stem function. The decision to end life sustaining treatment was made and the patient expired. Consent for limited autopsy of the brain was obtained from the family.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A previously healthy, 35-year-old man presented with a four-week history of painful swelling on his right forehead. CT imaging showed a solitary, 1 cm osteolytic lesion within the diploic space of the right frontal bone, involving the inner and outer tables (Figure 1). On MRI, the lesion was heterogeneously enhancing and extended into subgaleal tissue and epidural space. It was resected and the patient was discharged in good condition.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

The patient is 35-year-old previously healthy native African male, who moved to the United States two years ago. He presented to an outside facility with a chief complaint of anal and rectal bleeding. Laboratory values are unremarkable, and include: hemoglobin 13.1 gm/dL, hematocrit 39%, white blood cell count 6,000 cell/cc, eosinophils 2.9% (normal 0.2-6.0%), platelets 224, calcium 9.2 mg/dL, albumin 3.7 g/dL, glucose 94 mg/dL, AST 51 IU/L, ALT 45 IU/L, alkaline phosphatase 47 IU/L, total bilirubin 0.5 mg/dL, sodium 135 mmol/L, potassium 4 mmol/L, chloride 110 mmol/L, blood urea nitrogen 9 mg/dL, and creatinine 1.1 mg/dL. Colonoscopy revealed thrombosed external hemorrhoids and mild erythema in the rectal area. There were also small, non-bleeding internal hemorrhoids. The terminal ileum appeared normal. Clinically, the differential diagnosis included colonoscopy preparation-related changes and a mild colitis. The colonoscopy findings were sufficient to explain mild hematochezia, and fiber supplementation with repeat screening colonoscopy in ten years was recommended.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

The patient is a previously healthy 35-year-old man who was admitted to our hospital for evaluation after experiencing vomitus, dizziness and headache for one month. A neurological examination elicited no abnormalities. CT and MR imaging were performed and revealed a 3.5 x 3.2 cm solitary, well-delineated, extra-axial midline mass arising from the frontal falx cerebri. The lesion was isointense to the cortex on T2 (Figure 1) and hypointense on T1, with a marked homogenous enhancement after intravenous contrast administration (Figures 2 and 3). Based on these findings, the radiological diagnosis was meningioma of the falx. At surgery, the tumour appeared as an extra-axial lesion and was removed via a left midline frontal craniotomy. The excision was macroscopically complete.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A 35-year-old woman presented for neurological evaluation after a single episode of speech disruption consisting of word finding difficulty and a partial motor seizure followed by one hour of confusion. A head MRI scan was performed, which showed a 2.7 by 2.0 by 2.5 cm dural-based contrast enhancing lesion along the left posterior temporal lobe (Figure 1). An EEG at the time of presentation was negative, but the patient was placed on prophylactic Dilantin therapy. She was referred for neurosurgical evaluation, and a recommendation was made for surgical resection. A left parietal-temporal craniotomy was performed to resect the tumor. At surgery, a firm dural-based lesion was encountered with no evidence of brain invasion or involvement, and a gross total resection was performed. The patient tolerated the procedure well, and was discharged home on postoperative day three. The patient had no further seizures or episodes of speech difficulty, and was tapered off of her anticonvulsants six months following surgery, with a second EEG negative at that time. Follow-up MRI scans at 6 and 12 months showed no evidence of tumor recurrence, and she continues to have a normal neurological exam.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A 35 year old woman was admitted to our hospital with symptoms and signs of acromegaly that started one year earlier. Physical examination detected clubbing of her fingers, enlargement of her jaws, a carpal tunnel syndrome along with joint and neck pain. Laboratory findings showed hypothyroidism, secondary hypogonadism, diabetes mellitus and anemia. Cranial MRI revealed an intra- and suprasellar mass lesion with radiological signs of a chiasma syndrome. She was treated with a somatostatin therapy. Although the clinical symptoms improved over the next three months, Insulin like Growth Factor-1 levels ( a marker for acromegaly) continued to be at pathological levels. The patient therefore underwent a transphenoidal resection of the intrasellar mass.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A 35-year-old G2P2, presented at nine-months post-partum to her gynecologist for increased left labial swelling over a 2-month period. Pertinent medical history included two spontaneous vaginal deliveries, menorrhagia with known uterine fibroids, and no abnormal Pap smears. Physical examination at that time demonstrated a painless 7 cm mass in the area of the left Bartholin gland. An incision and drainage performed by the primary gynecologist revealed expression of gelatinous material. The mass recurred over the next two months, and the patient transferred her care to our institution. A radical vulvectomy with additional deep margins was performed at our institution.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A 35-year-old woman presented with one month's history of progressive bilateral leg weakness and altered sensation. There had been no pain. She had noted urinary frequency and constipation in the previous two weeks. On examination, the patient had diffuse lower extremity weakness (2-3/5), with a T6 sensory level to pain and temperature sensation. Proprioception was preserved. Post-void residuals exhibited urinary retention. There was sacral hypesthesia and decreased rectal tone. She was mildly hyperreflexic (3/4) at the knees and ankles without clonus; both great toes were upgoing. A T1-weighted MRI demonstrated a T4-5 intradural mass ventral to the spinal cord (Fig. 1A), with an enhancing dural tail (Fig. 1B), consistent with meningioma. The lesion was dark on T2-weighted images (Fig. 1C).

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

We present a 36-year-old cognitively intact male, with history of work-related solvent exposure who consulted for headache, vomiting and fever in September 2009. Symptoms persisted in spite of antibiotic therapy. CT scan showed a hypodense image in the left parietal lobe. MRI revealed a parietal lesion hypointense on T1, hyperintense on T2, and FLAIR, without mass effect (Fig. 1a). Thoracic CT scan showed bi-apical interstitial infiltrates. Standard TB treatment was indicated along with steroids, obtaining a partial clinical response. Two months later, following steroid tapering, significant clinical deterioration was observed with fever, headaches and nausea. Patient was re-evaluated showing no changes on MRI. PCR testing for several microorganisms was negative. Differential diagnoses considered were: recurrent Meningitis NOS vs. vasculitis vs. ADEM (Acute Disseminated Encephalomyelitis). A new course of methylprednisolone was administered; after which patient requested voluntary discharge. In December 2009, patient returned with persistent fever and headache. A methylprednisolone bolus was administered and partial, transient response observed. At this time, the diagnosis considered was ADEM refractory to steroids, and treatment was switched to immunoglobulin therapy, which led to a complete clinical response. Once again, patient requested voluntary discharge, but had to be re-admitted later, due to headache, fever, mental confusion and aphasia in January 2010. New CSF PCRs ruled out viral diseases and TB. Other differential diagnoses considered included: Marburg's disease, CNS lymphoma and Neuro-Behçet's disease. The patient then suffered rapid clinical decline, developing limb weakness, somnolence and hyponatremia and died in January 2010.